Combining Ability Analysis for Yield and Its Attributing Traits in Bread Wheat (Triticum aestivum L. em. Thell)

Abstract

Development wheat (Triticum aestivum L.) lines through Lines by Testers crosses, is the foremost objective for enhancing yield importantly for sustainable agriculture. The present investigation was carried out at the Research Farm, Department of Genetics and Plant Breeding, School of Agriculture, Lovely Professional University, Punjab, during the Rabi season of 2023–2025. Thirteen genetically diverse wheat genotypes, including ten lines from NBPGR and three testers from IIWBR, were crossed in a Line x Tester mating design to generate 30 F1 hybrids. These hybrids, along with the parents and a standard check variety, were evaluated to estimate general combining ability (GCA), specific combining ability (SCA) governing yield and its related traits. The experimental material was sown in a randomized block design (RBD) with three replications. Observations were recorded on eleven quantitative characters viz., days to 50% flowering, days to maturity, plant height (cm), number of effective tillers per plant, length of main spike (cm), number of spikelets per main spike, number of grains per main spike, thousand grain weight (g), biological yield per plant, harvest index and grain yield per plant (g). Data were collected from all 30 F1 hybrids, 13 parents and one standard check for each of the traits under study. The analysis of variance revealed highly significant differences among the genotypes, indicating sufficient genetic variability for all the traits studied. GCA analysis identified IC82137 and IC534770 among the lines and SKW–196 among the testers as good general combiners for grain yield and associated traits. SCA effects revealed promising hybrid combinations such as IC534770 x SKW–196 and IC532780 x UNNAT 343, which exhibited high specific combining ability for grain yield per plant. The identified superior parental lines and cross combinations can be effectively utilized in future breeding strategies aimed at enhancing productivity and adaptability in bread wheat.