Issue link: http://read.dmtmag.com/i/84143
One key idea is, don't rely on one or two predators or parasites. A concept new to many growers is that biocontrol does not have to give 99 per- cent control of the pest, like a biopesticide such as Bt does, he said. A number of species, each providing some control of multiple stages of the stinkbug, can greatly decrease the overall population levels that develop outside of the orchards. This reduces the chances of them moving into orchards at levels high enough to cause economic damage. Another effort is attempting to find pheromones that will act as lures—either of the stinkbug or of its predators—to make the insect easier to monitor. The basic ecology of the stinkbug is also being studied. "We're just starting to understand a little more about the host plants they're using and where they spend their time when they're not in orchards," Leskey said. A new Web site, www.stopbmsp.org, will become active soon, offering state- by-state information about the bug. • Parasite studied in quarantine Will the parasitic wasp S attack native stinkbug species? by Geraldine Warner cientists around the United States are studying a natural enemy of the brown marmorated stinkbug that has been imported from China with the hope that it might help keep the pest in check in this country. The parasitic wasp Trissolcus halyomorphaewas collected in the fall of 2011 by U.S. Department of Agriculture scientists in China, where it was found emerg- ing from brown marmorated stinkbug eggs. The species was not known before. It was imported into a USDA rearing facility in Delaware and is being held in quarantine until scientists determine if it would safe to release as a potential biocontrol. A concern with the import of exotic biocontrol agents is that they might attack native species, so research is focusing on how the wasp reacts to nontarget stinkbug species, some of which are beneficial. Christopher Hedstrom, graduate research assistant with Oregon State University, is working with the new parasite at the university's USDA-approved quarantine facility in Corvallis. First, the scientists determined that the parasite does attack and kill eggs of the brown marmorated stinkbug (Halyomorpha halys). Now, they are exposing the parasite to eggs of stinkbug species that are native to Oregon and the Pacific Northwest to find out if it attacks them, too. Initially, no-choice tests are conducted, which involve putting a parasite in a vial with the egg of one species to see if it attacks. If it does, more tests are conducted where the parasite is exposed to multiple species, to study its preferences. Hedstrom said he and his colleagues are about halfway through screening native stinkbugs for their vulnerability to the wasp. If their study proves that the parasite only attacks the brown marmorated stinkbug and is not a threat to other species, the next challenge will be to find out if the parasite can survive in West Coast conditions. Because of differences in climate, such as temperature and rainfall, imported natural enemies often fail to become established. The Oregon Department of Agriculture has received funding from the USDA to con- duct the studies. It is hoped that, if all goes well, the parasite could be reared in insec- taries and released into the natural environment at about the same time that brown marmorated stinkbug populations take off in the Pacific Northwest, perhaps in two or three years' time, in an attempt to avoid the kind of damage that the East Coast has expe- rienced. The bug has been in Portland since 2004 and recently spread to agricultural areas in Oregon, including the Willamette Valley and Hood River. Helmuth Rogg, manager of the Oregon Department of Agriculture's insect pest prevention and management program, stressed in a press release that the brown mar- morated stinkbug has proven a difficult pest to control, so there are big hopes for biological control. "On a pest risk scale of one to ten, I would say the brown marmorated stinkbug is a 15," he said. "Hopefully, time is on our side, and we can avoid the big outbreak we've seen in eastern states. Biological control can help." Scientists in Florida and Michigan are also screening the same parasite against native stinkbugs in those regions and will share their results before any decision is made about rearing the wasp in large enough numbers to release into the environment, the Department of Agriculture said. • www.goodfruit.com soil fungicide and nematicide (includes chloropicrin) with Telone* C-17 CUSTOM ORCHARD FUMIGATION Chris Ford/Dale England/Len England 509 687-9572 Chris, cell/text: 509 366-5180 Dale, cell/text: 509-860-9058 Len, cell: 509-679-7124 E-mail: customorchardfumigation@live.com Visit us at customorchardfumigation.com !" Food Safety • Process Control Verification • On-Site Sampling Programs • MRL Testing 3019 GS Center Road Wenatchee, WA 98801 509-662-1888 509-662-8183 (fax) Water Quality • Drinking Water • Wastewater Discharge • Regulatory Reporting Assistance Your Analytical Laboratory Since 1978 509-452-7707 • 509-452-7773 (fax) 800-545-4206 1008 W. 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