Assessment of Genetic Divergence in Brassica Germplasm

The objective of this study was to assess the genetic divergence available in Brassica germplasm based on Euclidean distances for the identification of genetically diverse and agronomically superior accessions from different Brassica species which may generate putative tansgressive segregates on hybridization. Based on results obtained in field experiments, designed in compact family block, for two consecutive years, wide physio-morphological divergence were obtained for all the traits under study, both within and between species (though the inter-specific variation was higher than intra-specific one). Principal component analysis, which transformed all the metric traits into single index of similarity, yielded eight eigen vector and eigen roots. Based on first five principal components (which accounted for 97.83% of the total variation), non-heirarchical Euclidean cluster analysis grouped the 36 Brassica genotypes into five well characterized groups (based on aggregate effect of si:nilarity in traits). Genotypes of each Brassica species grouped separately, depicting characteristic differences among species.