Genetic variability for micro- and macro-nutrients in Indian mustard [Brassica juncea (L.)] under two environments

Twenty two Indian mustard [Brassica juncea (L.)] genotypes were evaluated in a randomized complete block design with three replications during rabi 2008–2009 under two dates of sowing, viz., November 09 (E1) and November 25 (E2) to assess variability effects of environment on micro (Zn, Cu, Fe, Mn) and macro nutrients (Na, K). The results revealed that genotypes had substantial genetic variability for both micro- and macro-nutrients in seeds. However, the delayed sowing exposed the crop to heat stress especially during seed development appreciably reduced nutrients content. Both genotypic and phenotypic variations were high under delayed sowing (E2) except for Cu and Fe content. Genotypes CS-3000-1-1-1-5, BPR-538-10 and BPR560-6-B exhibited high Mn, Fe and Na content, respectively under both environments, E1 and E2 and would be potential sources for utilization in the breeding programme for enhancing nutritional value of the animal feed. Cu and Fe contents also showed consistently high heritability and genetic advance under both environments, implying that these characters could possibly be controlled by additive gene effects and could be improved by simple selection in segregating generations.