Genetic diversity among rice varieties cultivated in Punjab

The assessment of genetic diversity among the rice varieties cultivated in Punjab was done using Mahalanobis D2 statistics based on eleven agro-morphological traits. Nineteen cultivars were grouped into four different clusters revealing sufficient amount of variability among the genotypes. The clustering pattern revealed non correspondence of geographic diversity with genetic divergence. Days to 50% flowering and plant height contributed considerably, accounting for 61% of total divergence. The highest inter-cluster divergence (76.33) between clusters I and II maybe utilized in heterosis as well as in recombination breeding. Further, selection within cluster IV, having maximum intra-cluster distance (11.64), maybe exercised based on the highest mean for the desirable traits, which could be used for improvement through inter-varietal hybridization.