Deepak Barfa, M.K. Tripathi, V. S. Kandalkar, J.C. Gupta and Gyanesh Kumar
Abstract
An experiment was laid out in randomized block design with eight lines, five testers and their 40 hybrids of Indian mustard. Lines, tester and L X T variances showed that both additive and non-additive components of variances were significant but magnitude of non-additive components were higher as compared to additive components for all characters investigated except number (s) of primary branches per plant, indicating predominance of non-additive gene action for the almost parameters. The parents MRNJ-89, MRNJ-94 and JM-2 were recognized as good general combiners for seed yield and its attributing traits. Only 10 crosses viz:âMRNJ-71 X JM-1, MRNJ-79 X RVM-2,âMRNJ-86 X RVM-2, MRNJ-89 X RVM-1, MRNJ-89 X JM-3, MRNJ- 93 X JM-2, MRNJ-94 X JM-2, âMRNJ-95 X RVM-2, âMRNJ-101 X JM-1 and âMRNJ-101 X RVM-2 showed significant positive SCA effect for seed yield and its attributing traits, whereas, hybrids âMRNJ-94 X JM-2â, âMRNJ-89 X RVM-1âand âMRNJ-89 X JM-3âexhibited highest SCA effects along with higher magnitudes of heterosis over both better and standard parents. Considering mean performance, heterosis and combining ability effects, parents namely: MRNJ-89, MRNJ-94 and JM-2 and the hybrids âMRNJ-94 X JM-2â, âMRNJ-89 X RVM-1âand âMRNJ-89 X JM-3â were found to be promising for exploitation of heterosis. Cross combinations MRNJ-94ÃJM-3, MRNJ-79ÃJM-1, MRNJ-79ÃRVM-1 and MRNJ-94ÃJM-1 were found resistant against white rust and MRNJ-79ÃJM-1 and MRNJ-94ÃJM-3 against Aternaria blight. The additive as well as non-additive gene effect can be exploited by the adopting breeding procedures involving bi-parental mating followed by sufficient cycles of recurrent selection.