Submitted to: Florida Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/10/2013
Publication Date: 9/1/2013
Citation: Keathley, C.P., Stelinski, L., Lapointe, S.L. 2013. Attraction of a native Florida leafminer, Phyllocnistis insignis (Lepidoptera: Gracillariidae), to pheromone of invasive citrus leafminer, P. citrella: Evidence for mating disruption of a native nontarget species. Florida Entomologist. 96:877-886. Interpretive Summary: The citrus leafminer is an introduced exotic pest of citrus that damages citrus leaves and facilitates the spread of a major citrus disease, citrus canker. We found that the sex pheromone of this species attracted a native Florida leafminer. We tried to disrupt mating of the citrus leafminer by applying its pheromone in citrus groves, but we found that these applications also reduced trap catch of the native species. This study shows that mating disruption efforts targeting the citrus leafminer could disrupt nontarget insects in the ecosystem. Also, if both leafminer species are attacked by the same natural enemy parasitoids, then any action that influences one species may influence the other species as well.
Technical Abstract: We collected a native North American species, Phyllocnistis insignis (Frey & Boll), in traps baited with a 3:1 blend of (Z,Z,E)-7,11,13-hexadecatrienal (triene) and (Z,Z)-7,11-hexadecadienal (diene), two components of the sex pheromone of the exotic citrus leafminer, Phyllocnistis citrella Stainton. No moths were caught in unbaited traps during six months of monitoring. We evaluated seasonal abundance of P. insignis by monitoring trap catch at five sites in central Florida during 2012. P. insignis moths were found in pheromone-baited traps year round with an apparent peak flight in May. In trials designed to evaluate mating disruption of P. citrella, application of triene (825 mg/ha) formulated in SPLAT CLMTM (550 g/ha) disrupted trap catch of P. insignis during a 9 week period following treatment during spring but not during winter (750 mg/ha) using the same formulation (500 g/ha). In a separate experiment, application of both triene (836 mg/ha) and 3:1 blend (836 mg triene + 279 mg diene/ha) loaded onto rubber dispensers disrupted catch of P. insignis males in pheromone monitoring traps designed for P. citrella during a 12 week period following treatment in small (0.14 ha) plots. Also, application of 3:1 blend (880 mg triene + 292 mg diene/ha) formulated in SPLAT CLM (521 g/ha) disrupted trap catch of P. insignis males during a 4 week period following treatment in a 56 ha group of five blocks. These data suggest that mating disruption efforts to control P. citrella influence nontarget populations of related leafminer species such as P. insignis within pheromone-treated citrus groves.