Stink bugs attack cherries
Stink bugs, typically an apple pest, can be a problem in late-maturing cherries. Photo by Whitney Cranshaw, Colorado State University, Bugwood.org
Stink bugs have been a problem in Washington apple orchards, but with the expansion of the cherry industry they begun attacking late-maturing cherries, in some cases causing severe injury, reports Dr. Jay Brunner, entomologist and director of Washington State University’s Tree Fruit Research and Extension Center in Wenatchee.
The species that most commonly attacks apples is the consperse stink bug Euschistus conspersus, but the species that has caused most of the crop losses in sweet cherries is the less well known Chlorochroa ligata, which has no common name.
Researchers have shown that the pheromone of E. conspersus can be used for monitoring the pest and that it could be used with insecticides to manage stink bugs through an attract-and-kill approach on border plants. They are working on a similar strategy for C. ligata.
Dr. Jocelyn Millar at the University of California, Riverside, has identified and synthesized the pheromone for C. ligata and shown that it is attractive to adult stink bugs. Research by Brunner and his colleagues at WSU last year showed that the pheromone could be successfully used to trap both sexes and nymphs of that species of stink bug.
Brunner said stink bugs are a threat to all apple, pear, and now cherry orchards that have late maturing fruit, especially in locations near native habitat. They are a particular threat to organic apple and cherry production because there are no effective, organically certified products available to control the bugs.
Brunner hopes to find the optimum release rate for the C. ligata pheromone, and learn more about the life history and ecology of the pest in order to develop tactics to manage it. Future research will focus on developing a lure with both pheromones that could be used in traps along orchard borders as an attract-and-kill device for both stink bug species in both conventional and organic orchards.
The project is supported by the Washington Tree Fruit Research Commission.