The genetic performance of a crop is significantly influenced by its environment, including factors like soil, temperature, disease pressure, drought, and precipitation. Therefore, it is crucial to evaluate genotypes across diverse environments to identify stable varieties that best fit the intended area. In South West and West Shewa zones of Ethiopia, eight nationally released bread wheat varieties were collected from national and regional agricultural research centers and planted in 15 farmers' fields during the 2019 and 2020 crop seasons. The experiment was laid down in Randomized Complete Block Design (RCBD) with three replications. The data was analyzed using SAS 9.4, GEA-R, and GenStat software for analysis of variance, GGE biplot analysis, and principal component analysis. The combined analysis revealed that there are significant variations among genotypes, environments, genotype x environment interactions, and the first two interaction principal component analyses axis. Sanate, Liben, and Wane Varieties showed better yields and greater performance and grain yield stability across years. IPCA 1 and IPCA 2 explained 35.8% and 24.63% of the G x E interactions, respectively. Thus, the diverse environments in which bread wheat varieties were tested exhibited varying responses, highlighting the highly variable nature of these environments. Therefore, those stable varieties can be used by farmers in similar agro-ecologies and environments, demonstrating the importance of understanding the interactions between genotypes and environments in cultivar performance.
Keywords: Variety, GEI, IPCA, Environment, Genetic performance