Assessment of genetic variability, correlation association in different genotypes of rice (Oryza sativa L.)

Abstract

The present study investigates the genetic variability, heritability, and correlation of yield and yield-attributing traits in 13 rice (Oryza sativa L.) genotypes. Analysis of variance revealed significant differences among genotypes for all 13 traits, including days to 50% flowering, days to maturity, plant height, flag leaf length, flag leaf width, panicle length, number of effective tillers, number of grains per panicle, test weight, spikelet fertility, kernel length, kernel breadth, and yield per plant. The highest genotypic coefficient of variation (GCV) was observed for flag leaf width (55.82%) and yield per plant (53.30%), indicating substantial genetic variability for these traits. Moderate GCV values were recorded for number of effective tillers (28.94%), number of grains per panicle (22.33%), days to 50% flowering (17.07%), plant height (16.41%), test weight (15.07%), panicle length (12.88%), flag leaf length (12.54%), kernel length (11.73%), days to maturity (8.42%), spikelet fertility percentage (8.04%), and kernel breadth (6.07%). The phenotypic coefficient of variation (PCV) was highest for flag leaf width (85.64%) and yield per plant (57.09%), with moderate PCV observed for number of effective tillers (31.86%) and number of grains per panicle (23.23%). Correlation analysis revealed significant positive phenotypic and genotypic correlations between yield per plant and traits such as panicle length, plant height, number of grains per panicle, and days to maturity, suggesting these traits as potential selection criteria for yield improvement. The study underscores the importance of considering both genetic and environmental factors in breeding programs aimed at enhancing rice yield and its components.