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Filtering by: Subject Brush -- Control -- Oregon Remove constraint Subject: Brush -- Control -- Oregon Degree Field Botany and Plant Pathology Remove constraint Degree Field: Botany and Plant Pathology License All rights reserved Remove constraint License: All rights reserved

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  • Ecology and biological control of an apomictic invasive plant, Chondrilla juncea (Asteraceae)

    Creator:
    Campanella, Donald M.
    Abstract:
    A study consisting of three parts was undertaken to investigate how variation in species interactions, population genetic structure, epidemiological parameters, and plant breeding system may influence the ecology and biological control of an apomictic invasive plant, Chondrilla juncea (Asteraceae). Interactions between natural enemy species may modify their net effect on...
    Resource Type:
    Dissertation
    Full Text:
    . juncea are examined in response to Oregon populations of biological control organisms three decades

  • Overwintering survival of stem rust on perennial ryegrass : construction of a simulation model, and effects of the mycoparasite Sphaerellopisis filum

    Creator:
    Gordon, Tyler C.
    Abstract:
    Stem rust, caused by the fungus Puccinia graminis subsp. graminicola, can cause yield reductions exceeding 90% on perennial ryegrass (Lolium perenne L.) crops grown for seed if not treated with fungicide in the spring. There is evidence that late-spring stem rust epidemics are initiated by populations that survived the winter....
    Resource Type:
    Masters Thesis
    Full Text:
    . filum infected stem rust uredinia in the glasshouse and field under conditions typical of an Oregon

  • The epidemiology of sudden oak death in Oregon forests

    Creator:
    Peterson, Ebba K.
    Abstract:
    The phytopathogen Phytophthora ramorum (Werres, DeCock & Man in't Veld), causal agent of Sudden Oak Death (SOD) of oaks (Quercus spp.) and tanoaks (Notholithocarpus densiflorus syn. Lithocarpus densiflorus), is established in coastal forests of the western United States. Since the discovery of SOD in the Douglas-fir / tanoak forests of...
    Resource Type:
    Dissertation
    Full Text:
    December 5, 2011. Title: The Epidemiology of Sudden Oak Death in Oregon Forests Abstract approved

  • Characterization, epidemiology, and ecology of a virus associated with black raspberry decline

    Creator:
    Halgren, Anne B.
    Abstract:
    The objective of this study was to characterize an unknown agent associated with decline in black raspberry (Rubus occidentalis) in Oregon. A virus was found consistently associated with decline symptoms of black raspberries and was named Black raspberry decline associated virus (BRDaV). Double stranded RNA extraction from BRDaV-infected black raspberry...
    Resource Type:
    Dissertation
    Full Text:
    in black raspberry (Rubus occidentalis) in Oregon. A virus was found consistently associated with

  • Dynamics of Zymoseptoria tritici Fungicide Resistance in the Willamette Valley of Oregon

    Creator:
    Hagerty, Christina H.
    Abstract:
    The development of resistance to multiple fungicide classes is currently limiting disease management options for many pathogens, while the discovery of new fungicide classes has become less frequent. To address this pressing issue, a three-part study with different layers of complexity, objectives, and experimental approaches was conducted using the model...
    Resource Type:
    Dissertation
    Full Text:
    Resistance in the Willamette Valley of Oregon. Abstract approved

  • Mulching to Manage Mummy Berry of Blueberry

    Creator:
    Florence, Jade
    Abstract:
    Monilinia vaccinii-corymbosi pseudosclerotia overwinter on the soil surface and produce apothecia in early spring, providing primary inoculum for Mummy Berry Disease of blueberry. Burial under 2.5 cm of soil or the absence of light have previously been identified as critical factors preventing the development of apothecia. Mulches were applied to...
    Resource Type:
    Dissertation
    Full Text:
    bare ground (or no mulch) control, in combination with application timing, were assessed for their

  • Non-target Effects of Biological Control: Ecological Risk of Tyria jacobaeae (Lepidoptera: Erebidae) to Senecio triangularis (Asteraceae) in Western Oregon

    Creator:
    Rodman, Madison G.
    Abstract:
    Non-target effects are one of the greatest potential risks of weed biological control programs, and understanding non-target effects of biological control at the population level is crucial for predicting when they will occur and altering the perception of biological control as a whole. In this thesis, we assessed the ecological...
    Resource Type:
    Masters Thesis
    Full Text:
    . Title: Non-target Effects of Biological Control: Ecological Risk of Tyria jacobaeae (Lepidoptera

  • Biology of sweet cherry powdery mildew

    Creator:
    Calabro, Jill M.
    Abstract:
    The Pacific Northwest has become one of the nation’s premier sweet cherry, Prunus avium, production areas. As production of sweet cherries has flourished in Oregon and Washington, so has powdery mildew, caused by the fungus Podosphaera clandestina, which infects both foliage and fruit causing severe economic damage to growers. Sweet...
    Resource Type:
    Dissertation
    Full Text:
    , Prunus avium, production areas. As production of sweet cherries has flourished in Oregon and

  • Biology and management of Meloidogyne chitwoodi using oxamyl on potato in the western United States

    Creator:
    David, Nicholas L.
    Abstract:
    Field trials were conducted during 2001 to 2003 to investigate soil population dynamics of Meloidogyne chitwoodi, tuber symptom suppression using oxamyl, and post-harvest tuber symptom development on short-season potato varieties Russet Norkotah and Russet Nugget (San Luis Valley only). The experiments were located in the San Luis Valley in Colorado,...
    Resource Type:
    Dissertation
    Full Text:
    control of nematodes in potato. Report to the Agriculture Research Foundation, Oregon Potato Commission

  • The effects of two fuel reduction treatments on chaparral communities in southwest Oregon

    Creator:
    Sikes, Kendra G.
    Abstract:
    Fuel reduction treatments are being applied to public lands, affecting significant acreage at considerable expense. This study compares the short term effects on a chaparral plant community of two different fuel reduction methods, brush mastication and "hand piling and burning" (HPB). Ceanothus cuneatus dominated the southwestern Oregon study sites where...
    Resource Type:
    Masters Thesis