Improving the attractiveness of the odor-baited trap tree approach to adult plum Curculios (Coleoptera: Curculionidae) in New England, USA

The implementation of appropriate monitoring systems assists growers in determining the need and proper timing of insecticide which is vital for successful crop production. The odor-baited trap tree approach is a low input and grower-friendly IPM system involving a synergistic lure consisting of benzaldehyde (a plant volatile) and grandisoic acid (the PC aggregation pheromone). This lure was developed 20 years ago for plum curculio (PC) monitoring and management. However, the high cost of the lure and the degradation of benzaldehyde by UV light have limited grower adoption. The main goal of my research was to improve the attractiveness of trap tree approach for PC by finding a replacement to benzaldehyde. We evaluated the attractiveness of odor-baited trees (thereafter called trap trees) baited with PredaLure (methyl salicylate-containing lure) to PC versus trap trees baited with benzaldehyde and grandisoic acid, as well as unbaited trap trees. PC activity was monitored using three approaches: (1) black pyramid traps fitted with boll weevil trap, (2) limb jarring, and (3) PC oviposition injuries on apple fruitlets. Overall, trap trees baited with PredaLure were found to be as attractive or more attractive to PC and received significantly higher levels of PC injury injury when compared to trap trees baited with the long-established synergistic lure. More research needs to be done to evaluate the attractiveness of PredaLure to PC in apple orchards at New England, USA.