An NLR-transposase fusion gene from rye provides broadly effective resistance to stripe rust in wheat

Stripe rust, caused by Puccinia striiformis f. sp. tritici, is a major threat to global wheat production. To explore new resistance resources, we screened 100 hexaploid triticale accessions using the predominant Chinese P. striiformis f. sp. tritici races CYR32, CYR33 and CYR34 and found that most accessions showed high resistance, with the cultivar Rozovskaya displaying near-immunity. Through map-based cloning, we identified a resistance gene located on chromosome 6RL. Analysis of resequencing data from 117 rye accessions revealed two major haplotypes, both of which conferred near-immunity and broadly effective resistance to stripe rust in transgenic wheat. Sequence analysis and virus-induced gene silencing collectively confirmed the identity of this gene as Yr83. Yr83 encodes an atypical nucleotide-binding and leucine-rich repeat protein (NLR) fused to a Harbinger transposase-derived nuclease domain (HTDND). Truncation of the HTDND abolishes resistance, indicating that this domain is essential for Yr83-mediated immune function. Phylogenetic analysis showed that NLR-HTDND proteins are restricted to the Pooideae subfamily. For breeding applications, we employed a small 6RL translocation line that shows excellent agronomic performance, not only conferring strong resistance but also increasing spikelet number and grain number per spike. Our study reveals a transposase-integrated NLR as a valuable resource for wheat stripe rust resistance breeding.