FEASIBILITY OF ADULT FEEDING DISRUPTION TESTS (FDT) FOR MONITORING LEPIDOPTERAN RESISTANCE TO CHEMICAL INSECTICIDES.

Lab-strain tobacco budworm (Heliothis virescens) moths were fed different concentrations of spinosyn and permethrin in 10% sucrose to obtain dose-mortality responses. Percent mortality increased with increasing concentration of both insecticides. Ingestion (g of treatment solution per moth) declined with increasing concentration of both insecticides. When trypan blue dye was added to an insecticide solution fed to moths, it provided a dramatic visual marker of disrupted fecal production. These results demonstrate the feasibility of an adult-based feeding disruption test to monitor Lepidoptera for development of resistance to chemical insecticides. [ABSTRACT FROM AUTHOR]