TRIMEDLURE - EFFECTS OF STRUCTURAL MODIFICATIONS ON ITS ATTRACTIVENESS TO MEDITERRANEAN FRUIT-FLY MALES (DIPTERA, TEPHRITIDAE)

Sixty-eight structural variants of trimedlure, tert-butyl 4(and 5)-chloro-2-methylcyclohexane-1-carboxylate (TML), the male attractant for the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), were evaluated as attractants to determine the importance of the substituents to the attractiveness of TML. The 1-tert-butyl carboxylate and 4(and 5)-chloro substituents in TML can be replaced selectively with no significant reduction in attractiveness. However, the 2-methyl substituent appears to be very important for high levels of attraction. Thirteen halogen analogs of TML showed initial attractancy that was not significantly different from that of TML. In addition, nine of the halogen analogs were as persistent or more persistent than TML at high levels of attractiveness. In a longer term (15 d) follow-up test with 14 promising lures, no significant difference was found between the attractiveness of four of the lures and a freshly baited TML wick after 4 d, by which time an aged TML wick had become depleted of lure. Of the four lures, trifluoroethyl 4(and 5)-iodo-trans-2-methylcyclohexane-1-carboxylate was especially attractive through 4 d of the test, during which time it was the top-ranked lure. Ethyl 4(and 5)-bromo-trans-2-methylcyclohexane-1-carboxylate were very persistent lures, continuing to catch moderate number of C. capitata through days 11 and 15, respectively.