Genetic analysis for yield traits by using large seed mutants in mungbean (Vigna radiata L. Wilczek)

Abstract

Genetic analysis of quantitative traits of induced mutants is of importance in self-pollinated crops like mungbean which is lacking in desired genetic variation. In the present study, analysis of six partial diallel crosses involving four large seed mutants (5.5 to 6 g 100 seed weight) of Samrat was carried out to estimate general combining ability (gca), specific combing ability (sca), heritability in narrow sense and various genetic parameters which can explain the quantitative genetic variation for ten different quantitative traits. Both gca and sca effects were significant for different traits viz., plant height, primary branches plant-1, number of clusters plant-1, pods plant-1, 100 seed weight and seed yield plant-1, which indicated that both additive and dominance components of variances were important for governing these quantitative traits. The values of mean degree of dominance were significant and greater than one for all the traits indicative of over dominance. Higher proportions of dominant genes were found for all the traits except number of clusters plant-1. In the parents, higher proportions of negative genes were observed for all traits except number of pods plant-1. Significance of the variance component due to dominance deviation (H1) and variance due to dominance effects corrected for genes distribution (H2) clearly showed the possible changes in the genes governing these traits. Present study highlighted the contribution of micro-mutations in various traits simultaneously governed by large number of genes with their small and cumulative effects that were not conspicuous in terms of morphology of mutants.