1a. Objectives (from AD-416):
1) Identify behaviorally active semiochemicals for invasive insect species such as the coffee berry borer and the coconut rhinoceros beetle and other invasive pests to be determined in collaboration with cooperator. 2) Synthesize the pheromones and other semiochemicals as needed and validate attractiveness in lab and field bioassay. 3) Identify optimal ways to utilize identified behaviorally active semiochemicals such as early detection and/or mass-trapping. 4) Develop systems approaches against fruit flies that allow movement from quarantine areas.
1b. Approach (from AD-416):
Our approach is to collect authentic pheromones from live ‘calling’ females and/or clipped abdominal tips and or plant kairomones from host plants and using headspace collection and or tip extraction to identify the chemicals present using GC-MS. Electrophysiological studies will be employed to identify biologically active constituents using GC-EAD on insect antenna. Those with activity will be tested and formulated for testing in a flight tunnel bioassay or other laboratory apparatus and if possible in the field. Next the pheromone and/or semiochemical will be synthesized and lures used to conduct field evaluations. Specifically, we would like to correlate capture of targeted invasive species to field populations and damage levels in the different cropping systems unique to Hawaii. Lastly we hope to use semiochemicals in potential control tactics. Identify and deploy systems approaches for fruit flies.
3. Progress Report:
The goal of the project is identification and field use of semiochemicals of invasive insect pests in Hawaii; this understanding directly contributes to Objective 2 of the in-house project. Studies were conducted to locate and identify the active pheromone components of the fruit piercing moth (FPM). We encountered problems with obtaining the moths and had to import them from Guam. Dissections and headspace collections were carried out on the scarce populations of insects that were available. We also set up electrophysiology experiments but as yet have not identified electrophysiologically active compounds. Further studies will be conducted when adequate populations become available. Electrophysiological activity was shown by the coconut rhinoceros beetle (CRB) to various pheromone and plant headspace volatile collections. Isolation and identification of active compounds are currently being investigated. Some initial behavioral responses were also observed to active identified compounds using a glass Y-tube “olfactometer”. Identification of active compounds from developing coffee berries in the field are currently being investigated using sequential headspace collections of coffee berries as they ripen through the growing season. Active compounds previously identified in the laboratory have also shown some attraction in field traps when combined with a known attractant. Tomato susceptibility to forced infestation of fruit flies with different degrees of ripeness will be documented as part of a systems approach for exportation.