Genotype X Environment Interaction and Stability of Quinoa (Chenopodium quinoa, Willd.) Genotypes for Yield and Yield-Related Traits in Ethiopia

Agriculture is the pillar of Ethiopia’s economy, employing over 80% of the population. However, it remains highly vulnerable to the impacts of climate change. Promoting climate-smart agricultural practices is therefore critical. Quinoa (Chenopodium quinoa Willd.), a highly nutritious pseudo-cereal with broad adaptability and efficient water use, presents a promising alternative crop for Ethiopia’s diverse agro-ecologies. Its tolerance to drought and salinity makes it an ideal candidate for enhancing food and nutritional security under changing climate conditions. Therefore, this study aimed to evaluate the GEI for seed yield and yield-related traits and identify the stable and high-yielding genotypes of quinoa across six agro-ecological locations in Ethiopia—Negelle Arsi, Haramaya, Holeta, Kulumsa, Melkassa, and Ziway—representing three agro-climatic classifications (lowland, midland and highland). Thirteen genotypes were studied using a randomized complete block design (RCBD) with three replications. The G × E interaction main effect revealed significant GEI effects, particularly for plant height, days to maturity, and grain yield. Among the tested genotypes, ‘Brightest Brilliant Rainbow’, ‘Salcedo-INIA-Puno-Peru’, and ‘Multi-Hued’ demonstrated superior performance across multiple environments. Stability analyses were performed using the AMMI, ASV, and GGE biplot approaches. The analyses revealed significant variation among the genotypes for both adaptability and stability. The AMMI results indicated that environmental effects contributed more to yield variability than genotypic or interaction effects. The AMMI model identified four promising genotypes: ‘Salcedo-INIA-Puno-Peru’, ‘Brightest Brilliant Rainbow’, ‘Multi-Hued’, and ‘Bio-bio’. According to the ASV, the most stable genotypes were ‘Amarilla Sacaca’, ‘Amarilla Maranganí’, ‘Bio-bio’, ‘Cherry Vanilla’, ‘Multi-Hued’, and ‘Brightest Brilliant Rainbow’. The GGE biplot identified ‘Brightest Brilliant Rainbow’ and the Holeta location as the most ideal genotype and testing environment, respectively. ‘Multi-Hued’ and ‘Brightest Brilliant Rainbow’ emerged as the winning genotypes in the only defined mega-environment. Notably, ‘Brightest Brilliant Rainbow’ exhibited a high protein content, ranging from 14.8% at Kulumsa to 17.8% at Melkassa. Overall, ‘Brightest Brilliant Rainbow’ and ‘Salcedo-INIA-Puno-Peru’ were identified as high-performing, stable genotypes suitable for cultivation across diverse Ethiopian environments. These findings confirm quinoa’s adaptability to the broader agro-ecologies of Ethiopia and enable selection of stable, widely adapted varieties through the G × E interaction and stability analyses using AMMI, ASV, and a GGE biplot.