Whitefly insecticide resistance research in Georgia

The current research for whitefly insecticide resistance in Georgia includes: 1) toxicological bioassay improvement, 2) LC50 surveys, 3) genetic analysis of resistance mechanisms, 4) relating bioassays to predicted field insecticide efficacy as a tool for insecticide resistance management. We are initially targeting adult response to insecticide, but are in the process of improving bioassays of immatures stages, especially for insecticides that target those stages. So far, adult bioassays easily predicted the efficacy of Venom, Sivanto Prime, and Exirel, but less so with Admire Pro. The adult bioassay mostly missed the efficacy of Oberon, Knack and Beleaf on immatures, as expected. Thus, we are focusing on improved, rapid nymph bioassays that can be run alongside of the adult bioassays. Even with products that affect both adults and nymphs, the bioassays also will have to include a rate response to improve predicted field response.