Assessing the adaptability and stability of new pearl millet hybrids for grain yield, grain iron and zinc content in Ghana using AMMI analysis

Twenty-four pearl millet (Pennisetum glaucum (L) R. Br) single-cross hybrids were evaluated at four environments of northern Ghana during the 2018 and 2019 cropping seasons to estimate the magnitude of genetic variability, heritability and stability for grain yield and related traits and grain micronutrients among the varieties with the view to selecting the most stable hybrids for adoption by farmers. Additive main effects and multiplicative interaction (AMMI) showed significant genotype × environment (G×E) interaction, and stability for the hybrids across the environments with genotypic variance (σ2G) contributing a greater proportion of the phenotypic variance (σ2p) for four traits including grain Fe content and yield. IPCA 1 and IPCA 2 accounted for between 75.95% for downy mildew incidence and 91.28% for grain Zn of the interaction sum of squares for the traits studied. IPCA 1 component accounted for 50.7, 63.2 and 64.1 of the G×E interaction, while IPCA 2 accounted for 30.8, 26.3 and 27.1, respectively, for grain yield, grain Fe and grain Zn content. Moderate to high broad-sense heritability was recorded for most traits, especially grain yield and grain micronutrient, implying that significant trait improvement may be achieved in these traits through recurrent selection. Overall, 3 hybrids viz ICMH IS 16013, ICMH 177023 and ICMH IS 16075 combined high yield with stability, whereas 4 viz ICMH 177023, ICMH IS 16044, ICMH IS 16076 AND ICMH IS 16214 high grain Fe and Zn