One of the most economically important genes in squash (Cucurbita spp.) is the B gene which conditions precocious depletion of chlorophyll in preanthesis fruit. The B genes are found naturally occurring in at least three of the five domesticated species of Cucurbita, including C. pepo, C. maxima and, most recently...
Phytophthora ramorum is the causal agent of Sudden Oak Death (SOD), which is an economically and environmentally important disease causing up to 80% mortality of tanoaks in Pacific Northwest coastal forests (LeBoldus et al., 2022). There are currently four clonal lineages in the United States and Europe, named North America...
Grasslands in the Pacific Northwest are characterized by seasonally wet, acidic soils that mainly support cool season grasses and a limited number of legume species. A major limitation to efficient animal production in grass-dominant pastures is the decline in the herbage growth rate and nutritional quality of forage from late...
Xanthomonas hortorum pv. carotae (Xhc) is an epiphytic, plant pathogenic bacterium that causes the disease bacterial blight of carrot (Daucus carota subsp. sativus). Infection with Xhc can result in blighting of leaves and umbels and reduce quality and yield of carrot seed crops. Carrot production in the United States approaches...
Timber-concrete composite (TCC) solutions originated in the early twentieth century. There has been a renewed interest in TCC solutions in modern mass timber buildings, especially for floor systems. However due to lack of data, design standards, and code acceptance, TCC solutions require that new mass timber solutions be tested, and...
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...
Orchardgrass (Dactylis glomerata L.) is an important seed crop, but unlike other cool-season perennial grass seed crops such as perennial ryegrass (Lolium perenne L.) and tall fescue [Schedonorus arundinaceus (Schreb.) Dumort.], seed yields have not increased over time so there is considerable room for improvement. Research suggests that plant growth...
Native populations of forest trees are specifically adapted to the climates they inhabit. The farther trees are moved from their local climates (i.e., as the climatic transfer distance increases), the more growth and survival tend to decrease. The transfer limit is the climatic transfer distance beyond which plantation performance is...
Drosophila suzukii (Diptera: Drosophilidae), is a serious pest in soft and stone fruit industries worldwide. The unique serrated ovipositor of female Drosophila suzukii allowed the species to reproduce in intact, ripening fruit before the harvest. Current control methods rely heavily on insecticide application, only becoming less profitable due to the...
This study investigated the effects of diversification strategy through the inclusion of forb and legume based pastures in the feedbase of dairy cows on annual forage production, botanical composition, spring milk yield, N partitioning and methane emissions from dairy cows in Western Oregon. Using a randomized complete block design, 3...