Yield Performance and Genotype × Environment Interaction of White-Fleshed Sweetpotato Genotypes across Different Agro-Ecologies in Ethiopia

Abstract The white-fleshed sweetpotato (WFSP) remains vital to household food security in Ethiopia, where its adoption is limited by vulnerability to sweetpotato virus disease (SPVD) and low dry matter content (DMC). We assessed 10 WFSP genotypes (nine advanced lines and the standard check ‘Awassa‑83’) across six environments (Halaba, Arbaminch, Werer; 2024 – 2025 main seasons) using a randomised complete block design with three replications. The analysis of variance was computed, and the results detected significant genotypic differences ( p < 0.05) for storage root yield, DMC, and SPVD response. Genotype G2 (Ininda‑1‑20) achieved the highest mean yield (28.1 t/ha), a 32.3% advantage over the check, high DMC (~33%), and low SPVD severity (mean ≈1.5). The notable G × E interaction was observed for all traits recorded, including SPVD, vine length (VL), number of roots per plant (NRPP), above-ground fresh biomass weight (AGFW), storage root yield, and DMC, with variable magnitudes such as SPVD=21.3%, VL=6.7 %, storage root yield=8.9%, NRPP=8.7%, AGFW=3.2%, and DMC=7.6%. This demonstrates that the tested genotypes are sensitive to G × E interaction, warranting further stability analysis. GGE biplots (mean versus stability and the ‘which‑won‑where’ approach) indicated that G2 combined superior performance with acceptable stability across environments. Most genotypes scored less than 3.0 for SPVD, indicating resistance/or tolerance under the test conditions. We recommend on‑farm participatory trials for G2 towards potential release in similar agro‑ecologies. The results highlight the feasibility of selecting WFSP genotypes that simultaneously meet productivity, quality (DMC), and SPVD resistance requirements in Ethiopia’s diverse environments.