Gene Action for Grain Yield and its Related Traits in Barley (Hordeum Vulgare L.)

Generation mean analysis was carried out on six generations (P₁, P₂, F₁, F₂, B₁ and B₂) in two crosses of barley namely BL2 x RD 2433 and RD 2407 x RD 2433. The data were recorded for days to flowering, awn length, spikelets per spike grain filling period. 1000-grain weight and grain yield per plant. The epistatic interaction was observed for all the seven traits in both crosses. Six parameter model revealed that among the main effects, dominance (h) was more important than the additive (d) effect due to higher magnitude for all the traits. Among the epistatic effects, additive x additive (i) was more important as compared to additive x dominance (j) and dominance x dominance (I) components. Complementary gene action was found in cross BL 2 x RD 2433 for days to flowering and spikelets per spike, whereas duplicate epistasis was observed for other traits where (h) and (I) were found significant. Absolute values indicated that non-fixable gene effects were more important for the inheritance of traits studied. Reciprocal recurrent selection or bi-parental mating between the selected plants in early segregating generation could be helpful for the improvement of these traits.