Studies on genetic diversity in selected rice (Oryza sativa L.) landraces of Tamil Nadu

A total of 50 traditional rice landraces of Tamil Nadu were characterised for 12 biometric traits and the data were subjected to principal component analysis and cluster analysis to determine the contribution in variation, diversity level and the strength of association prevailing between grain yield and its related traits. Out of 12 Principal components, four exhibited more than 1.0 eigenvalues and contributed to 73.58 per cent of the total variability. PC1 alone accounts for about 39.15 per cent, while PC2, PC3, PC4 contributed 14.39, 11.00 and 9.04 per cent for total variability, respectively. Through agglomerative clustering, the landraces were grouped into five clusters. The landraces present in cluster I (G1, G18, G23, G26, G31, G32, G36, G39, G43, G44, G45) and cluster V (G30 and G45) were found to be with contrasting characters making them ideal parents for further utilization in rice breeding programmes. Key words: Rice, Landraces, Principal Component Analysis, Cluster Analysis