Genetic Variability and Character Association Analysis in Selected Recombinant Inbred Lines of Bread Wheat

Abstract

Wheat (Triticum aestivum L.) improvement relies on the availability of genetic variation and an understanding of the inheritance of yield-related traits. The present investigation assessed genetic variability, genetic advance, heritability and inter-trait relationships in 136 recombinant inbred lines derived from a WH711 × PBW698 cross. The study was conducted during the Rabi season of 2022–23 using an augmented design and data were recorded for eight morphological yield and yield-related traits. For the majority of traits, genotypes differed significantly, indicating the presence of considerable genetic diversity within the population. The phenotypic coefficient of variation (PCV) was higher than the estimated genotypic coefficient of variation (GCV); however, grain yield per plot (g) (25.52%), biological yield per plot (g) (24.01%) and number of tillers per meter (20.74%) exhibited relatively higher GCV, suggesting reduced environmental influence. High heritability accompanied by high genetic advance as a percentage of the mean was recorded for thousand grain weight, number of grains per spike, number of tillers per meter, number of spikelets per spike and biological yield per plot, indicating the predominance of additive genetic effects and greater selection efficiency. Correlation analysis revealed strong and positive associations of number of tillers per meter (0.487), harvest index (0.499) and biological yield per plot (0.932) with grain yield per plot, depicting their potential utility in simultaneous improvement strategies. In conclusion, the studied RILs possess adequate genetic variability for effective selection. Traits expressing high heritability, substantial genetic advance and positive correlations with grain yield may serve as dependable selection indices for yield enhancement in wheat breeding programs.