Oomycete and fungal pathogens threaten food, fiber, and forests around the world. With climate change, these pathogens are expected to emerge more frequently. Evolution can facilitate their emergence through mechanisms such as mutations that change or expand host range. Characterizing evolutionary mechanisms in plant pathogens will contribute to our ability...
The climate of the Pacific Northwest is in flux, and existing forest ecosystems are stressed and poised to shift in fundamental ways, with or without human intervention. This dissertation probes the nature of forest responses to environmental change through investigations of morphology and genetics of three species of alder co-occurring...
Lilacs are a group of ornamental trees and shrubs in the Oleaceae family consisting of 22 to 30 species. There are six series within genus Syringa: Pubescentes, Villosae, Ligustrae, Ligustrina, Pinnatifoliae, and Syringa. Fertility and cross-compatibility among cultivars, species, and series have yet to be formally investigated. Over three years,...
Irrigated agriculture constitutes the greatest consumptive water use globally, so that irrigation efficiency measures are an important part of global efforts to best utilize this limited resource. However, greater irrigation efficiency must be achieved while simultaneously maintaining or increasing crop yields and farming profitability. Incremental water use decisions are made...
While there is a persistent inverse relationship between latitude and species diversity across many taxa and ecosystems, deviations from this norm offer an opportunity to understand the conditions that contribute to large-scale diversity patterns. Marine systems, in particular, provide such an opportunity, as marine diversity does not always follow a...
A review of research conducted at OSU to determine compost value as a mulch or soil amendment for blueberry produced under conventional, transitional, or organic production systems.
The process of plant speciation often involves the evolution of divergent ecotypes in
response to differences in soil water availability between habitats. While the same set of traits
is frequently associated with xeric/mesic ecotype divergence, it is unknown whether those
traits evolve independently or if they evolve in tandem as...
The cultivated strawberry, Fragaria Xananassa, is one of the youngest domesticated plants. Its 18th century origin via hybridization in Europe between the North American F. virginiana and the South American F. chiloensis was documented by the botanist Antoine Nicolas Duchesne. His 1766 “Natural History of Strawberries” is an extraordinary work...