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Filtering by: Creator MacDonald, M. Remove constraint Creator: MacDonald, M. Academic Affiliation Botany and Plant Pathology Remove constraint Academic Affiliation: Botany and Plant Pathology

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  • Phylogenetics, population genetics, molecular epidemiology, and pathogenicity of the Douglas-fir Swiss needle cast pathogen Phaeocryptopus gaeumannii

    Creator:
    Winton, Loretta M.
    Abstract:
    A hierarchical series of studies, based mainly on molecular data, was conducted to elucidate the life history of the Douglas-fir Swiss needle cast pathogen Phaeocryptopus gaeumannii at macro- and micro-evolutionary scales. This information was then utilized to design and evaluate molecular diagnostic tools for use in studies on the epidemiology...
    Resource Type:
    Dissertation
    Full Text:
    AN ABSTRACT OF THE DISSERTATION OF Loretta M. Winton for the

  • Susceptibility of Pacific yew (Taxus brevifolia Nutt.) to Phytophthora lateralis

    Creator:
    Murray, Marion S.
    Abstract:
    In 1991 Pacific yew (Taxus brevifolia Nutt.) was reported as a new host for Phytophthora lateralis Tucker and Milbrath which is an aggressive root rot pathogen thought previously to be specific to Port-Orford-cedar. This study was designed to compare the pathogenicity of P. lateralis on the two hosts, and to...
    Resource Type:
    Masters Thesis
    Full Text:
    brevifolia Nutt.) to Phytophthora lateralis Abstract Approved: Everett M Hansen In 1991 Pacific yew

  • Insights into the pathology and epidemiology of Phytophthora ramorum, causal agent of sudden oak death

    Creator:
    Daniels, Hazel A.
    Abstract:
    Sudden oak death is caused by the clonally reproducing generalist oomycete Phytophthora ramorum. The pathogen can infect more than 130 different plant hosts including Quercus spp., Larix kaempferi, and Notholithocarpus densiflorus, as well as common nursery genera such as Rhododendron and Camelia, where it causes symptoms ranging from bleeding cankers...
    Resource Type:
    Dissertation
    Full Text:
    : ______________________________________________________ Jared M. LeBoldus Sudden oak death is caused by the clonally reproducing generalist

  • Pathogenesis and intertree transmission of Verticicladiella wageneri in Douglas-fir (Pseudotsuga menziesii)

    Creator:
    Hessburg, Paul F.
    Abstract:
    Verticicladiella wageneri Kendr. is a vascular wilt pathogen of Douglas-fir in the Pacific Northwest, The disease is characterized by black staining of colonized sapwood; crown symptoms are those typical of a wilting syndrome. Histopathological studies revealed that the pathogen is limited to the xylem but causes vascular dysfunction in both...
    Resource Type:
    Dissertation
    Full Text:
    ) Abstract approved: Redacted for Privacy Dr. Lewis F. Roth for Dr. Everett M. Hansen Verticicladiella

  • Resistance mechanisms of Port-Orford-cedar to Phytophthora lateralis

    Creator:
    Oh, Eunsung
    Abstract:
    Breeding Port-Orford-cedar for resistance to Phytophthora lateralis, a causal agent of root disease, begins by screening, through artificial inoculation, phenotypically resistant trees selected from natural stands. The successful program selected tolerant or resistant POC parent trees for the purpose of disease management. Candidate resistant POCs were used in my dissertation...
    Resource Type:
    Dissertation
    Full Text:
    Mechanisms of Port-Orford-Cedar to Phytonhthora lateralis. Abstract approved: M. Hansen Breeding Port

  • Epidemiology and population biology of Inonotus tomentosus as a pathogen of forests of British Columbia

    Creator:
    Lewis, Katherine JoAnn
    Abstract:
    The root disease fungus Inonotus tomentosus, common in the old growth boreal forests of British Columbia, poses a threat to the health of second growth forests established on sites with a previous history of root disease. Colonized stumps occur in groups of 1 to 6; the groups are clumped within...
    Resource Type:
    Dissertation
    Full Text:
    British C9Ilumbia. . A Abstract approved: < Redacted for Privacy Dr. Everett M. Hansen The root disease

  • 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:
    : Everett M. Hansen The phytopathogen Phytophthora ramorum (Werres, DeCock & Man in’t Veld), causal

  • Phytophthora species and riparian alder tree damage in western Oregon

    Creator:
    Sims, Laura L.
    Abstract:
    The genus Phytophthora contains some of the most destructive pathogens of forest trees, including the most destructive pathogen of alder in recent times, Phytophthora alni. Alder trees were reported to be suffering from canopy dieback in riparian ecosystems in western Oregon, which prompted a survey of alder health and monitoring...
    Resource Type:
    Dissertation
    Full Text:
    Tree Damage in Western Oregon Abstract approved: Everett M. Hansen The genus Phytophthora

  • Soil water pressure and Verticillium dahliae interactions on potato

    Creator:
    Gaudreault, Suzanne M.
    Abstract:
    A greenhouse experiment was conducted in 1991 and in 1992 to determine the effect of soil water pressure on potato (cv Russet Burbank) plant growth and infection by Verticillium dahliae. Soil water pressures of -0.01, -0.03, -0.08, or -0.15 MPa were combined factorially with two inoculum concentrations, 0 or 10...
    Resource Type:
    Masters Thesis
    Full Text:
    interactions on potato AN ABSTRACT OF THE THESIS OF Suzanne M. Gaudreault for the degree of Master of

  • Identification and characterization of seven ROP GTPases in Zea mays

    Creator:
    Christensen, Todd M.
    Abstract:
    Regulation of cell division and expansion are critical for plant development. The mechanisms that control these processes are not clearly understood in higher plants. In other eukaryotic models it has been shown that the highly conserved Rho family GTPases play a crucial role in these mechanisms. One distinct subset of...
    Resource Type:
    Masters Thesis
    Full Text:
    AN ABSTRACT OF THE THESIS OF Todd M. Christensen for the degree