Generation Mean Analysis for Yield and Its Component Traits in Diallel Population of Cotton (Gossypium hirsutum L.)

Background: The nature and magnitude of gene action decides the choice of breeding procedure for achieving desired genetic improvement in any crop. It is particularly important to have an idea of gene interactions for getting genetic advance for polygenic traits such as yield and fiber traits in cotton. Method: The current study was undertaken to investigate the gene action controlling yield and components traits in eight Gossypium hirsutum varieties by using means of the six generations (P1, P2, F1, F2, BC1 and BC2) of 8 x 8 diallel crossing program. The mean of the crosses for the traits in each generation were used for generation mean analysis. Conclusion: Results revealed that the estimated mean effects (m) were highly significant for all traits, indicating quantitative inheritance of these traits. Out of the seven traits under study five traits showed significance for at least one scaling test. Additive and dominant gene effects were significant for seed cotton yield and number of monopods with larger magnitude of dominance effects than additive ones. Dominance, additive x dominance and dominance x dominance were significant for boll weight, number of monopods, seed cotton yield and seed index. Narrow-sense heritability and genetic advance were found low for most of the traits.