Genetics of Quantitative Traits in Indian Mustard

Analysis of gene effects was done using means of six generations, viz, P₁ P₂, F₁, F₂, BC₁ and BC₂ of a cross, Varuna × YRT-3, of Indian mustard (Brassica juncea) to determine the nature and magnitude of gene actions, governing yield and yield components. Both additive and nonadditive gene actions were important in controlling most of the characters studied. Epistatic effects were predominant over additive and dominance effects with an important role of duplicate type of epistasis for most of the traits. Hybridization systems, such as, multiple or reciprocal recurrent crossing, which exploit both additive and nonadditive gene effects, simultaneously, could be useful in the genetic improvement of the characters studied.