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Wheat production is increasingly threatened by the fungal disease, Fusarium head blight (FHB), caused by Fusarium spp. The introduction of resistant varieties is considered to be an effective measure for containment of this disease. Mapping of FHB-resistance quantitative trait locus (QTL) has promoted marker-assisted breeding for FHB resistance, which has been difficult through traditional breeding due to paucity of resistance genes and quantitative nature of the resistance. The lab of Ma previously cloned Fhb1, which inhibits FHB spread within spikes, and fine mapped Fhb4 and Fhb5, which condition resistance to initial infection of Fusarium spp., from FHB-resistant indigenous line Wangshuibai (WSB). In this study, these three QTLs were simultaneously introduced into five modern Chinese wheat cultivars or lines with different ecological adaptations through marker-assisted backcross in early generations. A total of 14 introgression lines were obtained. All these lines showed significantly improved resistance to the fungal infection and disease spread in 2-year field trials after artificial inoculation. In comparison with the respective recipient lines, the Fhb1, Fhb4, and Fhb5 pyramiding could reduce the disease severity by 95% and did not systematically affect plant height, productive tiller number, kernel number per spike, thousand grain weight, flowering time, and unit yield (without Fusarium inoculation). These results indicated the great value of FHB-resistance QTLs Fhb1, Fhb4, and Fhb5 derived from WSB, and the feasibility and effectiveness of early generation selection for FHB resistance solely based on linked molecular markers.

High molecular weight glutenin subunits (HMW-GS) play a significant role in determining breadmaking qualities of common wheat flour. The study presented in the paper identified two novel HMW-GS (designated as 1Bx14* and 1By15*) at the Glu-B1 locus in Chinese wheat (Triticum aestivum L.) landrace Banjiemang by SDS-PAGE. The open reading frames (ORFs) of the genes were amplified and cloned with designed specific primers. Both of them had sequences highly similar to those of other HMW-GS genes, but displayed minor modification. The ORF of 1Bx14* was 2367 bp long and encoded 789 aa with 4 cysteines, which included 25 nanopeptides, 65 hexapeptides and 7 tripeptides motifs. The ORF of 1By15* was 2106 bp long and encoded 702 aa with 7 cysteines, which included 23 nanopeptides and 53 hexapeptides motifs. The predicted molecular weights of the mature proteins encoded by 1Bx14* and 1By15* genes were 83.1 and 73.2 k Da, respectively. The presence and authenticity of the two genes in Banjiemang were confirmed by bacterial expression and liquid chromatographyelectrospray ionization mass spectrometry (LC-ESI-MS). By phylogenetic analysis, the 1Bx14* was clustered with x-type subunits but had a high divergence with other 1Bx subunits, whereas the 1By15* was clustered with y-type subunits and closely related to subunit 1By15. The study concluded that 1Bx14* and 1By15* from Banjiemang were novel allelic variations of HMW-GS at Glu-B1 locus, which were probably exploitable as new resources for wheat quality improvement.