Submitted to: Washington State Horticulture Association Proceedings
Publication Type: Proceedings
Publication Acceptance Date: December 20, 2000
Publication Date: May 20, 2001
Citation: KNIGHT, A.L. APPLYING SEX PHEROMONES - FROM PUFFERS TO AIR-BLAST SPRAYERS. WASHINGTON STATE HORTICULTURE ASSOCIATION PROCEEDINGS. p. 161-163. Interpretive Summary: The adoption of sex pheromones for management of codling moth has been rapid during the past 10 years. New approaches are being tested that in- clude the use of sprayable micro-encapsulated formulations and the use of battery-powered aerosol devices. Studies conducted during 2000, showed that the effectiveness of the sprayable formulations is extended for sev- eral weeks by depositing more of the formulation in the canopy of orchard through a low-volume over-the-top sprayer. The current use of air blast sprayers deposits a greater proportion of the pheromone on the ground and this material is effective for <7 days. The use of an internal grid of aerosol devices in combination with a 10-meter perimeter application of hand-applied dispensers has been tested for both codling moth and oblique- banded leafroller. During the 2000 season we found that this low density of puffers was as effective in reducing fruit injury by codling moth as the eprogram where orchards are treated only with hand-applied dispensers. Puffers that also released leafrollere pheromone reduced fruit injury by obliquebanded leafroller more than 60% compared with injury levels found in orchards not treated with the leafroller pheromone.
Technical Abstract: New developments in applying the sex pheromone of codling moth, Cydia pomonella include the use of micro-encapsultated formulations and aerosol dispensers. Applying the sprayable codling moth formulation with a low volume sprayer extended the length of disruption of female-baited traps in replicated plots versus the use of an air blast sprayer applying the phero- -mone in a high volume of water. Capsules deposited on the ground were effective for <7 days. A new sex pheromone-based strategy was developed that employs the use of battery-powered aerosol devices placed 50 m from the orchard's edge and spaced 100 m apart. In addition, each orchard was treated with hand-applied Isomate-C+ dispensers in a 10-m band around the perimeter. During 2000 the effectiveness of puffers for C. pomonella alone or for both C. pomonella and Choristoneura rosaceana was evalauted in sixteen 40-acre orchards. The mean C. pomonella injury in the puffer- treated orchards was not significantly different than in the Isomate-C+ comparison blocks. Fruit injury by C. Rosaceana, however, was significantly lower in the dual puffer-treated versus the orhcards not treated with leafroller pheromone.