Theses and Dissertations
Effect of spray droplet size on pronamide control of annual bluegrass (Poa annua L.) and the role of absorption and translocation in the mechanism of pronamide resistance
Mississippi State University
McCurdy, James D.
Tseng, Te-Ming P.
Stewart, Barry R.
Ferguson, Jason C.
Date of Degree
Graduate Thesis - Open Access
Plant and Soil Science with Weed Science concentration
Master of Science (M.S.)
College of Agriculture and Life Sciences
Department of Plant and Soil Sciences
Annual bluegrass (Poa annua L.) is a problematic weed in turfgrass that has evolved resistance to twelve different herbicide sites of action. The mitotic-inhibiting herbicide pronamide has both pre- and post-emergence activity on susceptible annual bluegrass populations. Still, post-emergence activity may be compromised in some resistant populations due to the lack of root uptake or an unknown foliar resistance mechanism. Spray droplet size may affect foliar and soil deposition of pronamide, thus potentially explaining variation in population control or differential foliar and root uptake. Pronamide, flazasulfuron, and pronamide + flazasulfuron deposition were quantified on annual bluegrass as affected by spray-droplet size. The efficacy of these herbicide treatments in resistant (R) and susceptible (S) annual bluegrass populations was then evaluated with two droplet sizes (400 and 1000 μm). Absorption and translocation of pronamide were investigated in R and S populations following foliar-only and soil-only pronamide applications.
Ignes, Martin, "Effect of spray droplet size on pronamide control of annual bluegrass (Poa annua L.) and the role of absorption and translocation in the mechanism of pronamide resistance" (2022). Theses and Dissertations. 5684.