The role of adapted and non-adapted resistance sources in breeding resistance of winter wheat to Fusarium head blight and deoxynivalenol contamination

Abstract

Since resistance is the most important agent in regulating deoxynivalenol (DON), breeding for higher resistance is the key to improve food safety. Fusarium damaged kernels (FDK) show a closer correlation with DON than visual symptoms. This implies a difference in genetic regulation. For this reason, the mapping should be extended not only for the visual symptoms, but also for FDK and DON. Quantitative trait loci influencing only Fusarium head blight (FHB) symptoms, may not be relevant for FDK and DON. Type I and II were pooled to overall resistance at spray inoculation. From 2010 to 2016 three selection platforms were compared by checking running variety breeding programs. The use of exotic sources in breeding significantly increased the number of more resistant genotypes in each selection phase from F3-F8 generations compared to the control program where crosses were not planned for FHB resistance and screening in early generations was also not performed. However, also in this breeding platform – at a lower rate – moderately or highly resistant genotypes could be selected. Of them, eight cultivars were/are in commercial production. The Fusarium breeding program using only adapted and more resistant parents generally gave closer results to exotic breeds, and several highly resistant genotypes were produced as a result. For winter wheat the phenotypic screening at high disease pressure is the key to select highly resistant materials. At low infection pressure the high and medium resistant genotypes come in the same group. The use of more isolates increases the chance to have strong selection pressure each year. FHB resistance was combined with leaf rust, yellow rust, powdery mildew, leaf spot resistance and high protein content (15-18%). The cultivar registration and post registration screening is the key in improving food safety in commercial production.