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Filtering by: Creator Sneed, S. B. Remove constraint Creator: Sneed, S. B. Academic Affiliation Botany and Plant Pathology Remove constraint Academic Affiliation: Botany and Plant Pathology Resource Type Dissertation Remove constraint Resource Type: Dissertation

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  • Responses of forest understory plants to burial by volcanic tephra from Mount St. Helens, Washington

    Creator:
    Antos, Joseph A.
    Abstract:
    The effects of burial by tephra (volcanic aerial ejecta) on forest understory plants were examined northeast of Mount St. Helens, Washington, in the area where the 18 May 1980 eruption deposited tephra but did not destroy canopy trees. At six sites along a tephra depth gradient from 2-15 cm, understory...
    Resource Type:
    Dissertation
    Full Text:
    Abstract approved: Redacted for Privacy JDonal0 B. Zabel The effects of burial by tephra (volcanic aerial

  • Post-dispersal seed fates in a Western Oregon native prairie

    Creator:
    Clark, Deborah L.
    Abstract:
    Knowledge of post-dispersal seed fates and other regeneration characteristics is crucial for predicting abundances and distributions of populations and, ultimately, community species composition and diversity. Seed fate studies, however, are rare primarily due to the difficulty of determining seed fates and causes of mortality. This thesis investigated post-dispersal seed fates...
    Resource Type:
    Dissertation
    Full Text:
    , Mark V. Wilson, Kenneth B. Johnson, Patricia S. Muir, Donald B. Zobel, and Jeffrey C. Miller, for

  • Diagnosis and Etiology of a Soilborne Disease Complex of Winter Squash (Cucurbita maxima) in the Willamette Valley, OR

    Creator:
    Rivedal, Hannah M.
    Abstract:
    Winter squash (Cucurbita maxima) grown in Oregon’s Willamette Valley for edible seed, frozen foods, and fresh markets is susceptible to an undiagnosed soilborne disease. Diseased squash fields exhibit symptoms of stunting, root and crown rot, vascular discoloration, and late-season wilt, which in extreme cases can lead to total crop failure....
    Resource Type:
    Dissertation
    Full Text:
    : ______________________________________________________ Kenneth B. Johnson Winter squash (Cucurbita maxima) grown in Oregon’s Willamette Valley

  • Genetic variability in the eastern filbert blight pathosystem

    Creator:
    Osterbauer, Nancy K.
    Abstract:
    The heritability of resistance to eastern filbert blight, caused by Anisogramma anomala, in European hazelnut (Corylus avellana) was evaluated in the progeny of seven cultivars crossed in 12 combinations. Progeny produced by crossing 'VR6-28' with three susceptible cultivars segregated 1:1 for complete resistance to eastern filbert blight. Histograms of disease...
    Resource Type:
    Dissertation
    Full Text:
    ., Sunderland, MA. 15. Johnson, K. B., Mehlenbacher, S. A., Stone, J. K., and Pscheidt, J. W. 1996

  • A comparative study of temperate Chamaecyparis forests

    Creator:
    Hawk, Glenn M.
    Abstract:
    The objectives of this study include: (1) analysis of Chamaecyparis lawsoniana, C. taiwanensis, and C. formosensis forests including the structure, composition, and dynamics of plant communities and their environmental relationships; and (2) comparison of the temperate Chamaecyparis forests of Taiwan and the Pacific Northwest with emphasis on structural and successional...
    Resource Type:
    Dissertation
    Full Text:
    . From May to September Figure 5. 060 0 404 CURRENT $ A B SW S+SE MONSOON TAIPHOON C Taiwan

  • Host and Pathogen Genetics in the Sharp Eyespot Disease of Wheat

    Creator:
    Liu, Jiang
    Abstract:
    Wheat sharp eyespot (SES), caused by the soil-borne fungus Rhizoctonia cerealis is a common stem disease of wheat globally. The disease caused a severe and extensive epidemic throughout the Willamette Valley of Oregon in 2014 and has remained one of the most important wheat diseases in this region. However, litte...
    Resource Type:
    Dissertation
    Full Text:
    PCR. Journal of General Plant Pathology 78, 247-54. Gutiérrez-Moya E, Adenso-Díaz B, Lozano S, 2021

  • Synthesis and assembly of Fucus zygote cell walls with an emphasis on alignate and fucans

    Creator:
    Doubet, Scott
    Abstract:
    Fucus distichus L. Powell zygotes were used to investigate cell wall synthesis and development and to construct a model of cell wall structure. Alginate synthesis was investigated. Zygotes were cultured in seawater containing ¹⁴C-bicarbonate. Alginate represented 12%, 37%, and 1.7% of the label recovered from whole zygotes, wall, and cytoplasm,...
    Resource Type:
    Dissertation
    Full Text:
    information. Cellulose. Cellulose is a linear S,1-4-linked D-glucan, the main structural polysaccharide in

  • Localization and time of synthesis of wheat germ agglutinin in developing wheat (Triticum aestivum, L.)

    Creator:
    Triplett, Barbara Ann
    Resource Type:
    Dissertation
    Full Text:
    DEVELOPING WHEAT (TRITICUM AESTIVUM, L.) Abstract approved Redacted for Privacy Ralk S. Quatrano The

  • Understory herb and shrub responses to root trenching, pre-commercial thinning, and canopy closure in Douglas-fir forest of the western Cascades, Oregon

    Creator:
    Lindh, Briana C.
    Abstract:
    This thesis examines factors limiting understory herb presence and flowering in young second-growth Douglas-fir (Pseudotsuga menziesii) forests on the west side of the Cascade Mountains, Oregon, USA. I studied the belowground effects of canopy trees on understory herbs and shrubs in old-growth forests using trenched plots from which tree roots...
    Resource Type:
    Dissertation
    Full Text:
    Forests of the Western Cascades, Oregon. Abstract approved: Patricia S. Muir This thesis examines

  • The effects of abscisic acid on gene expression during wheat germination

    Creator:
    Ballo, Barbara
    Abstract:
    Germination of immature (Stage III) and mature (Stage V) wheat (Triticum aestivum L. var. Chinese Spring and Yamhill) embryos is prevented by the inclusion of 10⁻⁴ M abscisic acid (ABA) in culture medium. In addition, Stage III embryos develop into mature embryos in culture medium containing ABA. In the absence...
    Resource Type:
    Dissertation
    Full Text:
    Gene Expression During Wheat Germination Redacted for privacy Abstract approved: Ralph S. buatrano