Evaluation of the Rainfastness of Selected Insecticides Against Tarnished Plant Bug

Insect pest management is a critical component of cotton production in the mid-south. Foliar insecticides are an important component of integrated pest management and multiple factors can impact their efficacy.  Little information is available about the impact of rainfall on the efficacy of foliar insecticides. This is an important aspect of pest management given the unpredictable nature of rainfall during the growing season. To determine the impact of rainfall on insecticide performance, studies will be conducted in 2019 and 2020. Plots will be sprayed with one of our ten insecticides of focus and rinsed with water to simulate rainfall. Each plot will be checked for the presence of the targeted pest at 3-6 days and again at 6-12 days. Bioassays will also be conducted in the lab. Leaves will be collected from non Bt cotton and dipped in the selected insecticide and rinsed at different time intervals. Each leaf will be infested with the target pest and mortality will be rated at 48-72 hours. Target pest species will include bollworm, tarnished plant bug, fall armyworm, and thrips, with recommended insecticides.