Genetic diversity, variability and trait associations in rice (Oryza sativa L.) genotypes

This study assessed genetic divergence, variability and trait associations for 12 morphological characters in 30 rice (Oryza sativa L.) genotypes. Genetic divergence was estimated using Mahalanobis’ D² analysis. Genotype TKM 13 exhibited superior performance for traits such as days to 50 % flowering, plant height, number of productive tillers per plant, kernel length, kernel breadth, kernel L/B ratio and grain yield per plant. D² analysis revealed no clear relationship between geographic origin and genetic diversity. Traits including 100 grain weight, grain yield per plant and grain length contributed substantially to genetic divergence. High to moderate phenotypic (PVC) and genotypic (GCV) coefficient of variation, along with high heritability coupled with high genetic advance as a percentage of mean, were observed for traits such as grain L/B ratio, 100 grain weight and kernel traits. Most traits were predominantly controlled by additive gene action, indicating that selection would be effective for their improvement.