Location: Invasive Plant Research Laboratory
Project Number: 6032-22000-013-144-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Jul 1, 2024
End Date: Jun 30, 2025
Objective:
Objective 1: Complete biology studies and host range testing of Calomela intemerata.
Objective 2: Write and submit TAG petition for C. intemerata.
Objective 3: Test the host range of Trichilogaster sp. by completing at least 50 species from the test plant list.
Objective 4: Complete temperature dependent development and fecundity studies for Trichilogaster sp.
Objective 5: Establish colonies of Macrobathra arrectella in containment labs in FL from established colonies at ABCL, Australia.
Approach:
Testing the fundamental host range of potential biological control agents. The agents described above will be the first to undergo host range testing to evaluate the safety of releasing them in North America. As mentioned above, this process involves maintaining healthy insect colonies that will display normal feeding behavior. Sixty-four species have been tested for C. intemerata and 18 species have been tested for Trichilogaster at the time of writing, with several additional species in progress. Fundamental host range tests are widely considered extremely conservative but are designed to ascertain what the possibilities (rather than likelihoods) are of an arthropod utilizing a given species for its life cycle. If needed, choice tests and multi-generational tests will be used if a candidate insect uses a test plant species other than A. auriculiformis to complete its life cycle during no-choice testing. However, no species other than A. auriculiformis has supported development of C. intemerata or Trichilogaster spp. in testing so far. For Calomela intemerata, it is highly unlikely that we will encounter a species that supports development, as all the most closely related species (the ones most likely to be hosts) have been tested.
Biology studies: Determining the temperature and other environmental variables necessary for development of candidate biological control agents is of utmost importance. These data help decipher if survival of the agent is possible in the new environment, inform mass rearing activities, and determine temperature dependent development. We will determine the candidate biocontrol agent’s temperature dependent development in environmental chambers starting with monitoring development from egg to adult emergence at temperatures between 20°C and 35°C. We will test temperatures above and below these limits until we find the lower and upper development threshold for each species.
