Fighting Pests With Sound Waves, Not Pesticides

A tiny bug is threatening your morning orange juice.

In Florida, the Asian citrus psyllid, an aphid-size creature that feeds on the stems and leaves of citrus trees, cost the juice business $3.6 billion between 2006 and 2012. The real damage from “citrus greening” comes from bacteria spread by the bug, which causes leaves to turn yellow and kills the tree in a few years.

Researchers are looking into new ways to combat the pests, and one project focuses on sound rather than pesticides to disrupt the insects’ mating habits.

“We’re trying hard to cut down on use of pesticides in orange groves, partly because we are worried they’ll build up resistance to pesticides, and that will make things even worse,” said Richard Mankin, a research entomologist with the U.S. Department of Agriculture. He presented findings on acoustic disruption at the meeting of the American Acoustical Society this week in Jacksonville.

When a male psyllid wants to mate, he alerts a female by sitting on a leaf and buzzing his wings to send vibrations along leaves and branches. To disrupt that activity, the researchers created a device containing a piezoelectric buzzer and a microphone wired to a microcontroller.