(AFP) Google News 16 Jul 10;
BANGKOK — Thailand is preparing to release a quarter of a million wasps to fight a South American insect that is wreaking havoc on the country's cassava crops, scientists announced Friday.
The tiny parasitic wasps will be unleashed in the northeastern province of Khon Kaen starting from Saturday in an attempt to control the pest outbreak, the International Center for Tropical Agriculture announced.
The invader, the cassava mealybug, sucks sap from the plants and causes them to shrivel, resulting in yield losses as high as 50 percent in the tropical root crop in the affected Thai area.
The first colony of the wasps -- which measure less than two millimetres (0.008 inches) -- was carried by hand from Benin to Bangkok last year for testing and mass rearing.
The Anagyrus lopezi wasp is said to have already shown itself to be a formidable natural enemy of the cassava mealybug in South America and sub-Saharan Africa, injecting their eggs into the mealybugs.
When the eggs hatch, they kill the unsuspecting host from the inside out. Adult females also feed on the host insect. Scientists said the wasps posed no threat to humans, animals, or other insects.
"Applying chemicals on such a large scale would be environmental vandalism," said Tony Bellotti, an entomologist at the not-for-profit centre, which is involved in the project.
"Sending in the wasps is a proven way to kill the cassava mealybugs quickly and effectively. Think of them as a kind of eco-friendly SWAT team."
Scientists are investigating reports that the cassava mealybug has already spread to Cambodia, Burma, Laos and Vietnam. There are fears it will soon reach other parts of Southeast Asia as well.
"It's going to be an international game of cat-and-mouse," Bellotti said. "As the cassava mealybug finds its way to new countries and regions, we can send in the wasps."
