Genotype by Environment Interaction and Grain Yield Stability of Pigeon Pea Genotypes in the Northern Regions of Ghana

Genotype‐by‐environment interaction (GEI) significantly influences crop performance, particularly in breeding programs targeting diverse agroecologies. This study aimed to evaluate genotype stability, agronomic trait interrelationships, and adaptability in test environments. Multienvironment trials involving genotypes of pigeon pea identified stable and high‐yielding genotypes such as L_2015_2, with strong adaptability across environments. The “which‐won‐where” analysis revealed distinct mega‐environments, emphasizing the importance of environment‐specific breeding strategies. Environment Nyan_2022 was the most discriminative and representative, providing optimal conditions for genotype evaluation and selection. Correlation analysis showed significant positive relationships between yield and traits such as seeds per pod and seed weight, highlighting these as key yield determinants. Moderate positive associations between days to 50% flowering, days to maturity, and yield further underscore the role of phenological traits in influencing yield. However, early emergence traits showed negative correlations with yield, indicating potential trade‐offs between early vigor and reproductive success. These findings align with the existing literature and underscore the need for stability‐focused breeding, environment‐specific genotypic deployment, and trait‐based selection indices. The study concludes that integrating GEI analysis with targeted trait improvement and optimized testing environments is pivotal for sustainable crop yield under varying agroecological environments.