Effect of physiological state on female melon fly, Bactrocera (Zeugodacus) cucurbitae (Diptera: Tephritidae), attraction to host and food odor in the field

Authors: Vargas, Roger; PINERO, JAIME - Lincoln University Of Missouri; Miller, Neil

Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/19/2018
Publication Date: 6/26/2018
Citation: Vargas, R.I., Pinero, J., Miller, N.W. 2018. Effect of physiological state on female melon fly, Bactrocera (Zeugodacus) cucurbitae (Diptera: Tephritidae), attraction to host and food odor in the field. Journal of Economic Entomology. 111(3):1318-1322.

Interpretive Summary: Foraging behavior of wild female melon fly, a worldwide pest of economically important cucurbit crops, was studied by USDA-ARS and Lincoln University scientists in Hilo, Hawaii in both wild and cultivated habitats on Hawaii Island. For many years based primarily on field cage and laboratory behavioral studies with laboratory reared flies, it was thought that female melon flies with eggs responded primarily to host odors, while those without eggs responded primarily to protein. Results for wild flies obtained in the present study suggest a significant preference for cucumber odor over protein odor irregardless of whether melon flies had eggs or not (gravid or nongravid). Implications of these findings with wild melon flies are discussed with respect to integrated pest management (IPM) control strategies with protein bait sprays, as used in Hawaii. Specifically,the possibility of adding cucurbit volatiles to baits to improve attraction is discussed.

Technical Abstract: Foraging behavior of wild female melon fly, Bactrocera (Zeugodacus) cucurbitae Coquillett, a worldwide pest of economically important cucurbit crops, was examined through mark and recapture studies in both wild (Kona: dominated by the invasive weed ivy gourd, Coccinea grandis [L.]Voigt[Cucurbitaceae]), and cultivated (Kapoho: dominated by papaya, Carica papaya L.[Caricaceae] orchards) habitats on Hawaii Island. Many years of field cage and laboratory behavioral studies with laboratory-reared flies, have indicated that female melon flies with eggs responded primarily to host odors, while those without eggs responded primarily to protein. Kona results indicated that more wild and color-marked F2 females responded to cucumber (Cucumis sativus L.(Cucurbitaceae)) odor than to protein odor with the exception of captured wild flies without eggs which responded similarly to protein bait and cucumber odor. Results with captured wild females and color-marked F2 females in Kapoho suggested a significant preference for cucumber odor over protein odor regardless of whether or not they had eggs in their ovaries with the exception of protein-deprived color-marked F2 females, which responded to both odors in equal numbers. Implications of these new findings based on wild melon flies in natural habitats are discussed with respect to integrated pest management (IPM) control strategies with protein bait sprays as used in Hawaii. The possibility of adding cucurbit volatiles to protein-based baits is discussed.