Research was conducted in the field and greenhouse to determine if a
kaolinite-based particle film, Surround®, would reduce colonization and early season
feeding damage in cucurbits by the Western Striped Cucumber Beetle, Acalymma
trivitattum (Mannerheim). Greenhouse studies were designed to determine effect of
particle film on cucumber dry weight production...
Fire blight is a serious disease of apple and pear trees caused by the bacterium, Erwinia amylovora. This bacterium harbors a pathogenesis mechanism known as the Hrp secretory operon which induces some resistance genes and suppresses other resistance genes in the host plant following invasion. While previous researchers analyzed expression...
In Oregon’s northern Willamette Valley, cabbage maggot (CM), Delia radicum (L.) (Diptera: Anthomyiidae) often renders Brassica root crops unmarketable. Scheduled insecticides are the only current control. Studies were conducted to: 1) describe and characterize spring emergence of CM flies and their seasonal flight activity relative to degree-day (DD) accumulations; 2)...
A 3-year evaluation of Douglas-fir cones in Montana and Yellowstone National Park, Wyoming, showed the western spruce budworm, Choristoneura occidentalis Freeman, and midges were the most common and injurious insects found each year. Injury was so severe at some plots that no sound seeds could be found.
Quantitative resistance (QR) to disease is usually more durable than qualitative resistance, but its genetic basis is not well understood. We used the barley/barley stripe rust pathosystem as a model for the characterization of the QR phenotype and associated genomic regions. As an intermediate step in the preparation of near-isogenic...
The mountain pine beetle, Dendroctonus ponderosas Hopk., showed a significant advance northward from the 1970 infestation boundary, encompassing almost one-third of the total Park acreage. A fall survey conducted in the Park showed an average of 71.1 trees per acre with red or fading foliage from previous year's attacks and...