Characterization of Virulence Factors in Spot Form Net Blotch

Spot form net blotch (SFNB) is a significant foliar disease of barley (Hordeum vulgare L.) which is caused by the necrotrophic fungal pathogen Pyrenophora teres f. maculata. To better understand the virulence of P. teres f. maculata, two isolates demonstrating differential levels of virulence were selected to create a mapping population, CAWB05pt4, a highly avirulent isolate and P-A14, a highly virulent isolate, were crossed to generate a population containing 118 progeny. The 118 progeny were phenotyped using popular local barley varieties used across the Upper Great Plains along with both resistant and susceptible checks. Genotyping is conducted utilizing a genotype-by-sequencing (GBS) method developed for Ion Torrent sequencing technology. Genotyping data is used to generate a high density genetic linkage map which we use in conjunction with the phenotypic data to characterize the genetics of SFNB virulence. Preliminary data has been generated and isolates will continue to be screened across the selected barley varieties.