Field experiment of a three-chemical controlled-release dispensers to attract codling moth (Cydia pomonella) (Lepidoptera: Tortricidae)

Abstract

Male and female codling moths, Cydia pomonella (Lepidoptera: Tortricidae), were shown to be attracted to a threechemical kairomonal lure consisting of pear ester, acetic acid, and n-butyl sulfide. A controlled-release device based on sachets was developed in the laboratory and field tested to optimize the attractiveness of C. pomonella to this combination of attractants, and to decrease material costs associated with the controlled-release of these chemicals. The lure was most effective when pear ester was released from a separate dispenser than when combined acetic acid and n-butyl sulfide. We found that acetic acid and n-butyl sulfide can be combined into one device without decreasing C. pomonella trap catches and that there is minimal pear release rate before trap catch is negatively affected. A sachet-based controlled-release system of pear ester, acetic acid, n-butyl sulfide is a cost-effective alternative to a vial and septa controlled-release system and allows for easier quantification of ideal release rates. A reduction in material costs associated with management are important in promoting the adoption of attract-Andkill and mass-Trapping paradigms for C. pomonella management. These findings also have important consequences in interpreting studies that use different loads of pear ester, and emphasize the need to better understand the release rates of attractants.