Monitoring Insecticide Resistance in Liriomyza trifolii (Diptera: Agromyzidae) with Yellow Sticky Cards

Abstract

The use of commercially available yellow sticky cards coated with thin layers of insecticide-sticker mixtures as a bioassay was explored to determine insecticide resistance in adult Liriomyza trifolii (Burgess). Young flies emerging from celery or chrysanthemum foliage collected in the field were captured on sticky cards treated with various amounts of permethrin or chlorpyrifos. The control included no insecticide. Mortality of the flies was used to estimate the degree of resistance of a given population to these insecticides. Duration of exposure to insecticide before mortality evaluation was standardized at 24 h. Control mortality increased with increasing amounts of sticker on the cards and with increasing adult age. Males were slightly more susceptible to both insecticides than females, and small flies were slightly more susceptible to permethrin than large flies.Dose-mortality estimates produced by the sticky card procedure are comparable with those produced by a topical application bioassay. The sticky card bioassay is a simple procedure that is accurate, repeatable, and usable for field or greenhouse populations.