The Influence of mixtures of parapheromone lures on trapping of fruit fly in New South Wales, Australia

Tephritid fruit flies of economic importance are monitored using traps containing either cuelure (CL) or methyl eugenol (ME) as an attractant. There would be potential economic advantages if both lures could be combined in a single trap without compromising trapping efficiency. This study presents results from two trials testing combinations of cuelure (4.4 mL) and methyl eugenol (0.5 mL and 2.2 mL) in Lynfield traps near Griffith, NSW and in Sydney. For the Griffith trial, the addition of 2.2 mL of methyl eugenol to the standard cuelure wick quadrupled the overall capture of sterile Queensland fruit fly (Qfly) although significant differences were detected in only one of four trials. Traps were placed between 5 and 55 m from the release point, and distance had no significant effect on the number of flies trapped. Time after trap deployment and all time interactions were significant. The proportion of sterile Qfly trapped within three weeks in the first three releases was >91% of total flies trapped in the CL-ME combinations while the CL only treatment recaptured <83% in the same period. Newman fruit fly were trapped with all treatments but not analysed. In Sydney, the combined lure trapped fewer Qfly, although overall the treatments were not significantly different. There was a seasonal effect with cuelure alone attracting more flies than the combination lure in February and August and less in March and April. The combined lure lowered the capture of fruit fly attracted to methyl eugenol by 88%. Reasons for the discrepancies between the trials are discussed, as well as the potential advantages for surveillance for Qfly and exotic fruit flies. Two additional species attracted to the lure combination are noted.