Feeding and attraction of non-target flies to spinosad-based fruit fly bait.
A spinosad-based fruit fly bait, GF-120, has recently become a primary tool for area-wide suppression or eradication of pest tephritid fruit flies. The present study assessed the attraction and feeding of five non-target fly species to GF-120 in Hawaii. These non-target flies include three beneficial tephritid species [Eutreta xanthochaeta (Aldrich), Tetreuaresta obscuriventris (Loew), Ensina sonchi (L.)] introduced for weed biological control, an endemic Hawaiian tephritid [Trupanea dubautiae (Bryan)] (all Diptera: Tephritidae) and the cosmopolitan Drosophila melanogaster Meigen (Diptera: Drosophilidae). All five non-target fly species were susceptible to GF-120, as was the target pest Mediterranean fruit fly Ceratitis capitata (Wiedemann). Feeding on, or even brief tasting of, GF-120 killed all fly species within 2 h. When individual flies were provided with a choice of GF-120 or honey solution, there was no difference in the frequency of first food encounter by E. xanthochaeta, D. melanogaster or C. capitata. The other three non-target species approached honey more often than GF-120 in their first food encounter. Feeding times on GF-120 and honey were not significantly different for D. melanogaster and C. capitata, while the other four non-target species fed longer on honey than on GF-120. There was no significant difference in feeding time on honey versus GF-120 between males and females of each species. These results suggest that area-wide treatment using GF-120 for the purpose of eradication of pest fruit flies has potential negative impacts on these and other non-target fly species in Hawaii.
Wang
Xin-Geng
XG
Kauai Agricultural Research Centre, University of Hawaii at Manoa, 7370 Kuamoo Road, Kapaa, HI 96746, USA. xingeng@hawaii.edu
Messing
Russell H
RH
D000818:Animals; D004331:Drosophila melanogaster / Q000187:drug effects; D004338:Drug Combinations; D005247:Feeding Behavior; D005260:Female; D006254:Hawaii; D006722:Honey; D007306:Insecticides / Q000633:toxicity*; D008136:Longevity / Q000187:drug effects; D018942:Macrolides / Q000633:toxicity*; D008297:Male; D033621:Tephritidae / Q000187:drug effects* / Q000502:physiology
D004338:Drug Combinations; D007306:Insecticides; D018942:Macrolides; C415329:spinosad