You are here: Home / News / Potential New Pest - spotted wing drosophila

Viticulture & Enology

Potential New Pest - spotted wing drosophila

 New Invasive Species in Oklahoma Could Mean Trouble for Fruit Growers

  • Phil Mulder, Eric Rebek, and Jackie Lee
  • Department Head, Extension Entomologist, and Pesticide Coordinator

On June 27, traps placed by a fruit grower in Tulsa County captured a rather suspicious-looking fly, which was subsequently packed up by the County Educators and shipped to the Department of Entomology and Plant Pathology at Oklahoma State University. This capture has been confirmed as the spotted wing drosophila (SWD). This rather small vinegar fly or fruit fly attacks ripening or ripe soft fruits including; blackberry, blueberry, boysenberry, grapes, raspberry, strawberry, and tree fruits (peach, apricot, cherry, mulberry, nectarine, persimmon, and plum). It has also been recorded attacking other fruits such as melons and tomatoes.

Spotted wing drosophila was first detected in the United States in California in 2008, where it eventually spread north to British Columbia and south all the way to Florida. As recently as 2012, SWD was confirmed in Arkansas, Colorado, Idaho, Illinois, Indiana, Iowa, Kentucky and Minnesota. Based on its rapid movement across the country and the fact that the flies cannot fly very far, it is apparently being spread by humans transporting infested fruits.

What makes SWD potentially more economically important than other fruit flies is its ability to cut into intact fruit, using their serrated ovipositor to inject eggs under the skin. This allows the

subsequent larval stage to be present during ripening and can lead to detection in ripe fruit after harvest. They are also capable of introducing sour rot or fungal diseases, further affecting the quality of the fruit. In addition, while most Drosophila flies will take advantage of damaged and/or rotting fruit, SWD can contaminate uncompromised (harvested) product and cause fruit flesh to break down and collapse.

Read more . . .