Attraction of Ceratitis capitata (Diptera: Tephritidae) Sterile Males to Essential Oils: The Importance of Linalool.

Small cage and wind tunnel bioassays were used to understand the role of volatile chemicals found in ginger root oil and other essential oils in the attraction of sterile male Mediterranean fruit flies, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). Small cage bioassays found that both a 10 component blend (geraniol, linalool, β-myrcene, limonene, α-pinene, β-pinene, β-caryophyllene, terpinen-4-ol, α-terpineol, and α-humulene) and a 4 component subset of that blend (geraniol, linalool, β-myrcene and limonene) were more attractive than paired mineral oil controls. Both blends were equally attractive as ginger root oil and each other. Deletion studies, which tested all 3 component blends, found decreased attraction when linalool was deleted from the 4 component blend. Linalool alone attracted an equal percentage of flies as the 4 component blend, confirming that this chemical was responsible primarily for attraction to ginger root oil. Wind tunnel bioassays confirmed previous studies that panel traps baited with ginger root oil captured more flies than traps baited with manuka oil. Addition of linalool to manuka oil resulted in capture equal to ginger root oil, and addition of linalool to ginger root oil resulted in capture of more flies than ginger root alone. The results of this study will allow a better understanding of the role of individual plant-based chemicals in the attraction of male C. capitata.