A five-transgene cassette confers broad-spectrum resistance to a fungal rust pathogen in wheat

Combining fungal-resistance genes into a single cassette enables the generation of highly resistant wheat lines. Breeding wheat with durable resistance to the fungal pathogen Puccinia graminis f. sp. tritici (Pgt), a major threat to cereal production, is challenging due to the rapid evolution of pathogen virulence. Increased durability and broad-spectrum resistance can be achieved by introducing more than one resistance gene, but combining numerous unlinked genes by breeding is laborious. Here we generate polygenic Pgt resistance by introducing a transgene cassette of five resistance genes into bread wheat as a single locus and show that at least four of the five genes are functional. These wheat lines are resistant to aggressive and highly virulent Pgt isolates from around the world and show very high levels of resistance in the field. The simple monogenic inheritance of this multigene locus greatly simplifies its use in breeding. However, a new Pgt isolate with virulence to several genes at this locus suggests gene stacks will need strategic deployment to maintain their effectiveness.

Automated summary

Through the introduction of a transgene cassette containing five resistance genes into bread wheat, researchers have successfully generated wheat lines with highly resistant to aggressive and highly virulent Pgt isolates from around the world. This approach simplifies breeding efforts and enhances resistance levels, although strategic deployment of gene stacks may be needed to maintain effectiveness against new Pgt isolates.