Determination of Genetic Variability and Diversity in Bread Wheat for Yield and Yield Contributing Traits

A study was conducted to estimate genetic variability and genetic divergence for 8 traits in 52 diverse genotypes of bread wheat (Triticum aestivum L.) under normal sowing condition. For all of the features studied, the analysis of variance revealed extremely significant differences in mean square owing to genotypes. Grain yield per plot and tillers per meter have high genotypic and phenotypic coefficients of variation. High heritability coupled with high genetic advance as percent of mean was observed for grain yield/plot and tillers/meter and plant height. Genetic divergence was assessed by Mahalanobis D2 statistic, which grouped 52 genotypes into seven clusters. Maximum genetic divergence was observed between cluster V and VI followed by that between VI and VII (D=34.61). Cluster IV had desirable rating for spike length, spikelets/spike, thousand grain weight and yield/plot. Cluster VII had desirable rating for tillers/meter and had highest contribution towards total genetic divergence.