Genetic analysis of grain yield and its associated traits in a set of diverse salt tolerant rice genotypes under coastal salinity condition

Abstract

A set of eight-two diverse salt-tolerant rice genotypes were evaluated under coastal salinity condition for estimating genetic variability, correlation, and PCA in ten quantitative traits. Analysis of variance revealed significant differences among all the genotypes. Among the traits, grains per panicle recorded highest Phenotypic Coefficient of Variation (PCV) and Genotypic Coefficient of  Variation (GCV) values, while days to maturity had the lowest PCV and GCV values. Heritability in broad sense was highest for grain yield followed by panicle length, per cent fertility, days to 50% flowering and days to maturity. High heritability coupled with high genetic advance as percent of mean was observed for grains per panicle, per cent fertility and grain yield. Characters panicle length, grains per panicle, per cent fertility and test weight showed positive and significant correlation with grain yield, whereas days to 50 per cent flowering and days to maturity showed significant and negative correlation with grain yield. Principal Component Analysis (PCA) of ten characters presented 3 principal components with eigen values greater than one, which accounted for 68.44% of the total variation. PCA revealed that five quantitative characters viz., per cent fertility, number of tillers, number of productive tillers, plant height and grain yield significantly influenced the variation in these cultivars. Thus, the present work identified the existence of inherent variability in the salt-tolerant rice genotypes that could be used to exploit the variability directly or through crop improvement programs.