Chlorpyrifos ethyl-oxon sensitive and insensitive acetylcholinesterase variants of greenhouse whitefly Trialeurodes vaporariorum (Westw.) (Hemiptera:Aleyrodidae) from Turkey

Resistance to the organophosphate chlorpyrifos ethyl was investigated in greenhouse populations of Trialeurodes vaporariorum from Turkey using both bioassay and biochemical studies. These populations were collected from Antalya, Izmir, and Mersin. LC50 values to chlorpyrifos ethyl were determined for all populations using leaf dip bioassay. Resistance ratios (RRs) were calculated from these LC50 values relative to the susceptible BCP population. Bioassay results from all populations revealed varying levels of resistance to chlorpyrifos ethyl with resistance ratios between 7.16- and 12.89-fold in the greenhouse whitefly populations from Turkey. Results revealed the first documented cases of insecticide resistance in this species in Turkey.