The transfer of a gene conferring resistance to scald (Rhynchosporium secalis) from Hordeum bulbosum into H-vulgare chromosome 4HS

Scald is a serious foliar disease that infects barley (Hordeum vulgare L.) causing reduced yields and adversely affecting quality. A means to combat the disease is to breed cultivars that possess genetic resistance. However, all known resistance alleles have so far originated from within the primary genepool of barley. This reliance on H. vulgare and H. vulgare ssp. spontaneum as resistance sources may encourage virulent forms of the pathogen to become established. To broaden the genetic base of cultivated barley and provide novel resistances to many diseases we have used a species from the secondary genepool of barley, H. bulbosum, in a resistance-breeding programme. In this study we describe the development and trialling of a scald-resistant recombinant line derived from a hybrid between H. vulgare and H. bulbosum. The scald resistance is simply inherited and located on the short arm of barley chromosome 4 (4HS).