GENETIC ANALYSIS OF QUANTITATIVE TRAITS IN AROMATIC RICE (Oryza sativa L.) LAVURI KRISHNA M.Sc. (Ag.)

Transcription

1 GENETIC ANALYSIS OF QUANTITATIVE TRAITS IN AROMATIC RICE (Oryza sativa L.) LAVURI KRISHNA M.Sc. (Ag.) DOCTOR OF PHILOSOPHY IN AGRICULTURE (GENETICS AND PLANT BREEDING) 2014

2 GENETIC ANALYSIS OF QUANTITATIVE TRAITS IN AROMATIC RICE (Oryza sativa L.) BY LAVURI KRISHNA M.Sc. (Ag.) THESIS SUBMITTED TO THE PROFESSOR JAYASHANKAR TELANGANA STATE AGRICULTURAL UNIVERSITY IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE AWARD OF THE DEGREE OF DOCTOR OF PHILOSOPHY IN AGRICULTURE (GENETICS AND PLANT BREEDING) CHAIRMAN: Dr CH. SURENDER RAJU DEPARTMENT OF GENETICS AND PLANT BREEDING COLLEGE OF AGRICULTURE PROFESSOR JAYASHANKAR TELANGANA STATE AGRICULTURAL UNIVERSITY RAJENDRANAGAR, HYDERABAD

3 DECLARATION I, LAVURI KRISHNA, hereby declare that the thesis entitled GENETIC ANALYSIS OF QUANTITATIVE TRAITS IN AROMATIC RICE (Oryza sativa L.) submitted to the Professor Jayashankar Telangana State Agricultural University for the degree of DOCTOR OF PHILOSOPHY IN AGRICULTURE in the major field of GENETICS AND PLANT BREEDING is the result of original research work done by me. I further declare that the thesis or any part thereof has not been published earlier elsewhere in any manner. Date: Place: Hyderabad (LAVURI KRISHNA) I.D.No. RAD/

4 CERTIFICATE Mr. LAVURI KRISHNA has satisfactorily prosecuted the course of research and that the thesis entitled GENETIC ANALYSIS OF QUANTITATIVE TRAITS IN AROMATIC RICE (Oryza sativa L.) submitted is the result of original research work and is of sufficiently high standard to warrant its presentation to the examination. I also certify that neither the thesis nor its part thereof has been previously submitted by him for a degree of any University. Date : Place: Hyderabad (Dr. CH. SURENDER RAJU) Chairperson of the Advisory Committee

5 CERTIFICATE This is to certify that the thesis entitled GENETIC ANALYSIS OF QUANTITATIVE TRAITS IN AROMATIC RICE (Oryza sativa L.) submitted in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY IN AGRICULTURE (GENETICS AND PLANT BREEDING) of the Professor Jayashankar Telangana State Agricultural University, Hyderabad is a record of the bonafide research work carried out by Mr. LAVURI KRISHNA under our guidance and supervision. The subject of the thesis has been approved by the Student s Advisory Committee. No part of the thesis has been submitted by the student for any other degree or diploma. The published part and all assistance and help received during the course of investigations have been duly acknowledged by the author of the thesis. (Dr. CH. SURENDER RAJU) Chairperson of the Advisory Committee Thesis approved by the student s advisory committee Chairperson Member Member Member Dr. Ch. Surender Raju Principal Scientist (Br.) & Head Rice Research Center (ACRIP) Rajendranagar, Hyderabad-30 Dr. S. Sudheer Kumar Professor (Academic) Administrative Office Prof. Jayashankar Telangana State Agricultural University Rajendranagar, Hyderabad-30 Dr. S. Narender Reddy Professor Department of Crop Physiology College of Agriculture, Rajendranagar Hyderabad-30 Mr. M.H.V Bhave Associate Professor Statistics and Applied Mathematics College of Agriculture, Rajendranagar Hyderabad-30 External- Examiner of Final Viva-Voce Dr. V. Ravindra Babu Project Director Directorate of Rice Research Rajendranagar, Hyderabad-30 Date of Final Viva-Voce :

6

7 ACKNOWLEDGEMENTS First and foremost, I offer my obeisance to the Almighty for his boundless blessing, which accompanied me in all the endeavors. I am pleased to place my profound etiquette to Dr. Ch. Surender Raju, Principal Scientist (Plant Breeding), Rice Section, Agricultural Research Institute, Rajendranagar, Hyderabad and esteemed Chairperson of my Advisory Committee for his learned counsel, unstinted attention, arduous and meticulous guidance on the work in all stages. His keen interest, patient hearing and constructive criticism have installed in me the spirit of confidence to successfully complete the task. I deem it my privilege in expressing my fidelity to Dr. S. Sudheer Kumar, Professor, Department of Genetics and Plant Breeding, College of Agriculture, Rajendranagar, Hyderabad and member of my Advisory Committee for his munificent acquiescence and meticulous reasoning to refine this thesis and most explicitly to reckon with set standards. I am grateful to Dr. S. Narender Reddy, Professor, Dept. of Crop Physiology and Mr. M.H.V Bhave, Associate Professor, Statistics and Applied Mathematics, College of Agriculture, Rajendranagar, Hyderabad and members of my advisory committee for their pragmatic suggestions throughout the period of study. I am extremely thankful to Dr. T. Dayakar Reddy, Professor and Head of the Department of Genetics and Plant Breeding for his sustained encouragement, constant support and valuable suggestions offered during my research and cooperation during submission of thesis. I owe respectable regards and heartfelt thanks to the staff members of Genetics and Plant Breeding Professors Dr.N.A. Ansari, Dr.K.V. Radhakrishna, Dr. Kuldeep Singh Dangi, Dr. Bharathi, Dr. M. Sujatha, Associate Professors Dr. K.Radhika, Dr.V.Anuradha Dr. Hemalatha, Dr. Eswari, and Dr. Murali Krishna and Assistant Professor Dr.J. Suresh, Department of Genetics and Plant Breeding, College of Agriculture, Rajendranagar, Hyderabad for their kind cooperation, whole hearted help and valuable suggestions during my course and research work. I owe my special debt of sincere gratitude to Dr. R. Jagadeeshwar, Principal Scientist (Pathology), Dr. P. Raghurami Reddy, Principal Scientist (Agronomy), Dr. Ch. Damodar Raju, Senior Scientist (Plant Breeding), Dr. N. Rama Gopala Varma, Senior Scientist (Entomology), Dr.S. Vanisree, Senior Scientist (Plant

8 Breeding) and other staff members and workers of Rice Section, A.R.I, Rajendranagar, Hyderabad. I express my heartfelt gratitude and thanks to Dr. V. Ravindra babu, Principal Scientist and Head, Crop Improvement Division, Dr. L.V. Subba Rao, Principal Scientist (Plant Breeding), Directorate of Rice Research, Rajendranagar, Hyderabad and Dr.Y. Suryanarayana, Principal Scientist (Rice), ARS, Nellore for providing the part of the material in the present study. I express my heartfelt gratitude and thanks to my class mates, colleagues, and friends Dileep, Satyanarayana, Bhadru, Saida, Rajani, Venkanna, Latheef, Murali, Nagesh, Madhu, Shialesh, Yadav, Vijay, Anand, Patne, Usha and Santu for their love, affection, co-operation which helped for my goal setting during my studies. I express my sincere thanks to 2010, 2011 and 2012 batch polytechnic students of Agricultural Polytechnic, Kampasagar for helping in data work and Suresh Reddy, Anji, Padma, Prameela of A, R, S, Kampasagar for helping in crossing work and also Scientists, Staff and workers of A, R, S, Kampasagar and Rice Section, ARI, Hyderabad for their invaluable co-operation and assistance during this work. I am grateful to the authorities of Acharya N.G. Ranga Agricultural University for granting me deputation for prosecuting higher studies. My deep sense of love and gratitude towards my dear wife Vanitha Priyadarshini, for her moral support, sacrifices, co-operation and constant encouragement and my lovely daughter Ritkriti Krishna and my son Ashwath for their help in petty works which enabled me for timely completion. With boundless affection, I would hearty acknowledge the constant encouragement and inspiration given to me by beloved sister Krishna Veni, brother-inlaw Laxman and their children s Lohit and Sonu and my brother Gopi.. Finally I am in dearth of words to express my unboundful gratitude and genuflect love to my beloved parents Sri. L. John (Late) and Smt. Aurna for their dedicated efforts to educate me to this level. (KRISHNA. L)

9 LIST OF C O N T E N T S Chapter No. Title Page No. I II III IV V INTRODUCTION REVIEW OF LITERATURE MATERIAL AND METHODS RESULTS AND DISCUSSION SUMMARY AND CONCLUSIONS LITERATURE CITED APPENDICES

10 LIST OF SYMBOLS AND ABBREVIATIONS % : Per cent σ 2 e : Environnemental variance σ 2 g : Genotypic variance σ 2 p : Phenotypic variance σ p : Phenotypic standard deviation ANOVA : Analysis of Variance cm : Centimeter CMS : Cytoplasmic Male Sterile d.f. : Degrees of freedom et al. : and others people etc. : and so on F 1 : First filial generation F 2 : Second filial generation F 3 : Third filial generation Fig. : Figure G x E : Genotype x Environment gca : General combining ability gm : Gram Kg : Kilogram MS : Mean Sum of Squares P 1 : Parent 1 P 2 : Parent 2 per se : As such with mean RBD : Randomized Block Design S.E : Standard Error sca : Specific combining ability viz., : Namely vs. : Against χ 2 : Chi-square

11 LIST OF TABLES Table No. Title 2.1 Review of literature on gene action governing different traits in rice Review of literature on heterosis and inbreeding depression for various traits in rice Review of literature on variability, heritability and genetic advance for various traits in rice Review of literature on association of yield component characters with grain yield per plant in rice Review of literature on direct and indirect effects of yield contributing traits on grain yield in rice 3.1 Salient features of selected parents for crossing 4.1 Analysis of variance for grain yield, yield contributing characters and grain quality characteristics in aromatic rice 4.2 Mean performance of parents and crosses for fourteen characters Estimation of heterosis over mid parent, better parent, standard heterosis and inbreeding depression for days to 50 per cent flowering, plant height and number of productive tillers per plant. Estimation of heterosis over mid parent, better parent, standard heterosis and inbreeding depression for days to panicle length, panicle weight and number of filled grains/panicle. Estimation of heterosis over mid parent, better parent, standard heterosis and inbreeding depression for 1000 grain weight, grain yield per plant and kernel length. Estimation of heterosis over mid parent, better parent, standard heterosis and inbreeding depression for kernel breadth, kernel L/B ratio and kernel length after cooking. Estimation of heterosis over mid parent, better parent, standard heterosis and inbreeding depression for kernel elongation ratio and head rice recovery. Analysis of variance (mean squares) for grain yield and grain characteristics Analysis of variance for combining ability for grain yield, yield contributing characters and grain characteristics General combining ability (gca) effects of parents for yield and grain characteristics. Specific combining ability (sca) effects of crosses for yield and grain characteristics. Top ranking desirable parents for gca with their per se performance for each of fourteen characters Promising general combiners for yield and quality characters 4.14 Top ranking desirable crosses for sca with their per se performance, heterobeltiosis and inbreeding depression for each of fourteen characters Page No.

12 Table No Title Promising crosses based on sca effects, per se performance and heterosis for yield and yield contributing characters in rice 4.16 Generation means for days to 50% flowering Page No Scaling test values for days to 50% flowering 4.18 Gene effects for days to 50% flowering 4.19 Generation means for plant height 4.20 Scaling test values for plant height 4.21 Gene effects for plant height 4.22 Generation means for number of productive tillers/plant 4.23 Scaling test values for number of productive tillers/plant 4.24 Gene effects for number of productive tillers/plant 4.25 Generation means for panicle length 4.26 Scaling test values for panicle length 4.27 Gene effects for panicle length 4.28 Generation means for panicle weight 4.29 Scaling test values for panicle weight 4.30 Gene effects for panicle weight 4.31 Generation means for number of filled grains/panicle 4.32 Scaling test values for number of filled grains/panicle 4.33 Gene effects for number of filled grains/panicle 4.34 Generation means for 1000 grain weight 4.35 Scaling test values for 1000 grain weight 4.36 Gene effects for 1000 grain weight 4.37 Generation means for grain yield per plant 4.38 Scaling test values for grain yield per plant 4.39 Gene effects for grain yield per plant 4.40 Generation means for kernel length 4.41 Scaling test values for kernel length 4.42 Gene effects for kernel length

13 Table No. Title 4.43 Generation means for kernel breadth 4.44 Scaling test values for kernel breadth 4.45 Gene effects for kernel breadth 4.46 Generation means for kernel L/B ratio 4.47 Scaling test values for kernel L/B ratio 4.48 Gene effects for kernel L/B ratio 4.49 Generation means for kernel length after cooking 4.50 Scaling test values for kernel length after cooking 4.51 Gene effects for kernel length after cooking 4.52 Generation means for kernel elongation ratio 4.53 Scaling test values for kernel elongation ratio 4.54 Gene effects for kernel elongation ratio 4.55 Generation means for head rice recovery 4.56 Scaling test values for head rice recovery 4.57 Gene effects for head rice recovery 4.58 Direction of dominance [h] and dominance x dominance [l] gene effects for various characters in ten crosses 4.59 Genetic parameters for yield and of quality characters in F 2 progenies 4.60 Mean performance of F 3 progenies for yield and grain quality characteristics 4.61 Genetic parameters for yield and quality characters in F 3 progenies Simple correlations coefficients among grain yield per plant and its component characters in F 1, F 2 and F 3 generations Path coefficients for yield and yield components in F 1, F 2 and F 3 generations Genetic parameters (cross wise) in 11 promising crosses with low inbreeding depression. Page No.

14 LIST OF ILLUSTRATIONS Figure Title No. 4.1 Mean values of parents and crosses for days to 50% flowering 4.2 Mean values of parents and crosses for plant height Page No. 4.3 Mean values of parents and crosses for number of productive tillers/plant 4.4 Mean values of parents and crosses for grain yield per plant 4.5 Standard heterosis exhibited by promising hybrids for gays to 50 per cent flowering 4.6 Heterobeltiosis exhibited by promising hybrids for plant height 4.7 Standard heterosis exhibited by promising hybrids for productive tillers/plant 4.8 Standard heterosis exhibited by promising hybrids for panicle length Heterosis, heterobeltiosis and standard heterosis exhibited by promising hybrids for panicle weight Heterosis, heterobeltiosis and standard heterosis exhibited by promising hybrids for filled grains/panicle 4.11 Standard heterosis exhibited by promising hybrids for 1000 grain weight 4.12 Heterobeltiosis and standard heterosis exhibited by promising hybrids for grain yield per plant 4.13 Standard heterosis exhibited by promising hybrids for kernel breadth Standard heterosis exhibited by promising hybrids for kernel length after cooking Heterosis, heterobeltiosis and standard heterosis exhibited by promising hybrids for kernel elongation ratio 4.16 Standard heterosis exhibited by promising hybrids for head rice recovery Heterosis and inbreeding depression exhibited by promising hybrids for number of productive tillers/plant Heterosis and inbreeding depression exhibited by promising hybrids for panicle length Heterosis and inbreeding depression exhibited by promising hybrids for panicle weight Heterosis, Heterobeltiosis and inbreeding depression exhibited by promising hybrids for number of filled grains/panicle

15 Figure No Title Heterosis, Heterobeltiosis and inbreeding depression exhibited by promising hybrids for 1000 grain weight Heterosis, Heterobeltiosis and inbreeding depression exhibited by promising hybrids for grain yield per plant Heterosis, Heterobeltiosis and inbreeding depression exhibited by promising hybrids for kernel length Heterobeltiosis and inbreeding depression exhibited by promising hybrids for kernel L/B ratio Mean performance, sca effects, Heterobeltiosis and inbreeding depression exhibited by promising hybrids for days to 50% flowering Mean performance, sca effects, Heterobeltiosis and inbreeding depression exhibited by promising hybrids for plant height Mean performance, sca effects, standard heterosis and inbreeding depression exhibited by promising hybrids for number of productive tillers/plant Mean performance, sca effects, standard heterosis and inbreeding depression exhibited by promising hybrids for panicle length Mean performance, sca effects, standard heterosis and inbreeding depression exhibited by promising hybrids for number of filled grains/panicle Mean performance, sca effects, heterobeltiosis, standard heterosis and inbreeding depression exhibited by promising hybrids for grain yield per plant Mean performance and sca effects exhibited by promising hybrids for kernel length Mean performance and sca effects exhibited by promising hybrids for kernel breadth Mean performance, sca effects, heterobeltiosis and inbreeding depression exhibited by promising hybrids for kernel elongation ratio Mean performance, sca effects, heterobeltiosis, standard heterosis and 4.34 inbreeding depression exhibited by promising hybrids for head rice recovery 4.35 Significant correlations between characters in F 1 generation 4.36 Significant correlations between characters in F 2 generation 4.37 Significant correlations between characters in F 3 generation 4.38 Path diagram showing direct and indirect effects on yield in F 1 generation Page No Path diagram showing direct and indirect effects on yield in F 2 generation 4.40 Path diagram showing direct and indirect effects on yield in F 3 generation

16 LIST OF PLATES Plate No. Title 3.1 Evaluation of parents, F 1 s and F 2 s at Agriculture Research Station, Kampasagar, Nalgonda district (Telangana) Best specific and heterotic cross for yield characters (panicle length, 4.1 panicle weight, number of filled grains/panicle and 1000 grain weight and grain yield) Best specific and heterotic cross for yield characters (number of 4.2 productive tillers/plant, panicle weight, number of filled grains/panicle and grain yield) Best specific and heterotic cross for yield and quality characters (panicle 4.3 length, number of filled grains/panicle, 1000 grain weight, kernel length, kernel breadth, kernel L/B ratio and grain yield) 4.4 Top ranking crosses with heterosis and specific combining ability for kernel length 4.5 Top ranking crosses with heterosis and specific combining ability for kernel breadth 4.6 Top ranking crosses with heterosis and specific combining ability for kernel L/B ratio 4.7 Top ranking crosses with heterosis and specific combining ability for kernel length after cooking 4.8 Top ranking crosses with heterosis and specific combining ability for kernel elongation ratio 4.9 Top ranking crosses with heterosis and specific combining ability for head rice recovery Page No.

17 Name of the Author : L. KRISHNA Title of the thesis : GENETIC ANALYSIS OF QUANTITATIVE TRAITS IN AROMATIC RICE (Oryza sativa L.) Degree : DOCTOR OF PHILOSOPHY Faculty : AGRICULTURE Discipline : GENETICS AND PLANT BREEDING Major Advisor : Dr. CH. SURENDER RAJU University : PROFESSOR JAYASHANKAR TELANGANA STATE AGRICULTURAL UNIVERSITY Year of submission : 2014 ABSTRACT The present investigation was conducted to estimate the combining ability, heterosis, inbreeding depression, heritability, variability, genetic advance, correlations and path coefficients for yield components and grain quality characters crossing 8 parents in diallel design (without reciprocals) at Agricultural Research Station, Kampasagar. Further, through generation mean analysis, the nature and magnitude of non allelic interactions were investigated. Analysis of variance revealed the presence of sufficient variation in the experimental material. Through combining ability analysis, the parents, Akshyadhan, Basmati 370 and Sumathi were identified as the potential combiners for grain yield and prime component traits, panicle length, panicle weight, filled grains per panicle and 1000 grain weight. Whereas, Improved Pusa Basmati and Basmati 370 combined well for kernel characters including cooking quality traits. As such, these parents could be better utilized for breeding material generation. Among the crosses, Pusa 1121 x Sumathi, BPT 5204 x Basmati 370, Pusa 1121 x Basmati 370, BPT 5204 x NLR 145, Sumathi x Improved Pusa Basmati, RNR 2354 x Sumathi, BPT 5204 x Akshyadhan, RNR 2354 x Basmati 370, NLR 145 x Pusa 1121 and Akshyadhan x Pusa 1121 for different yield components; Pusa 1121 x Sumathi, BPT 5204 x RNR 2354 and BPT 5204 x Basmati 370, Pusa 1121 x Sumathi and Akshyadhan x Improved Pusa Basmati for kernel quality characters were identified as the best specific crosses in view of their high per se performance, sca effects and gca of their respective parents. Significant heterosis over mid and better parents was observed in many cross combinations. The crosses, Akshyadhan x Pusa 1121, Akshyadhan x Sumathi, NLR 145 x Pusa 1121 and RNR 2354 x Improved Pusa Basmati exhibited highly significant heterosis and heterobeltiosis for yield and component characters besides earliness. The other promising crosses for both yield components and quality traits were NLR 145 x Basmati 370, Sumathi x Improved Pusa Basmati, Pusa 1121 x Sumathi and Akshyadhan x Improved Pusa Basmati. High heterosis in F 1 generation was accompanied by high inbreeding depression in F 2 generation for the prime yield

18 component, grains per panicle, whereas, the inbreeding depression was very low for panicle weight and 1000 grain weight. Hence, direct selection for yield improvement through these two characters would be highly beneficial. Considering this point, Akshyadhan x Pusa 1121 for yield potential and BPT 5204 x RNR 2354 and Akshyadhan x Basmati 370 for good cooking qualities with aroma were recommended for straight selection. Generation mean analysis was performed to detect the epistasis and estimate 5 components (m, d, h, i and l) as per 5 parameter model. The C and D scaling tests and the joint scaling test (3 parameter model) confirmed that the additive dominance model was inadequate to explain the inheritance of these characters. Based on the magnitudes of fixable genetic variation ( d & i types) and per se, pedigree selection in segregating generations with respect to crosses, BPT 5204 x Sumathi, RNR 2354 x Basmati 370 and Sumathi x Improved Pusa Basmati (for yield and quality) and BPT 5204 x Akshyadhan, Akshyadhan x NLR 145, Akshyadhan x Pusa 1121 (for grain yield) and BPT 5204 x Pusa 1121, Improved Pusa Basmati x Basmati 370 (for quality alone) was recommended. In F 2 and F 3 generations, among the yield characters, highest PCV and GCV values were recorded for no. of filled grains/panicle followed by grain yield and panicle weight indicating greater scope of obtaining high selection response for these traits. High heritability (F 2 and F 3 ) along with medium to high genetic advance was noticed for the trait, 1000 grain weight and most of the kernel traits, which facilitates direct selection in segregating populations for development of pure lines with good yield potential and quality. Eleven crosses with high per se performance, heterosis coupled with less inbreeding depression were carefully choosen and genetic parameters viz., GCV, PCV, h 2 (b s ) and GA) were estimated to suggest suitable breeding techniques on cross wise basis. Based on these results, direct selection for yield improvement in two crosses viz., Sumathi x Basmati 370 and Akshyadhan x NLR 145 and for quality improvement in five crosses viz., NLR 145 x Pusa 1121, Pusa 1121x Sumathi, Pusa 1121x Improved Pusa Basmati, Sumathi x Improved Pusa Basmati and Improved Pusa Basmati x Basmati 370 was considered as highly feasible and recommended. A critical analysis of both character association and path analysis in F 1, F 2 and F 3 indicated that, among the yield components investigated, panicle weight and no. of filled grains/panicle are very important, as the correlation coefficients as well as the direct effects were high irrespective of the generation. The results of the present study revealed that the nature and magnitude of gene effects differ depending on the cross and character under consideration. Hence, apart from direct selection, the other procedures like recurrent selection or biparental mating in early segregating generations to poolup desired genes is also recommended depending on the cross combination. Taking into consideration the whole genetic analysis through the present investigation, pedigree selection in the cross combinations, Akshyadhan x Pusa 1121, NLR 145 x Pusa 1121 and BPT 5204 x NLR 145 for grain yield and Akshyadhan x Improved Pusa Basmati and Pusa 1121 x Sumathi for kernel dimensions (length, L/B ratio) and BPT 5204 x RNR 2354 and Akshyadhan x Basmati 370 for cooking quality characters was considered as most feasible and rewarding. In respect of other superior crosses, instead of direct selection biparental mating in F 2 generation followed by selection was recommended alternatively.

19 CHAPTER-I INTRODUCTION Rice (Oryza sativa L.) is the unique grain that is almost entirely used as human food, unlike other cereals which are also used extensively as feed. Rice is the world s second most important cereal crop and staple food for more than 60 per cent of the global population providing about 75 per cent of the calorie and 55 per cent of the protein intake in their average daily diet. In India, rice occupies 44.0 M ha with a production of M t and productivity of 2390 kg ha -1. In Andhra Pradesh, it is grown in an area of 4.1 M ha with a production of M t and productivity of 3150 kg ha -1 (CMIE Report, 2012). In rice research, grain quality was initially overshadowed by the need for higher yields and greater pest resistance for attaining self-sufficiency for an expanding population. The price decline in many Asian countries and in the world market over the last two decades renewed interest in grain quality in international and national research programs. Although, secondary to the goal of increasing and sustaining yield, grain quality improvement is important because it enhances consumer's welfare and expands market potential. Aromatic rice with an aroma and flavour constitute a small group of rice in the consideration of consumption, is a special group of rice that is regarded as best in quality (Singh et al., 2000). Although, aromatic rices popular in world market are longgrain types forming the bulk of export, majority of the Indian indigenous aromatic rices are small and medium-grain types, mostly cultivated for home consumption. Some of the small and medium-grained aromatic rices possess excellent aroma and other quality traits like kernel elongation after cooking, taste etc. which could be excellent sources for improving quality in high yielding varieties. With the growing demand for aromatic rices in international market, high emphasis was placed till now on the improvement of basmati types. The improvement of indigenous small and medium-grained aromatic rices was slightly neglected, as they lacked export value. Among these traditional rice varieties, land races of aromatic rice bear special significance because of their special flavour and economic value in the present globalized era (Chaudhury, 2003). Domestic market exists for the indigenous aromatic rice which is popular in their native areas of cultivation. In Andhra Pradesh,

20 aromatic short grain varieties like Godavari Isukalu and Chittimutyalu are commonly grown in the districts like Nizamabad, Karimnagar and Warangal which could be excellent sources for improving quality in high yielding superfine rice varieties of Andhra Pradesh. Research in this direction has been initiated in the state of Andhra Pradesh and has resulted in the release of high yielding basmati variety in 2002 by name Sumati for commercial cultivation. Similarly, short grain aromatic rice varieties like Sugandha Samba facilitated availability of scented rice at affordable price for an average consumer. The fine-grain aromatic varieties promise t ha -1 of yield along with strong aroma. Presently, the yield potential of aromatic long and short-grain varieties is only t ha -1 which is very low as compared to non-basmati high yielding varieties. Hence, there is a need to raise the present productivity levels to t ha -1 which is possible through development of high yielding semi-dwarf aromatic varieties with resistance to biotic and abiotic stresses and improved productivity levels of aromatic short-grain types to replace the locally tall varieties which have got export potential. A perusal of literature indicates scanty information on the genetics of grain quality and yield components of fine grain aromatic rices particularly with respect to short grained ones. This background clearly necessitates studies in this direction towards genetic variability of yield and its components of aromatic rice, which comprises of mainly short and long grained types. Aromatic rice has got paramount importance in breeding programmes in the countries which are self sufficient in their production. Preference is given for kernel length, size, shape, appearance and cooking quality characters especially kernelelongation ratio. As such, the plant breeders should focus their attention towards the improvement of both basmati types and aromatic short-grain rice for quality and high yield potential. Studies on inheritance of aroma confirmed that, mostly it is due to single recessive gene in homozygous condition or 2 genes with complementary gene action. Yield is a complex character determined by a large number of component characters which are considered important in plant breeding. The present rice scientists are intensifying rice breeding efforts for attaining a quantum jump in productivity, qualitatively and quantitatively. The development of high yielding cultivars of rice has been basically directed towards pure line selections based on per se performances because of its self-fertilizing nature. The application of the genetic information to a breeding programme, derived from a suitable mating design, regarding the inheritance of a character would certainly be a great value to a

21 plant breeder in achieving his goal. Among the various available mating designs, diallel mating is oftenly employed to characterize the nature and magnitude of genetic variances and combining ability effects of the parents and crosses for grain yield and yield contributing quantitative characters. Also, a detailed analysis of generation means and genetic parameters in segregating generations is necessary to decide correct breeding method for achieving targets. Keeping in view the above aspects, the present investigation was undertaken with the following objectives involving aromatic grained parents. 1. To determine the nature of gene action controlling quantitative traits and components of genetic variance through diallel analysis involving aromatic parents. 2. To study the inheritance pattern and to find out the magnitude of inter-allelic interaction for quantitative traits by generation mean analysis. 3. To estimate the extent of heterosis for yield and yield components. 4. To quantify the genetic variation, genetic advance and heritability for grain yield and its components in F 2 and F 3 generations. 5. To estimate heritability and genetic advance in promising crosses. 6. To study the character association and direct and indirect effects between yield and yield attributing traits through correlation and path analysis.

22 Chapter II REVIEW OF LITERATURE The present investigation was undertaken to study the heterosis, combining ability and nature of gene action controlling the prime yield and quality traits. The literature available on these aspects is reviewed briefly section wise as under. 2.1 Combining ability 2.2 Heterosis and inbreeding depression 2.3 Generation mean analysis 2.4 Variability, heritability and genetic advance 2.5 Correlations 2.6 Path analysis 2.1 COMBINING ABILITY AND GENE ACTION The ability of parents to transmit their characters to offspring is an important feature in crop breeding. The concept of combining ability was elaborated by Sprague and Tatum (1942) through preliminary studies with corn. The average performance of a line in a cross combination is referred to as general combining ability and is mainly due to additivity of genes, while dominant and epistatic gene actions results in specific combining ability of a cross which is the deviation of crosses from expected values based on average performance of parental lines. Combining ability analysis provides information on nature and magnitude of gene action for the traits of economic importance and also helps in the identification of potential parents and cross combinations. Diallel cross analysis is the one which is commonly used and it also enables to understand the nature of gene action involved in the expression of various characters. Hence, the present study was undertaken to assess the combining ability of promising rice genotypes using half diallel analysis and the literature pertaining to combining ability through different biometrical methods is presented in tabular form in Table 2.1.

23 Table 2.1. Review of literature on gene action governing different traits in rice Gene action Additive Non additive Additive and non additive 1. Days to 50% flowering Chakraborthy et al. (1994) Satyanarayana et al. (2000) Vijaya lakshmi et al. (2008) Ganesan and Rangaswamy (1998) Swain et al. (2003) Pradhan and Singh (2008) Ram et al. (1998) Banumathy et al. (2003) Meenakshi and Devarathinam (1999) Bisne and Motiramani (2005) Roy and Mandal (2001) Panwar (2005) Patil et al. (2003) Raju et al. (2006) Shanthi et al. (2003) Venkatesan et al. (2007) Shanthi et al. (2004) Sharma and Mani (2008) Anand Kumar et al. (2006) Shukla and Pandey (2008) Dhakar and Vinit Vyas (2006) Kumar Babu et al. (2010) Gnana Sekaran et al. (2006) Jayasudha and Sharma (2010) Sharma et al. (2007) Saidaiah et al. (2010) Sanjeev Kumar et al. (2007a) Padmavathi et al. (2012) Dalvi and Patel (2009) Satheesh kumar et al. (2010) 2. Plant height Lokaprakash et al. (1991) Banumathy and Prasad (1991) Reddy (2002) Vijayakumar et al. (1994) Ramalingam et al. (1993) Vijaya lakshmi et al. (2008) Ganesan et al. (1997) Chakraborthy et al. (1994) Ramalingam et al. (1997) Dhanakodi and Subramanian (1994) Ganesan and Rangaswamy (1998) Rogbell and Subbaraman (1997) Ram et al. (1998) Manonmani and Ranganathan (1998) Roy and Mandal (2001) Anand et al. (1999) Shanthi et al. (2003) Babu et al. (2000) Swain et al. (2003) Satyanarayana et al. (2000) Shanthi et al. (2004) Banumathy et al. (2003) Anand kumar et al. (2006) Bisne and Motiramani (2005) Gnana Sekaran et al. (2006) Panwar (2005) Raju et al. (2006) Sharma et al. (2006) Sanjeev Kumar et al. (2007) Venkatesan et al. (2007) Sarma et al. (2007) Yadav et al. (2007) Sharma and Mani (2008) Rahimi et al. (2010) Satheesh kumar et al. (2010) Padmavathi et al. (2012) 3. No. of productive tillers per plant Banumathy and Prasad (1991) Ganesan and Rangaswamy (1998) Vijaya lakshmi et al. (2008) Dhanakodi and Subramanian (1994) Manonmani and Ranganathan (1998) Vijayakumar et al. (1994) Anand et al. (1999) Ram et al. (1998) Babu et al. (2000) Gnana Sekaran et al. (2006) Satyanarayana et al. (2000) Satheesh kumar et al. (2010) Roy and Mandal (2001) Banumathy et al. (2003) Shanthi et al. (2003) Swain et al. (2003) Shanthi et al. (2004)

24 Table 2.1 (Cont.) Additive Non additive Additive and non additive Patil et al. (2003) Bisne and Motiramani (2005) Panwar (2005) Anand Kumar et al. (2006) Raju et al. (2006) Sarma et al. (2007) Yadav et al. (2007) Sharma and Mani (2008) Salgotra et al. (2009) Jayasudha and Sharma (2010) Kumar Babu et al. (2010) Saidaiah et al. (2010) Padmavathi et al. (2012) 4. Panicle length Banumathy and Prasad (1991) Anand et al. (1999) Vijaya lakshmi et al. (2008) Ghosh (1993) Babu et al. (2000) Pradhan and Singh (2008) Ram et al. (1998) Satyanarayana et al. (2000) Swain et al. (2003) Roy and Mandal (2001) Raju et al. (2006) Banumathy et al. (2003) Sarma et al. (2007) Shanthi et al. (2003) Shanthi et al. (2004) Bisne and Motiramani (2005) Panwar (2005) Anand Kumar et al. (2006) Dhakar and Vinit Vyas (2006) Gnana Sekaran et al. (2006) Sharma et al. (2006) Sanjeev Kumar et al. (2007) Venkatesan et al. (2007) Shukla and Pandey (2008) Salgotra et al. (2009) Jayasudha and Sharma (2010) Kumar Babu et al. (2010) Saidaiah et al. (2010) 5. Panicle weight Ram (1994) Ashfaq et al. (2013) 6. No. of filled grains per panicle Ganesan and Rangaswamy (1998) Anand et al. (1999) Ram et al. (1998) Babu et al. (2000) Shanthi et al. (2003) Satyanarayana et al. (2000) Swain et al. (2003) Reddy (2002) Shanthi et al. (2004) Banumathy et al. (2003) Anand Kumar et al. (2006) Patil et al. (2003) Satheesh kumar et al. (2010) Bisne and Motiramani (2005) Panwar (2005)

25 Table 2.1 (Cont.) Additive Non additive Additive and non additive Raju et al. (2006) Sharma et al. (2007) Sharma and Mani (2008) Salgotra et al. (2009) Saidaiah et al. (2010) Padmavathi et al. (2012) grain weight Ram et al. (1998) Anand et al. (1999) Pradhan and Singh (2008) Roy and Mandal (2001) Meenakshi and Devarathinam Reddy (2002) Babu et al. (2000) Shanthi et al. (2003) Satyanarayana et al. (2000) Swain et al. (2003) Banumathy et al. (2003) Shanthi et al. (2004) Panwar (2005) Anand Kumar et al. (2006) Dhakar and Vinit Vyas (2006) Gnana Sekaran et al. (2006) Sarma et al. (2007) Raju et al. (2006) Venkatesan et al. (2007) Sanjeev Kumar et al. (2007) Yadav et al. (2007) Satheesh kumar et al. (2010) Shukla and Pandey (2008) Umadevi et al. (2010) Kumar Babu et al. (2010) Gnanamalar et al. (2013a) Padmavathi et al. (2012) 8. Grain yield per plant Ganesan and Rangaswamy (1998) Babu et al. (2000) Roy and Mandal (2001) Ram et al. (1998) Satyanarayana et al. (2000) Sanjeev Kumar et al. (2007) Meenakshi and Devarathinam (1999) Reddy (2002) Vijaya lakshmi et al. (2008) Shanthi et al. (2003) Banumathy et al. (2003) Pradhan and Singh (2008) Shanthi et al. (2004) Patil et al. (2003) Gnana Sekaran et al. (2006) Swain et al. (2003) Satheesh kumar et al. (2010) Bisne and Motiramani (2005) Panwar (2005) Anand Kumar et al. (2006) Dhakar and Vinit Vyas (2006) Raju et al. (2006) Saravanan et al. (2006a) Sharma et al. (2006) Venkatesan et al. (2007) Yadav et al. (2007) Sharma and Mani (2008) Shivani et al. (2009) Sharma and Mani (2008) Shukla and Pandey (2008) Salgotra et al. (2009) Jayasudha and Sharma (2010) Kumar Babu et al. (2010) Saidaiah et al. (2010) Adilakshmi and Raghavareddy Padmavathi et al. (2012) Gnanamalar et al. (2013a)

26 Table 2.1 (Cont.) Additive Non additive Additive and non additive 9. Kernel length Raju et al. (2003) Saravanan et al. (2006a) Roy et al. (2012) Sharma et al. (2007) Sanjeev Kumar et al. (2007) Sharifi et al. (2009) Venkatesan et al. (2007) Umadevi et al. (2010) Gonya nayak et al. (2011) Asfaliza et al. (2012) Gnanamalar et al. (2013) 10. Kernel breadth Sharma et al. (2007) Saravanan et al. (2006a) Raju et al. (2003) Sharifi et al. (2009) Venkatesan et al. (2007) Sanjeev Kumar et al. (2007) Gonya nayak et al. (2011) Shivani et al. (2009) Roy et al. (2012) Asfaliza et al. (2012) Adilakshmi and Raghavareddy Gnanamalar et al. (2013) 11. Kernel L/B ratio Raju et al. (2003) Venkatesan et al. (2007) Sharma et al. (2007) Vijaya lakshmi et al. (2008) Sanjeev Kumar et al. (2007) Umadevi et al. (2010) Sharifi et al. (2009) Gonya nayak et al. (2011) Asfaliza et al. (2012) Roy et al. (2012) Gnanamalar et al. (2013) 12. Kernel length after cooking Umadevi et al. (2010) Shivani et al. (2009) Gnanamalar et al. (2013) Adilakshmi and Raghavareddy (2011) Gonya nayak et al. (2011) Roy et al. (2012) Gnanamalar et al. (2013) 13. Kernel elongation ratio Pradhan and Singh (2008) Shivani et al. (2009) Tyagi et al. (2010) Gonya nayak et al. (2011) Roy et al. (2012) 14. Head rice recovery Sharma and Mani (1998) Munhot et al. (2000) Shivani et al. (2009) Adilakshmi and Raghavareddy (2011) Gonya nayak et al. (2011) Gnanamalar et al. (2013)

27 Panwar (2005) studied the combining ability of parents and crosses in rice, and reported the importance of non-additive gene action controlling all the traits studied. The line IET and the testers Kasturi, Basmati 370, Pusa Basmati-1, Taraori Basmati and IR 64 were good general combiners for grain yield per plant. Fourteen cross combinations recorded significant sca effects for grain per plant. Singh and Lal (2005) recorded that the GCA and SCA were significant for all the seven characters indicating the importance of both additive and non-additive genetic components for these traits. The per se performance was observed to be a good indication of gca effects of the parents and sca effects of the crosses. Among the parents studied, Vaidehi and Rajshree were observed to be good general combiners for grain yield. The superior specific cross combinations Saket 4 x Vaidehi, Rajshree x Kamini, Prabhat x Rajshree and Sita x Vaidehi appeared promising for further exploitation in rice breeding programme. In line x tester interaction study, Anand Kumar et al. (2006) found that mean squares due to parent vs crosses differed significantly for majority of the traits. Among the CMS lines, IR 68886A for earliness and IR 58025A for yield and its component traits were found to be superior general combiners. Four testers viz., Pusa 1040, PSRM , RAU and RAU were rated as good general combiners for yield. The crosses IR 68886A x Pusa 1040, IR 58025A x RAU and IR 68886A / PSRM recorded significant heterosis for yield and yield contributing traits. Narasimman et al. (2007) revealed that ADT 44 was good general combiner for all the six traits studied. The parent CR 1009 was also observed to be good combiner for all the traits except harvest index. The cross ADT 4 x CR 1009 exhibited highly significant positive sca effects coupled with highly significant positive heterobeltiosis and standard heterosis for number of filled grains per panicle, biomass per plant and grain yield per plant. Sanjeev Kumar et al. (2007) reported significant gca and sca variances for all the characters indicating the importance of both additive and non-additive gene actions. However, preponderance of additive gene action was recorded for the grain length. Non-additive gene action was recorded for length of panicle and grain length. Parents HPR2047, VL and JD8 were good general combiners for grain yield and related characters. Among these, only five hybrids showed significant positive effects for grain yield/plant and other characters.

28 In a line x tester analysis by Sarial et al. (2007), two restorers Basmati 385 and HKR 241 were found to be good general combiners for grain yield / plant and 1000 grain weight, P 1037 for 1000 grain weight and effective tillers/plant while, Karnal local for 1000 grain weight. Among the CMS lines, IR 58025A and PMS 3A were characterized as good general combiners for grain yield and other traits. The specific cross combinations characterized with high significant sca effects were IR 58025A x Basmati 385, IR 62829A x Basmati 395, IR 62829A x HKR 241 and PMS 3A x P for grain yield/plant and effective tillers per plant, IR 62829A x Karnal local for 1000 grain weight. PMS 10A x SAP Khalsa 7 for days to 50 per cent flowering and PMS 3A x HKR 241 for primaries per panicle. The gca effects of the parents were not reflected in the sca effects of the crosses. Sarma et al. (2007) observed that additive genetic variance was higher in magnitude for plant height, panicle length and all other quality parameters. Nonadditive gene action on the other hand was predominant for grain yield and its components viz., effective tillers, panicle weight and grain weight. Combining ability study by Venkatesan et al. (2007) revealed non- additive gene action governing the characters viz., days to first flower, plant height and grain yield per plant. Predominance of GCA variance was recorded for days to first flower, plant height and grain yield per plant. Among the parents, the lines AD 25137, AD and MDU 5 and testers ADT 36, ADT 36, ADT 43 and IR 50 were good combiners for grain yield and most of the other components studied. Bansal et al. (2008) assessed heterosis and combining ability effects in an 11parent diallel cross involving 8 scented and 3 non-scented rice stocks. Maximum heterosis for grain yield per plant was obtained in the cross of Karnal Local, a high quality scented rice and a semi-dwarf scented parent, Dawag. The estimates of GCA and SCA indicated predominance of non-additive gene effects for days to flowering, plant height, panicle length, tillers per plant, number of fertile tillers per plant, grain yield per plant, 1000-grain weight and length to breadth ratio. The study suggested that a greater number of favourable genes combined in one genotype to obtain maximum yield without loss in quality characteristics from crosses involving good combining scented parents like Karnal Local, Basmati 1, Basmati 372 selection, and Bindli semidwarf mutant which will prove extremely useful in generating high-yielding dwarf aromatic rices through careful selection for quality traits and yield.

29 Pradhan and Singh (2008) studied 30 hybrids generated from crossing three lines with ten testers. The gca and sca effects were significant for all the characters, indicating the importance of both additive and non additive genetic components. But it was found that there was predominance of non-additive genetic components for expression of different traits. Among the parental lines, RP and RP were best general combiners for grain yield along with other traits. The most specific combiners for grain yield and other traits were Pusa3A x RP , IR 68281A x BTCE 10-98, IR 58025A X HKR , Pusa x RP and IR68281A x RP Dalvi and Patel (2009) studied sixty hybrids along with parents for 13 yield attributing characters. Among the male parental lines, BR RTN-3, IR-46 appeared the best general combiner for grain yield and most of the component characters. The female line IR-58025A was found to be good general combiner for all the traits except plant height and L/B ratio of grain. Shivani et al. (2009a) stated that, eighteen indica/indica hybrids developed by crossing three lines with six testers were screened for various grain quality traits to assess the combining ability of the parents. For head rice recovery, the crosses involving IR 58025A with MTU 9992 and KMR-3, IR 62829A with MTU 9992 and IR 68886A with IR 40750R and IR showed significant positive specific combinig ability (sca) effects. For kernel length, IR 58025A and IR A among lines and MTU 9992 and IR among testers showed positive significant general combining ability (gca) effects. The magnitude of σ 2 gca/σ 2 sca revealed the predominance of nonadditive genetic variance for most of the quality characters. Muhammad et al. (2010) studied the heritability, genetic advance and heterosis on 27 F 1 hybrids and their 12 basmati parents to assess combining ability of morphophysiological traits for identifying the suitable parental genotypes and hybrids. Preponderance of non-additive gene effects was realized by higher value of SCA compared to GCA, ratio of variance of GCA to SCA and degree of dominance. Based on SCA effects of the hybrids in relation to GCA effects of parents, Kashmir Basmati X Basmati-385 is recommended for recombination breeding with early selection of desired plants whereas DM X Basmati-385 and Super Basmati X Basmati-385 were proposed for postponement selection of superior genotypes until advanced generations.

30 Kumar Babu et al. (2010) studied 96 hybrids generated from crossing four CMS lines and twenty four testers along with parents for combining ability for quality characters. Predominance of non-additive gene action was observed for grain length, L/B ratio. The line IR58025A and tester MTU 1010 II were found to be good general combiners for grain quality characters. Two crosses PMS10A X MTU II and PMS10A X MTU II were identified as most promising for yield based on sca effects, per se performance and with more than 55 per cent standard heterosis. A line x tester analysis was made by Satheesh Kumar et al. (2010) in rice with seven ovule parents and four pollinator parents to identify suitable general and specific combiner for breeding program. Dominant type of gene action for all the six traits namely, days to 50 percent flowering, plant height, number of productive tillers per plant, number of grains per panicle, hundred grain weight and grain yield per plant was observed. Parents JAYA and CRAC were good general combiners for grain yield per plant and most of the yield traits. The cross combinations CRAC x JAYA and IR B-3R-B-24-3 X JAYA were the best specific combiners for grain yield per plant. Tyagi et al. (2010) studied nine lines, three testers and 27 hybrids. Among the lines, Taraori Basmati, Shah-Pasand and Pusa-1121 were found to be good general combiners for aroma. Cross between Basmati-370 x Heibao was found to be good specific combiner for aroma and cross P-1463 x P-44 expressed high sca effects for aroma. Sixteen crosses developed from four aromatic lines and four normal testers were evaluated for various grain quality traits to assess the combining ability of the parents and to identify best combinations by Gonya nayak et al. (2011). The predominance of non-additive genetic variance was noticed for most of the quality characters viz., milling and head rice recovery, kernel length and breadth after cooking, kernel elongation ratio and aroma. Kernel length, kernel breadth and L/B ratio were under the influence of additive gene action. Parents Yamini, Pusa-1121 and MTU-1010 appeared to have contributed maximum favourable genes for physical traits and cooking. These parents can be widely used in crossing programmes to improve quality of normal rice genotypes. Cross RNR-2354 x MTU-1081 was found to be good specific combiner for head rice recovery, kernel length, kernel breadth and L/B ratio. Cross RNR-2354 x BM - 71 was found to be good specific combiner for kernel length after cooking, kernel

31 elongation ratio and aroma. Pusa x BM-71 was found to be good specific combiner for kernel length and L/B ratio. Estimation of GCA, SCA and reciprocal by Asfaliza et al. (2012) indicated the important role of additive or non-additive gene effect or both for the parents and the progenies derived from a 7 7 full diallel crosses. The mean square values of SCA revealed significant differences for the GCA for the entire grain quality traits and nonsignificant for AMYL, GC, GL, GW, MGL and LW. The specific combining ability effects were significant for several populations derived from crosses involving MR 263, MR 267, MRQ 74, Q 85 and MRQ 76. Padmavathi et al. (2012) reported highly significant sca variances for all the characters indicating the importance of non-additive gene actions. CMS line, APMS 10A recorded high significant gca effects for number of tillers per palnt, panicle length and test weight in addition to grain yield per plant. Five crosses possessed only one parent with significant positive gca effects indicating the involvement of additive and dominance genetic interaction. Whereas IR58025A x MTU II cross had both parents with low gca effects for grain yield per plant indicating over dominance and epistatic interactions. Gnanamalar and Vivekanandan (2013a) studied seven high yielding rice genotypes viz., ADT 41, ADT 46, CO 47, TKM 9, Jeeragasamba, ACM and AS90033 and their 21 crosses that were effected in a half diallel fashion (excluding reciprocals). The combining ability studies for grain yield and grain quality analysis revealed predominance of additive genetic variance wasobserved for hundred grain weight, kernel length, kernel L/B ratio and kernel length after cooking whereas nonadditivegenetic variance was greater for grain yield, hulling percentage, milling percentage, head rice recovery, kernel breadth, linear elongation ratio, water uptake, volume expansion ratio, alkali spreading value, amylase content and gel consistency suggesting the postponement of selection to later generation from the segregating population in pedigree breeding programme.

32 2.2 HETEROSIS AND INBREEDING DEPRESSION Heterosis is expressed as percentage increase or decrease of F 1 hybrid over the mid parental value. The superiority of F 1 hybrid over the better parent is known as heterobeltiosis, while F 1 superiority over the standard check is termed as standard heterosis. Non allelic interaction might be the cause of heterosis rather than the special relation between the genes at same locus (Jinks, 1955). Falconer (1960) explained heterosis as reverse phenomenon to inbreeding depression. Heterosis is directly proportional to Σdy2 where, d is the degree of dominance component of gene action and y is the difference in the gene frequencies of the parents involved in the cross. The success of heterosis in breeding depends on the amount of genetic diversity present in the material. In rice, heterosis was first reported by Jones (1926) who observed that some F 1 hybrids had more culms and higher yield than their parents. Since then, several rice researchers also confirmed its occurrence for yield and yield contributing characters (Virmani, 1994). However, most of these reports were on relative heterosis and heterobeltiosis and are not on standard heterosis. It was only after the successful development and cultivation of F 1 rice hybrids in China since 1976, the standard heterosis useful in commercial agriculture is being considered. Pertinent literature available on heterosis in rice has been reviewed and summarized in Table 2.2.

33 Table 2.2. Review of literature on heterosis and inbreeding depression for various traits in rice Number Range of heterosis per cent over of Inbreeding Reference crosses Mid parent Better parent depression studied Days to 50 per cent flowering to to Ram (1992) to to to Ganesan et al. (1997) to Mishra and Pandey (1998) to to Ghosh (2002) to Bhawana Joshi et al. (2004) to to Verma et al. (2004) to Yadav et al. (2004) to Bhandarkar et al. (2005) to to Aananthi and Jebaraj (2006) to to Pandya and Tripathi (2006) to to Raju et al. (2006) to to Saravanan et al. (2006b) to Shanthala et al. (2006) to 47 - Singh et al. (2006a) to to Anjuchaudhary et al. (2007) to to Deoraj et al. (2007) to Sanjeev Kumar et al. (2007b) to -2 Eradasappa et al. (2007) to 13.6 Rosamma and Vijayakumar (2007) to to to Borah and Barman (2010) to to to Gouri Shankar et al. (2010) to Sanjeev Kumar et al. (2010) to to Palaniraja et al. (2010) to to Krishna et al. (2011) to Patil et al. (2011) to Satheeshkumar and Saravanan (2011) to to Vanisree et al. (2011) to to Rajender reddy et al. (2012) to Sharma et al. (2013) to to Dey et al. (2013)

34 Table 2.2 (Cont.) Plant height to to to Ananda Kumar and Sreerangaswamy (1986) to to Ram (1992) to to to Reddy and Nerkar (1995) to to 2.93 Reddy (1996) to to to 4.00 Ganesan et al. (1997) to Mishra and Pandey (1998) to to Tiwari and Sarathe (2000) to to 5.20 Ghosh (2002) to to to Alam et al. (2004) to Bhawana Joshi et al.., (2004) to to Verma et al. (2004) to Yadav et al. (2004) to Bhandarkar et al. (2005) to to Aananthi and Jebaraj (2006) to Pandya and Tripathi (2006) to to Raju et al. (2006) to to Saravanan et al. (2006b) to Shanthala et al. (2006) to 47 - Singh et al. (2006a) to Singh et al. (2006b) 5-12 to to Anjuchaudhary et al. (2007) to to Deoraj et al. (2007) to Sanjeev Kumar et al. (2007b) to Eradasappa et al. (2007) to 34.4 Rosamma and Vijayakumar (2007) to to to Borah and Barman (2010) to to to 2.06 Gouri Shankar et al. (2010) to to Palaniraja et al. (2010) to to Krishna et al. (2011) to Patil et al. (2011) to Dey et al. (2013) to to Sharma et al. (2013)

35 Table 2.2 (Cont.) No. of productive tillers per plant to to Ram (1992) to to to Reddy and Nerkar (1995) to to to Ganesan et al. (1997) to Mishra and Pandey (1998) to Singh and Haque (1999) to to Ghosh (2002) to to to Alam et al. (2004) to Bhawana Joshi et al. (2004) to to Verma et al. (2004) to Yadav et al. (2004) to Bhandarkar et al. (2005) to to Aananthi and Jebaraj (2006) to to Pandya and Tripathi (2006) to to Raju et al. (2006) to to Saravanan et al. (2006b) to Shanthala et al. (2006) to 64 - Singh et al. (2006a) to to Singh et al. (2006b) to to Deoraj et al. (2007) to Narasimman et al. (2007) to to to Gouri Shankar et al. (2010) to to Palaniraja et al. (2010) to to Krishna et al. (2011) to Patil et al. (2011) to Satheeshkumar and Saravanan (2011) to to Vanisree et al. (2011) to to Rajender reddy et al. (2012) to to Ashfaq et al. (2013) to Dey et al. (2013) to to Sharma et al. (2013)

36 Table 2.2 (Cont.) Panicle length to to to Ananda Kumar and Sreerangaswamy (1986) to to to Reddy and Nerkar (1995) to to-1.56 Reddy (1996) to to to 8.00 Ganesan et al. (1997) to Mishra and Pandey (1998) to to Ghosh (2002) to to to Alam et al. (2004) to Bhawana Joshi et al. (2004) to to Vanaja and Babu (2004) to to Verma et al. (2004) to Yadav et al. (2004) to Bhandarkar et al. (2005) to to Aananthi and Jebaraj (2006) to to Pandya and Tripathi (2006) to to Raju et al. (2006) to Shanthala et al. (2006) to 34 - Singh et al. (2006a) to to Deoraj et al. (2007) to Sanjeev Kumar et al. (2007) to Singh et al. (2007) to to to Borah and Barman (2010) to to to Gouri Shankar et al. (2010) to to Palaniraja et al. (2010) to to Krishna et al. (2011) to Patil et al. (2011) to to Vanisree et al. (2011) to to Dey et al. (2013) to Sharma et al. (2013) 5. Panicle weight to to Islam et al. (2010) to to Vanisree et al. (2011) to to Ashfaq et al. (2013) to to Krishna et al. (2011)

37 Table 2.2 (Cont.) No. of filled grain per panicle to to Ram (1992) to to to Reddy and Nerkar (1995) to to38.17 Reddy (1996) to to to Ganesan et al. (1997) to to Annadurai and Nadarajan (2001) to to to Alam et al. (2004) to Yadav et al. (2004) to to Aananthi and Jebaraj (2006) to to Raju et al. (2006) to 71 - Singh et al. (2006a) to Singh et al. (2006b) to to Deoraj et al. (2007) to Narasimman et al. (2007) to Singh et al. (2007) to to to Borah and Barman et al. (2010) to to Palaniraja et al. (2010) to Satheeshkumar and Saravanan (2011) to to Vanisree et al. (2011) to Ashfaq et al. (2013) to Dey et al. (2013) to to Sharma et al. (2013) grain weight to to to 4.92 Reddy and Nerkar (1995) to to 7.24 Reddy (1996) to to to 8.00 Ganesan et al. (1997) to Vishwakarma et al.(1998) to to Sathya et al. (1999) to to Annadurai and Nadarajan (2001) to to to Alam et al. (2004) to Bhawana Joshi et al. (2004) to to Vanaja and Babu (2004) to to Verma et al. (2004) to to Aananthi and Jebaraj (2006) to to Pandya and Tripathi (2006)

38 Table 2.2 (Cont.) to to Raju et al. (2006) to to Saravanan et al. (2006b) to Shanthala et al. (2006) to 48 - Singh et al. (2006a) to Singh et al. (2006b) to to Deoraj et al. (2007) to Narasimman et al. (2007) to Sanjeev Kumar et al. (2007) to Singh et al. (2007) to to Krishna et al. (2011) to Patil et al. (2011) to Patil et al. (2011) to Satheeshkumar and Saravanan (2011) to to Vanisree et al. (2011) to Ashfaq et al. (2013) to Dey et al. (2013) to to Sharma et al. (2013) 8. Grain yield per plant to Mishra and Pandey (1998) to to Anand et al. (1999) to Singh and Haque (1999) to to Tiwari and Sarathe (2000) to to Ghosh (2002) to to to Alam et al. (2004) to Bhawana Joshi et al. (2004) to to Vanaja and Babu (2004) to to Verma et al. (2004) to Yadav et al. (2004) to Bhandarkar et al. (2005) to Anand Kumar et al. (2006) to to Aananthi and Jebaraj (2006) to to Pandya and Tripathi (2006) to to Raju et al. (2006) to to Saravanan et al. (2006b) to Shanthala et al. (2006)

39 Table 2.2 (Cont.) to to Sharma et al. (2006) to152 - Singh et al. (2006a) to Singh et al. (2006b) to to Anjuchaudhary et al. (2007) to to Deoraj et al. (2007) to to Narasimman et al. (2007) to 5.59 Sanjeev Kumar et al. (2007) to 69 - Singh et al. (2007) to to to Borah and Barman et al. (2010) to to to Gouri Shankar et al. (2010) to to65.32 Sanjeev Kumar et al. (2010) to to Palaniraja et al. (2010) to to Krishna et al. (2011) to Patil et al. (2011) to Satheeshkumar and Saravanan (2011) to to Vanisree et al. (2011) to Rajender reddy et al. (2012) to to Ashfaq et al. (2013) to Dey et al. (2013) to to Sharma et al. (2013) 9. Kernel length to to Raju et al. (2003) to to Pandya and Tripathi (2006) to to Saravanan et al. (2006b) to Sanjeev Kumar et al.(2007) to to Krishna et al. (2011) to to Rajender reddy et al. (2012) 10. Kernel breadth to to Raju et al. (2003) to Pandya and Tripathi (2006) to to Saravanan et al. (2006b) to Sanjeev Kumar et al. (2007) to to Krishna et al. (2011) to to Rajender reddy et al. (2012)

40 Table 2.2 (Cont.) Kernel L/B ratio to to Raju et al. (2003) to Sanjeev Kumar et al. (2007) to to Krishna et al. (2011) to Patil et al. (2011) to Satheeshkumar and Saravanan (2011) to to Ashfaq et al. (2013) to to Rajender reddy et al. (2012) 12. Kernel length after cooking to to Gnanamalar and Vivekanandan (2013b) 13. Kernel elongation ratio to Sarawgi et al. (2000) to Gnanamalar and Vivekanandan (2013b) 14. Head rice recovery to to Raju et al. (2003) to to Pandya and Tripathi (2006) to to Gnanamalar and Vivekanandan (2013b) to Sharma et al. (2013)

41 2.3 GENERATION MEAN ANALYSIS The inheritance of quantitative traits is a moving target. The expression of these traits is affected not only by large number of genes governing them but also by environmental effects. Frequently, these genes interact with each other causing distortions in Mendelian ratios and leading to novel phenotypes (Phillips, 1998). The term epistasis was coined by Bateson (1909) to describe a situation where in action of one gene masks the effect of other much like the phenomenon of complete dominance in which on allele at a locus mask the effect of other. The estimation of epistasis assumes more significance in view of the fact that in its presence, variance component estimates are likely to be biased hence inferences drawn from such estimates are more likely to be misleading. The magnitude of the bias depends upon the relative magnitude of epistatic effects comparatively to the deviation of d and h, type of prevailing epistasis and direction of dominance. The existence of large array of interactions in a polygenic system cause over-estimation or underestimation of heritability estimates (narrow sense) thereby causing additional bias in predicted gains. Generation mean analysis is a powerful statistical procedure for detection of epistasis using several basic generations from a cross between two inbred lines. The literature pertaining to the generation mean analysis and epistasis is summarized below. Generation mean analysis revealed that for most families, the traits grain yield, plant height and panicle length were genetically controlled by additive and dominance gene effects, although non-allelic gene interactions were observed in some cases. The degree dominance in most of the families indicated the predominance of dominant and over dominant gene effects for full or empty grains per panicle (Honarnejad and Tarang, 2001). Hasib et al. (2002) studied parental F 1, F 2, BC 1, and BC 2 generations of five crosses involving induced mutants and basmati rice varieties for days to 50 percent flowering, plant height, panicle number per plant, panicle length, spikelet fertility per cent, grain length, length / breadth ratio, test weight and grain yield per plant. Epistasis was noticed in the majority of characters for all crosses. Both additive and non-additive gene effects were important for the inheritance of almost all the characters under study. The mean values of number of filled grains per panicle, spikelet fertility and grain yield of P 1, P 2, F 1, F 2, B 1 and B 2 of four cross combinations were subjected to

42 genetic analysis through generation mean analysis by Banumathy and Thiyagarajan (2005). A simple three parameter model was adequate for the variability in respect of days to 50 percent flowering, panicle length per plant and grain length. Among the digenic interaction models both five and six parameter models were fitted for almost all the characters. The dominant effects were more important than the additive effects in most of the crosses. The duplicate type of epistasis was present with the exception of panicle length in cross Muskbudhi x Ratna in which the complementary type of epistasis was evident. Murugan and Ganesan (2006) studied six crosses which involved IR 58025A as a common female parent and six testers viz., IR 72, IR 24, Daunsan, ARC 11353, IR and IET and reported that, two traits productive tillers per plant and panicle length were predominantly influenced by additive gene effects and interaction component of [j] and [l] along with duplicate epistasis. The traits filled grains per panicle and hundred grain weight were controlled by dominant gene action and among interactions [i] and [j] effects were influenced these traits along with duplicate gene actions. Grain yield per plant was predominantly under the control of dominance and interaction components [i], [j] and [l] along with duplicate type of gene action. Patil et al. (2006a) reported that, mean, additive [d] and X 2 test was highly significant and positive in entire cross combination studied and dominance effects [h] were positively significant in all the crosses except Pei ai 64S x C-20 (-11.20) for days to 50 percent flowering. Productive tillers per plant showed negative significant additive [d] genes effect and significant and positive dominance [h] genes effect in all crosses except IR x C-20. The additive [d] and dominance gene effects were significant and positive in TGMS-18 x C-20, IR x C-20, IR x C-20 and TGMS-18 x ADT-36 for grains per panicle. In 1000 grain weight, the additive [d] and dominance [h] effects coupled with significant values of mean and χ 2 test showed significant differences in all the crosses with duplicate gene action. The mean effects of grain yield per plant coupled with dominance [h] gene effects and χ 2 test were significant and positive in all the crosses. The positive and significant additive [d] gene effect was also recorded in grain yield per plant. Estimation of the genetic effects on the assumption of the presence of digenic interaction in six F 1 hybrids was studied by Patil et al. (2006a). Population was developed for six generations such as P 1, P 2, F 1, F 2, BC 1 and BC 2 to study the genetically control of a trait and the involvement of gene action (m, d, h, i, j and l).

43 Hybrids showed significant differences in epistatic properties of the genes and involvement of digenic model and good fit for complementary and duplicate gene action. Trait under study showed good fitness for complementary gene action (productive tillers per plant and 1000 grain weight) and involvement of duplicate gene action (grains per panicle and grain yield per plant). In case of productive tillers, both [h] and [l] have negative sign and are of lower magnitude, it reflects mainly complementary interaction between dominant decreasing genes. Whereas, 1000 grain weight showed positive and higher magnitures for [h] and [l] components, it will indicate mainly complementary interaction between increasing genes. Trait days to 50 percent flowering failed to show good fitness of digenic model could result from presence of higher order interaction like trigenic and other higher order interactions or linkage between pairs of interacting loci. The investigation was taken up by Verma et al. (2006) to study the nature and magnitude of gene effects for yield and its components in Jhona 9349/IET and Narendra 80/Lalmati crosses based on six parameter model. Results revealed that the predominant role of dominance and epistasis was obtained for grain yield, tillers per plant, grains per panicle and 1000 grain weight in both the crosses. Additive and dominance effects were important for plant height and panicle length. Among the digenic interactions, additive x additive and dominance x dominance effects contributed more in majority of the characters. Additive x dominance gene effect was also significant for all the traits in both the crosses. In general, duplicate non-allelic interaction was observed for most of the yield contributing characters. Nayak et al. (2007) studied parental, F 1, F 2, BC 1, and BC 2 generations of four crosses involving scented and non-scented rice varieties for days to 50 percent flowering, plant height, panicle number per plant, panicle length, number of grains per panicle, 1000 grain weight, grain length, length / breadth ratio and grain yield per plant. A simple three parameter model was adequate for the variability in respect of days to 50 percent flowering, panicle length per plant and grain length. Among the digenic interaction models both five and six parameter models were fitted for almost all the characters. The dominant effects were more important than the additive effects in most of the crosses. The duplicate type of epistasis was present with the exception of panicle length in cross Muskbudhi x Ratna in which the complementary type of epistasis was evident. The seven generations (P 1, P 2, F 1, F 2, F 3, B 1, B 2 ) of the three crosses viz., SBIR M x Rajshree, SBIR M x Rajshree and SBIR

44 M x Rajshree were evaluated under normal transplanting (NTP) and delayed transplanting (DTP) by Sing et al.(2007) by employing simple and joint scaling test and six parameter model of generation mean analysis to study nature and magnitude of gene effects. Simple and joint scaling tests indicated presence of epistatic interaction and fitness of digenic interaction model. Six parameter model of generation mean analysis revealed importance of additive [d] and dominance [h] gene effects as well as one or more epistatic gene interaction [l]. Thirugnana Kumar et al. (2007) studied five generations (P 1, P 2, F 1, F 2 and F 3 ) of six rice crosses for estimating the nature and magnitude of gene effects for grain yield and its component characters. The scaling tests indicated that the scales C and D were significant for all the six characters in all the crosses studied. The results indicated the importance of duplicate dominant epistasis for number of productive tillers, number of filled grains and 1000 weight. For biomass, grain yield and harvest index complementary recessive epistasis was found to be important. Anil Kumar and Mani (2010) studied the components of genetic variance for grain yield, yield components and certain quality traits in seven crosses among eight basmati parental lines. The character means over six generations were subjected to scaling test. In the presence of epistasis, six parameter model was used to detect epistasis. The genetic analysis revealed the importance of additive components (d) for plant height, no. of filled grains/panicle, panicle length, 1000 grain weight and kernel elongation ratio; dominance (h) and epistatic components for grain yield per plant, 1000 grain weight, panicle length, no. of filled grains/panicle in most of the crosses. Dominance effect was important for kernel L/B ratio. Among the digenic interactions additive x additive (i) and dominance x dominance (l) effects contributed more for most of the characters. Additive x dominance (j) gene effect was important for 1000 grain weight in four crosses; for grain yield per plant in two crosses. In general, the crosses revealed duplicate type non-allelic interactions for grain yield per plant. Based on the nature of combining ability inferred from line x tester analysis, three cross combinations viz., TS29/ADT41, TS29/Pusa Basmati 1 and TS29 / Basmati 370 were selected for generation mean analysis study by Mahalingam and Nadarajan (2010). The scaling tests indicated the presence of epitasis for all the characters and six parameter model was followed to estimate the various gene actions. In TS29/Basmati 370 cross combination all the three scales are positively significant. The mean effect m was significantly positive and greater than all other effects in all the three crosses for kernel breadth, kernel length after cooking, volume expansion ratio, alkali spreading

45 value, gel consistency and amylase content. The additive x dominance effect (j) was positive and significant for kernel length after cooking, linear elongation ratio, gel consistency and amylose content in the crosses TS29/ADT41, TS29/Pusa Basmati 1 and TS29/Basmati 370. In general, both additive and non-additive gene effects appear to all eight characters studied. Therefore, improvement of these traits appears to beset with difficulties as simple selection techniques will not be able to fix superior lines in the early segregating generations. Postponement of selection of superior lines to later generations in pedigree breeding will be effective. Thirugnanakumar et al. (2011) studied parental F 1, F 2, and F 3 generations of six crosses involving three parents with three different durations for days to flowering, number of productive tillers per plant, number of filled grains per panicle, 100 seed weight, grain L/B ratio, grain yield per plant and harvest index. The distribution pattern of the segregating generations revealed that, the F 3 s of the cross ADT 38 x ADT 37 for hundred seed weight and the F 3 s the cross ADT 38 x ADT 44 for grain yield per plant showed normal symmetrical distribution. The kurtosis value was almost negligible indicating mesocurtic nature of the distribution. The F 3 s of ADT 38 x ADT 44 recorded high mean coupled with higher coefficient of variation, indicating the presence of additive genetic control. The higher mean performance in F 3 may be due to accumulation of favourable genes. All the other crosses and generations showed asymmetric distribution in positive as well as negative direction, for almost all the characters of interest. The mean was comparatively higher but the coefficients of variation were comparatively lower, indicating the preponderance of non-additive genetic control in the expression of the traits of interest. It is better to resort to intermating of segregants followed by recurrent selection for further improvement. Parental, F 1, F 2, BC 1 and BC 2 generations of five crosses involving indigenous aromatic rice cultivars were subjected to generation mean analysis to study the genetics fo seven yield and yield components by Srivastava et al. (2012). It was observed that h, i and l were significant for all the yield traits studied except h for 1000 grain weight and i and l for plant height. Aslo d was significant for all the yield components except plant height and yield/plant. Further j was significant for plant height and main panicle length. Thus for all the yield traits, additive and dominance gene effects as well as epistatic interactions were present indicating complex inheritance of the traits. This necessitates improvement of individual characters separately based on the nature of gene action. Exploitation of additive gene effect should be carried out following pedigree method of selection. For crosses and

46 characters where both additive and non-additive gene effects were important, single plant selection can be postponed and biparental mating could be followed wherein a few cycles of crossing of promising segregants in F2 and onwards would help in the incorporation of desirable genes into a single genetic background. Diallel selective matig or reciprocal recurrent selection will be helpful in simultaneously exploiting both kinds of gene effects for improving the trait. Kiani et al. (2013) studied 10 different populations (generations) including P 1, P 2, F 1, RF 1, BC 1, RBC 1, BC 2, RBC 2, F 2 and RF 2 generations of two crosses and additive dominance model was significant for traits in both crosses (except panicle length trait in Sang-e-Tarrom Gerdeh cross). The join scaling test indicated that the inheritance of traits related to yield was described by additive dominance components, non-allelic interactions mainly Additive Additive and additive dominance and duplicate epistasis. More than one major gene group appeared to be involved for the expression of 1000-grain weight and plant height while the remaining traits showed the presence of at least one major group of genes controlling their inheritance Genetic components of variance for yield and yield contributing traits were carried out by dusing 8 x 8 diallel mating design excluding receprocals by Kumar Aditya et al. (2013). Results revealed that both additive and non-additive gene effects were important for the inheritance of characters studied with preponderance of later for all traits, except 1000 grain weight, kernel breadth, kernel L/B ratio, content of amylose and alkali spreading value. The significance of gene distribution indicated the presence of gene asymmetry except for panicle length. High-narrow sense heritability further supported the importance of additive gene effects for 1000 grain weight, kernel breadth, kernel L/B ratio, content of amylose and alkali spreading value. Since non-additive / dominance components were higher than the additive for most of the characters in F 1 generation, biparental matign and/or reciprocal recurrent selection could be used for genetic improvement of these characters. Analysis of generation mean was carried out in six crosses of rice viz., ADT 41 / ADT 46, ADT 41 / CO 47, ADT 41/TKM 9, ADT 41/ Jeeragasamba, ADT 41/ACM and ADT 41/AS for hulling percentage, milling percentage, head rice recovery, kernel length, kernel breadth, kernel L/B ratio, kernel length after cooking, linear elongation ratio and alkali spreading value by Gnanamalar and Vivekanandan (2013c). The scaling test showed the presence of epistatic interactions for all the nine grain quality traits studied. Milling percentage and linear elongation ratio were governed by additive,dominance and epistatic interactions of additive x additive,

47 dominance x dominance and duplicate epistasis. Hulling percentage was governed by additive, dominance and duplicate type. Head rice recovery was under the control of additive, dominance, dominance x dominance and duplicate epistasis. Kernel length and kernel breadth were predominantly under the control of additive, dominance, additive x dominance and duplicate gene interactions. Kernel L/B ratio and kernel length after cooking were influenced by additive, additive x dominance and duplicate type. Dominance, additive x additive and duplicate type of gene actions influenced alkali spreading value. The other four grain quality traits viz., water uptake, volume expansion ratio, amylose content and gel consistency were under the control of non-additive gene action. To explore both additive and non-additive type of gene action it was suggested to postpone the selection to later generation in pedigree breeding programme. 2.4 GENTETIC STUDIES IN F 2 GENERATION (VARIABILITY, HERITABILITY AND GENETC ADVANCE) Estimates of the amount of variability for different characters and its heritable components available in the population are essential for dynamic plant breeding programmes. Crop improvement for grain yields has been achieved in rice through effective use of F 2 and further segregating generations and fixing desirable combinations. Grain yield is a complex trait and is the result of interaction of many variables. Therefore, selection of the plant types with characteristics directly associated with yield increase and highly heritable and fixable need to be identified before applying selection pressure. It becomes necessary to split the overall variability into heritable and nonheritable components with the help of certain genetic parameters. Heritability (narrow sense) estimates along with genetic advance in F 2 populations are of much help in predicting the resultant effect form selecting the best genotypes. Information in these lines is reviewed below in tabular form (Table 2.3).

48 Table 2.3. Review of literature on variability, heritability and genetic advance for various traits in rice Character Material studied Variability Heritability Genetic advance as Reference per cent mean Days to 50% F 2 Low High Low- Marimuthu et al.(1990) flowering Moderate Low High Low Prasanthi (1993) Low High Low Chookar et al. (1994) F 2 Low High Low Ganesan and Subramaniam (1994) - high Moderate Rao and Shrivastav (1994) Low Moderate Low Chauhan (1996) F 2 Low High Moderate- Ganeshan et al.(1996) Low Moderate - - Manonmani et al. (1996) F 3 - Medium High Sahdev Singh et al. (1996) - Medium High Singh and Chaudhary (1996) F 4 Low High Low Nath and Talukdar (1997) Moderate High High Vange and Ojo (1997) Low High Low Balan et al. (1999) Moderate High - Chikkalingaiah et al. (1999) High - - Kaw et al. (1999) Low high Low- Niranjana Murthy et al. (1999) moderate High - - Awasthi and Pandey (2000) - High High Madhavilatha et al. (2002) Low High High Nayak et al. (2002) Low High Low Patil et al. (2003) Low High Low Sinha et al. (2004) - High Low Madhavilatha et al. (2005) Low High Low Suman et al. (2005) - High High Sankar et al. (2006) - High High Bharadwaj et al.(2007) - High High Kishore et al. (2008) Low High Low Krishna et al. (2008) Moderate High Low Ashok kumar tuwar et al. (2013) Low High Moderate Sangam Kumar Singh et al. (2011) High High Moderate Venkata Subbaiah et al. (2011) Low High Low Akinwale et al. (2011) Low High Low Manoj kumar et al. (2011) Moderate High High Ravindrababu et al. (2012) Low High Moderate Pawan saini et al. (2013) Low High Moderate Rajesh Kumar Dhanwani et al. (2013) High High High Vanisree et al. (2013) Plant height F 2 Low High Low - Marimuthu et al.(1990) moderate - Moderate Moderate Reddy and Nerkar (1991) Low Remabai et al. (1992) Low High Low Chaubey and Singh (1994) Low High Mod - high Chookar et al. (1994) F 2 Moderate High High Ganesan and Subramaniam (1994) F 2 - High- High Murthy (1994) moderate moderate Moderate Moderate Low Chauhan (1996) F 2 Moderate High High Ganeshan et al.(1996) Moderate - - Manonmani et al. (1996)

49 Table 2.3 (Cont.) Moderate High Moderate Reddy and De (1996) F 3 - Low high Low Sahdev Singh et al. (1996) P+ F 1 +F 2 Moderate High Moderate Singh and Chowdhary (1996) F 4 High High Moderate Nath and Talukdar (1997) Moderate High High Vange and Ojo (1997) - High - Mokate et al.(1998) Low High - Chikkalingaiah et al. (1999) - High - Kaw et al. (1999) high High Moderate Niranjana Murthy et al. (1999) High - - Tripathi et al. (1999) High - - Awasthi and Pandey (2000) Moderate High High Nagajyothi (2001) Moderate - - Tara Satyavathi et al. (2001) - High High Venkata Suresh ( 2001) Moderate High High Nayak et al. (2003) Low High Moderate Patil et al. (2003) Moderate low High High Moderate Sinha et al. (2004) low - high Moderatehigh Suman et al. (2005) - High High Patra et al. (2006) - High High Sankar et al. (2006) - High High Bharadwaj et al.(2007) - High High Ashok kumar tuwar et al. (2013) Moderate - - Karad and Pol (2008) Moderate - High High Krishna et al. (2008) High High High High Kumar and Ramesh (2008) Moderate High High Akinwale et al. (2011) High High Moderate Manoj kumar et al. (2011) Low High Moderate Sangam Kumar Singh et al. (2011) High High Moderate Venkata Subbaiah et al. (2011) Moderate High High Ravindrababu et al. (2012) Moderate High High Pawan saini et al. (2013) Low High Moderate Rajesh Kumar Dhanwani et al. (2013) High High High Vanisree et al. (2013) Productive tillers per plant - High Low Ravindranadh et al. (1982) - Low Low Ramesh Kumar (1989) F2 High High High Marimuthu et al. (1990) F2 - High High Reddy and Nerkar (1991) Low Moderate Low Prasanthi (1993) High High High Chaubey and Singh (1994) High High Moderate Chookar et al. (1994) F2 High Moderate High Ganesan and Subramaniam (1994) F2 - High High Ganeshan et.al. (1996) High - - Manonmani et al. (1996) low low low Reddy and De (1996) F2 Low High High Srivastava and Shukla (1996) F4 - High moderate Nath and Talukdar (1997) Moderate - - Vange and Ojo (1997) F2 low High High Thakur et al. (1998) High High High Chikkalingaiah et al. (1999) Low Low Low Niranjana Murthy et al. (1999) Moderate High High Nagajyothi (2001) Low - - Tara Satyavathi et al. (2001) - Moderate Moderate Venkata Suresh ( 2001)

50 Table 2.3 (Cont.) High High Nayak et al. (2002) High Chaudhary and Mothiramani (2003) High - - Sinha et al. (2004) - High High Suman et al. (2005) High moderate Patra et al. (2006) - High High Sankar et al. (2006) - Moderate Moderate Bharadwaj et al.(2007) low low High High High Nayudu et al. (2007) Moderate - - Ashok kumar tuwar et al. (2013) - High High Krishna et al. (2008) High Moderate High Anbanandan et al. (2009) high High Low Akinwale et al. (2011) Low High High Manoj kumar et al. (2011) Moderate Low High Sangam Kumar Singh et al. (2011) Low High High Venkata Subbaiah et al. (2011) High High High Ravindrababu et al. (2012) Moderate High High Pawan saini et al. (2013) Moderate Moderate Moderate Rajesh Kumar Dhanwani et al. (2013) High High High Vanisree et al. (2013) Panicle length F 2 - High - Sardhana and Borthakur (1987) F 2 Low Low Lowmoderate Marimuthu et al.(1990) - - Moderate Reddy and Nerkar (1991) - High Moderate Remabai et al. (1992) low High Moderate Chaubey and Singh (1994) low High Low Chookar et al. (1994) F 2 Low Moderate Moderate Ganesan and Subramaniam (1994) Low - - Rao and Shrivastav (1994) Low Moderate Low Chauhan (1996) F 2 Low Moderate Low Ganeshan et al.(1996) Low Moderate low Reddy and De (1996) Low - - Manonmani et al. (1996) - Low Low Singh and Chaudhary (1996) F 4 low High Moderate Nath and Talukdar (1997) Low - - Vange and Ojo (1997) - High Moderate Borbora and Hazarika (1998) - High Moderate Mokate et al.(1998) Low High High Chikkalingaiah et al. (1999) - High - Kaw et al. (1999) High - - Tripathi et al. (1999) Low High Moderate Nagajyothi (2001) Low - - Tara Satyavathi et al. (2001) - High Moderate Venkata Suresh ( 2001) Moderate High High Nayak et al. (2002) Low Patil et al. (2003) - High Moderate Suman et al. (2005) - High Moderate Patra et al. (2006) High High High Nayudu et al. (2007) Low Krishna et al. (2008) High High High Ashok kumar tuwar et al. (2013) Low High low Akinwale et al. (2011) Low High Moderate Manoj kumar et al. (2011) Low Moderate High Sangam Kumar Singh et al. (2011) Low High Low Venkata Subbaiah et al. (2011) Moderate High High Ravindrababu et al. (2012) Moderate High High Pawan saini et al. (2013) Low High Low Rajesh Kumar Dhanwani et al. (2013)

51 Table 2.3 (Cont.) High High High Vanisree et al. (2013) Panicle weight High High High Ashok kumar tuwar et al. (2013) Moderate High High Akinwale et al. (2011) Low High High Vanisree et al. (2013) Filled grains per panicle F 2 high High High Marimuthu et al.(1990) - High High Prasanthi (1993) High - - Sarma and Roy (1993) Moderate High High Chaubey and Singh (1994) High High High Chookar et al. (1994) F 2 High High High Ganeshan et al.(1996) F 2 High Moderate High Ganesan and Subramaniam (1994) F 2 - Moderate Moderate- Murthy (1994) high High High - - Rao and Srivastava (1994) High High High Govindarasu (1995) High Moderate Moderate Chauhan (1996) High High High Reddy and De (1996) P+F 1 +F 2 High Moderate Moderate Singh and Chowdhary (1996) F 4 Low Moderate Low Nath and Talukdar (1997) High High High Borbora and Hazarika (1998) High Debchoudhury and Das (1998) - High High Gupta et al. (1998) F 2 - High High Thakur et al. (1999) High High High Nagajyothi (2001) High - - Tara Satyavathi et al. (2001) High - - Madhavilatha (2002) High High High Nayak et al. (2002) High High Patil et al. (2003) High High High Suman et al. (2005) - High High Sankar et al. (2006) - High High Vaithiyalingan and Nadarajan (2006) High High High Nayudu et al. (2007) High High Chandra Kishor et al. (2008) High High High Ashok kumar tuwar et al. (2013) High High High Krishna et al. (2008) High High High Akinwale et al. (2011) High High High Manoj kumar et al. (2011) Low High High Sangam Kumar Singh et al. (2011) High High High Venkata Subbaiah et al. (2011) Moderate High High Ravindrababu et al. (2012) High High High Pawan saini et al. (2013) High High High Rajesh Kumar Dhanwani et al. (2013) High High High Vanisree et al. (2013) Sardhana and Borthakur (1987) moderate - Moderate Moderate Ramesh Kumar (1989) high F 2 - High(ns) High Marimuthu et al.(1990) Low High Moderate Chaubey and Singh (1994) F 2 Low moderate Moderate Ganesan and Subramaniam (1994) F 2 - High High Murthy (1994) moderate moderate High High High Govindarasu (1995) F 2 Low High Moderate Chauhan (1996) F 2 Low- High Moderate Ganeshan et al.(1996) moderate high High - - Manonmani et al. (1996) Test weight F 2 Low High Low

52 Table 2.3 (Cont.) Moderate High Moderate Reddy and De (1996) High High - Singh and Chaudhary (1996) F 4 High High high Nath and Talukdar (1997) Moderate Vange and Ojo (1997) Low - High High Borbora and Hazarika (1998) High - - Leena Kumari and Valarmathi (1998) High High High Mokate et al.(1998) Low High Low Chikkalingaiah et al. (1999) High Kaw et al. (1999) Grain yield per plant Moderate - Low - Satya Priya Lalitha and Sreedhar (1999) Low - - Vange et al. (1999) High Low Nagajyothi (2001) Low Tara Satyavathi et al. (2001) Moderate - High High Nayak et al. (2002) Low High - - Chaudhary and Mothiramani (2003) High - - Patil et al. (2003) High High Moderate Sinha et al. (2004) - High Moderate Hasib (2005) - High Low Suman et al. (2005) - High High Sankar et al. (2006) High High High Nayudu et al. (2007) - High Low Vaithiyalingan and Nadarajan (2006) - High High Bharadwaj et al.(2007) High Moderate Chandra Kishor et al. (2008) High High Karad and Pol (2008) - High High Anbanandan et al. (2009) Low Moderate High Ashok kumar tuwar et al. (2013) Moderate High Moderate Akinwale et al. (2011) Low Low Low Manoj kumar et al. (2011) Moderate High High Sangam Kumar Singh et al. (2011) Moderate High High Ravindrababu et al. (2012) Moderate High High Pawan saini et al. (2013) Low High Low Rajesh Kumar Dhanwani et al. (2013) High High High Vanisree et al. (2013) F 2 High High High Ganesan and Subramaniam (1994) F 2 - High- High Murthy (1994) moderate moderate High - - Rao and Srivatsav (1994) Low - - Supiryo Chakrabarthy and Hazarika (1994) High High High Chauhan (1996) F 2 High High High Ganeshan et al.(1996) High High High Reddy and De (1996) F 4 High High High Nath and Talukdar (1997) High High High Balan et al. (1999) High High High Niranjana Murthy et al. (1999) High Moderate Moderate Satya Priya Lalitha and Sreedhar (1999) F 2 - Low(ns) moderate Sreedhar (1999) Moderate High High Nagajyothi (2001) Moderate - - Tara Satyavathi et al. (2001) High High High Madhavilatha (2002) High High High Nayak et al. (2002) High - - Chaudhary and Mothiramani (2003)

53 Table 2.3 (Cont.) High High Patil et al. (2003) High High Moderate Sinha et al. (2004) High High High Suman et al. (2005) - High Moderate Patra et al. (2006) - High High Sankar et al. (2006) - Low Low Bharadwaj et al. (2007) moderate moderate High High High Nayudu et al. (2007) High - - Krishna et al. (2008) Moderate - High High Kumar et al. (2008) High High High High Anbanandan et al. (2009) High Moderate High Ashok kumar tuwar et al. (2013) High High Moderate Akinwale et al. (2011) Low High High Manoj kumar et al. (2011) Moderate High High Sangam Kumar Singh et al. (2011) Moderate High High Venkata Subbaiah et al. (2011) High High High Ravindrababu et al. (2012) High High High Pawan saini et al. (2013) Low Low Low Rajesh Kumar Dhanwani et al. (2013) High High High Vanisree et al. (2013) Quality characters Kernel length F 2 - High High Murthy (1994) moderate moderate F 2 Low High Moderate Chauhan (1996) high High - - Pathak and Sharma (1996) P+F 1 Low High moderate Vivekanandan and Giridharan (1998) - High Low Chikkalingaiah et al. (1999) High High Moderate Sarawgi et al. (2000) - High Low Venkata Suresh (2001) - High Low Madhavilatha (2002) Moderate - - Nayak et al. (2002) Low - High Low Surender Raju (2002) Moderate - - Chaudhary and Mothiramani (2003) Moderate High Low Nayak et al. (2003) - High Moderate Bharadwaj et al. (2007) Low High Moderate Krishna et al. (2008) Low Low Moderate Venkata Subbaiah et al. (2011) Low High Low Ravindrababu et al. (2012) Moderate High High Pawan saini et al. (2013) Low High Low Rajesh Kumar Dhanwani et al. (2013) High High High Vanisree et al. (2013) Kernel breadth F 2 - High High Murthy (1994) moderate moderate F 2 Low - High Moderate Chauhan (1996) moderate high High - - Pathak and Sharma (1996) Low - - Reddy and De (1996) P+F 1 Low high moderate Vivekanandan and Giridharan (1998) Low Low Low Chikkalingaiah et al. (1999) High Moderate Sarawgi et al. (2000) Moderate - Low High Low Surender Raju (2002)

54 Table 2.3 (Cont.) High Low Venkata Suresh (2001) - High Low Madhavilatha (2002) - High High Nayak et al. (2002) Low Krishna et al. (2008) Low Low Low Venkata Subbaiah et al. (2011) Low High Low Ravindrababu et al. (2012) Low High Moderate Pawan saini et al. (2013) Low High Low Rajesh Kumar Dhanwani et al. (2013) High High High Vanisree et al. (2013) Kernel L/B - High Low Deosarkar et al. (1989) ratio Low - - Ramesh kumar (1989) F 2 - High High Murthy (1994) moderate moderate F 2 Low High Medium Chauhan (1996) High - - Pathak and Sharma (1996) F 3 Moderate Low Sahdev Singh et al. (1996) P+F 1 Moderate High High Vivekanandan and Giridharan (1998) Low Moderate Low Chikkalingaiah et al. (1999) Moderate High Moderate Satya Priya Lalitha and Sreedhar (1999) High High High Sarawgi et al. (2000)_ Moderate High High Nagajyothi (2001) Moderate High Low Sakthivel (2001) Low - - Tara Satyavathi et al. (2001) - High Low Venkata Suresh (2001) Moderate High High Nayak et al. (2002) High High Low Madhavilatha (2002) Moderate - - Chaudhary and Mothiramani (2003) Moderate High High Nayak et al. (2003) - High Low Madhavilatha (2005) - High High Bharadwaj et al. (2007) Low High Moderate Krishna et al. (2008) Low Low Moderate Venkata Subbaiah et al. (2011) Low High Low Ravindrababu et al. (2012) Moderate High High Rajesh Kumar Dhanwani et al. (2013) moderate High Low Vanisree et al. (2013) Kernel length Low Low Low Venkata Subbaiah et al. (2011) after cooking Kernel elongation ratio Head recovery rice Moderate High High Rajesh Kumar Dhanwani et al. (2013) Low Low Low Venkata Subbaiah et al. (2011) Low High Moderate Rajesh Kumar Dhanwani et al. (2013) Moderate High High Ravindrababu et al. (2012) Low High Moderate Rajesh Kumar Dhanwani et al. (2013) Low Low Low Vanisree et al. (2013)

55 2.5 CHARACTER ASSOCIATION Study of character associations helps the breeder in fixing selection criteria for grain yield in parental lines, such that selections will be effective in isolating the plants with desired combination of characters. Phenotypic correlation is the correlation of phenotypic values and is subjected to changes in the environment. It measures the environment deviation together with non-additive gene action. Genotypic correlation is the correlation of breeding value (Additive + Additive x Additive epistatic) gene action. Hence, knowledge of association between different characters is highly essential for planning a sound breeding programme. Several workers have studied the correlation coefficients in rice and contradictory association have been reported for almost all the character pairs which may be due to the different experimental material handled by them. A brief review of studies on the association of characters in rice is presented hereunder in Table 2.4: Table 2.4. Review of literature on association of yield component characters with grain yield per plant in rice Character Nature of association Reference Days to 50% flowering Positive significant Selvarani and Rangaswamy (1998) Balan et al. (1999) Sakthivel (2001) Madhavilatha (2002) Mahto et al. (2003) Suman (2003) Kuldeep et al. (2004) Vinothini and Ananda Kumar (2005) Krishna et al. (2008) Akhtar et al. (2011) Gopikannan and Ganesh (2013) Rajendar Reddy et al. (2014) Positive non-significant Kumar et al.(1998) Rao and Shrivastav (1999) Vange et al. (1999) Krishna Naik et al. (2005) Madhavi Latha et al. (2005) Swain and Reddy (2006) Sharma and Sharma (2007) Satish Chandra et al. (2009)

56 Table 2.4 (Cont.) Character Nature of association Reference Negative non-significant Meenakshi et al. (1999) Chitra et al. (2005) Malini et al. (2007) Panwar and Mashiat Ali (2007) Negative significant Borbora et al. (2005) Eradasappa et al. (2007) Anbumalarmathi and Nadarajan (2008) Plant height Positive significant Debchoudhury and Das (1998) Bala (2001) Nayak et al. (2001) Sakthivel (2001) Madhavilatha (2002) Vinothini and Ananda Kumar (2005) Eradasappa et al. (2007) Malini et al. (2007) Krishna et al. (2008) Immanuel Selvaraj et al. (2011) Gopikannan and Ganesh (2013) Rafii et al. (2014) Rajendar Reddy et al. (2014) Positive non-significant Chitra et al. (2005) Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Manna et al. (2006) Swain and Reddy (2006) Sharma and Sharma (2007) Yugandhar Reddy et al. (2008) Negative non-significant Gupta et al. (1998) Meenakshi et al. (1999) Krishna Veni and Shobha Rani (2006) Negative significant Rao and Shrivastav (1999) Tara Satyavathi et al. (2001) Mahto et al. (2003) Borbora et al. (2005) Panwar and Mashiat Ali (2007) Anbumalarmathi and Nadarajan (2008) Panicle length Positive significant Bala (2001) Nayak et al. (2001) Sakthivel (2001) Madhavilatha (2002) Suman (2003) Kuldeep et al. (2004) Krishna Veni and Shobha Rani (2005) Vinothini and Ananda Kumar (2005) Eradasappa et al. (2007) Malini et al. (2007) Sharma and Sharma (2007) Yugandhar Reddy et al. (2008) Satish Chandra et al. (2009)

57 Table 2.4 (Cont.) Character Nature of association Reference Aktar et al (2011) Basavaraja et al. (2011) Eidi Kohnaki et al. (2013) Immanuel Selvaraj et al. (2011) Shanthi et al. (2011) Rajendar Reddy et al. (2014) Sudharani et al. (2014) No. of productive tillers per plant Positive, non-significant Vange et al. (1999) Tara Satyavathi et al. (2001) Borbora et al. (2005) Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2006) Manna et al. (2006) Krishna et al. (2008) Negative, non-significant Ramesh Babu (1999) Chitra et al. (2005) Panwar and Mashiat Ali (2007) Positive, significant Nayak et al. (2001) Tara Satyavathi et al. (2001) Madhavilatha (2002) Suman (2003) Kuldeep et al. (2004) Chitra et al. (2005) Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Vinothini and Ananda Kumar (2005) Manna et al. (2006) Swain and Reddy (2006) Krishna Veni and Shobha Rani (2006) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Anbumalarmathi and Nadarajan (2008) Krishna et al. (2008) Satish Chandra et al. (2009) Eidi Kohnaki et al. (2013) Immanuel Selvaraj et al. (2011) Ravinder babu et al. (2012) Gopikannan and Ganesh (2013) Positive, non-significant Reddy et al. (1997) Madhavi Latha et al. (2005) Sharma and Sharma (2007) Negative, non-significant Awasthi and Borthakur (1986) Haque et al. (1991) Panicle weight Positive significant Padmavathi et al. (1996) Meenakshi et al. (1999) Nayak et al. (2001) Madhavilatha (2002) Satish et al. (2003) Khedikar et al. (2004) Sarkar et al.(2005) Senapati et al.(2009) Ravindra Babu et al. (2012)

58 Table 2.4 (Cont.) Character Nature of association Reference Number of filled grains per panicle 1000-grain weight Positive significant Madhavilatha (2002) Krishna Veni and Shobha Rani (2005) Vinothini and Ananda Kumar (2005) Malini et al. (2007) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Sharma and Sharma (2007) Anbumalarmathi and Nadarajan (2008) Krishna et al. (2008) Satish Chandra et al. (2009) Akhtar et al. (2011) Eidi Kohnaki et al. (2013) Immanuel Selvaraj et al. (2011) Gulzar et al. (2012) Gopikannan and Ganesh (2013) Sudharani et al. (2014) Positive Non-significant Borbora et al. (2005) Madhavi Latha et al. (2005) Krishna Veni and Shobha Rani (2006) Swain and Reddy (2006) Negative Non-significant Krishna Naik et al. (2005) Ravinder babu et al. (2012) Positive significant Madhavilatha (2002) Tara Satyavathi et al. (2002) Sinha et al. (2004) Kuldeep et al. (2004) Borbora et al. (2005) Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Krishna Veni and Shobha Rani (2006) Anbumalarmathi and Nadarajan (2008) Satish Chandra et al. (2009) Akhtar et al. (2011) Immanuel Selvaraj et al. (2011) Gopikannan and Ganesh (2013) Positive Non-significant Negative Non-significant Rajendar Reddy et al. (2014) Gupta et al. (1998) Vange et al. (1999) Chitra et al. (2005) Madhavi Latha et al. (2005) Eradasappa et al. (2007) Sharma and Sharma (2007) Yugandhar Reddy et al. (2008) Swain and Reddy (2006) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Ravinder babu et al. (2012) Negative Significant Suman (2003) Kernel length Positive and significant Sadhukhan et al. (2000) Rajendar Reddy et al. (2014) Positive and non-significant Reddy et al. (1997) Madhavi Latha (2002)

59 Table 2.4 (Cont.) Character Nature of association Reference Negative and significant Nayak et al. (2001) Krishna Veni and Shobha Rani (2006) Krishna et al. (2008) Gopikannan and Ganesh (2013) Negative and non-significant Asha Christopher et al. (1999) Kernel breadth Positive significant De et al. (2005) Krishna Veni and Shobha Rani (2006) Rafii et al. (2014) Rajendar Reddy et al. (2014) Positive non-significant Reddy et al. (1997) Madhavi Latha (2002) Negative non-significant Asha Christopher et al. (1999) Krishna et al. (2008) Kernel L/B ratio Positive significant Tara Satyavathi et al. (2001) Positive non-significant Ramesh Babu (1999) Madhavi Latha (2002) Negative non-significant Sharma and Sharma (2007) Negative significant Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2006) Krishna et al. (2008) Association among the yield component traits in rice: association of days to 50 per cent flowering with Character Nature of association Reference Plant height Positive significant Kavitha and Sree Rama Reddi (2001) Sakthivel (2001) Madhavilatha (2002) Borbora et al. (2005) Krishna Naik et al. (2005) Panwar and Mashiat Ali (2007) Anbumalarmathi and Nadarajan (2008) Ravinder babu et al. (2012) Positive Non-significant Malini et al. (2007) Sharma and Sharma (2007) Krishna et al. (2008) Negative significant Satish Chandra et al. (2009) Jayasudha and Sharma (2010) Immanuel Selvaraj et al. (2011) Negative Non-significant Swain and Reddy (2006) Eradasappa et al. (2007) Panicle length Positive significant Nayak et al. (2001) Sakthivel (2001) Madhavilatha (2002) Suman (2003) Sharma and Sharma (2007) Ravinder babu et al. (2012) Rajendar Reddy et al. (2014) Positive Non-significant Kavitha and Sree Rama Reddi (2001) Borbora et al. (2005) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Negative Non-significant Ramesh Babu (1999) Chitra et al. (2005) Malini et al. (2007)

60 Table (Cont.) Character Nature of association Reference Negative Significant Eradasappa et al. (2007) Venkanna et al. (2014) Number of production tillers per plant Number of filled grains per panicle Positive significant Sakthivel (2001) Chitra et al. (2005) Positive Non-significant Kavitha and Sree Rama Reddi (2001) Surender Raju (2002) Swain and Reddy (2006) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Satish Chandra et al. (2009) Negative Non-significant Chitra et al. (2005) Sharma and Sharma (2007) Negative significant Krishna Naik et al. (2005) Eradasappa et al. (2007) Anbumalarmathi and Nadarajan (2008) Jayasudha and Sharma (2010) Immanuel Selvaraj et al. (2011) Ravinder babu et al. (2012) Positive significant Kavitha and Sree Rama Reddi (2001) Nayak et al. (2001) Madhavilatha (2002) Krishna Naik et al. (2005) Ravinder babu et al. (2012) Venkanna et al. (2014) Positive Non-significant Vange et al. (1999) Borbora et al. (2005) Chitra et al. (2005) Swain and Reddy (2006) Malini et al. (2007) Sharma and Sharma (2007) Krishna et al. (2008) Negative Non-significant Meenakshi et al. (1999) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Negative Significant Anbumalarmathi and Nadarajan (2008) 1000-grain weight Positive significant Krishna Naik et al. (2005) Sharma and Sharma (2007) Positive and nonsignificant Roy et al. (1995) Borbora et al. (2005) Panwar and Mashiat Ali (2007) Negative non-significant Chitra et al. (2005) Swain and Reddy (2006) Eradasappa et al. (2007) Satish Chandra et al. (2009) Negative significant Ramesh Babu (1999) Kavitha and Sree Rama Reddi (2001) Nayak et al. (2001) Sakthivel (2001) Krishna Veni and Shobha Rani (2006) Anbumalarmathi and Nadarajan (2008) Krishna et al. (2008) Ravinder babu et al. (2012) Gopikannan and Ganesh (2013) Venkanna et al. (2014)

61 Table (Cont.) Character Nature of association Reference Kernel length Negative significant Krishna et al. (2008) Gopikannan and Ganesh (2013) Venkanna et al. (2014) Kernel breadth Negative significant Krishna et al. (2008) Gopikannan and Ganesh (2013) Kernel L/B ratio Positive significant Ravinder babu et al. (2012) Gopikannan and Ganesh (2013) Positive non-significant Sharma and Sharma (2007) Venkanna et al. (2014) Negative non-significant Krishna Veni and Shobha Rani (2006) Krishna et al. (2008) Satish Chandra et al. (2009) Negative significant Krishna Naik et al. (2005) Association among the yield component traits in rice: association of plant height with Character Nature of association Reference Panicle length Positive significant Tara Satyavathi et al. (2001) Madhavilatha (2002) Suman (2003) Sinha et al. (2004) Chitra et al. (2005) Krishna Naik et al. (2005) Krishna et al. (2008) Ravinder babu et al. (2012) Gopikannan and Ganesh (2013) Rajender Reddy et al. (2014) Venkanna et al. (2014) Positive non-significant Borbora et al. (2005) Krishna Veni and Shobha Rani (2005) Manna et al. (2006) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Yugandhar Reddy et al. (2008) Negative significant Ananda Kumar (1992) Negative non significant Krishna Veni and Shobha Rani (2006) Negative significant Ananda Kumar (1992) Number of productive tillers per plant Positive significant Kavitha and Sree Rama Reddi (2001) Sakthivel (2001) Surender Raju (2002) Krishna et al. (2008) Satish Chandra et al. (2009) Gopikannan and Ganesh (2013) Rajender Reddy et al. (2014) Positive Non-significant Chitra et al. (2005) Krishna Naik et al. (2005) Swain and Reddy (2006) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Sharma and Sharma (2007)

62 Table (Cont.) Character Nature of association Reference Negative Non significant Krishna Veni and Shobha Rani (2005) Manna et al. (2006) Negative significant Meenakshi et al. (1999) Nayak et al. (2001) Anbumalarmathi and Nadarajan (2008) Yugandhar Reddy et al. (2008) Akhtar et al. (2011) Ravinder babu et al. (2012) Venkanna et al. (2014) Number of filled grains per panicle Positive significant Nayak et al. (2001) Madhavilatha (2002) Krishna Naik et al. (2005) Satish Chandra et al. (2009) Ravinder babu et al. (2012) Gopikannan and Ganesh (2013) Positive non-significant Kavitha and Sree Rama Reddi (2001) Chitra et al. (2005) Krishna Veni and Shobha Rani (2005) Manna et al. (2006) Krishna Veni and Shobha Rani (2006) Eradasappa et al. (2007) Malini et al. (2007) Sharma and Sharma (2007) Satish Chandra et al. (2009) Negative non-significant Swain and Reddy (2006) Krishna et al. (2008) Negative significant Debchoudhury and Das (1998) Surender Raju (2002) Panwar and Mashiat Ali (2007) Anbumalarmathi and Nadarajan (2008) Akhtar et al. (2011) Panicle weight Positive and significant Sudharani et al. (2014) Negative significant Venkanna et al. (2014) 1000-grain weight Positive and significant Yogameenakshi et al. (2004) Krishna Naik et al. (2005) Panwar and Mashiat Ali (2007) Table (Cont.) Character Nature of association Reference Krishna et al. (2008) Ravinder babu et al. (2012) Gopikannan and Ganesh (2013) Venkanna et al. (2014) Positive and nonsignificant Ramesh Babu (1999) Borbora et al. (2005) Krishna Veni and Shobha Rani (2005) Eradasappa et al. (2007) Sharma and Sharma (2007) Yugandhar Reddy et al. (2008) Negative non-significant Meenakshi et al. (1999) Nayak et al. (2001) Chitra et al. (2005) Swain and Reddy (2006) Negative significant Krishna Veni and Shobha Rani (2006) Anbumalarmathi and Nadarajan (2008)

63 Table (Cont.) Character Nature of association Reference Kernel length Positive significant Krishna et al. (2008) Ravinder babu et al. (2012) Gopikannan and Ganesh (2013) Venkanna et al. (2014) Positive and nonsignificant Krishna Veni and Shobha Rani (2006) Kernel breadth Positive significant Krishna et al. (2008) Ravinder babu et al. (2012) Venkanna et al. (2014) Negative non-significant Krishna Veni and Shobha Rani (2006) Kernel L/B ratio Positive and nonsignificant Sharma and Sharma (2007) Krishna et al. (2008) Negative significant Venkanna et al. (2014) Negative non-significant Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2006) Association among the yield component traits in rice: association of panicle length with Character Nature of association Reference Number of productive tillers per plant Number of filled grains per panicle Positive significant Janardhanam et al. (2001) Sakthivel (2001) Eradasappa et al. (2007) Rajendar Reddy et al. (2014) Positive Non significant Kavitha and Sree Rama Reddi (2001) Chitra et al. (2005) Krishna Veni and Shobha Rani (2005) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Yugandhar Reddy et al. (2008) Negative non-significant Sharma and Sharma (2007) Negative significant Tara Satyavathi et al. (2001) Suman (2003) Krishna Naik et al. (2005) Manna et al. (2006) Ravinder babu et al. (2012) Positive significant Janardhanam et al. (2001) Kavitha and Sree Rama Reddy (2001) Yogameenakshi et al. (2004) Krishna Veni and Shobha Rani (2005) Eradasappa et al. (2007) Satish Chandra et al. (2009) Ravinder babu et al. (2012) Sudharani et al. (2014) Positive non-significant Tara Satyavathi et al. (2001) Borbora et al. (2005) Chitra et al. (2005) Krishna Naik et al. (2005) Malini et al. (2007) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Negative non-significant Krishna Veni and Shobha Rani (2006) Sharma and Sharma (2007)

64 Table (Cont.) Character Nature of association Reference Negative significant Manna et al. (2006) 1000-grain weight Positive significant Krishna Veni and Shobha Rani (2005) Krishna Veni and Shobha Rani (2006) Sharma and Sharma (2007) Krishna et al. (2008) Ravinder babu et al. (2012) Gopikannan and Ganesh (2013) Rajender Reddy et al. (2014) Sudharani et al. (2014) Venkanna et al. (2014) Positive non-significant Kavitha and Sree Rama Reddi (2001) Borbora et al. (2005) Yugandhar Reddy et al. (2008) Negative non-significant Nayak et al. (2001) Chitra et al. (2005) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Negative significant Sukanya Subramanian and Rathinam (1984) Panicle weight Positive significant Sudharani et al. (2014) Kernel length Positive significant Krishna et al. (2008) Rajender Reddy et al. (2014) Venkanna et al. (2014) Negative Non-significant Krishna Veni and Shobha Rani (2006) Kernel breadth Positive significant Krishna et al. (2008) Ravinder babu et al. (2012) Sudharani et al. (2014) Venkanna et al. (2014) Positive Non-significant Krishna Veni and Shobha Rani (2006) Kernel L/B ratio Krishna et al. (2008) Positive significant Gopikannan and Ganesh (2013) Rajender Reddy et al. (2014) Negative Non-significant Sharma and Sharma (2007) Negative Significant Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2006) Association among the yield component traits in rice: association of number of productive tillers per plant with Character Nature of association Reference Plant height Positive significant Sakthivel (2001) Panicle length Positive significant Roy et al. (1995) Sakthivel (2001) Eradasappa et al., (2007) Negative significant Tara Satyavathi et al. (2001) Suman (2003) Krishna Naik et al., (2005) Manna et al. (2006) Number of filled grains per panicle Positive significant Meenakshi et al. (1999) Janardhanam et al. (2001) Eradasappa et al. (2007) Anbumalarmathi and Nadarajan (2008)

65 Table (Cont.) Character Nature of association Reference Gopikannan and Ganesh (2013) Sudharani et al. (2014) Venkanna et al. (2014) Positive non-significant Chitra et al. (2005) Krishna Veni and Shobha Rani (2005) Swain and Reddy (2006) Negative non-significant Kavitha and Sree Rama Reddy (2001) Nayak et al. (2001) Manna et al. (2006) Panwar and Mashiat Ali (2007) Sharma and Sharma (2007) Krishna et al. (2008) Satish Chandra et al. (2009) Negative significant Tara Satyavathi et al. (2001) Krishna Naik et al. (2005) Venkanna et al. (2014) 1000-grain weight Positive significant Suryanarayana (2000) Sakthivel (2001) Anbumalarmathi and Nadarajan (2008) Gopikannan and Ganesh (2013) Positive non-significant Meenakshi et al. (1999) Kavitha and Sree Rama Reddy (2001) Tara Satyavathi et al. (2001) Chitra et al. (2005) Krishna Veni and Shobha Rani (2005) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Negative non-significant Krishna Naik et al. (2005) Sharma and Sharma (2007) Yugandhar Reddy et al. (2008) Negative significant Nayak et al. (2001) Swain and Reddy (2006) Eradasappa et al. (2007) Ravinder babu et al. (2012) Kernel length Positive non-significant Krishna et al. (2008) Kernel breadth Positive significant Krishna et al. (2008) Kernel L/B ratio Positive significant Sharma and Sharma (2007) Positive non-significant Krishna Naik et al. (2005) Negative non-significant Krishna et al. (2008) Association among the yield component traits in rice: association of number of filled grains per panicle with Character Nature of association Reference 1000-grain weight Positive significant Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Anbumalarmathi and Nadarajan (2008) Gopikannan and Ganesh (2013) Sudharani et al. (2014) Positive non-significant Meenakshi et al. (1999) Chitra et al. (2005) Krishna Veni and Shobha Rani (2006)

66 Table (Cont.) Character Nature of association Reference Negative non-significant Vange et al. (1999) Kavitha and Sree Rama Reddi (2001) Eradasappa et al. (2007) Negative significant Nayak et al. (2001) Borbora et al. (2005) Swain and Reddy (2006) Panwar and Mashiat Ali (2007) Sharma and Sharma (2007) Krishna et al. (2008) Venkanna et al. (2014) Kernel length Negative significant Krishna Veni and Shobha Rani (2006) Krishna et al. (2008) Kernel breadth Positive and non-significant Krishna Veni and Shobha Rani (2006) Negative significant Krishna et al. (2008) Gopikannan and Ganesh (2013) Venkanna et al. (2014) Kernel L/B ratio Negative significant Krishna et al. (2008) Venkanna et al. (2014) Negative non-significant Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2006) Sharma and Sharma (2007) Positive and significant Gopikannan and Ganesh (2013) Association among the yield component traits in rice: association of Panicle weight with Character Nature of association Reference Filled Positive, significant Sudharani et al. (2014) grains/panicle 1000 grain weight Positive, significant Sudharani et al. (2014) Association among the yield component traits in rice: association of 1000 grain weight with Character Nature of association Reference Kernel length Positive significant Krishna et al. (2008) Gopikannan and Ganesh (2013) Venkanna et al. (2014) Negative significant Krishna Veni and Shobha Rani (2006) Kernel breadth Positive significant Krishna Veni and Shobha Rani (2006) Krishna et al. (2008) Kernel L/B ratio Positive significant Krishna et al. (2008) Venkanna et al. (2014) Negative non-significant Krishna Veni and Shobha Rani (2006) Sharma and Sharma (2007) Negative significant Krishna Naik et al. (2005)

67 2.4.8 Association among the yield component traits in rice: association of kernel length with Character Nature of association Reference Kernel breadth Positive significant Krishna et al. (2008) Rafii et al. (2014) Rajendar Reddy et al. (2014) Venkanna et al. (2014) Negative significant Krishna Veni and Shobha Rani (2006) Kernel L/B ratio Positive significant Krishna Veni and Shobha Rani (2006) Nayak et al. (2001) Madhavi Latha (2002) Nayak et al. (2003) Krishna et al. (2008) Gopikannan and Ganesh (2013) Venkanna et al. (2014) 1000-grain weight(g) Positive significant Singh et al. (1998) Nayak et al. (2001) Madhavi Latha (2002) Positive non-significant De and Suriya Rao (1988) Negative non-significant Madhavi Latha (2002) Association among the yield component traits in rice: association of Kernel breadth with Character Nature of association Reference Kernel L/B ratio Negative non-significant Krishna Veni and Shobha Rani (2006) Negative and Significant Gopikannan and Ganesh (2013) Venkanna et al. (2014) Association among the yield component traits in rice: association of kernel L/B ratio with Character Nature of association Reference 1000-grain weight(g) Positive significant Nayak et al. (2001) Tara Satyavathi et al. (2001) Positive non-significant Ramesh Babu (1999) Kavitha and Sree Rama Reddi (2001) Negative significant Sarwar et al. (1999)

68 2.6 PATH COEFFICIENT ANALYSIS Path coefficient analysis, a statistical device developed by Wright (1921) helps in partitioning of the correlation coefficients into direct and indirect effects of independent variable on dependent variable. As grain yield is a complex character influenced by several factors, selection based on simple correlation without taking into consideration between the component characters is not effective. Hence, path analysis is of much importance in any plant breeding programme. Correlation in combination with path analysis would give a better insight into cause and effect relationship between different pairs of characters. Dewey and Lu (1959) and Frakes et al. (1961) demonstrated the utility of path coefficient analysis in plant selection and since then its application has been extended to almost every crop. The findings of earlier workers on the relative contribution of different characters to grain yield in rice are furnished hereunder in a tabular form (Table 5): 2.5 Review of literature on direct and indirect effects of yield contributing traits on grain yield in rice Direct effects Character Positive indirect effect Negative indirect effect Days to 50 per cent flowering Selvarani and Rangaswamy (1998) Balan et al. (1999) Bala (2001) Madhavilatha (2002) Suman (2003) Khedikar et al. (2004) Chitra et al. (2005) Krishna Naik et al. (2005) Manonmani and Ranganathan (2006) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Satish Chandra et al. (2009) Akhtar et al. (2011) Selvaraj et al. (2011) Kumar and Senapathi (2013) Debchoudhury and Das (1998) Gupta et al. (1998) Kavitha and Sree Rama Reddi (2001) Nayak et al. (2001) Borbora et al. (2005) Vinothini and Ananda Kumar (2005) Swain and Reddy (2006) Eradasappa et al. (2007) Anbumalarmathi and Nadarajan (2008) Yadav et al. (2010) Ravindra Babu et al. (2012) Imad Naseem et al. (2014) Tirumala Rao et al. (2014) Plant height Chitra et al. (2005) Krishna Veni and Shobha Rani (2005) Manna et al. (2006) Manonmani and Ranganathan (2006) Swain and Reddy (2006) Eradasappa et al. (2007) Krishna et al. (2008) Chakraborty et al. (2010) Selvaraj et al. (2011) Venkanna et al. (2014) Gupta et al. (1998) Tara Satyavathi et al. (2001) Suman (2003) Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Panwar and Mashiat Ali (2007) Anbumalarmathi and Nadarajan (2008) Satish Chandra et al. (2009) Akhtar et al. (2011) Ravindra Babu et al. (2012)

69 Table (Cont.) Character Positive indirect effect Negative indirect effect Kumar and Senapathi (2013) Imad Naseem et al. (2011) Tirumala Rao et al. (2014) Panicle length Kavitha and Sree Rama Reddi (2001) Nagajyothi (2001) Suman (2003) Khedikar et al. (2004) Chitra et al. (2005) Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Vinothini and Ananda Kumar (2005) Manna et al. (2006) Malini et al. (2007) Panwar and Mashiat Ali (2007) Yadav et al. (2010) Chakraborty et al. (2010) Selvaraj et al. (2011) Ravindra Babu et al. (2012) Kumar and Senapathi (2013) Tirumala Rao et al. (2014) Nayak et al. (2001) Madhavilatha (2002) Borbora et al. (2005) Manonmani and Ranganathan (2006) Eradasappa et al. (2007) Krishna et al. (2008) Satish Chandra et al. (2009) Imad Naseem et al. (2014) Number of productive tillers per plant Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Vinothini and Ananda Kumar (2005) Manna et al. (2006) Manonmani and Ranganathan (2006) Swain and Reddy (2006) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Anbumalarmathi and Nadarajan (2008) Krishna et al. (2008) Satish Chandra et al. (2009) Chakraborty et al. (2010) Ravindra Babu et al. (2012) Kumar and Senapathi (2013) Imad Naseem et al. (2014) Tirumala Rao et al. (2014) Valarmathi and Leenakumari (1998) Kavitha and Sree Rama Reddi (2001) Chitra et al. (2005) Yadav et al. (2010) Akhtar et al. (2011) Selvaraj et al. (2011) Panicle weight Kumar and Senapati (2013) Sarker et al. (2013) Number of filled Janardhanam et al. (2001) grains per Nayak et al. (2001) panicle Madhavilatha (2002) Satish et al. (2003) Yogameenakshi et al. (2004) Borbora et al. (2005) Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Manonmani and Ranganathan (2006) Swain and Reddy (2006) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Malini et al. (2007) Venkanna et al. (2014) Gupta et al. (1998) Chitra et al. (2005) Vinothini and Ananda Kumar (2005) Manna et al. (2006) Anbumalarmathi and Nadarajan (2008) Chakraborty et al. (2010) Akhtar et al. (2011) Ravindra Babu et al. (2012) Kumar and Senapathi (2013)

70 Table (Cont.) Character Positive indirect effect Negative indirect effect Krishna et al. (2008) Yugandhar Reddy et al. (2008) Satish Chandra et al. (2009) Yadav et al. (2010) Selvaraj et al. (2011) Imad Naseem et al. (2014) Tirumala Rao et al. (2014) Venkanna et al. (2014) 1000-grain weight Sinha et al. (1999) Nayak et al. (2001) Tara Satyavathi et al. (2001) Madhavilatha (2002) Suman (2003) Khedikar et al. (2004) Yogameenakshi et al. (2004) Chitra et al. (2005) Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Vinothini and Ananda Kumar (2005) Manonmani and Ranganathan (2006) Swain and Reddy (2006) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Anbumalarmathi and Nadarajan (2008) Krishna et al. (2008) Yugandhar Reddy et al. (2008) Satish Chandra et al. (2009) Yadav et al. (2010) Chakraborty et al. (2010) Akhtar et al. (2011) Selvaraj et al. (2011) Tirumala Rao et al. (2014) Gupta et al. (1998) Selvarani and Rangaswamy (1998) Kavitha and Sree Rama Reddi (2001) Borbora et al. (2005) Ravindra Babu et al. (2012) Kumar and Senapathi (2013) Imad Naseem et al. (2014) Venkanna et al. (2014) Kernel length Kumar and Senapathi (2013) Krishna et al. (2008) Venkanna et al. (2014) Kernel breadth Krishna et al. (2008) Kumar and Senapathi (2013) Venkanna et al. (2014) Kernel L/B ratio Krishna et al. (2008) Vinothini and Ananda Kumar (2005) Krishna Naik et al. (2005) Kumar and Senapathi (2013) Venkanna et al. (2014) Indirect effects Indirect effects of days to 50 per cent flowering on grain yield through Character Positive indirect effect Negative indirect effect Plant height Nayak et al. (2001) Madhavilatha (2002) Manonmani and Ranganathan (2006) Malini et al. (2007) Krishna et al. (2008) Selvaraj et al. (2011) Venkanna et al. (2014) Tirumala Rao et al. (2014) Debchoudhury and Das (1998) Borbora et al. (2005) Chitra et al. (2005) Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Swain and Reddy (2006) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007)

71 Table (Cont.) Character Positive indirect effect Negative indirect effect Anbumalarmathi and Nadarajan (2008) Yadav et al. (2010) Akhtar et al. (2011) Ravindra Babu et al. (2012) Kumar and Senapathi (2013) Imad Naseem et al. (2014) Panicle length Gupta et al. (1998) Kavitha and Sree Rama Reddi (2001) Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Yadav et al. (2010) Selvaraj et al. (2011) Ravindra Babu et al. (2012) Tirumala Rao et al. (2014) Number of productive tillers per plant Gupta et al. (1998) Madhavilatha (2002) Chitra et al. (2005) Manonmani and Ranganathan (2006) Swain and Reddy (2006) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Satish Chandra et al. (2009) Yadav et al. (2010) Akhtar et al. (2011) Kumar and Senapathi (2013) Panicle weight Swain and Reddy (2006) Kumar and Senapati (2013) Sarker et al. (2013) Number of filled grains per panicle 1000-grain weight Debchoudhury and Das (1998) Nayak et al. (2001) Madhavilatha (2002) Krishna Naik et al. (2005) Manonmani and Ranganathan (2006) Swain and Reddy (2006) Malini et al. (2007) Panwar and Mashiat Ali (2007) Anbumalarmathi and Nadarajan (2008) Krishna et al. (2008) Selvaraj et al. (2011) Kumar and Senapathi (2013) Imad Naseem et al. (2014) Kavitha and Sree Rama Reddi (2001) Madhavilatha (2002) Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Manonmani and Ranganathan (2006) Panwar and Mashiat Ali (2007) Yadav et al. (2010) Kumar and Senapathi (2013) Imad Naseem et al. (2014) Tirumala Rao et al. (2014) Sinha et al. (1999) Nayak et al. (2001) Madhavilatha (2002) Chitra et al. (2005) Manonmani and Ranganathan (2006) Malini et al. (2007) Satish Chandra et al. (2009) Kumar and Senapathi (2013) Imad Naseem et al. (2014) Meenakshi et al. (1999) Kavitha and Sree Rama Reddi (2001) Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Eradasappa et al. (2007) Anbumalarmathi and Nadarajan (2008) Selvaraj et al. (2011) Ravindra Babu et al. (2012) Tirumala Rao et al. (2014) Imad Naseem et al. (2014) Venkanna et al. (2014) Gupta et al. (1998) Meenakshi et al. (1999) Borbora et al. (2005) Chitra et al. (2005) Vinothini and Ananda Kumar (2005) Eradasappa et al. (2007) Satish Chandra et al. (2009) Yadav et al. (2010) Akhtar et al. (2011) Ravindra Babu et al. (2012) Tirumala Rao et al. (2014) Meenakshi et al. (1999) Nayak et al.(2001) Borbora et al. (2005) Chitra et al. (2005) Swain and Reddy (2006) Eradasappa et al. (2007) Anbumalarmathi and Nadarajan (2008) Krishna et al. (2008) Satish Chandra et al. (2009) Akhtar et al. (2011)

72 Table (Cont.) Character Positive indirect effect Negative indirect effect Selvaraj et al. (2011) Ravindra Babu et al. (2012) Kernel length Krishna et al. (2008) Kumar and Senapathi (2013) Kernel breadth Kumar and Senapathi (2013) Krishna et al. (2008) Kernel L/B Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Vinothini and Ananda Kumar (2005) Krishna et al. (2008) Kumar and Senapathi (2013) Indirect effects of plant height on grain yield through Character Positive indirect effect Negative indirect effect Days to 50 per cent flowering Gupta et al. (1998) Madhavilatha (2002) Borbora et al. (2005) Krishna Naik et al. (2005) Manonmani and Ranganathan (2006) Swain and Reddy (2006) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Yadav et al. (2010) Akhtar et al. (2011) Selvaraj et al. (2011) Kumar and Senapathi (2013) Tirumala Rao et al. (2014) Panicle length Nagajyothi (2001) Tara Satyavathi et al. (2001) Borbora et al. (2005) Chitra et al. (2005) Krishna Veni and Shobha Rani (2005) Vinothini and Ananda Kumar (2005) Krishna Naik et al. (2005) Manna et al. (2006) Malini et al. (2007) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Yugandhar Reddy et al. (2008) Yadav et al. (2010) Chakraborty et al. (2010) Selvaraj et al. (2011) Ravindra Babu et al. (2012) Venkanna et al. (2014) Number of productive tillers per plant Valarmathi and Leenakumary (1998) Janardhanam et al. (2001) Nagajyothi (2001) Madhavilatha (2002) Eradasappa et al. (2007) Manonmani and Ranganathan (2006) Panwar and Mashiat Ali (2007) Swain and Reddy (2006) Krishna et al. (2008) Satish Chandra et al. (2009) Sinha et al. (1999) Kavitha and Sree Rama Reddi (2001) Chitra et al. (2005) Vinothini and Ananda Kumar (2005) Malini et al. (2007) Anbumalarmathi and Nadarajan (2008) Satish Chandra et al. (2009) Ravindra Babu et al. (2012) Imad Naseem et al. (2014) Nayak et al. (2001) Madhavilatha (2002) Manonmani and Ranganathan (2006) Eradasappa et al. (2007) Kumar and Senapathi (2013) Imad Naseem et al. (2014) Tirumala Rao et al. (2014) Ganesan et al. (1997) Nayak et al. (2001) Tara Satyavathi et al. (2001) Chitra et al. (2005) Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Vinothini and Ananda Kumar (2005) Manna et al. (2006) Yugandhar Reddy et al. (2008) Ravindra Babu et al. (2012)

73 Table (Cont.) Character Positive indirect effect Negative indirect effect Yadav et al. (2010) Akhtar et al. (2011) Selvaraj et al. (2011) Kumar and Senapathi (2013) Tirumala Rao et al. (2014) Imad Naseem et al. (2014) Venkanna et al. (2014) Panicle weight Kumar and Senapati (2013) Venkanna et al. (2014) Number of filled grains per panicle 1000-grain weight Deb Choudhary and Das (1998) Madhavilatha (2002) Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Manonmani and Ranganathan (2006) Eradasappa et al. (2007) Malini et al. (2007) Panwar and Mashiat Ali (2007) Anbumalarmathi and Nadarajan (2008) Satish Chandra et al. (2009) Yadav et al. (2010) Akhtar et al. (2011) Selvaraj et al. (2011) Imad Naseem et al. (2014) Sinha et al. (1999) Nagajyothi (2001) Madhavilatha (2002) Borbora et al. (2005) Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Vinothini and Ananda Kumar (2005) Manonmani and Ranganathan (2006) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Yugandhar Reddy et al. (2008) Satish Chandra et al. (2009) Akhtar et al. (2011) Selvaraj et al. (2011) Imad Naseem et al. (2014) Venkanna et al. (2014) Kernel length Krishna et al. (2008) Venkanna et al. (2014) Kernel breadth Krishna et al. (2008) Venkanna et al. (2014) Kernel L/B ratio Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Krishna et al. (2008) Manna et al. (2006) Swain and Reddy (2006) Sarker et al. (2013) Valarmathi and Leenakumari (1998) Suryanarayana (2000) Borbora et al. (2005) Chitra et al. (2005) Manna et al. (2006) Swain and Reddy (2006) Krishna et al. (2008) Chakraborty et al. (2010) Ravindra Babu et al. (2012) Imad Naseem et al. (2014) Venkanna et al. (2014) Tirumala Rao et al. (2014) Nayak et al. (2001) Chitra et al. (2005) Swain and Reddy (2006) Anbumalarmathi and Nadarajan (2008) Krishna et al. (2008) Yadav et al. (2010) Chakraborty et al. (2010) Ravindra Babu et al. (2012) Kumar and Senapathi (2013) Tirumala Rao et al. (2014) Kumar and Senapathi (2013) Kumar and Senapathi (2013) Kumar and Senapathi (2013) Venkanna et al. (2014) Indirect effects of panicle length on grain yield through Character Positive indirect effect Negative indirect effect Days to 50 per cent flowering Bala (2001) Kavitha and Sree Rama Reddi (2001) Madhavilatha (2002) Krishna Naik et al. (2005) Manonmani and Ranganathan (2006) Debchoudhury and Das (1998) Borbora et al. (2005) Chitra et al. (2005) Vinothini and Ananda Kumar (2005) Krishna et al. (2008)

74 Table (Cont.) Character Positive indirect effect Negative indirect effect Eradasappa et al. (2007) Malini et al. (2007) Panwar and Mashiat Ali (2007) Yadav et al. (2010) Selvaraj et al. (2011) Venkanna et al. (2014) Ravindra Babu et al. (2012) Kumar and Senapathi (2013) Imad Naseem et al. (2014) Tirumala Rao et al. (2014) Plant height Valarmathi and Leenakumari (1998) Bala (2001) Nayak et al. (2001) Madhavilatha (2002) Chitra et al. (2005) Krishna Veni and Shobha Rani (2005) Manonmani and Ranganathan (2006) Eradasappa et al. (2007) Malini et al. (2007) Yugandhar Reddy et al. (2008) Chakraborty et al. (2010) Selvaraj et al. (2011) Kumar and Senapathi (2013) Tirumala Rao et al. (2014) Number of productive tillers per plant Valarmathi and Leenakumari (1998) Bala (2001) Nayak et al. (2001) Krishna Veni and Shobha Rani (2005) Manonmani and Ranganathan (2006) Eradasappa et al. (2007) Yugandhar Reddy et al. (2008) Yadav et al. (2010) Selvaraj et al. (2011) Venkanna et al. (2014) Panicle weight Manna et al. (2006) Kumar and Senapati (2013) Sarker et al. (2013) Venkanna et al. (2014) Number of filled grains per panicle Debchoudhury and Das (1998) Nayak et al. (2001) Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Manna et al. (2006) Manonmani and Ranganathan (2006) Eradasappa et al. (2007) Malini et al. (2007) Krishna et al. (2008) Yadav et al. (2010) Kumar and Senapathi (2013) Imad Naseem et al. (2014) Tirumala Rao et al. (2014) Venkanna et al. (2014) 1000-grain weight Nagajyothi (2001) Madhavilatha (2002) Krishna Naik et al. (2005) Tara Satyavathi et al. (2001) Janardhanam et al. (2001) Borbora et al. (2005) Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Manna et al. (2006) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Yadav et al. (2010) Ravindra Babu et al. (2012) Imad Naseem et al. (2014) Venkanna et al. (2014) Tara Satyavathi et al. (2001) Madhavilatha (2002) Chitra et al. (2005) Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Manna et al. (2006) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Chakraborty et al. (2010) Ravindra Babu et al. (2012) Kumar and Senapathi (2013) Imad Naseem et al. (2014) Tirumala Rao et al. (2014) Borbora et al. (2005) Chitra et al. (2005) Vinothini and Ananda Kumar (2005) Panwar and Mashiat Ali (2007) Chakraborty et al. (2010) Selvaraj et al. (2011) Ravindra Babu et al. (2012) Nayak et al. (2001) Borbora et al. (2005) Chitra et al. (2005)

75 Table (Cont.) Character Positive indirect effect Negative indirect effect Krishna Veni and Shobha Rani (2005) Vinothini and Ananda Kumar (2005) Yugandhar Reddy et al. (2008) Chakraborty et al. (2010) Yadav et al. (2010) Selvaraj et al. (2011) Kumar and Senapathi (2013) Imad Naseem et al. (2014) Tirumala Rao et al. (2014) Manonmani and Ranganathan (2006) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Satish Chandra et al. (2009) Ravindra Babu et al. (2012) Venkanna et al. (2014) Kernel length Kumar and Senapathi (2013) Krishna et al. (2008) Venkanna et al. (2014) Kernel breadth Krishna et al. (2008) Kumar and Senapathi (2013) Venkanna et al. (2014) Kernel L/B ratio Krishna Naik et al. (2005) Kumar and Senapathi (2013) Vinothini and Ananda Kumar (2005) Krishna et al. (2008) Indirect effects of number of productive tillers per plant on grain yield through Character Positive indirect effect Negative indirect effect Days to 50 per cent flowering Nayak et al. (2001) Madhavilatha (2002) Vinothini and Ananda Kumar (2005) Eradasappa et al. (2007) Manonmani and Ranganathan (2006) Panwar and Mashiat Ali (2007) Anbumalarmathi and Nadarajan (2008) Krishna et al. (2008) Satish Chandra et al. (2009) Akhtar et al. (2011) Ravindra Babu et al. (2012) Kumar and Senapathi (2013) Imad Naseem et al. (2014) Tirumala Rao et al. (2014) Plant height Janardhanam et al. (2001) Nagajyothi (2001) Madhavilatha (2002) Chitra et al. (2005) Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Manonmani and Ranganathan (2006) Swain and Reddy (2006) Eradasappa et al. (2007) Anbumalarmathi and Nadarajan (2008) Krishna et al. (2008) Chakraborty et al. (2010) Yadav et al. (2010) Akhtar et al. (2011) Selvaraj et al. (2011) Imad Naseem et al. (2014) Kavitha and Sree Rama Reddi (2001) Chitra et al. (2005) Krishna Naik et al. (2005) Swain and Reddy (2006) Yadav et al. (2010) Selvaraj et al. (2011) Krishna Veni and Shobha Rani (2005) Manna et al. (2006) Panwar and Mashiat Ali (2007) Yugandhar Reddy et al. (2008) Satish Chandra et al. (2009) Kumar and Senapathi (2013) Tirumala Rao et al. (2014)

76 Table (Cont.) Character Positive indirect effect Negative indirect effect Panicle length Gupta et al. (1998) Nagajyothi (2001) Madhavilatha (2002) Chitra et al. (2005) Krishna Veni and Shobha Rani (2005) Krishna et al. (2008) Yugandhar Reddy et al. (2008) Selvaraj et al. (2011) Imad Naseem et al. (2014) Panicle weight Swain and Reddy (2006) Sarker et al. (2013) Venkanna et al. (2014) Number of filled grains per panicle Gupta et al. (1998) Janardhanam et al. (2001) Tara Satyavathi et al. (2001) Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Vinothini and Ananda Kumar (2005) Manonmani and Ranganathan (2006) Swain and Reddy (2006) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Akhtar et al. (2011) Selvaraj et al. (2011) Kavitha and Sree Rama Reddi (2001) Nayak et al. (2001) Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Manna et al. (2006) Manonmani and Ranganathan (2006) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Satish Chandra et al. (2009) Chakraborty et al. (2010) Yadav et al. (2010) Ravindra Babu et al. (2012) Kumar and Senapathi (2013) Tirumala Rao et al. (2014) Manna et al. (2006) Kumar and Senapati (2013) Valarmathi and Leenakumari (1998) Nayak et al. (2001) Madhavilatha (2002) Chitra et al. (2005) Manna et al. (2006) Anbumalarmathi and Nadarajan (2008) Chakraborty et al. (2010) Yadav et al. (2010) Kumar and Senapathi (2013) Imad Naseem et al. (2014) 1000-grain weight Nagajyothi (2001) Tara Satyavathi et al. (2001) Chitra et al. (2005) Krishna Veni and Shobha Rani (2005) Vinothini and Ananda Kumar (2005) Manonmani and Ranganathan (2006) Panwar and Mashiat Ali (2007) Anbumalarmathi and Nadarajan (2008) Krishna et al. (2008) Nayak et al. (2001) Madhavilatha (2002) Krishna Naik et al. (2005) Swain and Reddy (2006) Eradasappa et al. (2007) Yugandhar Reddy et al. (2008) Chakraborty et al. (2010) Yadav et al. (2010) Akhtar et al. (2011) Selvaraj et al. (2011) Ravindra Babu et al. (2012) Kumar and Senapathi (2013) Imad Naseem et al. (2014) Tirumala Rao et al. (2014) Kernel length Krishna et al. (2008) Kumar and Senapathi (2013) Kernel breadth Krishna et al. (2008) Kumar and Senapathi (2013) Kernel L/B ratio Vinothini and Ananda Kumar (2005) Kumar and Senapathi (2013) Krishna Naik et al. (2005) Krishna et al. (2008)

77 Indirect effects of Panicle weighton grain yield through Character Positive indirect effect Negative indirect effect Days to 50 per cent flowering Nayak et al. (2001) Madhavilatha (2002) Kumar and Senapati (2013) Sarker et al. (2013) Plant height Nagajyothi (2001) Madhavilatha (2002) Manna et al. (2006) Venkanna et al. (2014) Number of productive tillers per plant Tara Satyavathi et al. (2001) Nagajyothi (2001) Manna et al. (2006) Swain and Reddy (2006) Sarker et al. (2013) Venkanna et al. (2014) Panicle length Nagajyothi (2001) Nayak et al. (2001) Kumar and Senapati (2013) Sarker et al. (2013) Venkanna et al. (2014) Number of grains per panicle Tara Satyavathi et al. (2001) Madhavilatha (2002) Manna et al. (2006) Swain and Reddy (2006) Sinha et al.,(1999) Swain and Reddy (2006) Venkanna et al. (2014) Ganesan et al. (1997) Swain and Reddy (2006) Kumar and Senapati (2013) Sarker et al. (2013) Kavitha and Sree Rama Reddi (2001) Madhavilatha (2002) Kumar and Senapati (2013) Gupta et al. (1998) Madhavilatha (2002) Reddy et al. (1997) Nayak et al. (2001) Manna et al. (2006) Kumar and Senapati (2013) Sarker et al. (2013) Venkanna et al. (2014) 1000 grain weight Sarker et al. (2013) Venkanna et al. (2014) Swain and Reddy (2006) Kumar and Senapati (2013) Kernel length Kumar and Senapati (2013) Venkanna et al. (2014) Kernel breadth Venkanna et al. (2014) Kumar and Senapati (2013) Kernel L/B ratio Venkanna et al. (2014) Kumar and Senapati (2013) Indirect effects of number of filled grains per panicle on grain yield through Character Positive indirect effect Negative indirect effect Days to 50 per cent flowering Gupta et al. (1998) Madhavilatha (2002) Borbora et al. (2005) Chitra et al. (2005) Krishna Naik et al. (2005) Manonmani and Ranganathan (2006) Eradasappa et al. (2007) Anbumalarmathi and Nadarajan (2008) Krishna et al. (2008) Satish Chandra et al. (2009) Chakraborty et al. (2010) Yadav et al. (2010) Venkanna et al. (2014) Tirumala Rao et al. (2014) Kavitha and Sree Rama Reddi (2001) Nayak et al. (2001) Vinothini and Ananda Kumar (2005) Swain and Reddy (2006) Malini et al. (2007) Panwar and Mashiat Ali (2007) Akhtar et al. (2011) Ravindra Babu et al. (2012) Kumar and Senapathi (2013) Imad Naseem et al. (2014)

78 Table (Cont.) Character Positive indirect effect Negative indirect effect Plant height Valarmathi and Leenakumari (1998) Nayak et al. (2001) Madhavilatha (2002) Chitra et al. (2005) Debchoudhury and Das (1998) Borbora et al. (2005) Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Krishna Veni and Shobha Rani (2005) Manonmani and Ranganathan (2006) Eradasappa et al. (2007) Malini et al. (2007) Panwar and Mashiat Ali (2007) Anbumalarmathi and Nadarajan (2008) Satish Chandra et al. (2009) Chakraborty et al. (2010) Yadav et al. (2010) Akhtar et al. (2011) Selvaraj et al. (2011) Tirumala Rao et al. (2014) Panicle length Borbora et al. (2005) Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Vinothini and Ananda Kumar (2005) Malini et al. (2007) Panwar and Mashiat Ali (2007) Selvaraj et al. (2011) Ravindra Babu et al. (2012) Tirumala Rao et al. (2014) Number of productive tillers per plant Valarmathi and Leenakumari (1998) Borbora et al. (2005) Krishna Veni and Shobha Rani (2005) Eradasappa et al. (2007) Manonmani and Ranganathan (2006) Swain and Reddy (2006) Anbumalarmathi and Nadarajan (2008) Chakraborty et al. (2010) Akhtar et al. (2011) Selvaraj et al. (2011) Kumar and Senapathi (2013) Panicle weight Manna et al. (2006) Swain and Reddy (2006) Kumar and Senapati (2013) 1000-grain weight Madhavilatha (2002) Chitra et al. (2005) Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Anbumalarmathi and Nadarajan (2008) Satish Chandra et al. (2009) Chakraborty et al. (2010) Akhtar et al. (2011) Selvaraj et al. (2011) Ravindra Babu et al. (2012) Kumar and Senapathi (2013) Manna et al. (2006) Swain and Reddy (2006) Krishna et al. (2008) Kumar and Senapathi (2013) Imad Naseem et al. (2014) Venkanna et al. (2014) Nayak et al. (2001) Madhavilatha (2002) Manna et al. (2006) Manonmani and Ranganathan (2006) Eradasappa et al. (2007) Krishna et al. (2008) Kumar and Senapathi (2013) Imad Naseem et al. (2014) Venkanna et al. (2014) Nayak et al. (2001) Madhavilatha (2002) Chitra et al. (2005) Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Manna et al. (2006) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Yadav et al. (2010) Tirumala Rao et al. (2014) Venkanna et al. (2014) Sarker et al. (2013) Venkanna et al. (2014) Tara Satyavathi et al. (2001) Borbora et al. (2005) Vinothini and Ananda Kumar (2005) Manonmani and Ranganathan (2006) Swain and Reddy (2006) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Krishna et al. (2008) Yadav et al. (2010) Imad Naseem et al. (2014) Tirumala Rao et al. (2014) Venkanna et al. (2014) Kernel length Kumar and Senapathi (2013) Krishna et al. (2008) Venkanna et al. (2014)

79 Table (Cont.) Character Positive indirect effect Negative indirect effect Kernel breadth Kumar and Senapathi (2013) Krishna et al. (2008) Venkanna et al. (2014) Kernel L/B ratio Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Krishna et al. (2008) Kumar and Senapathi (2013) Venkanna et al. (2014) Indirect effects of 1000-grain weight on grain yield through Character Positive indirect effect Negative indirect effect Days to 50 per cent flowering Madhavilatha (2002) Krishna Naik et al. (2005) Manonmani and Ranganathan (2006) Swain and Reddy (2006) Eradasappa et al. (2007) Panwar and Mashiat Ali (2007) Anbumalarmathi and Nadarajan (2008) Satish Chandra et al. (2009) Imad Naseem et al. (2014) Venkanna et al. (2014) Plant height Nagajyothi (2001) Madhavilatha (2002) Krishna Veni and Shobha Rani (2005) Manonmani and Ranganathan (2006) Eradasappa et al. (2007) Anbumalarmathi and Nadarajan (2008) Krishna et al. (2008) Yugandhar Reddy et al. (2008) Selvaraj et al. (2011) Imad Naseem et al. (2014) Tirumala Rao et al. (2014) Panicle length Nayak et al. (2001) Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Vinothini and Ananda Kumar (2005) Manonmani and Ranganathan (2006) Eradasappa et al. (2007) Krishna et al. (2008) Yugandhar Reddy et al. (2008) Chakraborty et al. (2010) Selvaraj et al. (2011) Ravindra Babu et al. (2012) Imad Naseem et al. (2014) Tirumala Rao et al. (2014) Number of productive tillers per plant Nagajyothi (2001) Krishna Veni and Shobha Rani (2005) Vinothini and Ananda Kumar (2005) Manonmani and Ranganathan (2006) Panwar and Mashiat Ali (2007) Anbumalarmathi and Nadarajan (2008) Krishna et al. (2008) Imad Naseem et al. (2014) Kumar and Senapathi (2013) Sinha et al. (1999) Borbora et al. (2005) Chitra et al. (2005) Vinothini and Ananda Kumar (2005) Krishna et al. (2008) Chakraborty et al. (2010) Selvaraj et al. (2011) Ravindra Babu et al. (2012) Kumar and Senapathi (2013) Tirumala Rao et al. (2014) Borbora et al. (2005) Chitra et al. (2005) Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Swain and Reddy (2006) Panwar and Mashiat Ali (2007) Satish Chandra et al. (2009) Yadav et al. (2010) Ravindra Babu et al. (2012) Venkanna et al. (2014) Gupta et al. (1998) Madhavilatha (2002) Borbora et al. (2005) Chitra et al. (2005) Panwar and Mashiat Ali (2007) Satish Chandra et al. (2009) Yadav et al. (2010) Venkanna et al. (2014) Madhavilatha (2002) Krishna Naik et al. (2005) Swain and Reddy (2006) Eradasappa et al. (2007) Yugandhar Reddy et al. (2008) Satish Chandra et al. (2009) Yadav et al. (2010) Chakraborty et al. (2010) Selvaraj et al. (2011) Tirumala Rao et al. (2014)

80 Table (Cont.) Character Positive indirect effect Negative indirect effect Panicle weight Kumar and Senapati (2013) Swain and Reddy (2006) Sarker et al. (2013) Venkanna et al. (2014) Number of filled grains per panicle Tara Satyavathi et al. (2001) Madhavilatha (2002) Borbora et al. (2005) Krishna Naik et al. (2005) Krishna Veni and Shobha Rani (2005) Vinothini and Ananda Kumar (2005) Panwar and Mashiat Ali (2007) Satish Chandra et al. (2009) Selvaraj et al. (2011) Ravindra Babu et al. (2012) Kumar and Senapathi (2013) Imad Naseem et al. (2014) Venkanna et al. (2014) Kernel length Reddy et al. (1997) Krishna et al. (2008) Kernel breadth Ramesh Babu (1999) Madhavilatha (2002) Krishna et al. (2008) Kernel L/B ratio Nagajyothi (2001) Tara Satyavathi et al. (2001) Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Krishna et al. (2008) Kumar and Senapathi (2013) Nayak et al. (2001) Chitra et al. (2005) Manonmani and Ranganathan (2006) Swain and Reddy (2006) Eradasappa et al. (2007) Anbumalarmathi and Nadarajan (2008) Krishna et al. (2008) Yadav et al. (2010) Chakraborty et al. (2010) Tirumala Rao et al. (2014) Ganesan et al. (1997) Madhavilatha (2002) Kumar and Senapathi (2013) Venkanna et al. (2014) Sinha et al. (1999) Kumar and Senapathi (2013) Venkanna et al. (2014) Madhavilatha (2002) Venkanna et al. (2014) Indirect effects of kernel length on grain yield through Character Positive indirect effect Negative indirect effect Days to 50 per Nayak et al. (2001) Sinha et al. (1999) cent flowering Madhavilatha (2002) Kumar and Senapathi (2013) Krishna et al. (2008) Plant height Reddy et al. (1997) Nagajyothi (2001) Madhavilatha (2002) Kumar and Senapathi (2013) Venkanna et al. (2014) Panicle length Nagajyothi (2001) Nayak et al. (2001) Kumar and Senapathi (2013) Venkanna et al. (2014) Number of productive tillers per plant Nagajyothi (2001) Tara Satyavathi et al. (2001) Panicle weight Manna et al. (2006) Swain and Reddy (2006) Kumar and Senapati (2013) Venkanna et al. (2014) Venkanna et al. (2014) Ganesan et al. (1997) Krishna et al. (2008) Gupta et al. (1998) Madhavilatha (2002) Krishna et al. (2008) Kavitha and Sree Rama Reddi (2001) Madhavilatha (2002) Krishna et al. (2008) Kumar and Senapathi (2013)

81 Table (Cont.) Character Positive indirect effect Negative indirect effect Number of filled grains per panicle Tara Satyavathi et al. (2001) Madhavilatha (2002) Krishna et al. (2008) 1000 grain weight Kumar and Senapathi (2013) Venkanna et al. (2014) Kernel breadth Ramesh Babu (1999) Madhavilatha (2002) Kumar and Senapathi (2013) Venkanna et al. (2014) Kernel L/B ratio Nagajyothi (2001) Tara Satyavathi et al. (2001) Kumar and Senapathi (2013) Venkanna et al. (2014) Reddy et al. (1997) Nayak et al. (2001) Kumar and Senapathi (2013) Venkanna et al. (2014) Krishna et al. (2008) Sinha et al. (1999) Krishna et al. (2008) Madhavilatha (2002) Krishna et al. (2008) Indirect effects of kernel breadth on grain yield through Character Positive indirect effect Negative indirect effect Days to 50 per cent flowering Nayak et al. (2001) Madhavilatha (2002) Plant height Reddy et al. (1997) Nagajyothi (2001) Madhavilatha (2002) Krishna et al. (2008) Kumar and Senapathi (2013) Panicle length Nagajyothi (2001) Nayak et al. (2001) Krishna et al. (2008) Number of productive tillers per plant Kumar and Senapathi (2013) Tara Satyavathi et al. (2001) Nagajyothi (2001) Krishna et al. (2008) Kumar and Senapathi (2013) Panicle weight Kumar and Senapathi (2013) Venkanna et al. (2014) Number of filled Tara Satyavathi et al. (2001) grains per panicle Madhavilatha (2002) Sinha et al. (1999) Krishna et al. (2008) Kumar and Senapathi (2013) Venkanna et al. (2014) Ganesan et al. (1997) Venkanna et al. (2014) Gupta et al. (1998) Madhavilatha (2002) Venkanna et al. (2014) Kavitha and Sree Rama Reddi (2001) Madhavilatha (2002) Venkanna et al. (2014) Nayak et al. (2001) Krishna et al. (2008) 1000 grain weight Krishna et al. (2008) Kumar and Senapathi (2013) Kumar and Senapathi (2013) Venkanna et al. (2014) Kernel length Reddy et al. (1997) Krishna et al. (2008) Kernel L/B ratio Nagajyothi (2001) Tara Satyavathi et al. (2001) Kumar and Senapathi (2013) Venkanna et al. (2014) Ganesan et al. (1997) Madhavilatha (2002) Kumar and Senapathi (2013) Venkanna et al. (2014) Madhavilatha (2002) Krishna et al. (2008)

82 Indirect effects of kernel L/B ratio on grain yield through Character Positive indirect effect Negative indirect effect Days to 50 per cent flowering Nayak et al. (2001) Madhavilatha (2002) Kumar and Senapathi (2013) Plant height Nagajyothi (2001) Madhavilatha (2002) Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Krishna et al. (2008) Panicle length Nagajyothi (2001) Nayak et al. (2001) Vinothini and Ananda Kumar (2005) Number of productive tillers per plant Krishna et al. (2008) Nagajyothi (2001) Tara Satyavathi et al. (2001) Krishna Naik et al. (2005) Panicle weight Kumar and Senapathi (2013) Venkanna et al. (2014) Number of filled Tara Satyavathi et al. (2001) grains per panicle Madhavilatha (2002) Kernel length Reddy et al. (1997) Krishna et al. (2008) Sinha et al. (1999) Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Krishna et al. (2008) Ganesan et al. (1997) Kumar and Senapathi (2013) Gupta et al. (1998) Madhavilatha (2002) Krishna Naik et al. (2005) Kumar and Senapathi (2013) Kavitha and Sree Rama Reddi (2001) Madhavilatha (2002) Vinothini and Ananda Kumar (2005) Krishna et al. (2008) Kumar and Senapathi (2013) Nayak et al. (2001) Krishna Naik et al. (2005) Vinothini and Ananda Kumar (2005) Krishna et al. (2008) Kumar and Senapathi (2013) Madhavilatha (2002) Kumar and Senapathi (2013) Kernel breadth Ramesh Babu (1999) Madhavilatha (2002) 1000 grain weight Krishna et al. (2008) Kumar and Senapathi (2013) Sinha et al. (1999) Krishna et al. (2008) Krishna Naik et al. (2005)

83 Chapter III MATERIALS AND METHODS The present investigation on GENETIC ANALYSIS OF QUANTITATIVE TRAITS IN AROMATIC RICE (Oryza sativa L.) was under taken to; 1. Determine the nature of gene action controlling quantitative traits (yield and grain quality) and components of genetic variance through diallel analysis involving aromatic as well non aromatic parents with special features. 2. Study the inheritance pattern and to find out the magnitude of inter-allelic interactions for quantitative traits through generation mean analysis. 3. Estimate the extent of heterosis for yield and yield components and quality traits. 4. Quantify the genetic variation, genetic advance and heritability for grain yield and its components and quality traits in F 2 and F 3 generations. 5. Estimate the heritability and genetic advance in superior crosses on cross wise basis. 6. Study the character association and direct and indirect effects between yield and yield attributing traits through simple correlations and path analysis. 3.1 LOCATION The present investigation was carried out at Agricultural Research Station, Kampasagar, Nalgodna district of Andhra Pradesh from Kharif 2011 to Rabi The site is located at an altitude of m above the MSL. Its geographical bearing is North latitude and East longitude. 3.2 EXPERIMENTAL MATERIAL Combining ability studies, Heterosis and Inbreeding depression: The experimental material for combining ability studies, heterosis and inbreeding depression comprised of eight rice genotypes viz., BPT 5204, Akshyadhan, NLR 145, PUSA 1121, RNR 2354, Sumathi, Improved Pusa Basmati and Basmati 370 and their 28 F 1 hybrids and 28 F 2 s. All the parents, F 1 s and F 2 s were evaluated at a time

84 in a single experiment during Kharif 2012 to estimate combining ability, heterosis and inbreeding depression. The details and the salient features of the experimental material are presented in the Table Generation mean analysis The same (eight) parents viz., BPT 5204, Akshyadhan, NLR 145, PUSA 1121, RNR 2354, Sumathi, Improved Pusa Basmati and Basmati 370 were again used for making selective independent fresh crosses to estimate the gene effects through generation mean analysis during Kharif BPT 5204 x Akshyadhan 2. BPT 5204 x Pusa BPT 5204 x Sumathi 4.Akshyadhan x NLR Akshyadhan x Pusa NLR 145 x Sumathi 7. RNR 2354 x Imp. Pusa Basmati 8. RNR 2354 x Basmati Sumathi x Imp. Pusa Basmati 10. Imp. Pusa Basmati x Basmati METHODS Development of F 1 hybrids Experimental Technique During Kharif, 2011 (June November), after thorough land preparation and puddling, the nurseries of eight parents were sown in the raised beds. Four sowings and transplantings of the parents were done at an interval of 10 days to ensure synchronous flowering for production of adequate crossed seed. Twenty eight days old seedlings were transplanted at a spacing of 20 x 15 cm, with each entry in 4 rows. Unpairedparent method of planting arrangement was used for making diallel crosses. Crosses were effected in a 8 x 8 diallel to produce 28 crosses without reciprocals Crop Management Fertilizers were applied to the main field at the rate of 100 kg Nitrogen, 60 kg Phosphorus and 40 kg Murate of potash ha -1. Nitrogen was applied in three split doses. One-fourth as basal, one-half at the time of active tillering stage and one-fourth at panicle initiation stage. Entire Phosphorus and Murate of Potash were applied as single dose in the last puddle. The recommended package of practices of ANGRAU with necessary plant protection measures were adopted to raise a healthy crop throughout the season.

85 Hybridization techniques (Experiment I) Clipping Crosses were effected by clipping method of emasculation as per the procedures described by Jennings et.al (1979). Healthy plants were uprooted, labelled and potted in the morning hours 3-4 day prior to emasculation into plastic buckets and were shifted to the net house. Primary tillers with healthy panicles were selected and the leaf sheath was separated carefully. Further, spikelets that had completed anthesis (nearly 1/3 rd from the top) if any and young spikelets at the bottom of the panicle were removed. Matured spikelets which were about to flower next day were used for crossing. Top one-quarter to one-half of the glumes of each spikelet was clipped off with fine scissors and the anthers from the fully matured spikelets were removed without causing any damage to stigma in the evening time. The panicle was then bagged with butter paper bag to avoid unwanted cross pollination and prevent dehydration and labelled properly. Pollination On the following morning (9am to 11am), panicles ready for anthesis were selected from healthy parents and brought to the crossing chamber, in which temperature, relative humidity and light conducive for anthesis were maintained. When the mature anthers of parent were ready for dehiscence, the female lines were brought inside the crossing chamber. Butter paper bags covering clipped panicles of the female parents were removed. Viable pollen from panicles of male parents was then gently shaken over the female parents until adequate pollen was deposited on the stigmas of the emasculated spikelets. The pollinated spikelets were then covered with fresh butter paper bags to prevent cross pollination. The female parents were labelled and fixed against the support of bamboo stakes. The process of pollination was continued up to AM. Crossed seeds were collected after four weeks from the plants maintained in the pots in the net house. The seeds were then sun dried, counted and placed in small labeled envelops for further use.

86 Advancing of F 1 to F 2 generation (Experiment II) The crop was raised in successive Rabi (December May) season. Crossed seeds of hybrids were treated with Carbendazim solution (0.1%) and kept for germination in Petri dishes. Satisfactory germination was observed on the 3 rd and 4 th day of soaking. The seedlings were transferred to small raised beds covered with a layer of sand, planted in lines and sufficient care was taken to avoid water logging and complete drying up of the nursery beds. Top dressing was given with urea and need based plant protection was under taken for raising healthy and vigorous seedlings. Such healthy, strong and vigorous seedlings of 30 days age were transplanted in the main field. The parent seed was soaked in water for 24 hours and then incubated for 48 hours. The germinated seedlings were transferred to wet beds and proper care was taken to raise a healthy nursery. All the entries after attaining an age of 28 days were transplanted in the main field in a randomized complete block design with three replications. Each entry was planted in one row of 3.0 m length. Single seedling was transplanted per hill by adopting a spacing of 20 x 15 cm and all recommended package of practices were followed to raise a healthy crop. Selfed plants were removed after confirmation of F 1 s. Selfed seed was obtained for all the 28 crosses and 8 parents. Thus, four basic generations, P 1, P 2, F 1 and F 2 were developed for each of the twenty eight crosses during Rabi, Raising Parents, F 1 s and F 2 s for combining ability, heterosis and inbreeding depression studies (Experiment III) During Kharif 2012 (June November) all the 28 F 1 s and F 2 s along with parents were evaluated for combining ability, heterosis and inbreeding depression. The material was planted in randomized block design replicated thrice. Parents and hybrids (F 1 s) were planted in one row of 3.0 m length adopting a spacing of 20 cm between the rows and 15 cm between the plants within a row. The F 2 s were planted in twelve rows each of 3.0 m length with a same spacing as in the case of parents and hybrids. The Parents, F 1 s and F 2 s were randomized within the group (P + F 1 + F 2 ) and each group was again randomized in each replication.

87 Raising Parents, F 1, F 2 and F 3 s for generation mean analysis (Experiment IV) During Rabi (December May), the F 1 s, F 2 s and F 3 s of ten selective crosses along with parents were studied for analysis of generation means and estimate genetic parameters. The material was planted in randomized block design replicated thrice. Parents and hybrids (F 1 s) were planted in one row of 3.0 m length adopting a spacing of 20 cm between the rows and 15 cm between the plants within a row. The F 2 s and F 3 s were planted in twelve rows each of 3.0 m length with a same spacing as in the case of parents and hybrids. The generations within each set of cross and crosses in RBD were randomized. Data recorded on 10 plants each in P 1, P 2, F 1 and 50 plants in F 2 and F 3 family in each replication. 3.4 OBSERVATIONS RECORDED Ten plants in parents and F 1 s, 50 in F 2 and F 3 were tagged at random for each entry in each replication. Observations were recorded for yield and yield attributing characters from these tagged competitive plants (avoiding self s in F 1 s if any) in all the genotypes in each replication. The data for the character, days to 50 per cent flowering was recorded on plot basis. The method of recording data for each trait is described below character wise Days to 50% flowering (DFF) The total numbers of days taken from the date of sowing to extrusion of the panicle tip above the sheath of the flag leaf in 50 per cent of plants in a plot Plant height (cm) The plant height was recorded by measuring the total height from the base of the plant to the tip of the main panicle and excluding awn if present and is expressed in cm Number of productive tillers per plant The number of productive tillers per plant, which bear panicle were recorded at the time of maturity Panicle length (cm) The length of panicles from main tiller from each plant was measured in centimeters from neck node to the tip of top most grain in a panicle and was expressed in cm.

88 3.4.5 Panicle weight (g) Ten representative panicles were selected and weighed in grams Number of filled grains per panicle Filled spikelets of all the randomly taken panicles were counted after recording the weight of each panicle and expressed as mean number grain weight (g) One thousand random filled grains were counted from a random sample of each entry in each replication and weighed with the help of electronic balance in grams Grain yield per plant (g) Panicles from a single plant were harvested at maturity, threshed, cleaned and dried to per cent moisture content and the weight was recorded in grams and expressed as average grain yield per plant Kernel length (mm) Ten polished kernels in Parents, F 1 s and 50 in F 2 s and F 3 s were randomly selected and length of the kernel was recorded in mm using dial micrometer. Same procedure was followed for each replication Kernel breadth (mm) Breadth of the kernel was recorded on the same polished kernels used for length in mm using Dial micrometer Kernel Length/Breadth ratio The L/B ratio was calculated using the following formula of Murthy and Govindaswamy (1967). Mean length of grain in mm L/B ratio = Mean breadth of grain in mm Kernel length after cooking (mm) Uniformly cooked grains at random from each sample were taken and length was measured to nearest millimeter on a graph sheet. Sampling size was same as in case of Kernel Length, Breadth and kernel L/B ratio Kernel elongation ratio The length of rice grains of each sample was measured before and after cooking and the elongation ratio was worked out following standard method of Verghese (1950) as modified by Murthy (1965). Mean length of cooked kernel in millimeters Elongation ratio = Mean length of milled kernel in millimeters

89 Head rice recovery The polished kernels were passed repeatedly through a rice grader having 5 mm grooves to separate the brokens from the head rice kernels. Full rice and a length of three-fourth kernels were taken as whole polished rice for computation. Head rice recovery (HRR) was calculated in percentage as: Weight of whole rice (g) Head rice Recovery (%) = Weight of paddy (g) 3.5 STATISTICAL PROCEDURES The data recorded on different traits were subjected to the following statistical analysis Analysis of variance i) RBD analysis The adopted design was Randomized Block Design (RBD) replicated thrice. The analysis of variance was carried out by the method adopted by Panse and Sukhatme (1985). Y ij = m + g i + v j + e ij Where, Y ij m g i v j e ij = Phenotypic observation of i th genotype in j th replication = General mean = Effect of i th genotype = Effect of j th replication = Random error The analysis of variance (ANOVA) was carried out for each character as indicated below ANOVA Source of variation d.f MS F calculated Replications (r) (r-l) Mr Mr/Me Treatments (t) (t-l) Mt Mt/Me Error (e) (r-l) (t-l) Me Total (rt-l)

90 where, r t Mr Mt Me = number of replications = number of treatments (genotypes) = mean sum of squares of replications = mean sum of squares of treatments = mean sum of squares of error d. f. = degrees of freedom MS = mean sum of squares The significance of mean sum of squares for each character was tested against the corresponding error degrees of freedom using F test (Fisher and Yates, 1967). SE(m) = (Me/r) 1/2 Where, Me r = Error mean sum of squares = Number of replications C.D = S.E (d) x t Where, S.E (d) = (2Me/r) 1/2 t = t table value at error degrees of freedom C.V = (S.D/ X) x 100 Where, S.D = Standard deviation of the population X = Population mean ii) Diallel analysis (Combining ability) The data obtained from F 1 s and parents were analysed as per Method II (F 1 s + parents) and Model I (fixed effect) of Griffing (1956) for combining ability. The mathematical model for combining ability is 1 X ij = μ + g i + g j + S ij Σ k Σ l e ijkl bc i, j = 1,. p k = 1,... b L = 1,... c

91 Where p = b = c = μ = g i = g j = S ij = S ij = e ijkl = Number of varieties Number of blocks Number of observations on (i,j) th genotype in k th block Population mean gca effect of the i th parent gca effect of the j th parent sca effect of the cross between i th and j th parents such that S ji and Environment effect pertaining to the ijkl th observation on ij th individual in k th block with i th female parent and j th male parent. The restrictions imposed in this model are Σe i g i = 0 e j S ij + S ji = 0 (for each i) Analysis of variance Source Df S.S. M.S.S Expected mean square General Combining Ability (P-1) Sg Mg σ 2 e + (P+2) (1/P-1) Σ i g i 2 Specific Combining Ability P (P-1)/2 Ss Ms σ 2 e + Error M Se Me σ 2 e 2 P( P I) Σ i Σ j S ij 2 S g = 1 [Σ i (x i + x ii ) x 2.. ] ( P + 2) P Ss = Σ i Σ sj x ij 2-1 ( P + 2) 2 2 Σ i (x i + x ii ) 2 + x... ( P + 1)( P + 2) Where, Sg = Ss = P = x i = x ii = x = Sum of square due to GCA Sum of square due to SCA Number of parents Total of the array involving i th parent Mean value of i th parent Grand total of ½ (p) (p-1) progenies

92 x ij = M = Progeny mean value in the diallel table Degree of freedom for error Mean square gca to sca variance ratio was calculated to know the type of gene action in the inheritance of that particular trait. Mg Me σ 2 gca = n + 2 σ 2 sca = Ms Me Estimation of gca and sca effects i) General combining ability effects of i th parent with restriction Σg i = g i = [Σ (x i + x ii ) - x ] ( P + 2) P ii) Specific combining ability effects of ij th cross: with restriction Σs ij + s ii = 0 g ij = Xij - 1 ( P + 2) (x i. + x ii + x j. + x jj ) + 2 ( P + 1)( P + 2) x Where, P, x ij, x i, x ii and x.. denotes the same term as mentioned earlier. Standard errors S.E.g i = S.E.S ii = P 2 ( 1) σ e ( P + 2) P ( P 1) 2 σ e ( P + 1)( P + 2) 2 P ( P + 2) 2 S.E.S ij = σ e( i # j) ( P + 1)( P + 2) Each gca and sca value was tested against zero for its significance by `t test. t = (g-0) / SE (g i ) or t = (S ij = 0 / SE (s ij ) Variability, Heritability and Genetic Advance These parameters were estimated in F 2 as well as in F 3 generation separately by utilizing crosswise mean values of RBD and considering each generation as whole population to have a comparison between two generations (F 2 and F 3 ).

93 Genotypic and Phenotypic Co-efficients of Variation The genotypic and phenotypic coefficients of variation were calculated according to the formula given by Falconer (1981). Genotypic standard deviation Genotypic Co-efficient of Variation (GCV) = x 100 Mean Phenotypic standard deviation Phenotypic Co-efficient of Variation (PCV) = x 100 Mean Categorization of the range of variation was effected as proposed by Sivasubramanian and Madhavamenon (1973). Less than 10% : Low 10-20% : Moderate More than 20% : High Heritability Heritability in the broad sense refers to the proportion of genotypic variance to the total observed variance in the total population. Heritability (h 2 ) in the broad sense was calculated according to the formula given by Allard (1960). Where, h 2 (bs) = σ 2 s g = σ 2 g h 2 (bs) = σ 2 p heritability in broad sense genotypic variance σ 2 s p = phenotypic variance (σ 2 s g + σ 2 s e) Where, ½D + ½H 1 - ½H 2 - ½F h 2 (ns) = X 100 ½D + ½H 1 - ¼H 2 - ½F + E h 2 (ns) is heritability in narrow sense D is additive genetic variance H is non additive variance E is error variance

94 As suggested by Johnson et al. (1955) h 2 estimates were categorized as: Low : 0-30% Medium : above 30-60% High : above 60% Genetic Advance Genetic advance refers to the expected gain or improvement in the next generation by selecting the superior individuals under certain amount of selection pressure. From the heritability estimates the genetic advance was estimated by the following formula given by Burton (1952). Where, GA = K. h 2 (bs). σ 2 p or K. h 2 (ns). σ 2 p GA = expected genetic advance K = Selection differential, the value of which is 2.06 at 5 per cent selection intensity σ 2 p = phenotypic standard deviation h 2 (bs) = heritability in broad sense h 2 (ns) = heritability in narrow sense In order to visualize the relative utility of genetic advance among the characters, genetic advance as per cent for mean was computed. GA Genetic advance as per cent of mean = x 100 Grand mean The range of genetic advance as per cent of mean was classified as suggested by Johnson et al. (1955). Low = Less than 10% Moderate = % High = More than 20% Crosswise genetic parameters in 11 crosses In addition to the above attempt, 11 crosses showing less inbreeding depression and high per se performance for quality or yield or both in F 2 generation were selected and genetic parameters were estimated cross wise. Good performance of individual crosses for a particular trait in F 2 may be mostly due to additive gene effects and

95 estimation of genetic parameters like heritability and genetic advance based on genotypic variance too would be highly useful for selection of superior genotypes. For estimation of crosswise information the environmental variation was estimated by using the formulae (Allard, 1960): V E = VP 1 +VP 2 +VF V g = V P -V E Vg h 2 (bs) = --- x 100 Vp Where, Vg = Genotypic variation Vp = Phenotypic variation Estimation of heterosis Heterosis was estimated in 28 hybrids for 14 characters using the following formulae Heterosis over mid parent Heterosis was expressed as per cent increase or decrease observed in the F 1 over the mid-parent as per the following formula. F Heterosis (%) (H 1 ) = 1 MP x100 MP Where, F 1 MP = Mean of F 1 = Mean of parents Heterosis over better parent Heterobeltiosis was expressed as per cent increase or decrease observed in F 1 over the better parent as per the formula of Liang et al. (1971). F1 BP Heterobeltiosis (%) (H 2 ) = x100 BP Where, BP = Mean of better parent (for the characters like days to 50% flowering, earliness is desirable so the early parents are taken as better parents).

96 Standard heterosis Standard or useful or commercial heterosis was expressed as per cent increase or decrease observed in F 1 over standard checks. F1 Mean of standard check Standard heterosis (H 3 ) = x100 Mean of standard check Inbreeding depression Inbreeding depression was expressed as per cent decrease observed in F 2 over F 1 F 1 F 2 Inbreeding depression (%) = X 100 F 1 Where, F 1 = Mean of F 1 F 2 = Mean of F Test of significance of heterosis To test the significance for different types of heterosis, SEs were calculated based on error mean squares (EMS) from the ANOVA tables consisting parents and crosses. The significance of heterosis viz., relative heterosis and heterobeltiosis was then tested by comparing the calculated t - value with the tabulated student s t -value for appropriate error degrees of freedom at 5 per cent and 1 per cent level of significance (0.05 and 0.01 level of probability), respectively. t cal for Heterosis = F 1 Mean of mid parents SE(d) t cal for Heterobeltiosis = F 1 better parent SE(d) Where, SE(d) = 2 EMS/ r EMS = Error mean of squares r = Number of replications t cal for Standard heterosis = F 1 Mean of check SEd SC Where, SEd SC = 2σe 2 / r

97 Least significant difference (critical difference) for heterosis The significance of the difference between two estimates of heterosis was tested by computing the least significant difference (LSD) by multiplying the SEd with the appropriate student s t value of respective error degrees of freedom at desired level of probability. CD = SEd x t table value at error degrees of freedom Simple Correlations The data on 11 characters were utilized for the computation of simple correlation coefficients between quality, yield and yield component characters for all the genotypes. The formula suggested by Snedecor and Cochran (1967) was followed. Cov (X i. X j ) r (X i. X j ) = (Var X i ). (Var X j ) Where, r (X i. X j ) Cov (X i. X j ) = Correlation coefficients between i th and j th character = Covariance between i th and j th character (Var X i ) (Var X j ) = Variance of i th and j th characters respectively To test the significance of simple correlation coefficients, the estimated values were compared with the table values of correlation coefficients (Fisher and Yates, 1967) at 5 per cent and 1 per cent levels of significance with (n-2) degrees of freedom, where n is the number of genotypes used in the experiment Path coefficient analysis Contribution of 13 component characters towards dependent character were calculated through path coefficient analysis as suggested by Wright (1921) and elaborated by Dewey and Lu (1959) based on simple correlations. r ly = P ly + r 12 P 2y + r 13 P 3y + + r 1y P Iy r 2y = P 2y P 1y + P 2y + r 23 P 3y + + r 2y P Iy : : : : : : : :

98 r Iy = r I1 P 1y + r I2 P 2y + r I3 P 3y + + P Iy Where, r 1y to r Iy = Coefficient of correlation between causal factor 1 to I and dependent character Y. r 12 to r I-II = Coefficient of correlation among causal factors P 1y to P Iy = Direct effects of characters 1 to I on character Y A C B r 1y 1 r 12 r 13.. r 1i P 1y r 2y r 21 1 r 23.. r 2i P 2y r 3y r 31 r r3 i P 3y : : :r Iy r I1 r I2 r I3 1 P Iy Then B = [C] -1 A Where C -1 C11 C12 C13 C11 C 21 C 22 C 23 C 21 : : C I1 C I2 C I3 C Ii The matrix was inverted using generalized inverse (G inverse). Then, direct effects were calculated as follows: I P 1Y = Σ C 1i r iy i=1 I P 2Y = Σ C 2i r iy i=1 I P iy = Σ C ij r iy i=1 Residual effect (PR y ) which measures the contribution of the characters not considered in the casual scheme was obtained as, Residual effect (PR y ) = (1-r 2 ) 1/2 r 2 = (P 1y r 1y + P 2y r 2y P Iy r Iy )

99 3.5.7 Generation mean analysis The concept of Generation Mean Analysis (GMA) was developed by Hayman (1958) and Jinks and Jones (1958) for the estimation of genetic components of variation. Accordingly, the means were computed for each generation of P 1, P 2, F 1, F 2 and F 3 for each cross over three replications in the present study. The variance and corresponding standard errors of the means were computed from the deviations of the individual values obtained from individual plants for each of the generation in each cross. The experimental material (P 1, P 2, F 1, F 2, and F 3 ) for study of this aspect was planted during Rabi (December May) separately. The generations within each set of cross and crosses in RBD were randomized Scaling test Scaling tests developed by Mather (1949) and Hayman and Mather (1955) were used for knowing the presence or absence of non-allelic interactions. Scale C = 4F2 2F1 P1 P2 = 0 Scale D = 4F 3 2F 2 P 1 P 2 = 0 Where, P 1, P 2, F 1, F 2, and F 3 are means of different generations over the replications. The variances for C and D scales were calculated as follows: V C = 16V(F ) + 4V(F 1) + V(P 1) + V(P2 ) 2 = 0 V D = 16V(F 3 ) + 4V(F 2 ) + V(P 1 ) + V(P 2 ) = 0 Where, V C and V D are the variances of C and D VP 1, VP 2, VF 1, VF 2 and VF 3 are the variances of P 1, P 2, F 1, F 2, and F 3 generations, respectively. The standard error of C and D were worked out by taking the square root of respective variances. S.E for C scale = VC S.E for D scale = VD The t values were calculated by dividing the scale effects of by their respective standard errors. t cal for C-test = Scale C / S.E of C scale t cal for D-test = Scale D/ S.E of D scale

100 The calculated values of t are to be compared with t table values at 5 per cent and 1 per cent level of significance at their respective degrees of freedom. The significance of any scaling test indicates the presence of epistasis Joint Scaling test In addition to using C and D scales, data were further subjected to joint scaling test (Cavalli, 1952) with 5 generations to know the presence or absence of epistasis since it offers x 2 test with 2 d.f and many advantages were associated with this test. It was fitted into 3 parameter model, when x 2 value was significant it indicated that data does not fit into simple additive - dominance model and epistasis was present. The following procedure was followed to estimate the components in the joint scaling test. The parameters m, [d] and [h] estimated from the observed mean of the available types of generations were compared with expected values derived from the estimates of these three parameters. The five equations which are obtained by equating the observed family means to their expectations in terms of m, [d], [h], [i] and [l] were used for estimating these parameters. Since, the number of equations is higher than the number of parameters to be estimated, least square technique was followed. Further, the mean of various generations were not known with equal precision and hence, the generation means and their expectations were weighed, where the weight is estimated as 1 Weight = (Variance of generation mean) The weighed least square estimates of the three parameters were obtained from the three equations which were obtained after combining the five original equations and their weights. In order to assess first of these three equations, each of the original equation was multiplied by the coefficient of m which it contained and by its weight and all the six equations were then summed to give rise to a single equation. Similarly, the second and third equations were obtained by using the coefficients of [d] and [h] in turn the weights as the multipliers. These three simultaneous equations were solved by way of matrix inversion and the estimates of m, [d] and [h] were obtained. The adequacy of the additive-dominance model was tested by determining the expected values of five different generations with the help of estimates obtained from

101 m, [d] and [h] and following the comparison between observed and expected means of these generations. Five deviations between the observed and expected values of each generation were obtained and by squaring each of these deviations and multiplying those by their corresponding weights tested the goodness of fit. The products were summed over all five types of families and tested against the values of n-p degrees of freedom; that is 2 χ 2 6 ( O E) = = xw for(n p) d.f i 1 E where, Σ 6 i=1 = Represents the sum of all six products O = Observed mean generations E = Expected mean value of the generation W = Corresponding weight of the generation N = Number of equations and P = Number of parameters to be used Significance of x 2 at (n-p) degrees of freedom (2 d. f) indicated presence of epistasis which was further confirmation to the results obtained in scaling tests Components of generation means When the individual scales (C, D) as well the x 2 values of Joint Scaling Test were significant, the mean values over replication were used for the estimation of the different components of variance. Owing to presence of five generations (P 1, P 2, F 1, F 2, and F 3 ) in each cross, assuming digenic interactions, five parameter model (Jinks and Jones, 1958) was used to estimate the five genetic parameters viz., mean (m), additive gene effects (d), dominance gene effects (h) and two types of non-allelic gene interactions viz., additive additive (i) and dominance dominance (l). m = F 2 [ d ] = 1 1 P1 P2 2 2 [ h ] = 1 (4F1 + 12F2 16F3 ) 6 [ i ] = 1 1 P1 F2 + ( )( P1 P2 + h) l 2 4 [ l ] = 1 (16F 3 24F2 + 8F2 ) 3 where, P1, P2, F1, F2 and F3 are mean values of P 1, P 2, F 1, F 2 and F 3 generations, respectively.

102 Presence of epistasis was detected based on the criteria that characters showing significance for any of the scales (C or D or both) indicated the presence of epistasis. The significance of C alone was taken as presence of dominance dominance (l) type of non-allelic interaction. The significance of D alone was taken as additive additive type. Existence of both additive additive and dominance dominance types of gene interaction was considered when C and D scales were significant. If none of the scaling tests was significant, it was considered as the absence of epistatic gene action (Mather and Jinks, 1971). Difference between generation means was a prerequisite to proceed with the analysis of generation means Test of significance of various gene effects The test of significance of the gene effects was done using t test for which variance and standard error of each estimates were calculated using following equations. Vm = V F2 1 1 V(d) = V P1 + VP V(h) = (16V F V F VF 3) V(i) = V P1 + F 2 + ( V P1 + V P2 + V h ) + Vl V(l) = (256V F V F V F1) 9 Where, V(P 1 ), V(P 2 ), V(F 1 ), V(F 2 ) and V(F 3 )are the variance of P 1, P 2, F 1, F 2, and F 3 generations, respectively. The standard error of each of the gene effects was estimated as follows S.E (m) = Vm Vd S.E (d) = S.E (h) = Vh V S.E (i) = i V S.E (l) = l

103 The t values were worked out using following formulae t(m) = m / S.E (m) t(d) = d / S.E (d) t(h) = h / S.E (h) t(i) = i / S.E (i) t(l) = l / S.E (l) The significance for above parameter is tested with the help of t test. First standard error (S.E) is worked out for each component separately by taking the square root of the variance of the respective component. Then the t value is calculated for each component by dividing the gene effects of respective components by their S.E. The calculated value of t is compared with 1.96, which is the table value of t at 5 per cent level of significance. If the calculated value greater than 1.96, it is considered significant and vice versa (Singh and Chaudhary. 1985) Chi-square test 2 χ test was applied for testing the deviation of an observed from the expected means. Chi-square was calculated using the formula. Where, Σ( O E χ = E 2 2 ) O = Observed mean values E = Expected mean values = Summation of the data degree of freedom (d. f) in Where, n = number of generations P = number of components estimated 2 χ test is (n-p), which is 5-3 = 2 d.f After detecting epistasis, through C, D scales and joint scaling test, the m, d, h, i and l components were estimated in perfect fit solution of digenic interaction (5 parameter model of Jinks and Jones, 1958).

104 Table 3.1: Salient features of selected parents for crossing S. No GENOTYPE PARENTAGE SOURCE SALIENT FEATURES 1 BPT 5204 GEB 24 / TN -1 // Mahsuri 2 Akshyadhan BR /SC (DRR Dhan 35) NLR 145 CICA 4/IR (Swarnamukhi) 3-1//Tetep 4 PUSA 1121 Pusa / Pusa RNR 2354 RNR M7 / RNR Sumathi Chandan / Pak. (RNR 18833) Basmati 7 Improved Pusa PB 1 // PB 1 / IRBB Basmati 55 8 Basmati 370 Pure line selection from local basmati land races RRU, Bapatla Long duration, medium slender grain, semi dwarf and good grain quality. DRR, Medium duration, long bold grain, Hyderabad high yielding, resistant to neck blast, tolerant to Brown Plant Hopper. ARS, Nellore Long slender, Straw glume, days duration, Resistant to blast and tolerant to salinity DRR, Strongly aromatic, extra long Hyderabad slender grain, low gelatinization temperature, high cooked kernel elongation after cooking, days duration Rice Section, Short slender aromatic with ARI, medium duration Hyderabad Rice Section, Aromatic, extra long slender grain, ARI, days duration, resistant to Hyderabad blast. DRR, Semi-dwarf, long duration, Hyderabad Aromatic, extra long slender and translucent, awns present DRR, Tall, extra long slender grain, Hyderabad awns present

105 Chapter IV RESULTS AND DISCUSSION The results of the present study on Genetic analysis of quantitative traits in aromatic rice (Oryza sativa L.) are presented under the following heads. 4.1 Mean performance of parents and crosses 4.2 Study of heterosis and inbreeding depression 4.3 Combining ability analysis 4.4 Generation mean analysis 4.5 Estimates of mean, variability, heritability and genetic advance in F 2 and F 3 generations. 4.6 Estimation of heritability and genetic advance in superior crosses (Cross wise) 4.7 Character association and path coefficient analysis in F 2 and F 3 generations. 4.1 MEAN PERFORMANCE OF PARENTS AND CROSSES Analysis of variance The mean data on yield and yield attributes viz., days to 50 per cent flowering, plant height, number of productive tillers per plant, panicle length, panicle weight per plant, number of filled grains per panicle, 1000 grain weight, grain yield per plant, kernel length, kernel breadth, kernel L/B ratio, kernel length after cooking, kernel elongation ratio and head rice recovery, were collected and analyzed. Analysis of variance showed significant difference among the treatments (parents and crosses) for all the characters studied (Table 4.1). These results suggest that parents and their F 1 s exhibited high amount of genetic variation for most of the characters studied Study of Means The mean values of parents and their crosses (F 1 and F 2 ) on fourteen characters are presented in Table 4.2.

106 Days to 50% flowering The mean values of parents and crosses ranged from 79 to 121 with the general mean of 104 days. Among the parents Pusa 1121 flowered at 96 days while NLR 145 took 121 days and the mean was 108 days. The F 1 s, on an average took 97 days to attain 50 per cent flowering stage. The crosses viz., Pusa 1121 x Sumathi flowered early (79 days) while BPT 5204 x NLR 145 and BPT 5204 x RNR 2354 flowered late in 111 days. There was considerable reduction in F 1 s mean as compared to that of parents for days to 50 percent flowering, which is in desirable direction for improving earliness. The range was from 100 days (Pusa 1121 x Sumathi) to 120 days (BPT 5204 x NLR 145) in F 2 s with general mean of 110 days Plant height The general mean recorded for plant height ranged from 91 cm to 148 cm with a mean of cm (Table 4.2). The plant height for parents ranged from 97 cm in BPT 5204 to 138 cm in Sumathi, while in F 1 s the range was from 101 (BPT 5204 x Basmati 370) to 143 cm (Akshyadhan x Sumathi) with general mean of 117 cm. In case of F 2 s, the mean plant height ranged from 91 cm (BPT 5204 x Akshyadhan) to 148 cm (Akshyadhan x NLR 145) while plant height of the best check MTU 1010 was 91 cm Number of productive tillers per plant The productive tillers per plant is an important yield contributing trait which has direct effect on grain yield. The mean of productive tillers per plant was with a range of 7.0 to 15.8 (Table 4.2). The range varied from 8.5 (Basmati 370) to 14.5 tillers (Pusa 1121) among the parents and the parents averaged at 10.3 tillers. In F 1, it ranged from 7.0 (Pusa 1121 x Improved Pusa Basmati) to 12.1 (BPT 5204 x NLR 145). The mean performance of F 1 s was 9.7. Among F 2 s, the cross BPT 5204 x Pusa 1121 had the highest number of tillers with 15.1 whereas lowest number was observed in the case Akshyadhan x Basmati 370 (9.5) Panicle length A general mean of 26.4 cm was recorded for this character with a range from 19.8 to 32.3 cm. The parent, BPT 5204 had lowest panicle length of 19.8 cm, while Akshyadhan had highest panicle length of 29.3 cm. The parental mean was 25.1 cm. Among the F 1 hybrids, the range of panicle length was from 22.5 cm (BPT 5204 x NLR 145) to 32.3 cm (Sumathi x Improved Pusa Basmati) with a 27.6 cm average

107 mean. In F 2 s, highest value of 29.6 cm was observed in the case of NLR 145 x Pusa 1121 and lowest of 18.6 cm in Sumathi x Basmati 370 with a mean value 25.8 cm Panicle weight Panicle weight general mean varied from 0.9 g to 4.5 g with a general mean of 2.7 g (Table 4.2). Parents exhibited panicle weight ranging from 1.2 g (Pusa 1121) to 3.4 g (Akshyadhan) with a mean of 2.7 g. The F 1 hybrids exhibited panicle weight ranging from 1.5 g (NLR 145 x Pusa 1121) to 4.5 g (BPT 5204 x Basmati 370). Of all the F 2 s evaluated, Akshyadhan x Improved Pusa Basmati produced highest panicle yield of 3.2 g and lowest of 0.9 g by RNR 2354 x Sumathi and mean performance was 2.2 g Number of filled grains per panicle The number of filled grains per panicle varied from 34.4 to with a general mean of Parents viz., Akshyadhan and PUSA 1121 had highest and lowest grains of and 44.0 respectively with a parental mean of Among F 1 s, the cross, Pusa 1121 x Sumathi had highest number of grains of 348.1, while lowest number of grains was observed in NLR 145 x Pusa 1121 (48.9) with a mean of In F 2 s exhibited number of filled grains per panicle ranged from 34.4 (RNR 2354 x Sumathi) to (NLR 145 x RNR 2354) grain weight (g) The mean of 1000 grain weight varied from g to g with a general mean of g. The mean of parents was 19.8 g with highest value of g (Akshyadhan) and low value of g (BPT 5204). Among F 1 s, the range was from (BPT 5204 x RNR 2354) to g (Akshyadhan x Pusa 1121) with an average value of g. The mean of F 2 s was g with highest value of g (Akshyadhan x Pusa 1121) and low value of g (BPT 5204 x RNR 2354) Grain yield per plant (g) The grain yield per plant ranged from 7.3 g to 42.8 g with a general mean of 21.6 g. (Table 4.2). Among the parents, Akshyadhan yielded top with 28.6 g, whereas Improved Pusa Basmati recorded lowest yield of 10.5 g. Parents on an average yielded 18.8 g. The grain yield among the F 1 s varied from 10.0 g (NLR 145 x Pusa 1121) to 42.8 g (BPT 5204 x Akshyadhan) and exhibited an average yield of 24.2 g. The F 2 s exhibited an average yield of 19.9 g and the cross NLR 145 x Basmati 370 was the

108 highest yielding cross giving 27.6 g yield, while lowest yield of 7.3 g was obtained in case of RNR 2354 x Sumathi Kernel length (mm) The general mean for the trait was 6.13 mm and the range was from 4.79 to 8.32 mm. The parents recorded an average length of 6.17 mm. Highest kernel length of 7.36 mm was observed in case of Pusa 1121, while shortest length of 4.79 mm in BPT In F 1 s, the crosses Pusa 1121 x Sumathi and BPT 5204 x RNR 2354 had highest and lowest kernel length of 8.32 and 4.88 mm respectively with the mean of F 1 s being 6.32 mm. The F 2 s recorded an average length of 5.87 mm. Highest kernel length of 6.67 mm was observed in case of Pusa 1121 x Improved Pusa Basmati while shortest length of 5.01 mm in BPT 5204 x RNR Kernel breadth (mm) The general mean of Kernel breadth varied from 1.50 mm to 1.83 mm with a general mean of 1.66 mm. The mean value of parents was 1.68 mm with maximum breadth of 1.83 mm (Basmati 370) and lowest breadth of 1.54 mm (BPT 5204). In F 1 s, BPT 5204 x Pusa 1121 recorded highest value of 1.81 mm and BPT 5204 x RNR 2354 recorded lowest value of 1.50 mm and the average was 1.67 mm. Among F 2 s, the range was from 1.50 mm (BPT 5204 x NLR 145) to 1.78 mm (Akshyadhan x NLR 145) with an average value of 1.64 mm Kernel L/B ratio The L/B ratio ranged from 3.05 to 4.84 with a general mean of In parents, Improved Pusa Basmati and BPT 5204 had highest and lowest value of 4.30 and 3.11 respectively with mean of Among F 1 s, the range was from 3.05 (BPT 5204 x Akshyadhan) to 4.84 (Pusa 1121 x Sumathi) with an average value of The highest Kernel L/B ratio of 4.17 was observed in Pusa 1121 x Improved Pusa Basmati while lowest of 3.14 was noticed in BPT 5204 x Akshyadhan among the F 2 s with an average of Kernel length after cooking The parents, F 1 s and F 2 s showed an average kernel length after cooking of mm with a range of 7.60 mm to 14.0 mm (Table 4.2). Among the parents, lowest length was recorded by BPT 5204 (8.80 mm) and highest was recorded in case of Improved Pusa Basmati (14.00 mm) with a mean of mm. Similarly, among the F 1 s, the length after cooking ranged from 8.40 mm (BPT 5204 x Pusa 1121) to

109 13.80 mm (Akshyadhan x Basmati 370). F 2 s averaged 9.48 mm and maximum length after cooking was noticed in BPT 5204 x Pusa 1121 (11.87 mm) and a minimum of 8.58 mm in Akshyadhan x NLR Kernel elongation ratio Similarly, kernel elongation ratio is considered as an important cooking quality characteristic in quality rice breeding in view of consumer s preference. A genotype must be superior for physical and cooking quality for commercial success. For kernel elongation ratio a general mean of 1.67 with a range of 1.23 to 2.44 was recorded. However, the mean recorded for parents was 1.67 with a range of 1.39 (Pusa 1121) to 2.05 (Improved Pusa Basmati). Among the F 1 s, NLR 145 x Pusa 1121 recorded lowest elongation ratio 1.23 and highest was recorded in respect of BPT 5204 x RNR 2354 (2.44) with a mean of 1.73 (Table 4.2). The ratio for F 2 s ranged from 1.39 (NLR 145 x Sumathi) to 2.06 (BPT 5204 x Pusa 1121) with a mean of Head rice recovery per cent Head rice recovery (%) is one of the most important quality attributes that enhances the chances of commercial success of a variety. Sindhu (1989) reported that head rice recovery generally ranges from 25 to 65 per cent. In the present study also the mean values for head rice recovery per cent ranged from to per cent with a general mean of per cent. Among the parents, Akshyadhan recorded highest head rice recovery of per cent while Pusa 1121 recorded lowest of per cent with a parental mean of per cent. The F 1 hybrids recorded an average head rice recovery of per cent with BPT 5204 x NLR 145 recording highest value of per cent and BPT 5204 x RNR 2354 recording lowest head rice recovery percentage of Among F 2 s, the percentage range was from (Akshyadhan x Pusa 1121) to (Sumathi x Basmati 370) with an average percentage of

110 4.2 STUDY OF HETEROSIS AND INBREEDING DEPRESSION Heterosis The magnitude of heterosis exhibited by 28 hybrids was measured as per cent increase or decrease over the mean of parents (mid parental heterosis), over the better parent (heterobeltiosis) and over the checks (standard heterosis) using MTU 1010 for grain yield and Pusa 1121 for grain quality as best checks for all the fourteen characters and presented in the Table 4.3 to 4.7. The parents with lower values were considered as better parents for the estimation of heterosis for days to 50 per cent flowering, plant height and kernel breadth and negative heterosis as desirable. For the other characters, parents with higher estimates were considered as better parents. The results obtained on the magnitude of heterosis are presented below Days to 50% flowering High amount of heterosis registered in desirable direction for days to 50% flowering with all the crosses exhibiting significant negative heterosis except one cross (Table 4.3). The relative heterosis ranged from (Pusa 1121 x Sumathi) to 2.30 per cent (BPT 5204 x RNR 2354). Top five crosses were Pusa 1121 x Sumathi ( %), Pusa 1121 x Improved Pusa Basmati ( %), NLR 145 x Improved Pusa Basmati ( %), Sumathi x Improved Pusa Basmati ( %) and RNR 2354 x Improved Pusa Basmati ( %). Heterobeltiosis ranged from (Pusa 1121 x Sumathi) to 4.72 per cent (BPT 5204 x RNR 2354). For this trait 19 crosses showed significant negative heterobeltiosis, while only two crosses showed positive heterobeltiosis. Higher magnitudes of negative heterosis for earliness was reported by Alam et al. (2004), Gouri Shankar et al. (2010), Kumar Babu et al. (2010), Palaniraja et al. (2010) and Tiwari et al. (2011) and in the case of present study, indicating dominance nature of minus genes for earliness Plant height Negative heterosis is always preferred to evolve dwarf and semi dwarf varieties for general cultivation especially in irrigated ecosystem with high input management, which is evident from the success of green revolution. These

111 varieties are less prone to lodging (Janardhanam et al. 2001a). The average heterosis ranged from to per cent and heterobeltiosis ranged from to 9.90 per cent (Table 4.3). Seven hybrids exhibited significant negative heterosis ranging from (Pusa 1121 x Sumathi) to (NLR 145 x Basmati 370) per cent and were shorter than their mid parents. These finding have correlation with those of Bhave et al. (2002) and Sarial et al. (2006). For this trait, F 1 s of only two crosses Pusa 1121 x Sumathi (-11.99) and Pusa 1121 x Basmati 370 (-8.46) were shorter than their better parents and exhibited significant negative heterobeltiosis. Standard heterosis ranged from to and all hybrids exhibited significant and positive standard heterosis over the check MTU 1010, which is confirmed as best check for yield and earliness (Anju Chaudhary et al. 2007, Deoraj et al and Palaniraja et al. 2010) Number of productive tillers per plant Yield barrier can be broken either by production of higher biomass or the harvest index. Number of effective tillers per plant play most crucial role for higher gains on total biomass and yield as well and the range varied from to per cent, to per cent and from to per cent for relative, better parental and standard heterosis respectively (Table 4.3). Out of 28 crosses, six hybrids registered significant values over mid parent and only one cross over better parent. The cross, NLR 145 x Basmati 370 exhibited highest positive significant heterosis over better parent (20.52 %), whereas in contrast, Pusa 1121 x Improved Pusa Basmati registered highest significant negative heterosis over better parent ( %). In case of standard heterosis, ten crosses registered significant positive values over the check MTU 1010 with a range of (Pusa 1121 x Improved Pusa Basmati) to (BPT 5204 x NLR 145), indicating a good scope for genetical improvement of this trait through adopting an appropriate method of breeding. Earlier, Lokaprakash et al. (1992), Reddy and Nerkar (1995), Singh et al. (2006b), Gouri Shankar et al. (2010) and Sharma et al. (2013) also reported both positive and negative heterosis as in the case of present study suggesting methods of exploiting both additive and non-additive gene effects.

112 Panicle length Generally, long and compact panicle has higher number of grains per panicle resulting into higher productivity, provided sterility of spikelet s is taken care off, thus positive heterosis for panicle length also highly desirable (Tiwari et al. 2011). The average heterosis ranged from to per cent and heterobeltiosis ranged from to per cent (Table 4.4). Twenty hybrids were significantly superior over the mid parents with a positive range varying from 6.53 (Pusa 1121 x Basmati 370) to per cent (Pusa 1121 x RNR 2354) indicating mostly additive nature of gene actions. Patil et al. (2003), Verma et al. (2004) and Eradasappa et al. (2007) also were of similar opinion. Six hybrids recorded significant positive heterobeltiosis with a range of to per cent in cross combinations Akshyadhan x Improved Pusa Basmati and Pusa 1121 x RNR 2354 respectively, while seven crosses expressed significant negative heterosis. Standard heterosis ranged from 7.93 to per cent over check MTU 1010 and all the crosses registered significant positive standard heterosis except BPT 5204 x NLR 145 cross. Heterobeltiosis in both positive and negative directions were observed earlier also, in studies of Yadav et al. (2004), Borah and Barman et al. (2010) and Gouri Shankar et al. (2010). This indicates both increasing and decreasing alleles are dominant depending on the parents involved Panicle weight Heterosis for this trait was high as evident from fourteen hybrids showing heterosis in significant positive direction for this trait from (Akshyadhan x NLR 145) to per cent (BPT 5204 x Pusa 1121) and only five hybrids showed heterosis in significant negative direction (Table 4.4). Heterobeltiosis was observed in both the directions for this character indicating that dominant genes have both increasing and decreasing effects. Seven crosses were significantly superior to their respective better parents, while twelve crosses expressed significantly negative heterobeltiosis. The crosses viz., BPT 5204 x Pusa 1121(37.35), RNR 2354 x Improved Pusa Basmati (35.27), BPT 5204 x Akshyadhan (35.07), Improved Pusa Basmati x Basmati 370 (29.36), Sumathi x Improved Pusa Basmati (28.38), BPT 5204 x Sumathi (17.93) and NLR 145 x Sumathi (11.58) expressed significant positive heterobeltiosis. The standard heterosis over MTU 1010 ranged from

113 (Pusa 1121 x Improved Pusa Basmati) to (BPT 5204 x Akshyadhan) per cent Number of filled grains per panicle The magnitude and direction over mid parent varied from (NLR 145 x Pusa 1121) to per cent (Pusa 1121 x Sumathi) with twenty hybrids expressing significant positive heterosis for number of filled grains per panicle (Table 4.4). This indicated that, magnitude of heterosis was high for this trait with corresponding influence on grain yield. The heterosis over better parent and standard check ranged from to per cent and from to per cent respectively. Significant and positive heterosis was recorded in ten and fifteen crosses over better parent and standard check respectively. The hybrid Pusa 1121 x Sumathi recorded highest positive and significant heterosis over both better parent ( %) and standard check ( %), whereas the cross NLR 145 x Pusa 1121 registered lowest significant heterosis over both better parent ( %) and standard check ( %). Heterosis over mid parent was reported by Aananthi and Jebaraj (2006), Deoraj et al. (2007) and Tiwari et al. (2011) whereas higher amount of heterobeltiosis for filled grains per panicle was observed by Annadurai and Nandarajan (2001), Singh et al. (2006b), Deoraj et al. (2007), Narasimman et al. (2007) and Singh et al. (2007) grain weight The spectrum of mid parental heterosis was from (Pusa 1121 x Improved Pusa Basmati) to (NLR 145 x Pusa 1121) per cent and among the hybrids tested, 21 hybrids expressed significant positive heterosis for 1000 grain weight. For heterobeltiosis the values ranged from (Pusa 1121 x Improved Pusa Basmati) to per cent (NLR 145 x Improved Pusa Basmati). Fifteen crosses exhibited significant negative heterobeltiosis and ten crosses registered significant positive heterosis over better parent. The crosses Pusa 1121 x Improved Pusa Basmati and BPT 5204 x Basmati 370 recorded highest negative significant heterosis over both mid and better parents (Table 4.5). With regard to standard heterosis, nine crosses showed significant and positive standard heterosis over the check MTU 1010 and 4 crosses over the check Pusa The crosses Akshyadhan x Pusa 1121 and BPT 5204 x RNR 2354 expressed maximum positive and negative standard heterosis respectively over the check MTU 1010.

114 Vanaja and Babu (2004), Verma et al. (2004), Sarial et al (2006) and Deoraj et al. (2007) in their studies observed positive and negative heterosis and heterobeltiosis for 1000 grain weight Grain yield per plant The range of heterosis over mid parent ranged from (NLR 145 x Pusa 1121) to per cent (BPT 5204 x Pusa 1121) and over better parent it varied between (Pusa 1121 x Sumathi) and per cent (BPT 5204 x Pusa 1121). Nineteen crosses exhibited significant positive heterosis over mid parent and eleven over better parents. The cross BPT 5204 x Pusa 1121 recorded highest positive significant heterosis over better parent (97.92 %) followed by BPT 5204 x Akshyadhan (49.65 %), RNR 2354 x Improved Pusa Basmati (43.24 %) and Sumathi x Improved Pusa Basmati (34.03 %) respectively (Table 4.5). Very high amount of heterosis was reported in the recent times for grain yield by Tiwari et al. (2011) and Gnanamalar and Vivekanandan (2013) in accordance with the present findings. The range of standard heterosis varied from to per cent over the yield check MTU Highest positive heterosis was recorded in the cross, BPT 5204 x Akshyadhan (74.93 %) followed by BPT 5204 x Pusa 1121 (34.60 %), Akshyadhan x Sumathi (26.29 %) and Improved Pusa Basmati x Basmati 370 (23.08 %), whereas, highest negative heterosis was noticed in the cross, NLR 145 x Pusa 1121 ( %) followed by Pusa 1121 x Improved Pusa Basmati ( %), Pusa 1121 x Sumathi ( %) and RNR 2354 x Sumathi ( %) Kernel length For the character kernel length, the relative heterosis was in the range of (Sumathi x Basmati 370) to per cent (BPT 5204 x Sumathi). Nine crosses recorded significant negative mid parental heterosis, whereas 14 crosses registered significant and positive heterosis over the mid parent. Top five crosses with highest mid parental heterosis were BPT 5204 x Sumathi (21.32 %), Pusa 1121 x Sumathi (17.02 %), Akshyadhan x Improved Pusa Basmati (15.40 %), Akshyadhan x RNR 2354 (13.07 %) and Akshyadhan x NLR 145 (11.05 %). The magnitude of heterobeltiosis ranged from (BPT 5204 x Pusa 1121) to per cent (Pusa 1121 x Sumathi) with 17 crosses showing significant and negative heterobeltiosis and only five crosses with significant positive values for this

115 trait. The study indicated that, the level of heterosis for kernel length is low and expression of superiority was mostly under governance of additive genetic variation. For standard heterosis, the range varied from (BPT 5204 x RNR 2354) to per cent (Pusa 1121 x Sumathi). All the crosses exhibited significant negative standard heterosis over the check Pusa 1121 except the cross Pusa 1121 x Sumathi. Under this situation, selecting for short grained aromatic genotypes suiting the local demand would be an easy task. The magnitude of heterosis realized for this trait indicated presence of quantum of variability for this trait to obtain segregants with desirable kernel lengths. Researchers like Reddy et al. (1991), Sreedhar et al. (1999), Singh (2005), Krishna Veni et al. (2005), Shivani et al. (2009) and Kumar Babu et al. (2010) also obtained similar results previously Kernel breadth Lesser dimensions of kernel breadth (mm) are always desirable, since slenderness enhances the length/breadth ratio and kernel length after cooking and fetch high premium in market. In contrast, bold kernels with higher breadth are often discriminated against because they break in milling (Jennings et al. 1979). Thus, heterosis in negative direction is desirable for this trait accordingly significant negative heterosis was recorded in thirteen hybrids with a rage of percent in (Sumathi x Basmati 370) to per cent in (NLR 145 x Basmati 370). Similarly, five hybrids registered significantly negative heterobeltiosis and the range was from percent in (RNR 2354 x Basmati 370) to percent (NLR 145 x Basmati 370). Fourteen hybrids recorded significantly negative standard heterosis over the check Pusa 1121 from (Pusa 1121 x RNR 2354) to per cent (BPT 5204 x RNR 2354). Negative heterosis for kernel breadth was also reported by Singh and Singh (1985) and Mandal and Sunil Saran (1989), Vivekanandan and Giridharan (1994), Sreedhar et al. (1999), Krishna Veni et al. (2005) and Kumar Babu et al. (2010) in correlation with present outcome of the investigation Kernel L/B ratio The relative heterosis ranged from (Sumathi x Improved Pusa Basmati) to per cent (NLR 145 x Basmati 370) for this trait. It was significant and positive in 13 crosses, while significant and negative in six crosses. NLR 145 x Basmati 370 recorded highest significant positive value of per cent followed by BPT 5204 x Basmati 370 (18.92 %) and Akshyadhan x Improved Pusa Basmati (14.54 %).

116 Heterobeltiosis in both the directions was almost equal and the extent for this trait was between (BPT 5204 x Pusa 1121) and per cent (Pusa 1121 x Sumathi). Six hybrids recorded significant and positive heterobeltiosis and seventeen crosses recorded significant and negative heterobeltiosis (Table 4.6). Crosses with lesser L/B ratios indicated the possibility of obtaining segregants with short slender grains with aroma. However, Standard heterosis over the check Pusa 1121was significantly negative in all crosses except Pusa 1121 x Sumathi and Akshyadhan x Improved Pusa Basmati. The cross Pusa 1121 x Sumathi registered highest positive and significant heterosis over both better parent and standard check. Earlier researchers viz., Reddy et al. (1991), Geetha and Ayyamperumal (1997), Sreedhar et al. (1999), Singh (2005), Krishna Veni et al. (2005) and Kumar Babu et al. (2010) reported positive heterosis for Length/Breadth ratio and Chauhan and Chauhan (1995), Raju et al. (2003) and Saravanan et al. (2006) for negative heterosis Kernel length after cooking Lengthwise expansion of kernel after cooking is a highly desirable feature and manifestation of heterosis for this trait is useful. Sixteen crosses had shown heterosis to kernel length after cooking in desirable direction and maximum percentage of was associated with Akshyadhan x NLR 145 and minimum was observed in Pusa 1121 X Basmati 370 (5.83 per cent). Nine crosses had significant heterosis in negative direction. Twelve crosses recorded significant positive heterobeltiosis with a range of 4.72 to per cent and thirteen crosses shown significant heterobeltiosis in negative direction with a magnitude of to per cent. The cross, Akshyadhan x NLR 145 recorded significant positive heterosis over better parent (Table 4.6). For standard heterosis, the range varied from (BPT 5204 x Akshyadhan) to per cent (Akshyadhan x Basmati 370). Fourteen hybrids exhibited significantly positive heterosis over Pusa 1121, while six crosses recorded significant and negative values for standard heterosis Kernel elongation ratio Lengthwise expansion of kernel after cooking is a highly desirable quality trait as such manifestation of heterosis for this trait is most essential. Among the hybrids studied, twelve hybrids were significantly superior over the mid parental value with a range from 7.51 (Sumathi x Improved Pusa Basmati) to per cent (Sumathi x

117 Basmati 370) and seven hybrids recorded significant positive heterobeltiosis with a minimum of 9.91 in BPT 5204 x NLR 145 to a maximum of per cent in and Sumathi x Basmati 370, while, thirteen crosses expressed significant negative heterosis over better parent. Standard heterosis ranged from to per cent over the best check Pusa The best cross was BPT 5204 x RNR 2354 which registered significant and positive standard heterosis (Table 4.7). Sahai et al. (1986), Tomar (1987), Geetha and Ayyamperumal (1997), Sreedhar et al. (1999), Singh (2005), Krishna Veni et al. (2005) and Roy et al. (2009) also reported good manifestation of heterosis for kernel length after cooking and kernel elongation ratio, in several combinations emphasizing usage of both additive and non-additive types of genetic variation Head rice recovery The heterosis ranged from (BPT 5204 x Improved Pusa Basmati) to 8.30 per cent (BPT 5204 x NLR 145) over mid value and from (BPT 5204 x RNR 2354) to 4.13 per cent (RNR 2354 x Sumathi) over better parent. Only three hybrids viz., BPT 5204 x NLR 145, NLR 145 x Sumathi and Pusa 1121 x RNR 2354 over mid parent exhibited significant positive heterosis, while none of the crosses recorded significantly positive values over better parent (Table 4.7). Twenty three crosses registered significantly positive heterosis over the check Pusa 1121, while three crosses recorded significantly negative values. BPT 5204 x NLR 145 (51.50 %) recorded highest value of standard heterosis followed by Akshyadhan x NLR 145 (42.50 %), NLR 145 x Sumathi (37.90 %) and BPT 5204 x Akshyadhan (37.38 %). The hybrid BPT 5204 x NLR 145 recorded highest positive and significant heterosis over both mid parent (8.30 per cent) and standard check (51.50 per cent). Sahai et al. (1986), Mandal and Sunil Saran (1989), Sreedhar et al. (1999), Singh (2005), Singh and Lal (2005), and Shivani et al. (2009) also reported heterosis for head rice recovery at varying levels depending on parents involved.

118 4.2.2 INBREEDING DEPRESSION Inbreeding depression refers to the reduction in population mean from the preceding (parent) population mean after selfing. Its converse is heterosis, the hybrid vigor manifested as increased size, growth rate or other parameters resulting from the increase in heterozygosity in F 1 generation from crosses made between pure lines. Inbreeding depression, the depressive effect, is the expression of traits arising from increasing homozygosity (Allard, 1960). In quantitative genetics theory, inbreeding depression and heterosis are due to non-additive gene action, and are considered to be two aspects of the same phenomenon (Mather and Jinks, 1982). Li et al. (1997) suggested that hybrid breakdown in rice was part of inbreeding depression largely related to additive epistasis. The positive estimates of depression indicate the decrease in the population mean when the dominant genes are plus genes. In contrast, when the dominant genes are minus genes, there will be less expression of F 1 s especially when the directional dominance is on negative side and consequently when selfed, the F 2 s performance increases due to segregation and fixation of alleles and decrease in negative dominance effect and heterozygosity. Thus negative heterosis followed by the negative estimates of inbreeding depression indicates the presence of non additive gene effects. For certain characters like days to flowering and plant height, heterosis in negative direction will be advantageous when the breeding objective is aimed at evolving early and short stature plant types. In the present investigation, heterosis and inbreeding depression were studied to understand the type of gene action (additive or non additive) and to finally identify better crosses for pedigree selection or hybrid development Days to 50 per cent flowering In case of days 50 per cent flowering, very high amount of heterosis was realized in desirable negative direction on better parent and these heterotic effects were mainly due to non additive gene action, as there was high increase in F 2 generation mean. The findings of Ganesan et al. (1997) and Nuruzzaman et al. (2002) were in similar lines with high negative heterosis followed by a substantial increase in F 2 generation for days to panicle emergence and they concluded that non-additive gene effects played an important role in its inheritance. Two promising crosses viz., BPT 5204 x Akshyadhan and BPT 5204 x Sumathi which exhibited significant negative

119 heterobeltiosis with no inbreeding depression could be better capitalized through simple selection. On the whole, high heterosis in negative direction was associated with high per se performance in F 2 generation as such selection is many crosses might not be of much fruitful Plant height For this trait, most of the crosses exhibited heterosis in undesirable positive direction. The cross combinations viz., Pusa 1121 x Sumathi (ID: , H1: and H2: per cent) and Pusa 1121 x Basmati 370 (-16.14, and per cent) exhibited negatively significant heterosis but increase in mean performance of F 2 indicated a predominant role of non additive gene effects (Table 4.3). These results were in conformity with the earlier results of Ganesan et al. (1997). Instead of direct selection for dwarfness, intermating in F 2 generation and then selection might be a fruitful attempt Number of productive tillers/plant The magnitude of heterosis was very low for this trait, as most of the crosses showed negative heterobeltiosis due to poor performance of F 1 s. The corresponding inbreeding depression was also low as there was substantial increase in F 2 generation. Highest values of heterobeltiosis followed by low inbreeding depression were recorded in case of NLR 145 x Basmati 370 (H2: 20.52, ID: per cent) and Improved Pusa Basmati x Basmati 370 (10.99, ). The other promising crosses viz., BPT 5204 x NLR 145 and BPT 5204 x Improved Pusa Basmati which manifested highest levels of heterosis on mid parent coupled with less inbreeding depression, were the best crosses for improvement of tillering ability through selection (Table 4.3). Such crosses may through pure lines on account of prevalence of additive gene actions. The cross, Akshyadhan x Improved Pusa Basmati with significant heterosis accompanied by high inbreeding depression indicted mainly the preponderance of nonadditive gene action as such, could be exploited through hybrid breeding or recurrent selection (Reddy and Nerkar, 1995 and Reddy, 1996) Panicle length For the trait, the cross combinations which exhibited highly significant heterosis also had inbreeding depression, with few exceptions. The cross, BPT 5204 x Pusa 1121, NLR 145 x Pusa 1121 and Pusa 1121 x RNR 2354 which recorded no inbreeding depression coupled with highly significant positive heterosis were treated as useful

120 crosses (Table 4.4). The crosses viz., RNR 2354 x Sumathi, Sumathi x Improved Pusa Basmati and Akshyadhan x Improved Pusa Basmati showed highly significant heterosis, but there was poor expression in F 2 generation due to sever inbreeding depression. Patil et al. (2003), Datt and Mani (2004) and Pandy and Tripathi (2006) also reported earlier similar results and recommended simple selection for improvement of panicle length in certain crosses and in few crosses, where high inbreeding depression was high, recommended for population improvement procedures Panicle weight The significant inbreeding depression was exhibited by 13 crosses with a ranging from (Akshyadhan x Basmati 370) to the maximum value of (RNR 2354 x Sumathi) for the character Panicle weight. Among the crosses tested, high estimates of inbreeding depression in F 2 with high heterobeltiosis in F 1 were recorded in case of BPT 5204 x Pusa 1121(H2: 37.35, ID: per cent), Improved Pusa Basmati x Basmati 370 (29.36, 35.26), BPT 5204 x Akshyadhan (35.07, 38.44), RNR 2354 x Improved Pusa Basmati (35.27, 27.49) and Sumathi x Improved Pusa Basmati (28.38, 31.42) which indicated the presence of mostly non-additive gene action and similarly the crosses viz., Pusa 1121 x Sumathi (-47.79, ), NLR 145 x Pusa 1121 (-37.99, ) and BPT 5204 x NLR 145 (-13.13, ) exhibited high estimates of heterobeltiosis in negative side with no inbreeding depression due to increased performance of F 2, may also be considered for selection. The cross BPT 5204 x Sumathi showed low inbreeding depression (16.82) with significant heterobeltiosis and good per se performance was also a good cross combination in addition to those discussed above Number of filled grains Among the characters under study grains per panicle seemed to be largely under influence of non additive type of gene action, as evident from high heterosis accompanied by high inbreeding depression. For this trait, all the crosses exhibited significant inbreeding depression except the cross, NLR 145 x Pusa 1121 (-91.14). Inbreeding depression ranged from 9.86 (BPT 5204 x NLR 145) to (RNR 2354 x Sumathi) (Table 4.4). The crosses viz., Pusa 1121 x Sumathi (H1: , H2: ), Pusa 1121 x Improved Pusa Basmati (132.58, ), RNR 2354 x Improved Pusa Basmati (113.67, 48.91) and Sumathi x Improved Pusa Basmati (91.22, 28.20) exhibited superior performance over mid and better parents showed inbreeding

121 depression in F 2 to the extent of 82.66, 50.58, and per cent respectively which indicated that breeding methods which involves direct selection would not be much fetching (Raju et al. 2005). The cross NLR 145 x Pusa 1121 which recorded heterosis and heterobeltiosis in negative direction had not shown any inbreeding depression in F 2 generation. The genes with dominance effects towards negative side may exhibit negative heterosis in F 1 but may show increased performance in F 2 due to fixation of genes in such cases, selection of plants with more grains per panicle especially in case of two crosses, NLR 145 x RNR 2354 (ID: 19.92) and BPT 5204 x RNR 2354 (ID: 21.10) showing less inbreeding depression, higher magnitude of residual heterosis would be indeed more rewarding. Among the crosses studied NLR 145 x RNR 2354 (ID: 20.01) and BPT 5204 x RNR 2354 (ID: 21.10), which showed minimum inbreeding depression with significant heterosis over both mid and better parents may be due to dispersion of genes in parents, were considered suitable for single plant selection and further advancement grain weight In comparison to other traits, inbreeding depression was very low for 1000 grain weight i.e. from 0.02 (BPT 5204 x Sumathi) to 2.33 (Pusa 1121 x RNR 2354). Highest values of heterobeltiosis with minimum inbreeding depression was recorded in case of NLR 145 x Improved Pusa Basmati (H1:22.98, H2: 21.01, ID: 0.22 per cent), Akshyadhan x Pusa 1121 (16.24, 11.58, -0.22), NLR 145 x Sumathi (18.22, 7.57, 0.9) and Sumathi x Improved Pusa Basmati (14.87, 0.68, 0.19) (Table 4.5). These crosses with less inbreeding depression could be better utilized for development of true breeding lines with higher test weight as fixable additive genetic effects were involved in the inheritance. These results are in agreement with the findings of Ranganathan et al. (1973), Pandey et al. (1995) and Datt and Mani (2004). The cross which recorded significant heterobeltiosis in negative direction had shown improved performance in F 2 especially in case of RNR 2354 x Sumathi (-3.06), Pusa 1121 x Basmati 370 (-2.66) and BPT 5204 x Basmati 370 (-1.39) as such these crosses were also considered as useful for pedigree selection to develop higher test weight genotypes.

122 Grain yield For grain yield per plant, the crosses with significant positive heterosis and heterobeltiosis also exhibited high percentage of inbreeding depression subsequently. Inbreeding depression ranged from 6.72 (NLR 145 x RNR 2354) to per cent (RNR 2354 x Sumathi). In certain crosses, there was an increase in F 2 mean, because of poor expression of heterosis due to negative dominant gene effects in F 1 s and the estimates were in negative side from (BPT 5204 x Improved Pusa Basmati) to (NLR 145 x Pusa 1121) per cent for grain yield (Table 4.5). In case of BPT 5204 x Pusa 1121, BPT 5204 x Akshyadhan, RNR 2354 x Improved Pusa Basmati, Sumathi x Improved Pusa Basmati and Pusa Basmati x Basmati 370, higher magnitude of heterosis (130.52, 89.21, 85.65, and per cent) and heterobeltiosis (97.92, 49.65, 43.24, and per cent) accompanied by high inbreeding depression (42.35, 48.33, 36.88, and 53.42) was due to prevalence of non-additive gene action (Ram, 1992, Reddy and Nerkar, 1995 and Raju et al., 2005). Significant positive heterosis with low inbreeding depression was also observed in few crosses viz., NLR 145 x RNR 2354 (H 1 :18.86, ID: 6.72) and Akshyadhan x RNR 2354 (H 1 : 20.79, ID: 7.61), such crosses, can be used for selection of pure lines with high yield Kernel length The magnitude of inbreeding depression was between (Sumathi x Basmati 370) and (Pusa 1121 x Sumathi) with 17 crosses registering at significant level for kernel length. Three crosses viz., Pusa 1121 x Sumathi (H1: 17.02, H2: per cent), Akshyadhan x RNR 2354 (13.07, 10.68) and Akshyadhan x Improved Pusa Basmati (15.40, 3.66) which exhibited superior performance over their mid and better parents showed inbreeding depression to the extent of 22.72, and per cent respectively. Higher values of heterobeltiosis in negative direction were associated with most of crosses. Except one, all the crosses showed negative heterosis on standard check (Pusa 1121) also. The cross, Pusa 1121 x Sumathi which had expressed heterosis and standard heterosis had also shown inbreeding depression Kernel breadth For grain breadth negative heterosis is desirable to evolve quality rice. Only four crosses expressed heterosis on negative side with no inbreeding depression as such selection for slender grains in such crosses (NLR 145 x RNR 2354,

123 NLR 145 x Basmati 370, Pusa 1121 x Basmati 370 and RNR 2354 x Basmati 370) would be highly rewarding (Table 4.6). The crosses with significant negative values of heterosis and heterobeltiosis exhibited higher per se of F 2 generation indicating the presence of non-additive gene action (dominance and epistasis) for grain breadth Kernel L/B ratio For kernel L/B ratio, significant inbreeding depression was exhibited by seven crosses with a minimum of 4.00 (Akshyadhan x Pusa 1121) to the maximum of (BPT 5204 x Basmati 370). Six crosses manifested heterosis over better parent and the cross NLR 145 x RNR 2354 with no inbreeding depression was identified for further advancement to develop true breeding lines with high kernel L/B ratio (Table 4.6). Chauhan and Chauhan (1995), Verma et al. (2002), Janardhan et al. (2001a) and Sanjeev kumar et al. (2007b) also reported low levels of heterosis and inbreeding depression for kernel shape. Reddy et al. (1991) also reported lower magnitude of heterosis for kernel length and kernel L/B ratio suggesting none of F 1 s was superior in grain fitness to their parental lines Kernel length after cooking In most of the crosses significant inbreeding depression existed for kernel length after cooking, 3 crosses, Akshyadhan x NLR 145 (39.36, 34.53), Sumathi x Basmati 370 (32.69, 29.13) and BPT 5204 x RNR 2354 (25.26, 26.89) with high heterobeltiosis had maximum inbreeding depression (Table 4.6). Significant values of negative heterobeltiosis with increased F 2 mean in case of BPT 5204 x Pusa 1121 (-17.65, ), BPT 5204 x Akshyadhan (-13.64, ) and NLR 145 x Pusa 1121 (-17.65, ) suggested presence of non additive gene effects. Among the total crosses studied, Akshyadhan x Pusa 1121 (ID: 6.52) and Pusa 1121 x RNR 2354 (ID: 8.24) showed minimum level of inbreeding depression with significant positive heterosis over mid parent in F 1 generation Kernel elongation ratio Negative heterosis and low inbreeding depression were observed in most of the crosses for kernel elongation ratio (Table 4.7). The crosses viz., Sumathi x Basmati 370 (40.82, 40.52, 32.21), BPT 5204 x RNR 2354 (38.37, 31.89, 28.83) and NLR 145 x RNR 2354 (13.80, 13.69, 19.90) with high amount of heterobeltiosis showed maximum inbreeding depression. In the present study, only one cross (Akshyadhan x NLR 145) showed highly significant heterosis and heterobeltiosis with least inbreeding depression

124 suggesting that additive gene action played key role for kernel elongation ratio in this particular cross Head rice recovery For whole grain yield, three cross combinations viz., BPT 5204 x NLR 145, NLR 145 x Sumathi and Pusa 1121 x RNR 2354 recorded significant inbreeding in F 2 generation depression with higher expression of heterosis over mid parent in F 1 generation (Table 4.7). The crosses viz., Sumathi x Improved Pusa Basmati (-31.54, , 0.00), Improved Pusa Basmati x Basmati 370 (-26.70, , 8.71) and Akshyadhan x Basmati 370 (-23.82, , 16.34) showed least inbreeding depression as heterobeltiosis was negative in F 1 generation. Heterosis and inbreeding depression studies revealed presence of significant heterosis over mid and better parents in many cross combinations. The crosses BPT 5204 x Pusa 1121 (panicle length and panicle weight), BPT 5204 x Akshyadhan (number of productive tillers/plant and panicle weight) and RNR 2354 x Improved Pusa Basmati (panicle weight, number of filled grains/panicle and 1000 grain weight) exhibited highly significant heterosis and heterobeltiosis for yield and its important component characters besides earliness. The other crosses viz., RNR 2354 x Improved Pusa Basmati, Sumathi x Improved Pusa Basmati and Akshyadhan x Improved Pusa Basmati exhibited significant heterosis for yield and yield contributing characters in addition to important grain quality traits like kernel length and L/B ratio. Significant heterosis coupled with low inbreeding depression was observed in one cross viz., Akshyadhan x Pusa 1121, as such, this particular cross could be made use for development of high yielding pure lines with aroma. High heterosis in F 1 generation was accompanied by high inbreeding depression in F 2 generation for the prime yield component, filed grains per panicle, whereas, at the same time, the inbreeding depression was low for panicle weight and 1000 grain weight. Hence, direct selection for yield improvement through these two characters would be highly beneficial. In similar lines, BPT 5204 x RNR 2354 and Akshyadhan x Basmati 370 were identified as best crosses for development of pure lines with good cooking qualities.

125 4.3 COMBINING ABILITY ANALYSIS The performance of parents in hybrid combinations can be tested by combining ability analysis which also characterizes the nature and magnitude of gene action involved in the expression of quantitative traits. The main objective of this study is to identify parents with better potential to transmit desirable characters to their progeny and to identify the better specific crosses for quality, yield and yield components. The analysis of quantitative inheritance is also equally important to generate knowledge on the nature and magnitude of gene action and to choose most appropriate and efficient breeding procedure for crop improvement. Information regarding nature of gene action may be helpful in the development of efficient breeding programme. General combining ability is attributed to additive and additive x additive gene action which is fixable in nature. On the other hand, specific combining ability is attributed to non additive gene action which may be due to dominance or epistasis or both and is non-fixable in nature but is the primary justification for initiating the hybrid breeding programme (Cockerham, 1961). Combining ability analysis was therefore carried out in the present investigation to obtain information on gca effects of parents and sca effects of crosses which would help in selection of better parents and cross combinations for their further use in breeding programme for the improvement of the yield and related traits Analysis of variance Analysis of variance for combining ability revealed significant differences within parents, crosses (F 1 s) and parents vs. hybrids for all the 14 characters studied (Table 4.8). Analysis of variance for combining ability for quality, yield and yield components (Table 4.9) indicated that general combining ability (GCA) and specific combining ability (SCA) mean squares were highly significant for all the characters. This indicated both additive and non additive gene actions were involved in controlling the characters under the present investigation. Information on top ranking cross combinations for various characters is presented in Table Analysis of variance and components of variance The aim of a breeder of self-pollinated crop like rice would mostly be to develop true breeding (homozygous) lines with various desirable characteristics contributing to the yield and quality. According to Griffing (1956), the combining ability analysis

126 partitions the genotypic variability into two variances i.e due to general combining ability (GCA) and specific combining ability (SCA), which represents the additive effects and deviation from additive respectively for the controlling of various quantitative traits in parents and their hybrids. The estimates of general combining ability (GCA) and specific combining ability (SCA) variances, their ratios and gene action are presented in Table The analyses of variance showed that, the variances due to SCA were higher than those due to GCA for 12 characters viz., days to 50 per cent flowering, plant height, number of productive tillers per plant, panicle weight per plant, number of filled grains per panicle, grain yield per plant, kernel length, kernel breadth, kernel L/B ratio, kernel length after cooking, kernel elongation ratio and head rice recovery whereas, for panicle length and 1000 grain weight, GCA variances were higher than SCA variances (Table 4.9). The finding of the present study revealed that the non-additive gene action played greater role than additive gene action for all the traits except panicle length and 1000 grain weight as reported earlier by Vanaja et al. (2003); Pradhan et al. (2006); Ramakrishan et al. (2006). However, few researchers have reported predominantly nonadditive gene action for yield and yield attributes (Allahgholipour and Ali, 2006) Estimation of general and specific combing ability effects Combining ability is the ability of a parent to produce superior progeny with other lines which helps the plant breeder in the selection of desirable parents that can be utilized for effective breeding programme. General combining ability (gca) effects are the average performance of a parent in a series of crosses with other parents, whereas specific combining ability (sca) effects are the deviations in the performance from expected gca effects of each parent. The gca effects reflect performance of parental lines in combination with all other lines, so parents with highest gca effects are useful for the trait improvement while specific combining ability effects would help identify the best hybrid combinations. The combining ability effects were estimated for all the characters as they had significant contribution to total variance. The effects due to general combining ability and specific combining ability are presented under following heads.

127 GENERAL COMBINING ABILITY EFFECTS The estimates of general combing ability effects pertaining to eight parents for different characters are presented character wise below (Table 4.10) Days to 50% flowering The parents Pusa 1121 (-7.84), Sumathi (-2.51), Basmati 370 (-1.71) and Akshyadhan (-0.54) have recorded significant negative gca effects for this trait and considered to be the good combiners conferring earliness to the hybrids, while BPT 5204 (5.93), NLR 145 (5.59) and Improved Pusa Basmati (0.66) exhibited significant positive effects and were considered as poor general combiners for earliness Plant height For the character plant height, gca effects in negative side is more desirable to develop non lodging and semi dwarf genotypes in rice. Accordingly the parents, BPT 5204 (-8.57), Improved Pusa Basmati (-3.01), NLR 145 (-2.13), RNR 2354 (-1.76) and Basmati 370 (-1.69) recorded significantly negative gca effects and the parents Akshyadhan and Sumathi recorded significant positive gca effects for this trait Number of productive tillers/plant The parents Pusa 1121 (0.82) and BPT 5204 (0.74) expressed significant positive gca effects for tillering ability, which indicated that these parents are good general combiners for this trait, while the parents RNR 2354, Improved Pusa Basmati, Sumathi and Basmati 370 were found to be the poor combiners Panicle length Genotypes with long panicles are highly useful, as they will have good filling and more grains per panicle. Akshyadhan (2.29), Sumathi (1.55), Improved Pusa Basmati (1.31) and Basmati 370 (0.89) exhibited positive and significant gca effects and these parent were recognized as good general combiners for increasing panicle length, whereas BPT 5204, NLR 145 and RNR 2354 were poor combiners Panicle weight The gca effects were found to be significant and positive in case of Akshyadhan and BPT 5204, whereas they were negative in case of Sumathi, Pusa 1121, Basmati 370 and Improved Pusa Basmati.

128 Number of filled grains/panicle Generally high per se performance is associated with high gca effects such phenomenon was exhibited by Akshyadhan, RNR 2354 and Sumathi. The parents NLR 145, Pusa 1121 and Improved Pusa Basmati exhibited very poor undesirable gca effects for this character. In the present study the parent, Akshyadhan alone had significant gca effect in positive direction for panicle length in addition to filled grains per panicle and panicle weight, thus, identified as good general combiner for improving panicle traits grain weight In addition to effective tillers, grains per panicle, 1000 grain weight is considered as major yield component, as genotypes with long and bold grains exhibit higher yield potentiality. The parents Akshyadhan, Pusa 1121, Sumathi and NLR 145 were registered as good combiners for 1000 grain weight, because of their highly significant gca effects for this important yield component while rest of the parents, BPT 5204, RNR 2354, Improved Pusa Basmati and Basmati 370 were very poor in their combining ability for test weight Grain yield per plant Though grain yield is the cumulative effect of individual components, it is a measure to assess the combining efficiency of so many individual factors involved in its final expression. Significant gca effects in the desirable direction were registered in case of Akshyadhan (5.85), Basmati 370 (2.21), BPT 5204 (1.75) and Sumathi (1.28) for grain yield per plant. The parents Pusa 1121, NLR 145, Improved Pusa Basmati and RNR 2354 exhibited significant negative gca effects for yielding ability Kernel length For this character, Pusa 1121, Sumathi, Improved Pusa Basmati and Basmati 370 were identified as good combiners, because of highly significant positive gca effects and the remaining parents had poor combining ability Kernel breadth Negative gca effects are desirable for this quality trait and as per this criteria only Improved Pusa Basmati and BPT 5204 were recorded as good general combiners. Three parents, Pusa 1121, Akshyadhan and NLR 145 exhibited significant and positive gca effects.

129 Kernel L/B ratio Among all the parents, significant and positive gca effects were observed for Pusa 1121 followed by Sumathi, Improved Pusa Basmati and Basmati 370. Hence, these parents were identified as good general combiners for incorporation of fine grain quality in progenies. The other parents, viz., BPT 5204, RNR 2354, NLR 145 and Akshyadhan recorded significant and negative gca effects Kernel length after cooking Kernel length after cooking is an important quality parameter because in some cases even longer kernels show very less elongation. Improved Pusa Basmati, Basmati 370 and Sumathi exhibited significant positive gca effects and among these, Improved Pusa Basmati was highly superior. Other parents viz., BPT 5204, NLR 145 and Pusa 1121 were poor combiners Kernel elongation ratio Among the parents, RNR 2354, Improved Pusa Basmati and Basmati 370 registered higher magnitudes of gca effects in desirable side, whereas Pusa 1121 and Sumathi exhibited significant negative gca effects Head rice recovery Both positive and negative significant gca effects were observed for this trait. Akshyadhan and NLR 145 were registered as good general combiners, in view of their significant positive gca effects. Three parents, viz., Pusa 1121, RNR 2354 and Improved Pusa Basmati had significant negative gca effects for head rice recovery. It can be concluded that, genotypes with high per se for yield also possessed high gca for relevant yield characters. Among the parents, Akshyadhan, Basmati 370 and Sumathi were proved to be good combiners for grain yield as well as its prime component traits like panicle length, panicle weight, filled grains per panicle and 1000 grain weight (Table 4.12 & 4.13). Whereas, Improved Pusa Basmati and Basmati 370 combined well for kernel characters including cooking quality traits (kernel length, kernel breadth, kernel length/breadth ratio, kernel length after cooking and kernel elongation ratio) which otherwise were poor combiners for yield. Chawla and Gupta (1982) stated that, parents with high mean performance as well as high gca effects are likely to produce transgressive segregants in the F 2 generation as well as in later generations. As such the parents, Akshyadhan, Basmati 370 for improving grain yield

130 and Improved Pusa Basmati and Basmati 370 for improving quality were given the best option for breeding material generation SPECIFIC COMBINING ABILITY EFFECTS Specific combining ability effects with respect 28 F 1 hybrids were estimated for yield and quality characters and presented (Table 4.11). For days to 50% flowering, plant height and kernel breadth, the crosses with negative sca effects were treated as desirable, whereas for remaining traits crosses with positive sca effects were considered as useful Days to 50% flowering When the breeding programme is designed for earliness, the crosses with negative sca would be considered for further improvement. The specific combining ability effects were ranged from (Pusa 1121 x Sumathi) to 4.83 (BPT 5204 x NLR 145). Out of twenty eight hybrids, eighteen hybrids exhibited significant negative sca effects and two hybrids exhibited significant and positive sca effects. The crosses, Pusa 1121 x Sumathi (-10.47), NLR 145 x Improved Pusa Basmati (-8.07), Pusa 1121 x Improved Pusa Basmati (-6.31), Akshyadhan x NLR 145 (-5.87), Akshyadhan x RNR 2354 (-5.37) and RNR 2354 x Improved Pusa Basmati (5.24) recorded significant negative sca effects with very higher values in desirable direction involving the parents with high x high, low x medium, high x medium, high x low and medium x medium gca effects. As non-additive gene action played a significant role, inter-mating the selected individuals in early generation and followed by selection would help in developing early maturing genotypes (Rahimi et al. 2010, Saidaiah et al. 2010, Padmavathi et al and Roy et al. 2012) Plant height Six crosses exhibited significant negative sca effects from (Akshyadhan x NLR 145) to (Pusa 1121 x Sumathi). The crosses, Pusa 1121 x Basmati 370 (-21.31), RNR 2354 x Sumathi (-11.06) and Pusa 1121 x Basmati 370 (-7.94) registered high sca estimates in desired direction with the parents possessing average x high, high x low and average x high gca effects, which indicated the presence of non-additive gene effects (Rahimi et al. 2010, Saidaiah et al and Padmavathi et al. 2012).

131 Number of productive tillers per plant Number of productive tillers is an important yield component in rice. The sca effects among 28 hybrids were from (Pusa 1121 x Improved Pusa Basmati) to 1.85 (NLR 145 x Basmati 370) with fifty per cent of crosses exhibiting positive sca effects. Among the crosses with positive effects, nine were found to be highly promising with high sca and per se. The highest positive sca effects were shown by NLR 145 x Basmati 370 (1.85) followed by Pusa 1121 x Basmati 370 (1.60) and such sca effects were mostly due to average x low and high x low gca parents. This suggests that breeding method like population improvement rather than direct selection in these crosses would be the appropriate strategy to improve tillering capacity in rice Panicle length Out of 28 crosses, eight recorded significant positive sca effects. The highest sca effect was exhibited by BPT 5204 x Pusa 1121 (2.51) followed by Sumathi x Improved Pusa Basmati (2.42), Pusa 1121 X RNR 2354 (2.30) and RNR 2354 x Sumathi (2.28). However, significant negative sca effects were expressed by two crosses. The crosses with parents having high x high gca effects viz., Akshyadhan x Sumathi, Akshyadhan x Improved Pusa Basmati and Sumathi x Improved Pusa Basmati were considered most useful for simple selection. The remaining crosses with parents of high x low and low x low gca types, which were mostly influenced by non additive genetic effects with high genetic diversity in the form of heterozygous loci (Singh et al. 2007, Pradhan and Singh, 2008 and Saidaiah et al. 2010) could be exploited through other methods rather than direct selection Panicle weight Panicle weight is an important parameter to assess the yielding ability of rice genotypes and in general higher grain yields are associated with higher panicle weight. Out of 28 hybrids studied, nine crosses exhibited significant positive sca effects and eight crosses exhibited significant and negative sca effects. Among hybrids with significant positive effects, Akshyadhan x Pusa 1121 recorded highest value of 7.68 followed by BPT 5204 x NLR 145 (7.34) and Akshyadhan x Basmati 370 (6.26). These crosses with parents of high gca effects and high per se performance could be utilized for selection in early generations. The highest significant and negative values were recorded for Pusa 1121 x Sumathi (-8.40) followed by BPT 5204 x Akshyadhan (-15.74) and Pusa 1121 x RNR 2354 (-14.52).

132 Number of filled grains/panicle Among 3 yield components viz., number of effective tillers, grains per panicle and 1000 grain weight, number of grains per panicle is a highly variable trait depends on parent s involved and environmental conditions. In rice, more number of grains is highly associated with smaller grains and vice-versa. Hence, selection for more number with increased size would have immediate benefit on crop improvement. SCA effects were positive and significant in case of eleven crosses and among these hybrids, Pusa 1121 x Sumathi (88.8), RNR 2354 x Improved Pusa Basmati (56.38) and BPT 5204 x Akshyadhan (30.09) exhibited highest significant sca estimates with gca combinations of either high x low or medium x high in addition high heterosis. In such crosses, improvement could be possible with respect to this trait, by postponing selection in early generations and mating superior segregants so as to facilitate accumulation of favourable dominant genes. Many times, the poor combiners tend to produce crosses with high sca effects due to complementation effects and such parental combinations provide largely an environment for the full expression of the genes though the parents themselves would not express any superiority for this trait individually grain weight The range of sca effects among 28 hybrids was from (Pusa 1121 x Improved Pusa Basmati) to 3.83 (NLR 145 x Pusa 1121). Eighteen crosses exhibited positive sca effects and the remaining had negative sca effects. Among the crosses with positive sca effects, fourteen exhibited at significant level giving a good scope for the development of lines with increased test weight. The highest positive and significant sca effects were recorded in case of NLR 145 x Pusa 1121 (3.83) followed by Akshyadhan x Pusa 1121 (2.76) involving parents of high x high gca effects, which could be effectively utilized for pedigree breeding for generating pure lines with higher test weight. Selection for plants with higher test weight in early segregating generations leading to isolation of pure lines is suggested for these cross combinations due to governance of additive gene effects Grain yield per plant For grain yield, ten hybrids exhibited significant positive sca effects and among these, top five combinations were BPT 5204 x Pusa 1121 (13.24: high x low), BPT 5204 x Akshyadhan (12.16: high x high), Sumathi x Improved Pusa Basmati

133 (8.21: high x low), RNR 2354 x Improved Pusa Basmati (7.92: average x low), Improved Pusa Basmati x Basmati 370 (7.32: low x high) and NLR 145 x Sumathi (6.91: low x high). These crosses exhibited high per se and high heterosis followed by high inbreeding depression. The superior performance was mostly due to interaction of favourable and unfavorable genes and dominant effects. In such crosses, only biparental mating and selection in advance generations might be fruitful. In one cross (BPT 5204 x Akshyadhan) direct selection for high yield may be advantageous, as the superiority is supposed to be due to accumulation of most favourable dominant genes due to involvement of high x high gca parents. The cross, BPT 5204 x Pusa 1121 which recorded high sca effects for yield also exhibited significant sca effects in desired direction for other important yield contributing traits viz., panicle length, number of filled grains/panicle and 1000 grain weight like other promising crosses viz., BPT 5204 x Akshyadhan (number of productive tillers/plant and number of filled grains/panicle), Sumathi x Improved Pusa Basmati (panicle length and 1000 grain weight), RNR 2354 x Improved Pusa Basmati (panicle length, number of filled grains/panicle and 1000 grain weight) and Akshyadhan x Pusa 1121 (number of productive tillers/plant, panicle weight and 1000 grain weight) which indicated that, these promising cross combinations could be best used for yield improvement in rice by adopting appropriate breeding methods. In the present study non-additive gene effects were found to play greater role in expression of yield attributing traits, productive tillers/plant, panicle length, number of filled grains/panicle, panicle weight and ultimately the grain yield per plant. Kumar Babu et al. (2010), Jayasudha and Deepak Sharma (2010), Saidaiah et al. (2010) and Roy et al. (2012) also reported similar results with respect to yield and its component traits as in the case of recent studies Kernel length In case of kernel length, twelve cross combinations recorded positive and significant sca effects and among these, Pusa 1121 x Sumathi (1.08), BPT 5204 x Sumathi (1.06), Akshyadhan x Improved Pusa Basmati (0.70) and BPT 5204 x Basmati 370 (0.58) expressed very high sca effects. Fifteen crosses recorded significant negative sca effects ranging from (BPT 5204 x Pusa 1121) to (Sumathi x Basmati 370).

134 Kernel breadth Significant negative sca effects were recorded in eleven crosses and eight hybrids showed significant positive effects. The crosses viz., BPT 5204 x RNR 2354 (-12.61), BPT 5204 x Basmati 370 (-8.34), NLR 145 x Basmati 370 (-8.31), Pusa 1121 x Basmati 370 (-7.61), NLR 145 x Sumathi (-7.11) and RNR 2354 x Improved Pusa Basmati (-5.77) had significant highest negative sca effects Kernel L/B ratio The sca effects ranged from to Eight hybrids showed significant positive sca effects. Highest positive significant effects were recorded by Akshyadhan x Improved Pusa Basmati (0.50) followed by NLR 145 x Basmati 370 (0.47), BPT 5204 x Sumathi (0.43) and RNR 2354 x Improved Pusa Basmati (0.26). The cross Sumathi x Improved Pusa Basmati recorded highest significant negative value of followed by Sumathi x Basmati 370 (-0.55) and BPT 5204 x Pusa 1121 (-0.38). Kernel size and shape has major impact on consumer s and miller s acceptance and slender rice (fine) is commercially accepted and fetch premium price in the market. The sca variance was higher than gca variance and with ratio of 0.53 and predominance of non-additive variance for these kernel traits indicated that the genetic variation is non-fixable in nature as such, straight selection would not be fruitful attempt. These results are in conformity with the findings of earlier researchers, Sanjeev Kumar et al. (2007b), Umadevi et al. (2010), Gonya nayak et al. (2011), Asfaliza et al. (2012) and Gnanamalar and Vivekanandan (2013a) Kernel length after cooking Nine crosses exhibited significant positive sca effects and thirteen crosses exhibited significant negative effects for this character. Highly significant positive values were associated with Akshyadhan x NLR 145 (2.71), Akshyadhan x Basmati 370 (2.67), Pusa 1121 x Sumathi (2.45) and BPT 5204 x RNR 2354 (2.37) cross combinations Kernel elongation ratio Out of twenty eight cross combinations studied, nine crosses exhibited significant positive sca effects and the highest by BPT 5204 x RNR 2354 (60.90) followed by Sumathi x Basmati 370 (48.17), Akshyadhan x NLR 145 (41.17), Akshyadhan x Basmati 370 (36.20) and BPT 5204 x NLR 145 (30.47) and thirteen crosses reported significant negative effects.

135 The analysis of gene actions for cooking quality attributes revealed preponderance of non- additive gene action, as the GCA variances were lower magnitude than SCA variances (0.21 and 0.12) for kernel length after cooking, kernel elongation ratio. Good et al. (1986), Sarathe et al. (1986), Munhot et al. (2000) Pradhan and Singh (2008), Shivani et al. (2009), Tyagi et al. (2010), Adilakshmi and Raghava reddy (2011) and Gonya nayak et al. (2011) through different studies reported similar results earlier. Under these circumstances, breeding methods that would enhance recombination and release hidden variability would be of immense help in bringing about certain desirable types Head rice recovery For the trait head rice recovery, sca effects were positively significant in four crosses only viz., BPT 5204 x NLR 145 (9.82), RNR 2354 x Sumathi (6.70), Pusa 1121 x RNR 2354 (6.36) and NLR 145 x Sumathi (4.97), while thirteen hybrids recorded significant negative values. Hybrid BPT 5204 x RNR 2354 recorded highest negative value of followed by BPT 5204 x Improved Pusa Basmati (-11.51) and Sumathi x Improved Pusa Basmati (-10.40). For head rice recovery, the GCA variance was less than SCA variance with ratio of 0.18 with predominance of non-additive gene action. Since non- additive genetic variation cannot be fixed, recurrent selection and selective diallel mating is advocated to break the gene constellations and release the free variability. Earlier researcher s Adilakshmi and Raghava reddy (2011), Gonya nayak et al. (2011) and Gnanamalar and Vivekanandan (2013a) reported similar findings. Summarizing the results, parents Akshyadhan and Sumathi were found to contribute favourable genes for yield. Improved Pusa Basmati combined well for grain characters (kernel length, kernel breadth, kernel length/breadth ratio, kernel length after cooking and kernel elongation ratio) and Basmati 370 for grain yield and quality characters (Table 4.13). Among the crosses investigated, Pusa 1121 x Sumathi (for days to 50% flowering); BPT 5204 x Basmati 370 (Plant height); Pusa 1121 x Basmati 370 and BPT 5204 x NLR 145 (number of productive tillers/plant); Sumathi x Improved Pusa Basmati and RNR 2354 x Sumathi (panicle length); RNR 2354 x Basmati 370 (number of filled grains per panicle); BPT 5204 x Pusa 1121 (panicle length, number of filled

136 grains/panicle, 1000 grain weight and grain yield); BPT 5204 x Akshyadhan (number of productive tillers/plant, number of filled grains/panicle and grain yield); Sumathi x Improved Pusa Basmati (panicle length, panicle weight, 1000 grain weight, kernel elongation ratio and grain yield); RNR 2354 x Improved Pusa Basmati (panicle length, number of filled grains/panicle, 1000 grain weight, kernel length, kernel breadth, kernel L/B ratio and grain yield); Pusa 1121 x Sumathi (kernel length and kernel L/B ratio); Akshyadhan x Improved Pusa Basmati (kernel L/B ratio) and NLR 145 x Pusa 1121 and Akshyadhan x Pusa 1121 (panicle length, panicle weight, 1000 grain weight and grain yield) were found to be the best specific crosses, as they had performed exceedingly well for yield as well as for quality parameters in terms of high per se performance, sca effects and gca of parents (high x high, high x medium). Details of top ranking crosses are collated in Table The present investigation also indicated that the best parents with high gca and high per se do not always combine well to yield best crosses. Promising general combiners for yield and quality characters are collated in Table In addition to this, the results also further showed that the best parents were the best general combiners for a particular trait but not for all the characters under consideration. Such results were observed by earlier investigators, Selvi et al. (2001), Rosamma and Vijayakumar (2007), Panwar (2005), Singh et al. (2007) and Sharma and Mani (2008). The undesirable sca effects exhibited by some crosses for different characters might be due to the presence of unfavorable genes in parents for the characters under consideration. Superiority crosses with high per se performance, sca effects for yield also exhibited high sca effects, significant heterosis and superiority at least for 2-3 component characters viz., BPT 5204 x Akshyadhan (for number of productive tillers/plant, no. of filled grains/panicle and grain yield per plant), BPT 5204 x Pusa 1121 (for panicle length, number of filled grains/panicle and grain yield per plant), Sumathi x Improved Pusa Basmati (for days to 50% flowering, panicle length, 1000 grain weight and grain yield per plant), RNR 2354 x Improved Pusa Basmati (for days to 50% flowering, panicle length, number of filled grains/panicle, grain yield per plant and kernel breadth) and Improved Pusa Basmati x Basmati 370 (for days to 50% flowering, number of productive tillers/plant, panicle weight/plant and grain yield per plant) (Table 4.15).

137 4.4 GENERATION MEAN ANALYSIS Lot of information is available on gene action and the results based on diallel and L x T design suggest that both additive and dominance types of gene effects are involved in the inheritance of various quantitative traits in rice (Chang et al., 1973). Though, the importance of epistatic gene effects have been reported, attempts made in this line is rarely reported especially with involvement of aromatic rice cultures. Further, studies on many generations involves tedious work, facilities like land and labour etc., as such, in the present study, an effort was made to unravel the genetic information related to non allelic interactions in expression of important yield and quality characteristics in aromatic rice. The mean values of five generations viz., P 1, P 2, F 1, F 2 and F 3 were utilized to study the inheritance of quantitative characters like grain yield, yield contributing traits and quality characters by using generation mean analysis. The scaling tests C and D indicated the presence of epistasis in expression of different characters. Presence of epistasis was detected based on the criteria that characters showing significance for any of the scales (C or D or both) indicated the presence of epistasis. The significance of C alone was taken as presence of dominance dominance (l) type of non-allelic interaction. The significance of D alone was taken as additive additive type. Existence of both additive additive and dominance dominance types of gene interaction was considered when C and D scales were significant. If none of the scaling tests was significant, it was considered as the absence of epistatic gene action (Mather and Jinks, 1971). Difference between generation means is a prerequisite to proceed with the analysis of generation means. Mean values showing significant differences along with standard errors of five generations (P 1, P 2, F 1, F 2 and F 3 ) of the ten crosses and scaling test values with respect to fourteen characters have been presented in table 4.16 to The five components viz., mean [m], additive [d], dominance [h], additive x additive [i] and dominance x dominance [l] gene effects obtained from analysis of five populations viz., parent 1, parent 2, F 1, F 2 and F 3 for fourteen characters of ten crosses viz., BPT 5204 x Akshyadhan, BPT 5204 x Pusa 1121, BPT 5204 x Sumathi, Akshyadhan x NLR 145, Akshyadhan x Pusa 1121, NLR 145 x Sumathi, RNR 2354 x Improved Pusa Basmati, RNR 2354 x Basmati 370, Sumathi x Improved Pusa Basmati

138 and Improved Pusa Basmati x Basmati 370 were estimated following perfect fit digenic interaction 5 parameter model and presented in table 4.16 to On knowing that the values of C and D scaling test were highly significant for all the fourteen characters under study, further analysis was continued following the Joint Scaling Test (3 parameter model) to confirm the presence of epistasis, both the tests indicated that the additive dominance model was inadequate to explain the inheritance of the characters. Due to the presence of non allelic interactions for all the characters data were subjected to further analysis using five parameter (assuming digenic interaction) model as suggested by Jinks and Jones, (1958). Keeping view the elaborate discussion made under the heading heterosis and inbreeding depression, further discussion on generation means were slightly restricted and more information was provided on non-allelic interactions Yield characters Days to 50 percent flowering For days to 50 percent flowering, the individual scaling tests (C and D) and X 2 value of joint scaling were observed to be highly significant revealing the inadequacy of the additive dominance model (Table 4.17). All the crosses flowered early as compared to their respective better parent except in case of BPT 5204 x Pusa 1121 indicating predominantly the decreasing effects of dominant alleles (Table 4.16). In the F 2 population, the progenies produced by all the crosses had mean values intermediate to their corresponding parents except in three crosses, BPT 5204 x Akshyadhan, BPT 5204 x Sumathi, RNR 2354 x Basmati 370 where the mean values were higher than their corresponding parents. In F 3, in all the entire cross combinations, the mean were lower than their corresponding parents, except in BPT 5204 x Akshyadhan which had higher mean values than their corresponding parents. For days to 50 percent flowering, all the crosses exhibited highly significant and positive dominance [h] gene effects and these were higher in magnitude than additive effects (Table 4.18). Both additive and non additive gene actions were emphasized by Hasib et al. (2002) for improvement of earliness in aromatic rice with respect to nonallelic interactions component, the additive x additive [i] interaction effects were positive and higher in magnitude in all crosses except in BPT 5204 x Akshyadhan which had negative and significant interaction effects (Table 4.25). On the other hand, dominance x dominance [l] interaction effects were negative and significant in all the

139 crosses studied except in BPT 5204 x Akshyadhan. The dominance [h] and dominance x dominance [l] effects were in opposite direction for all the crosses studied which indicated that duplicate type of epistasis was important in expression of days to 50 per cent flowering which is difficult to improve. Such findings were also reported by Roy and Panwar (1993), Liang et al. (1996), Murugan and Ganesan (2006) and Nayak et al. (2007). Direct selection in one cross (Akshyadhan x NLR 145) would be useful to evolve early lines, as the d effects were significant Plant height (cm) In F 1 generation mean values of plant height (Table 4.19) were higher than their respective higher parent in BPT 5204 x Pusa 1121 and RNR 2354 x Improved Pusa Basmati where as for remaining eight crosses the values were intermediate to their parents. Significance of X 2 value of joint scaling test and C, D scaling tests revealed the inadequacy of additive dominance model and presence of epistasis in the inheritance of the character (Table 4.20). Among the F 2 populations, two crosses, BPT 5204 x Pusa 1121 and Akshyadhan x NLR 145 produced F 2 progeny which recorded higher means than parents due to dominance nature of negative genes in F 1 generation and two crosses BPT 5204 x Akshyadhan and RNR 2354 x Basmati 370 recorded lower means than parents due to inbreeding depression and remaining six crosses recorded intermediate means over their parents. The progenies of BPT 5204 x Akshyadhan, Akshyadhan x NLR 145, Akshyadhan x Pusa 1121 and Sumathi x Improved Pusa Basmati exhibited intermediate mean values and progenies of remaining six crosses exhibited lower mean value to their parents in F 3 population, this revealed that in the genetic variation the gene effects were mostly of dominant nature, as high heterosis was followed by high inbreeding depression. Due to significant additive [d] gene effects in the crosses viz., BPT 5204 x Akshyadhan, BPT 5204 x Pusa 1121, BPT 5204 x Sumathi, NLR 145 x Sumathi, RNR 2354 x Basmati 370 and Improved Pusa Basmati x Basmati 370, single plant selection of dwarf types is suggested. Dominance [h] and dominance x dominance [l] effects were in opposite direction, indicating role of duplicated epistasis (Table 4.21). Due to mutual cancellations of dominance effects, the i type of interaction was predominant but towards undesirable positive side.

140 Number of productive tillers per plant For productive tillers per plant, all the ten crosses exhibited significant differences for their generation means. The crosses viz., BPT 5204 x Pusa 1121, Akshyadhan x NLR 145, RNR 2354 x Improved Pusa Basmati and RNR 2354 x Basmati 370 recorded lower values than parents (Table 4.22). Moreover in F 2 population, all the crosses recorded higher means compared to parents except Akshyadhan x Pusa The F 3 progenies of the crosses viz., BPT 5204 x Sumathi, Akshyadhan x NLR 145, Akshyadhan x Pusa 1121, NLR 145 x Sumathi, RNR 2354 x Improved Pusa Basmati, RNR 2354 x Basmati 370 and Improved Pusa Basmati x Basmati 370 registered higher mean values than their F 2 s and F 1 s. It indicated that due to the presence of higher number of dominant genes with negative effects, the F 1 mean was low and subsequent fixation of genes in later generations resulted in higher per se performance. The scaling tests C and D significantly deviated from zero indicating the inadequacy of the simple additive dominance model. Significance of X 2 value further strengthened validity of these results. Both C and D scales were significant in all the crosses except in BPT 5204 x Akshyadhan, which suggested that simple additive and dominance model was inadequate and non-allelic interactions were involved in its inheritance (Table 4.23). The dominance [h] effects were highly significant and negative in all the crosses except BPT 5204 x Akshyadhan which had positive significant [h] effects. With respect to d component, the effects were significant in all the crosses. Among the interaction effects, negative and significant values were noticed for additive x additive [i] type except in case of BPT 5204 x Akshyadhan (Table 4.24). For dominance x dominance [l], negatively significant values were registered in case of BPT 5204 x Akshyadhan, BPT 5204 x Pusa 1121, Akshyadhan x NLR 145 and Sumathi x Improved Pusa Basmati but positive and significant estimates were found in cross combinations of BPT 5204 x Sumathi, NLR 145 x Sumathi, RNR 2354 x Improved Pusa Basmati and RNR 2354 x Basmati 370. In five crosses the dominance [h] and dominance x dominance [l] effects were in opposite (Duplicate epistasis) direction. Verma et al. (2006), Nayak et al. (2007) and Anil Kumar and Mani (2010) also reported duplicate epistasis in most of the crosses for productive tillers as in the case of present study. Higher estimates of additive [d] type component were registered with respect to

141 the crosses, Sumathi x Improved Pusa Basmati, BPT 5204 x Akshyadhan and Improved Pusa Basmati x Basmati 370, which indicated the scope of direct selection for improvement of this trait (Robin, 1997 and Thirugnana kumar et al., 2007) Panicle length (cm) Epistatic gene effects existed for panicle length also and among the interaction effects, additive x additive [i] gene effects were positively significant in six crosses studied and within these, two specific crosses, Akshyadhan x NLR 145 and Akshyadhan x Pusa 1121 were considered as best crosses from selection point of view as both d and i' types were in positive direction with high per se performance. Positive and significant dominance x dominance [l] effects were noticed in four crosses, whereas in the remaining six crosses negative [l] effects were predominant (Table 4.27). The epistasis was of duplicate type for seven crosses studied as was reported by Verma et al., (2006) Panicle weight (g) Non-allelic interactions were also responsible for the inheritance of this trait as indicated by the significance of scaling tests and Joint scaling test (Table 4.29). Among the five generations, the mean value of panicle weight for F 1 generation exceeded that of the better parent (Table 4.28). Many crosses had significant additive [d] gene effects for panicle weight, while dominance [h] effects were positive and significant in all the crosses except RNR 2354 x Basmati 370 (Table 4.30). The additive x additive [i] interaction effects were positive and significant for six crosses and remaining four crosses had negatively significant [i] effects. The dominance x dominance [l] effects was positively significant in case of seven crosses which indicated a unidirectional dominance. The directions of gene effects viz., dominance [h] and dominance x dominance [l] were opposite for 50 per cent of the crosses. Pedigree selection would be highly rewarding incase of 4 crosses viz., BPT 5204 x Pusa 1121, Akshyadhan x NLR 145, Akshyadhan x Pusa 1121 and Sumathi x Improved Pusa Basmati, as their d and i' components were significant with high per se performance with respect to panicle weight.

142 Number of filled grains for panicle F 1 hybrids of Akshyadhan x Pusa 1121 and Improved Pusa Basmati x Basmati 370 showed intermediate expression to their parents (Table 4.31) while the remaining F 1 s exceeded their parents in grain number. However in F 2 generation, all the crosses registered intermediate values on their respective parental means except, BPT 5204 x Akshyadhan whose mean value was less than that of parents. Many cross combinations had intermediate to lower mean estimates in F 3 generation, which indicated that number of grains is a highly non fixable trait in rice. The additive [d] gene effects were significant and higher in magnitude for filled grains per panicle in cross combinations, BPT 5204 x Pusa 1121, BPT 5204 x Sumathi, Akshyadhan x NLR 145, Akshyadhan x Pusa 1121, RNR 2354 x Improved Pusa Basmati, Sumathi x Improved Pusa Basmati and Improved Pusa Basmati x Basmati 370 (Table 4.33), whereas the remaining crosses had low [d] effects. All crosses recorded highly significant and positive dominance [h] effects and in addition, dominance x dominance [l] effects was also positive and high in six crosses. Non additive gene effects viz., [h] as well as [l] were predominant over additive gene effects, indicating the existence of non fixable genetic variation for grains per panicle. Preponderance of non additive gene action was also earlier reported by Annadurai and Nadarajan (2001), Bidhan Roy and Mandal (2001), Murugan and Ganesan (2006) and Patil et al. (2006a). This resulted sever inbreeding depression in most of the crosses subsequently. However, scope of improvement for grains per panicle through single plant selection could not be ruled out in certain crosses like BPT 5204 x Sumathi and Akshyadhan x Pusa 1121 in which i' type of interaction coupled with significant d effects prevailed largely. The opposite signs of [h] and [l] in crosses like BPT 5204 x Sumathi, Akshyadhan x NLR 145, NLR 145 x Sumathi and RNR 2354 x Basmati 370 and same signs in six crosses indicated the presence of both duplicate and complementary epistasis, for grains per panicle (Anil Kumar and Mani, 2010). In some crosses, higher magnitude of heterosis was experienced for grains per panicle largely due to dominance and interaction between increasing dominant genes in such crosses, heterotic breeding would be highly rewarding in comparison to selection in segregating generations on an overall basis to reap immediate benefits provided feasible male

143 steriles are generated (Koodalingam 1994; Vaithilingam 1995; Murugan and Ganesan 2006; Patil et al., 2006b; Verma et al., 2006; and Thirugnanakumar et al. 2007) grain weight F 1 generation means of Akshyadhan x Pusa 1121, NLR 145 x Sumathi, RNR 2354 x Improved Pusa Basmati and Sumathi x Improved Pusa Basmati were higher than those of respective parents (Table 4.34). Whereas, in case of BPT 5204 x Akshyadhan, BPT 5204 x Pusa 1121, BPT 5204 Sumathi, Akshyadhan x NLR 145, RNR 2354 x Basmati 370 and Improved Pusa Basmati x Basmati 370 they were at mid point. Varying trends were observed in F 2 and F 3 generations, means of all the progenies were almost at the midpoint except in case of Akshyadhan x Pusa 1121, NLR 145 x Sumathi, RNR 2354 x Improved Pusa Basmati and Sumathi x Improved Pusa Basmati. For test weight, the [d] estimates were significant in all the crosses and higher in magnitude in cross combinations, BPT 5204 x Akshyadhan, Akshyadhan x NLR 145, BPT 5204 x Pusa 1121 and BPT 5204 x Sumathi (Table 4.36). Significant additive [d] gene effects were reported by Dhanakodi and Subramanian (1998) and Thirugnanakumar et al. (2007) recommending direct selection to develop pure lines with higher test weight. All crosses, except Sumathi x Improved Pusa Basmati recorded highly significant and positive dominance [h] effects. This indicated that, the dominant gene effects were positive, whereas the additive gene effects were negative on the whole. Study revealed that, Additive x additive [i] effects was negatively significant, expressed in all the crosses except Akshyadhan x NLR 145, Akshyadhan x Pusa 1121 and Improved Pusa Basmati x Basmati 370. The interaction effects due to dominance x dominance [l] were negative and significant in all the crosses except one cross viz., Sumathi x Improved Pusa Basmati. The signs for dominance [h] and dominance x dominance [l] components were in opposite side for all the crosses studied revealing the greater role of duplicate epistasis (Thirugnanakumar et al., 2007). Among the crosses investigated, Akshyadhan x NLR 145 and Akshyadhan x Pusa 1121 were the best superior crosses from the point of recovering the homozygous lines with very high test weight, as the additive x additive [i] and additive [d] components were positive and highly significant in these two crosses. In rest of the crosses, direct selection for higher

144 test weight may not be much fetching due to preponderance of dominance [h] effects as well as duplicate epistasis. When both additive and non additive effects are important, the use of population improvement concept may become an amenable solution. Frey (1982) explained the use of this technique in highly autogamous crop. Biparental mating, recurrent selection and selective diallel mating system (Janson, 1970) might be more profitable Grain yield per plant Scaling tests (C and D) as well as joint scaling test (X 2 for 2 d.f) indicated that simple additive - dominance model was inadequate to explain the inheritance of grain yield (Table 4.38). The estimates of dominance [h] were high in comparison to those of additive [d] except in case of Akshyadhan x Pusa 1121 and Sumathi x Improved Pusa Basmati. The F 1 s of BPT 5204 x Akshyadhan, BPT 5204 x Pusa 1121, BPT 5204 x Sumathi, NLR 145 x Sumathi, RNR 2354 x Improved Pusa Basmati, RNR 2354 x Basmati 370, Sumathi x Improved Pusa Basmati and Improved Pusa Basmati x Basmati 370 exhibited better yield performance over their parents while in case of Akshyadhan x NLR 145 and Akshyadhan x Pusa 1121 the yield levels were almost at mid parental value (Table 4.37). In F 2 generation, the mean of NLR 145 x Sumathi exceeded midpoint and with respect to remaining crosses, the values were near to the average performance of their parents. Many cross progenies exhibited intermediate yield performance to their parents in F 3 generation indicating the predominant role of non-additive gene effects, which includes dominance and dominance x dominance types (Table 4.39). Five crosses viz., Akshyadhan x Pusa 1121, Improved Pusa Basmati x Basmati 370, BPT 5204 x Akshyadhan, Sumathi x Improved Pusa Basmati and RNR 2354 x Improved Pusa Basmati registered significant and higher magnitude additive [d] gene effects for grain yield. Predominant role of dominance [h] effects were observed for all the crosses studied, except RNR 2354 x Improved Pusa Basmati. Most of the crosses exhibited dominance x dominance (l) type of interactions very significantly for grain yield as was observed by Subramanian (1994). Over view of mean values of different generations (F 1 to F 3 ) clearly indicated a gradual decrease in generation means from F 1 to F 3 on inbreeding. The superior performance in preceding generations was mainly due to governance of dominance [h] and dominance x dominance [l] type of gene effects (complementary epistasis). In the present study, 6 crosses registered complementary epistasis and 3 crosses duplicate epistasis as

145 observed by Patil et al., (2006). The observed genetic variation for grain yield per plant was of mostly non heritable (non additive) type, hence direct selection for grain yield would not be a worthy attempt. Instead, recurrent selection and bi-parental mating would be advantageous with crosses like BPT 5204 x Akshyadhan, BPT 5204 x Pusa 1121 and Improved Pusa Basmati x Basmati 370 in view of F 1 s showing superiority due to complementary epistasis ( h and l were positive) Grain characters Kernel length (mm) A comparative study of generation means indicated that, in F 1 generation, 6 crosses expressed mean kernel length at intermediate level and two crosses viz., BPT 5204 x Sumathi and Akshyadhan and NLR 145 had higher means and Sumathi x Improved Pusa Basmati and Improved Pusa Basmati x Basmati 370 had low expression as compared to their parental values. In case of F 2 s, one cross with higher and three crosses with lower mean values and the remaining crosses with intermediate values when compared with parental means (Table 4.40). The progenies of Sumathi x Improved Pusa Basmati and Improved Pusa Basmati x Basmati 370 exhibited lower mean values and those of the remaining crosses exhibited almost intermediate mean values to their parents in F 3 generation. Highest estimates were recorded in F 1 generation and further advancement resulted in gradual decline in mean performance and high heterosis was accompanied by high inbreeding depression for kernel length. Except in two crosses viz., Sumathi x Improved Pusa Basmati and Improved Pusa Basmati x Basmati 370, the additive [d] and additive x additive [i] gene effects were negative and significant for kernel length. The dominance [h] effects were positive and significant in BPT 5204 x Pusa 1121, BPT 5204 x Sumathi, NLR 145 x Sumathi, RNR 2354 x Improved Pusa Basmati, Sumathi x Improved Pusa Basmati and Improved Pusa Basmati x Basmati 370 and in the remaining crosses they were negatively significant and these effects were higher than the additive effects (Table 4.42). Importance of both additive and dominance effects for kernel length was earlier emphasized by Roy and Panwar (1993) and Vivekanandan and Giridharan (1995) in rice. Further, they also indicated the importance of all types of interaction effects for inheritance of this trait as observed in present study. In the present investigation, two promising crosses viz., Sumathi x Improved Pusa Basmati and Improved Pusa Basmati x Basmati 370 with good per se and significant additive [d] and additive x additive [i] components of genetic variation could be best exploited for evolving pure lines with

146 increased kernel length through pedigree breeding. As regard to other crosses, where the dominant and dominant x dominant effects are prominent, intermating of F 2 s detaining selection in early generation might be a good perspective. When the components [h] and [l] are with opposite signs, it shows duplicate gene action between dominant decreasing genes (Hayman and Mather, 1955). Such type of epistasis in the present investigation was associated with six crosses Kernel breadth (mm) Dominant genes with negative effects are desirable for developing slender grained varieties, such type of additive [d] gene effects were observed in the crosses, BPT 5204 x Akshyadhan, BPT 5204 x Pusa 1121, BPT 5204 x Sumathi, Akshyadhan x Pusa 1121, RNR 2354 x Basmati 370 and Improved Pusa Basmati and Basmati 370 and additive x additive [i] type of interaction effects were significant and negative in BPT 5204 x Akshyadhan, BPT 5204 x Pusa 1121, BPT 5204 x Sumathi, Akshyadhan x Pusa 1121, NLR 145 x Sumathi and Improved Pusa Basmati x Basmati 370 (Table 4.45). Among the ten crosses studied, these two (BPT 5204 x Pusa 1121 and BPT 5204 x Sumathi) were found to be highly useful for selection as the [d] and [i] components were on negative side (complementary epistasis). Dominant variation was most predominant in comparison to additive genetic variation, as evident from the higher magnitudes of [h] and [l] components. Among ten crosses studied, only few crosses registered negatively significant dominance x dominance[l] gene effects. The [h] and [l] effects were found to be in opposite direction in eight crosses for kernel breadth Kernel L/B ratio An intermediate expression was noticed for the mean length/ breadth ratio in F 1 generation with almost same trend in F 2 generation. This main reason was being that the dominant effects were on negative side, coupled with duplicate epistasis. One cross Akshyadhan x NLR 145 had higher and two crosses viz., BPT 5204 x Akshyadhan and Sumathi x Improved Pusa Basmati had lower estimates as compared to their corresponding parental averages (Table 4.46). The additive[d] gene effects were significant in all the crosses except Sumathi x Improved Pusa Basmati and Gnanamalar and Vivekandan (2013c) also observed predominant role of additive gene effects for this trait. With respect to the dominance [h] effects, they were significant and positive in case of BPT 5204 x Pusa 1121,

147 BPT 5204 x Sumathi, Akshyadhan x Pusa 1121, NLR 145 x Sumathi, Sumathi x Improved Pusa Basmati and Improved Pusa Basmati x Basmati 370 and in the remaining crosses they were negative. With regard to non allelic interactions, additive x additive[i] components were positive and significant only in 2 crosses viz., Sumathi x Improved Pusa Basmati and Improved Pusa Basmati x Basmati 370, whereas, significant and negative i effects were observed in remaining 8 crosses. For this quality trait, the magnitudes of h and l were high in comparison to those of d and i in general. The direction for dominance [h] and dominance x dominance [l] gene effects was in opposite sides for all the crosses except for BPT 5204 x Sumathi (Hasib et al., 2002). Only in one cross, Akshyadhan x Pusa 1121 complementary epistasis was observed but in undesirable negative side (Table 4.48). Fixable genetic variation ( d & i') with high per se in F 2 was observed in one cross (Improved Pusa Basmati x Basmati 370), hence selection of superior plants in early generations for higher kernel L/B ratio in this particular cross would be highly rewarding as compared to other crosses. Further, the chances of recovering desirable types in another cross (Sumathi x Improved Pusa Basmati) in which the higher estimates of i' component was realized could not be ruled out Kernel length after cooking Mostly, fixable gene effects ( d & i') were on negative side, whereas the unfixable ( h & l ) effects were on positive side, indicating limited scope for improvement through direct selection. All the crosses showed significant additive [d] gene effects for kernel length after cooking. Predominant role of dominance [h] effects were observed for expression of this trait. All the cross combinations except BPT 5204 x Akshyadhan, BPT 5204 x Pusa 1121 and BPT 5204 x Sumathi expressed positive and significant l type of interaction. Complementary epistasis was noticed in six crosses in the present investigation. However, in view of registering significant d and i' estimates coupled good mean performance in 3 crosses (Improved Pusa Basmati x Basmati 370, BPT 5204 x Akshyadhan and BPT 5204 x Pusa 1121), a direct selection for this quality trait, linear elongation after cooking is recommended from F 2 generation itself. It is fortunate that, same cross (Improved Pusa Basmati x Basmati 370) exhibited excelled performance for other quality character too viz., kernel length and kernel L/B ratio (Table 4.51).

148 Kernel elongation ratio The estimates of kernel elongation ratio with respect to the crosses, BPT 5204 x Pusa 1121, Akshyadhan x Pusa 1121, RNR 2354 x Improved Pusa Basmati, Sumathi x Improved Pusa Basmati and Improved Pusa Basmati x Basmati 370 were almost at mid parental value (Table 4.52). While in case of crosses, Akshyadhan x NLR 145 and RNR 2354 x Basmati 370, the mean values were higher than their corresponding better parents and in the remaining crosses the mean performance was poorer than parents. In the F 2 generation, the performance of BPT 5204 x Pusa 1121 was better with increased mean values in comparison to their respective parents. While, the crosses BPT 5204 x Akshyadhan, BPT 5204 x Sumathi, Akshyadhan x Pusa 1121, RNR 2354 x Basmati 370 and Improved Pusa Basmati x Basmati 370 recorded average performance in this generation indicting presence of less residual heterosis. The additive[d] gene effects played important role in all crosses except RNR 2354 x Improved Pusa Basmati and Sumathi x Improved Pusa and significant and positive dominance [h] gene effects were observed only in three crosses. Anil Kumar and Mani (2010) emphasized the importance of both additive and non-additive gene effects for improvement of linear elongation of kernels after cooking (Table 4.54). Among the non allelic interaction effects, additive x additive [i] gene effects were chiefly responsible for linear elongation of kernels in all the crosses studied except in RNR 2354 x Improved Pusa Basmati and Sumathi x Improved Pusa Basmati, and with regard to dominance x dominance [l] effects they were positive in six crosses. Duplicate type of epistasis was significant in eight crosses studied. However, both the types of interaction (duplicate and complementary) were reported by Anil Kumar and Mani (2010). Irrespective of length of the kernel, certain lines exhibit good elongation ability, commanding good premium in the market, in this context, pedigree breeding appears to be highly useful in case of 4 crosses (BPT 5204 x Akshyadhan, BPT 5204 x Pusa 1121, BPT 5204 x Sumathi and Improved Pusa Basmati x Basmati 370) as the d and i' components were positive and significant Head rice recovery Among many quality parameters, milling recovery in terms of net rice plays crucial role from miller s point of view. Many times, varieties with exceptional cooking quality and higher grain yield potential would be rejected by millers for want of high head rice recovery. In the present investigation, the F 1 mean of NLR 145 x Sumathi was

149 found to be higher than that of better parent, whereas the performance of remaining crosses was average (Table 4.55). Further, there was a decline in per se in F 2 population in all the crosses recording lesser values than their parental means except BPT 5204 x Pusa 1121 and BPT 5204 x Sumathi, in which the performance was intermediate. Similarly, in F 3, the progenies of six crosses exhibited lower means and progenies of four crosses exhibited intermediate means, when a comparison was made with their respective parents. Dominance h effects were positive and significant in case of four crosses and they were negative h effects in the remaining six crosses. Among the epistatic interaction effects, additive x additive [i] gene effects were positively significant in all the crosses studied except in Akshyadhan x Pusa 1121 and Improved Pusa Basmati x Basmati 370 and the dominance x dominance [l] effects were positively significant 6 crosses (Table 4.57). The direction of gene effects viz., dominance [h] and dominance x dominance [l] were in opposite (duplicate epistasis) for eight crosses studied. It was clearly understood that, non allelic interaction effects were also present in higher magnitude besides main effects influencing the inheritance of head rice recovery. A heavy drop in per se in F 2 and F 3 was recognized particularly in crosses viz., Akshyadhan x NLR 145 and Akshyadhan x Pusa 1121and the reason was attributed to presence of higher estimates of unfixable genetic variation viz., l type. In view of the above findings, straight selection only in 2 crosses (BPT 5204 x Sumathi and NLR 145 x Sumathi) may have some advantage for head rice recovery. In a highly self pollinated crop like rice, the easy and economical method of crop improvement is pedigree selection and development of promising homozygous lines, provided the traits under consideration are largely governed by additive and additive x additive type of gene effects. Most of the time, high amount of heterosis is miss interpreted as presence of either over dominance or directional dominance of unlinked and reinforcement of linked genes, but it is not so, and the real fact for exceptional expression of a trait especially in F 1 generation also lies with dispersion of desirable genes in parents. Hence, in the present study, a critical exercise was made and finally 10 promising crosses were chosen for generations mean analysis. This study confirmed that, in addition to main effects (additive/dominance) the non allelic interaction effects were also present in expression of desirable metric traits related to yield and quality (Table 4.58).

150 Keeping in view, the magnitudes of fixable genetic variation ( d & i types) and per se performance in F 2 generation in comparison to F 1 s and respective parents, immediate selection in segregating generations/intercrossing and advancing in certain crosses viz., BPT 5204 x Sumathi, RNR 2354 x Basmati 370 and Sumathi x Improved Pusa Basmati (for yield and quality) and BPT 5204 x Akshyadhan, Akshyadhan x NLR 145, Akshyadhan x Pusa 1121 (for grain yield) and BPT 5204 x Pusa 1121, Improved Pusa Basmati x Basmati 370 (for quality alone) is expected to be highly feasible and assured for further gains in rice.

151 4.5 ESTIMATES OF MEAN, VARIABILITY, HERITABILITY AND GENETIC ADVANCE IN F 2 AND F 3 GENERATIONS F 2 GENERATION The existence of variability in the breeding material is the first and foremost point in selection for improvement. Environmental effects influence the total observable variations of quantitative traits. Therefore, partitioning of overall variance due to genetic and non-genetic causes becomes necessary for effective breeding programme. The genotypic coefficient of variation estimates the heritable variability, whereas phenotypic component measures the role of environment on the genotype. High PCV and low GCV for a character indicates high influence of environment in its expression. The phenomenon of transmission of characters from parents to offspring is usually measured in terms of heritability. When it is estimated in narrow sense based on the additive variance, which is fixable in nature gives highly fruitful results through simple selection procedures. The F 2 generation is critical for success of breeding programme because there are remote chances of finding superior recombinants in advanced generations if there is lack of desirable segregants in F 2 populations. Therefore the estimates of heritability in narrow sense and genetic advance would help to estimate realizable improvement through formulation of a sound breeding programme. GCV, PCV, heritability in narrow sense and genetic advance as percentage of mean were estimated for yield and quality characters to study F 2 generation as whole population (Table 4.59). The values were treated as high, moderate and low as per the categorization proposed by Siva Subramanian and Madhavamenon (1973) for variability and Johnson et al. (1955) for heritability as well as genetic advance as per cent of mean. A wide range of variation was observed among 28 F 2 crosses for fourteen characters. The perusal of data revealed that variance due to treatment was highly significant for all the characters exhibited by the genotypes. Significant genetic variation in various component characters was observed among the crosses and phenotypic variance was higher than genotypic variance for all the characters thus indicating the influence of environment factor on these traits. Similar findings were earlier reported by Mishra et al. (2003), Devi et al. (2006), Sarkar et al. (2007),

152 Manoj Kumar Prajapati et al. (2011), Singh et al. (2011), Ananadarao et al. (2011) and Bhadru et al. (2012) Days to 50% flowering The mean for days to 50% flowering was 110 days with a range of 100 days (Pusa 1121 x Sumathi) to 120 days (BPT 5204 x NLR 145). Days to 50% flowering had PCV of 5.59 per cent and GCV of 5.26 per cent with high heritability (62) and with moderate genetic advance as per cent of mean (14.25). Sinha et al. (2004), Vaithiyalingan and Nadarajan (2006) and Krishna et al. (2008) reported low genotypic and phenotypic coefficients of variation for this trait. Moderate-high heritability and low genetic advance was reported earlier by Madhavilatha et al. (2005), Vijaya lakshmi et al. (2008), Krishna et al. (2008) Akinwale et al. (2011), Ravindra babu et al. (2012), Rajesh Kumar Dhanwani et al. (2013) and Vanisree et al. (2013) Plant height The range for this character was from 91 cm (BPT 5204 x Akshyadhan) to 148 cm (Akshyadhan x NLR 145) with a mean value of 122 cm. The phenotypic coefficients of variation and genotypic coefficients of variation were medium with and per cent respectively. These results are in conformity with the findings of Patil et al. (2003) and Krishna et al (2008), Singh et al. (2011), Manoj kumar et al. (2011) and Rajesh Kumar Dhanwani et al. (2013). Medium heritability (50 per cent) coupled with high genetic advance (35.09 per cent) was observed for this character. These findings were in accordance with the earlier reports of Suman (2003) and Patil and Sarawgi (2005), Immanuel Selvaraj et al. (2011), Pawan Saini et al. (2013) and Ashok Kumar Tuwar et al (2013) Number of productive tillers per plant This trait ranged from a low value of 9.5 (Akshyadhan x Basmati 370) to high value of 15.1 (BPT 5204 x Pusa 1121) with a mean of Besides having moderate PCV (18.52 per cent) and moderate GCV (16.17 per cent), this component exhibited medium heritability of 32 per cent in association with high genetic advance as percentage of mean (37.26 per cent). Vivek et al. (2005) and Ashok Kumar Tuwar et al. (2013) also reported similar findings.

153 Panicle length The trait Panicle length had mean value of 25.8 cm with the range of 18.6 to 29.6 cm whereas genotypic coefficient of variation was low (8.75 per cent) and phenotypic coefficient of variation was medium (13.49 per cent) as reported by Nath and Talukdar (1997), Nayak et al (2002), Manoj kumar et al. (2011) and Rajesh Kumar Dhanwani et al. (2013). Low heritability (22 per cent) along with low genetic advance (4.45) was reported for this trait (Chikkalingaiah et al. 1999; Nagajyothi, 2001; Tara Satyavathi et al and Patil et al. 2003) and indicated that heritability was mostly due to non additive gene action hence good response is expected for heterosis breeding Panicle weight Range for this character was from 11.8 to 34.2 g with a mean of 27.4 g. GCV and PCV values recorded were moderate (18.09 and per cent respectively). Low heritability (29 per cent) and medium genetic advance (12.26 per cent) with high genetic advance as percentage of mean (44.32 per cent) was observed for this trait. Such lower values of narrow sense heritability and genetic advance, indicates that panicle weight is largely controlled by non-additive gene action Number of filled grains per panicle A mean of 91.1, range from 34.4 (RNR 2354 x Sumathi) to (NLR 145 x RNR 2354) between the entries was recorded for this trait. This trait had high variability of (PCV) and (GCV). Moderate heritability (37 per cent) in association with high genetic advance (84.0 per cent) was observed for filled grains per panicle, which indicated that improvement could be possible through selection in few selective crosses having high mean values and were likely to give desirable segregants in future generations. Earlier, Venkata Suresh (2001), Patil et al. (2003), Suman et al. (2005), Sankar et al. (2006), Vaithiyalingan and Nadarajan (2006), Nayak et al. (2007) and Chandra Kishore et al. (2008) also reported high heritability and genetic advance for filled grains per panicle, Nayak et al. (2002), Suman et al. (2005), Nayudu et al. (2007), Krishna et al. (2008), Bisne et al. (2009), Venkata Subbaiah et al. (2011), Pawan Saini et al. (2013), Rajesh Kumar Dhanwani et al. (2013), Ravindra babu et al. (2012) and Vanisree et al. (2013) also reported high variability, heritability and genetic advance for this trait.

154 grain weight The range for this character was from to g with a mean value of g. Moderate PCV and GCV recorded was and per cent respectively. Moderate heritability (37 per cent) coupled with high genetic advance was observed for this character. Sinha et al. (2004), Hasib (2005) and Chandra Kishore et al. (2008) reported higher magnitudes of heritability coupled with moderate values of genetic advance for this yield component Grain yield per plant The range for this character was from 7.3 (RNR 2354 x Sumathi) to 27.6 g (NLR 145 x Basmati 370) with a mean value of 19.9 g. A high genotypic coefficient of variation (23.67) and phenotypic coefficient of variation (26.92) were observed for this trait. The results were in agreement with the findings of Karim et al. (2007), Nayudu et al. (2007), Krishna et al (2008) Manoj kumar et al. (2011), Singh et al. (2011), Pawan Saini et al. (2013) and Rajesh Kumar Dhanwani et al. (2013). High heritability estimates (70 per cent) coupled with moderate genetic advance (11.05 per cent) and high genetic advance as per cent of mean (54.92 per cent) were recorded for grain yield per plant. Sinha et al (2004), Patra et al (2006), Akinwale et al. (2011), Manoj kumar et al. (2011), Venkata Subbaiah et al. (2011), Pawan Saini et al. (2013), Rajesh Kumar Dhanwani et al. (2013) and Vanisree et al. (2013) also reported results in similar lines Kernel length (mm) The trait kernel length had mean value of 5.87 mm with the range of 5.01 to 6.67 mm. The genotypic (9.11) and phenotypic (9.73) coefficients of variation were low. The results were in conformity with the findings of Krishna et al (2008), Venkata Subbaiah et al. (2011) and Vanisree et al. (2013). The heritability estimates for this trait were high (78 per cent) with a very low genetic advance (1.34 per cent) and high genetic advance as per cent of mean (22.55 per cent). This trait was predominantly influenced by additive genetic effects, which offer better scope of isolation of pure lines through direct selection schemes. Similar results were also reported by Surender Raju et al. (2002), Nayak et al. (2003) and Vanisree et al. (2013).

155 Kernel breadth (mm) Lowest kernel breadth of 1.50 mm was observed in the cross BPT 5204 x NLR 145. Highest mean performance (1.78 mm) was observed in case of Akshyadhan x NLR 145 with a mean of 1.64 mm. A low genotypic (5.53) and phenotypic (6.54) coefficients of variation were observed for this trait. For this trait, the heritability estimates were low (25) with a very low genetic advance (0.21 per cent) and moderate genetic advance as per cent of mean (12.31 per cent). These findings are in accordance with the earlier reports of Chaudhary and Motiramani (2003), Surender Raju (2002), Venkata Subbaiah et al. (2011) and Ravindra babu et al. (2012) Kernel L/B ratio The mean values ranged from 3.14 (BPT 5204 x Akshyadhan) to 4.17 (Pusa 1121 x Improved Pusa Basmati) with a mean of High PCV and low GCV recorded were and 8.88 per cent respectively. The heritability estimates were high (78 per cent) with a very low genetic advance (0.75) and high genetic advance as per cent of mean (20.80 per cent). Similar results were also reported by Madhavilatha et al (2005), Vijaya lakshmi et al. (2008), Ravindra babu et al. (2012) and Vanisree et al. (2013) Kernel length after cooking (mm) The observed range was from 8.48 mm (Akshyadhan x NLR 145) to mm (BPT 5204 x Pusa 1121) while the mean value reported for this trait was 9.48 mm. The GCV (11.17 per cent) and PCV (12.09 per cent) was high where as the heritability was medium (42 per cent) with a high genetic advance as percentage mean (27.25) Kernel elongation ratio The mean values ranged from 1.39 (NLR 145 x Sumathi) to 2.06 (BPT 5204 x Pusa 1121) with a mean of 1.62, GCV and PCV recorded was 8.82 and per cent respectively. The medium heritability of 33 per cent and moderate genetic advance as per cent mean of per cent was observed for this trait Head rice recovery per cent For this trait, moderate PCV (20.47 per cent) and high GCV (19.25 per cent) with low heritability of 26.0 per cent and high genetic advance as per cent mean of

156 47.78 was observed for this character. The range of head rice recovery per cent was from 26.4 to 57.7 with a mean of per cent was observed. The characters studied in the present investigation exhibited low, moderate and high PCV and GCV values. Among the yield characters, highest PCV and GCV values were recorded for number of filled grains/panicle followed by grain yield per plant and the lowest PCV and GCV values were recorded for days to 50% flowering. Among the grain quality characters highest PCV and GCV values were recorded for head rice recovery and lowest PCV and GCV was recorded for kernel breadth. Therefore, selection on the basis of phenotypic expression alone cannot be effective for the improvement of these traits. Similar opinion was expressed by Pathak and Sharma (1996), Sarvanan and Senthil (1997), Rather et al. (1998), Satya Priya Lalitha and Sreedhar (1999), Shivani and Reddy (2000), Iftekharudduala et al. (2001) and Sao (2002). Studies of variation indicated that the estimates of PCV were slightly higher than the corresponding GCV estimates for all the traits studied except panicle length and kernel elongation ratio. The estimates of heritability act as predictive instrument in expressing the reliability of phenotypic value. Therefore, high heritability helps in effective selection for a particular character. Among the yield characters, highest heritability was registered for days to 50% flowering, kernel length and kernel L/B ratio, whereas kernel breadth had lowest heritability. Similar results have been reported by Panwar et al. (1997), Sarawgi et al. (2000), Gannamani (2001) and Sao (2002). The genetic advance is a useful indicator of the progress that can be expected as result of exercising selection on the pertinent population. Heritability in conjunction with genetic advance would give a more reliable index of selection value (Johnson et al. 1955). Genetic advance was highest for number of filled grains per panicle followed by plant height and lowest for panicle length among yield characters. In case of grain quality characters, head rice recovery recorded highest genetic advance and the lowest for kernel breadth. The genetic advance as per cent of mean was highest in case of number of filled grains/panicle followed by grain yield per plant, while it was low in case of days to 50% flowering. Whereas, with respect to grain quality characters, head rice recovery registered the highest genetic advance as per cent mean and the lowest value was associated with kernel breadth. (Regina et al. 1994, Vanniarajan et al. 1996, Shivani and Reddy 2000, Iftekharudduala et al. 2001, Gannamani, 2001 and Sao, 2002).

157 In general, the characters that show high heritability with high genetic advance are controlled by additive gene action (Panse and Sukhatme, 1957) and can be improved through simple or progeny selection methods. Selection for the traits having high heritability coupled with high genetic advance would accumulate more additive genes leading to further improvement of their performance. In the present study, high heritability along with medium to high genetic advance was noticed for the traits, days to 50% flowering, 1000 grain weight and most of the kernel traits. These characters with high heritability, moderate genetic advance can be improved by direct selection and inter-mating superior genotypes in segregating population (F 2 ) developed from recombination breeding (Samadia, 2005) F 3 GENERATION Days to 50% flowering A mean of 98 days, range from 82 (RNR 2354 x Basmati 370) to 114 (BPT 5204 x Akshyadhan) days between the entries was recorded for this trait (Table 4.60). This trait had low variability of 8.14 (PCV) and 7.87 (GCV) with high heritability (broad sense) of 94 per cent and genetic advance as per cent of mean was moderate (20.09). Moderate GCV, PCV, high heritability and moderate genetic advance for days to 50% flowering were reported by Ahmed et al. (2010) and Manoj Kumar Prajapati et al. (2011) as in the present study (Table 4.61) Plant height Plant height is mostly governed by genetic makeup of the genotypes, but the environmental factors also influence it (Ashrafuzzaman et al. 2009) and the range for this character was from 61 to 127 cm with a mean of 101cm (Table 4.41). The phenotypic coefficient of variation (14.86) was also higher than genotypic coefficient of variation (12.97). The character showed moderate phenotypic and genotypic coefficient of variation, high heritability (76), high genetic advance (30.18) and high genetic advance as percentage of mean (29.87 per cent) indicating the governance of additive genes for this character. Similar result was found by Okelola et al.(2007) Ahmed et al. (2010) and Ullah et al. (2011) reported moderate GCV and PCV, high heritability and high genetic advance as percentage of mean for this trait whereas, Chakraborty and Chakraborty (2010) revealed moderate GCV and PCV, high heritability and moderate genetic advance as percentage of mean for this trait.

158 Number of productive tillers per plant Tiller trait in rice is a major determinant of panicle production, thus the total yield in rice. The genotypes, which produced higher number of effective tillers per plant showed higher grain yield in rice (Dutta et al. 2002). Productive tillers per plant showed moderate PCV (18.93) and GCV (16.06) with high heritability of 72 per cent and high genetic advance as per cent mean. The range for number of productive tillers per plant was from 11.8 (BPT 5204 x NLR 145) to 22.7 (Pusa 1121 x Basmati 370) with a mean of The PCV was higher than corresponding GCV in this trait which implies that this trait was influenced by environment. Anbanandan et al. (2009), Ahmed et al. (2010) and Manoj Kumar Prajapati et al. (2011) reported high heritability and high genetic advance as percentage of mean for this trait, whereas Bisne et al. (2009) reported moderate heritability for this trait as in the case of present investigation Panicle length Lowest panicle length of 18.7 cm was recorded in the cross BPT 5204 x Sumathi, whereas it was highest mean in case of Akshyadhan x Sumathi (27.2 cm) and the mean was 24.1 cm. Panicle length showed low genotypic (8.51) and phenotypic (9.36) coefficients of variation, high heritability (83), low genetic advance (4.92 per cent) which was in accordance with the findings of Vange et al. (1999), Bisne et al. (2009) and Manoj Kumar Prajapati et al. (2011) Panicle weight The mean values ranged from 0.4 (Pusa 1121 x Basmati 370) to 2.3 g. (BPT 5204 x Akshyadhan) with a mean of 1.6 g. High GCV and PCV recorded was and per cent respectively. The high heritability of 86 per cent and high genetic advance as per cent mean of per cent was observed for this trait. This trait showed high GCV (21.44), PCV (23.07), high heritability (86 per cent) and high genetic advance as percentage of mean (52.61) indicating the suitability of the trait as selection index in plant improvement program. The phenotypic coefficient of variation was higher than corresponding genotypic coefficient of variation, implying the influence of environment on the expression of the trait. It revealed that the genotypic variation contribute maximum to phenotypic variation and the environmental deviation had minor contribution for the trait. Ali et al. (2000) observed Moderate variability, high heritability and high genetic advance as percentage of mean and

159 Ahmed et al. (2010) reported low GCV and PCV, moderate heritability and low genetic advance as percentage of mean for panicle weight per plant Number of filled grains per panicle Number of filled grains/panicle is the most important yield contributing character in rice. According to Dutta et al. (2002) genotypes which produced higher number of grains per panicle showed higher grain yield in rice. The range was very low i.e 11 (Pusa 1121 x Basmati 370) to high 130 (BPT 5204 x RNR 2354) with a mean of 75 filled grains per panicle. Coefficients of variability at phenotypic (35.73 per cent) and genotypic (35.10 per cent) levels were high for the character indicating apparent variation among the genotypes for this trait. Estimates of heritability (97.0), genetic advance (68.71) and genetic advance as percentage of mean (91.02) were high for this trait indicating the role of additive gene action and hence can be improved through simple selection methods (Vange 2009, Manoj Kumar Prajapati et al and Singh et al. 2011) grain weight The range for this character was from to g with a mean value of g. Moderate PCV and GCV were recorded with estimates of and per cent respectively. High heritability (90 per cent) coupled with high genetic advance as per cent of mean (39.20 per cent) was observed for this character. Hasib et al. (2005) reported moderate GCV and PCV, high heritability and high genetic advance as percentage of mean for this trait. Anbanandan et al. (2009) observed high heritability and high genetic advance and Kumar et al. (2009) revealed high heritability for this trait. On the other hand Lal and Chauhan (2011) reported moderate GCV and PCV and high genetic advance as percentage of mean. High heritability coupled with high genetic advance indicated that, grain weight was largely influenced by additive gene effects hence, direct selection for this yield component would be much rewarding Grain yield per plant The trait grain yield per plant had mean value of 18.5 g. with the range of 10.8 (RNR 2354 x Sumathi) to 26.7 g (BPT 5204 x RNR 2354) (Table 4.40). Whereas, genotypic and phenotypic coefficients of variation were per cent and per cent respectively. Moderate heritability (77 per cent) and high genetic advance as percentage mean (44.76) were registered for this trait (Table 4.60).

160 Presence of wide gap between PCV and GCV indicated the predominant role of environment in the expression of the trait which is in consonance with the results obtained by several workers viz., Hasib et al. (2005), Anbanandan et al. (2009), Vange (2009) and Ahmadikhah et al. (2010). The estimates of heritability and genetic advance as percentage of means were moderate for this trait suggesting preponderance of both additive and non-additive gene actions in expression of this character (Anbanandan et al. 2009, Bisne et al and Vange, 2009). As such selection of superior plant in early generations and intermating them to pooling positive genes would be a perspective breeding method for yield improvement in rice Kernel length (mm) The mean for kernel length was 5.95 mm, whereas the range was from 4.81 mm (BPT 5204 x Basmati 370) to 7.10 mm (Pusa 1121 x Sumathi). A low to moderate PCV (9.83) and GCV (8.28) coupled with high heritability (71) and moderate genetic advance as per cent of mean (18.39) was registered for this trait as was reported by Bharadwaj et al. (2007) and Krishna et al. (2008) Kernel breadth (mm) The range for this character was very high i.e from 1.47 mm (BPT 5204 x Basmati 370) to 2.00 mm (Akshyadhan x NLR 145) with a mean value of 1.63 mm. The PCV and GCV estimates were 7.80 and 6.30 per cent respectively. High heritability (65 per cent) coupled with low genetic advance (0.22 per cent) was observed for this character which is in agreement with the findings of Ravindra babu et al. (2012), Pawan Saini et al. (2013) and Rajesh Kumar Dhanwani et al.(2013) Kernel L/B ratio Moderate PCV (11.54 per cent) and GCV (9.96 per cent) with high heritability (75.0) and genetic advance as per cent mean (22.68) observed for this character indicated a good scope for pedigree selection for further improvement of this important trait. Further, the range (2.80 to 4.60) was also very high (Nayak et al and Rajesh Kumar Dhanwani et al. 2013) Kernel length after cooking (mm) The mean values ranged from 7.75 nm (BPT 5204 x Basmati 370) to 13.0 mm (Pusa 1121 x Improved Pusa Basmati) with a mean of 9.51 mm. Moderate PCV and GCV were recorded. The high heritability (77.0) and high genetic advance as per cent mean (27.34) were observed for this trait (Rajesh Kumar Dhanwani et al. 2013).

161 Kernel elongation ratio Among the cooking quality characters, this quality character occupies a prime place. The trait registered a mean value of 1.60 with the range of 1.46 to 1.85 and genotypic phenotypic coefficients of variation were 4.75 and 7.23 per cent respectively. Low heritability (43 per cent) along with low genetic advance as percentage mean (8.23) indicated less scope for direct selection (Venkata Subbaiah et al. 2011) Head rice recovery per cent The observed range was from (RNR 2354 x Basmati 370) to per cent (NLR 145 x RNR 2354) while the mean value reported for this trait was per cent. The GCV (11.62 per cent) and PCV (14.27 per cent) and heritability (66 per cent) were moderate to low (Vanisree et al. 2013). In the present study, the phenotypic and genotypic coefficients of variation computed to assess the nature and magnitude of existing variability in the F 3 population, reveled presence of higher magnitudes of PCV and GCV with respect to number of filled grains/panicle and panicle weight. This indicated greater scope of obtaining high selection response for these traits. These results are in conformity with the findings of earlier workers viz., Pandey et al. (2009) and Yadav et al. (2011). The moderate estimates of Coefficient of Variation at genotypic level were observed for plant height, number of productive tillers/plant, 1000 grain weight, grain yield, kernel length after cooking and head rice recovery, as such these traits are likely to permit limited direct selection. Singh et al. (2008) found moderate PCV and GCV estimates for grain yield per plant and number of productive tillers/plant. Low estimates of PCV and GCV were observed for days to 50% flowering, plant height, panicle length, kernel length, kernel breadth and kernel elongation ratio. Khedikar et al. (2004) also reported low estimates of genotypic and phenotypic coefficients with respect to days to 50% flowering and plant height. The occurrence of low estimates of genotypic and phenotypic coefficients of variation indicated that further selection directly based on these parameters would not be much rewarding. Among the characters studied, high estimates of heritability in broad sense with high genetic advance in percentage of mean were observed in general for most of the characters including grain dimensions whereas, in case of others, kernel length after cooking and head rice recovery the values were low. High estimates of heritability with high genetic advance in percent of mean have also been reported earlier for grain yield

162 per plant (Bagheri et al. 2008; Sarangi et al. 2009), number of filled grains/panicle (Suman et al. 2005, Devi et al. 2006) and for number of grains per panicle (Anjaneyulu et al. 2010). The traits viz., plant height, number of productive tillers/plant, panicle weight, 1000 grain weight and grain yield per plant also showed moderate to low heritability and genetic advance which suggested that inter mating of segregating genotypes to accumulate plus genes may provide very high response to selection for further improvement. The high estimates of heritability with moderate genetic advance were recorded for the yield components viz., panicle length, filled grains per panicle and 1000 grain weight and kernel traits viz., kernel length and L/B ratio, which suggested that additive genetic effects played greater role as such, the chances of obtaining desirable segregants with good yield potential and quality are very bright through direct selection. However, for kernel elongation ratio and head rice recovery direct selection may not be much useful due low heritability coupled with low to medium genetic advance as percent mean CROSSWISE GENETIC PARAMETERS IN 11 CROSSES The discussions made under sections and was pertaining to the genetic parameters estimated treating F 2 and F 3 generations as two different populations. Selection from F 2 generation onwards will be very effective when the heritability and genetic advance estimates are based on additive gene effects. As the back crosses are not available in the present study, the inbreeding depression was taken as one criteria to judge the presence of additive genetic variation. The population/ character with high heterosis and less inbreeding depression are considered to be under the control of additive gene effects (Pundhan singh and Narayanan, 2009). Underlining this, 11 crosses with high per se performance, heterosis coupled with less inbreeding depression were carefully choosen and genetic parameters viz., GCV, PCV, h 2 (ns) and GA were estimated to suggest suitable breeding methods (Table. 4.62). Among the four crosses, Sumathi x Basmati 370 registered as better one for selection of dwarf genotypes owing to presence of high coefficient of variation, heritability and genetic advance. The cross which exhibited superior performance for yield and its components had poor expression for quality traits and vice versa. Keeping in view a good amount of variability, high estimates of heritability and expected genetic

163 advance, direct selection for yield improvement in two crosses viz., Sumathi x Basmati 370 and Akshyadhan x NLR 145 and for quality improvement in five crosses viz., NLR 145 x Pusa 1121, Pusa 1121 x Sumathi, Pusa 1121 x Improved Pusa Basmati, Sumathi x Improved Pusa Basmati and Improved Pusa Basmati x Basmati 370 was considered as highly feasible and recommended. However, direct selection for kernel elongation ratio with respect to only one cross (Sumathi x Improved Pusa Basmati) may not be much rewarding due to low heritable variation.

164 4.6 CHARACTER ASSOCIATION AND PATH COEFFICIENT ANALYSIS IN F 1, F 2 and F 3 GENERATIONS Character Association Data on fourteen characters viz., days to 50 per cent flowering, plant height, number of productive tillers per plant, panicle length, panicle weight per plant, number of filled grains per panicle, 1000 grain weight, grain yield per plant, kernel length, kernel breadth and kernel L/B ratio obtained from 28 F 1 s, F 2 s and F 3 s evaluated in diallel set (without reciprocals) were subjected to correlation analysis. The estimates of simple correlation coefficients between yield per plant and its components and among the component characters themselves were tested for their significance and results are presented in Table Grain yield per plant registered positive and significant association with panicle weight over the three generations (F 1, F 2 and F 3 ) and plant height and panicle length in F 1 generation and days to 50% flowering and number of filled grains/panicle in both F 1 and F 2 generations. A negative and significant association was observed between grain yield per plant and kernel length and kernel L/B ratio in all the three generations. Similar results were reported by Madhavilatha (2002), Krishna et al. (2008), Immanuel Selvaraj et al. (2011) and Rafii et al. (2014) for plant height; Babar et al. (2007), Immanuel Selvaraj et al. (2011), Basavaraja et al. (2011), Shanthi et al. (2011) and Rafii et al. (2014) for number of productive tillers/plant; Prasad et al. (2001), Akhtar et al. (2011), Immanuel Selvaraj et al. (2011) and Gulzar et al. (2012) for number of filled grains/panicle and Prasad et al. (2001), Akhtar et al. (2011) for days to 50% flowering. The character days to 50 per cent flowering exhibited significant positive association in F 2 and F 3 generations with grain yield per plant, as was reported by Sakthivel (2001), Madhavilatha (2002), Suman (2003), Kuldeep et al. (2004), Vinothini and Ananda Kumar (2005) and Krishna et al. (2008). Non significant association, however, was reported by Krishna Naik et al. (2005), Swain and Reddy (2006) and Sharma and Sharma (2007). It also expressed positive significant association with number of filled grains/panicle in F 2 and F 3 generations. A negative significant association was observed between this trait and panicle length, plant height, 1000 grain

165 weight, kernel length and kernel L/B ratio in all the three generations. These results are in conformity with the results of Ravindra babu et al. (2012) for number of productive tillers/plant; Nayak et al. (2001), Krishnaveni and Shobha Rani (2006), Krishna et al. (2008) and Venkanna et al. (2014) for 1000 grain weight; Krishna et al. (2008) and Venkanna et al. (2014) for kernel length and Krishna Naik et al. (2005) and Venkanna et al. (2014) for kernel L/B ratio. Increased flowering duration resulted in increase of panicle weight and number of filled grains per panicle, which intern helped to realize higher grain yield per plant. In all the three generations (F 1, F 2 and F 3 ), plant height had negative association with number of grains per panicle and productive tillers/plant, but a positive association with panicle length, 1000 grain weight and kernel length and breadth. Further a positive association between plant height and panicle length and also grain yield was observed only in case of F 1 generation. These relations clearly indicated that plant height plays greater role in enhancement of yield potential in rice. Thus, breeding for semi tall varieties with sturdy culm rather than dwarf varieties would be a perspective approach. Yogameenakshi et al. (2004), Krishna Naik et al. (2005), Panwar and Mashiat Ali (2007) and Krishna et al. (2008) reported a positive correlation between grain yield and plant height where as Venkanna et al. (2014) reported a similar association with kernel length and breadth as in the case of present study. It appears that number of ear bearing tillers has no correlation with grain yield in case of aromatic rice. This trait infact exhibited negative correlation with other important components like grains per panicle and panicle weight (Chaubey and Richharia, 1993; Tara Satyavathi et al. 2001, Krishna Naik et al and Venkanna et al. 2014). In contrary to present studies, this character, had significant positive association with panicle weight, number of filled grains/panicle, 1000 grain weight as per the reports of Borbora et al. (2005), Swain and Reddy (2006), Sharma and Sharma (2007) and Krishna et al. (2008). Panicle length recorded positive and significant association with number of filled grains/panicle in F 1 generation but a negative and significant association in F 3 generation. This trait is considered as an important component for realizing high yield, because it exhibited significant and positive association with kernel length, kernel L/B ratio (Krishna et al and Venkanna et al. 2014) besides with panicle weight. The trait, panicle weight exhibited positive and significant correlation with grain yield in all the generations. Further, this trait had significant and positive associations

166 with number of filled grains/panicle, kernel breadth and plant height. Significant and negative association was observed with number of productive tillers/plant, kernel length and kernel L/B ratio. Positive and significant correlation of panicle weight with filled grains for panicle (Swain and Reddy, 2006), 1000 grain weight (Sudharani et al. 2014), kernel breadth (Venkanna et al. 2014) and grain yield (Swain et al and Reddy, 2006) was also reported earlier as in the case of present study. The character, filled grains per panicle exhibited positive and significant association with grain yield per plant in F 2 as well as in F 3 generations, however, in F 1 it was not significant (Eradasappa et al. 2007b, Panwar and Mashiat Ali, 2007, Sharma and Sharma, 2007, Anbumalarmathi and Nadarajan, 2008 and Krishna et al. 2008). In all the three generations, number of filled grains/panicle possessed a strong negative correlation with productive tillers per plant. Negative significant association was observed between this trait and kernel length (Krishna Veni and Shobha Rani, 2006, Krishna et al and Venkanna et al. 2014) and kernel L/B ratio (Krishna et al. 2008) however, it was positive in F 1 generation. No significant association was observed between 1000 grain weight and grain yield per plant, however, had positive significant association with kernel length (Krishna et al. 2008, Nivedhitha et al and Venkanna et al. 2014) and kernel breadth (Krishna Veni and Shobha Rani, 2006 and Krishna et al. 2008) in all the three generations (F 1, F 2 and F 3 ) and kernel L/B ratio (Krishna et al and Venkanna et al. 2014) in F 2 generation. Significant and negative association was observed between kernel length and grain yield in F 1, F 2 and F 3 generations (Krishna Veni and Shobha Rani, 2006, Krishna et al. 2008, Nivedhitha et al. 2013), however this trait, exhibited strong positive association with panicle length, 1000 grain weight (Nayak et al. 2001, Madhavi Latha et al. 2005) and kernel L/B ratio (Krishna et al. 2008, Nivedhitha et al and Venkanna et al, 2014). Kernel breadth had a positive correlation with grain yield per plant, but not significantly (Reddy et al and Madhavi Latha et al. 2005). The strong association between kernel breadth and panicle weight indicated that bold grains helped increase yield to larger extent. The trait, kernel L/B ratio found to possess negative and significant association with grain yield per plant irrespective of generations as in the case of kernel length

167 (Krishna Naik et al. 2005, Krishna Veni and Shobha Rani, 2006 and Krishna et al. 2008). This particular component had a good positive correlation with panicle and kernel length. A critical observation of kernel characters indicated that, yield potential in rice is related to boldness rather than slenderness. These studies finally indicated that there is change in the association between the yield components by changing the generation and among the different yield components, panicle weight and number of filled grains are very crucial for higher yields, as they exhibited significant positive correlations with grain yield/ plant in all the generations. The next important traits to be considered are plant height and panicle length. Many times, in rice, semi tall plant types ( cm) with sturdy culm (non lodging) would yield better than the dwarf ones. Further, it has been observed that breadth had positive correlation with grain yield indicating bold grained varieties have more potential and slenderness appears to be a yield constraint in rice Path Coefficient Analysis Based on the data recorded on 28 F 1 s, F 2 s and F 3 s, the correlations were employed to determine the direct and indirect effects of yield components on grain yield and grain characteristics in rice. The results are presented in Table Days to 50% flowering had positive direct effect (0.0482) on grain yield in F 3 generation only. Positive low level of indirect effect was exerted on grain yield per plant by days to 50% flowering through plant height, panicle length, 1000 grain weight, kernel length and kernel L/B ratio in F 1 and F 2 generations and panicle weight positively in F 3 generation and kernel breadth positively in all the three generations (F 1, F 2 and F 3 ) and number of filled grains/panicle positively in F 1 and F 3 generations and negatively in F 2 generation. Days to 50% flowering had the indirect negative effect on grain yield through number of productive tillers/plant in all the three generations (F 1, F 2 and F 3 ) and plant height, panicle length, 1000 grain weight, kernel length and kernel L/B ratio in F 3 generation. Plant height had positive direct effect ( and ) on grain yield in F 1 and F 3 generations only. Indirect positive influence of plant height on grain yield was observed through panicle length, panicle weight, 1000 grain weight, kernel length and kernel breadth in F 1 and F 3 generations and negative influence in F 2 generation.

168 Panicle length exhibited positive direct effect (0.0030) on grain yield in F 3 generation only. Positive low level of indirect effect was exerted on grain yield by panicle length through days to 50% flowering in F 1 and F 2 generations and negatively in F 3 generation. One interesting thing is that the trait number of productive tillers/plant exhibited positive effect (0.4922, and ) on economic yield in all the three F 1, F 2 and F 3 generations. Positive direct effect of number of productive tillers/plant on yield in the present study is in conformity with the results of Krishna et al. (2008), Satish Chandra et al. (2009), Supriyo Chakraborty et al. (2010), Ravindra babu et al. (2012), Awaneet Kumar and Senapathi (2013), Imad Naseem et al (2014) and Tirumala Rao et al. (2014). It exhibited mostly negative indirect effects through other yield components in all generations except in F 3 including through kernel length and kernel L/B ratio. Panicle weight had the highest positive direct effect on economic yield (0.8868, and ) in all the three generations (F 1, F 2 and F 3 ). These results are in agreement with the earlier reports of Awaneet Kumar and Senapathi (2013) and Sarker et al. (2013).This trait also had positive indirect effect via days to 50% flowering, plant height, panicle length, number of filled grains/panicle and kernel breadth in all the three generations, 1000 grain weight in F 2 generation. Whereas negative indirect effect was observed through number of productive tillers/plant, kernel length and kernel L/B ratio in all the three generations and 1000 grain weight in F 1 and F 3 generations. Number of filled grains/panicle had direct positive effect of , , in F 1, F 2 and F 3 generations respectively on grain yield as was reported by Suman et al. (2006), Krishna et al.(2008), Satish Chandra et al. (2009), Jayasudha and Sharma (2010), Nandan et al. (2010), Yadav et al. (2010), Satheesh kumar and Saravanan (2012), Seyoum et al. (2012), Tirumala Rao et al. (2014) and Venkanna et al. (2014). The component, 1000 grain weight exhibited negative direct effect ( and ) in F 1 and F 3 generations and positive effect (0.2848) in F 2 generations on grain yield per plant. Indirect positive influence of 1000 grain weight on grain yield was observed through plant height (Immanuel Selvaraj et al. 2011, Imad Naseem et al and Tirumala Rao et al. 2014), panicle length (Ravindra babu et al. 2012, Imad Naseem et al and Tirumala Rao et al. 2014), kernel length (Reddy et al and Krishna

169 et al. 2008), kernel breadth (Madhavilatha, 2002 and Krishna et al. 2008) and kernel L/B ratio (Krishna et al and Awaneet Kumar and Senapathi 2013) in F 2 generation, number of filled grains/panicle in F 3 generation and days to 50% flowering in F 1 and F 3 generations and panicle weight in all the three generations. Whereas negative indirect effect was observed on yield through number of productive tillers/plant in all the three generations (Supriyo Chakraborty et al. 2010, Immanuel Selvaraj et al and Tirumala Rao et al. 2014). The trait kernel length exhibited negative effect ( , ) on economic yield in F 1 and F 2 generations and positive effect (1.3280) in F 3 generation. It indirectly contributed positively to yield through number of productive tillers/plant in F 1, F 2 and F 3 generations and number of filled grains/panicle in F 2 generation and days to 50% flowering and panicle weight in F 1 and F 2 generations. Similar results were reported by Tara Satyavathi et al. (2001) for number of productive tillers/plant and number of filled grains/panicle; Krishna et al. (2008) for days to 50% flowering and Awaneet Kumar and Senapathi (2013) and Venkanna et al. (2014) for panicle weight. Indirect negative influence of kernel L/B ratio on grain yield was observed through number of productive tillers/plant in all the three generations and days to 50% flowering, panicle weight and kernel breadth F 1 and F 2 generations. Kernel breadth and kernel L/B ratio showed positive direct effect on grain yield in F 1 and F 2 generations. Kernel breadth exhibited positive indirect effect on grain yield through plant height (Awaneet Kumar and Senapathi, 2013), panicle weight, number of filled grains/panicle (Madhavilatha, 2002), 1000 grain weight (Awaneet Kumar and Senapathi, 2013) and kernel length (Krishna et al. 2008) and kernel L/B ratio exhibited indirect effect through panicle length (Krishna et al. 2008), 1000 grain weight (Awaneet Kumar and Senapathi, 2013) and kernel length (Krishna et al. 2008). A critical analysis of both character association and path analysis indicated that among the yield components investigated, panicle weight and number of filled grains/panicle are very important, as the correlation coefficients as well the direct effects were high irrespective of the generation. Another important character to be considered for high yield is panicle length, because when the length of panicle is high, the grains will be placed loosely and good grain filling is achieved with high test weight and less chalkiness.

170 Table 4.1. Analysis of variance for grain yield, yield contributing characters and grain quality characteristics in aromatic rice Source of variation d.f. Days to 50 % flowering Plant height (cm) Number of productive tillers/ plant Panicle length (cm) Panicle weight (g) Number of filled grains/ panicle 1000 grain weight (g) Replications Treatments ** ** ** ** ** ** ** Error Total Cont.

171 Table 4.1 (Cont.). Analysis of variance for grain yield, yield contributing characters and grain quality characteristics in aromatic rice Source of variation d.f. Grain yield/ plant (g) Kernel length (mm) Kernel breadth (mm) Kernel l/b ratio Kernel length after cooking (mm) Kernel elongation ratio Head rice recovery (%) Replications ** 0.04 ** 2.64 Treatments ** 1.25 ** 0.02 ** 0.42 ** 5.75 ** 0.14 ** ** Error Total *Significant at 5 % level, ** Significant at 1 % level

172 Table 4.2. Mean performance of parents and crosses for fourteen characters Genotype Days to 50 % flowering Plant height (cm) Number of productive tillers/ plant Panicle length (cm) Panicle weight (g) Number of filled grains/ panicle 1000 grain weight (g) Grain yield/ plant (g) Kernel length (mm) Kernel breadth (mm) Kernel l/b ratio Kernel length after cooking (mm) Kernel elongation ratio Parents (8) BPT Akshyadhan NLR Pusa RNR Sumathi Improved Pusa Basmati Basmati Mean (Parents) Head rice recovery (%) Cont.

173 Table 4.2 (Cont.) Genotype Days to 50 % flowering Plant height (cm) Number of productive tillers/ plant Panicle length (cm) Panicle weight (g) Number of filled grains/ panicle 1000 grain weight (g) Grain yield/ plant (g) Kernel length (mm) Kernel breadth (mm) Kernel l/b ratio Kernel length after cooking (mm) Kernel elongation ratio F 1 (28 Crosses) BPT 5204 x Akshyadhan BPT 5204 x NLR BPT 5204 x Pusa BPT 5204 x RNR BPT 5204 x Sumathi BPT 5204 x I.P. Basmati BPT 5204 x Basmati Akshyadhan x NLR Akshyadhan x Pusa Akshyadhan x RNR Akshyadhan x Sumathi Akshyadhan x I.P. Basmati Akshyadhan x Basmati NLR 145 x Pusa NLR 145 x RNR NLR 145 x Sumathi NLR 145 x I.P. Basmati NLR 145 x Basmati Pusa 1121 x RNR Pusa 1121 x Sumathi Pusa 1121 x I.P. Basmati Pusa 1121 x Basmati RNR 2354 x Sumathi RNR 2354 x I.P. Basmati RNR 2354 x Basmati Sumathi x I.P. Basmati Sumathi x Basmati I.P. Basmati x Basmati Mean (F 1) Cont. Head rice recovery (%)

174 Table 4.2 (Cont.) Genotype Days to 50 % flowering Plant height (cm) Number of productive tillers/ plant Panicle length (cm) Panicle weight (g) Number of filled grains/ panicle 1000 grain weight (g) Grain yield/ plant (g) Kernel length (mm) Kernel breadth (mm) Kernel l/b ratio Kernel length after cooking (mm) Kernel elongation ratio F 2 (28 Crosses) BPT 5204 x Akshyadhan BPT 5204 x NLR BPT 5204 x Pusa BPT 5204 x RNR BPT 5204 x Sumathi BPT 5204 x I.P. Basmati BPT 5204 x Basmati Akshyadhan x NLR Akshyadhan x Pusa Akshyadhan x RNR Akshyadhan x Sumathi Akshyadhan x I.P. Basmati Akshyadhan x Basmati NLR 145 x Pusa NLR 145 x RNR NLR 145 x Sumathi NLR 145 x I.P. Basmati NLR 145 x Basmati Pusa 1121 x RNR Pusa 1121 x Sumathi Pusa 1121 x I.P. Basmati Cont. Head rice recovery (%)

175 Table 4.2 (Cont.). Genotype Days to 50 % flowering Plant height (cm) Number of productive tillers/ plant Panicle length (cm) Panicle weight (g) Number of filled grains/ panicle 1000 grain weight (g) Grain yield/ plant (g) Kernel length (mm) Kernel breadth (mm) Kernel l/b ratio Kernel length after cooking (mm) Kernel elongation ratio Pusa 1121 x Basmati RNR 2354 x Sumathi RNR 2354 x I.P. Basmati RNR 2354 x Basmati Sumathi x I.P. Basmati Sumathi x Basmati I.P. Basmati x Basmati Mean (F 2 ) Check (2 varieties) MTU Pusa General Mean C.V (%) SE(d) C.D (5%) I.P.Basmati : Improved Pusa Basmati Head rice recovery (%)

176 Table 4.3. Estimation of heterosis over mid parent, better parent, standard heterosis and inbreeding depression for days to 50 per cent flowering, plant height and number of productive tillers/plant. Crosses Days to 50% flowering Plant height (cm) Number of productive tillers/plant Mean MP BP SH (Y) ID Mean MP BP SH (Y) ID Mean MP BP SH (Y) ID BPT 5204 x Akshyadhan ** ** 2.30 * ** ** ** ** ** ** BPT 5204 x NLR ** ** ** ** ** ** ** BPT 5204 x Pusa ** ** ** ** ** ** ** ** ** BPT 5204 x RNR * 4.72 ** 9.18 ** ** ** ** ** * BPT 5204 x Sumathi ** ** ** ** ** ** * ** ** BPT 5204 x I.P. Basmati ** ** ** 9.75 ** ** * ** ** BPT 5204 x Basmati * 2.31 * ** ** ** ** ** ** ** Akshyadhan x NLR ** ** * ** ** ** ** ** ** ** ** Akshyadhan x Pusa ** ** ** ** * ** * ** ** ** Akshyadhan x RNR ** ** ** ** ** ** ** ** ** * ** Akshyadhan x Sumathi ** ** ** ** ** ** ** Akshyadhan x I.P. Basmati ** ** ** ** ** ** ** ** ** ** * Akshyadhan x Basmati ** * ** ** ** 8.64 ** ** NLR 145 x Pusa ** ** ** ** ** ** ** * NLR 145 x RNR ** ** ** * ** ** NLR 145 x Sumathi ** ** * ** ** ** 5.48 ** * * NLR 145 x I.P. Basmati ** ** ** ** ** ** * NLR 145 x Basmati ** ** * ** ** ** ** * Pusa 1121 x RNR ** ** ** ** 7.07 ** ** ** ** ** ** ** Pusa 1121 x Sumathi ** ** ** ** ** ** ** ** ** ** Pusa 1121 x I.P. Basmati ** ** ** ** ** ** ** * ** ** ** ** Pusa 1121 x Basmati ** ** ** ** ** ** ** * ** ** 0.69 RNR 2354 x Sumathi ** ** ** ** ** ** ** ** RNR 2354 x I.P. Basmati ** ** ** ** ** ** ** 6.29 * ** ** ** ** RNR 2354 x Basmati ** * ** * ** 6.45 ** * * Sumathi x I.P. Basmati ** ** ** ** ** ** ** ** Sumathi x Basmati ** ** ** ** ** ** * I.P. Basmati x Basmati ** ** ** ** ** ** ** ** * * * Significant at 5 % level, ** Significant at 1 % level MP: Heterosis over mid parent; BP: Heterosis over better parent; SH (Y): Standard heterosis for yield on MTU 1010; ID: Inbreeding depression.

177 Table 4.4. Estimation of heterosis over mid parent, better parent, standard heterosis and inbreeding depression for panicle length, panicle weight and number of filled grains/panicle. Crosses Panicle length (cm) Panicle weight (g) Number of filled grains/panicle Mean MP BP SH (Y) ID Mean MP BP SH (Y) ID Mean MP BP SH (Y) ID BPT 5204 x Akshyadhan ** * ** 9.35 ** ** ** ** ** ** ** ** BPT 5204 x NLR * * ** ** BPT 5204 x Pusa ** ** ** ** ** ** ** ** ** BPT 5204 x RNR ** ** * ** * * * * BPT 5204 x Sumathi ** ** 9.20 * ** ** * * * * ** BPT 5204 x I.P. Basmati * * ** ** * * ** BPT 5204 x Basmati ** ** ** * * ** * ** ** Akshyadhan x NLR * ** 7.76 ** * ** * ** Akshyadhan x Pusa ** ** ** ** * ** ** * Akshyadhan x RNR ** ** ** * ** ** ** Akshyadhan x Sumathi ** ** 8.27 ** ** ** ** * ** Akshyadhan x I.P. Basmati ** ** ** * ** * ** ** Akshyadhan x Basmati * ** * * * ** NLR 145 x Pusa ** ** ** ** ** ** * ** ** ** NLR 145 x RNR * ** ** * * NLR 145 x Sumathi * ** ** * ** ** * ** NLR 145 x I.P. Basmati ** ** * ** ** ** ** NLR 145 x Basmati ** ** 9.05 * * ** ** Pusa 1121 x RNR ** ** ** ** * ** ** Pusa 1121 x Sumathi ** ** ** ** ** * ** ** ** ** Pusa 1121 x I.P. Basmati * ** ** ** ** ** ** Pusa 1121 x Basmati * ** ** ** ** ** RNR 2354 x Sumathi ** ** ** ** ** ** ** ** ** ** ** ** RNR 2354 x I.P. Basmati ** ** 7.68 ** ** ** ** ** ** ** ** RNR 2354 x Basmati * ** ** ** ** ** ** Sumathi x I.P. Basmati ** ** ** ** ** ** ** ** ** ** * ** Sumathi x Basmati ** ** * ** ** ** * I.P. Basmati x Basmati ** ** ** ** ** ** * Significant at 5 % level, ** Significant at 1 % level MP: Heterosis over mid parent; BP: Heterosis over better parent; SH (Y): Standard heterosis for yield on MTU 1010; ID: Inbreeding depression.

178 Table 4.5. Estimation of heterosis over mid parent, better parent, standard heterosis and inbreeding depression for 1000 grain weight, grain yield/plant and kernel length Crosses 1000 grain weight (g) Grain yield/plant (g) Kernel Length (mm) Mean MP BP SH (Y) ID Mean MP BP SH (Y) ID Mean MP BP SH (Q) ID BPT 5204 x Akshyadhan ** ** ** ** ** ** ** ** 1.01 BPT 5204 x NLR * ** ** * ** ** * ** ** * BPT 5204 x Pusa ** ** ** ** ** ** ** ** ** 3.52 ** BPT 5204 x RNR * ** ** ** ** ** ** BPT 5204 x Sumathi ** ** ** ** ** ** ** ** * ** BPT 5204 x I.P. Basmati ** ** ** * ** ** ** BPT 5204 x Basmati ** ** ** ** * * ** ** ** ** Akshyadhan x NLR ** ** 6.51 ** ** * ** 9.46 ** ** 6.69 * Akshyadhan x Pusa ** ** ** ** * ** * ** ** 5.38 * Akshyadhan x RNR ** ** ** ** ** ** ** ** Akshyadhan x Sumathi ** ** ** ** * ** ** 8.88 * Akshyadhan x I.P. Basmati ** ** 7.34 ** ** ** ** ** 3.66 * * ** Akshyadhan x Basmati * ** * ** ** 8.27 NLR 145 x Pusa ** ** ** ** ** ** * ** ** ** 8.66 * NLR 145 x RNR ** 8.92 ** ** * * ** 4.93 * ** 5.26 * NLR 145 x Sumathi ** 7.57 ** 5.99 ** ** ** * ** * ** ** 3.88 NLR 145 x I.P. Basmati ** ** ** ** * ** ** 8.95 ** NLR 145 x Basmati ** 5.50 * ** ** ** Pusa 1121 x RNR ** ** * ** * ** ** 7.98 ** Pusa 1121 x Sumathi ** 5.98 ** ** ** ** ** ** ** ** ** Pusa 1121 x I.P. Basmati ** ** ** ** ** ** ** Pusa 1121 x Basmati ** ** ** ** ** 9.25 * ** ** ** ** RNR 2354 x Sumathi ** ** ** ** ** ** ** ** 1.44 RNR 2354 x I.P. Basmati ** ** ** ** ** * ** ** ** 8.77 ** RNR 2354 x Basmati ** ** ** * ** * ** ** ** ** Sumathi x I.P. Basmati ** 6.08 ** 4.53 * ** ** ** * ** ** ** Sumathi x Basmati ** 7.42 ** 5.84 ** ** ** ** ** * I.P. Basmati x Basmati ** ** ** ** ** ** ** ** ** ** 3.30 * * Significant at 5 % level, ** Significant at 1 % level MP: Heterosis over mid parent; BP: Heterosis over better parent; SH (Y): Standard heterosis for yield on MTU 1010; SH (Q): Standard heterosis for quality on Pusa 1121; ID: Inbreeding depression.

179 Table 4.6. Estimation of heterosis over mid parent, better parent, standard heterosis and inbreeding depression for kernel breadth, kernel L/B ratio and kernel length after cooking Crosses Kernel Breadth (mm) Kernel L/B ratio Kernel Length After Cooking (mm) Mean MP BP SH (Q) ID Mean MP BP SH (Q) ID Mean MP BP SH (Q) ID BPT 5204 x Akshyadhan ** ** * ** ** ** ** ** ** BPT 5204 x NLR * 4.55 * -6.40** ** ** ** 7.45 ** * BPT 5204 x Pusa ** ** 5.23** ** ** ** ** ** ** ** ** ** BPT 5204 x RNR ** ** ** ** ** ** ** BPT 5204 x Sumathi ** ** ** ** * * ** ** ** 4.50 BPT 5204 x I.P. Basmati ** 8.44 ** ** ** ** ** ** BPT 5204 x Basmati ** ** ** 9.35 ** ** ** ** ** 0.78 Akshyadhan x NLR * ** 9.99 ** ** * ** ** ** ** Akshyadhan x Pusa * 6.13 ** ** ** 3.92 * ** ** Akshyadhan x RNR ** ** 8.39 ** ** 11.93** ** 7.37 ** * Akshyadhan x Sumathi ** ** 4.07* 3.54 * ** ** ** ** Akshyadhan x I.P. Basmati ** ** ** ** ** ** ** ** Akshyadhan x Basmati ** ** ** 6.99 * ** ** ** * NLR 145 x Pusa * 3.30* * ** ** ** ** ** * NLR 145 x RNR ** ** ** ** ** ** ** ** * NLR 145 x Sumathi ** ** * ** ** ** * ** ** NLR 145 x I.P. Basmati * -4.07* ** ** ** ** ** ** NLR 145 x Basmati ** ** -6.40** ** ** ** 7.69 ** 9.80 ** * Pusa 1121 x RNR ** * -3.49* ** ** ** * Pusa 1121 x Sumathi * 6.83 ** * ** ** ** ** ** ** ** * Pusa 1121 x I.P. Basmati ** * * ** ** 5.88 ** Pusa 1121 x Basmati ** ** -4.84** * * 9.35 ** ** 4.81 * 6.86 ** * RNR 2354 x Sumathi * ** ** ** ** 4.72 * 8.82 ** ** RNR 2354 x I.P. Basmati ** ** ** ** * ** ** ** 9.80 ** ** RNR 2354 x Basmati ** ** -4.07* ** ** 6.73 ** 8.82 ** ** Sumathi x I.P. Basmati ** 7.34 ** ** ** ** ** * ** ** ** Sumathi x Basmati * 3.52 * ** ** ** ** ** ** ** ** I.P. Basmati x Basmati ** ** ** ** ** ** * Significant at 5 % level, ** Significant at 1 % level MP: Heterosis over mid parent; BP: Heterosis over better parent; SH (Q): Standard heterosis for quality on Pusa 1121; ID: Inbreeding depression.

180 Table 4.7. Estimation of heterosis over mid parent, better parent, standard heterosis and inbreeding depression for kernel elongation ratio and head rice recovery Crosses Kernel Elongation Ratio Head rice recovery (%) Mean MP BP SH (Q) ID Mean MP BP SH (Q) ID BPT 5204 x Akshyadhan ** ** ** ** ** ** ** BPT 5204 x NLR ** 9.91 ** * ** ** * BPT 5204 x Pusa ** ** ** ** ** 9.57 * BPT 5204 x RNR ** ** ** ** ** ** ** BPT 5204 x Sumathi ** ** ** ** ** 9.33 * ** BPT 5204 x I.P. Basmati ** ** ** ** * * BPT 5204 x Basmati ** ** ** ** ** ** 3.85 Akshyadhan x NLR ** ** ** ** ** ** Akshyadhan x Pusa ** ** ** ** Akshyadhan x RNR ** ** ** * Akshyadhan x Sumathi * ** ** 6.82 Akshyadhan x I.P. Basmati ** ** ** ** ** ** Akshyadhan x Basmati ** ** ** ** ** * NLR 145 x Pusa ** ** * ** ** NLR 145 x RNR ** ** * ** ** ** NLR 145 x Sumathi * ** * ** ** ** NLR 145 x I.P. Basmati ** ** ** ** ** 6.10 NLR 145 x Basmati ** ** ** * Pusa 1121 x RNR ** * ** ** Pusa 1121 x Sumathi * * ** ** Pusa 1121 x I.P. Basmati ** ** ** * ** Pusa 1121 x Basmati ** ** ** ** RNR 2354 x Sumathi ** * ** * RNR 2354 x I.P. Basmati ** * ** ** * RNR 2354 x Basmati ** ** ** ** ** Sumathi x I.P. Basmati ** * ** ** ** * 8.28 Sumathi x Basmati ** ** ** ** ** ** I.P. Basmati x Basmati ** ** ** ** 9.57 * 8.71 * Significant at 5 % level, ** Significant at 1 % level MP: Heterosis over mid parent; BP: Heterosis over better parent; SH (Q): Standard heterosis for quality on Pusa 1121; ID: Inbreeding depression.

181 Table 4.8: Analysis of variance (mean squares) for grain yield and grain characteristics Source of variation Replications Treatments Parents Hybrids Parents vs. Error Total Hybrids d.f Days to 50 % flowering ** ** ** ** ** Plant height (cm) ** ** ** ** Number of productive tillers/ plant ** ** 6.72 ** 8.22 ** Panicle length (cm) ** ** ** ** Panicle weight (g) ** ** ** ** Number of filled grains/ panicle ** ** ** ** grain weight (g) ** ** ** ** Grain yield/ plant (g) ** ** ** ** Kernel length (mm) ** 2.43 ** 1.36 ** 0.42 ** Kernel breadth (mm) ** ** ** * Kernel L/B ratio ** 0.87 ** 0.45 ** 0.29 ** Kernel length after cooking (mm) ** 8.44 ** 6.83 ** 6.76 ** Kernel elongation ratio ** ** ** ** Head rice recovery (%) ** ** ** ** *Significant at 5 % level, ** Significant at 1 % level

182 Table 4.9. Analysis of variance for combining ability for grain yield, yield contributing characters and grain characteristics Source of variation d.f. Days to 50 % flowering Plant height (cm) Number of productive tillers/ plant Panicle length (cm) Panicle weight (g) Number of filled grains/ panicle 1000 grain weight (g) Grain yield/ plant (g) Kernel length (mm) Kernel breadth (mm) Kernel l/b ratio Kernel length after cooking (mm) Kernel elongation ratio Head rice recovery (%) GCA ** ** 4.09 ** 33.1 ** ** ** 53.29** ** 1.63** 72.97** 0.50** 4.03** ** ** SCA ** 59.40** 2.18 ** 3.18** 38.09** ** 4.75** 37.54** 0.24** 60.95** 0.10** 1.97** ** ** Error σ 2 gca σ 2 sca σ 2 gca / σ 2 sca ** Significant at 1 % level

183 Table General combining ability (gca) effects of parents for yield and grain characteristics Parents Days to 50 % flowering Plant height (cm) Number of productive tillers/ plant Panicle length (cm) Panicle weight (g) Number of filled grains/ panicle 1000 grain weight (g) Grain yield/ plant (g) Kernel length (mm) Kernel breadth (mm) Kernel l/b ratio Kernel length after cooking (mm) Kernel elongation ratio Head rice recovery (%) BPT ** ** 0.74 ** ** 2.22** ** 1.75 ** ** ** ** ** Akshyadhan * ** ** 6.58** ** 3.27 ** 5.85 ** ** 2.21 ** ** ** NLR ** ** ** ** 0.43 ** ** ** 1.58 ** ** ** ** PUSA ** ** ** ** 1.81 ** ** 0.56 ** 3.54 ** 0.25 ** ** ** ** RNR ** ** ** ** ** * ** ** ** ** Sumathi ** 7.59 ** * 1.55 ** -4.17** ** 1.57 ** 1.28 ** 0.41 ** ** 0.35 ** ** Improved Pusa Basmati 0.66 ** ** ** 1.31 ** -1.22** ** ** ** 0.20 ** ** 0.22 ** 0.96 ** 8.13 ** ** Basmati ** ** * 0.89 ** -2.06** ** 2.21 ** 0.13 ** ** 0.43 ** 2.69 * 0.69 SE (gi) ± SE (gi-gj) ± *Significant at 5 % level, ** Significant at 1 % level

184 Table Specific combining ability (sca) effects of crosses for yield and grain characteristics Genotype Days to 50 % flowering Plant height (cm) Number of productive tillers/ plant Panicle length (cm) Panicle weight (g) Number of filled grains/ panicle 1000 grain weight (g) Grain yield/ plant (g) Kernel length (mm) Kernel breadth (mm) Kernel l/b ratio Kernel length after cooking (mm) Kernel elongation ratio BPT 5204 x Akshyadhan ** ** 30.09** ** -0.23** 7.19** -0.26** -1.91** ** 1.37 BPT 5204 x NLR ** ** ** -2.98** -0.46** -4.17* -0.20** 0.92** 30.47** 9.82** BPT 5204 x Pusa ** -1.02** 2.51** ** 22.18* 1.78** 13.24** -0.19** 13.86** -0.38** -0.81** ** BPT 5204 x RNR ** * ** -0.39** ** ** 60.90** ** BPT 5204 x Sumathi -4.91** * * ** 1.06** 8.86** 0.43** -0.44** ** -5.03** BPT 5204 x I.P. Basmati 3.26** ** ** ** -2.26* ** -0.22** -0.65** -8.93* ** BPT 5204 x Basmati ** -2.51** -1.74** -6.10** 24.00* -1.57** ** -8.34** 0.56** -0.52** ** Akshyadhan x NLR ** -3.15* -2.37** ** -0.68* 2.19* * 0.15** 2.71** 41.17** 1.37 Akshyadhan x Pusa ** -4.59** * 7.68** ** 2.76** 4.07** ** Akshyadhan x RNR ** 8.13** ** ** 5.79** 0.14** -0.54** ** -5.02** Akshyadhan x Sumathi -1.44* 7.82** ** ** * 9.26** -0.11* -0.65** ** 0.46 Akshyadhan x I.P. Basmati -2.94** 6.67** 1.42** 1.58* * -2.73** 0.70** ** 1.34** Akshyadhan x Basmati ** ** ** -5.00** 0.21** ** 36.20** -6.48** Head rice recovery (%) Cont.

185 Table 4.11 (Cont.) Genotype Days to 50 % flowering Plant height (cm) Number of productive tillers/ plant Panicle length (cm) Panicle weight (g) Number of filled grains/ panicle NLR 145 x Pusa ** ** ** 3.83** -5.25** 0.19** 5.56** ** ** -5.23** NLR 145 x RNR * * ** * 0.99** 9.23* NLR 145 x Sumathi -3.57** 3.54* 0.86* ** 6.91** ** 0.12* -1.12** ** 4.97** NLR 145 x I.P. Basmati -8.07** ** * 24.80** 2.07** * ** ** -3.77** NLR 145 x Basmati ** ** ** ** -8.31** 0.47** 0.40** -7.17* -6.13** Pusa 1121 x RNR ** 5.00** -1.63** 2.30** ** ** ** -3.54* ** Pusa 1121 x Sumathi ** ** -1.48** ** 0.82** -6.26** 1.08** ** 2.45** 11.17** 2.08 Pusa 1121 x I.P. Basmati -6.31** ** -2.38** 2.52* ** -2.89** -0.40** -5.31** -0.12* -0.56** Pusa 1121 x Basmati ** -7.94** 1.60** ** -2.94** -0.27** -7.61** * 1.00 RNR 2354 x Sumathi -4.41** ** ** ** 20.14* -1.47** -7.68** * ** RNR 2354 x I.P. Basmati -5.24** * 1.79** -7.65** 56.38** 2.51** 7.92** 0.20** -5.77** 0.26** -0.48** ** 0.12 RNR 2354 x Basmati ** -0.64* 4.46** -0.21** ** Sumathi x I.P. Basmati -4.64** 8.82** ** -2.76* ** 8.21** -0.68** 7.36** -0.58** ** ** Sumathi x Basmati ** * 22.96* 1.64** ** ** 1.24** 48.17** -3.00** I.P. Basmati x Basmati ** ** ** ** 7.32** -0.24** * -1.57** ** -3.64** SE (Sij) ± SE (Sij-Sik) ± SE (Sij-Skl) ± *Significant at 5 % level, ** Significant at 1 % level 1000 grain weight (g) Grain yield/ plant (g) Kernel length (mm) Kernel breadth (mm) Kernel l/b ratio Kernel length after cooking (mm) Kernel elongati on ratio Head rice recovery (%)

186 Table Genetic parameters for yield and quality characters in F 2 progenies Parameter Days to 50 % flowering Plant height (cm) Number of productive tillers/ plant Panicle length (cm) Panicle weight (g) Number of filled grains/ panicle 1000 grain weight (g) Grain yield/ plant (g) Kernel length (mm) Kernel breadth (mm) Kernel l/b ratio Kernel length after cooking (mm) Kernel elongation ratio PCV (%) GCV (%) Head rice recovery (%) h 2 (narrow sense) (%) GA (%) GAM (%) h 2 = heritability, GA = Genetic advance, GAM = Genetic advance as per cent of mean.

187 Table Mean performance of F 3 progenies for yield and grain quality characteristics Genotype Days to 50 % flowering Plant height (cm) Number of productive tillers/ plant Panicle length (cm) Panicle weight (g) Number of filled grains/ panicle 1000 grain weight (g) Grain yield/ plant (g) Kernel length (mm) Kernel breadth (mm) Kernel l/b ratio Kernel length after cooking (mm) Kernel elongation ratio F 3 Crosses BPT 5204 x Akshyadhan BPT 5204 x NLR BPT 5204 x Pusa BPT 5204 x RNR BPT 5204 x Sumathi BPT 5204 x I.P. Basmati BPT 5204 x Basmati Akshyadhan x NLR Akshyadhan x Pusa Akshyadhan x RNR Akshyadhan x Sumathi Akshyadhan x I.P. Basmati Akshyadhan x Basmati NLR 145 x Pusa NLR 145 x RNR NLR 145 x Sumathi NLR 145 x I.P. Basmati NLR 145 x Basmati Cont. Head rice recovery (%)

188 Table 4.60 (Cont.). Genotype Days to 50 % flowering Plant height (cm) Number of productive tillers/ plant Panicle length (cm) Panicle weight (g) Number of filled grains/ panicle 1000 grain weight (g) Grain yield/ plant (g) Kernel length (mm) Kernel breadth (mm) Kernel l/b ratio Kernel length after cooking (mm) Pusa 1121 x RNR Pusa 1121 x Sumathi Pusa 1121 x I.P. Basmati Pusa 1121 x Basmati RNR 2354 x Sumathi RNR 2354 x I.P. Basmati RNR 2354 x Basmati Sumathi x I.P. Basmati Sumathi x Basmati I.P. Basmati x Basmati F 3 Mean C.V (%) SE (d) C.D (5%) Kernel elongati on ratio Head rice recovery (%)

189 Table Genetic parameters for yield and quality characters in F 3 progenies Parameter Days to 50 % flowering Plant height (cm) Number of productive tillers/ plant Panicle length (cm) Panicle weight (g) Number of filled grains/ panicle 1000 grain weight (g) Grain yield/ plant (g) Kernel length (mm) Kernel breadth (mm) Kernel l/b ratio Kernel length after cooking (mm) Kernel elongati on ratio PCV (%) GCV (%) Head rice recovery (%) h 2 (broad sense) (%) GA (%) GAM (%) h 2 = heritability, GA = Genetic advance, GAM = Genetic advance as per cent of mean.

190 Table Simple correlations coefficients among grain yield per plant and its component characters in F 1, F 2 and F 3 generations Character Generation Days to 50 % flowering Days to 50 % flowering Plant height (cm) Panicle length (cm) Number of productive tillers/ plant Panicle weight (g) Number of filled grains/ panicle 1000 grain weight (g) Kernel length (mm) Kernel breadth (mm) kernel L/B ratio Grain yield/ plant (g) F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F Plant height (cm) ** * Panicle length (cm) ** ** * ** * ** Number of productive tillers/ plant * ** ** ** ** ** Panicle weight (g) ** * ** * * ** ** ** Number of filled grains/ panicle ** ** ** ** * ** ** ** ** ** ** grain weight (g) ** ** ** ** ** ** ** ** ** * ** ** Kernel length (mm) ** ** ** ** ** ** ** ** * ** * ** ** ** ** ** Kernel breadth (mm) * ** ** ** ** * * ** * ** ** ** ** * Significant at 5 per cent level; ** Significant at 1 per cent level; the values in the parenthesis are genotypic correlations Kernel L/B ratio ** ** ** * * ** * * * ** * ** ** * ** ** ** ** ** Grain yield/ plant (g) ** ** ** * ** ** ** ** ** * ** ** ** ** **

191 Table Path coefficients for yield and yield components in F 1, F 2 and F 3 generations Character Generation Days to 50 % flowering Days to 50 % flowering Plant height (cm) Panicle length (cm) Number of productive tillers/ plant Panicle weight (g) Number of filled grains/ panicle 1000 grain weight (g) Kernel length (mm) Kernel breadth (mm) kernel L/B ratio F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F 3 F 1 F 2 F Plant height (cm) Panicle length (cm) Number of productive tillers/ plant Panicle weight (g) Number of filled grains/ panicle grain weight (g) Kernel length (mm) Bold values are direct effects; residual effect F 1 = ; F 2 = ; F 3 = Kernel breadth (mm) Kernel L/B ratio Grain yield/ plant (g) ** ** ** * ** ** ** ** ** * ** ** ** ** **

192 Sl. No. Table Generation means for days to 50% flowering Cross P 1 P 2 F 1 F 2 F 3 SE± 1 BPT 5204 x Akshyadhan BPT 5204 x Pusa BPT 5204 x Sumathi Akshyadhan x NLR Akshyadhan x Pusa NLR 145 x Sumathi RNR 2354 x I.P Basmati RNR 2354 x Basmati Sumathi x I.P Basmati I.P Basmati x Basmati CD (5%) S. NO Table Scaling test values for days to 50 % flowering Cross C Scaling tests D χ 2 value of JST (3 parameter) at 2 d.f 1 BPT 5204 x Akshyadhan 26.33**± **± ** 2 BPT 5204 x Pusa **± **± ** 3 BPT 5204 x Sumathi 34.33**± **± ** 4 Akshyadhan x NLR **± **± ** 5 Akshyadhan x Pusa **± **± ** 6 NLR 145 x Sumathi 22.33**± **± ** 7 RNR 2354 x I.P Basmati 39.33**± **± ** 8 RNR 2354 x Basmati **± **± ** 9 Sumathi x I.P Basmati 8.00**± **± ** 10 I.P Basmati x Basmati **± **± ** S. NO Table Gene effects for days to 50 % flowering Cross Components m d h i l 1 BPT 5204 x Akshyadhan **± ** =± **± ± 0.61NS 19.56**± BPT 5204 x Pusa **± **± **± **± **± BPT 5204 x Sumathi **± **± **± **± **± Akshyadhan x NLR **± **± **± **± **± Akshyadhan x Pusa **± **± **± **± **± NLR 145 x Sumathi **± **± **± **± **± RNR 2354 x I.P Basmati **± **± **± **± **± RNR 2354 x Basmati **± **± **± **± **± Sumathi x I.P Basmati **± **± **± **± **± I.P Basmati x Basmati **± **± **± **± **± 1.77 *Significant at 5 % level, ** Significant at 1 % level

193 Sl. No. Table Generation means for plant height (cm) Cross P 1 P 2 F 1 F 2 F 3 SE± CD (5%) 1 BPT 5204 x Akshyadhan BPT 5204 x Pusa BPT 5204 x Sumathi Akshyadhan x NLR Akshyadhan x Pusa NLR 145 x Sumathi RNR 2354 x I.P Basmati RNR 2354 x Basmati Sumathi x I.P Basmati I.P Basmati x Basmati S. NO Table Scaling test values for plant height Cross C Scaling tests D χ 2 value of JST (3 parameter) at 2 d.f 1 BPT 5204 x Akshyadhan -9.84**± **± ** 2 BPT 5204 x Pusa **± **± ** 3 BPT 5204 x Sumathi 6.03**± **± ** 4 Akshyadhan x NLR **± **± ** 5 Akshyadhan x Pusa **± **± ** 6 NLR 145 x Sumathi **± **± ** 7 RNR 2354 x I.P Basmati **± **± ** 8 RNR 2354 x Basmati **± **± ** 9 Sumathi x I.P Basmati 29.05**± **± ** 10 I.P Basmati x Basmati **± **± ** S. NO Table Gene effects for plant height Cross Components m d h i l 1 BPT 5204 x Akshyadhan 90.94**± **± **± **± ** ± BPT 5204 x Pusa **± **± **± **± **± BPT 5204 x Sumathi **± **± **± **± **± Akshyadhan x NLR **± **± **± **± **± Akshyadhan x Pusa **± **± **± **± **± NLR 145 x Sumathi **± **± **± **± **± RNR 2354 x I.P Basmati **± **± **± **± **± RNR 2354 x Basmati **± **± **± **± **± Sumathi x I.P Basmati **± **± **± **± **± I.P Basmati x Basmati **± **± **± **± **± 0.92 *Significant at 5 % level, ** Significant at 1 % level

194 Sl. No. Table Generation means for number of productive tillers/plant Cross P 1 P 2 F 1 F 2 F 3 SE± 1 BPT 5204 x Akshyadhan BPT 5204 x Pusa BPT 5204 x Sumathi Akshyadhan x NLR Akshyadhan x Pusa NLR 145 x Sumathi RNR 2354 x I.P Basmati RNR 2354 x Basmati Sumathi x I.P Basmati I.P Basmati x Basmati CD (5%) S. NO Table Scaling test values for number of productive tillers/plant Cross C Scaling tests D χ 2 value of JST (3 parameter) at 2 d.f 1 BPT 5204 x Akshyadhan 11.06**± ± 0.36 NS ** 2 BPT 5204 x Pusa **± **± ** 3 BPT 5204 x Sumathi 9.83**± **± ** 4 Akshyadhan x NLR **± **± ** 5 Akshyadhan x Pusa **± **± ** 6 NLR 145 x Sumathi 6.65**± **± ** 7 RNR 2354 x I.P Basmati 10.93**± **± ** 8 RNR 2354 x Basmati **± **± ** 9 Sumathi x I.P Basmati 14.69**± **± ** 10 I.P Basmati x Basmati **± **± ** S. NO Table Gene effects for number of productive tillers/plant Cross Components m d h i l 1 BPT 5204 x Akshyadhan 14.27**± **± **± **± **± BPT 5204 x Pusa **± **± **± **± **± BPT 5204 x Sumathi 12.60**± **± **± **± **± Akshyadhan x NLR **± **± **± **± **± Akshyadhan x Pusa **± **± **± **± ± 0.99 NS 6 NLR 145 x Sumathi 11.78**± ± 0.09NS -3.11**± **± *± RNR 2354 x I.P Basmati 11.20**± **± **± **± **± RNR 2354 x Basmati **± **± **± **± **± Sumathi x I.P Basmati 13.24**± **± **± **± **± I.P Basmati x Basmati **± **± **± **± ± 2.00 NS *Significant at 5 % level, ** Significant at 1 % level

195 Sl. No. Table Generation means for panicle length (cm) Cross P 1 P 2 F 1 F 2 F 3 SE± CD (5%) 1 BPT 5204 x Akshyadhan BPT 5204 x Pusa BPT 5204 x Sumathi Akshyadhan x NLR Akshyadhan x Pusa NLR 145 x Sumathi RNR 2354 x I.P Basmati RNR 2354 x Basmati Sumathi x I.P Basmati I.P Basmati x Basmati S. NO Table Scaling test values for panicle length Cross C Scaling tests D χ 2 value of JST (3 parameter) at 2 d.f 1 BPT 5204 x Akshyadhan -5.02**± ± 0.46 NS ** 2 BPT 5204 x Pusa **± **± ** 3 BPT 5204 x Sumathi 0.83**± **± ** 4 Akshyadhan x NLR **± **± ** 5 Akshyadhan x Pusa **± **± ** 6 NLR 145 x Sumathi 13.09**± **± ** 7 RNR 2354 x I.P Basmati -0.62**± **± ** 8 RNR 2354 x Basmati **± **± ** 9 Sumathi x I.P Basmati **± **± ** 10 I.P Basmati x Basmati **± **± ** S. NO Table Gene effects for panicle length Cross Components m d h i l 1 BPT 5204 x Akshyadhan 24.54**± **± **± **± **± BPT 5204 x Pusa **± **± **± **± **± BPT 5204 x Sumathi 24.52**± **± **± **± **± Akshyadhan x NLR **± **± **± **± **± Akshyadhan x Pusa **± **± **± **± **± NLR 145 x Sumathi 28.95**± **± **± **± **± RNR 2354 x I.P Basmati 27.02**± **± **± **± **± RNR 2354 x Basmati **± **± **± **± **± Sumathi x I.P Basmati 27.23**± **± **± **± **± I.P Basmati x Basmati **± **± **± **± **± 0.38 *Significant at 5 % level, ** Significant at 1 % level

196 Sl. No. Table Generation means for panicle weight (g) Cross P 1 P 2 F 1 F 2 F 3 SE± 1 BPT 5204 x Akshyadhan BPT 5204 x Pusa BPT 5204 x Sumathi Akshyadhan x NLR Akshyadhan x Pusa NLR 145 x Sumathi RNR 2354 x I.P Basmati RNR 2354 x Basmati Sumathi x I.P Basmati I.P Basmati x Basmati CD (5%) S. NO Table Scaling test values for panicle weight Cross C Scaling tests D χ 2 value of JST (3 parameter) at 2 d.f 1 BPT 5204 x Akshyadhan -5.70**± **± ** 2 BPT 5204 x Pusa **± **± ** 3 BPT 5204 x Sumathi -3.50**± **± ** 4 Akshyadhan x NLR **± **± ** 5 Akshyadhan x Pusa **± **± ** 6 NLR 145 x Sumathi -0.13NS± **± ** 7 RNR 2354 x I.P Basmati -5.16**± **± ** 8 RNR 2354 x Basmati **± **± ** 9 Sumathi x I.P Basmati 1.79**± **± ** 10 I.P Basmati x Basmati **± **± ** S. NO Table Gene effects for panicle weight Cross Components m d h i l 1 BPT 5204 x Akshyadhan 2.07**± **± **± **± **± BPT 5204 x Pusa **± **± **± **± **± BPT 5204 x Sumathi 2.29**± **± **± **± **± Akshyadhan x NLR **± **± **± **± **± Akshyadhan x Pusa **± **± **± **± **± NLR 145 x Sumathi 2.94**± **± **± **± **± RNR 2354 x I.P Basmati 2.16**± **± **± **± **± RNR 2354 x Basmati **± **± **± **± **± Sumathi x I.P Basmati 2.59**± **± **± **± **± I.P Basmati x Basmati **± **± **± NS± **± 0.15 *Significant at 5 % level, ** Significant at 1 % level

197 Sl. No. Table Generation means for number of filled grains/panicle Cross P 1 P 2 F 1 F 2 F 3 SE± CD (5%) 1 BPT 5204 x Akshyadhan BPT 5204 x Pusa BPT 5204 x Sumathi Akshyadhan x NLR Akshyadhan x Pusa NLR 145 x Sumathi RNR 2354 x I.P Basmati RNR 2354 x Basmati Sumathi x I.P Basmati I.P Basmati x Basmati S. NO Table Scaling test values for number of filled grains/panicle Cross C Scaling tests D χ 2 value of JST (3 parameter) at 2 d.f 1 BPT 5204 x Akshyadhan **± **± ** 2 BPT 5204 x Pusa **± **± ** 3 BPT 5204 x Sumathi **± **± ** 4 Akshyadhan x NLR **± **± ** 5 Akshyadhan x Pusa **± **± ** 6 NLR 145 x Sumathi **± **± ** 7 RNR 2354 x I.P Basmati **± **± ** 8 RNR 2354 x Basmati **± **± ** 9 Sumathi x I.P Basmati **± **± ** 10 I.P Basmati x Basmati **± **± ** S. NO Table Gene effects for number of filled grains/panicle Cross Components m d h i l 1 BPT 5204 x Akshyadhan 92.57**± **± **± **± **± BPT 5204 x Pusa **± **± **± **± **± BPT 5204 x Sumathi **± **± **± **± **± Akshyadhan x NLR **± **± **± **± **± Akshyadhan x Pusa **± **± **± **± **± NLR 145 x Sumathi **± **± **± **± **± RNR 2354 x I.P Basmati 91.39**± **± **± **± **± RNR 2354 x Basmati **± **± **± **± **± Sumathi x I.P Basmati 77.91**± **± **± **± **± I.P Basmati x Basmati **± **± **± **± **± *Significant at 5 % level, ** Significant at 1 % level

198 Sl. No. Table Generation means for 1000 grain weight (g) Cross P 1 P 2 F 1 F 2 F 3 SE± 1 BPT 5204 x Akshyadhan BPT 5204 x Pusa BPT 5204 x Sumathi Akshyadhan x NLR Akshyadhan x Pusa NLR 145 x Sumathi RNR 2354 x I.P Basmati RNR 2354 x Basmati Sumathi x I.P Basmati I.P Basmati x Basmati CD (5%) S. NO Table Scaling test values for 1000 grain weight (g) Cross C Scaling tests D χ 2 value of JST (3 parameter) at 2 d.f 1 BPT 5204 x Akshyadhan 2.66**± **± ** 2 BPT 5204 x Pusa **± **± ** 3 BPT 5204 x Sumathi 2.53**± **± ** 4 Akshyadhan x NLR ± 0.58NS -5.47**± ** 5 Akshyadhan x Pusa **± **± ** 6 NLR 145 x Sumathi 6.50**± **± ** 7 RNR 2354 x I.P Basmati 8.31**± **± ** 8 RNR 2354 x Basmati **± **± ** 9 Sumathi x I.P Basmati -1.88**± **± ** 10 I.P Basmati x Basmati **± **± ** S. NO Table Gene effects for 1000 grain weight (g) Cross Components m d h i l 1 BPT 5204 x Akshyadhan 20.51**± **± **± **± **± BPT 5204 x Pusa **± **± **± **± **± BPT 5204 x Sumathi 18.60**± **± **± **± **± Akshyadhan x NLR **± **± **± **± **± Akshyadhan x Pusa **± **± **± **± **± NLR 145 x Sumathi 23.67**± **± **± **± **± RNR 2354 x I.P Basmati 20.78**± **± **± **± **± RNR 2354 x Basmati **± **± **± **± **± Sumathi x I.P Basmati 23.67**± **± **± **± **± I.P Basmati x Basmati **± **± **± **± **±0.15 *Significant at 5 % level, ** Significant at 1 % level

199 Sl. No. Table Generation means for grain yield/plant (g) Cross P 1 P 2 F 1 F 2 F 3 SE± 1 BPT 5204 x Akshyadhan BPT 5204 x Pusa BPT 5204 x Sumathi Akshyadhan x NLR Akshyadhan x Pusa NLR 145 x Sumathi RNR 2354 x I.P Basmati RNR 2354 x Basmati Sumathi x I.P Basmati I.P Basmati x Basmati CD (5%) S. NO Table Scaling test values for grain yield/plant (g) Cross C Scaling tests D χ 2 value of JST (3 parameter) at 2 d.f 1 BPT 5204 x Akshyadhan **± **± ** 2 BPT 5204 x Pusa **± **± ** 3 BPT 5204 x Sumathi **± **± ** 4 Akshyadhan x NLR ± 0.07NS -0.10**± ** 5 Akshyadhan x Pusa **± **± ** 6 NLR 145 x Sumathi 1.35**± **± ** 7 RNR 2354 x I.P Basmati **± **± ** 8 RNR 2354 x Basmati **± **± ** 9 Sumathi x I.P Basmati 6.92**± **± ** 10 I.P Basmati x Basmati **± **± ** S. NO Table Gene effects for grain yield/plant (g) Cross Components m d h i l 1 BPT 5204 x Akshyadhan 22.11**± **± **± **± **± BPT 5204 x Pusa **± **± **± **± **± BPT 5204 x Sumathi 20.97**± **± **± **± **± Akshyadhan x NLR **± **± **± **± ± 0.21NS 5 Akshyadhan x Pusa **± **± **± **± **± NLR 145 x Sumathi 24.30**± **± **± **± **± RNR 2354 x I.P Basmati 17.48**± **± **± **± **± RNR 2354 x Basmati **± **± **± **± **± Sumathi x I.P Basmati 18.10**± **± **± **± **± I.P Basmati x Basmati **± **± **± **± **± 1.97 *Significant at 5 % level, ** Significant at 1 % level

200 Sl. No. Table Generation means for kernel length (mm) Cross P 1 P 2 F 1 F 2 F 3 SE± 1 BPT 5204 x Akshyadhan BPT 5204 x Pusa BPT 5204 x Sumathi Akshyadhan x NLR Akshyadhan x Pusa NLR 145 x Sumathi RNR 2354 x I.P Basmati RNR 2354 x Basmati Sumathi x I.P Basmati I.P Basmati x Basmati CD (5%) S. NO Table Scaling test values for kernel length (mm) Cross C Scaling tests D χ 2 value of JST (3 parameter) at 2 d.f 1 BPT 5204 x Akshyadhan 0.12*± **± ** 2 BPT 5204 x Pusa **± **± ** 3 BPT 5204 x Sumathi -3.38**± **± ** 4 Akshyadhan x NLR ± 0.10NS 0.82**± ** 5 Akshyadhan x Pusa **± ± 0.17NS ** 6 NLR 145 x Sumathi -0.56**± **± ** 7 RNR 2354 x I.P Basmati -2.04**± **± ** 8 RNR 2354 x Basmati **± ± 0.13NS ** 9 Sumathi x I.P Basmati -0.94**± **± ** 10 I.P Basmati x Basmati **± **± ** S. NO Table Gene effects for kernel length (mm) Cross Components m d h i l 1 BPT 5204 x Akshyadhan 5.23**± **± **± **± **± BPT 5204 x Pusa **± **± **± **± **± BPT 5204 x Sumathi 5.60**± **± **± **± **± Akshyadhan x NLR **± **± **± **± **± Akshyadhan x Pusa **± **± ± 0.11NS -2.02**± **± NLR 145 x Sumathi 6.20**± **± **± **± **± RNR 2354 x I.P Basmati 5.79**± **± **± **± **± RNR 2354 x Basmati **± **± **± **± **± Sumathi x I.P Basmati 6.49**± **± **± **± **± I.P Basmati x Basmati **± **± **± **± ± 0.20NS *Significant at 5 % level, ** Significant at 1 % level

201 Sl. No. Table Generation means for kernel breadth (mm) Cross P 1 P 2 F 1 F 2 F 3 SE± 1 BPT 5204 x Akshyadhan BPT 5204 x Pusa BPT 5204 x Sumathi Akshyadhan x NLR Akshyadhan x Pusa NLR 145 x Sumathi RNR 2354 x I.P Basmati RNR 2354 x Basmati Sumathi x I.P Basmati I.P Basmati x Basmati CD (5%) S. NO Table Scaling test values for kernel breadth (mm) Cross C Scaling tests D χ 2 value of JST (3 parameter) at 2 d.f 1 BPT 5204 x Akshyadhan 0.04*± **± ** 2 BPT 5204 x Pusa **± **± ** 3 BPT 5204 x Sumathi -0.21**± ± 0.01NS ** 4 Akshyadhan x NLR **± **± ** 5 Akshyadhan x Pusa ± 0.01NS 0.27**± ** 6 NLR 145 x Sumathi 0.16**± **± ** 7 RNR 2354 x I.P Basmati 0.33**± **± ** 8 RNR 2354 x Basmati **± **± ** 9 Sumathi x I.P Basmati 0.53**± **± ** 10 I.P Basmati x Basmati **± **± ** S. NO Table Gene effects for kernel breadth (mm) Cross Components m d h i l 1 BPT 5204 x Akshyadhan 1.67**± **± **± **± **± BPT 5204 x Pusa **± **± **± **± **± BPT 5204 x Sumathi 1.60**± **± **± **± **± Akshyadhan x NLR **± **± **± **± **± Akshyadhan x Pusa **± **± **± **± **± NLR 145 x Sumathi 1.70**± **± **± **± **± RNR 2354 x I.P Basmati 1.70**± **± **± **± **± RNR 2354 x Basmati **± **± **± **± **± Sumathi x I.P Basmati 1.63**± **± **± **± **± I.P Basmati x Basmati **± **± ± 0.01NS -0.15**± **± 0.03 *Significant at 5 % level, ** Significant at 1 % level

202 Sl. No. Table Generation means for kernel L/B ratio Cross P 1 P 2 F 1 F 2 F 3 SE± 1 BPT 5204 x Akshyadhan BPT 5204 x Pusa BPT 5204 x Sumathi Akshyadhan x NLR Akshyadhan x Pusa NLR 145 x Sumathi RNR 2354 x I.P Basmati RNR 2354 x Basmati Sumathi x I.P Basmati I.P Basmati x Basmati CD (5%) S. NO Table Scaling test values and gene effects for kernel L/B ratio Cross C Scaling tests D χ 2 value of JST (3 parameter) at 2 d.f 1 BPT 5204 x Akshyadhan 0.01± 0.04NS 0.48**± ** 2 BPT 5204 x Pusa **± **± ** 3 BPT 5204 x Sumathi -1.34**± **± ** 4 Akshyadhan x NLR **± **± ** 5 Akshyadhan x Pusa **± **± ** 6 NLR 145 x Sumathi -0.49**± **± ** 7 RNR 2354 x I.P Basmati -1.88**± **± ** 8 RNR 2354 x Basmati **± **± ** 9 Sumathi x I.P Basmati -1.69**± **± ** 10 I.P Basmati x Basmati ± 0.09NS -0.51**± ** S. NO Table Scaling test values and gene effects for kernel L/B ratio Cross Components m d h i l 1 BPT 5204 x Akshyadhan 3.14**± **± **± **± **± BPT 5204 x Pusa **± **± **± **± **± BPT 5204 x Sumathi 3.22**± **± **± **± **± Akshyadhan x NLR **± **± **± **± **± Akshyadhan x Pusa **± **± **± **± ± 0.15NS 6 NLR 145 x Sumathi 3.73**± **± **± **± **± RNR 2354 x I.P Basmati 3.46**± **± **± **± **± RNR 2354 x Basmati **± **± **± **± **± Sumathi x I.P Basmati 3.99**± ± 0.02NS 0.23**± **± **± I.P Basmati x Basmati **± **± **± **± **± 0.16 *Significant at 5 % level, ** Significant at 1 % level

203 Sl. No. Table Generation means for kernel length after cooking (mm) Cross P 1 P 2 F 1 F 2 F 3 SE± 1 BPT 5204 x Akshyadhan BPT 5204 x Pusa BPT 5204 x Sumathi Akshyadhan x NLR Akshyadhan x Pusa NLR 145 x Sumathi RNR 2354 x I.P Basmati RNR 2354 x Basmati Sumathi x I.P Basmati I.P Basmati x Basmati CD (5%) S. NO Table Scaling test values and gene effects for kernel length after cooking (mm) Cross C Scaling tests D χ 2 value of JST (3 parameter) at 2 d.f 1 BPT 5204 x Akshyadhan 2.60**± **± ** 2 BPT 5204 x Pusa **± **± ** 3 BPT 5204 x Sumathi -2.29**± **± ** 4 Akshyadhan x NLR **± **± ** 5 Akshyadhan x Pusa **± **± ** 6 NLR 145 x Sumathi -4.69**± **± ** 7 RNR 2354 x I.P Basmati -8.50**± **± ** 8 RNR 2354 x Basmati **± *± ** 9 Sumathi x I.P Basmati **± **± ** 10 I.P Basmati x Basmati **± **± ** S. NO Table Scaling test values and gene effects for kernel length after cooking (mm) Cross Components m d h i l 1 BPT 5204 x Akshyadhan 8.85**± **± **± **± BPT 5204 x Pusa **± **± **± **± **± BPT 5204 x Sumathi 8.98**± **± **± ± 0.08NS -1.41**± Akshyadhan x NLR **± **± **± **± **± Akshyadhan x Pusa **± **± ± 0.36NS -3.15**± **± NLR 145 x Sumathi 8.63**± **± **± **± **± RNR 2354 x I.P Basmati 9.35**± **± **± **± **± RNR 2354 x Basmati **± **± **± **± **± Sumathi x I.P Basmati 9.58**± **± **± **± **± I.P Basmati x Basmati **± **± **± **± **± 0.49 *Significant at 5 % level, ** Significant at 1 % level

204 Sl. No. Table Generation means for kernel elongation ratio Cross P 1 P 2 F 1 F 2 F 3 SE± 1 BPT 5204 x Akshyadhan BPT 5204 x Pusa BPT 5204 x Sumathi Akshyadhan x NLR Akshyadhan x Pusa NLR 145 x Sumathi RNR 2354 x I.P Basmati RNR 2354 x Basmati Sumathi x I.P Basmati I.P Basmati x Basmati CD (5%) S. NO Table Scaling test values for kernel elongation ratio Cross C Scaling tests D χ 2 value of JST (3 parameter) at 2 d.f 1 BPT 5204 x Akshyadhan 0.42**± **± ** 2 BPT 5204 x Pusa **± **± ** 3 BPT 5204 x Sumathi 0.35**± **± ** 4 Akshyadhan x NLR **± **± ** 5 Akshyadhan x Pusa **± **± ** 6 NLR 145 x Sumathi -0.65**± ± 0.01NS ** 7 RNR 2354 x I.P Basmati -0.79**± **± ** 8 RNR 2354 x Basmati **± **± ** 9 Sumathi x I.P Basmati -2.05**± **± ** 10 I.P Basmati x Basmati **± **± ** S. NO Table Gene effects for kernel elongation ratio Cross Components m d h i l 1 BPT 5204 x Akshyadhan 1.69**± **± **± **± **± BPT 5204 x Pusa **± **± **± **± **± BPT 5204 x Sumathi 1.60**± **± ± 0.02NS 0.68**± **± Akshyadhan x NLR **± **± **± **± **± Akshyadhan x Pusa **± **± **± ± 0.03NS 0.39**± NLR 145 x Sumathi 1.39**± **± **± **± **± RNR 2354 x I.P Basmati 1.62**± **± ± 0.03NS -0.31**± **± RNR 2354 x Basmati **± **± **± **± **± Sumathi x I.P Basmati 1.47**± **± **± **± **± I.P Basmati x Basmati **± **± **± **± **± 0.04 *Significant at 5 % level, ** Significant at 1 % level

205 Sl. No. Table Generation means for head rice recovery Cross P 1 P 2 F 1 F 2 F 3 SE± CD (5%) 1 BPT 5204 x Akshyadhan BPT 5204 x Pusa BPT 5204 x Sumathi Akshyadhan x NLR Akshyadhan x Pusa NLR 145 x Sumathi RNR 2354 x I.P Basmati RNR 2354 x Basmati Sumathi x I.P Basmati I.P Basmati x Basmati S. NO Table Scaling test values for head rice recovery Cross C Scaling tests D χ 2 value of JST (3 parameter) at 2 d.f 1 BPT 5204 x Akshyadhan **± **± ** 2 BPT 5204 x Pusa **± **± ** 3 BPT 5204 x Sumathi 4.20**± **± ** 4 Akshyadhan x NLR **± **± ** 5 Akshyadhan x Pusa **± **± ** 6 NLR 145 x Sumathi **± **± ** 7 RNR 2354 x I.P Basmati **± **± ** 8 RNR 2354 x Basmati **± **± ** 9 Sumathi x I.P Basmati 18.80**± **± ** 10 I.P Basmati x Basmati **± **± ** S. NO Table Gene effects for head rice recovery Cross Components m d h i l 1 BPT 5204 x Akshyadhan 50.67**± **± **± **± **± BPT 5204 x Pusa **± **± **± **± **± BPT 5204 x Sumathi 53.30**± **± **± **± *± Akshyadhan x NLR **± **± **± **± **± Akshyadhan x Pusa **± **± **± **± **± NLR 145 x Sumathi 52.70**± **± **± **± **± RNR 2354 x I.P Basmati 48.77**± **± **± **± **± RNR 2354 x Basmati **± **± **± **± **± Sumathi x I.P Basmati 57.70**± **± **± **± **± I.P Basmati x Basmati **± **± **± **± **± 1.94 *Significant at 5 % level, ** Significant at 1 % level

206 Table Top ranking desirable crosses for sca effects with their per se performance, heterobeltiosis and inbreeding depression for each of fourteen characters Character and Crosses Predominant gene action Days to 50 per cent flowering Non - additive gca effects of the parents values of sca effects per se performance Heterobeltiosis Inbreeding depression Pusa 1121 x Sumathi high x high NLR 145 x I.P. Basmati low x average Pusa 1121 x I.P. Basmati high x average Akshyadhan x NLR 145 high x low Akshyadhan x RNR 2354 high x average Plant height Non - additive Pusa 1121 x Sumathi average x low RNR 2354 x Sumathi high x low Pusa 1121 x Basmati 370 high x average BPT 5204 x Basmati 370 high x average Akshyadhan x Pusa 1121 low x average Number of productive tillers per Non additive NLR l 145 x Basmati 370 average x low Pusa 1121 x Basmati 370 high x low Akshyadhan x I.P. Basmati average x low BPT 5204 x I.P. Basmati high x low BPT 5204 x NLR 145 high x average Panicle length Non - additive BPT 5204 x Pusa 1121 low x average Sumathi x I.P. Basmati high x high Pusa 1121 x RNR 2354 average x average RNR 2354 x Sumathi average x high NLR 145 x Pusa 1121 low x average Cont.

207 Table 4.14 (Cont.) Character and Crosses Predominant gene action gca effects of the parents values of sca effects per se performance Heterobeltiosis Inbreeding depression Panicle weight Non - additive Akshyadhan x Pusa 1121 high x low BPT 5204 x NLR 145 high x low Akshyadhan x Basmati 370 high x low Akshyadhan x Sumathi high x low BPT 5204 x Improved Pusa Basmati high x low Number of filled grains per panicle Non - additive Pusa 1121 x Sumathi low x high RNR 2354 x I.P. Basmati high x low BPT 5204 x Akshyadhan average x high Akshyadhan x NLR 145 high x low RNR 2354 x Basmati 370 high x average grain weight Non - additive NLR 145 x Pusa 1121 high x high Akshyadhan x Pusa 1121 high x high RNR 2354 x I.P. Basmati low x average NLR 145 x I.P. Basmati high x average NLR 145 x Basmati 370 high x average Grain yield Non additive BPT 5204 x Pusa 1121 high x low BPT 5204 x Akshyadhan high x high Sumathi x I.P. Basmati high x low RNR 2354 x I.P. Basmati average x low I.P. Basmati x Basmati 370 low x high Kernel length Non - additive Pusa 1121 x Sumathi high x high BPT 5204 x Sumathi low x high Akshyadhan x I.P. Basmati average x high BPT 5204 x Basmati 370 low x high NLR 145 x Basmati 370 average x high Cont.

208 Table 4.14 (Cont.). Character and Crosses Predominant gene action Kernel breadth Non - additive gca effects of the parents values of sca effects per se performance Heterobeltiosis Inbreeding depression BPT 5204 x RNR 2354 high x average BPT 5204 x Basmati 370 high x average NLR 145 x Basmati 370 low x average Pusa 1121 x Basmati 370 low x average NLR 145 x Sumathi low x average Kernel L/B ratio Non - additive Pusa 1121 x Sumathi high x high BPT 5204 x Basmati 370 low x high Akshyadhan x I.P. Basmati average x high NLR 145 x Basmati 370 average x high BPT 5204 x Sumathi low x high Kernel length after cooking Non - additive Akshyadhan x NLR 145 average x low Akshyadhan x Basmati 370 average x high Pusa 1121 x Sumathi low x high BPT 5204 x RNR 2354 low x average Akshyadhan x I.P. Basmati average x high Kernel elongation ratio Non - additive BPT 5204 x RNR 2354 average x high Sumathi x Basmati 370 low x high Akshyadhan x NLR 145 average x average Akshyadhan x Basmati 370 average x high BPT 5204 x NLR 145 average x average Head rice recovery Non - additive BPT 5204 x NLR 145 average x high RNR 2354 x Sumathi low x average Pusa 1121 x RNR 2354 low x low NLR 145 x Sumathi high x average

209 Table Top ranking desirable parents for gca with their per se performance for each of fourteen characters S. Character Parent gca effects No 1. Days to 50% flowering Pusa 1121 Sumathi Basmati Plant height BPT 5204 Improved Pusa Basmati NLR Number of productive Pusa tillers/plant BPT Panicle length Akshyadhan Sumathi Improved Pusa Basmati 5. Panicle weight Akshyadhan BPT Number of filled grains/panicle Sumathi RNR 2354 Akshyadhan grain weight Akshyadhan Pusa 1121 Sumathi 8 Grain yield Akshyadhan Basmati 370 BPT Kernel length Pusa 1121 Sumathi Improved Pusa Basmati 10. Kernel breadth Improved Pusa Basmati BPT Kernel L/B ratio Pusa 1121 Sumathi Improved Pusa Basmati 12. Kernel length after cooking Improved Pusa Basmati Basmati 370 Sumathi 13. Kernel elongation ratio RNR 2354 Improved Pusa Basmati Basmati Head rice recovery Akshyadhan NLR

210 Table Promising general combiners for yield and quality characters S. No. Parents Characters Yield 1. Akshyadhan Days to 50% flowering, panicle length, panicle weight/plant, number of filled grains/panicle, 1000 grain weight, grain yield, head rice recovery. 2. Sumathi Days to 50% flowering, panicle length, number of filled grains/panicle, 1000 grain weight, grain yield 3. BPT 5204 Plant height, number of productive tillers/plant, panicle weight/plant, grain yield 4. Basmati 370 Days to 50% flowering, plant height, panicle length, grain yield Quality 1. Improved Pusa Basmati Kernel Length, kernel breadth, kernel L/B ratio, kernel length after cooking, kernel elongation ratio. 2. Basmati 370 Kernel Length, kernel L/B ratio, kernel length after cooking, kernel elongation ratio. 3. Sumathi Kernel Length, kernel L/B ratio, kernel length after cooking Yield and Quality 1. Sumathi Days to 50% flowering, panicle length, number of filled grains/panicle, 1000 grain weight, grain yield, Kernel Length, kernel L/B ratio, kernel length after cooking 2. Basmati 370 Days to 50% flowering, plant height, panicle length, grain yield, Kernel Length, kernel L/B ratio, kernel length after cooking, kernel elongation ratio.

211 Table Promising crosses based on sca effects, per se performance and heterosis for yield and yield contributing characters in rice. S. No. Cross Characters 1 BPT 5204 x Akshyadhan 2 BPT 5204 x Pusa Sumathi x Improved Pusa Basmati 4 RNR 2354 x Improved Pusa Basmati 5 Improved Pusa Basmati x Basmati NLR 145 x Sumathi 7 Akshyadhan x Pusa Akshyadhan x NLR 145 Number of productive tillers/plant, number of filled grains/panicle and grain yield per plant. Panicle length, number of filled grains/panicle and grain yield per plant Days to 50% flowering, panicle length, 1000 grain weight and grain yield per plant Days to 50% flowering, panicle length, number of filled grains/panicle, grain yield per plant and kernel breadth Days to 50% flowering, number of productive tillers/plant, panicle weight/plant and grain yield per plant Days to 50% flowering, number of productive tillers/plant, 1000 grain weight, grain yield per plant, kernel breadth and head rice recovery. Days to 50% flowering, panicle length, panicle weight/plant, 1000 grain weight and grain yield per plant Days to 50% flowering, number of filled grains/panicle, grain yield per plant and kernel length after cooking.

212 Table Genetic parameters (cross wise) in 11 promising crosses with low inbreeding depression. Plant height PCV (%) GCV (%) h 2 (broad sense) (%) GA (%) Akshyadhan x NLR Akshyadhan x RNR NLR 145 x Sumathi Sumathi x Basmati No. of productive tillers/plant PCV (%) GCV (%) h 2 (broad sense) (%) GA (%) Akshyadhan x NLR Akshyadhan x RNR NLR 145 x Sumathi Sumathi x Basmati Panicle length PCV (%) GCV (%) h 2 (broad sense) (%) GA (%) Akshyadhan x NLR Akshyadhan x RNR NLR 145 x Sumathi Sumathi x Basmati Panicle weight/plant PCV (%) GCV (%) h 2 (broad sense) (%) GA (%) Akshyadhan x NLR Akshyadhan x RNR NLR 145 x Sumathi Sumathi x Basmati No. of filled grains/panicle PCV (%) GCV (%) h 2 (broad sense) (%) GA (%) Akshyadhan x NLR Akshyadhan x RNR NLR 145 x Sumathi Sumathi x Basmati grain weight PCV (%) GCV (%) h 2 (broad sense) (%) GA (%) Akshyadhan x NLR Akshyadhan x RNR NLR 145 x Sumathi Sumathi x Basmati Cont.

213 Table 4.64 (Cont.) Grain yield per plant PCV (%) GCV (%) h 2 (broad sense) (%) GA (%) Akshyadhan x NLR Akshyadhan x RNR NLR 145 x Sumathi Sumathi x Basmati Kernel length PCV (%) GCV (%) h 2 (broad sense) (%) GA (%) NLR 145 x Sumathi Sumathi x Basmati Akshyadhan x Pusa Akshyadhan x Imp. Pusa Basmati NLR 145 x Pusa Pusa 1121 x Sumathi Pusa 1121 x Imp. Pusa Basmati Sumathi x Imp. Pusa Basmati Imp. Pusa Basmati x Basmati Kernel breadth PCV (%) GCV (%) h 2 (broad sense) (%) GA (%) NLR 145 x Sumathi Sumathi x Basmati Akshyadhan x Pusa Akshyadhan x Imp. Pusa Basmati NLR 145 x Pusa Pusa 1121 x Sumathi Pusa 1121 x Imp. Pusa Basmati Sumathi x Imp. Pusa Basmati Imp. Pusa Basmati x Basmati Kernel L/B ratio PCV (%) GCV (%) h 2 (broad sense) (%) GA (%) NLR 145 x Sumathi Sumathi x Basmati Akshyadhan x Pusa Akshyadhan x Imp. Pusa Basmati NLR 145 x Pusa Pusa 1121 x Sumathi Pusa 1121 x Imp. Pusa Basmati Sumathi x Imp. Pusa Basmati Imp. Pusa Basmati x Basmati Cont.

214 Table 4.64 (Cont.). Kernel length after cooking PCV (%) GCV (%) h 2 (broad sense) (%) GA (%) NLR 145 x Sumathi Sumathi x Basmati Akshyadhan x Pusa Akshyadhan x Imp. Pusa Basmati NLR 145 x Pusa Pusa 1121 x Sumathi Pusa 1121 x Imp. Pusa Basmati Sumathi x Improved Pusa Basmati Imp. Pusa Basmati x Basmati Kernel elongation ratio PCV (%) GCV (%) h 2 (broad sense) (%) GA (%) NLR 145 x Sumathi Sumathi x Basmati Akshyadhan x Pusa Akshyadhan x Imp. Pusa Basmati NLR 145 x Pusa Pusa 1121 x Sumathi Pusa 1121 x Imp. Pusa Basmati Sumathi x Improved Pusa Basmati Imp. Pusa Basmati x Basmati

215 Chapter V SUMMARY AND CONCLUSIONS The present investigation on Genetic analysis of quantitative traits in aromatic rice (Oryza sativa L.) was undertaken to estimate the extent of heterosis, combining ability, heritability, correlations and path coefficients for grain yield, yield contributing characters and grain quality characters involving both aromatic and non aromatic parents. Further, through generation mean analysis, the nature and magnitude of gene effects were investigated on different quantitative characters. Eight parental lines viz., BPT 5204, Akshyadhan, NLR 145, PUSA 1121, RNR 2354, Sumathi, Improved Pusa Basmati and Basmati 370 were crossed in 8 x 8 diallel design to produce 28 crosses (without reciprocals) at Agricultural Research Station, Kampasagar during kharif, 2011 (June November). During rabi (December May), selfed seed was obtained for all the 28 crosses by advancing F 1 generation and during kharif 2012 all the 28 F 1 s and their corresponding F 2 s and parents were evaluated at a time for combining ability, heterosis and inbreeding depression. The data was generated on eight yield characters (days to 50% flowering, plant height, no. of productive tillers/plant, panicle length, panicle weight, no. of filled grains/panicle and 1000 grain weight), four physical quality (kernel length, kernel breadth, kernel L/B ratio and head rice recovery) and two cooking quality parameters (kernel length after cooking and kernel elongation ratio) apart from final grain yield per plant. During kharif 2012, the same parents (eight) were again crossed for making ten selective independent crosses viz., BPT 5204 x Akshyadhan, BPT 5204 x Pusa 1121, BPT 5204 x Sumathi, Akshyadhan x NLR 145, Akshyadhan x Pusa 1121, NLR 145 x Sumathi, RNR 2354 x Improved Pusa Basmati, RNR 2354 x Basmati 370, Sumathi x Improved Pusa Basmati and Improved Pusa Basmati x Basmati 370 to study generation mean analysis. Five generations viz., P 1, P 2, F 1, F 2, and F 3 of these ten cross combinations were raised during rabi and mean values were utilized for generation mean analysis. Analysis of variance revealed the presence of sufficient variation in the experimental material.

216 Combining ability analysis indicated the preponderance of non-additive gene action with respect to days to 50 per cent flowering, plant height, number of productive tillers per plant, panicle weight, number of filled grains per panicle, grain yield per plant, kernel length, kernel breadth, kernel L/B ratio, kernel length after cooking, kernel elongation ratio and head rice recovery and the role of additive gene effects for panicle length and 1000 grain weight. The parents, Akshyadhan, Sumathi and Basmati 370 were proven to be good combiners for grain yield as well as their prime component traits like panicle length, panicle weight, filled grains per panicle and 1000 grain weight. Whereas, Improved Pusa Basmati and Basmati 370 combined well for kernel characters including cooking quality traits which otherwise were the poor combiners for grain yield. As such the parents, Akshyadhan, Basmati 370 for improving grain yield and Improved Pusa Basmati and Basmati 370 for improving quality were given the best option for breeding material generation. Among the crosses evaluated, Pusa 1121 x Sumathi (for days to 50% flowering), BPT 5204 x Basmati 370 (Plant height), Pusa 1121 x Basmati 370 and BPT 5204 x NLR 145 (no. of productive tillers/plant), Sumathi x Improved Pusa Basmati and RNR 2354 x Sumathi (panicle length), BPT 5204 x Akshyadhan and RNR 2354 x Basmati 370 (no. of filled grains per panicle), NLR 145 x Pusa 1121 and Akshyadhan x Pusa 1121 (1000 grain weight and panicle weight), Pusa 1121 x Sumathi (kernel length and kernel L/B ratio), BPT 5204 x RNR 2354 and BPT 5204 x Basmati 370 (kernel breadth), Pusa 1121 x Sumathi and Akshyadhan x Improved Pusa Basmati (kernel L/B ratio) were identified as the best specific crosses in view of their high per se performance, sca effects and gca of their respective parents (high x high or high x medium). For improvement of panicle length, bi parental matings would be highly feasible as the superior crosses involved the parents having either high x low or low x high gca effects. High heterosis in F 1 generation was accompanied by high inbreeding depression in F 2 generation for the prime yield component, filled grains per panicle, whereas, at the same time, the inbreeding depression was low for panicle weight and 1000 grain weight. Hence, direct selection for yield improvement through these two characters would be highly beneficial. In similar lines, BPT 5204 x RNR 2354 and Akshyadhan x Basmati 370 were identified as best crosses for development of pure lines with good cooking qualities.

217 Superior crosses with high per se performance, sca effects for yield also exhibited high sca effects, significant heterosis and superiority at least for 2-3 component characters viz., BPT 5204 x Akshyadhan (for number of productive tillers/plant, no. of filled grains/panicle and grain yield per plant), BPT 5204 x Pusa 1121 (for panicle length, number of filled grains/panicle and grain yield per plant), Sumathi x Improved Pusa Basmati (for days to 50% flowering, panicle length, 1000 grain weight and grain yield per plant), RNR 2354 x Improved Pusa Basmati (for days to 50% flowering, panicle length, number of filled grains/panicle, grain yield per plant and kernel breadth) and Improved Pusa Basmati x Basmati 370 (for days to 50% flowering, number of productive tillers/plant, panicle weight/plant and grain yield per plant). Heterosis and inbreeding depression studies revealed presence of significant heterosis over mid and better parents in many cross combinations. The crosses BPT 5204 x Pusa 1121 (panicle length and panicle weight), BPT 5204 x Akshyadhan (number of productive tillers/plant and panicle weight) and RNR 2354 x Improved Pusa Basmati (panicle weight, number of filled grains/panicle and 1000 grain weight) exhibited highly significant heterosis and heterobeltiosis for yield and its important component characters besides earliness. The other crosses viz., RNR 2354 x Improved Pusa Basmati, Sumathi x Improved Pusa Basmati and Akshyadhan x Improved Pusa Basmati exhibited significant heterosis for yield and yield contributing characters in addition to important grain quality traits like kernel length and L/B ratio. Significant heterosis coupled with low inbreeding depression was observed in one cross viz., Akshyadhan x Pusa 1121, as such, this particular cross could be made use for development of high yielding pure lines with aroma. The C and D scaling tests and the joint scaling test (3 parameter model) indicated that the additive dominance model was inadequate to explain the inheritance of these characters. Keeping in view the presence of non allelic interactions, the components viz., m, d, h, i and l were estimated using five parameter model (assuming digenic interactions). Based on the magnitudes of fixable genetic variation ( d & i types) and per se, pedigree selection in segregating generations with respect to crosses, BPT 5204 x Sumathi, RNR 2354 x Basmati 370 and Sumathi x Improved Pusa Basmati (for yield and quality) and BPT 5204 x Akshyadhan, Akshyadhan x NLR 145, Akshyadhan x Pusa 1121 (for grain yield) and BPT 5204 x Pusa 1121, Improved Pusa Basmati x Basmati 370 (for quality alone) was recommended.

218 Significant genetic variation in various component characters was observed among the crosses and phenotypic variance was higher than genotypic variance for all the characters thus indicating the influence of environment on these traits. In F 2 generation, among the yield characters, highest PCV and GCV values were recorded for no. of filled grains/panicle followed by grain yield per plant and the lowest for days to 50% flowering and grain quality characters. Highest PCV and GCV values were recorded for head rice recovery and lowest for kernel breadth. High heritability in narrow sense along with medium to high genetic advance was noticed for the traits, days to 50% flowering, 1000 grain weight and most of the kernel traits, which facilitates direct selection / inter-mating of superior genotypes in segregating population (F 2 ) developed from recombination breeding. In F 3 population, higher magnitudes of PCV and GCV were recorded for no. of filled grains/panicle and panicle weight indicating greater scope of obtaining high selection response for these traits. High estimates of heritability in broad sense with moderate genetic advance were recorded for the yield components viz., panicle length, filled grains per panicle and 1000 grain weight and kernel traits viz., kernel length and L/B ratio, which suggested that additive genetic effects played greater role. As such, the chances of obtaining desirable segregants with good yield potential and quality are very bright through pedigree selection. The above discussions were made treating F 2 and F 3 generations as two different populations. As the back crosses were not available in the present study, the inbreeding depression was taken as one criteria to judge the presence of additive genetic variation. As population/ character with high heterosis and less inbreeding depression is considered to be under the control of additive gene effects, 11 crosses with high per se performance, heterosis coupled with less inbreeding depression were carefully choosen and genetic parameters viz., GCV, PCV, h 2 (bs) and GA) were estimated to suggest suitable breeding strategy. The cross which exhibited superior performance for yield and its components had poor expression for quality traits and vice versa. Keeping in view a good amount of variability, high estimates of heritability and expected genetic advance, direct selection for yield improvement in two crosses viz., Sumathi x Basmati 370 and Akshyadhan x NLR 145 and for quality improvement in five crosses viz., NLR 145 x Pusa 1121, Pusa 1121x Sumathi, Pusa 1121x Improved Pusa Basmati, Sumathi x Improved Pusa Basmati and Improved Pusa Basmati x Basmati 370 was considered as highly feasible and recommended. However, direct selection for kernel

219 elongation ratio with respect to only one cross (Sumathi x Improved Pusa Basmati) may not be much rewarding due to low heritable variation. A critical analysis of both character association and path analysis in F 1, F 2 and F 3 indicated that, among the yield components investigated, panicle weight and no. of filled grains/panicle are very important, as the correlation coefficients as well as the direct effects were high irrespective of the generation. Another important character to be considered simultaneously for high yield is panicle length. The results obtained in the present set of materials revealed that the nature and magnitude of gene effects differ depending on the cross and character under consideration. Hence, specific breeding strategy has to be adopted for a particular cross to get improvement in grain yield and its attributing traits in rice. Besides direct selections in some identified crosses, recurrent selection or biparental mating in early segregating generations is also recommended to poolup desired genes depending on the cross combinations to develop potential rice varieties with good quality and aroma. Taking into consideration the whole genetic analysis of the present investigation, pedigree selection in the cross combinations, Akshyadhan x Pusa 1121, NLR 145 x Pusa 1121 and BPT 5204 x NLR 145 for grain yield and Akshyadhan x Improved Pusa Basmati and Pusa 1121 x Sumathi for kernel dimensions (length, L/B ratio) and BPT 5204 x RNR 2354 and Akshyadhan x Basmati 370 for cooking quality characters was considered as most feasible and rewarded. In respect of other superior crosses, instead of direct selection, bi parental matings in F 2 generation followed by selection was recommended.

220 LITERATURE CITED Aananthi, N and Jebaraj, S Heterosis in two line rice hybrids. Indian Journal of Agriculture Research. 40 (3): Abd-Allah., Soheir, M.H and Amin, I.A Genotypic differences for heat tolerance traits in bread wheat using five parameters genetic model. Alexandria Journal of Agricultural Research. 58 (2): Adilakshmi, D and Raghava Reddy, P The Andhra Agricultural Journal. 58 (2): Ahmad, B.B.H., Gupta, S.M., Razvi, M., Bhat, S.A., Najeeb Wani, Bhat, A.N and Mir, M.R Cause and effect relations of morpho-agronomic and physiobiochemical traits of important rice (Oryza sativa L.) varieties under subtropical conditions of Jammu. International Journal of Current Research. (2): Ahmadikhah, A Study on selection effect, genetic advance and genetic parameters in rice. Annals of Applied Biology. 1 (4): Ahmed, M.A and Mehra, R.B Genetic characterization of Gossypium hirsutum cross Pusa x Pusa Indian Journal of Genetics. 60 (4): Ahmad H., Razvi S.M., Ashraf Bhat A., Najeeb S., Wani N., Habib M., Mir M.R. and Gupta B.B Genetic variability and genetic divergence of important rice (Oryza sativa L.) varieties. International Journal of Current Research. 4: Akhtar, N., Nazir, M. F., Rabnawaz, A., Mahmood, T., Safdar, M. E., Asif, M and Rehman, A Estimation of heritability, correlation and path coefficient analysis in fine grain rice (Oryza sativa L.). The Journal of Animal & Plant Sciences. 21 (4): Akinwale, M.G., Gregorio, G., Nwilene, F., Akinyele, B.O., Ogunbayo, S.A and Odiyi, A.C Heritability and correlation coefficient analysis for yield and its components in rice (Oryza sativa L.). African Journal of Plant Science. 5 (3): Alam, A. F., Khan, R., Nuruzzaman, M., Parvez, S., Swaraz, A.M., Alam, I and Ahsan, N Genetic basis of heterosis and inbreeding depression in rice (Oryza sativa L). Journal of Zhejiang University Science. 5 (4):

221 Ali, S.S., Jafri, S., Khan, T.Z., Mahmood, A. and Butt, M.A Heritability of yield and yield components of rice. Pakistan Journal of Agricultural Research. 16 (2): Allahgholipour, M and Ali, A.J Gene action and combining ability for grain yield and its components in rice. Journal of Sustainable Agriculture. 28 (3): Allard, R. W Principles of Plant Breeding. John Wiley and Sons Inc., New York, USA Anand Kumar, Singh, N. K and Sharma, V. K Combining ability analysis for identifying elite parents for heterotic rice hybrids. Oryza 43 (2): Anand, G., Amirthadevarathinam, A and Edwin Rogbell Combining ability and heterosis for cold tolerance in rice. Oryza. 36 (2): Ananda Kumar, C. R and Sreerangaswamy, S.R Heterosis and inbreeding depression in rice. Oryza. 23: Ananda Kumar, C. R Variability and character association studies in upland rice. Oryza. 29: Ananadarao.S.D., Singh, C.M., Suresh, B.G and. Lavanya, G.R Evaluation of rice hybrids for yield and yield component characters under North east plain Zone. The Allahabad Farmer. 67 (1): Anbanandan, V., Saravanan, K and Sahesan, T Variability, heritability and genetic advance in rice. International Journal of Plant Sciences. 4 (1): Anbumalarmathi, J and Nadarajan, N Association analysis of yield and drought tolerant characters in rice (Oryza sativa L.) under drought stress. Agriculture Sciences Digest. 28 (2): Anil Kumar and Mani, S.C Gene action for grain yield, its components and quality traits in Basmati rice (Oryza sativa L). Pantnagar Journal of Research. 8 (1): Anjaneyulu, M., Reddy, D.R. and Reddy, K.H.P Genetic variability, heritability and genetic advance in rice (Oryza sativa L.). Research on Crops. 11: Anju Chaudhary., Pankaj Sharma., Harpal Singh., Pradhan, S.K and Pandey, M.P Study on heterosis for yield and physiological characters in rice hybrids. Oryza. 44 (1): 7-13.

222 Annadurai, A and Nadarajan, N Heterosis for yield and its component traits in rice. Madras Agricultural Journal. 88 (1-3): Asfaliza, R., Rafii, M.Y., Saleh, G., Omar, O and Puteh, A Combining ability and heritability of selected rice varieties for grain quality traits. Australian Journal of Crop Science. 6 (12): Asha Christopher, Jebarai, S and Backiyarani, S Interrelationship and path analysis of certain cooking quality characters in heterogenous populations of rice (Oryza sativa L.). Madras Agricultural Journal. 86 (4-6): Ashfaq, M., Haider, M. S., Khan, A. S and Allah, S. U Heterosis studies for various morphological traits of basmati rice germplasm under water stress conditions. The Journal of Animal & Plant Sciences. 23 (4): Ashok Kumar Tuwar., Singh, S. K., Amita Sharma and Bhati, P. K Appraisal of genetic variability for yield and its component characters in rice (Oryza sativa L.) Biolife. 1 (3): Ashrafuzzaman, M., Islam M.R., Ismail M.R., Shahidullah S.M. and Hanafi M.M Evaluation of six aromatic rice varieties for yield and yield contributing characters. International Journal of Agricultural and Biological Engineering. 11(5): Awasthi, L.P and Pandey, V.K Genetic variation in morphological traits of aromatic rice. Crop Research Hisar. 19 (2): Awasthi, R.P and Borthakur, D.N Agronomic evaluation of rice varieties in upland terraces of Meghalaya. Indian Journal of Agricultural Sciences. 56 (10): Babar, M., Khan, A.A., Arif, A., Zafar, Y and Arif, M Path analysis of some leaf and panicle traits affecting grain yield in doubled haploid lines of rice (Oryza sativa L.). Journal of Agricultural Research. 45 (4): Babu, M.S., Satyanarayana, P.V., Madhuri, J and Kumar, R.V Combining ability analysis for identifying elite parents for heterotic rice hybrids. Oryza. 37 (1): Bagheri, N., Jelodar, N.B and Ghanbari, A Diallel analysis study of yield and yield-related traits in rice genotypes. International Journal of Agricultural Research. 3:

223 Bala, A Genetic variability, association of characters and path coefficient analysis of saline and alkaline rice genotypes under rainfed condition. Madras Agricultural Journal. 88 (4-6): Balan, A., Muthaiah and Ramachandra Boopathi, S.N.M Genetic variability, correlation and path coefficient analysis in upland early rice genotypes. Madras Agricultural Journal. 86 (1-3): 7-9. Bansal, U.K., Saini, R.G and Rani, N.S Heterosis and combining ability for yield, its components, and quality traits in some scented rices (Oryza Sativa L.). Tropical Agriculture. 77 (3): Banumathy, S and Prasad, M.N Studies of combining ability for development of new hybrids in rice. Oryza. 28: Banumathy, S and Thiyagarajan, K Genetic analysis of yield traits in rice. Crop Research. 30 (2): Banumathy, S., Thiyagarajan, K and Vaidyanathan, P Combining ability for yield and yield components in three line hybrid rice. Oryza. 40 (3&4): Basavaraja, T., Gangaprasad, S., Dhusyantha Kumar, B.M and Shilaja Hittlamani Correlation and path analysis of yield and yield attributes in local rice cultivars (Oryza sativa L.). Electronic Journal of Plant Breeding. 2 (4): Bateson, W Mendel s principles of heredity: A Defense. The University Press, Cambridge. Bhadru, D., Krishna, L., Latheef Pasha, Md and Muralidhar Naik, R.B Effect of environment on genetic parameters of hybrid rice. International Journal of Applied Bilogy and Pharmaceutical Technology. 3 (2): Bhandarkar, S., Rastogi, N. K and Arvindkumar Study of heterosis in rice (Oryza sativa L.). Oryza. 42 (3): Bharadwaj, C., Rajesh Mishra., Satyavathi, C. T., Rao, S. K and Kumar, K. S Genetic variability, heritability and genetic advance in some new plant type based crosses of rice. Indian Journal of Agricultural Research. 41 (3): Bhatti, M. A., Azhar, F.M and Alwi, A.W Estimation of additive, dominance and epistatic components of genetic variation in fiber quality characters of up-land cotton grown in salinized conditions. International Journal of Agriculture and Biology. 8 (6):

224 Bhave, S.G., Dhonukshe, B.L., and Bendale, V.W Heterosis in hybrid rice. Journal of Soils and Crops. 12: Bhawana Joshi, Singh, H and Pandey, M.P Study of heterosis and inbreeding depression in rice. Oryza. 41 (3&4): Bidhan Roy and Mandal, A.B Combining ability of some quantitative traits in rice. Indian Journal of Genetics and Plant Breeding. 61 (2): Bisne, R and Motiramani, N.K Study on gene action and combining ability in rice. Oryza. 42 (2): Bisne, R., Sarawgi, A.K. and Verulkar, S.B Study of heritability, genetic advance and variability for yield contributing characters in rice. Bangladesh Journal of Agricultural Research. 34 (2): Borah, S.P and Barman, D Heterosis for yield components in inter-mutant hybrids of rice. Oryza. 47 (1): Borbora, T. K and Hazarika, G.N Study of genetic variability, heritability and genetic advance for panicle characters in rice. Oryza. 35 (1): Borbora, T.K., Hazarika, G.N and Medhi, A.K Correlation and path analysis for plant and panicle characters in rice (Oryza sativa L.). Crop Research. 30 (2): *Burton, G.W Quantitative inheritance in grasses. Proceedings on 6 th International Grassland Congress Journal. 1: *Cavalli, L.L An analysis of linkages of quantitative inheritance. Quantitative Inheritance (Ed. E. C. R. Reive and C.H. Waddington), HMSO, London: Chakraborthy, S., Hazarika, M.H and Hazarika, G.N Combining ability analysis in rice. Oryza. 31: Chakraborty, R and Chakraborty, S Genetic variability and correlation of some morphometric traits with grain yield in bold grained rice (Oryza sativa L.) gene pool of Barak valley. American-Eurasian Journal of Sustainable Agriculture. 4 (1): Chandra Kishore., Yogendra Prasad., Haider, Z.A., Ravi Kumar and Kamleshwar Kumar Quantitative analysis of upland rice. Oryza. 45 (4):

225 Chang, Te-Tzu., Cheng Chang, Li and Oscar Tagumpay Genotypic correlation, heterosis, inbreeding depression and transgressive segregation of agronomic traits in a diallel cross of rice (Oryza sativa L.) cultivars. Botanical Bulletin of Academia Sinica. 14: Chaubey, P.K and Richharia, A.K Genetic variability, correlations and path coefficients. Indian Journal of Genetics. 53 (4): Chaubey, P.K and Singh, R.P Genetic variability, correlation and path analysis of yield components in rice. Madras Agricultural Journal. 81 (9): Chaudhary, R.C Speciality rices of the world: Effect of WTO and IPR and on its production trend and marketing. Journal of Food Agriculture and Environment. 1: Chaudhary, M and Motiramani, N. K Variability and association among yield attributes and grain quality in traditional aromatic rice accessions. Crop Improvement. 30 (1): Chauhan, J.S and Chauhan, V.S Heterosis and Inbreeding depression in rainfed rice. Indian Journal of Agricultural Sciences. 64: Chauhan, J.S Genotypic and phenotypic correlations between grain yield and associated characters in very early duration elite breeding cultures of rice. Oryza. 33: Chawla, H.S and Gupta, V.P Combining ability analysis of oxalic acid, minerals and green fodder yield in pearl millet. Theory and Applied Genetics. 61: Chikkalingaiah Shridhara S., Lingaraju, S and Radhakrishna, R.M Genetic variability of plant and quality traits in promising genotypes of scented rice (Oryza sativa L.). Mysore Journal of Agricultural Sciences. 33 (4): Chitra, S., Ananda Kumar, C.R and Vivekanandan, P Correlation and path analysis Assam Rice Collection (Oryza sativa L.). The Andhra Agriculture Journal. 52 (3&4): Chookar, S.K., Marekar, R.V and Siddiqui, M.A Genetic variability for grain yield and yield contributing characters in rice. Journal of Maharashtra Agricultural Universities. 19 (2):

226 CMIE Executive Summary. Centre for Monitoring Indian Economy (CMIE) Pvt. Ltd. Mumbai. Cockerham, C.C Implication of genetic variance in a hybrid breeding programme. Crop Science. 1: Dalvi, V.V. and Patel, D.U Combining ability analysis for yield in hybrid rice. Oryza. 46 (2): Datt, S and Mani, S.C Heterosis for yield and grain dimensions in basmati rice (Oryza sativa L.). Oryza. 41 (1&2): 4-7. De, D.K., Pal, S.K., Ghosh, M and Pal, A.K Correlation and path analysis in aromatic rice. Annals of Agricultural Research. 26 (3): De, R.N and Suriya Rao, A.V Genetic variability and correlation studies in rice under semi-deep waterlogged situation. Oryza. 25: Deb Choudhury, P.K and Das, P.K Genetic variability, correlation and path coefficient analysis in deep water rice. Annals of Agricultural Research. 19 (2): Deoraj., Singh, D.N., Madhuviarya and Praveen Singh Heterosis in rainfed transplanted rice. Oryza. 44 (3): Deosarkar, D. B., Missal, M.B and Nerkar, Y.S Variability and correlation studies for grain quality characters in breeding lines of Rice. Journal of Maharashtra Agricultural Universities. 14 (1): Devi, S.L., Raina, F.A. Pandey, M.K. and Cole, C.R Genetic parameters of variation for grain yield and its components in rice. Crop Research. 32 (1): *Dewey, O.R and Lu, K.H Correlation and path coefficient analysis of components of crested wheat grass seed production. Journal of Agronomy. 51: Dey, S.R., Bhuyan, M.S.R., Maniruzzaman, M., Islam, M.A and Begum, S Heterosis in inter-ecotypic classes of rice (Oryza sativa L.). Journal of Agroforestry Environment. 7 (1): Dhakar, J.M and Vinit Vyas Combining ability analysis in rice (Oryza sativa L.). Crop Research. 31 (3):

227 Dhanakodi, C.V and Subramanian, M Genetic analysis of yield components in short duration rice (Oryza sativa L.) varieties. Madras Agricultural Journal. 81 (7): Dhanakodi, C.V and Subramanian, M Genetic studies on yield and its component characters in short duration rice varieties. First National Plant Breeding Science Congress, Coimbatore, Abstract pp *Dhankhar, S.K and Dhankhar, B.S Gene action for fruit yield in tomato at high temperature conditions. Haryana Journal of Horticultural Sciences. 31: Dutta, R.K., Baset Mia, M.A and Khanam, S Plant architecture and growth characteristics of fine grain and aromatic rices and their relation with grain yield. International Relations Council News letter. 51: Eidi kohnaki Mostafa, Ghaffar Kiani and Ghorbanali Nematzadeh Relationship between morphological traits in rice restorer lines at F 3 generation using multivariate analysis. Int J Adv Biol Biom Res. 1(6): Eradasappa, E., Ganapathy, K.N., Satish, R.G., Shanthala, J and Nadarajan, N. 2007a. Heterosis studies for yield and yield components using CMS lines in rice (Oryza sativa L.). Crop Research Hisar. 34: Eradasappa, E., Nadarajan, N., Ganapathy, K.N., Shanthala, J and Satish, R.G. 2007b. Correlation and path analysis for yield and its attributing traits in rice (Oryza sativa L.). Crop Research. 34 (1&2): Falconer, D.S Introduction to quantitative genetics. Oliver, Boyd Edinberg, London Falconer, D.S Introduction to quantitative genetics. 2 nd edition. Longman, New York. *Fisher, R.A and Yates, F Statistical tables for biological, agricultural and medical research. Olive Boyd, Edinburgh. Frakes, R.V., Davis, R.L and Patterson, F.L The breeding behaviour of yield and related variables in Alfalfa association between characters. Crop Science. 1:

228 Frey, K. J Breeding approaches for increasing cereal crop yields. Paper presented at the International Rice Research Conference, April, International Rice Research Institute, Philippines. Ganesan, K and Subramanian, M Genetic studies of the F 2 and F 3 of tall x dwarf rice crosses. Madras Agricultural Journal. 81 (1): Ganesan, K.N and Rangaswamy, M Combining ability studies in rice hybrids involving wild abortive (WA) and Oryza perennis sources of CMS lines. Oryza. 35 (2): Ganesan, K., Wilfred Manuel, W., Vivekanandan, P and Armugam, P.M Inbreeding, variability, heritability and genetic advance in F 2 populations derived from early and extra early rice cultivars. Oryza. 33: Ganesan, K., Wilfred Manuel, W., Vivekanandan, P and Arumugam Pillai Character association and path analysis in rice. Madras Agricultural Journal. 84 (10): Gannamani, N Study of heterosis and combining ability by utilizing cytoplasmic genetic male sterility and fertility restoration system in rice (Oryza sativa L.). M. Sc.(Ag.)Thesis. Gujarat Agricultural University, Raipur. Geetha, S and Ayyamperumal, A Heterosis for physio chemical characters in rice. International Rice Research Notes. 22 (3): 5-6. Ghosh, A Combining ability for yield and its related traits in upland rice. Oryza. 30: Ghosh, A Studies on heterosis in upland rice. Oryza. 39: 5-8. Gnana Sekaran, M., Vivekanandan, P and Muthuramu Combining ability and heterosis yield and grain quality in two line rice (Oryza sativa L.) hybrids. Indian Journal of Genetics. 66 (1): 6-9. Gnanamalar, R. P and Vivekanandan, P. 2013a. Combining ability analysis of grain quality traits in rice (Oryza sativa L.). Asian Journal of Plant Science and Research. 3 (2): Gnanamalar, R. P and Vivekanandan, P. 2013b. Heterosis for grain yield and grain quality traits in rice (Oryza sativa L.). Asian Journal of Plant Science and Research. 3 (3):

229 Gnanamalar, R. P and Vivekanandan, P. 2013c. Genetic architecture of grain quality characters in rice (Oryza sativa L.). European Journal of Experimental Biology. 3 (2): Gonya Nayak. P., Sreedhar. M., Surender Raju. Ch., Sumathi. S and Vanisree. S Combining ability analysis involving aromatic lines for grain quality traits in rice (Oryza sativa L.). Journal of Research ANGRAU. 39 (4): Good, B.C and Siddiq, E.A Genetic analysis of crude protein content in rice. Indian Journal of Agricultural Sciences. 56 (11): Gopikannan, M and Ganesh, S. K Inter-relationship and path analysis in rice (Oryza sativa L.) under sodicity. Indian Journal of Science and Technology. 6 (9): Gouri Shankar, V., Ansari, N. A., Ilyas Ahamed, M. and Venkata Ramana Rao, P Heterosis studies using thermo-sensitive genetic male sterile lines in rice. Oryza. 47 (2): Govindarasu, R Analysis of variability and correlation among high density grain characters in rice. Madras Agricultural Journal. 82 (12): Griffing, B Concepts of general and specific combining ability in relation to diallel crossing systems. Australian Journal of Biological sciences. 9: Gulzar, S., Sanghera, Subhash and Kashyap, C Genetic parameters and selection indices in F 3 progenies of hill rice genotypes. Journal of Natural Science, Biology and Medicine. 4 (4): Gupta, J.C., Kotoch, P.C., Kaushik, R.P and Sharma, S.L Cause and effect relationship of yield and its components under cold stress condition in rice (Oryza sativa L). Indian Journal of Agricultural Sciences. 68 (1): Haq, M.I.U., Ajmal, S., Kamal, N., Khanum, S., Sidique, M and Kiani, M.Z Generation mean analysis for grain yield in maize. The Journal of Animal & Plant Sciences. 23 (4): Haque, M.E., Baset, A., Zeenat, Z and Miah, N.M, Path coefficient analysis of seven characters in cold tolerant rice (Oryza sativa L.). Bangladesh Rice Journal. 2: 1-7. Hasib, K.M Genetic variability, interrelations and path analysis for panicle characters in scented rice. Crop Research. 30 (1):

230 Hasib, K.M., Ganguli, P.K and Kole, P.C Genetic analysis of some quantitative characters in aromatic rice involving induced mutants. Tropical Agricultural Research and Extension. 5 (1 & 2): 1-6. Hayman, B.I and Mather, K The description of genetic interaction in continuous variation. Biometrics. 11: Hayman, B.I The separation of epistasis from additive and dominance variation in generation means. Heredity. 12: Honarnejad, R and Tarang, A Gene effect in controlling quantitative traits in rice (Oryza sativa L.). Iranian Journal of Agricultural Sciences. 32 (2): Hooda, J. S., Tomar, Y.S., Vashistha, R.D and Phogat, D.S Generation mean analysis in pigeon pea (Cajanus cajan L.). Annals of Biology. 16 (1): Iftekharudduala, K.M., Hassan, M.S., Islam, M.J., Badshah, M.A., Islam, M.R and Akhter, K Genetic evaluation and selection criteria of hybrids rice in irrigated ecosystem of Bangladesh. Pakistan Journal of Biological Science. 4 (7): Imad Naseem., Abdus Salam Khan and Muhammad Akhter Correlation and path coefficient studies of some yield related traits in rice (Oryza sativa L.). International Journal of Scientific and Research Publications. 4 (4): 1-5. Immanuel Selvaraj, C., Pothiraj Nagarajan., Thiyagarajan, K., Bharathi, M and Rabindran, R Genetic parameters of variability, correlation and path coefficient studies for grain yield and other yield attributes among rice blast disease resistant genotypes of rice (Oryza sativa L.). African Journal of Biotechnology. 10 (17): Iqbal, M.Z and Nadeem, M.A Generation mean analysis for seed cotton yield and number of sympodial branches per plant in cotton (Gossypium hirsutum L.). Asian Journal of Plant Sciences. 2 (4): Islam, M. M., Sarker, U., Rasul, M. G and Rahman M. M Heterosis in local boro rice (Oryza sativa L.). Bangladesh Journal of Plant Breeding and Genetics. 23 (1): Ismail, R.M Genetic analysis of yield and its contributing traits in two intraspecific cotton crosses. Journal of Applied Sciences Research. 3 (12):

231 Janardhan,V., Nadarajan, N and Jebaraj, S. 2001a. Studies on heterosis in rice. Madras Agricultural Journal. 88: Janardhanam, V., Nadarajan, N and Jebaraj, S. 2001b. Correlation and path analysis in rice (Oryza sativa L.). Madras Agricultural Journal. 88: Jayasudha, S and Deepak Sharma Genetic parameters of variability, correlation and path-coefficient for grain yield and physiological traits in rice (Oryza sativa L.) under shallow lowland situation. Electronic Journal of Plant Breeding. 1 (5): Jennings, P.R., Coffman, W.R and Kaufman, M.H.E Grain quality: Rice improvement. International Rice Research institute, Philippines. Chapter, 6: *Jensen, N.F A diallel selective mating system for cereal breeding. Crop Science. 10: Jinks, J.L and Jones, R.M Estimation of the components of heterosis. Genetics. 43: Jinks, J.L The analysis of continuous variation in diallel cross of Nicotiana rustica varieties. Genetics. 39: *Johnson, H.W., Robinson, H.F and Comstock, R.E Estimates of genetic and environmental variability in soybean. Agronomy Journal. 47 (7): *Jones, J.W Hybrid vigour in rice. Journal of American Society for Agronomy. 18: Karad, S.R and Pol, K.M Character association, genetic variability and path coefficient analysis in rice (Oryza sativa L.). International Journal of Agricultural Sciences. 4 (2): Karim, D., Sarkar, U., Siddique, M.N.A., Khaleque Miah, M.A. and Hasnat, M.Z Variability and genetic parameter analysis in aromatic rice. International Journal of Sustainable Crop Production. 2 (5): Kashyap, O.P and Rastogi, N.K An analysis of generation means for seed yield and its components in linseed. Annals of Agricultural Research. 27 (2): Katoch, V and Vidyasagar Genetic studies on yield and its components in tomato. Journal of Applied Horticulture. 6:

232 Kavitha, S and Sree Rama Reddi, N Correlation and path analysis of yield components in Rice. The Andhra Agricultural Journal. 48 (3-4): Kaw, R.N., Aquino, R.C., Moon, H.P., Yae, J.D and Haw, N Variability and inter-relations in rice under cold stress environments. Oryza. 36 (1): 1-4. Khedikar, V.P., Bharose, A.A,, Sharma, D., Khedikar, Y.P and Killare, A.S Path coefficient analysis of yield components of scented rice. Journal of Soils and Crops. 14 (1): Kiani, S.H., Kazemitabar, S.K., Babaeian Jelodar, N.A and Ranjbar, G.A Genetic evaluation of quantitative traits of rice (Oryza sativa L.) using generation mean analysis. International Journal of Agriculture and Crop Sciences. 5 (19): Kishore, N.S., Babu, V.R., Ansari, N.A and Prasad, A.R Genetic variability, heritability and genetic advance in rice (Oryza sativa L.) genotypes of different eco-geographical region. Research on Crops.9 (1): Koodalingam M 1994 Genetics of resistance to gall midge and yield components in medium duration rice (Oryza sativa L.). Ph. D. Thesis. Tamil Nadu Agricultural University, Coimbatore. Krishna Naik, R., Sreenivasulu Reddy, P., Ramana, J.V and Srinivasa Rao, V Correlation and Path Coefficient Analysis in rice (Oryza sativa L.). The Andhra Agriculture Journal. 52 (1&2): Krishna Veni, B and Shobha Rani, N Association and path analysis for yield components in F 2 generation of rice. The Andhra Agriculture Journal. 52 (1&2): Krishna Veni, B and Shobha Rani, N Association of grain yield with quality characteristics and other yield components in rice. Oryza. 43 (4): Krishna, L., Raju, Ch.D and Raju, Ch.S Genetic variability and correlation in yield and grain quality characters of rice germplasm. The Andhra Agriculture Journal. 55 (3): Krishna, L., Raju, D. Ch., Surender Raju, Ch., Vanisree, S., Narsimha Reddy, P and B.B. Reddy, B.B Heterosis for yield and quality traits in rice (Oryza sativa L.). Madras Agricultural Journal. 98 (4-6):

233 Kuldeep, T., Bathshwar Kumar., Ramesh, B and Ajay, J Genetic variability and correlations for some seedling and major plant traits in 70 genotypes of rice. Research on Crops. 5(1): Kumar, P and Ramesh, B Genetic variability and character association in rice. Progressive Agriculture. 8 (2): Kumar, A and Senapati, B.K Genetic parameters and association studies for important quantitative traits in advanced lines of Sambamahsuri derivatives. Journal of Crop and Weed. 9 (1): Kumar, G.S., Mahadevappa, M and Rudraradhya, M Studies on genetic variability, correlation and path analysis in rice during winter across the locations. Karnataka Journal of Agricultural Sciences. 11(1): Kumar Aditya., Singh, S and Singh, S.P Genetic analysis of yield and quality traits in Basmati rice. Oryza. 50 (2): Kumar M., Sharma P.R., Krakash N. and Singh P.K Selection criteria for high yielding genotypes in early generations of rice. SAARC J. Agri.,7(2): Kumar Babu, G., Satyanarayana, P. V., Panduranga Rao, C. and Srinivasa Rao, V Heterosis for yield, components and quality traits in rice (Oryza sativa L.). Andhra Agricultural Journal. 57 (3): *Lakshmikant and Gulati, S.C Inheritance of components of horizontal resistance to Alternaria brassicae (Berk.) Sacc. in Indian mustard (Brassica juncea L.). Journal of Oilseeds Research. 19 (1): Lal Mohan and Chauhan Devendra, K Studies of genetic variability, heritability and genetic advance in relation to yield traits in rice. Agricultural Science Digest. 31 (3): Lavanya, C Combining ability for yield and its components in hybrid rice. Oryza. 37 (1): Leena Kumari, S and Valarmathi, G Relationship between grain yield, grain filling rate and duration of grain filling in rice. Madras Agricultural Journal. 85 (3&4): Li, Z.K., Pinson, S.R.M., Paterson, A.H., Park, W.D., Stansel, J.W Genetics of hybrid sterility and hybrid breakdown in an inter-sub specific rice (Oryza sativa L.) population. Genetics. 145:

234 Liang, G.H., Reddy, C.R and Dayton, A.D Heterosis, inbreeding depression and heritability estimates in a systematic series of grain sorghum genotypes. Crop Science. 12: *Liang, K.J., Yang, R.C., Wang, Y.N and Yan, S.L Analysis of gene effects of quantitative characters in inter sub-specific hybrid rice. Journal of Fujian Agriculture University. 25(1): Lokaprakash, R., Shivashankan, G., Mahadevappa, M., Shankaregowda and Kulkarni, R.S Heterosis in rice. Oryza. 29: Lokaprakash, R., Shivashankan, G., Mahadevappa., Shankaregowda, B.T and Kulkarni, R.S Combining ability for yield and its components in rice. Oryza. 28: Madhavi Latha L 2002 Studies on genetic divergence and isozyme analysis on rice (Oryza sativa L). M.Sc.(Ag.) Thesis. Acharya N. G. Ranga Agricultural University, Hyderabad. Madhavi Latha, L., Sekhar, M.R., Suneetha, Y and Srinivas, T Genetic variability, correlation and path analysis for yield and quality traits in rice (Oryza sativa L.). Research on Crops. 6 (3): Mahalingam, L and Nadarajan, N Genetic analysis of grain quality characteristics of two line rice hybrids. Electronic Journal of Plant Breeding. 1 (4): Mahto, R.N., Yadava, M.S and Mohan, K.S Genetic variation, character association and path analysis in rainfed upland rice. Indian Journal of Dry land Agricultural Research and Development. 18 (2): Malini, N., Sundaram, T and Hari Ramakrishanan, S Studies on cause and effect relationship between yield and its contributing traits in rice (Oryza sativa L.). Crop Research. 34 (1, 2 &3): Mandal, R.K and Sunil Saran Hybrid rice breeding for grain characters. Oryza. 26: Manna, M., Nasim Ali, M.D and Sasmal, B.G Variability, correlation and path coefficient analysis in some important traits of low land rice. Crop Research. 31 (1):

235 Manoj Kumar Prajapati., Chandra Mohan Singh., Suresh Babu, G., Roopa Lavanya, G and Priyadarshini Jadhav Genetic parameters for grain yield and its component characters in rice. Electronic Journal of Plant Breeding. 2 (2): Manonmani, S and Ranganathan, T.B Genetic analysis in early lines of indica rice. Oryza. 35 (4): Manonmani, S and Ranganathan, T.B Path analysis in very early crosses of rice. Oryza. 43 (1): Manonmani, S., Sree Rangasamy, S.R and Ranganathan, B Variability and heritability in early lines of Indian rice. Madras Agricultural Journal. 83 (1): Marimuthu, R., Rajasekharan, S and Soundarapandian, G Variability, heritability and genetic advance in rice. Madras Agricultural Journal. 77: Mather, K and Jinks, J.L Biometrical Genetics. Cornell University Press, Ithaca. 382p. Mather, K and Jinks, J.L Biometrical Genetics, Third edition. Chapman and Hill Ltd. London. Mather, K Biometrical Genetics. Metuen and Co. Ltd., London. Meenakshi, T and Devarathinam, A.A Combining ability for yield and physiological characters in semi dry rice. Oryza. 36 (2): Mishra, M and Pandey, M.P Heterosis breeding in rice for irrigated sub-humid tropics in north India. Oryza. 35 (1): Mishra, L.K., Sarawgi, A.K and Mishra, R.K Genetic diversity for morphological and quality traits in rice (Oryza sativa L.). Advance in Plant Science. 16 (1): Mokate, A.S., Bendale, V.W and Birari, S.P Variability, heritability, correlation and path analysis studies in rice (Oryza sativa L.). Crop Research. 15: 243. Mukeshkumar, Chaudhary, B.S and Singh, J.B Generation mean analysis of some important quantitative characters in gobhi sarson (Brassica napus L.). Journal of Oilseeds Research. 23 (1):

236 Munhot, K.K., Sarawgi, A.K and Rastogi, N.K Gene action and combining ability for yield, grain quality and other related characters in rice. Oryza. 37: 16. *Murthy, P.S.N Genetic studies in rice with special reference to certain quality features. M. Sc. (Botany) Thesis. Orissa University of Agriculture and Technology, Bhubaneshwar. Murthy P.S.N Study of gene action for quality and yield components in rice (Oryza sativa L.). Ph. D Thesis. Acharya N G Ranga Agricultural University, Hyderabad, India. Murthy, P.S.N and Govindaswamy, S Inheritance of grain size and its correlation with the hulling and cooking qualities. Oryza. 4 (1): Murugan, S and Ganesan, J Generation mean analysis in rice (Oryza sativa L.) crosses utilizing WA cytosteriles. Plant Archives. 6 (1): Nagajyothi, B Studies on performance and heterosis of rice hybrids for yield. yield components and certain grain quality characters. M.Sc. (Ag.) Thesis. Acharya N.G. Ranga Agricultural University, Hyderabad, India. Nandan, R., Sweta and Singh, S.K Characters association and analysis in rice (Oryza sativa L.) genotypes. World Journal of Agricultural Sciences. 6 (2): Narasimman, R., Thirugnanakumar, S., Eswaran, R., Praveen, C., Sampath Kumar and Anandan, A Combining ability and heterosis for grain yield and its component characters in rice (Oryza sativa L.). Crop Improvement. 34 (1): Nath, N and Talukdar, P Genetic variability and correlation studies in segregating populations of indigenous Scented x High yielding non-scented crosses of rice. Oryza. 34 (2): Nayak, A.R, Chaudhary, D and Reddy, J.N Correlation and path analysis in scented rice (Oryza sativa L.). Indian Journal of Agricultural Research. 35 (3): Nayak, A.R, Chaudhary, D and Reddy, J.N Genetic variability, heritability and genetic advance in scented rice. Indian Agriculturist. 46 (1&2):

237 Nayak, A.R, Chaudhary, D and Reddy, J.N Genetic variability and correlation study among quality characters in scented rice. Agricultural Science Digest. 23 (3): Nayak, A.R., Chaudhary, D and Reddy, J.N Genetics of yield and yield components in scented rice. Oryza. 44 (3): Nayudu, K.S.R., Varline, Y.A and Vennila, S Studies on variability, heritability and genetic advance for certain yield compounds in rice. Crop Improvement. 34 (2): Niranjana Murthy., Kulkarni, R.S and Uday Kumar, M Genetic variability, heritability and genetic advance for morpho-physiological traits in rice. Oryza. 36 (2): Nivedhitha, M.S., Krishna Veni, B., Rama Kumar, P.V and Srinivasa Rao, V Association analysis for grain yield, yield components and quality parameters in M 3 generation of rice (Oryza sativa L.). The Andhra Agricultural Journal. 60 (4): Nuruzzaman, M., Alam, M.F., Ahmed, M.G., Shohael, M.A., Biswas, M.K., Amim, M.R and Hossain, M.M Studies on parental variability and heterosis in rice. Pakistan Journal of Biological Sciences. 5 (10): Okelola, F.S., Adebisi, M.A., Kehinde, O.B and Oluwole, A.M Genotypic and phenotypic variability for seed vigour traits and seed yield in West African rice (Oryza sativa L.) genotypes. American Journal of Science. 3 (3): Padma Sundari, M., Kamala, T and Rao, Y.V Generation mean analysis in Sesamum indicum L. Asisan Journal of Agricultural Sciences. 4 (4): Padmavathi, N., Mahadevappa, M and Reddy, K Association of various yield components in rice (Oryza sativa L.). Crop Research Hissar. 12: Padmavathi, P.V., Satyanarayan, P.V., Lal Ahamed, M., Ashoka Rani and Srinivas Rao, V Combining ability studies for yield and yield components in hybrid rice (Oryza sativa L.). Electronic Journal of Plant Breeding. 3 (3): Palaniraja, K., Anbuselvam, Y and Vennila, S Heterosis studies in rice (Oryza sativa L.). Plant Archives. 1: Pandya, R and Tripathi, R.S Heterosis breeding in rice. Oryza. 43 (2):

238 *Pandey, M.P., Mani, S.C., Singh, H and Singh, J.P Genetic architecture of components of quality in rice. Paper presented at 1 st Symposium on Genetics and rice improvement organized by Central Rice Research Institute (CRRI) April, Pandey, P., Anurag, P.J., Tiwari, D.K., Yadav, S.K Genetic variability, diversity and association of quantitative traits with grain yield in rice (Oryza sativa L.). Journal of Bioscience. 17: Panse, V.G and Sukhatme, P.V Genetics and quantitative characters in relation to plant breeding. Indian Journal of Genetics. 17: Panse, V.G and Sukhatme, P.V Statistical methods for agricultural workers. Indian Council of Agricultural Research, New Delhi. Panwar, Ashvani, Sharma, R.P.S.R.K., Arya, K.P.S and Panwar, A Genetic variability and inter-relationship in rice (Oryza sativa L.). Advances in Plant Sciences. 10 (1): Panwar, L.L and Mashiat Ali, Correlation and path analysis of yield and yield components in transplanted rice. Oryza. 44 (2): Panwar, L.L Line x tester analysis of combining ability in rice (Oryza sativa L.). Indian Journal of Genetics and Plant Breeding. 65 (1): Pathak, P.K and Sharma, K.K Variability and correlation among physical quality characters of Ahu rice of Assam. Journal of the Agricultural Science Society of North East India. 9 (1): Patil, B.T Generation mean analysis in Chilli (Capsicum annuum). Vegetable Science. 38 (2): Patil, D.V, Thiyagarajan, K and Kamble, P Combining ability of parents for yield and yield contributing traits in two line hybrid rice (Oryza sativa L.). Crop Research. 25 (3): Patil, D.V., Thiyagarajan, K and Patil, P. D. 2006a. Scaling and joint scaling test for generation mean analysis in thermo sensitive genic male sterile lines of two line hybrids rice (Oryza sativa L.). Plant Archives. 6 (1): Patil, D.V., Thiyagarajan, K and Patil, P.D. 2006b. Evaluation of six parameters model of generation mean analysis in thermo sensitive genic male sterile lines of two line hybrids rice (Oryza sativa L.). Plant Archives. 6 (1):

239 Patil, P. V and Sarawgi, A.K Studies on genetic variability, correlation and path analysis in traditional aromatic rice accessions. Annals of Plant Physiology. 19 (1): Patil, P.P., Vashi, R.D., Shi Verma nde, D.A. and Lodam, V.A Nature and magnitude of heterosis for grain yield and yield attributing traits in rice (Oryza sativa L.). Plant Archives. 11 (1): Patil. P.V., Sarawgi. A.K and Shrivastava. M. N Genetic analysis of yield and quality traits in traditional aromatic accessions of rice. Journal of Maharashtra Agricultural Universities. 28 (3): Patra, B.C., Pradhan, K.C., Nayak, S.K and Patnaik, S.S.C Genetic variability in long awned rice genotypes. Environment and Ecology. 24 (1): Pawan Saini., Rose Mary Francies., Jiji Joseph., Dijee Bastian and Veena Vigneshwaran Genetic assessment of core set developed from short duration rice accessions held by Kerala Agricultural University. University Journal of Tropical Agriculture. 51 (1-2): Perera, A.M., Pooni, H.S and Saxena, K.B Components of genetic variation in short duration pigeon pea crosses under waterlogged conditions. Journal of Genetics and Breeding. 55 (1): Phillips, P.C The language interaction. Genetics. 149: Pillai, M.A and Amirthadevarathinam Inheritance of yield and its components in CMS based hybrids of cotton (Gossypium sp.). Indian Journal of Agricultural Research. 31 (3): Pradhan, S.K and Singh, S Combining ability and gene action analysis for morphological and quality traits in basmati rice. Oryza. 45 (3): Pradhan, S.K., Bose, L.K and Meher, J Studies on gene action and combining ability analysis in basmati rice. Journal of European Agriculture. 7 (2): Prasad B., Patwari A.K. and Biswas P.S Genetic Variability and selection criteria in fine grain rice. Pakistan Journal of Biological Sciences. 4 (10): Prasanthi, L Genetics of physiological attributes in rice (Oryza sativa L.). Ph. D. Thesis. Acharya N. G. Ranga Agricultural University, Hyderabad.

240 Pundhan Singh and Narayan, S.S Biometrical techniques in Plant Breeding. 4 th ed. Kalyani Publishers, New Delhi, India. Rafii, M. Y., Zakiah, M.Z., Asfaliza, R., Iffah Haifaa, M.D., Latif, M.A and Malek, M.A Grain quality performance and heritability estimation in selected F 1 rice genotypes. Sains Malaysiana. 43 (1): 1 7. Rahimi, M., Rabiei, B., Samizadeh, H and Kafi Ghasemi, A Combining Ability and Heterosis in Rice (Oryza sativa L.) Cultivars. Journal of Agricultural Science and Technology. 12: Rajendar Reddy, M., Raju, Ch. S., Sravani, D and Dayakar Reddy, T Heterosis for yield and kernel size in aromatic rice (Oryza sativa L.). Annals of Biological Research. 3 (6): Rajendar Reddy, M., Surendar Raju, Ch., Sravani, D and Narendar Reddy, S Association and path analysis betweenyield and its contributing traits in F 2 generation of aromatic rice. The Andhra Agricultural Journal. 61 (1): Rajesh Kumar Dhanwani., Sarawgi, A.K., Akash Solanki and Jitendra Kumar Tiwari Genetic variability analysis for various yield attributing and quality traits in rice (Oryza sativa L.). The Bioscan. 8 (4): Raju, Ch. S., Rao, M.V.B., Sudarshanam, A and Reddy, G.L.K Heterosis and inbreeding depression for yield and kernel characters in rice. Oryza 42 (1): Raju, Ch. S., Rao, M.V.B and Sudarshanam, A Heterosis and genetic studies on yield and associated physiological traits in rice (Oryza sativa L.). Oryza. 43 (4): Raju, Ch. S., Rao, M.V.B., Reddy, G.L.K., Rao, J.S.P and Reddy, K.S Heterosis and combining ability for some quality traits in rice (Oryza sativa L.). Annals of Agricultural Research. 24 (2): Rakesh Kumar Ddhanwani, Sarawgi, A.K., Akash Ssolanki and Jitendra Kumar Tiwari Genetic variability analysis for various yield attributing and quality traits in rice (Oryza sativa L.). The Bioscan. 8 (4): Ram, T Heterosis and inbreeding depression in rice. International Rice Research News Letter. 17 (5&7).

241 Ram, T Genetics of yield and its components in rice (Oryza sativa L.). Indian Journal of Genetics. 54 (21): Ram, T., Singh, J and Singh, R.M Combining ability for yield and its components in rice. Oryza. 35 (3): Ramakrishna, S., Mallikarjuna Swamy., Mishra, B., Virakthamath, B. C and Ahmed M. Illyas Characterization of thermo-sensitive genetic male sterile lines for temperature sensitivity, morphology and floral biology in rice (Oryza sativa L.). Asian Journal of Plant Sciences. 5: Ramalingam, J., Nadarajan, N., Vanniarajan, C and Rangasamy, P Combining ability studies involving CMS lines in rice. Oryza 34: 4-7 Ramalingam, J., P. Vivekanandan and M. Subramanian Combining ability in rice. Oryza, 30: Ramesh Babu, P Genetic analysis of yield and grain quality attributes in Rice (Oryza sativa L.). Ph. D Thesis. Acharya N.G. Ranga Agricultural University, Hyderabad, India. Ramesh Kumar, V.V Genetic analysis of yield and its components in four rice crosses. Journal of Research APAU. 17 (1): 11. Rameshkumar and Thakral, N.K.2003a. Inheritance of plant height, branches and seed yield per plant in Indian mustard. National Journal of Plant Improvement. 5 (2): Rameshkumar and Thakral, N.K. 2003b. Genetic architecture of length of main spike and siliqua on main raceme in Indian mustard. Haryana Agricultural University Journal of Research. 33 (2): Ranganathan, T.B., Rangasamy, S.R.S and Menon, P.M Genetic investigation on duration of flowering and yield in semi-dwarf varieties of rice. International Rice Common Newsletter. 22 (4): Rao, S.S and Shrivastav, M.N Genetic variation and correlation studies in rainfed upland rice. Oryza. 31: Rao, S.S and Shrivastav, M.N Association among yield attributes in upland rice. Oryza. 36 (1):

242 Rather, A.G., Mir, G. N and Sheikh, F.A Genetic parameters for some quantitative traits in rice. Advances in Plant Sciences. 19 (2): Ravindra Babu, V., Shreya, K., Kuldeep Singh Dangi, G., Usharani, P and Nagesh Genetic variability studies for qualitative and quantitative traits in popular rice (Oryza sativa L.) hybrids of India. International Journal of Scientific and Research Publications. 2 (6): 1-5. Ravindra Babu, V., Shreya, K., Kuldeep Singh Dangi., Usharani, G and Siva Shankar, A Correlation and path analysis studies in popular rice hybrids of India. International Journal of Scientific and Research Publications. 2 (3): 1-5. Ravindranadh, B., Peraiah, A., Sreerama Reddy, N., Subramanyam, D., Ramayya, B and Murthy, K.R.K Interrelationships between yield and yield components in rice. The Andhra Agricultural Journal. 29 (4): Reddy, C.D.R and Nerkar, Y.S Heterosis in F 1, inbreeding depression and heritability estimates in F 2 of rice crosses. Crop Research. 4 (2): Reddy, C.D.R and Nerkar, Y.S Heterosis and inbreeding depression in upland rice crosses. Indian Journal of Genetics and Plant Breeding. 55 (4): Reddy, C.D.R., Nerkar, Y.S and Dhanalakhmi, G Heterosis and inbreeding depression for grain size and yield in rice (Oryza sativa L.) under direct seeding. Indian Journal of Agricultural Sciences. 61 (6): Reddy, J.N and De, R.N Genetic variability in low land rice. Madras Agricultural Journal. 83 (4): Reddy, J.N Heterosis and inbreeding depression in short duration rice. Madras Agricultural Journal. 83 (6): Reddy, J.N Combining ability for grain yield and its components in lowland rice. Indian Journal of Genetics and Plant Breeding. 62 (3): Reddy, J.N., De, R.N and Suriya Rao, A.V Correlation and path analysis in low land rice under intermediate (0-50 cm) water depth. Oryza. 34 (3): Regina, A., Bai, N.R., Devika, R and Joseph, C.A Genetic variability and correlation in short duration rice cultivars. Journal of Tropical Agriculture. 32 (2):

243 Remabai, N., Ahmed Regina Devika, R and Joseph, C.A Genetic variability and association of characters in medium duration rice genotypes. Oryza. 29: Robin, S Genetic analysis of yield, yield components and physiological attributes related with drought tolerance in rice (Oryza sativa L). Ph.D. Thesis. Tamil Nadu Agricultural University, Coimbatore. Rogbell, J.E and Subbaraman Line x tester analysis for combining ability in saline rice cultivars. Madras Agricultural Journal. 84 (1): Rosamma, C. A and Vijayakumar, N. K Variation in quantitative characters and heterosis in F 1 rice (Oryza sativa L.) hybrids as affected by male sterile cytoplasm. Indian Journal of Genetics and Plant Breeding. 67 (1): Roy, A and Panwar, D.V.S Nature of gene interaction in rice. Annals of Agricultural Research. 14 (3): Roy, A., Panwar, D.V.S and Sarma, R.N Genetic variability and causal relationships in rice. Madras Agricultural Journal. 82 (4): Roy, B and Mandal, A.B Combining ability of some quantitative traits in rice. Indian Journal of Genetics and Plant Breeding. 61 (2): Roy, S. K and Senapati, B.K Combining ability analysis for grain yield and quality characters in rice (Oryza sativa L). Indian Journal of Agricultural Sciences. 82 (4): Roy, S.K., Senapati, B.K., Sinhamahapatra, S. P and Sarkar, K.K. (2009). Heterosis for yield and quality traits in rice. Oryza. 46: Sadhukhan, R.N and Chattopadhyay, P Variability and character association between yield attributes and grain quality in aromatic rice. Journal of Interacadamicia. 4 (4): Sahai, V.N., Mandal, R.K., Chatterjee, S.K and Chaudhary, R.C Heterosis of grain Quality characters in some hybrid rice. Oryza. 23: Sahdev Singh, Dhaka, R.P.S and Malik, S.S Heritability and genetic advance in irradiated population of rice. Crop Research. 11 (2): Saidaiah, P., Sudheer kumar, S and Ramesha, M.S Combining ability studies for development of new hybrids in rice over environments. Journal of Agricultural Science. 2 (2):

244 Sakthivel, P Genetic divergence and genetic analysis of yield attributes and certain quality traits in rice (Oryza sativa L). M.Sc. (Ag) Thesis. Acharya N.G. Ranga Agricultural University, Hyderabad. Salgotra, R. K., Gupta, B. B. and Singh, P Combining ability studies for yield and yield components in Basmati rice. Oryza. 46 (1): Samadia, D. K Genetic variability studies in Lasora (Cordia myxa Roxb.). Indian Journal of Plant Genetic Resources. 18 (3): Sameerkumar, C.V Genetics of resistance to Fusarium wilt and yield contributing characters in pigeon pea (Cajanus cajan L.). Ph.D. Thesis. Acharya N.G. Ranga Agricultural University, Hyderabad. Sangam Kumar Singh., Chandra Mohan Singh and. Lal, G.M Assessment of genetic variability for yield and its component characters in rice. Research in Plant Biology. 1(4): Sanjeev Kumar, Singh, H.B., Sharma, J.K and Salej Sood Heterosis for morphophysiologocal and qualitative traits in rice (Oryza sativa L.). Oryza. 47 (1): Sanjeev Kumar., Singh, H.B and Sharma, J.K. 2007a. Combining ability analysis for grain yield and other associated traits in rice. Oryza. 44 (2): Sanjeev Kumar., Singh, H.B and Sharma, J.K. 2007b. Inbreeding depression for grain yield, yield attributes and quality characteristic in rice (Oryza sativa L.). Oryza. 44 (1): Sankar, P.D., Sheeba, A and Anbumalarmathi, J Variability and character association studies in rice (Oryza sativa L.). Agricultural Science Digest. 26 (3): Sao, A., Studies on combining ability and heterosis in F 1 rice hybrids using cytoplasmic male sterile lines. M. Sc. (Ag.) Thesis. Indira Gandhi Agricultural University, Raipur. Sarangi, D.N., Pradhan, B. Sial, P and Mishra, C.H.P Genetic variability, correlation and path-coefficient analysis in early rice genotypes. Environment and Ecology. 27:

245 Sarathe, M.L., Singha, S.P and Perraju, P Heterosis and combining ability for quality characters in rice. Indian Journal of Agricultural Sciences. 56 (11): Saravanan, R and Senthil, N Genotypic and phenotypic variability, heritability and genetic advance in some important traits in rice. Madras Agricultural Journal. 84 (5): Saravanan, K., Anbanandan, V and Sateesh kumar, P Heterosis for yield and yield components in rice (Oryza sativa L.). Crop Research. 31(2): Saravanan. K., Ramya. B., Santhosh Kumar, P and Sabesan, T Combining ability for yield and quality characters in rice (Oryza sativa L.). Oryza. 43 (4): Sarawgi, A.K., Rastogi, N.K and Soni, D.K Studies on some quality parameters of indigenous rice in Madhya Pradesh. Annals of Agricultural Research. 21 (2): Sardhana, S and Borthakur, D.N Combining ability for yield in rice. Oryza. 24: Sarial Ashok, K., Savial Sindhu, S and Singh, N.P Combining ability of new basmati fertility restorers for grain yield and its components in rice (Oryza sativa L.). Indian Journal of Genetics and Plant Breeding. 67 (2): Sarial, A.K., Singh, V.P and Khusi Ram Heterotic potential of basmati fertility restorers for grain yield and its components in rice (Oryza sativa L.). Indian Journal of Genetics and Plant Breeding. 66: Sarkar, K. K., Bhutia, K. S., Senapati, B. K., Roy, S. K., Panda, S. and Mondal, A. B Genetic variability and relationship between grain yield and its component traits in Rice (Oryza sativa). Journal of Environment and Ecology. 23: Sarker, S.K., Ray, B.P., Sarker, M and Saha, S Genetic variability, correlation and path coefficient analysis in aman rice (Oryza sativa L.). Journal of Biological and Chemical Research. 30 (2): Sarma, M.K., Sharma, A.K., Agrawal, R.K and Richharia, A.K Combining ability and gene action for yield and quality traits in Ahu rice of Assam. Indian Journal of Genetics and Plant Breeding. 67 (3): Sarma, R.N and Roy, A Studies on variability and inter-relationship of yield attributes in jhum rice. Annals of Agricultural Research. 14 (3):

246 Sarwar, A.K.M.G., Ali, M.A and Prodhan, A.K.M.A Variability in grain morphology of some cultivated rice in Bangladesh. Indian Journal of Agricultural Research. 33 (1): Satheesh kumar, P and Saravanan, K Studies on heterosis over better parent and standard parent for yield traits in rice (Oryza sativa L.). Plant Archives. 11 (2): Satheesh kumar, P., Saravanan, K and Sabesan, T Combining ability for yield and yield contributing characters in rice (Oryza sativa L.). Electronic Journal of Plant Breeding. 1 (5): Sathya, A., Kandasamy, G and Ramalingam, J Heterosis in hybrid rice. Crop Research. 18 (2): Satish Chandra, B., Dayakar Reddy, T., Ansari, N.A and Sudheer Kumar, S Correlation and path analysis for yield components in rice (Oryza sativa L.). Agricultural Science Digest. 29 (1): Satish, Y., Seetha Ramaiah, K.V., Srinivasulu, R and Sree Rami Reddi, N Correlation and path analysis of certain quantitative and physiological characters in rice (Oryza sativa L.). The Andhra Agricultural Journal. 50 (3&4): Satya Priya Lalitha, V and Sreedhar, N Estimates of genetic parameters for quality traits in rice. Annals of Agricultural Research. 20 (1): Satyanarayana, P.V., Reddy, M.S.S., Ish Kumar and Madhuri, J Combining ability studies on yield and yield components in rice. Oryza. 37 (1): Selvarani, M and Rangasamy, P Correlation and Path analysis in Rice. Madras Agricultural Journal. 85 (1): Selvi, B., Rangasamy, P., Nadarajan, N Combining ability analysis for physiological traits in rice. Oryza. 38 (1&2): Senapati, B. K., Pal, S., Roy, S., De, D.K. and Pal, S. Selection criteria for high yield in early segregating generation of rice (Oryza sativa L.) crosses. Journal of Crop and Weed. 5 (2): Seyoum, M., Alamerew, S and Bantte, K Genetic variability, heritability, correlation coefficient and path analysis for yield and yield related traits in upland rice. Journal of Plant Sciences. 7 (1):

247 Shanthala, J., Latha, J and Hittalmani, S Heterosis of rice (Oryza sativa L.) hybrids for growth and yield components. Research on Crops. 7(1): Shanthi, P., Jebaraj, S and Geetha, S Correlation and path coefficient analysis of some sodic tolerant physiological traits and yield in rice (Oryza sativa L.). Indian Journal of Agricultural Research. 45 (3): Shanthi, P., Shanmugasundaram, P and Nagarajan, P Combining ability analysis in rice. Oryza. 40 (1&2): Shanthi, P., Shanmugasundaram, P., Jebaraj, S and Nagarajan, P Combining ability analysis in three line rice hybrids. Madras Agriculture Journal. 91 (7-12): Sharifi, P., Dehghani, H., Mumeni, A and Moghaddam, M Genetic and Genotype Environment interaction effects for appearance quality of rice. Agricultural Sciences in China. 8 (8): Sharma, A.K and Sharma, R.N Genetic variability and character association in early maturing rice. Oryza. 44 (4): Sharma, R.K and Mani, S.C Combining ability analysis for physical grain quality in basmati rice. Oryza. 35 (3): Sharma, R.K and Mani, S.C Analysis of gene action and combining ability for yield and its component characters in rice. Oryza. 45 (2): Sharma, S.K., Singh, S.K., Nandan, R., Amita Sharma., Ravindra Kumar., Kumar, V and Singh, M.K Estimation of heterosis and inbreeding depression for yield and yield related traits in rice (Oryza sativa L.). Molecular Plant Breeding. 4 (29): Shivani, D and Sree rama reddy, N Variability, heritability and genetic advance for morphological and physiological traits in certain rice hybrids. Oryza. 37 (3): Shivani, D., Viraktamath, B.C., Shobha Rani, N. 2009a. Combining ability for yield and grain quality characters in indica/indica hybrids of rice. Oryza. 46 (2): Shivani, D., Viraktamath, B.C and Shobha Rani. 2009b. Heterosis for quality traits in indica/indica hybrids of rice. Oryza. 46 (3):

248 Shukla, S.K and Pandey, M.P Combining ability and heterosis over environments for yield and yield components in two line hybrids involving thermo sensitive genic male sterile lines in rice (Oryza sativa L.). Plant Breeding. 127 (1): Singh S.K., Singh, C.M. and Lal, G.M Assessment of genetic variability for yield and its component characters in rice (Oryza sativa L.). Research in Plant Biology. 1 (4): Singh, N.K., Singh, P.K., Singh, O.N., Singh, S., Dwivedi, J.L., Giri, S.P and Tiwari, T Gene effects and selection parameters in rainfed low land rice. Oryza. 44 (4): Singh, N.B and Singh, H.G Heterosis and combining ability for kernel size in rice. Indian Journal of Genetics. 45 (2): Singh, N.K., Singh, S., Singh, A.K., Sharma, C.L,, Singh, P.K and Singh, O.N Study of heterosis in rice (Oryza sativa L.) using line x tester mating system. Oryza. 44 (3): Singh, R.K and Chaudhary, B.D Biometrical methods in quantitative genetic analysis. Kalyani Publishers, New Delhi, India. Singh, R.K and Lal, J.P Exploitation of heterosis in aromatic rices for different physico-chemical traits. Indian Journal of Genetics and plant Breeding. 65 (1): Singh, R.K., Singh, U.S and Khush, G.S Aromatic Rices. IRRI, Manila, Philippines. pp 46. Singh, R.V., Verma, O.P., Dwivedi, J.L and Singh, R.K. 2006b. Heterosis studies in rice hybrids using CMS systems. Oryza. 43 (2): Singh, RK., Singh Omkar and Prasad, B.K. 2006a. Heterosis in long grain aromatic rice for yield and quality components. Annals of Agricultural Research. 27 (2): Singh, S.B., Srivastava, R.K., Giri, S.P and Yadav, L.S Heritability, genetic advance and correlation studies in indigenous rice (Oryza sativa L) cultivars of Uttar Pradesh. Journal of Living World. 5 (1): Singh, S and Chaudhary, B.S Variability, heritability and genetic advance in cultivars of rice (Oryza sativa L.). Crop Research. 12 (2):

249 Singh, S.K and Haque, M.F Heterosis for yield and yield components in rice (Oryza sativa L.). Indian Journal of Genetics and Plant Breeding. 59 (2): Sinha, P.K., Prasad, C and Prasad, K Studies on Gora rice of Bihar III Association of panicle components and grain characters. Oryza. 36 (4): Sinha, S.K., Tripathi, A.K, and Bisen, U.K Study of genetic variability and correlation coefficient analysis in midland land races of rice. Annals of Agricultural Research. 25 (1): 1-3. Siva Subramanian, S and Madhavamenon, P Combining ability in rice. Madras Agricultural Journal. 60: Snedecor, G.W and Cochran, W.G Statistical methods. 6 th edition Iowa State University Press, Ames Iowa. *Sprague, G.F and Tatum, L.A General Vs. specific combining ability in single crosses of corn. Journal of American Society of Agronomy. 3: Sreedhar, M Genetic analysis of grain quality characters in non - scented rice. Ph. D. Thesis. Acharya N. G. Ranga Agricultural University, Hyderabad. Srivastava, A.K., Jaiswal, H.K., Agarwal, R.K and Singh, R.P Genetic architecture of yield and yield components in indigenous aromatic rice (Oryza sativa L.). Vegetos. 25 (1): Srivastava, M.K and Shukla, R.S Genetic variability in segregating (F 2 ) populations under different levels of fertility in rice. Advances in Agriculture Research in India. 6: Sudharani, M., Raghava Reddy, P., Ravindra Babu, V and Hariprasad Reddy, G Correlation and path coefficient analysis for yield and physiological attributes in rice (Oryza sativa L.) under saline soil conditions. The Andhra Agricultural Journal. 61 (1): Sukanya Subramanian and Rathinam, M Genetic components of variation in rice. Madras Agricultural Journal. 71: Suman, A Studies on genetic diversity and agro-morphological characterization of rice (Oryza sativa L.) germplasm. M.Sc. (Ag.) Thesis. Acharya N.G. Ranga Agricultural University, Hyderabad.

250 Suman. A., Gouri Shankar, V., Subbarao, L.V and Sreedhar, N Variability, heritability and genetic advance in rice (Oryza sativa L.). Crop Research. 30 (2): Supriyo Chakraborty and Hazarika, M.K Estimation of various genetic parameters for yield and yield components in rice. Oryza. 31: Supriyo Chakraborty., Pradip, K. Das., Biswajit Guha., Kalyan K. Sarmah and Bhubaneswar Barman Quantitative genetic analysis for yield and yield components in boro rice (Oryza sativa L.). Notulae Scientia Biologicae. 2 (1): Surender Raju, Ch Study of genetic divergence, variability, stability, gene action and character association for certain physiological quality and yield components in Rice (Oryza sativa L.) Ph. D. Thesis. Acharya N.G. Ranga Agricultural University, Hyderabad. Suryanarayana, Y Genetic studies on drought tolerance in Rice (Oryza sativa L.) Ph. D. Thesis. Acharya N. G. Ranga Agricultural University, Hyderabad. Swain, B and Reddy, J.N Correlation and path analysis of yield and its components in rainfed lowland rice genotypes under normal and delayed planting conditions. Oryza. 43 (1): Swain, B., Acharya, B and Pandey, K Combining ability analysis for yield and yield components in low land rice. Oryza. 40 (3&4): Tara Satyavathi, C., Bharadwaj, C.H and Subramanyam, D Variability, correlation and path analysis in rice varieties under different spacings. Indian Journal of Agricultural Research. 35 (2): Thakur, S.K, Choubey, S.K and Sharma, N.P Genetic variability and character association in F 2 population in rice (Oryza sativa L.). Journal of Soils and Crops. 8 (2): Thakur, S.K., Choubey, S.K and Sharma, N.P Genetic variability and character association in F 2 (Anupama x IR 36) population in rice (Oryza sativa L.). Agricultural Science Digest. 19 (3): Thirugnana kumar, S., Narasimman, R., Senthil kumar, N., Eswaran, R and Praveen Sampath kumar, C Gene effects for grain yield and its component characters in rice (Oryza sativa L.). Crop Improvement. 34 (1):

251 Thirugnanakumar, S., Narasimman, R., Anandan, A and Senthil Kumar, N Studies of genetics of yield and yield component characters in F 2 and F 3 generations of rice (Oryza sativa L.). African Journal of Biotechnology. 10 (41): Thirumala Rao, V., Chandra Mohan, Y., Bhadru, D., Bharathi, D and Venkanna, V Genetic variability and association analysis in rice. International Journal of Applied Biology and Pharmaceutical Technology. 5 (2): Tiwari, D.R., Pandey, P., Giri, S.P., and Dwivedi, J.L Heterosis studies for yield and its components in rice hybrids using CMS system. Asian Journal of Plant Sciences. 10 (1): Tiwari, V.N and Sarathe, M.L Heterosis and inbreeding depression in direct seeded rainfed rice. Oryza. 37 (2): Tomar, J.B Analysis of genetic components of generation mean for some quality characters in rice. Oryza. 24: Tripathi, A.K., Sinha, S.K and Bhandarkar, S Studies on variability, heritability and genetic advance of semi deep water rice. Advance in Plant Sciences. 12 (1): 235. Tyagi, J.P., Tejbir Singh and Singh, V.P Genetic analysis of combining ability for quality characters in Basmati rice. Oryza. 47 (2): Ullah, M.Z., Bashar, M.K., Bhuiyan, M.S.R., Khalequzzaman, M. and Hasan, M.J Inter relationship and cause-effect analysis among morpho-physiological traits in biroin rice of Bangladesh. International Journal of Plant Breeding and Genetics. 5 (3): Umadevi, M., Veerabadhiran, P., Manonmani, S and Shanmugasundaram, P Physico-chemical and cooking characteristics of rice genotypes. Electronic Journal of Plant Breeding. 1 (2): Unay, A and Turgut, I Genetic analysis of earliness characters at first picking in upland cotton. Turkish Journal of Field Crops. 1 (2): Vaithilingam, R Genetics analysis of earliness and yield components in rice (Oryza sativa L.). Ph. D. Thesis. Tamil Nadu Agricultural University, Coimbatore.

252 Vaithiyalingan, M and Nadarajan, N Genetic variability, heritability and genetic advance in F 2 population of inter sub-specific crosses of rice. Crop Research. 31 (3): Valarmathi, G and Leenakumari, S Character association analysis in rice varieties under upland conditions. Madras Agricultural Journal. 85 (10-12): Vanaja, T and Babu, L.C Heterosis for yield and yield components in rice (Oryza sativa L.). Journal of Tropical Agriculture. 42 (1-2): Vanaja, T., Babu, L.C., Radhakrishnan, V.V. and Pushkaran,K Combining ability for yield and yield components in rice varieties of diverse origin. Journal of Tropical Agriculture. 41: Vange, T and Ojo, A.A Variability and heritability estimates of yield and yield components in some Nigerian low land rice genotypes. International Rice Research Newsletter. 6. Vange, T Biometrical studies on genetic diversity of some upland rice (Oryza sativa L.) accessions. Nature and Science. 7 (1): Vange, T., Ojo, A.A and Bellow, L.L Genetic variability, stability and correlation studies in lowland rice (Oryza sativa L.) genotypes. Indian Journal of Agricultural Sciences. 69 (1): Vanisree, S., Raju, Ch. S., Reddy, P.N., Sreedhar, M and Krishna, L Heterosis and gene effects for grain yield and physiological traits in rice (Oryza sativa l.). Journal of Research ANGRAU. 39 (4): 1-5. Vanisree, S., Swapna, K., Damodar Raju, Ch., Surender Raju, Ch and Sreedhar, M Genetic variability and selection criteria in rice. Journal of Biological and Scientific Opinin. 1 (40): Vanniarajan, C., Rangasamy, P., Ramalingam, J., Nadarajan, N and Arumugampillai Studies on genetic variability in hybrid rice derivatives. Crop Research. 12 (1): *Ved Narain., Singh, P.K., Kumar, N and Singh, V.S Gene effects for grain yield and related traits in sorghum (Sorghum bicolor L.). Indian Journal of Genetics. 67 (1):

253 Venkanna, V., Rao, M.V.B, Raju, CH.S., Rao, V.T and Lingaiah. N Association analysis of F 2 generation in rice (Oryza sativa L.). International Journal of Pure Applied Bioscience. 2 (2): Venkata Subbaiah, P., Reddi Sekhar, M., Reddy, K. H. P and Eswara Reddy, N.P Variability and genetic parameters for grain yield and its components and kernel quality attributes in CMS based rice hybrids (Oryza sativa L.). International Journal of Applied Biology and Pharmaceutical Technology. 2 (3): Venkata Suresh, A Genetic analysis for certain quantitative and qualitative traits in F 2 populations of rice (Oryza sativa L.). M.Sc. (Ag) Thesis. Acharya N.G. Ranga Agricultural University, Hyderabad. Venkatesan, M., Anbuselvam, Y., Elangaimannan, R and Karthikeyan, P Combining ability for yield and physical characters in rice. Crop Improvement. 44 (4): Verghese, E.J A standard process for cooking of rice for experimental purpose. Madras Agricultural Journal. 37: Verma O P, Santhoshi U S and Srivastava H K 2002 Heterosis and inbreeding depression in half diallel crosses involving diverse ecotypes of rice. Journal of Genetics and Plant Breeding. 56: Verma, R.S., Yadav, R.D.S and Giri, S.P Genetics of yield and its important components in rice (Oryza sativa L.). Crop Research. 31 (1): Verma, R.S., Yadav, R.D.S., Singh, R.S., Giri, S.P and Dwivedi, J.L Studies on heterosis and inbreeding depression in rice (Oryza sativa L.). Oryza. 41 (3&4): Vijaya lakshmi, B., Vinay kumar, M., Srinivas, B and Seetharamaiah, K.V Line x tester analysis of combining ability studies in rice (Oryza sativa L.). Research on Crops. 9 (3): Vijayakumar, S.B., Kulkarni, R.S and Murthy, N Line x tester analysis for combining ability in ratooned F 1 rice. Oryza. 31: Vinothini, S and Ananda Kumar, C.R Correlation Path Coefficient Analysis in Drought Tolerant Rice cultures for yield. The Andhra Agriculture Journal. 52 (3&4):

254 Virmani. S.S Heterosis and hybrid rice breeding. Monograph on Theoretical and Applied Genetics. Vol. 22. Springer-Verlag, Berlin Heidelberg. Vishwakarma, D.N., Maurya, D.M., Mishra, S.K., Verma, G.P and Rakesh Kumar Heterosis studies in rice using CMS system. Annals of Agricultural Research. 19 (4): Vivek, S., Singh, S., Singh, S.K. and Singh, H Estimation of genetic variability, heritability and genetic advance in rice (Oryza sativa L.). Agriculture Science Digest. 25 (3): Vivekanandan, P and Giridharan, S Inheritance of aroma and breadth wise grain expansion in basmati and non-basmati rices. International Rice Research Notes. 19 (2): 4-5. Vivekanandan, P and Giridharan, S Genetic analysis of kernel quality traits in rice. Oryza. 32: Vivekanandan, P and Giridharan, S Genetic variability and character association for kernel and cooking quality traits in rice. Oryza. 35 (3): Wilfred Manuel, W and Prasad, M.N Combining ability and heterosis in rice (Oryza sativa L.). Oryza. 29: *Wright, S Correlation and causation. Journal of Agricultural Research. 20: Yadav, H.N., Agarwal, R.K and Singh, S.P Inheritance of qualitative and quantitative traits in rice (Oryza sativa L.) employing partial diallel analysis over years. Crop Improvement. 34 (2): Yadav, L.S., Maurya, D.M., Giri, S.P and Singh, S.B Nature and magnitude of heterosis for growth, yield and yield components in hybrid rice. Oryza. 41 (1&2): 1-3. Yadav, S.K., Suresh, B.G., Praveen Pandey and Binod Kumar Assessment of genetic variability, correlation and path association in rice (Oryza sativa L.). Journal of Biosciences. 18: 1-8. Yadhav, Y.P., Raviprakash., Ranvirsingh., Singh, R.K and Yadava, J.S Genetics of yield and its components characters in Indian mustard (Brassica juncea L.) under rainfed conditions. Journal of Oilseeds Research. 22 (2):

255 Yadav, S.K., Pandey. P., Kumar, K and Suresh, B.G Genetic architecture, inter relationship and selection criteria for yield improvement in rice (Oryza sativa L.). Pakistan Journal of Biological Sciences. 14: Yogameenakshi, P., Nadarajan, N and Anbumalarmathi, J Correlation and path analysis on yield and drought tolerant attributes in rice (Oryza sativa L.) under drought stress. Oryza. 41 (3&4): Yolanda and Vijendradas, L.D Study on heterosis in hybrid rice. Oryza. 32 (2): Yugandhar Reddy, M., Subhash Chandra Yadav., Suresh Reddy, B., Lavanya, G.R and Suresh Babu, G Character association and component analysis in rice. Oryza. 45(3): Yussouf Saleem, Md., Javed Iqbal Mirza and Ahsanul haq, Md Combining ability analysis of some morphophysiological traits in basmati rice. Pakistan Journal of Botany. 42 (5): * Original not seen. The pattern of Literature Cited presented above is in accordance with the Thesis Format Guidelines, 2010 for thesis presentation for Acharya N. G. Ranga Agricultural University, Hyderabad, India.

256 Plate 3.1. Evaluation of parents, F 1 s and F 2 s at Agriculture Research Station, Kampasagar, Nalgonda district (Telangana)

257 Plate 4.1. Best specific and heterotic cross for yield characters (panicle length, panicle weight, number of filled grains/panicle and 1000 grain weight and grain yield)

258 Plate 4.2. Best specific and heterotic cross for yield characters (number of productive tillers/plant, panicle weight, number of filled grains/panicle and grain yield)

259 Plate 4.3. Best specific and heterotic cross for yield and quality characters (panicle length, number of filled grains/panicle, 1000 grain weight, kernel length, kernel breadth, kernel L/B ratio and grain yield)

260 Plate 4.4. Top ranking crosses with heterosis and specific combining ability for kernel length

261 Plate 4.5. Top ranking crosses with heterosis and specific combining ability for kernel breadth

262 Plate 4.6. Top ranking crosses with heterosis and specific combining ability for kernel L/B ratio

263 Plate 4.7. Top ranking crosses with heterosis and specific combining ability for kernel length after cooking

264 Plate 4.8. Top ranking crosses with heterosis and specific combining ability for kernel elongation ratio

265 Plate 4.9. Top ranking crosses with heterosis and specific combining ability for head rice recovery