Over the last several decades, potato production has increased globally as it has been recognized as an important component to improving food security. However, potato production has been continuously challenged by pests. Current pest management practices rely heavily on chemical pesticides. Unfortunately, the overuse of pesticides can be harmful to...
Naked (hull-less) barley has historically been grown for food, but interest in, and breeding efforts for, its use in malting and brewing have increased due to the potential benefits: reduced off-flavors, reduced spent grain, and higher malt extract. These benefits are offset by limiting factors such as high b-glucan and...
Investigation on barley genotype contribution to beer flavor is a relatively new area of research but has interest from members of the malting barley supply chain. This body of work builds upon previous studies by approaching it from new angles that further supports the malting and brewing industries’ interests around...
Hemp (Cannabis sativa L.) is a versatile crop with a wide range of pharmaceutical, commercial, and industrial uses. There is a lack of research and published studies on the ideal storage conditions and their effects on seed quality for hemp. Understanding ideal hemp seed storage conditions would reduce unnecessary seed...
This thesis consists of five chapters: a general introduction, two manuscripts, a collection of published lesson plans, and a general conclusion. The works collected herein are united by the common theme of practical applications in plant breeding. The first manuscript reports a study performed on five malting barley lines grown...
On a global scale, potato (Solanum tuberosum L.) plays an important role in tackling the threat of food insecurity due to its high yield and broad global acceptance. However, pathogens threaten potato production, causing direct yield loss and rendering potatoes tubers unmarketable. Breeding new cultivars that carry multiple resistances is...
One important cool-season perennial grass seed crop grown in Oregon is fine fescue (Festuca rubra L.). Open-field burning has been used for many decades to manage pests, cycle nutrients, and stabilize yield, in fine fescue seed fields, especially as stands age. Legislative restrictions currently limit open-field burning to 6,070 hectares...
Stripe rust (Puccinia striiformis f. sp. tritici) and Septoria tritici blotch (Zymoseptoria tritici) are a constant and significant threat to wheat production, significantly reducing wheat quality and yield. Wheat is responsible for 20% of the world’s human calorie intake, and wheat production must increase to supply the demand of the...
Seed shattering is a constraint to improvement of seed yield in Lolium perenne L. and as a result, seed retention is an essential trait for this valuable crop. Field studies were conducted near Corvallis, OR in two years (2017-2018 and 2018-2019) to identify genetic variation for seed retention and to...
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...
There is a perception that exposing seeds to x-ray in airports during export may affect the quality of seeds. This study was triggered when pear (Pyrus betulifolia) and peach (Prunus persica) grower reported that seeds quality was reduced after they were exposed to X-ray and tested in the final destination....
Olive production potential in Oregon was researched in a multi-disciplinary approach, including a grower survey, a propagation greenhouse study, and a field study, from 2018 through 2020. The Oregon Olive Grower Survey was designed to collect information relating to orchard establishment and management practices, knowledge and understanding of these practices,...
The following thesis consists of four sections: a general introduction, two manuscripts, a general conclusion, and an overall bibliography. The two manuscripts report on: (1) discussing the prospects of developing a perennial malting barley and potential alternative sustainable crop management practices and (2) further exploring the contributions of barley variety...
Hop powdery mildew (Podosphaera macularis) was confirmed in the Pacific Northwest in 1996. Before 2012, the most common race of P. macularis was able to infect plants that possessed powdery mildew resistance based on the R-genes Rb, R3, and R5. Post 2012, two additional races of P. macularis were discovered...
Twenty-three red clover cultivars and accessions were grown in Boyd, KY, and Philomath, OR to evaluate their tolerance of northern anthracnose [NA; Kabatiella caulivora (Kirch.) Karak.] and drought, dry matter (DM) production, and their agro-morphological characteristics. The key research questions of this study were the influence of NA on yield...
Tall fescue is a perennial forage grass widely used in areas not well-suited to perennial ryegrass due to climatic or edaphic stressors including drought and low or high pH. Although tall fescue has many agronomic attributes that make it well suited to a wide range of environments, it is lower...
Wheat (Triticum aestivum L.) is one of the most important crops in the world supplying about 18.8 percent of the world's caloric energy supply and 20 percent of the world's protein. In the Pacific Northwest (PNW), over one million hectares of wheat are grown every year. Wheat production is typically...
The following dissertation consists of six sections: a general introduction, three manuscripts, a general conclusion, and an overall bibliography. The three manuscripts report on: (1) identifying genetic interactions in diverse germplasm developed during introgression of a major gene conferring resistance to stem rust (Puccinia graminis f. sp. tritici), (2) mapping...
Members of the family Sciomyzidae, known as snail-killing or marsh flies, are unique amongst insects in that the vast majority of reared species feed exclusively on mollusks and as a result their biological control potential has been well documented in the scientific literature. However, in North America there is a...
Wheat is a staple food crop with many applications. The composition and quantity of major and minor flour components greatly influence functional dough properties, processing quality, and end-use suitability. Seven to 15% of the weight of wheat flour is protein and the gluten proteins comprise 80-85% of that. The gluten...