Genetic Diversity Studies in Rice Landraces (Oryza sativa L.) Based on Mahalanobis D2 Distance

Abstract

The present investigation was carried out to assess the genetic diversity present among 66 rice landraces along with 4 checks for 14 different quantitative traits. All the genotypes were grouped into 5 clusters by performing Tocher’s clustering method using Mahalanobis D2 distance. Cluster I was the largest, comprising of 34 genotypes, followed by Cluster II with 28 genotypes. The maximum genetic distance (D2) was observed between cluster V an III (6243.98), followed by clusters II and III (6166.44), clusters IV and II (6022.47), clusters I and IV (4544.26) and clusters IV and III (4161.67). The results revealed the highest contribution of plant height (25.50%) towards total diversity, followed by days to 50% flowering kernel (3.18%), grain yield per plant (2.42 %) and days to maturity (2.06). The rice genotypes belonging to the clusters III , IV and V were found to be the most divergent, and hence can be utilised in the recombination breeding programmes to exploit maximum heterosis.