1a. Objectives (from AD-416):
Identify chemical attractants from wine and vinegar to develop a lure for spotted wing drosophila.
1b. Approach (from AD-416):
Chemical analysis of volatiles of attractive baits, isolation and identification of chemicals that are attractive to the fly, and field testing of chemical combinations in controlled release formulations as a trap lure.
3. Progress Report:
A series of field experiments 1) confirmed the improved trapping of spotted wing drosophila (SWD) flies by combining wine and vinegar, compared to trapping with wine alone or vinegar alone, 2) confirmed the synergy of acetic acid and ethanol as attractants for SWD, and 3) demonstrated the importance of odor compounds from vinegar and wine in addition to acetic acid and ethanol. The odor compounds of a wine and a vinegar were then evaluated using an electroantennal detector (EAD) that determines which compounds the fly is able to detect. All of the compounds that were positive by the EAD were characterized by mass spectroscopy (GC-MS), and their identity confirmed with synthetic chemical standards. These chemicals were then tested using a laboratory assay for attractiveness or deterrence of flies. All of the chemicals from the wine and vinegar that were EAD positive and were not deterrent in the laboratory assay were tested as a blend as a lure in a field trap. This lure comprised of synthetic chemicals was comparable in attractiveness to the original mixture of wine and vinegar. The work reported here addresses objective 3 of the parent project plan.