Studies on genetic divergence in rice germplasm lines

Abstract

Fifty four elite rice germplasm lines being maintained at Agricultural Research Station. Nellore were evaluated for their genetic diversity with regard to yield, yield components and quality trails. The genotypes were grouped into nine clusters, based on Mahalanobis D statistics. Geographical and genetic diversity were observed to be unrelated, as genotypes from diverse geographical regions were placed in the same cluster, while genotypes from the same centre were grouped into different clusters. Results on inter-cluster distances revealed maximum diversity between genotypes of clusters IV and VIII. Intra-cluster distance was maximum for Cluster V, indicating the existence of variability with in the cluster. A perusal of the results on cluster means revealed high yield, number of grains per panicle, panicle length, plant height and days to 50 per cent (lowering for Cluster IV, indicating the desirability of genotypes from the cluster for improvement of grain yield and the above yield components. Further, plant height and days to 50 per cent flowering, together accounted for 82.04 per cent of the total genetic divergence, indicating their importance in the choice of parents for hybridizalion programmes.