1a. Objectives (from AD-416)
To design and optimize semiochemical-based methods for control of major insect pests such as the citrus leafminer, Phyllocnistis citrella. In addition to field trials, laboratory research will address fundamental aspects of mechanisms underlying mating disruption.
1b. Approach (from AD-416)
Replicated, multilocational field trials will be established in commercial citrus groves to document application rates, coverage and deployment methods to optimize control of major citrus pests such as the citrus leafminer and associated citrus canker disease. Signals from antennae of citrus leafminer and other insects of interest will be recorded in response to odors collected from host plants and conspecifics. Antennae will be connected to a gas chromatograph-coupled electroantennogram (GC-EAD) and compounds of interest will be identified by GC-Mass Spectrometry (GC-MS).
3. Progress Report
This project is related to inhouse objective 1: Develop semiochemical-based control methods for citrus pests, particularly Asian citrus psyllid (ACP). Semiochemical-based methods of control were pursued for citrus leafminer (CLM). Field trials were conducted in collaboration with the University of Florida, Lake Alfred to identify optimize control of CLM through mating disruption (MD) and an attract-and-kill product. Field experiments demonstrated highly effective disruption over several weeks in commercial groves following application of a very small amount of one compound of the CLM sex pheromone in a slow-release matrix, SPLAT™ (Specialized Pheromone & Lure Application Technology, ISCA Technologies Inc., Riverside, CA). A field trial testing formulations of an attract-and-kill formulation (MalEx™, Alpha Scents Inc., Portland, OR) failed to show activity in an abandoned citrus grove in 2010. If successful, these products would be the first semiochemical-based methods of insect pest control available to Florida citrus growers. Gas chromatograph-coupled electroantennography (GC-EAD) was used in conjunction with GC-Mass Spectrometry (GC-MS) to identify volatile compounds that elicit antennal response in the Asian citrus psyllid (ACP), the vector of citrus greening disease. Recording from ACP antennae has been technically challenging and it is still not clear that ACP adults rely upon chemical cues to locate host plants or conspecifics. GC-MS was used to generate a database of volatile compounds produced by a highly susceptible host plants and some resistant plants. These compounds will be evaluated in behavioral assays in an attempt to identify attractants and/or repellents. Such compounds would be useful for development of new control methods for citrus growers. Progress was monitored through direct involvement in lab and field activities, research meetings and discussions with collaborators at U.S. Horticultural Research Laboratory (USHRL) and University of Florida-Citrus Research and Education Center(UF-CREC), telephone calls and email communication.