Breeding protein-rich pea for semi-arid regions: insights from combining ability and heterosis

Abstract

Abstract Pea (Pisum sativum L.) is a protein-rich legume cultivated in semi-arid regions, where climatic variability constrains productivity. This study assessed combining ability, heterosis, and genetic parameters for yield- and protein-related traits under managed irrigation. Five cultivars (Serge, Boogie, Compana, Jofs, Ultrillo) were crossed in a full diallel, and F₁-F₂ generations were evaluated in Konya, Türkiye. Significant variation occurred for all traits. The F₁ population showed higher SCA effects and heterosis, particularly for grain and protein yield, whereas F₂ exhibited higher GCA effects, Baker ratios, and narrow-sense heritability. Because generations were evaluated in different years, these differences reflect both genetic segregation and contrasting environmental conditions. Jofs × Compana, Ultrillo × Serge, and Serge × Jofs performed consistently well. These superior combinations represent promising breeding materials for improving pea performance under managed irrigation in semi-arid environments, although their stability and breeding value should be validated across multiple environments.