Field response of Mediterranean fruit flies to ceralure B1 relative to most active isomer and commercial formulation of trimedlure.

In a field test to examine attractancy of Mediterranean fruit fly, Ceratitis capitata (Wiedemann), relative to release rates, equal moles of racemic ceralure B1 and trimedlure isomer C were compared on cotton wicks. Data were collected at 2, 4, and 7 d. The substrates were analyzed for longevity and overall persistence in the field. Ceralure B1 was equally attractive as trimedlure C for the first 2 d and significantly more so at 4 and 7 d based on trap counts of captured male Mediterranean fruit flies. Residue analysis of weathered wicks showed that the trimedlure C lasted for just 2 d in our field evaluations, whereas ceralure B1 had measurable material present after 7 d. Thus, based on the amounts of chemicals released, ceralure B1 was more active even in the first 2 d. Ceralure B1 also was formulated in a plastic matrix (ceralure coin) at three different dosages and tested for attractancy in the field against a 2-g trimedlure plug. A 150-mg ceralure B1 coin was equally attractive as a commercial 2-g trimedlure plug, whereas a 300-mg coin was significantly more attractive during a 6-8-wk deployment. Although our results clearly show that ceralure B1 is a superior attractant to trimedlure, costs of synthesis need to be considered as part of an overall program management strategy.