Efficacy of biological, botanical and chemical insecticides on controlling corn earworm in hemp fields

This is a study conducted over the growing seasons of 2023 and 2024. The efficacy of five insecticides was evaluated to manage caterpillars in hemp in an open field at University of Kentucky Research and Education Center, at Princeton. The evaluated insecticides were Heligen® (Helicoverpa zea nucleopolyhedrovirus, 25.65%), Dipel® DF (Bacillus thuringiensis subsp. kurstaki, 54%), Gemstar® LC (Helicoverpa zea nucleopolyhedrosis virus, 0.64%), Molt-X® (azadirachtin, 3%), and Coragen® (chlorantraniliprole, 18.4%). Each insecticide was applied three and four times, in 2023 and 2024, respectively, with an interval of 6-7 days between each application. Inflorescences of hemp plants were visually inspected, and the numbers of caterpillars were recorded before and after each insecticide application. All insecticides were compared with the control (plots without treatment). All tested insecticides had provided some level of control to corn earworm caterpillars in hemp. Detailed results of control efficacy for each insecticide and hemp yield following the different treatments will be presented and discussed.