Project Number: 6402-21000-050-00
Project Type: Appropriated

Start Date: Apr 01, 2011
End Date: Mar 31, 2016

Objective:
1: Establish the level of resistance and pattern of cross-resistance/multiple resistance of various weeds to herbicides, and herbicide interactions that promote control of these weeds. 2: Discover potential resistance mechanisms using structural, biochemical and genetic probes. 3: Evaluate the contribution of dispersal mechanisms to the spread and distribution of resistance. 4: Establish structural, biochemical, and genetic characteristics that limit herbicide efficacy against recalcitrant weeds, such as vines (redvine and kudzu) and nutsedges.

Approach:
The approach is holistic, examining not only the mechanism or control of the resistant biotypes, but evaluating the potential for spread of resistance and developing alternative strategies for weed control measures to minimize further development of resistant weeds. Basic growth analyses, assays and bioassays using whole plant and plant tissues will determine major changes that occur in the resistant biotypes in response to herbicide exposure. Studies will involve microscopic approaches (light, fluorescence, standard and scanning and electron microscopy). Subsequent biochemical, genetic, proteomic, immunochemical and radiological techniques will identify more specific sites or differences in herbicide resistant and sensitive weed biotypes within species. This will result in a greater understanding of the biochemistry, physiology and genetics of the mechanisms and spread of resistant weeds, and provide insight on recommendations for better weed control.