Mayweed chamomile (Anthemis cotula L.) is an annual weed in the Asteraceae family that is commonly found in fields of the Pacific Northwest. Acetolactate synthase (ALS)-inhibiting herbicides are frequently used to control a broad spectrum of weed species including mayweed chamomile. Seeds of four biotypes of mayweed chamomile (KJ, KL1,...
Meadowfoam (Limnanthes alba Hartw. ex Benth) seed meal (MSM), a by-product of meadowfoam oil extraction, has a plant defensive compound known as glucosinolate glucolimnanthin (GLN). Myrosinase enzymes present in soil microbes and meadowfoam seeds can convert GLN to glucosinolate breakdown products (GBPs), which demonstrate herbicidal activity and have the potential...
Italian ryegrass (Lolium perenne spp. multiflorum) is a common weed management problem in turfgrasses, cereals and non-crop areas in the United States. In Oregon, the number of populations with multiple-resistance continues to increase. To manage these resistant populations, the resistance patterns must be determined. In this study, five Italian ryegrass...
Annual ryegrass, or Italian ryegrass (Lolium perenne spp. multiflorum), has been the most stable, in terms of acres, grass produced for the past 25 years in Oregon. Increased interest in Italian ryegrass as a cover crop has increased demand for quality seed. Ideal Italian ryegrass cover crop cultivars are named...
Giant reed (Arundo donax L.) is a candidate to provide feedstock for the Portland General Electric power plant in Boardman, Oregon. Giant reed is a fast perennial grass, producing 23-27 metric tons ha⁻¹ of biomass and has the ability to adapt to diverse environments making it a good candidate for...
Italian ryegrass populations have been identified with evolved resistance to glyphosate in orchards with a history of glyphosate use. Two of these populations were selected to investigate the inheritance of glyphosate resistance. The mechanisms involved in the herbicide resistance were an altered target site for the population SF and reduced...
Roughstalk bluegrass (Poa trivialis L.) (RB) is a weed species that increased very quickly in grass seed production fields of the Willamette Valley. The invasion of RB in grass seed crops often occurs in waterlogged soils. In waterlogged areas, RB exhibited better competitiveness and had greater population densities than other...
Imazamox-resistant wheat (Clearfield®) cultivars carry the Imi1 gene, which confers resistance to the imidazolinone (IMI) herbicide imazamox. Imazamox provides selective control of jointed goatgrass and other weeds in IMI-resistant wheat. Imi1 gene flow between IMI-resistant wheat and jointed goatgrass may occur via hybridization and backcross events. In 2009 and 2010,...