It might be tiny, but the sweetpotato whitefly (Bemisia tabaci) is an agricultural pest that packs a punch. It's even attained notoriety as one of the 100 worst invasive species on the planet. The sweetpotato whitefly sinks its mouthparts into more than 900 host plants, sucking out their sap and dribbling a sticky excretion called honeydew onto leaves. That sugary residue attracts sooty mold, a fungal disease that can inhibit photosynthesis. Plus, the whitefly transmits 111 known viruses to the plants it feeds on, some of which result in substantial crop losses. If that weren't bad enough, whiteflies are now resistant to many pesticides.

That's why a team of researchers in Japan developed a pest suction machine optimized for whiteflies on greenhouse tomatoes, as described in a study published in May in the Journal of Economic Entomology. They say the device—which combines LED lights, ultrasonic devices, and a powerful suction unit—has potential as an alternative pest control method when used as part of an integrated pest management strategy.

"In Japan, agricultural products are expected to have a beautiful appearance," Saito says. "Therefore, a method was required to get the whiteflies to fly away without damaging the tomato leaves, but this was difficult. At that time, I heard a presentation by Ms. [Chihiro] Urairi, one of the co-authors, who was researching ultrasonic focusing devices. I thought that this might be able to generate vibrations and make whiteflies fly away without touching the tomatoes, so I decided to do research with her. In this way, the idea for the pest suction machine was born."

That machine comprises a battery-powered, computerized traveling cart with onboard suction and ultrasonic devices. Whiteflies are attracted to green light, so the team installed a green LED flashlight aimed at the tomato plants and a rope of green LEDs looped around the suction port. The idea is to vibrate the pests off the leaves and entice them toward the light where they're pulled in and captured on internal sticky plates.