Genotype by environment interaction analysis for Fusarium head blight response and yield performance of bread wheat (Triticum aestivum L.) in southern Ethiopia

Fusarium head blight (FHB) is one of the major biotic constraints to wheat due to its direct detrimental effects on yield quality and quantity. To manage the disease, the deployment of resistant genotypes is ideal in terms of effectiveness, eco-friendliness, and sustainability of production. The study was conducted to determine the responses of different wheat genotypes to FHB, and to identify suitable and stable wheat genotype(s) regarding the FHB resistance and yield performance. A field study was carried out using eleven bread wheat genotypes in seven locations in southern Ethiopia during the 2019 main cropping season. A randomized complete block design with three-time replicates was applied in this study. The results showed that the lowest mean FHB severity (11.33%) and highest mean yield (4.54 t/ha) were recorded at Bonke. Conversely, the highest mean FHB severity (83.38%) and the lowest mean yield (0.94 t/ha) were observed at North Ari. It was also showed that maximum mean FHB severity (49.25%) and minimum mean yield (2.95 t/ha) were recorded on the genotype Hidase under crosswise assessment. Across locations, a minimum mean FHB severity (17.54, 18.83, and 21.31%) and maximum mean yield (3.92, 3.96, and 3.93 t/ha) were noted from the Shorima, Bondena, and Wane genotypes, respectively. GGE biplot analysis and various comparison tests for FHB severity revealed a higher percentage of variation concerning FHB resistance reactions due to the environment (47% as an interactive element), followed by genotype by environment interaction (21%). AMMI analysis revealed genotype, environment, and genotype by environment interaction had a total variation of 7.10, 58.20, and 17.90% for yield performance, respectively. The inconsistency between genotype responses to FHB and yield performance demonstrated that the environmental component was responsible for significant variability in FHB reaction, yield performance, and the dominance of cross-over interaction. However, the greatest level of resistance to FHB was comparatively found in the genotypes Shorima, Bondena, Wane, and Huluka across locations. Considering both FHB resistance response and yield stability, in most environments, Shorima, Bondena, Wane, and Huluka genotypes were suggested for consideration of cultivation where they are well-performed under the pressure of FHB. North Ari and Hulbareg were acknowledged as more discriminating environments than the others for test genotypes against FHB. Bonke and Chencha were considered ideal environments for selecting superior genotypes with good yield performance.