Genetic dissection of Fusarium head blight resistance in spring wheat cv. ‘Glenn’

Fusarium head blight (FHB) is a major disease of wheat in many wheat-growing regions affecting wheat yield and quality. Glenn is arguably the most FHB-resistant spring wheat cultivar in the USA. To decipher the genetics of FHB resistance in Glenn, a population of 112 recombinant inbred lines was developed from the cross Glenn × MN00261-4 and evaluated for various FHB related traits at multiple locations in two states (North Dakota and Minnesota) over 3 years. Quantitative trait loci (QTL) analysis detected 15 QTL for FHB resistance related traits and heading date (HD). One QTL for FHB incidence (INC; type I resistance), six QTL for FHB severity (SEV; type II resistance), one QTL for Fusarium damaged kernels (FDK; type IV resistance), four QTL for disease index (DI), and three QTL for HD were detected. Major QTL defined as those consistent across multiple environments and explaining > 10% of the phenotypic variation were detected on chromosomes 5BL, 6BS, and 7AS. They were associated with multiple FHB variables and HD. The stable 6BS QTL with a large effect for FHB SEV resistance corresponded to the Fhb2 gene in Sumai 3. In addition, potentially novel QTL were identified on 1AS, 5BL and 7DS. Our study showed that FHB resistance in the GM population was contributed by loci other than Fhb1 . The major QTL detected for FHB resistance have potential for use in marker-assisted breeding for FHB resistance.