One hundred and nineteen rice breeding lines with two local checks were subjected to the principle component analysis (PCA) and cluster analysis to estimate the existing genetic diversity for yield contributing characters. The first three principal components having Eigen value more than one are cumulatively contributing 68.69% to the total variability. PC1 has the contribution from the traits days to 50% flowering (0.497), days to maturity (0.484) and ear bearing tillers (0.359) which accounted 31.84% of total variability indicating these traits contributed more to the total variance. Cluster analysis revealed that the rice lines were classified into 12 divergent clusters by both PCA and Tocher's method. Among the 12 clusters, cluster 1 had highest number of breeding lines (18) and cluster 11 had least number of lines (2) in PCA cluster analysis whereas in Tocher's method highest number of lines observed in cluster 5 (34) followed by cluster 1(33). This analysis reveals the presence of wide genetic variance in rice breeding lines.

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Principal component analysis was carried out to assess the diversity among 107 rice genotypes with regards to anaerobic germination tolerance traits. Results revealed three principal components with eigen value > 1. These components contributed for a total variability of 75.780 per cent. Component 1 (PC 1) had contributed maximum 27.288 per cent while PC 2 had contributed to 26.060 per cent and PC 3 had contributed to 22.331 per cent towards the total variability. The characters, namely, anaerobic response index and germination per cent explained maximum variance in PC 1. The results of 2D scatter diagram revealed maximum diversity for MTU 1140. Hybridization of MTU 1140 with MTU 1010, identified as widely diverse genotypes in the study is expected to result in high yielding transgressive segregants with high yield and tolerance for germination under anaerobic conditions.