Genetic variability, genotypic and phenotypic coefficients of variation, heritability and genetic advance for twenty-one characters in twenty-eight parental lines of hybrid rice were studied. The analysis of variance revealed highly significant differences for all the characters among the genotypes. The magnitude of differences between PCV and GCV was relatively low for all the traits, indicating less environmental influence. The estimates of genotypic and phenotypic coefficients of variation (GCV and PCV) were high for spikelets per panicle, flag leaf area, days to 50 % flowering, days to maturity and grain yield per plant. Heritability and genetic advance were high for all the characters except pollen fertility which had low genetic advance along with high heritability indicating the involvement of additive and non-additive type of gene action respectively in controlling this character. | Studies on variability, heritability and genetic advance in parental lines of hybrid rice (Oryza sativa L.)
