Submitted to: Entomological Society of America, Southwestern and Southeastern Branch
Publication Type: Abstract Only
Publication Acceptance Date: 1/5/2016
Publication Date: 3/13/2016
Citation: George, J., Lapointe, S.L. 2016. Degradation products of citrus volatile organic compounds (VOCs) acting as phagostimulants that increase probing behavior of Asian citrus psyllid[abstract]. Annual meeting of the Southeastern Branch of Entomological Society of America. Paper No. 125.
Technical Abstract: Volatile phytochemicals play a role in orientation by phytophagous insects. We studied antennal and behavioral responses of the Asian citrus psyllid, Diaphorina citri Kuwayama, vector of the citrus greening disease pathogen. Little or no response to citrus leaf volatiles was detected by electroantennography. Glass cartridges prepared with ß-ocimene or citral produced no response initially but became stimulatory after several days. Both compounds degraded completely in air to a number of smaller molecules. Two peaks elicited large antennal responses and were identified as acetic and formic acids. Probing by Diaphorina citri of a wax substrate containing odorants was significantly increased by a blend of formic and acetic acids compared with either compound separately or blends containing ß-ocimene and/or citral. Response surface modeling based on a 4-component mixture design and a 2-component mixture-amount design predicted an optimal probing response on wax substrate containing a blend of formic and acetic acids. Additional volatile organic compounds were tested in component mixture designs to optimize the phagostimulant blend. Our study suggests that formic and acetic acids play a role in host selection by Diaphorina citri and perhaps by phytophagous insects in general even when parent compounds from which they are derived are not active. These results have implications for the investigation of arthropod olfaction and may lead to elaboration of attract-and-kill formulations to reduce nontarget effects of chemical control in agriculture.