Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/6/2007
Publication Date: 6/1/2007
Citation: Vargas, R.I., Leblanc, L., Putoa, R., Eitam, A. 2007. Impact of Introduction of Bactrocera dorsalis (Diptera: Tephritidae) and Classical Biological Control Releases, Fopius arisanus (Hymenoptera: Braconidae), on Economically Important Fruit Flies in French Polynesia. Journal of Economic Entomology. 100: 670-679 Interpretive Summary: Four economically important fruit flies have been introduced accidentally into the Hawaiian Islands. These fruit flies jeopardize development of a diversified tropical fruit and vegetable industry in Hawaii, cause exported fruits to undergo expensive quarantine treatment and provide a reservoir for introduction into the mainland United States. Environmental concerns over the use of malathion bait sprays make it necessary to emphasize alternative methods of control. In the present study conducted a the U.S. Pacific Basin Agricultural Research Center, we examined the attractiveness and feeding propensity of the reduced risk insecticide GF-120 Fruit Fly Bait containing the novel insecticide spinosad for oriental fruit fly and melon fly. These were the first tests ever conducted against Bactrocera species. Results suggest GF-120 Fruit Fly Bait with low contact toxicity, mixed with protein baits offers a reduced risk alternative for control of oriental fruit fly and melon fly, whereby, nontarget effects of broad spectrum contact poisons, such as malathion, could be avoided.
Technical Abstract: Studies were conducted to determine attraction and feeding propensity of oriental fruit fly, Bactrocera dorsalis (Hendel), and melon fly, Bactrocera cucurbitae (Coquillet) to different protein bait mixtures with and without the insecticides spinosad and malathion. The type of protein (GF-120 Fruit Fly Bait, Mazoferm, Nu-Lure Insect Bait, or Provesta autolyzed yeast extract) in the bait had a major influence on B. dorsalis and B. cucurbitae attraction and feeding, which was strongest to fresh Provesta, GF-120, and Mazoferm. Aged baits (4 day-old) were ineffective. In feeding propensity studies, highest response was observed for Mazoferm. On the basis of attraction and feeding responses, Provesta (attraction) and Mazoferm (feeding) outperformed the standard Nu-Lure. A mixture of Provesta and malathion was significantly less attractive to B. dorsalis and B. cucurbitae, compared to a mixture of Provesta and spinosad. Our studies suggest that protein-starved B. dorsalis flies were much more likely to feed on protein compared to protein-fed flies. Spinosad with low contact toxicity, mixed with protein baits offers a reduced risk alternative for control of B. dorsalis and B. cucurbitae, whereby, nontarget effects of broad spectrum contact poisons such as malathion could be avoided.