Scrutiny of gene action underlying yield contributing traits and earliness in blackgram (Vigna mungo (L.) Hepper)

Understanding the genetic architecture of complex traits is the major thrust in plant breeding programs. Hence, the present investigation was carried out at a dry land farm of S.V. Agricultural College, Tirupati during rabi, 2020 to elucidate the gene action governing seed yield, yield related traits and earliness in blackgram. The experimental material consisted of six generations viz., P₁, P₂, F₁, F₂, B₁ and B₂ of five blackgram crosses viz., LBG-752 x TBG-104, LBG-752 x PU-31, LBG-752 x TU-40, TU-40 x TBG-104 and IPU-2-43 x TBG-104. The scaling tests suggested that the simple additive-dominance model is inadequate in elucidating gene action in all the crosses for all the traits. Generation mean analysis based on six parameter model made evident that gene interactions varied cross-wise as well as character-wise. A complementary type of epistasis was observed for majority of the yield attributing traits, while days to 50% flowering and days to maturity had duplicate epistasis in majority of the cross combinations. High yielding and short duration blackgram varieties could be developed by exploiting both additive and non-additive gene effects in the present set of breeding material through inter-mating of desirable transgressive segregants in the early generations followed by simple pedigree selection.