An attract-and-kill strategy for Asian citrus psyllid

Authors: George, Justin; LAPOINTE, STEPHEN

Submitted to: International Research Conference on Huanglongbing
Publication Type: Abstract Only
Publication Acceptance Date: 10/31/2016
Publication Date: 3/15/2017
Citation: George, J., Lapointe, S.L. 2017. An attract-and-kill strategy for Asian citrus psyllid. International Research Conference on Huanglongbing. International Research Conference on Huanglongbing V. Available: Journal of Citrus Pathology. p. 14-15.

Interpretive Summary: Phytophagous insects including Asian citrus psyllids (Diaphorina citri Kuwayama) (ACP) use multiple sensory modalities [vision, olfaction, contact chemoreception, gustation (taste), perception of auditory or vibrational stimuli] to locate host plants or conspecifics. Many studies have reported that ACP is strongly attracted to bright yellow and light green. Several chemical blends have been suggested as ACP attractants, but only modest attraction has been demonstrated in the field. George et al. (2016) found that acetic and formic acids were highly excitatory to antennae of male and female adult ACP. These two compounds occur in the atmosphere surrounding citrus orchards and originate as breakdown products of common plant volatiles including ß-ocimene and citral (geranial and neral) that oxidize spontaneously in air. A mixture of these compounds incorporated into SPLAT induced increased probing by ACP. Addition of a third compound (para-cymene) further increased probing in a 3-component blend. This blend acts as a phagostimulant by increasing the number and the length of probes into a wax substrate containing the 3-component blend. Phagostimulants may be useful to deliver “payloads” such as an engineered RNAi construct or to enhance ingestion of toxicants as part of an attract-and-kill strategy. Furthermore, ACP infected with the citrus greening pathogen probed the 3-component phagostimulant blend more often compared with healthy ACP. A number of sensory stimuli (cues) will be incorporated into the design of an attract-and-kill device to optimize attraction of ACP and mortality after psyllids land on the device. The goal of this project is to develop an economical and environmentally appropriate management strategy for ACP that exploits what we have learned about the psyllid behavior including its response to visual, olfactory, and gustatory stimuli.

Technical Abstract: Asian citrus psyllids (ACP) transmit the pathogen responsible for citrus greening disease. Psyllids use color, smell, taste and vibrational cues to identify their host plants and conspecifics. The main goal of this project is to develop an attract-and-kill device strategy that will exploit the psyllid’s responses to these sensory cues. Adult psyllids will be attracted to the trap by color and odor; after alighting, psyllids will be induced to probe and attempt to feed by the presence of phagostimulants (compounds that induce ACP probing and feeding) in a wax matrix attached to the surface of the device. Psyllids may then be killed by a contact insecticide or other agent contained in the wax matrix.