Background: Isomate(®) CM MIST aerosol emitters (Pacific BioControl Corp, Vancouver, WA) containing 36 g of codlemone, (E,E)-8,10-dodecadien-1-ol, were deployed at various densities in a commercial apple orchard to generate dosage-response profiles in order to elucidate the behavioral mechanism of disruption.
Results: Moth captures decreased asymptotically as Isomate(®) CM MIST densities increased. Data fitting to Miller-Gut and Miller-de Lame plots yielded straight lines, with positive and negative slopes respectively. Catch of male moths decreased from 28 trap(-1) in the control to 0.9 trap(-1) at the highest emitter density. Disruption of >90% was realized at emitter densities greater than 5 units ha(-1) .
Conclusion: The resulting set of profiles explicitly matched the predictions for competitive rather than non-competitive disruption. Thus, these devices probably disrupt by inducing false-plume following rather than by camouflaging traps and females. The use of 5 MIST units ha(-1) would be necessary to achieve the same level of codling moth control provided by a standard pheromone treatment with passive reservoir dispensers. The need for only a few aerosol emitters, 2.5-5 units ha(-1) , mitigates the cost of labor required to hand-apply hundreds of passive reservoir dispensers; however, a potential weakness in using this technology is that the low deployment density may leave areas of little or no pheromone coverage, where mate finding may occur. This technology is likely to benefit substantially from treatment of large contiguous blocks of crop.
Keywords: Tortricidae; disruption mechanisms; false plume following; mating disruption.
© 2014 Society of Chemical Industry.