Evaluating the variability parameters among rice (Oryza sativa. L) landraces and varieties from Tamil Nadu

Rice is one of the major food crops which is being most explored for continuous improvement to feed the growing population. In view of this, forty-three rice landraces and varieties from Tamil Nadu were subjected to variability and principal component analyses with fifteen quantitative traits and eight qualitative traits. For the variability parameters a higher PCV, GCV with high heritability and genetic advance was observed for all the traits. This indicated the presence of additive gene action and effective selection could be carried out for all traits in future breeding programs. Subsequently, from the principal component analysis five reliable PC’s with eigen values greater than one was attained. PC1 explained a total variability of 28.53% followed by PC2 which exhibited 16.99% of the variability. The major positive contributions towards the variability across PC’s were established by days to 50% flowering, plant height, flag leaf length, culm length, days to maturity, leaf width, panicle length, number of tillers, number of productive tillers, seedling height and grain width. Among all, Sornamasuri and JGL were found to be desirable for yield attributing traits from the PCA biplots and these genotypes could be evaluated for their similar performance in other breeding programs for utilization. Further among all qualitative traits, grain colour and leaf blade colour were observed to be variable among the landraces and they could be utilised as key morphological markers for identifying true to type varieties in future.