Efficacy of 2- and 3-component cone lures for Caribbean fruit fly, Anastrepha suspensa

The Caribbean fruit fly, Anastrepha suspensa Loew (Diptera: Tephritidae), is a quarantine pest of citrus and a production pest of guava and other specialty fruits in Florida. Effective field lures are needed for early pest detection and initiation of control measures. In the spring of 2020, three 10-week field tests were conducted in Homestead, FL to compare efficacy and longevity of 2- and 3-component (2C, 3C) cone lures, the current standards used by regulatory agencies, relative to the traditional liquid protein bait containing torula yeast (TY). Concurrent with field trials, additional lures were field-aged and periodically brought into the laboratory to quantify emissions using newly developed ion chromatography methods. In all field tests, traps baited with TY caught the highest number of flies, and traps baited with 2C lures captured significantly more than traps baited with 3C lures. Field longevity ranged from 6-8 weeks for the 2C lure, and 5-6 weeks for the 3C lure. Analysis of lure emissions is underway to correlate release rates of ammonia, putrescine, and trimethylamine with fly attraction observed in the field. Results indicate that TY still provides the best detection of A. suspensa. Of the two synthetic lures, the 2C cone has a longer field life and is a more effective attractant for Anastrepha, apparently due to a repellent effect of the trimethylamine component in 3C cones.