Assessment of Genetic Variability, Heritability and Genetic Advance for Yield and Yield-contributing Traits in Bread Wheat (Triticum aestivum L.)

Abstract

Genetic variability is the foundation of effective selection and crop improvement in wheat breeding programmes. Therefore, the present investigation was conducted during the Rabi season of 2023–24 at the Crop Research Centre, Jigyasa University, Dehradun, Uttarakhand, to evaluate genetic variability, heritability and genetic advance for yield and yield-contributing traits in bread wheat (Triticum aestivum L.). Thirty wheat genotypes were evaluated in a randomized block design with three replications. Observations were recorded for fifteen quantitative characters, including phenological traits, plant height, flag leaf area, productive tillers per plant, spike traits, grains per spike, 1000-grain weight and grain yield per plant. Analysis of variance revealed significant differences among genotypes for plant height, flag leaf area, grains per spike, 1000-grain weight, grain filling period, days to maturity and days to 50% heading, indicating the presence of substantial genetic variability for these traits. The phenotypic coefficient of variation was slightly higher than the corresponding genotypic coefficient of variation for all characters, suggesting a limited influence of environmental factors on trait expression. High heritability estimates were observed for plant height, flag leaf area, grains per spike, 1000-grain weight, spike weight per plant and grain yield per plant. Among these, plant height and flag leaf area also exhibited comparatively higher genetic advance as percent of mean, indicating their potential for effective improvement through selection. The findings suggest that these traits may serve as reliable selection criteria for developing high-yielding bread wheat genotypes under the agro-climatic conditions of the study area.