Genetic Variability and Heritability Studies for Grain Yield and Yield Attributes in Diverse Rice (Oryza Sativa L.) Inbred Lines

An investigation was carried out to know the extent of genetic variability present in the rice inbreds. Totally one hundred and eighty nine genetically diverse inbred lines were considered for the study and analysis of variance found a significant difference for all the traits studied. The range of variation was high for all the traits in the material studied suggesting that there is presence of considerable variability and these traits may be improved by individual plant selection. The coefficient of variationat phenotypic (PCV) and genotypic (GCV) levels were high for spikelets per panicle, grain yield per plant (g) and panicle weight (g). LowPCV and GCV were observed for days to 50% flowering, panicle length (cm), kernel length (mm) and spikelet fertility (%). From the results, high heritability coupled with high genetic advance as a per cent of mean was recorded for grain yield per plant, panicle weight, L: B ratio, test weight and kernel breadth, which indicates the predominance of additive gene effects in controlling these traits and hence simple individual plant selection could be exercised todevelop high yielding genotypes.