Revealing genetic diversity of Indian mustard (Brassica juncea) for yield improvement

Abstract

The study was carried out during rabi 2015-17 to understand the nature and magnitude of genetic variability and character association of 45 accessions of Indian mustard. These accessions were evaluated for 16 quantitative traits under standard package of practices. The results indicated high PCV and GCV for 1000 seed weight, stover nitrogen uptake (STNU) and seed nitrogen uptake (SNU) while it was low for NUE. High heritability coupled with high genetic advance as percent of mean was observed for 1000 seed weight, STNU and oil content which indicates the involvement of additive gene action, thus feasibility of improvement through simple selection. Seed yield had a positive and significant correlation with seed uptake efficiency, nitrogen harvest index and NUE. First five principal components gave eigenvalues >1.0 and cumulatively expressed 80.67% of the total variation (Table 2). PCA exhibited that plant height, NBP, number of siliquae in the main branch, nitrogen (%) in seed, total nitrogen (%), SNU and seed yield (Kg/ha) were among the most important traits accounting for more than 50% phenotypic variation. Therefore, these quantitative traits should be considered to enhance yield potential as they will be beneficial to develop promising varieties. Accessions such as IC67693, IC277700, IC268336 and RH-30 were identified to be distantly plotted on the dendrogram, thus more diverse in nature. Donors for various traits were also determined based on their pooled performance e.g. IC267693, IC338494, IC571625, IC339605 and IC571654 for seed yield.