Resistance of European Spring 2-Row Barley Cultivars to Pyrenophora graminea and Detection of Associated Loci

Pyrenophora graminea is the seed-borne pathogen causal agent of barley leaf stripe disease. In this work, we screened a collection of 206 spring two-row barley cultivars from Europe for their resistance to the fungal pathogen. Artificial inoculation with the highly virulent isolate Dg2 revealed a continuous variation for the incidence of infection, with few highly resistant or highly susceptible genotypes. On average, old cultivars showed higher resistance than the more modern ones. Genome-Wide Association Scan was performed by exploiting available molecular data for >4000 SNP markers and revealed a single, highly significant association on the short arm of chromosome 6H, in a genomic position where quantitative trait loci (QTL) for barley resistance to P. graminea were not detected before. Based on the last version of the reference barley genome, genes encoding for proteins with a kinase domain were suggested as candidates for the locus.