Agronomic and Quality Performance of Winter Wheat Backcross Populations Carrying Non‐Adapted Fusarium Head Blight Resistance QTL

Two BC 3 F 2:5 winter wheat populations carrying Fusarium head blight (FHB) resistance quantitative trait loci (QTL) Fhb1 and Qfhs.ifa‐5A were tested for resistance and agronomic and baking‐quality performance in 10 high yielding environments. The objectives of this study were to determine (i) the resistance effect of the two nonadapted QTL, (ii) their side effects on agronomic and quality performance, and (iii) their relative advantage in European breeding programs. The two populations were split into four QTL classes containing either Fhb1 , Qfhs.ifa‐5A , both QTL or neither of them with about 25 (Opus BC 3 F 2:5 population) and 15 (Anthus BC 3 F 2:5 population) lines each class and check varieties. Disease resistance trials on microplots and yield trials on large plots had two replicates at five locations in Germany in each of 2 yr. Mean FHB ratings (%) between QTL classes carrying either one or two QTL showed significantly ( p < 0.05) improved FHB resistance and a significant variation within QTL classes. Small significant negative effects on grain yield were detected in the Anthus but not in the Opus BC 3 F 2:5 population. However, selection of lines with improved resistance level and similar high yield level like the recurrent parent was feasible. All other differences in agronomic and quality traits were in all cases small although often significant. The introgression of both QTL did not significantly improve the FHB resistance compared to Qfhs.ifa‐5A indicating that this QTL suffices for European breeding programs.