|NEUPANE, ANJAN - North Dakota State University|
|TAMANG, PRABIN - North Dakota State University|
|BRUEGGEMAN, ROBERT - North Dakota State University|
Submitted to: Phytopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/12/2014
Publication Date: 4/15/2015
Publication URL: http://handle.nal.usda.gov/10113/60742
Citation: Neupane, A., Tamang, P., Brueggeman, R.S., Friesen, T.L. 2015. Evaluation of a barley core collection for spot form net blotch reaction reveals distinct genotype-specific pathogen virulence and host susceptibility. Phytopathology. 105(4):509-517.
Interpretive Summary: Spot form net blotch (SFNB) is a major foliar disease of barley worldwide. SFNB epidemics have recently been observed in major barley producing countries including major barley producing regions of the United States. Local barley cultivars harbor little resistant to the current pathotypes that occur in the United States due to recent shifts in virulence of the local pathogen populations. Here we identify sources of resistance effective against four diverse isolates of P. teres f. maculata, the causal agent of spot form net blotch. A total of 2062 world barley core collection accessions were evaluated for resistance to isolates of the pathogen collected in the United States, Australia, New Zealand, and Denmark. Collectively, only 15 barley accessions were resistant across all isolates tested. These resistant accessions will be used in germplasm development to integrate the resistance into locally adapted varieties.
Technical Abstract: Spot form net blotch (SFNB) caused by Pyrenophora teres Drechs. f. maculata Smedeg., (anamorph Drechslera teres [Sacc.] Shoem.) is a major foliar disease of barley (Hordeum vulgare L.) worldwide. SFNB epidemics have recently been observed in major barley producing countries, suggesting that the local barley cultivars are not resistant and that virulence of the local pathogen populations may have changed. Here we attempt to identify sources of resistance effective against four diverse isolates of P. teres f. maculata collected from around the world. A total of 2062 world barley core collection accessions were phenotyped using isolates of the pathogen collected in the United States (FGO), Australia (SG1), New Zealand (NZKF2), and Denmark (DEN 2.6). Isolate-specific susceptibility was identified in several of the barley accessions tested, indicating variability in both pathogen virulence and host resistance/susceptibility. Collectively, only 15 barley accessions were resistant across all isolates tested. These resistant accessions will be used to generate mapping populations and for germplasm development. Future research will involve the characterization of host resistance, pathogen virulence, and the host-pathogen interaction associated with SFNB of barley.