Final report for project completed with funding from the Oregon State University Agricultural Research Foundation Continuing Researchers Support Program.
Sweet corn and snap bean production, amongst other vegetable crops grown in the Willamette Valley of Oregon, are impacted by soilborne diseases caused by Fusarium species. The decline in sweet corn yields due to Fusarium crown and stalk node rot as well as root rot in snap bean and sweet...
Clubroot, caused by Plasmodiophora brassicae, affects all species of the Crucifer family, including wild mustard. It is a fungus-like microorganism that can persist in soil in the form of durable resting spores for 18 years or longer after an infected crop. These resting spores can be spread through any means...
Sclerotinia sclerotiorum (causal agent of white mold) can cause serious economic losses in snap bean production as well as many other crops. Spores are produced in apothecia (mushroom-like structures) that develop from over-wintering sclerotia in the soil. Sclerotia are long-lived, durable hyphal survival structures produced by the fungus and they...
Sweet corn is susceptible to various pathogenic Fusarium species and has been long known to be subject to early season diseases of seed rot and seedling blight as well as root rot and later season problems with stalk rot and ear rots. More recently, fields in the Willamette Valley of...
The wine grape industry is rapidly growing in Oregon. By the year 2005, we could predict that Oregon will have over 10,000 acres in wine grape production. At a meeting last year, the Grapevine Improvement Committee acknowledged that little was known about the presence of potential pest and beneficial insects...
Objectives 1. Survey Oregon vineyards for the presence, identity and abundance of plant-parasitic nematodes. 2. Relate the distribution and abundance of potentially pathogenic species to viticultural practices and site characteristics. 3. Evaluate the efficacy of Nemacur for reducing populations of plant-parasitic nematodes. 4. Document seasonal changes in the abundance of...
Survey data compiled in 1995 showed that plant-pathogenic nematodes that cause yield loss in California and European vineyards are found in over 85% of Oregon vineyards. In over 37% of the samples collected, population densities of Xiphinema wnericanwn (dagger nematode) and Criconenw1la xenoplax (ring nematode) were greater than levels known...
Objectives: 1. Survey Oregon vineyards for the presence, identity and abundance of plant parasitic nematodes. 2. Document seasonal changes in abundance of species of important plant parasites in order to identify optimum times for sampling. 3. Evaluate the efficacy of Nemacur for reducing populations of plant parasitic nematodes.
Since phylloxera's discovery in a commercial vineyard in August of 1990, nine infestations have been verified in Oregon. With over 95% of Oregon's vineyards planted with ownrooted, Vitis vinifera, non-resistant vines, understanding the insect's biology under our conditions has become important for determining management strategies that minimize rate of spread....
Develop a cost-effective system for identifying potential biological control agents of powdery mildew on grape that are efficacious in the Pacific Northwest. 2. Begin a primary screening program to develop biological control agents specifically adapted to the Pacific Northwest.
To determine if the distribution and frequency of dicarboximide resistance in the Botrytis population in vineyards in western Oregon is rapidly changing or remaining relatively stable. 2. To determine the relationship between fungicide use and the frequency of dicarboximide-resistant strains of Botrytis cinerea in grape, raspberry, snap bean, and strawberry...
Gray mold of grape, caused by Botrytis cinerea, can be a serious problem in Oregon vineyards. Disease control has been achieved primarily through the application of foliar fungicides. For a time, the fungicide benomyl provided outstanding control of this disease; however, by the late-1970's, strains of B. cinerea resistant to...
Objectives 1. Survey Oregon vineyards for the presence, identity and abundance of plant-parasitic nematodes. 2. Relate the distribution and abundance of potentially pathogenic species to viticultural practices and site characteristics. 3. Evaluate the efficacy of Nemacur for reducing populations of plant-parasitic nematodes. 4. Document seasonal changes in the abundance of...
Three forecasting programs for scheduling fungicide applications were selected for comparison with the standard Oregon phenology based program. The California (Gubler-Thomas, UC-Davis) program used leaf wetness and temperature early in the year to predict ascospore infection periods and only temperature during the summer to predict conidial infection periods. The New...
Four year old vines of 18 varieties were cane pruned, trained to a Scott Henry, thinned before veraison, and harvested in October and November 1993. Two of the varieties, Chardonnay and Cabernet Sauvignon, were used as standards. Only four varieties were spur pruned to reduce cropping or cluster size: Dolcetto,...
The immediate objective of this project is to establish a vineyard at the Southern Oregon Experiment Station in which previously untested wine grape cultivars will be evaluated. The ultimate goal is to characterize the production and wine qualitypotential of these cultivars in southern Oregon.
Climatic conditions in southern Oregon are unique among the wine-growing regions of the Pacific Northwest. Previous experience has shown that one strength of this region lies in the production of warm-climate cultivars which may not mature properly in other regions of Oregon. The current selection of such cultivars with known...
Plant-pathogenic nematodes that cause yield loss in California and European vineyards are found in over 85% of Oregon vineyards. Population densities of Xiphinema americanum (dagger nematode) and Criconemella xenoplax (ring nematode) were found in 37% of vineyards at levels reported to cause 10-25% loss in California vineyards. However, these nematode...
To characterize the cultural aspects, maturation, production, and wine quality of several untested Italian, French, and Spanish wine cultivars in southern Oregon.