Location: Temperate Tree Fruit and Vegetable Research
Project Number: 2092-22430-003-038-I
Project Type: Interagency Reimbursable Agreement
Start Date: May 1, 2021
End Date: Apr 30, 2023
Objective:
Our first research goal will be to collect, isolate and identify biologically active compounds (pheromones and/or food attractants) that are specific to the different adult life stages of Asian Giant Hornet (AGH). This will be done in
collaboration with WSDA, ARS, and academic Japanese scientists. Our second research goal will be to test potential AGH attractants in the field and incorporate them into commercial trap designs. For this project, identification of potential female produced pheromone components will be done using gas
chromatography-mass spectrometry (GC-MS) and coupled gas chromatography-electroantennogram detection (GC-EAD). Identified chemicals will then be tested behaviorally in Y tube olfactometer and wind tunnel assays. Compounds of interest will then be tested in the field to establish their efficacy.
Formulations and dispensers for attractant semiochemicals will be developed and tested in collaboration with private industry partners who can manufacture lures and traps for purchase. Results from this agreement will provide PPQ with new information that will allow them to make informed decisions in support of trapping and control strategies of Asian Giant Hornet.
Approach:
Several queen and worker Asian Giant Hornet (AGH) will be captured in Japan or Washington State by collaborators and immediately frozen until needed. Consistent frozen and/or live insect material will be shipped to the U.S. if needed (under APHIS PPQ permit). The insect body surface will be washed in with solvent at room temperature (RT) for 1 minute. Extracts will be concentrated down and shipped to the ARS lab for GC-MS analysis. Samples will be processed and set up for GC-MS analyses. Identification of major components will be based on comparison of GC retention time and mass spectra of authentic standards as well as a chemical library. Frozen Queen adults will be dissected for preparation of samples for chemical analyses. Venom sacs will be collected and submerged in small amounts of solvent. Samples will then be directly injected into a GC-MS for analysis. Solid phase microextraction (SPME) can also be used to collect volatiles from venom glands if needed. Gland-produced compounds will be identified by comparison of their mass spectra with those reported in electronic libraries (NIST) and by checking their mass spectra and retention times against those of synthetic standards. The insect body surfaces will be washed in at room temperature (RT) for 1 minute. Extracts will be concentrated down and analyzed via GC-MS. Worker body wash extracts will be compared to queen body wash extracts to examine differences in their chemical composition. Frozen Worker adults will be dissected in the same way as Queens. Venom gland extracts will be prepared and analyzed as described for Queen samples. Venom gland extracts of both Queen and Worker AGH will be examined for chemical differences. We will then compare our aggregation pheromone identification results with previously published work. GC-electroantennogram detection (EAD) will be used to measure the electrophysiological olfactory responses of hornet antennae to volatile, sting venom compounds, collected by Solid Phase Microextraction (SPME) or solvent extraction. Antennal preparations will follow similar methods to those previously done on single, tip cut hornet antennae. Compounds that elicit an antennal response will then be identified via GC-MS analysis. Traps baited with lures will be tested in Washington state and Japan. ARS employees will require overnight travel for trap assays conducted in Washington due to 250 mile distance from AGH sightings to ARS station. Traps will be checked weekly and lures to be refreshed as needed. Lures to be made from commercially available or synthetic chemicals by APHIS/ARS labs and used for lab and field assays.
