Multivariate analysis of various agronomic traits in grasspea (Lathyrus spp.) germplasm.

Diversity among 368 accessions of grasspea (Lathyrus sativus) from diverse indigenous and exotic sources was assessed for various agronomic traits. Analysis of variance for quantitative traits revealed that all accessions were significantly different and a wide range of variability exists  for most of the traits studied. Association studies revealed that seed yield had positive significant correlation with most of the traits studied. Cluster analysis using Wards method classified 368 populations into 19 distinct groupings. A large number of genotypes were placed in cluster I(36 genotypes) followed by cluster II and cluster III each with 34 accessions. The maximum inter-cluster distance was observed between clusters XII and XII indicating the possibility of high heterotic effect if the individuals from these clusters are cross-bred. The estimates of eigen value associated with the principal components and their respective relative and accumulated variances explained 49.77% of total variation in the first two components. The characters with highest weight in component first were seed yield/plant, pods/plant, biological yield and seeds/pod which explained 38.11% of total variance. The results of principal component analysis were closely in line with those of the cluster analysis. The study of diversity reflects that in the present set of germplasm , ample amount of genetic variation exists for seed yield and other yield components suggesting direct selection for seed yield and indirect selection based on other component traits for the development of high-yielding varieties in grasspea.