Wasps Used to Control Pests

Despite the fact that Brazil has overtaken the #1 spot for largest consumer of pesticides, the country is also home to a growing biotechnology firm, Bug Agentes Biologicos, or “Bug.” The company has seen growing success as many farmers in Brazil have begun switching over from pesticides in favor of biocontrol.

The latest trend is using wasp eggs. Currently, farmers can put wasp eggs on pieces of cardboard and distribute them throughout the fields. When the eggs hatch, the wasps grow and eventually lay their own eggs—inside those of the sugarcane borer, a moth that feeds on valuable crops during its caterpillar stage. When wasps lay their eggs inside the sugarcane borers’ eggs, it prevents them from hatching.

Bug is currently running trials for “egg-spraying” from planes, similar to the way common pesticides are currently delivered. They hope to have the method perfected later this year. Trichogramma galloi is the breed of wasps currently being mass produced by Bug, and the company recently made its way onto Fast Company magazine’s list of the worlds’ 50 most innovative companies. Forbes even named it one of the top 10 most innovative firms in Brazil.

Biocontrol certainly isn’t a new technique, but Bug’s method of mass-breeding the wasps is. The main concern of biocontrol is introducing invasive species that could damage local wildlife and ecosystems. The wasps used by Bug “are very specific, only multiply in eggs of butterflies and moths, [and do] not cause harm to humans or plants,” says Diogo Rodrigues Carvalho, who runs the firm.

In the past, biocontrol gone wrong has included the introduction of cane toads to Australia in 1935—which resulted in an explosion of the toad population and the harm of the local ecosystem. Similarly, the release of harlequin ladybirds to destroy aphids has also backfired due to the ladybirds’ predatory nature.

“This ladybird is a massive predator that will eat absolutely everything—including itself—so that’s not a sensible biocontrol agent outside the glasshouse,” said Dr. Dick Shaw of CABI. “You have to be extremely careful.”