A research team led by Mark Hoddle, a biological control specialist at UC Riverside, has nearly eradicated the glassy-winged sharpshooter, a major agricultural pest, from the island of Tahiti and several other French Polynesian islands in the South Pacific Ocean.
To achieve total pest suppression, the researchers used biological control, an inexpensive method that provides permanent control and can be applied to areas where the sharpshooter has become a nuisance.
The method involves introducing Gonatocerus ashmeadi, a microscopic parasitic wasp, into an ecosystem under siege from the glassy-winged sharpshooter. The tiny stingless wasp attacks glassy-winged sharpshooter eggs by drilling a tiny hole in the egg through which the parasite lays its own egg. The wasp larva that hatches from the egg then eats the inside of the glassy-winged sharpshooter egg, killing it. The wasp larva completes its development inside the host egg and then emerges as a tiny winged parasite that searches for more glassy-winged sharpshooter eggs to kill.
“We had the technology to do the job cheaply and in a way that brought about permanent control of the glassy-winged sharpshooter in Tahiti and its neighboring islands,” said Hoddle, an extension specialist in the Department of Entomology and the director of the Center for Invasive Species Research. “When biological control – the use of a pest’s natural enemies to keep the pest’s population growth in check – works, it is very effective and safe in most cases. The parasites spread naturally and on their own, and they fly, requiring little, if any, continuous human assistance over a wide geographic area.”