1a. Objectives (from AD-416)
Trade barriers exist on the import of apples and cherries from the Pacific Northwest based on the presumed risk of temperate fruit flies entering and establishing in export market countries. A multi-faceted or systems approach taking into account potential fly distribution, fly detection, and fly identification components are addressed in this project. In this project we plan to evaluate potential fly distributions through modeling, evaluate attractants for flies, evaluate methods to discriminate closely related fly species, and to develop collaborations for modeling risk of infestations in orchards.
1b. Approach (from AD-416)
A. Collect existing data on basic biology of apple maggot in the Eastern U.S. and Mexico versus Pacific Northwest including obligate diapausing, facultative diapausing, and non-diapausing portions of the population. Collect existing data on WCFF in the Pacific Northwest. Data will include host range, distribution maps, climatic data, growth optima, upper and lower thermal limits, degree day models, diapause induction, maintenance, and completion. B. Enter existing data on AM and WCFF biology as well as environmental data of importing countries into risk modeling programs. Determine baseline for risk, and identify research gaps. C. Determine critical parameters (i.e. photoperiod, chilling requirement) for diapause induction and completion in apple maggot from Washington State. We will include obligate diapausing, facultative diapausing, and putative non-diapausing portions of AM populations. D. Determine critical parameters for growth and development of apple maggot and Western cherry fruit fly under climatic conditions specific for tropical regions. E. Identify improved attractants, such as fruit volatiles, for apple maggot fly in the Western U.S. Improved attractants will improve the accuracy of the data used for pest distribution, numbers (load factor), and help in establishing and maintaining quarantine areas. In addition, improved trapping methodologies will increase confidence in pest control measures with our trading partners. F. Demonstrate that morphometric and molecular methods can reliably separate the apple maggot and snowberry maggot. Misidentification of a non-quarantine pest as a quarantine pest can adversely affect trade and negatively impact risk assessment models. G. Hold a regional workshop on Western cherry fruit fly. The specific topic to be addressed is how to develop a model that can be used to predict the probability of an orchard being infested with cherry fruit fly.
3. Progress Report
This project is an extension of research on the management of insect pests of temperate tree fruits and addresses objective 5 of the related in-house project. The project, Pest risk analyses for temperate fruit flies in exported fruits, relates to National Program 304 4A, Protection of Postharvest and Quarantine: Insect Pests of Fresh Commodities, in that it addresses the potential of temperate fruit flies in tree fruits shipped from the Pacific Northwest to tropical countries. This has become an important export issue with the Northwest Tree Fruit industry. Although the biology of these pests where they are established in the U.S. exists, there are no data on their potential to establish and spread in tropical Asian-Pacific countries. Information on the biology, ecology, and physiology of apple maggot and Western cherry fruit fly are being collected and tabulated into electronic databases to be used in ecological niche models that can predict the potential for these pests to establish and spread in tropical climates. This is the first field season of the three year project. An extensive trapping program for Western cherry fruit fly in Central Washington and apple maggot throughout Central and Western Washington have been initiated. Experiments on the effects of tropical environments on the growth and development of these two species have been developed and initiated. Monitoring of activities and progress on this project was accomplished by direct supervision of on-site employees, and use of site visits, email, and telephone to communicate with off-site collaborators.