in the eastern United States have been made for more than 100 years, but the disease eastern filbert blight (EFB), caused by the fungus Anisogramma anomala , has continually hindered such efforts ( Capik and Molnar, 2012 ; Fuller, 1908 ; Johnson
5 years, while older orchards of Barcelona and Ennis are removed when they are heavily diseased and no longer productive. The pathogen Anisogramma anomala causes the disease EFB on susceptible trees of C. avellana . This fungus is endemic to the
causal organism of EFB is Anisogramma anomala , an obligate biotrophic ascomycete that is endemic to eastern North America ( Johnson and Pinkerton, 2002 ). In nature, A. anomala coexists with american hazelnut ( C. americana ), occasionally producing
, 2013 ). Ninety-nine percent of U.S. production comes from the Willamette Valley of Oregon. The lack of commercial hazelnut production in the eastern United States is largely the result of the disease EFB caused by the fungus Anisogramma anomala
in Oregon in 2009 produced ≈37,188 t of hazelnuts on 12,545 ha. In the mid-1980s, EFB, caused by the fungus Anisogramma anomala (Peck) E. Müller, was discovered in Oregon's main hazelnut-producing region. The blight has slowly spread and is now
solely in the Willamette Valley of Oregon, with 99% of U.S. hazelnut crop originating there ( Mehlenbacher and Olsen, 1997 ). The presence of the disease EFB, caused by Anisogramma anomala , has historically prevented the commercial production of
filbert blight, incited by the pyrenomycete Anisogramma anomala , is a serious threat to Oregon’s hazelnut industry. The fungus is native to the eastern United States where it occasionally produces small cankers on the wild american hazelnut. The fungus
from Oregon State University (OSU) have been planted. Eastern filbert blight (EFB), caused by the pathogen Anisogramma anomala , is the most destructive disease of hazelnut in Oregon. The pathogen is endemic to eastern North America, where it
`Gasaway' hazelnut (Corylus avellana L.) is highly resistant to eastern filbert blight caused by Anisogramma anomala (Peck) E. Muller. Progeny produced from controlled crosses of `Gasaway' with five susceptible genotypes and open pollination in a `DuChilly' orchard were planted in a diseased orchard and rated for symptom expression for 9 to 10 years. All progeny were found to segregate 50% resistant: 50% susceptible, indicating that `Gasaway' is heterozygous for a single dominant resistance gene.
Resistant cultivars are a promising disease control method for eastern filbert blight, which is devastating hazelnut production in Oregon. In 1990, two studies were begun to evaluate the relative resistance of European hazelnut (Coyhls avellana) genotypes to the causal fungus, Anisogramma anomala. A randomized block design of 40 genotypes was planted using inoculated trees planted in the borders as the disease source. The first- and second-year disease incidence (percent) were compared to the published disease incidence (percent) based on exposing potted trees of 44 genotypes to high doses of inoculum. Disease incidence was significantly correlated between the two studies in 1991 (r =0.41, P = 0.02) and in 1992 (r =0.64, P = 0.001; rs = 0.35, 0.025 < P < 0.050). Three genotypes, however, showed no disease in the field, but they had disease in >70% of the potted tree study. A plot of disease incidence in the field planting indicates that the inoculum was present throughout the blocks.