Thesis
Mechanical weed control in conservation tillage
Washington State University
Master of Science (MS), Washington State University
2007
Handle:
https://hdl.handle.net/2376/103547
Abstract
The Northwest Wheat and Range Region is recognized for dryland production of spring and winter wheat, barley, dry peas, lentils, and chickpeas. Although the climate and soil characteristics enhance crop production, most soils are highly susceptible to wind and water erosion. Conservation tillage (CT) reduces soil loss on cropland by retaining crop residue on the soil surface and minimizing deep tillage. Reduced tillage, however, has resulted in a greater dependence on herbicides for weed control, which increases the risk of developing herbicide resistant weeds, and CT promotes soilborne root-infecting fungal pathogens, such as Rhizoctonia root rot. This research investigated the potential use of a pre-plant rotary harrow in conjunction with a high-residue rotary hoe for in-crop weed control and shallow tillage in a CT system. We hypothesized that the tools would enable mechanical weed control without compromising the benefits associated with CT and would reduced the prevalence of Rhizoctonia root rot. The primary objective was to evaluate a Phoenix1 rotary harrow prototype, pre-plant glyphosate application, and an M&W2 Minimum Tillage rotary hoe on crop density, weed cover, weed biomass at maturity, and crop yield. It was concluded that despite weed reductions, mechanical weed control with the harrow and hoe is less optimal than chemical control because of low efficacy at high weed pressures. The secondary objective was to quantify changes in a population of Rhizoctonia solani in response to soil disturbances near the surface of intact soil cores, but results were not obtained because of low inoculation density.
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Details
- Title
- Mechanical weed control in conservation tillage
- Creators
- Suzanne Kopan
- Contributors
- Stephen S. Jones (Degree Supervisor)
- Awarding Institution
- Washington State University
- Academic Unit
- Crop and Soil Sciences, Department of
- Theses and Dissertations
- Master of Science (MS), Washington State University
- Publisher
- Washington State University; Pullman, Wash. :
- Identifiers
- 99900525002201842
- Language
- English
- Resource Type
- Thesis