What is in this article?:
- Tiny wasp may be key to kudzu bug control
- One option in tool kit
• A tiny Asian wasp may be the best option for kudzu bug control.
• The wasp lays its own egg in each kudzu bug egg, and the developing wasp larva destroys the kudzu bug egg as it develops.
THE BEAN plataspid or kudzu bug.
One option in tool kit
“Using classical biological control is an option in the tool kit,” said Ruberson, an entomologist in the UGA College of Agricultural and Environmental Sciences. “There are several known parasitoids, one pathogen from India and one predator from Pakistan that are all natural enemies of the kudzu bug.”
UGA scientists “know very little” about the predator and the pathogen, Ruberson said. They are working closely with Keiji Takasu of Kyushu University in Fukuoka, Japan who has extensive knowledge of the wasp.
It has to be safe for the ecosystem
“We have to demonstrate the safety of the organism before it can be released,” he said. “We want to make sure it’s a safe release so it doesn’t mess up the ecosystem.”
Ruberson and his colleagues are applying for a USDA permit for parasitoid release and will follow the required steps to ensure the wasp isn’t a danger to native insects and pests.
UGA researchers are still searching for natural kudzu bug enemies that are native to Georgia and the Southeast.
“We haven’t found any egg parasites in the past two years in Georgia on kudzu or soybeans,” Ruberson said. “We have found some chewed kudzu bug eggs that have been damaged by something. We just don’t know by what yet.”
Kudzu bug buffet
Jones and Ruberson set up makeshift kudzu bug buffets in their laboratories to find out whether or not native egg parasites and predators like to dine on the new pest. Native egg parasites “show no interest” in the eggs, Ruberson said.
He offered common predators a meal of 10 kudzu bug nymphs and observed their dining habits. Two predator species (big-eyed bugs) ate all the nymphs and the rest ate 20 to 30 percent of the nymphs.
“Lady beetle larvae ate quite a few, but the adults weren’t interested,” Ruberson said.
“We do have some native predators that like to eat the nymphs, but we need to find out what they will do in the field. These species are all generalists. They may move back and forth between types of insects and not provide consistent control.”
(The kudzu bug is a definite threat to Southeast soybeans and recently has been implicated in international trade. For that story, see Kudzu bug now interfering with Southeast exports. For a recent update on the threat to soybeans in the Southeast, see http://southeastfarmpress.com/markets/kudzu-bug-now-interfering-southeast-exports).