Genetic architecture of quantitative traits in field pea

The nature and magnitude of gene effects for yield and its component traits were studied in field pea using generation mean analysis of the four crosses namely ‘DDR 23’ × “IPFD 1–10’, ‘DDR 23’ × ‘Ambika’, ‘KPMR 400’ × ‘IPFD 1–10’ and ‘IPFD 99–13’ × ‘Ambika’. The P₁, P₂, F₁, F₂, BC₁ and BC₂ generations were studied for eight quantitative traits. Generation mean analysis indicated that dominance and epistatic gene interactions had played major role in the inheritance of all traits. An epistatic digenic model was assumed for all the crosses except in ‘IPFD 99–13’ × ‘Ambika’ cross for seed yield/plant. Additive × additive (i) and dominance × dominance (l) digenic interactions were important as compared to additive × dominance (j) for seed yield and its component traits. Duplicate-type epistasis played a greater role than complementary epistasis. The study revealed the importance of non-additive types of gene action for most of the traits, thereby suggesting that selection at later segregating generations could provide better results.