Solanum species differ in their degree of frost tolerance and cold acclimation capacity. Cultivated potato species of Solanum tuberosum L. are frost-sensitive, incapable of cold acclimation, and have a maximum freezing tolerance of –3°C. Solanum commersonii Dun is frost-tolerant and can survive to –5ºC pre-acclimation and –10ºC post-acclimation. Breeding attempts...
White mold, caused by Sclerotinia sclerotiorum (Lib.) De Bary, is a destructive yield-limiting disease of common bean (Phaseolus vulgaris L.). Genetic resistance to this pathogen is limited in common bean. Identification of high levels of partial physiological resistance in a genetically cross compatible species, Phaseolus coccineus, is advisable. The objectives...
Hop downy mildew is a devastating disease affecting hop requiring expensive
fungicide applications throughout the growing season. Plant resistance is highly
desirable and theorized as being decidedly quantitative with dominance and epistasis
involved in resistance. An association mapping approach using a mixed-model was
used to identify AFLP markers associated with...
Pollen development is an important process in male flower development, the timing of which may be correlated with time of pollen shed in hazelnut (Corylus avellana L.). Early to very late blooming cultivars were identified and the relationship of microsporogenesis and microgametogenesis, and time of pollen shed were studied in...
Zebrafish, Danio rerio, are widely used as vertebrate research organisms yet little is know about their responses to husbandry stressors. This dissertation examined the whole-body cortisol responses of zebrafish to husbandry stress. Additionally, the effects of stress on the susceptibility to mycobacteriosis and microsporidiosis (Pseudoloma neurophilia) were determined including effects...
Sclerotinia sclerotiorum (Lib.) de Bary is a necrotrophic pathogen capable of causing white mold, a severe disease in common bean. White mold is of particular concern to the Oregon snap bean processing industry, where processors allow less than
3% incidence in harvested shipments. Breeding for white mold resistance in beans...
The relationship between the level of Phaeocryptopus gaeumannii (Rohde) Petrak colonization and severity of Swiss needle cast (SNC) symptoms, the possibility of early testing of Douglas-fir (Pseudotsuga menziesii var. menziesii [Mirb.] Franco) for SNC tolerance, and geographic variation in coastal Oregon with respect to SNC tolerance were investigated. Comparisons between...
This dissertation describes the application and development of molecular tools that have great potential for use in studying variation in strawberry germplasm. The first study evaluated 91 microsatellite (simple sequence repeat, SSR) markers for transferability in 22 Fragaria species and their utility in fingerprinting octoploid strawberries. Out of the transferable...
Kernel hardness (KHA) is a major factor determining break flour yield (BFY) and end-use quality of common wheat (Triticum aestivum L.). Within the soft wheat class, genotypes with consistently softer grains than common soft wheat are considered to be 'extra-soft'. In addition, 'extra-soft' wheats have greater BFY than common soft...
It is often perceived that late maturity of grape gives a more complex aroma
profile to Pinot noir wine, however, there is little understanding of the basic flavor
chemistry of grape maturity on wine aroma. The aroma contributing compounds in
Pinot noir were first identified by aroma extract dilution analysis...