tert-pentyl 4 (and 5)-chloro-trans-2-methylcyclohexanecarboxylate, a highly effective and persistent male specific attractant for the Mediterranean fruit fly (Diptera : Tephritidae)

The attraction of male Ceratitis capitata (Wiedemann) to tert-pentyl 4 (and 5)-chlorotrans-2-methylcyclohexanecarboxylate (or pentamedlure) was compar ed to its attraction to trimedlure to establish the suitability of pentamed lure as a possible alternate for trimedlure in applications that use a cott on dental-roll wick dispenser. Results from field tests with released steri le C. capitata showed that pentamedlure, applied to cotton dental roll wick s, was not only comparable to trimedlure in attractiveness but was more per sistent. Batch to batch variations in isomer distribution of pentamedlure a ppeared to have little effect on attraction. Dose-response data showed that pentamedlure, applied at 0.02 and 0.16 ml/wick, initially caught more flie s than trimedlure at comparable doses. Moreover, initial catches for pentam edlure for most dosages tested exceeded, but not significantly, initial cat ches for trimedlure despite a much higher load (2 ml/wick). Trimedlure init ial catches within a natural population of wild C. capitata were significan tly higher than pentamedlure catches at a comparable dosage (0.2 ml lure/wi ck). However, pentamedlure-treated wicks were 2 to 3 times more persistent than wicks treated with trimedlure.