Evaluation of Genetic Diversity in Soybean (Glycine max (L.) Merrill) Genotypes Based on Agronomic Traits

Twenty-seven soybean genotypes were assessed for twelve morphological traits in a randomized complete block design with three replications throughout Rabi season, 2014 at field laboratory of Sher-e-Bangla Agricultural University, Dhaka, Bangladesh. Significant variations were found among the genotypes for all the traits. Stover yield, seed yield, single pod weight per plant, 100-seed weight, number of branches per plant and number of pods per plant exhibited that they were governed by additive gene action and selection for the improvement of these characters would be fecund. The phenotypic variance was higher than the corresponding genotypic variance for all the characters. All the traits showed moderate to low phenotypic and genotypic coefficient of variation. The yield had significant positive correlations with number of branches per plant followed by stover yield and number of pod per plant. Number of branches per plant and stover yield had also the highest positive direct effect as well as significant and positively highest correlation with yield. Days to first flowering and number of pod per plant had negative direct effect on seed yield but they are significantly and positively correlated with yield. Considering genetic variability, correlation and path analysis emphasis should be given on the number of branches per plant, stover yield, number of pod per plant and single pod weight per plant during the breeding program to improve the seed yield of soybean.