University of Georgia entomologist Michael Toews says there’s a wasp that controls kudzu bug populations in Asia, where the kudzu bug originates. The wasp might do the same in the U.S.
“(Finding a predator) is exactly what we need to do for long-term suppression,” said Toews, a researcher with the UGA College of Agricultural and Environmental Sciences. “The problem is you can’t just go collect a bug from another land and release it. You have to study all of its non-target effects. Sometimes you can create more problems than you’re solving when you release a new species in a foreign land.”
The wasp attacks kudzu bug eggs and kills the larvae before they hatch. The uncertainty surrounding the wasps’ potential impact in North America has Toews and fellow entomologists concerned. U.S. Department of Agriculture and UGA entomologists are studying the wasp to see if it will parasitize other insects native to the U.S.
If untreated, kudzu bug damage can result in soybean yield losses ranging from 20-60 percent.
“This is a major production challenge for us because this invasive insect pest has had no natural controls in the United States. Thisinsect is native to Asia, China and Japan, specifically,” Toews said. “In those lands, there are parasitoid wasps that manage these populations. In fact, they’re not considered crop pests in their native land. But when it was introduced into North America and the Western Hemisphere, the parasitoid did not come with it, so that bug has been able to expand very, very rapidly.”
In 2012, researchers applied for the necessary USDA permit to release the wasp. Scientists must first demonstrate new pests are safe and do not alter the ecosystem before they are released. This usually takes a couple of years, but the parasitoid wasp was found in Georgia and Alabama last summer. Toews calls the findings accidental and is uncertain how the wasp made it to the U.S.
Genetic testing shows the newly detected wasp population is different than the strain being examined under quarantine. Research teams throughout the Southeast are monitoring the potential spread of the parasitoid wasp during this year’s growing season.
“Entomologists, stakeholders and growers are all hoping that this little parasitoid is going to help us manage our kudzu bug populations,” Toews said. “ We’re all hopeful that it’s going to happen, but this is a new land (for the wasp), and we don’t really know if the same amount of control will be exerted as in its native area,” Toews said.
Find out more about this wasp and other work related to kudzu bug control.