Genetic Variability, Heritability, and Genetic Advance for Yield and Milling Quality Traits in Rice (Oryza sativa L.) Germplasm

Abstract

Genetic variability is the foundation of effective selection in crop improvement. Fifty rice germplasm lines were evaluated during the kharif season of 2025 at the Regional Agricultural Research Station, Polasa, Jagtial, Telangana, India, using a randomised block design with two replications. Ten yield and milling-quality traits were assessed: days to 50% flowering, plant height, panicle length, productive tillers per plant, grains per panicle, 1000-grain weight, grain yield per plant, hulling percentage, milling percentage, and head rice recovery. Analysis of variance indicated highly significant differences among genotypes for all traits. Phenotypic coefficients of variation exceeded the corresponding genotypic coefficients for every trait, although the differences were generally small for days to 50% flowering, plant height, 1000-grain weight, head rice recovery, and grain yield per plant. High phenotypic and genotypic variability was observed for grains per panicle, head rice recovery, and grain yield per plant. Broad-sense heritability was high for nine traits and moderate for panicle length. High heritability accompanied by high genetic advance as a percentage of the mean was recorded for plant height, productive tillers per plant, grains per panicle, 1000-grain weight, head rice recovery, and grain yield per plant. These estimates identify traits with a favourable expected response to phenotypic selection within the evaluated material. Because the experiment was conducted in one season and one location, the stability of the estimates and the performance of individual germplasm lines should be confirmed through multi-environment evaluation before selections are advanced.