A parasitic wasp, known only by its scientific name Spathius galinae, has been approved by the USDA for release to battle invasive emerald ash borer populations. Photo by USDA/University of Delaware
NEWARK, Del., May 25 (UPI) -- A unique host-specific parasitic wasp -- known only by its scientific name, Spathius galinae -- has been approved for release to battle the invasive emerald ash borer beetle, which has devastated ash tree populations throughout the United States.
The approval came in part thanks to the work of a team of researchers at the University of Delaware, who published a new paper on the wasp this month in the journal Biological Control.
The new research details the impressive hunting techniques of the tiny parasitic wasp.
Finding emerald ash borers isn't easy. As their name says, they bore inside trees. The tiny wasps first locate infested trees by smell, as trees invaded by ash borers give off a unique scent. Next, the wasps walk along the tree trunk until sensors in their legs locate the vibrations of feeding larvae.
The wasps drill through the bark with their ovipositor and lay eggs atop the larvae. The wasp larvae feed on the beetle larvae after they hatch.
Researchers at Delaware conducted a number of experiments involving the wasps in order to determine the ideal temperature for rearing and measure its potential effects on other native insects.
Their tests proved the wasp is highly host-specific and only affected one out of 14 non-target beetles, the gold spotted oak borer -- itself an oak-infesting invader in California.
"Because we have done all these studies, we have developed an effective rearing program and USDA APHIS approved it for release in the United States as of May 2015," researcher Jian Duan, a professor of entomology at Delaware, said in a news release.
"The parasitoid colony has been transferred to USDA-APHIS lab in Brighton, Michigan, where APHIS has a mass rearing facility for all emerald ash borer parasitoids including this one," Duan added. "The plan is, they're going to produce tens of thousands of these parasitoids and send them to northeastern states to release."