Multivariate approach to analyse genetic diversity in some basmati rice genotypes ( Oryza sativa L.)

Twenty three genotypes of basmati representing the broad spectrum of variation were assessed for ten yield attributing characters and ten quality characters using principal component analysis and cluster analysis. Principal component analysis identified five principal components with eigen values more than one for four components which contributed 90.40 per cent of the cumulative variance. The genotypes were grouped into six clusters by using cluster analysis. Cluster II was the largest, consisting of six genotypes followed by five genotypes each in clusters III, IV and V, two genotypes each in clusters I and VI. The results indicated that there was some degree of similarity of genotypes clustered together on the basis of their origin. However, the pattern of distribution of some genotypes from different eco-geographical regions was found random, indicating that geographical diversity and genetic diversity were not related. The maximum intra cluster distance was observed for the cluster III. The highest genetic divergence was observed between the clusters IV and III exhibiting wide diversity. Among different traits, plant height, days to 50% flowering, spikelets per panicle, KLAC and amylose content had maximum contribution towards total divergence may be used as selection parameters in segregating generations. Judicious selection of genotypes from the clusters may be used as potential donors for future hybridization programmes to develop varieties and hybrids of high yield without much compromise on quality.