1a. Objectives (from AD-416):
Develop an attractant for the Diaprepes root weevil based on newly discovered pheromone.
1b. Approach (from AD-416):
Lab and field behavioral response to pheromone and host plant volatiles; gas chromatograph-coupled electroantennogram analysis of Diaprepes odors and frass.
3. Progress Report:
This project is related to inhouse project objective 1: Develop semiochemical-based control methods for citrus pests, particularly Asian citrus psyllid (ACP). We successfully isolated, identified and confirmed the structure and activity of a male-produced pheromone present in the hind gut and excreta of the Diaprepes root weevil. A provisional patent has been awarded. During the first year of this project, we synthesized a significant amount (100 mg) of pure synthetic pheromone, methyl (E)-3-(2-hydroxyethyl)-4-methyl-2-pentenoate . We also identified several plant compounds presumed to be kairomones that may play a role in attraction or repellence of weevils. Field deployment of synthetic male pheromone alone in traps failed to attract weevils when placed in a highly infested and abandoned citrus grove. During the first year of this project, work was started to determine the attraction or repellence of individual kairomone compounds in a laboratory olfactometer. These compounds will then be tested in blends containing the male pheromone to determine possible synergistic effects in an attempt to identify an attractant.