Use of Ethyl and Propyl (E,Z)-2,4-decadienoates in Codling Moth Management: Improved Monitoring in Bartlett Pear with High Dose Lures

The propyl and ethyl esters of (E,Z)-2,4-decadienoic acid were evaluated in gray halobu-tyl septa as kairomone lures for both sexes of codling moth, Cydia pomonella (L.). All studies were conducted in ‘Bartlett ’ pear orchards with moderate to high codling moth adult population densities and treated with sex pheromone dispensers for mating disrup-tion. Variable results were obtained with kairomone loading experiments. Increasing the lure loading to 40.0 mg of either the ethyl or propyl ester significantly increased male and total moth catch in separate experiments. However, in other tests with the ethyl ester no difference was found in total moth catch in traps baited with 0.1, 1.0, 3.0 or 10.0 mg versus 40.0 mg lures. The 40.0 mg ethyl and propyl ester lures were both more effective than a 3.0 mg ethyl ester lure and comparable to a sex pheromone lure in detecting the beginning of codling moth flight in the spring generation. No difference was found in moth catch between 40.0 mg propyl and ethyl ester lures. Significantly more females were caught in traps baited with 1.0 – 10.0 mg than with 1.0 – 100.0 µg lures loaded with the ethyl ester. In general, kairomone lures caught significantly fewer moths than sex pheromone lures