Seedling resistance of wheat cultivars to Zymoseptoria tritici disease in Ethiopia

Wheat Septoria blotch, caused by the fungus Zymoseptoria tritici blotch (ZTB), is a major and persistent problem for wheat farmers all over the world, including Ethiopia. Before developing management solutions, it is necessary to identify potential sources of resistance. Therefore, the purpose of this study was to see how wheat cultivars react to the ZTB isolates at the seedling growth stage. The 288 treatment combinations were set up in a completely randomized factorial layout in the greenhouse. To identify specific resistance the least significant difference method was utilized. Complete linkage hierarchical clustering method and Euclidean distance were used to classify the cultivars based on the mean pycnidia coverage. The presence of a specific interaction in the pathogen was established by disease severity analysis. Resistance assay detected 124 isolate-specific resistances and 164 no isolate-specific resistance, among all (n = 288) interactions from pycnidia parameter. Danda'a, HONQOLO, Digalu, Dashen, EJERSA, Alemtena, Mosobo, Hitosa, Robe, and Lelisso were conferred as broad-spectrum resistant cultivars at the seedling growth stage. In contrast, wheat cultivars K6295-4A, LEMU, Yerer, Laketch, and ET-13A2 exhibited no isolate-specific resistance and were susceptible to all isolates. Cluster analysis identified two groups based on the similarity of mean pycnidia coverage of wheat cultivars and suggested resistance variability of wheat cultivars. The information is very important for wheat breeders to improve based on the data generated and farmers in Ethiopia will find the information incredibly useful in making informed decisions on how to manage Zymoseptoria tritici disease.