New Pest Management Choices Provided Fruit Growers

Spotted wing fly struggle gets new weapons.

Published on: Apr 17, 2014

Entomologist Lynell Tanigoshi and his colleagues at Washington State University have devised an effective system to help soft fruit growers control what has become their top public enemy: spotted wing drosophila fruit flies.

Their system, insect resistant management, rotates spraying with a variety of chemical applications to reduce resistance to insecticides.

"We're trying to establish a bio-fix for growers to be able to begin their pesticide treatments when berries are actually ripening, and then – based on their specific crop and growing conditions – apply appropriate pesticides every six to eight days through harvest," explains Tanigoshi.

The goal is find intervals when pesticide applications are not needed and to determine what rotations work best, he notes. "We're trying to educate people to make intelligent choices based on scientific evidence so we can move in the direction of finding more ways to get off our addiction to calendar sprays," adds Tanigoshi.

WSU entomology program team members, from left, Lynell Tanigoshi, Bev Gerdeman and Hollis Spitler check for insects on young strawberry and raspberry plants.
WSU entomology program team members, from left, Lynell Tanigoshi, Bev Gerdeman and Hollis Spitler check for insects on young strawberry and raspberry plants.

Spotted wing has established itself as the most economically damaging pest to blueberry and cranberry production in the Pacific Northwest.

His advice is part of a report, "Spotted Wing Drosophila in Berries – 2013 Findings," which he and fellow entomologists Beverly Gerdeman and Hollis Spitler compiled.  The report is the result of the team's small fruit pest management program research, which focuses on new and cost-effective ways to help the state's $100 million small fruit industry.

"After four years of fighting this insect, we better understand the biology and behavior of the spotted wing drosophila," he believes.

The next step in the program is to develop new mode-of-action  insecticides which will prevent tolerance and target different sites in order to interrupt the fly's reproductive cycle, which in the Northwest can be as rapid as three to four generations hatched each year."

At stake are some very valuable industries to the Northwest, including 16,000 acres of blueberries in Oregon and Washington.