Zingerone and the mating success and field attraction of male melon flies (Diptera: Tephritidae)

Abstract

Males of many Dacina (Diptera: Tephritidae: Dacini) fruit fly species are attracted to either methyl eugenol (ME) or cue lure (CL) or its natural analogue raspberry ketone (RK). Recently, the compound zingerone (ZG) has also been shown to attract males of both ME- and CL/RK-responding Bactrocera species, and in the Queensland fruit fly, B. tryoni (Froggatt), males that fed on ZG had a mating advantage over non-fed males. The objective of this study was to determine whether ZG similarly enhanced mating success of CL/RK responding males of the melon fly, Zeugodacus cucurbitae (Coquillett) and to assess the relative attractiveness of CL and ZG to Z. cucurbitae males in the field. ZG was provided in 5 different formulations, including that used in the aforementioned work on B. tryoni. Mating trials were conducted in walk-in field cages containing potted plants, and in all cases 80 ZG-fed (treated) males competed with 80 control (non-fed) males for matings with 80 females. Contrary to B. tryoni, ZG did not confer a mating advantage to Z. cucurbitae males: the numbers of matings procured by treated and control males did not differ significantly for any of the 5 ZG formulations tested. A mark-release-recapture study showed that CL-baited traps significantly more Z. cucurbitae males than ZG-baited traps, which were, however, more attractive than control traps lacking any lure.