Identification of Superior Combiners for Yield and Component Traits in Bread Wheat using Half-diallel Analysis Across F1 and F2 Generations

Selection of Superior Combiners in Bread Wheat

Abstract

In a diallel cross (excluding reciprocals) involving ten wheat (Triticum aestivum L.) parents, 45 F₁ and 45 F₂ genotypes were evaluated for combining ability in relation to grain yield and associated traits. The analysis of variance revealed significant differences for both general combining ability (GCA) and specific combining ability (SCA). The magnitude of SCA variance exceeded that of GCA, suggesting that non-additive gene action played a predominant role in the inheritance of most traits across both generations. Among the parents, UAS 3011 (F₁-1.409 and F₂-2.154), MACS 6222 (F₁-2.380 and F₂-0.944) and GW 513 F₁-1.722 and F₂-1.415) emerged as strong general combiners for grain yield and its key contributing attributes, making them valuable candidates for hybridization programs aimed at developing superior segregants. Notably, the crosses WR 544 × DBW 187, UAS 3011 × DBW 187, CG 1029 × HI 1544, and MACS 6222 × GW 513 consistently showed favorable SCA effects for grain yield per plant in both generations. The crosses involving good general combiners and showing high SCA effects may be utilized for further breeding purposes and bi-parental mating and diallel selective mating would be useful to exploit both type of gene action (additive and non-additive).