COMBINING ABILITY AND NATURE OF GENE ACTION IN SESAMUM (SESAMUM INDICUM L.)

Transcription

1 Indian J. Agric. Res., 43 (2) : , 2009 AGRICULTURAL RESEARCH COMMUNICATION CENTRE COMBINING ABILITY AND NATURE OF GENE ACTION IN SESAMUM (SESAMUM INDICUM L.) H.P. Mishra, R.C. Misra and P.K. Sahu Department of Plant Breeding and Genetics, Orissa University of Agric. and Technology, Bhubaneswar , India. ABSTRACT Combining ability and nature of gene action involved in the inheritance of seed yield and its components in sesamum were analyzed in F1 of a half diamel cross among1-2 elite varieties of diverse origin. Varieties VRI-l and GT-tO were good general combiner for capsules/, Kalika and HT-I, for seeds/capsule, AKT-64 and Pragati, for 1Ooo-seed weight and Uma, GT-IO, Akt-64 and Kalika were good combiner for seed yield. Gene action was largely additive for primary branc,hes and predominantly additive for height and looo-seed weight. Both additive and non-additive gene action were equally important for days to maturity and seeds/capsule. Additive gene action played a greater role in case of capsules/, while non-additive gene action played a greater role in inheritance of seed yield. Key words : Combining ability, Gene action, Sesamum. INTRODUCTION Evaluation for combining ability helps in identifying superior parental stocks for use in hybridization programme for improvement of productivity. Information on nature ofgene action involved in inheritance of quantitative traits helps in deciding appropriate breeding method and efficient selection procedure. The present study was undertaken to evaluate the combining ability twelve elite varieties of sesamum and analyze the nature ofgene action involved in inheritance of seed yield and its component traits. MATERIAL AND METHODS The material consisted of a 12-parent half diallel cross. The parental varieties included 3 improved varieties (Prachi, Uma and Kalika) of Orissa and 9 improved varieties (GT-10, VRI-1, B. 67,TKG-22, TC-25, RT-46, Prgati, AKT-64 and HT-1) from nine other states. The F1 of the 66 crosses along with parents were grown in RBD with 4 replications during summer, Each entry was represented by one row of 2.5 m length in each replication. Sowing was done at a spacing of 35 cm x 10 cm and with normal agronomic practices. Observation on days to maturity was taken on plot basis and observation on other characters viz., height, number of primary branches, number of capsules/, number of seeds/capsule, 1000-seed weight and seed yield/ were recorded on 8 random s per plot. Analysis of variance was carried out on plot mean values for all characters. Combining ability analysis was done following Griffing (1'956). GCA variance (a2gea) and SCA variance (cr 2 sea) were estimated and the nature of gene action was ascertained

2 120 INDIAN JOURNAL OF AGRICULTURAL RESEARCH. on the basis of these components of genetic maturity. Six varieties had significant positive variation. and five had significant negative GCA effect RESULTS AND DISCUSSION for height. Kalika, GT-10 andvri-1 were There were significant differences good general combiners for height and among the parents and F hybrids for all the 7 TC-25, HT-1 and TKG-22 ranked low in this characters studied. Me~ns of the parental respect. Four varieties had signifkal1t positive varieties ranged from 75.0 to 81.5 for days to and six had significant negative effect for maturity, to cm for height, primary branches. VRI-1 and Prachi were 1.44 to 3.57 for primary branches, to good combiners for primary branches and for capsules/, to for TKG-22 andpragati ranked low in this respect. seeds/capsule, 2.94 to 3.60 g for 1000-seed Five varieties had significant positive weight and 3.96 to 7.62 g for yield per. and five had significant negative GCA effect Among the hybrids, the range was for capsules/. VRI-1 was the best general for days to maturity, cm for combiner for capsules/, followed by GTheight, forprimarybranches, , Prachi, and Uma, whereas TKG- 22 and for capsules/, for TC-25 ranked low in this respect. Two varieties seeds/capsule, g for 1000-seed had significant positive and three had weight and g for yield per. significant negative GCA effect for seeds/ Better performance of the hybrids for yield capsule. Kalika and HT-1 were good general components, especially capsules/ and combiners for seeds/capsule and VRI-1 and seeds/capsule, compared to the parental Pragati ranked low in this respect. Four varieties is well reflected in yield performance varieties had significant positive and five had of hybrids. significant negative GCA effect for 1000-seed Combining ability : There were significant weight. AKT-64 and Pragati were good general differences in GCA of parents for au the combiners for 1000-seed weight, followed by characters studied (Table 1). There were also GT-10, whereas Kalika, Prachi and B. 67 significant differences in SCA of crosses for ranked low in this respect. Four varieties had all characters except 1000-seed weight. Five significant positive and two had significant varieties had significant positive and three had negative GCA effect for yield. Uma and GTsignificant negative GCA effect for days to 10were good combinersfor yield, followed by maturity (Table 2). TC-25, TKG-22 and HT-1 AKT-64 and Kalika, whereas TC-25 and TKGwere good general combiners for early 22 ranked low in this respect. Table 1. ANOVA and combining ability for 7 characters in F 1 of a 12 parent half diallel cross in sesamum Mean Squares Source Genotypes GCA SCA Error d.f ** Significance at 1% level. Days to maturity 1.286** 3.960** 0.840** Plant height ** ** 28.99** Primary branches Capsules! 0.263** 81.87** 1.212** ** 0.105** 41.34** Seeds! capsule 20.44** 61.27** 13.64** seed weight 0.034** 0.190** Yield! 1.57** 3.89** 1.18** 0.45

3 Vol. 43, No.2, 2009 Table 2. GCA effects of the parental-;1rieties for 7 characters L: F 1 of a 12-parent half diallel cross in sesamum Character/ Days to Plant ht Primary parent maturity (em.) branches Prachi ** Uma 0.34** 2.01 * 0.245** Kalika 0.59** 10.66** Gr-lO 0,.40** 8.90** 0.248** VRI ** 8.83** 0.488** B ** TKG ** -7.55** ** TC ** ** ** RT ** ** Pragati ** ** AKT ** 3.03** ** Hr ** -8.40** ** SE (g) SE (gl-g) *Significance at 5% level. ** Significance at 1% level. Four crosses showed significant positive and seven crosses showed significant negative SCAeffectfordaystomaturity(Table3).Seven crosses showed significant positive and two crosses showed significant negative SCA effect for height. Positive SCA effect for the character was high in 3 crosses. For primary Capsules! 4.02** 3.44** 2.27* 4.53** 9.31 ** ** -5.40** -3.50** ** -3.40** Seeds! capsule ** ** ** ** ** seed wt. (g) ** *:~ 0.105** ** ** ** 0.153** 0.199** 0.067** Yield! (g) ** 0.39* 0.66** ** -0.95** ** for yield. Positive SCA effect for yield was high (>1.75 g /) in 3 crosses (PrachiffC-25, PragatilHT -1, VRI-l/AKT-64) and moderate in 5 crosses. The SCA effects for productivity traits indicated significant difference in genetic properties and breeding potential ofthe cross. Nature of gene action : Nature of gene branches, two crosses showed significant action was analyzed in terms of 0'2 and cr2 positive and one cross showed significant The GCA component 0'2 co~tains t~ gea negative SCA effect, all of moderate variance due to additive effect and a portion magnitude. Eight crosses showed significant of that due to additive x additive epistasis, both positive and two crosses showed significant of which are flexible. The SCA component negative SCA effect for capsules/. Positive 0'2 includes the variance due to dominance sea SeA effect for the character was high (> 10 and epistasis involving dominance such as capsules/) in three crosses (PrachiffC-25, additive x dominance and dominance x PrachilHT-1, B.67/TC-25) and moderate (8- dominance interactions and represents the 10) in 5crosses. Eight crosses showed non-fixable component of genetic variance. significant positive and three crosses showed The nature of gene action involved in significant negative SCA effect for seeds/ inheritance of a character was inferred from capsule. Positive SCA effect for the character the relative proportionsof 20'2gea asthe additive washigh(>5seeds/capsule)in4crosses.sca genetic variance (O' 2 A ) and O'2 sca as the noneffect was minimal for 1000-seed weight. Nine additive genetic variance (0'2NA)' Estimates of crosses showed significant positive and two components of variance for the 7 characters crosses showed significant negative SeA effect studied are presented in Table 4. GCA

4 122 INDIAN JOURNAL OF AGRICULTURAL RESEARCH Table 3. Range of SCA effects and number of crosses showing significant SCA effect in F 1 of a 12-paren~ half diallel cross in sesamum. Character SCA range No. of No. of Crosses showing positive SCA effects crosses crosses with with negative positive SCA SCA Days to maturity Plant height (em) Primary branches Capsules/ Seeds/capsule looo-seed wt. (g) Yield/(gl AKT-64/ HT-1, Pragati / HT-I, GT-IO / TC-25, RT-46/ HT-I Prachi/TC-25, VRI-lIAKT-64, Kalika/ GT-IO, Prachi/Kalika, GT-lO/TC-25, B.67/ HT-I, VRI-I / Pragati VRI-I / AKT-64, B.67 / TKG-22 Prachi / TC-25, Prachi / HT-I, B.67/ TC-25, Prachi / Kalika, Kalika / GT-lO, VRI-I / Pragati, VRI-I / AKT-64, Uma/TKG-22 Pragati / HT-I, Kalika / Pragati, VRI-I / TKG-22, Uma/ AKT-64,Kalika/TC-25, GT-IO / B 67, RT-46/ HT-I, VRI-I / AKT-64 GT-10/TKG-22, TKG-22/ AKT-64, Pragati / AKT-64, B.67 / RT-46 Prachi / TC-25, Pragati / HT-I, VRI-1 / AKT-64 J 8.67/ RT-46, Uma / TKG-22, Prachi/ GT-lO, Uma/ AKT-64, B.67 / Pragati, 8.67/ TC-25 component (2cr2gca) constijuted 43% at' SCA nature of gene action was largely additive component (0'2 ) constituted 51% of the for the character. This is in agreement sea genetic variance for days to maturity, indicating with those of Das and Gupta (1999) and that additive and non-additive gene action Devasena et al. (2001). were equally important in the inheritance of The GCAcomponent constituted 64.1% the character. This is in agreement with those and SCA component constituted 35.9% of of Goyal and Kumar (1991). In case of genetic variance for capsules/, indicating height, GCA component was much larger,. that additive gene action played a greater role (86.4%) than SCA component (13.6%), than non-additive gene action in the indicating that! the nature of gene action was inhe-ritance of the character. This is in predominantlyadditivefor the character. This agreeme11,t with those of Devasena et a/. is in agreement with those of Siddique et al. (2001), Sanl5.ar and Kumar (2003) and I I (2003), Sabu et al. (2004) and Singh (2004). Siddique eta/. (2003). In case ofseeds/capsule, In case of primary branches also, the GCA the GCt; c<pmbonent constituted 44.5% and componentwas much larger (78.6%) than SCA SCA co~stituted 55.5% of genetic variance, component (21.4%), indicating that the indicating that both additive and non-additive

5 Vol. 43, No.2, Table 4. Variance components and he;"~ability (h 2 ) estimates in ~1 of a 12-parenthalfdiallel cross in sesamurn. Character cr 2 cr2 sca cr2 e cr2* cr 2 * gca A NA h 2 (%) Days to maturity Plant height (cm) Primary branches Capsules / Seeds / capsule seed wt. (g) Yield / (g) *cr 2 =2cr 2 cr 2 = cr 2 cr 2 = cr 2 + cr 2 A gca' NA sea' G A NA gene action were equally important in the inheritance of the character. This is in _ agreement with those of Fatteh et aj. (1982) and Dikshit and Swain (2001). The GCA component constituted 96.3% of genetic variance for 1000-seedweight, indicating that the nature of gene action for the character is almost entirely additive. This is in agreement with those of Dikshit and Swain (2001), Sabu et aj. (2004), Singh (2004) and Vidyavathi et aj. (2005). The SCA component constituted 65.1% and GCA component constituted 34.9% of genetic variance for seed yield, indicating that REFERENCES Babu, D.R. eta/. (2004). J. Oilseed Res., 21: Das, S. and Gupta, T.D. (1999). Indian J. Genet. 59: Devasena, N. etal. (2001). J. Oilseed Res., 18: Dikshit, U.N. and Swain, D. (2001). J. Oilseed Res., 18: Fatteh, U.G. eta/. (1982). MadrasAgric. J. 69: Goyal, S.N. and Kumar, S. (1991). Indian J. Genet. 51: Griffing, B. (1956). Aust. J. BioI. Sci., 9: Sankar, P.O. and Kumar, C.RA (2003). Indian J. Agric. Res., 37: Siddique, MA et al. (2003). PKV Res. J., 27:1-6. Singh, P.K. (2004).J. Oilseed Res., 21: Vidyavathi, R. etal. (2005). Indian J. Agric. Res., 39: non-additive gene action played a greater role than additive gene action in the inheritance of the character. This is in agreement with those ofsankar and Kumar (2003), Sabu et al. (2004), Singh (2004) and Vidyavathi et aj. (2005). Heritability estimates (h 2 bs ) ranged from 70.98% for seed yield to 90.75% for heignt (Table.4). The h 2 estimates indicated substantialgeneticvariation in the material for all the characters. Combining ability analysis and gene action for the productivity traits in the diallel cross showed thatthe material offers ample scope for selection and utilization of selected crosses in breeding for yield.