Genotype by Environmental Interaction and Measurements of Stability on Eight Orange-Fleshed Sweet Potato (Ipomoea batatas) Varieties: East Gojjam Zone, North West Ethiopia

Sweet potato is grown for its nature of versatility and adaptability and is a secure food crop in southern parts of Ethiopia. Therefore, this research has been conducted to determine the magnitude of GEI for yield and yield-related traits and to evaluate the adaptability and stability of eight orange-fleshed sweet potato varieties across locations in North West Ethiopia. The experiment was conducted from 2018 to 2019 under rainfed conditions in four districts of East Gojjam Zone (Baso liben, Gozamin, Gonchasiso enesie, and Enbsie Sar mider) using eight OFSP varieties (Kulfo, Kabode, Vitea, Naspot 13, Naspot 12, Nekawango, RW-11, and Mayai). Data were collected on yield and yield-related traits. Genstat statistical software was used to deploy both combined analysis of variance and meta-analysis of the collected data. The combined ANOVA revealed that environment, varieties, and their interaction affect the tested varieties significantly across locations. Debremedhanite was the high-yielding environment (35.9 t/ha), and Kulfo was the best-performing variety (30.67 t/ha) over different environments. Based on the AMMI result, the environment contributes at large (48.49%) to the total variation of variety performance followed by variety (27.18%) and their interaction (24.23%). The testing locations fall in two mega environments that implies that variety recommendation needs to be specific for each mega environment. Hence, Kulfo and Naspot 12 are recommended for Debremedhanit, Arasma, and Degesech based on yield potential and stability of the varieties, and Naspot 13 is recommended for Yelamgej, Eneba, and Getesemani testing locations. This result is useful for breeders and nutritionists who are working on breeding of sweet potatoes and nutrition.