Study of variability parameters of rice under high temperature tolerance conditions

Abstract

Forty six rice varieties were evaluated at IGKV, Raipur under heat stress condition. Analysis of variance revealed presence of high variability among the genotypes forall the traits. The analysis of variance showed that the mean sum of squares due to replication were significant for plant height, panicle length, leaf length, filled grain panicle-1, spikelet fertility percentage, spikelet sterility percentage. The results showed that PCV (Phenotypic Coefficient of Variation) in general was higher than GCV (Genotypic Coefficient of Variation) for maximum of the characters. The highest phenotypic and genotypic coefficient of variation was found for number of unfilled grains per panicle (56.73%, 54.53%) followed by total number of grain per panicle (35.33%, 34.25%). High heritability was found for days to 50% flowering (0.990) followed by leaf length (0.967) and yield/plant (0.941). High genetic advance was obtained for total number of grains/panicle (107.08) followed by number of filled grains/panicle (73.69). Those characters which have high PCV and GCV have high heritability and genetic advance and can be considered for direct selection.