Estimation of Genetic variability and Association Studies for Quantitative Traits in Rice (Oryza sativa L.)

Author: Sumalini K., Shiva Prasad G., Lingaiah N. and Sridhar V.

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Abstract

An experiment was conducted during kharif (July–November), 2021 at ARS, Kampasagar, Telanagana, India to estimate variability, genetic parameters and association among yield and its contributing traits in 270 rice genotypes. ANOVA by REML method showed significant variation among the genotypes for all the traits i.e., days to 50% flowering, plant height (cm), number of effective tillers plant-1, number of tillers plant-1, panicle length (cm) and grain yield (kgha-1). The phenotypic variance was higher than the corresponding genotypic variance for all the traits indicating profound influence of environment in the expression of the traits. The magnitude of difference between phenotypic coefficient of variance (PCV) and genotypic coefficient of variance (GCV) was more for all the traits revealing the environmental effect. GCV was moderate for grain yield and low for the remaining traits and PCV was moderate for plant height, low for days to 50% flowering and high for the remaining traits. Low PCV and GCV values indicate the need for creation of variability through hybridization followed by selection. Moderate heritability coupled with high genetic advance as percent of mean was found for grain yield indicating the preponderance of additive type of gene action in governing the trait and selection may be done in early generations. Heritability was moderate for days to 50% flowering and low for the remaining traits coupled with low genetic advance as percent of mean revealing non-additive gene action in governing these traits hence, direct selection is not effective. Improvement is possible by creating variation and selection. Days to 50% flowering, plant height, number of effective tillers plant-1 and number of tillers plant-1 had positive and highly significant correlation with grain yield indicating selection of these traits can increase grain yield.

Keywords

Rice, GCV, PCV, heritability, genetic advance, correlation

Conclusion

Phenotypic variance was higher than genotypic variance for all the studied traits indicating the profound influence of environment in the phenotypic expression of the traits. Except grain yield, all the traits had low PCV and GCV values indicating narrow genetic base for these traits and variability could be created either through hybridization or induced mutagenesis followed by pedigree selection. Moderate heritability coupled with high genetic advance as percent of mean was found for grain yield indicating the preponderance of additive type of gene action in governing the trait and early generation selection is effective and for the remaining traits recurrent selection could be followed to improve the traits.

References

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How to cite this article

Sumalini K., Shiva Prasad G., Lingaiah N. and Sridhar V. (2023). Estimation of Genetic variability and Association Studies for Quantitative Traits in Rice (Oryza sativa L.). Biological Forum – An International Journal, 15(9): 942-946.