Study of genetic variation and broad sense heritability for some qualitative and quantitative traits in soybean (Glycine max L.) genotypes

The success of crop breeding programs largely depends on presence of the genetic variation and the inheritance of traits of interest. The importance of genetic variation assists the breeder to decide the proper strategy and selection criteria to be followed for improvement of the target traits. In addition, the correlation between seed yield and quality characters as well as oil content is of major interest. Twelve soybean genotypes were evaluated for genotypic variation, phenotypic correlations and broad sense heritability for seed yield and some quality properties during three growing seasons. Results showed significant differences for seed yield and quality characters which suggest sufficient genetic variation for efficient selection. High broad sense heritability (81%, 76%, 74%) and genetic advance (0.35, 0.20, 0.40) were obtained for the number of nodes plant-1, days to flowering and plant height respectively, and strong positive correlation (r = 0.61*) was observed between seed yield and plant height. An increase in plant height leads to increase of number of nodes plant-1, number of pods plant-1, number of seeds pod-1, number of seeds plant-1 and protein yield. It is, therefore, concluded that simultaneous selection for improving seed yield through increasing the number of nodes plant-1, number of pods plant-1 and plant height would be an effective approach to increase seed yield as well as protein yield.