HETEROTIC EFFECTS FOR YIELD AND PROTEIN CONTENT IN WHITE QUALITY PROTEIN MAIZE

Transcription

1 Sarhad J. Agric. Vol.27, No.3, 2011 HETEROTIC EFFECTS FOR YIELD AND PROTEIN CONTENT IN WHITE QUALITY PROTEIN MAIZE IKRAMULLAH,* IFTIKHAR HUSSAIN KHALIL*, MUHAMMAD NOOR* and MOHAMMAD KAUSAR NAWAZ SHAH** * Department of Plant Breeding & Genetics, Agricultural University, Peshawar Pakistan. ** Department of Plant Breeding & Genetics, Arid Agriculture University, Rawalpindi Pakistan. ABSTRACT The present study was performed to determine the magnitude of genetic variability and to identify heterotic populations for maturity, yield, and grain protein content. High genetic variability among the inbred lines and resultant F 1 hybrid populations was observed for all traits as indicated by high level of heterosis over the mid and high parent. For this purpose, four S 5 quality protein maize inbred lines (NC1QW1, NC1QW3, NC1QW5 and NC1QW13) were crossed in diallel fashion during The four inbred lines and twelve crosses were evaluated at two locations; Agricultural University, Peshawar () and Cereal crops Research Institute (), Pirsabak, Nowshera, Khyber Pakhtunkhwa Province, Pakistan during Randomized complete block design with three replications was used at each location. Grain yield of white QPM lines and their resultant F 1 hybrids was generally higher at than. However, mid and best-parent heterotic effects for grain yield were greater in magnitude at than. Grain yield of parental lines ranged from 1951 to 3934 kg ha -1 at vs to 4435 kg ha -1 at. Similarly, grain yield of white QPM F 1 hybrids ranged from 4214 to 5758 and 5093 to 6597 kg ha -1 at and, respectively. Among F 1 hybrids, NC1QW5 NC1QW13 was the high yielding at (5758 kg ha - 1 ), while its reciprocal cross (NC1QW13 NC1QW5) ranked first for grain yield at (6908 kg ha -1 ). For protein content, F 1 hybrid NC1QW5 NC1QW3 at displayed highest values of mid-parent (8.72%) and best-parent (7.48%) heterosis. On the basis of F 1 yield and protein content, NC1QW3, NC1QW5, NC1QW13 and their F 1 hybrid populations are suggested for further exploitation in maize breeding programmes for varied purposes. Key Words: Quality protein maize, diallel, f 1 hybrids, mid- and best-parent heterosis. Citation: Ikramullah, I.H. Khalil, M. Noor and M.K.N. Shah Heterotic effects for yield and protein content in white quality protein maize. Sarhad J. Agric. 27 (3): INTRODUCTION Maize (Zea mays L.) is the leading world cereal in terms of both total production (720 million tons) and yield (FAO, 2009). Being a C4 plant, maize is capable of utilizing solar radiation more efficiently compared to other cereals. Despite high genetic potential and photosynthetic explorative crop, its average productivity in the world is 4906 kg ha -1. There is no cereal on earth that has so immense yield potential as maize and that is why it is termed as Queen of Cereals. Globally, maize contributes 15% of the protein and 20% of the calories derived from food crops in the world s diet (National Research Council, 1988). In many developing countries of Latin America, Africa and Asia, maize is the staple food and sometimes the only source of protein in diet, especially in weaning food for babies. With its high content of carbohydrates, fats, proteins, some of the important vitamins and minerals, maize has acquired a well-deserved reputation as a poor man s nutricerea. Several million people, particularly in developing countries, derive their protein and calorie requirements from maize where animal protein is scarce and expensive and consequently unavailable to a vast sector of the population. Normal maize, being deficient in amino acids such as lysine, tryptophane, and threonin that are essential for monogastric animals and humans, is nutritionally poor with biological value (amount of nitrogen that is retained in the body) of 40 to 57% (Bressani, 1992). Cereal proteins contain on average about 2% lysine, which is less than one-half of the concentration recommended for human nutrition by the Food and Agriculture Organization of the United Nations (FAO, 2009). This nutritional deficiency is of concern, particularly for people with high protein requirements, e.g., young children, pregnant or lactating women and the ill, in countries where maize is a staple food and often a significant source of protein. Quality protein maize (QPM) with homozygous embryo and endosperm for mutant alleles O 2 at the á-zeins regulatory gene opaque-2 shows about 60 to 100% increase in lysine and tryptophan. Because of the increase in concentration of these two essential amino acids, increased digestibility and increased nitrogen uptake relative to normal-endosperm maize, the biological value of QPM is about 80%, whereas that of normal maize is 40 to 57% (Bressani, 1992). QPM has about 90% of the biological value of cow milk (National Research Council, 1988). An alternative use of QPM is in feed rations for livestock, poultry or fish, where conventional sources of lysine,

2 Ikramullah et al. Hetrerotic effect for yield and protein content in white quality maize 404 generally soybean meal or synthetic lysine, raise feed and consequently production cost (Knabe et al., 1992; Pereira, 1992). The currently available QPM is the result of two decades of breeding work to overcome low yield and various other agronomic deficiencies, and the opaque endosperm phenotype associated with the original opaque-2 maize (Bjarnason and Vasal, 1992). Scientists at CIMMYT have used back cross and recurrent selection techniques to convert several maize populations to opaque-2 and subsequently modify the undesirable traits associated with the mutations (Bjarnason and Vasal, 1992; Villegas et al., 1992). Heterosis is important in maize breeding and is dependent on level of dominance and diversity in gene frequencies. The manifestation of heterosis depends on genetic divergence of two parental varieties (Hallauer and Miranda, 1988). Heterosis is the phenomenon wherein the performance of an F l derived by crossing two genetically different individuals is superior to that of the mean of the parents or the better parent. Maize has great potential for heterotic manifestation and its exploitation. This could be the reason that number of hybrid varieties in maize is much higher than any other varietal types i.e. open pollinated, double cross, synthetics or three way crosses. The objective of this study was to estimate heterotic effects for maturity, yield and grain protein content in the S 5 derived F 1 hybrids using 4 4 diallel mating in white QPM. MATERIALS AND METHODS Four S 4 QPM inbred lines (NC1QW1, NC1QW3, NC1QW5 and NC1QW13) obtained from the National Agricultural Research Centre (NARC), Islamabad, Pakistan were used as genetic material in this study. During 2006, approximately good looking plants in each S 4 line were selected and self to produce S 5 lines. The four white S 5 QPM lines were crossed in all possible combinations in spring 2007 to produce S 5 F 1 single cross hybrids. The twelve S 5 F 1 cross hybrids developed along with the four S 5 inbred lines were evaluated at two locations of Khyber Pakhtunkhwa Province viz. Agricultural University Peshawar and Cereal Crops Research Institute (), Pirsabak, Nowshera, Pakistan in summer Randomized complete block design with three replications was used at each location. Each parental line and hybrid was planted in 5m long two row plots, each 0.75m apart with plantto-plant distance of 0.25 m. Standard cultural practices were applied throughout the crop season. Data were recorded on days to tasseling and silking, biological yield, grain yield and grain protein content. The chemical analysis for grain protein content was performed at the Institute of Biotechnology and Genetic Engineering (IBGE), Khyber Pakhtunkhwa Agricultural University, Peshawar. The data were analyzed across the two locations to determine the magnitude of genotype location interaction. The following heterotic effects were also computed using Microsoft excel (Fehr, 1987). (i) Mid-parent Heterosis (%) = ((F 1 - MP)/MP) 100 (ii) Best-parent Hetrosis (%) = ((F 1 - BP)/BP) 100 Where F 1 = Mean of F 1 hybrid for a specific trait MP = Mean of the two parents in a cross for a specific trait BP = Mean of the best parent in a cross for a specific trait Significance of the mid-parent and best-parent heterosis was determined using t-test proposed by Wyne et al. (1970). RESULTS AND DISCUSSION Days to Tasseling Means and heterotic effects for days to tasseling of white QPM lines are given in Table I. Negative estimates of heterosis are preferred for days to tasseling in maize hybrids, because it leads to earliness and especially saves the spring crop from pollen desiccation due to rise in temperature during the month of May. The white QPM lines as well as their F 1 hybrids took comparatively more days to tasseling at than at. Days to tasseling of QPM lines and F 1 hybrids ranged from 49.0 to 54.2 at vs to 57.7 at Table I. The white QPM line NC1QW13 took minimum days to tasseling both at and. Among the F 1 cross combinations, NC1QW13 NC1QW1 displayed the minimum days to tasseling at both test locations. Two of the 12 F 1 hybrids expressed desirable negative mid and better parent heterosis for tasseling at. In contrast, three F 1 hybrids showed the desirable negative best parent heterosis at. Similar results about negative heterotic patterns for days to tasseling are reported by Flint-Garcia et al. (2009), Singh and Gupta (2009), Dickert and Tracy (2002), Gupta and Nagda (2000) Mendoza et al. (2000) and Saleh et al. (2002).

3 Sarhad J. Agric. Vol.27, No.3, Table I Means and heterotic effects for days to tasseling in white QPM at and Parents/Crosses Means MPH BPH Means MPH BPH Days % Days % NC1QW NC1QW NC1QW NC1QW NC1QW1 NC1QW * 4.0 * NC1QW1 NC1QW * 4.8 * NC1QW1 NC1QW * -0.3 NC1QW3 NC1QW * 4.3 * NC1QW3 NC1QW * 7.6 * * 3.0 NC1QW3 NC1QW * * 4.9 * NC1QW5 NC1QW * 5.3 * NC1QW5 NC1QW * 6.6 * * 5.2 * NC1QW5xNC1QW * 2.4 NC1QW13 NC1QW NC1QW13 NC1QW * NC1QW13 NC1QW * Location mean LSD (0.05) for location means = 0.87; LSD (0.05) for G x L means = 1.89 * P < 0.05 MPH = Mid-parent heterosis BPH = Best-parent heterosis Days to Silking Negative heterosis is also desirable for days to silking because it is an indication for early maturity. Means and heterotic effects for days to silking of white QPM lines and their hybrids are given in Table II. The white QPM lines as well as their F 1 hybrids took comparatively more days to silking at than. Days to silking of parents and F 1 hybrids ranged from 50.5 to 56.2 at vs to 62.5 at Table II. The white QPM line NC1QW13 took minimum days to silking both at (50.5) and (57.5). Cross combinations of NC1QW13 NC1QW3 and NC1QW1 NC1QW13 displayed the minimum days to silking at and. One of the 12 F 1 hybrids expressed desirable negative mid and better parent heterosis for silking at. In contrast, two F 1 hybrids showed the desirable negative best parent heterosis at. These results are in accordance with those of Tollenaar et al. (2004) who reported mean heterosis up to -7% for days to silking in maize. Similarly, Alam et al. (2008), Dickert and Tracy (2002), Saleh et al. (2002), Gupta and Nagda (2000), Mendoza et al. (2000), and Vasal et al. (1993a) have reported varying degrees of negative heterotic effects for days to silking in maize hybrids. Table II Means and heterotic effects for days to silking in white QPM at and Means MPH BPH Means MPH BPH Days % Days % NC1QW NC1QW NC1QW NC1QW NC1QW1 NC1QW * 3.8 * NC1QW1 NC1QW * 2.5 * * 4.5 * NC1QW1 NC1QW * NC1QW3 NC1QW * 3.8 * NC1QW3 NC1QW * 4.1 * NC1QW3 NC1QW * 1.9 * * 4.2 * NC1QW5 NC1QW * 5.0 * NC1QW5 NC1QW * 6.3 * * 4.7 * NC1QW5xNC1QW * 1.9 * * 2.0 NC1QW13 NC1QW * NC1QW13 NC1QW NC1QW13 NC1QW * 2.2 * Location mean LSD (0.05) for location means = 0.56; LSD (0.05) for G x L means = 2.07 * P < 0.05 MPH = Mid-parent heterosis BPH = Best-parent heterosis

4 Ikramullah et al. Hetrerotic effect for yield and protein content in white quality maize 406 Biological Yield Biological yield of white QPM parental lines and their hybrid progeny ranged from 8127 to kg ha -1 and to kg ha -1 at vs to kg ha -1 and to kg ha -1 at, respectively. A thorough study of the results indicated that the average biological yield at was higher than at. The estimates of mid and best-parent heterosis for biological yield were positive for all F 1 hybrids Table III. The magnitude of mid and better parent heterosis varied from cross to cross. The magnitude of heterotic effects regarding biological yield ranged from to and 8.03% to 82.42% against their mid and better parental values, respectively in crosses at. The F 1 hybrid of NC1QW3 NC1QW1 displayed highest heterosis over mid parent (98.82%) as well as over better parent (82.42%) at. At, all the F 1 hybrids showed positive mid and best-parent heterosis for biological yield. The magnitude of heterotic effects at regarding biological yield ranged from to 99.95% and to 94.62% against the mid and better parental values, respectively. The same cross combination of NC1QW3 NC1QW1 displayed the highest mid-parent (99.95%) and best-parent heterosis (94.62%) at, respectively. Similar results about heterotic effects for biological yield in different cross combinations of maize hybrids have been reported by Tomov (1988), Misevic (1989), Vasal et al. (1992 a), Arias and Souza (1998), Chalyk and Chebotar (1999), Konak et al. (1999), Rosa et al. (2000), Gyenes-Hegyi et al. (2002) and Singh and Gupta (2009). Table III Means and heterotic effects for biological yield in white QPM at and Parents/Crosses Means MPH BPH Means MPH BPH Kg ha -1 % Kg ha -1 % NC1QW NC1QW NC1QW NC1QW NC1QW1 NC1QW * * * * NC1QW1 NC1QW * * * NC1QW1 NC1QW * * * * NC1QW3 NC1QW * * * * NC1QW3 NC1QW * * * * NC1QW3 NC1QW * * * * NC1QW5 NC1QW * * * * NC1QW5 NC1QW * * * * NC1QW5xNC1QW * * * * NC1QW13 NC1QW * * * * NC1QW13 NC1QW * * * * NC1QW13 NC1QW * * * * LSD (0.05) for location means = ; LSD (0.05) for G x L means = * P < 0.05 ** P < 0.01 MPH = Mid-parent heterosis BPH = Better-parent heterosis Grain Yield The ultimate goal of plant breeding program is development of high yielding genotypes. Grain yield of white QPM lines and their resultant F 1 hybrids was generally higher at than Table IV. However, mid and best-parent heterotic effects for grain yield were greater in magnitude at than. Grain yield of parental lines ranged from 1951 to 3934 kg ha -1 at vs to 4435 kg ha -1 at. Similarly, grain yield of white QPM F 1 hybrids ranged from 4214 to 5758 kg ha -1 and 5093 to 6597 kg ha -1 at and, respectively. Thus, all hybrids were high yielding than their respective parental inbred lines. High yielding white QPM line at was NC1QW13 (3934 kg ha -1 ), while NC1WQ3, having lowest yield at, was the highest yielding line (4435 kg ha - 1 ) at. Among F 1 hybrids, NC1QW5 NC1QW13 was high yielding at (5758 kg ha -1 ), while its reciprocal cross NC1QW13 NC1QW5 ranked first for grain yield at (6908 kg ha -1 ). Maximum mid (112.1%) and bestparent (77.4%) heterosis for grain yield at was observed for cross combination NC1QW3 NC1QW1. At, cross combination NC1QW13 NC1QW5 expressed the maximum mid and best parent heterosis of 66.0 and 63.5% for grain yield, respectively. Similar ranges of heterotic effects for grain yield in different cross combinations of maize hybrids have been reported by Tomov (1988), Tokatlidis et al. (1999), Cheres (2000), Souza and Pinto (2000), Iqbal et al. (2001), Joshi et al. (2002) Soengas et al. (2002) and Venugopal et al. (2002).

5 Sarhad J. Agric. Vol.27, No.3, Table IV Means and heterotic effects for grain yield in white QPM at and Parents/Crosses Means MPH BPH Means MPH BPH kg ha -1 % kg ha -1 % NC1QW NC1QW NC1QW NC1QW NC1QW1 NC1QW * 54.0 * * 14.8 * NC1QW1 NC1QW * 59.1 * * 33.8 * NC1QW1 NC1QW * * 22.9 * NC1QW3 NC1QW * 77.4 * * 42.9 * NC1QW3 NC1QW * 59.4 * * 48.7 * NC1QW3 NC1QW * 24.0 * * 46.5 * NC1QW5 NC1QW * 60.9 * * 49.0 * NC1QW5 NC1QW * 35.6 * * 42.2 * NC1QW5xNC1QW * 46.4 * * 46.4 * NC1QW13 NC1QW * 29.5 * * 37.4 * NC1QW13 NC1QW * 37.0 * * 19.3 * NC1QW13 NC1QW * 34.4 * * 63.5 * LSD (0.05) for location means = 368.6; LSD (0.05) for G x L means = * P < 0.05 ** P < 0.01 MPH = Mid-parent heterosis BPH = Better-parent heterosis Protein Content The mean and heterotic effects for grain protein content of QPM are presented in Table V. Grain protein content of QPM inbred lines and F 1 hybrids ranged from 8.9 to 10.3% at and 9.0 to 10.4% at. The F 1 hybrids of QPM expressed both positive and negative heterotic effect for grain protein content at as well as at. Significantly positive mid-parent ( %) and best-parent ( %) heterotic effects for protein content were noted for cross combinations NC1QW3xNC1QW5, NC1QWxNC1QW3 and NC1QW5xNC1QW13 at and, respectively. Similar results for protein content in maize kernel and heterotic effects in different cross combinations of maize hybrids have been reported by Lou et al. (2005). Table V Means and heterotic effects for protein content in white QPM at and Parents/Crosses Means MPH BPH Means MPH BPH g/100g % g/100g % NC1QW NC1QW NC1QW NC1QW NC1QW1 NC1QW * * * * NC1QW1 NC1QW * NC1QW1 NC1QW * * NC1QW3 NC1QW * NC1QW3 NC1QW * 6.00 * * 8.87 * NC1QW3 NC1QW * * NC1QW5 NC1QW * * * NC1QW5 NC1QW * 7.48 * * 7.09 * NC1QW5xNC1QW * 6.00 * * 8.17 * NC1QW13 NC1QW * * * * NC1QW13 NC1QW * * NC1QW13 NC1QW LSD (0.05) for location means = 0.14; LSD (0.05) for G x L means = 0.30 * P < 0.05 ** P < 0.01 MPH = Mid-parent heterosis BPH = Better-parent heterosis CONCLUSION AND RECOMMENDATIONS Maximum mid-parent heterosis of and 112.1% for biological and grain yield, respectively was observed for NC1QW3xNC1QW1 at. Similarly, at maximum mid parent heterosis for biological yield (99.95%) was observed for NC1QW3xNC1QW1, while for grain yield (66.0%), NC1QW13xNC1QW5 showed maximum mid parent heterosis. Highest mid parent heterosis 8.72 and 9.25% for grain protein content was observed

6 Ikramullah et al. Hetrerotic effect for yield and protein content in white quality maize 408 for NC1QW5xNC1QW3 and NC1QW3xNC1QW5. Thus these lines viz. (NC1QW5 and NC1QW3) can be utilized in future breeding programmes for development of maize genotypes with enhanced grain yield and protein content. Breeding efforts needs to be focused on the development of QPM inbred lines with better field performance and acceptable levels of protein quality and quantity. Inbred lines identified as good donors for protein and yield attributes can be utilized for the conversion of well-adapted normal maize genotypes into QPM counterparts. REFERENCES Alam, A.K.M.M., S. Ahmed, M. Begum and M.K. Sultan Heterosis and combining ability for grain yield and its contributing characters in maize. Bangladesh J. Agric. Res. 33(3): Arias, C.A.A. and C.L. Souza Jr Genetic variance and covariance components related to intra and interpopulation recurrent selection in maize (Zea mays L.). Genet. Molec. Biol. 21(4): Bjarnason, M. and S.K. Vasal Breeding of quality protein maize (QPM). Plant Breed. Rev. 9: Bressani, R Nutritional value of high-lysine maize in humans. In E.T. Mertz (ed.) Quality protein maize. Amer. Assoc. Cereal Chem, St. Paul, MN. Chalyk, S. and O. Chebotar Utilizing matemi haploids to identify major genes controlling plant height in maize. Czech J. Genet. P1. Breed. 35(3): Cheres, M.T., J.F. Miller, J.M. Crane and S. Knapp Genetic distance as a predictor of heterosis and hybrid performance within and between heterotic groups in sunflower. Theor. Appld. Genet. 100(6): Dickert, E.T. and F.W. Tracy Heterosis for flowering time and agronomic traits among early open-pollinated sweet corn cultivars. J. Amer. Soc. Hort. Sci. 127(5): FAO FAOSTAT. Food and Agric. Org. Rome, Italy. Fehr, W.R In: Principles of cultivar development. Theory and technique. Macmillan Publ. Co. Inc., New York, USA. Flint-Garcia, S.A., E.S. Buckler, P. Tiffin, E. Ersoz and N.M. Springer Heterosis is prevalent for multiple traits in diverse maize germplasm. Plos One. 4(10): Gupta, S.C. and A.K. Nagda, Analysis of variety diallel cross for yield and its components in winter maize (Zea mays L.). Indian J. Genet. Pl. Breed. 60(3): 30I-303. Gyenes-Hegyi, Z.I. Pok, L. Kizmus, Z. Zsubori, I. Nagy and L.C. Marton Plant height and height of the main ear in maize (Zea mays L.) at different locations and different plant densities. Acta Agron. Hungarica. 50(1): Hallauer, A.R. and J.B. Miranda Quantitative genetics in maize breeding. Iowa State Univ. Press. Ames, IA. Iqbal, M., M. Saleem and O. Rashid Inter-racial heterosis in maize hybrids. Pak. J. Scient. Indust. Res. 44: Joshi, V.N., N.K. Pandiya and R.B. Dubey Heterosis and combining ability for quality and yield in early maturing single cross hybrids of maize (Zea mays L.). Indian. J. Genet. Pl. Breed. 58(4): Knabe, D.A., J.S. Sullivan, K.G. Burgoon and A.J. Bockholt QPM as swine feed. Amer. Assoc. Cereal Chem Konak,C., A. Unay, H. Basal and E. Sorter Combining ability and heterotic effects in some characteristics of second crop maize. Turkish J. Field Crops. 6(2): Lou, X., J. Zhu, Q. Zhang, R. Zang, Y. Chen, Z. Yu and Y. Zhao Genetic control of the opaque-2 gene and background polygenes over some kernel traits in maize (Zea mays L.). Genetica. 124: Mendoza, M., A. Oyervides and A. Lopez New maize cultivars with agronomic potential for the humid tropics. Agronomia Mesoamericana. 11(1): Misevic, D Hetrotic patterns among US Corn Belt Yugoslavian and exotic maize populations. Maydica. 34(4): National Research Council Quality protein maize. National Acad Press, Washington, DC, USA. Pereira, L.M.A The economics of quality protein maize as an animal feed: Case studies of Brazil and El Salvador. CIMMYT Econ. Working Paper CIMMYT, Mexico. Rosa, A. H. de Leon, G. Martinez and F. Rincon Heterosis, combining ability and genetic diversity in commercial hybrids of maize (Zea mays L.). Agronomia Mesoamerican. 11(1): Saleh, G.B., D. Abdullah and A.R. Anuar Performance, heterosis and heritability in selected tropical maize single, double and three-way cross hybrids. J. Agric. Sci. 138(1):

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