Study of Genetic Components for Quality, Yield and Yield Attributing Traits in Rice (Oryza sativa L.)

The choice of selection and breeding procedures for genetic improvement of rice or any other crop largely depends on the type and relative amount of genetic components and presence of non-allelic interaction. In this study, by using generation mean analysis method, six generations (P₁, P₂, F₁, F₂, BC₁ and BC₂) from three crosses of rice, NVSR 303 x IRRI AMT 301, NVSR 303 x GNR 2 and NVSR 303-6 x IRRIAMT 301 were evaluatedfor some quality and agronomic traits including yield and its components and some quality traits. The results showed significant differences among generations for all traits. Most of the additive, dominance, additive x additive, additive x dominance and dominance x dominance effects were significant indicating the importance of the additive, dominance and epistatic modes of gene action in controlling the these characters in rice. The epistatic interaction model was found adequate toexplain the gene action in most of the traits. Only duplicate interaction was recorded for panicle length, protein content, zinc content and crude fiber in all three crosses under study whereas, other traits had more or less influence of both complementary and duplicate epistsis in different crosses. In general, both additive and nonadditive gene action were important for the expression of almost all characters studied therefore, biparental mating followed by selection of desired recombinants from the segregating population is desirable for improvement rice quality along with high grain yield.