Phytophthora cinnamomi is a soilborne pathogen that causes root rot disease of highbush blueberry (Vaccinium corymbosum L.). When new installations of susceptible blueberry cultivars are infected with P. cinnamomi, plants often fail to grow significant new tissue, greatly reducing yields over the life of the planting. Chemical fungicides are available...
Human actions are pushing natural systems into states that have no historical precedent. In response, empirical and theoretical researchers are increasingly focused on developing ways to predict the responses of ecological systems to change. However, significant knowledge gaps remain, often leading to “ecological surprises” where observed impacts of global change...
Producers in the Willamette Valley of Oregon are interested in growing canola as a rotational crop in grass seed and cereal rotations. Many other Brassicaceae seed crops also are produced within the valley. Concerns of seed persistence and volunteer contamination of Brassicaceae seed crops prompted the investigation of seed persistence...
Seashore paspalum (Paspalum vaginatum Sw.) is an important warm-season perennial turfgrass, known for its tolerance to salinity. Turfgrass is used for homes, municipalities, sod farms, resorts, and sports fields. Seashore paspalum has historically been planted in sub-tropical and tropical climates because of its heat tolerance. Seashore paspalum could become an...
Methods for obtaining accurate, spatially explicit estimates of biomass density in tropical forests are required to reduce uncertainties in the global carbon cycle, and to support international climate agreements and emerging carbon markets. Three-dimensional (3-D) remote sensing techniques sensitive to the vertical structure of vegetation provide a unique opportunity for...
Northern highbush blueberry is a long-lived perennial crop that is well adapted to low soil pH conditions. The plants are often shallow rooted and absorb primarily the ammonium (NH₄) form of nitrogen (N) rather than nitrate-N (NO₃-N). Traditionally, commercial blueberry fields have been irrigated with overhead sprinklers and fertilized using...
Emissions largely associated with the combustion of fossil fuels and agriculture has caused elevated atmospheric deposition of nitrogen (N) and sulfur (S) throughout much of the developed world. Increased atmospheric deposition of N and S can lead to soil and surface water acidification and affect forest soil nutrient supply. The...
The goal of the work in this dissertation was to identify alternative soil amendments to improve plant growth and yield during establishment of highbush blueberry (Vaccinium hybrid). Woody materials, such as sawdust and wood chips, have a high carbon to nitrogen (C:N) ratio and low water holding capacity, which can...
Cervical cancer is the fourth most common cancer in women worldwide with human papillomavirus (HPV) being the main cause of the disease. Currently available treatment methods are limited and emphasize the need for discovery of new therapies that improve patient outcome. Chromosomal amplifications have been identified as a source of...
Algae can be used in a variety of wastewater systems to capture nutrients while fixing carbon dioxide from the atmosphere. I conducted field trials at three locations in Oregon with both corn and potato crops to assess the agronomic value and environmental impact of using the resulting algal biomass as...