Submitted to: Western Orchard Pest and Disease Management Conference
Publication Type: Abstract Only
Publication Acceptance Date: December 15, 2003
Publication Date: January 14, 2004
Citation: Knight, A.L. 2004. How we can make codling moth mating disruption work. Western Orchard Pest and Disease Management Conference. p.4. Interpretive Summary: Abstract only; please refer to technical abstract section
Technical Abstract: The efficacy of several approaches that use the sex pheromone of codling moth to manage this important pest in apple have been investigated over the past 14 years. These tactics include the use of hand-applied dispensers, microencapsulated sprayables, widely-spaced high emission sources such as puffers and the Pheromone Mop, attract and kill paste drops, and the application of chopped capillary fibers. It has been difficult to demonstrate that the use of hand-applied dispensers can adequately prevent mating by codling moth. Nor does increasing the density of dispensers noticeably increase the disruption of mating. A delay in egg hatch (= delay in mating) was demonstrated in three orchards treated with a full rate of Isomate C+. Whether a similar delay occurs in orchards treated with reduced rates of dispensers is unknown. The current use of microencapsulated sprayable formulations applied with air blast can be improved by increasing the number of capsules deposited in the canopy and especially by increasing the density of leaves with a high number of capsules, > 20. This can be accomplished by reducing the amount of water applied, reducing the spray pressure of the application, and with the addition of an effective sticker. The use of widely spaced high emission dispensers such as puffers and Pheromone Mops appear to be more effective in disrupting mating than the use of hand-applied dispensers. In addition, their use has also been shown to be effective in ensuring low levels of codling moth fruit injury. The sex pheromone-based attracticide approach can be effective if the appropriate number of drops is applied to compete successfully with the density of calling females. The Last Call paste formulation was found to form a larger oil-based halo around each drop that is effective in killing moths. We also found that the attractiveness of Last Call droplets is significantly reduced in orchards treated with Isomate dispensers the previous season or when used as a supplemental border application. The successful deposition and retention of the chopped fibers mixed with an adhesive remains a serious limitation with this approach. An alternative approach using a paintbrush was much more effective in depositing fibers in the canopy.