Capturing Males of Pestiferous Fruit Flies (Diptera: Tephritidae): Is the Combination of Triple-Lure Wafers and Insecticidal Strips as Effective as Standard Treatments?

Abstract

The detection of invasive tephritid fruit fly pests relies primarily on traps baited with male-specific lures. Three different male lures are typically used, and accordingly three sets of traps are deployed: those baited with liquid methyl eugenol (ME) or liquid cue lure (CL) for different Bactrocera species and those baited with plug-bearing trimedlure (TML) for Ceratitis species. The liquid lures contain the insecticide naled, whereas the trimedlure plugs contain no toxicant. Preparing the liquid solutions and servicing three types of traps requires consid- erable labor, and handling naled (and possibly ME) introduces potential health risks. The purpose of this study was to compare the effectiveness of Jackson traps baited with a solid dispenser (wafer) containing all three male lures plus a separate insecticidal (DDVP; 2, 2-dichlorovinyl dimethyl phosphate) strip with Jackson traps baited with the standard male lure/toxicant combinations. Trapping was conducted during two 12-week periods in a coffee field on Oahu, Hawaii. The effectiveness of the wafer-baited traps varied among different species. Catch of Bactrocera dorsalis (Hendel) males was similar between wafer-baited and liquid ME-baited traps for both sampling periods. Conversely, traps baited with the standard TML plug captured significantly more Ceratitis capitata (Wiedemann) males than the wafer-baited traps in both sampling periods. The relative effectiveness of the two trap treatments varied between sampling periods for Bactrocera cucurbitae (Coquillett) males. Based on these results, the triple-lure wafer plus separate kill strip does not, at present, appear to be a viable substitute for the male lure/toxicant combinations currently in use.