Mahalanobis D2 and principle component based genetic divergence, selection criteria and genetic variability studies in cold tolerant rice (Oryza sativa) genotypes

The present investigation was carried to assess the genetic variability, trait relationship, path analysis, D2 analysis and principal component analysis in thirty eight genotypes. All the traits under this study shown the significant difference for ANOVA and high GCV and PCV is observed for Panicle exertion and seed yield per plant. High heritability coupled with high genetic advance as per cent mean was observed for seed yield per plant and tillers per plant. All the characters except test weight showed the positive and significant correlation with seed yield at phenotypic level. Path analysis revealed that filled grains per panicle and spikelet fertility showed positive direct effect on seed yield. Diversity studies indicated that inter cluster distance was maximum between cluster II and VII followed by cluster II and VI & cluster I and VII. Principle component analysis indicated that first five principal components contributed to 85.81% of the total diversity is contributed by plant height, seed yield per plant, spikelet fertility, panicle exertion, panicle length, filled grains per panicle and tillers per plant. Selection based on the results of the present study could be exploited in designing future plant breeding programmes for development of high yielding cold tolerant rice varieties.