"Before our project, little was known about the chemical ecology of cerambycid beetles or their use of attractant pheromones, and the pheromones of only a few species had been identified," Millar said. "Our longer-term goals are to gain a better understanding of which subfamilies, tribes, and genera are likely to use pheromones, and, within those groups, to determine the types of chemicals that are used as pheromones. This will allow us to predict whether new invaders are likely to use pheromones that we can exploit, and, if so, what those pheromones may be.
"Conversely, if we can predict which species do not use attractant pheromones, there would be no point in looking for such compounds, and we could focus on finding the chemicals that attract these species to their host trees."
During the second year of the three-year project, Millar and Hanks identified two diagnostic characteristics, one behavioral and one based on external appearance, that allow entomologists to immediately assess whether a species is likely to have a male-produced attractant pheromone. Their study also found the first examples of powerful female-produced pheromones in the Cerambycidae family.
"These morphological features and specific behaviors are reliably associated with pheromone use by cerambycid beetles," Millar said. "Specifically, for a large group of species, we found males have a particular type of glandular structure to produce pheromones. These males adopted a very specific stance when they were releasing their pheromones, akin to doing pushups. Thus, from simply checking for the presence of the glands, or observing the behavior of a new i
|Contact: Iqbal Pittalwala|
University of California - Riverside