Incorporating a novel sex pheromone of apple leaf midge into the apple IPM program for pest monitoring, threshold development, and control
Currently, the only viable option for control of the apple leaf midge is an organophosphate insecticide treatment applied four to six times per year. This is a critical pest in Western Washington, with over 460 acres in production in Whatcom and Skagit Counties; it can cause severe damage in young and newly grafted orchards. The apple leaf midge has not yet become a major pest in Eastern or Central Washington (over 152,000 acres in production) but it has been seen on some farms and will likely become a significant pest in that region over time. Growers affected by this pest are desperate for a viable option for control that does not depend on the use of organophosphate insecticides, which have potential impacts to water quality. A new pheromone for apple leaf midge has recently been developed in the United Kingdom, but has not been tested in Washington. Methods for use of this product as a monitoring tool and a control technique need to be developed for use in Washington State. The product of this proposal will reduce the use of organophosphates to control the apple leaf midge by 75% in Western Washington. Through this proposed product, growers will be engaged in developing project design, monitoring protocols, and control methods. With development of this product, growers in Eastern and Central Washington will have a viable option for management of apple leaf midge, thus reducing the potential for organophosphate use.
Project goals and objectives
• Test new pheromone trap for apple leaf midge
• Reduce use of organophosphates to control apple leaf midge by 75 percent
The project was able to demonstrate that the new pheromone trap could be used to monitor ALCM but not necessarily be used as a management tool to significantly reduce the population of adult midges. Growers are excited by the potential of developing an IPM program using the pheromone traps as a monitoring tool and are interested in further work that might be done to develop a management plan for this pest.
Project results have been developed into a webpage hosted on the WSU Whatcom County webpage at: whatcom.wsu.edu/ipm/alcm/index.html. Information from this project have also been incorporated into the online guide “Integrated Pest Management for Apples: A Guide for Sampling and Decision-Making for Key Apple Pests in Northwest Washington” at: whatcom.wsu.edu/ag/comhort/nooksack/appleipm/index.htm