Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/3/2012
Publication Date: 4/19/2012
Citation: Knight, A.L., Light, D.M., Chebny, V. 2012. Evaluating dispensers loaded with codlemone and pear ester for disruption of codling moth (Lepidoptera: Tortricidae). Environmental Entomology. 41(2):399-406. Interpretive Summary: Improvements in the efficacy of mating disruption treatments to control codling moths infesting apple and pear orchards are needed to further reduce grower use of insecticides. ARS researchers at the USDA, ARS, Yakima Agricultural Research Laboratory, Wapato, WA in collaboration with ARS researchers in Albany, CA; and Trécé Inc. tested dispensers loaded with sex pheromone and pear ester and compared them with dispensers loaded only with sex pheromone. In general, dual dispensers outperformed commercial dispensers loaded only with sex pheromone when measured as the proportion of disruption of virgin female-baited traps. Greater disruption of virgin female signaling for mates can translate into reductions in egg laying and subsequent fruit injury. These results suggest that the use of dispensers releasing both codlemone and pear ester could allow reduced use of insecticides targeting codling moth.
Technical Abstract: Polyvinyl chloride polymer (pvc) dispensers loaded with ethyl (E,Z)-2,4-decadienoate (pear ester) plus the sex pheromone, (E,E)-8,10-dodecadien-1-ol (codlemone) of codling moth, Cydia pomonella (L.), were compared with similar dispensers and a commercial dispenser (Isomate®-C Plus) loaded with codlemone. Evaluations were conducted in replicated plots (0.1 - 0.2 ha) in apple, Malus domestica (Borkhausen) during both generations of codling moth from 2007 to 2009. Dispensers were applied at 1,000 ha-1. Male captures in traps baited with virgin female moths and codlemone lures were recorded. Residual analysis of field-aged dispensers over both moth generations was conducted. Dispensers exhibited 1st-order release rates of both attractants, and pear ester was released at a significantly higher rate than codlemone during both time periods. The proportion of virgin female-baited traps catching males was significantly lower with combo dispenser TRE24 (45/110, mg codlemone/mg pear ester) during the 2nd generation in 2007 and the combo dispensers TRE144 (45/75) and TRE145 (75/45) during the 1st generation in 2008 compared with Isomate-C Plus. Similarly, male catches in female-baited traps in plots treated with the combo dispensers TRE144 during the 1st generation in 2008 and TRE23 (75/110) during the 2nd generation, in 2007 were significantly lower than in plots treated with Isomate-C Plus. No significant differences were found for male catches in codlemone-baited traps in plots treated with Isomate-C Plus and any of the combo dispensers. However, male catches were significantly lower in plots treated with the pvc dispenser Cidetrak CM (codlemone-only) than the combo TRE144 dispenser during both generations in 2009