stripe rust resistance

Stripe rust was first observed in South Africa in 1996, its spread extended in 1997 and the disease became endemic two years later (1). To date four different pathotypes developed, each with enhanced virulence. In consequence, genes that previously showed resistance were rendered ineffective.

In 1970, Gerechter-Amitai and Stubbs (1) reported that accession G-25 of Triticum dicoccoides Korn was resistant to many races of Puccinia striiformis from different geographical origins. Later, it was shown that this stripe rust resistance was conferred by the dominant gene Yr15 (2,3). McIntosh and Silk showed that it is located on the short arm of chromosome 1B (4). Yr15 was introgressed into tetraploid and hexaploid wheats (2, 5).

Stripe rust is one of the most aggressive diseases on common wheat (Triticum aestivum L. ) and durum wheat (T. turgidum L.var. durum) worldwide. In the United States, the western states are the most affected, although is becoming more important in the central US. Stripe rust is caused by the fungus Puccinia striiformis Westend. f. sp. tritici Eriks. (P. s. tritici).

We acknowledge valuable contributions made by Gina Brown-Guedira during the preparation of this page.

Contributed by Marcelo A. Soria, Wenjun Zhang and Jorge Dubcovsky. KASP marker contributed by Gina Brown-Guedira. We also acknowledge valuable contributions by Harbans Bariana, Manilal William, Beat Keller, Evans Lagudah and Bob McIntosh.

Original version contributed by Colin W. Hiebert

A long chromosomal fragment (25-38 cM) containing three rust resistance genes was translocated between the short arms ofTriticum ventricosum 2NS and the bread wheat chromosome 2AS (1). This segment includes three disease resistance genes: Lr37, Yr17 and Sr38 conferring resistance to leaf rust (Puccinia triticina Eriks), stripe rust (Puccinia striiformis West. f. sp. tritici) and stem rust (Puccinia graminis Pers.