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ARS Home » Pacific West Area » Wapato, Washington » Temperate Tree Fruit and Vegetable Research » Research » Publications at this Location » Publication #329077

Research Project: New Technologies and Strategies to Manage the Changing Pest Complex on Temperate Fruit Trees

Location: Temperate Tree Fruit and Vegetable Research

Title: Mapping global potential risk of establishment of Rhagoletis pomonella (Diptera: Tephritidae) using MaxEnt and CLIMEX niche models

Author
item Kumar, Sunil - Colorado State University
item Yee, Wee
item Neven, Lisa

Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/1/2016
Publication Date: 7/24/2016
Citation: Kumar, S., Yee, W.L., Neven, L.G. 2016. Mapping global potential risk of establishment of Rhagoletis pomonella (Diptera: Tephritidae) using MaxEnt and CLIMEX niche models. Journal of Economic Entomology. 109(5):2043-2053.

Interpretive Summary: The apple maggot is a major quarantine pest of apples in the U.S. To reduce the threat of apple maggot to export countries and to facilitate the movement of commercial apples, an assessment of potential risk of establishment of apple maggot in export countries is needed. Personnel at the USDA-ARS Yakima Agricultural Research Laboratory in Wapato, WA, and Colorado State University in Fort Collins, CO used the predictive models MaxEnt and CLIMEX to determine global potential risk of establishment of apple maggot. Both models correctly predicted the known distribution of apple maggot in North America and mostly agreed on climatic suitability worldwide for the fly. Our results are important because they can be used to make science-based international trade decisions on apple movement by policy makers.

Technical Abstract: The apple maggot, Rhagoletis pomonella (Walsh) (Diptera: Tephritidae), is a major quarantine pest of apples (Malus domestica Borkhausen) in the United States. Apple maggot is found only in North America and negatively impacts the apple industry in the western U.S. by reducing grower access to export markets. To reduce the threat of apple maggot to export countries and to facilitate the movement of commercial apples, an assessment of potential risk of establishment of apple maggot is needed to predict which regions are suitable or unsuitable for the fly. We used a correlative niche model MaxEnt and a mechanistic model CLIMEX to model global potential risk of establishment of apple maggot. MaxEnt model was developed by integrating apple maggot occurrences with global climatic variables. Apple (a major host of apple maggot) climatic suitability was used to include species interactions in MaxEnt model. CLIMEX model was developed using published apple maggot physiological tolerance thresholds. Both MaxEnt and CLIMEX models correctly predicted the known distribution of apple maggot in North America, met biological expectations when projected to the world, and mostly agreed on climatic suitability worldwide for the fly. Degree days at 6.7°C, elevation, precipitation seasonality, and apple climatic suitability were the most important predictors associated with apple maggot distribution in North America. Our results can be used to make science-based international trade decisions by policy makers, and for monitoring apple maggot potential introductions in countries where it currently does not occur.