The T1DL·1VS translocation harboring the Glu-V1/Pm67 loci could accelerate the improvement of disease resistance and quality in wheat

A key objective of wheat (Triticum aestivum) breeding is the simultaneous improvement of disease resistance and bread making quality. The Glu-V1 locus encoding the high-molecular-weight glutenin subunit (HMW-GS) V71 and the powdery mildew resistance gene Pm67 were previously identified on chromosome arm 1VS of the wild wheat species Dasypyrum villosum. Here, we generated the T1DL·1V#4S translocation line NAU195, which carried the V71 subunit for improved bread-making quality but was susceptible to all 18 isolates of the powdery mildew fungus Bgt examined. By contrast, the previously developed T1DL·1V#5S line NAU196 harbors the Pm67 gene conferring broad-spectrum powdery mildew resistance but lacks the V71 subunit. Genetic analysis of F₁ and F₂ progenies from a cross between NAU195 and NAU196 confirmed that Pm67 is a single dominant gene. By screening 2954 F₂ plants, we fine mapped Pm67 to an approximately 2.1 Mb interval on chromosome arm 1VS in the reference genome. We identified 35 high–confidence protein–coding genes in this region, including eight candidate genes encoding nucleotide binding site leucine rich repeat (NLR) proteins. We identified 12 recombinant T1DL·1VS translocation lines harboring both the V71 subunit and Pm67 genes, and introgressed one of the corresponding translocations into the high-yielding cultivar NMZ119. Plant development in the resulting T1DL·1VS translocation lines harboring the V71 subunit and Pm67 genes was comparable to that of NMZ119, with no significant yield penalty but with markedly improved powdery mildew resistance and gluten strength. Overall, our strategy for mapping and pyramiding alien genes in the common wheat background allowed us to generate a valuable genetic resource and molecular tool for accelerating the concurrent improvement of powdery mildew resistance and bread making quality.