Molecular DNA markers have become widely used in all areas of genetic
research. The objectives of this thesis were to develop polymorphic markers in sunflower
and utilize the markers for genetic and candidate gene analyses. Amplified fragment
length polymorphism (AFLP) markers were used to estimate genetic similarities and
assess the...
Although the concept of breeding crops for organic agricultural systems has been around for decades, few studies have been reported for vegetable crops to quantify and compare how conventional and organic systems differ in their selection pressures on genotypes advancing through the breeding cycle; especially research utilizing modern sequencing capabilities....
Durum wheat cultivars for North-Eastern Oregon have to be competitive
in terms of their yield potential with soft white winter wheat cultivars and meet
strict quality requirements of the milling industry. Combining the high yield
potential of fall planted durum wheat cultivars which have an acceptable level of
winter hardiness...
A higher level of efficiency in the production of doubled-haploids must be achieved if
this procedure is to be beneficial in plant improvement. Of equal importance is the
development of protocols, which are not genotypic specific and result in progeny that represent
a random sample of gametes from the parental...
Podosphaera macularis, causal agent of hop powdery mildew, is known to produce cleistothecia (syn. chasmothecia) in eastern North America and Europe, but ascocarps are not reported from the Pacific Northwestern region of North America. Reasons for the apparent absence of cleistothecia in the Pacific Northwest are unknown. We established that...
A micropropagation system was developed for hazelnut cultivars and
rootstocks. Culture establishment was affected by explant source, explant collecting
season, and type of explant. The highest frequency of culture initiation and lowest
tissue oxidation and contamination were obtained from internodes with single axillary
buds from grafted greenhouse-grown plants early in...
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...
In the midst of double-digit growth in market demand for organic products, there is a lag in the growth of certified organic production in the United States. This thesis investigated the motivations and barriers farmers face when making the transition to organic agriculture. Three distinct organic farmer typologies were identified:...
The effects of erect leaf canopies on enhancing grain yield in wheat is not
understood. The main objective of this study was to understand the effect of leaf
angle on grain yield by comparing randomly derived-lines from crosses of erect
and droopy leaf spring wheats. Nine traits associated with canopy...
The success of a plant breeding program depends upon the availability of
useable genetic diversity. Such diversity may be enhanced depending on the type of
hybridization strategy employed. Segregating progenies resulting from F2
populations, a double cross, and a top cross were compared for the amount of
useable genetic diversity...
Meadowfoam (Limnanthes alba Bentham; Order: Brassicales; Family: Limnanthaceae) is a self-compatible, predominantly allogamous, insect pollinated species. Meadowfoam oil is a source of novel unsaturated very-long-chain (VLC) seed oils (C₂₀ and C₂₂) with low concentrations of saturated fatty acids (typically less than 2%) and outstanding oxidative stability. Here we report the...
We isolated and characterized the expression of two genes from Populus
trichocarpa that are homologous to the TERMINAL FLOWER 1 (TFL1) gene from
the model annual plant Arabidopsis. In Arabidopsis, overexpression of the TFL1
gene extends the vegetative growth phase, and the homozygous mutant tfl1 allele
causes early flowering and...
Historically, brewers have used dry-hopping (a cold extraction of nonvolatile and volatile chemicals from hops into fermenting or finished beer) to increase the microbial stability and shelf life of their beer. As hoppy beer styles have gained in popularity over the last decade (2007-2017), the objective of dry-hopping has turned...
Birdsfoot trefoil (Lotus corniculatus L.) is a popular perennial, non-bloating forage legume used for pasture, hay and silage throughout the temperate regions of Europe, Asia Minor, North Africa and North and South America. It is regarded as the most morphologically and biochemically variable species in the genus. Research investigating the...
Marker information in the new oilseed crop, meadowfoam, is limited. Molecular markers to facilitate meadowfoam breeding and cultivar improvement are not available. The knowledge of genetic relationships among recent germplasm is not known. The objectives of this study were (i) to gain an understanding of genetic diversity and relationship patterns...
Spike morphology characteristics and the free-threshing habit of wheat have been extensively investigated because of their evolutionary significance and practical importance. Several genetic systems that govern these traits have been reported. Some studies suggest polygenic inheritance while others have identified major genes. This study was conducted to identify and locate...
Italian ryegrass (Lolium perenne L. spp. multiflorum (Lam.) Husnot) is one of the most troublesome weeds with respect to herbicide resistance selection. Some reasons for this are the numerous documented cases of multiple and cross herbicide resistance and some of the biological characteristics of this species, such as wind cross-pollination...
Strawbreaker foot-rot is a major limiting factor to cost efficient winter wheat
production in the Pacific Northwest. Development of resistant cultivars has been
hindered by the lack of adequate levels of genetic resistance and screening techniques
which can consistently detect desired genotypes.
Studies were conducted to determine if the reported...