Genetic divergence among mutant genotypes of greengram [Vigna radiata (L.) Wilczek

Abstract

The nature and magnitude of genetic divergence was estimated among forty five mutant lines of greengram variety OBGG-52, developed by single and combination treatments with gamma rays, Ethyl Methane Sulphonate (EMS), N-methyl-N¢-nitrosoguanidine (NG) and maleic hydrazide (MH) using multivariate analysis. These mutant genotypes were grouped in to 12 clusters based on D2 values using Tocher’s method. A large proportion of mutant lines showed divergence from the parent variety and also among themselves. No definite relationship of mutagenic origin and clustering of mutant lines were observed. The mutant lines developed from the same mutagenic treatments often grouped into different clusters indicating that each mutagenic treatment was effective in inducing diverse types of changes in the nine traits studied. Sixteen genotypes were grouped with their parents in cluster-I, while rest of 28 genotypes grouped in to another eleven divergent clusters. Cluster-IV had maximum intra-cluster distance (3.95), while inter-cluster distance was highest (8.27) between cluster-XI and cluster-XII. Genotype of Cluster-III was superior for yield per plant, seeds/pod where as Cluster- VIII was superior for 100-seed weight and pods per plant. Thus hybridization of genotype belonging to cluster-III with genotype in cluster-VIII is suggested for development of superior genotypes.