Cloning of the broad-spectrum wheat leaf rust resistance gene Lr47 introgressed from Aegilops speltoides

Abstract Leaf rust, caused by Puccinia triticina Eriksson ( Pt ), is one of the most severe foliar diseases of wheat. Breeding for leaf rust resistance is a practical and sustainable method to control this devastating disease. Here, we report the identification of Lr47 , a broad-spectrum leaf rust resistance gene introgressed into wheat from Aegilops speltoides . The Lr47 gene encodes a coiled-coil nucleotide-binding leucine-rich repeat protein that is both necessary and sufficient to confer Pt resistance, as demonstrated by loss-of-function mutations and transgenic complementation. New Lr47 introgression lines with no or reduced linkage dragwere generated using the ph1b mutation, and a diagnostic molecular marker for Lr47 was developed. The CC domain of the Lr47 protein was not able to induce cell death, nor did it have self-protein interaction. The cloning of Lr47 expands the number of Pt -resistance genes that can be incorporated into multigene transgenic cassettes to control this devastating disease.