Foiling the Cranberry Fruitworm

Folks sitting down to their Thanksgiving meal on Thursday aren’t the only Americans who like cranberries. Some cranberry lovers have six legs. But scientists could have a frustrating surprise in store for them.

The cranberry fruitworm is the most destructive insect of this crop in the United States and Canada. Though only about a quarter of an inch long, it sometimes wipes out the entire crop in the cranberry bog.

Recently, scientists with the Agricultural Research Service obtained a patent for a synthetic sex attractant, or pheromone, they developed to foil the pests’ mating. The pheromone, a mimic of the female fruitworm’s own natural mating chemical, strongly attracts hopeful males. But if the artificial pheromone is deployed in a trap, the males are snared instead of free to pursue the objects of their desire.

A pheromone trap could also give a grower a way to know if few or many of the pests are present in the bog. The grower could leave off applying an insecticide unless the number of trapped pests is high enough to show the crop is truly threatened.

Great Lakes IPM, Inc., a company in Vestaburg, Mich., has applied to the research agency for a license on the technology for the fruitworm pheromone. Scientists developed it at ARS’ Yakima Agricultural Research Laboratory in Washington state. It consists of two acetate compounds. One is readily obtained from commercial sources. The other had to be painstakingly synthesized, and the researchers say an economical way to produce it will need to be developed.

Scientific contact: Constance L. Smithhisler, ARS Yakima Agricultural Research Laboratory, Wapato, Wash., phone (509) 454-6550, fax (509) 454-5646, [email protected]