Native nematodes as new bio-insecticides for cranberries

Abstract: In the summer of 2015, an effort was made in central Wisconsin to find an entomopathogenic nematode capable controlling Wisconsin’s cranberry pests. Using a standard baiting method, a nematode of the Oscheius genus was collected from the mossy, sandy, peat-filled soils of a wild cranberry marsh. This nematode may be a new subspecies of the nematode Oscheius onirici Torrini (Rhabditida: Rhabditidae), and is tentatively referred to as Oscheius onirici sub. wisconsinensis. It is effective at killing sparganothis fruitworms in laboratory conditions designed to imitate the bed of a cranberry marsh. Furthermore, it can kill cranberry fruitworm prepupae in the lab. During the summer of 2016, a greenhouse-scale experiment confirmed that the nematode can suppress redheaded flea beetle populations at levels comparable to insecticides. A project is under way in Monroe County, Wisconsin, to test the nematode’s flea beetle suppression abilities within a commercial marsh. Furthermore, some evidence from an in vitro bioassay suggests that a bacterium associated with the nematode, can antagonize the growth of fungi collected from infected cranberries. This bacterium, which is in the Bacillus genus, can even protect rye grass from the Rhizoctonia fungus, under laboratory conditions. This presentation is not available for downloading