We investigated the hypothesis that resistance to deoxynivalenol (DON) is a major resistance factor in the Fusarium head blight (FHB) resistance complex of wheat. Ninety-six double haploid lines from a cross between ‘CM-82036’ and ‘Remus’ were examined. The lines were tested for DON resistance after application of the toxin in the ear, and for resistances to initial infection and spread of FHB after artificial inoculation with Fusarium spp. Toxin application to flowering ears induced typical FHB symptoms. Quantitative trait locus (QTL) analyses detected one locus with a major effect on DON resistance (logarithm of odds = 53.1, R² = 92.6). The DON resistance phenotype was closely associated with an important FHB resistance QTL, Qfhs.ndsu-3BS, which previously was identified as governing resistance to spread of symptoms in the ear. Resistance to the toxin was correlated with resistance to spread of FHB (r = 0.74, P < 0.001). In resistant wheat lines, the applied toxin was converted to DON-3-O-glucoside as the detoxification product. There was a close relation between the DON-3-glucoside/DON ratio and DON resistance in the toxintreated ears (R² = 0.84). We conclude that resistance to DON is important in the FHB resistance complex and hypothesize that Qfhs.ndsu-3BS either encodes a DON-glucosyltransferase or regulates the expression of such an enzyme.

Aegilops tauschii, the diploid wild progenitor of the D subgenome of bread wheat, is a reservoir of genetic diversity for improving bread wheat performance and environmental resilience. Here we sequenced 242 Ae. tauschii accessions and compared them to the wheat D subgenome to characterize genomic diversity. We found that a rare lineage of Ae. tauschii geographically restricted to present-day Georgia contributed to the wheat D subgenome in the independent hybridizations that gave rise to modern bread wheat. Through k-mer-based association mapping, we identified discrete genomic regions with candidate genes for disease and pest resistance and demonstrated their functional transfer into wheat by transgenesis and wide crossing, including the generation of a library of hexaploids incorporating diverse Ae. tauschii genomes. Exploiting the genomic diversity of the Ae. tauschii ancestral diploid genome permits rapid trait discovery and functional genetic validation in a hexaploid background amenable to breeding.

Fusarium head blight is among the most extensively studied fungal diseases of wheat and other small grain cereals due to its impact on yield and quality, but particularly due to its potential to produce mycotoxins, which are harmful to humans and animals. Since our last comprehensive review on QTL mapping and marker‐assisted selection for FHB resistance in wheat in 2009, numerous studies have been conducted to identify, validate or fine‐map resistance QTL. The main aim of this review is to update and summarize findings on FHB resistance breeding of wheat published during the last decade. Furthermore, we compiled a user‐friendly table listing FHB resistance QTL data providing a valuable resource for further FHB resistance research. The role of morphological and phenological traits on FHB resistance and possible consequences for resistance breeding are discussed. This review concentrates current knowledge on breeding for FHB resistance and suggests strategies to enhance resistance by deploying molecular breeding methods, including marker‐assisted and genomic selection.