UC Davis

Stripe rust is a devastating fungal disease that afflicts wheat in many regions of the world. New races of Puccinia striiformis, the pathogen responsible for this disease, have overcome most of the known race-specific resistance genes. We report the map-based cloning of the gene Yr36 (WKS1), which confers resistance to a broad spectrum of stripe rust races at relatively high temperatures (25 degrees to 35 degrees C). This gene includes a kinase and a putative START lipid-binding domain. Five independent mutations and transgenic complementation confirmed that both domains are necessary to confer resistance. Yr36 is present in wild wheat but is absent in modern pasta and bread wheat varieties, and therefore it can now be used to improve resistance to stripe rust in a broad set of varieties.