Close up of a brown marmorated stink bug on a leaf

The brown marmorated stink bug, a common pest both on farms and inside homes, can be detected through trace amounts of its DNA left on plants. Credit: George Grall/National Geographic/Getty

Ecology

Stink bugs leave DNA footprints on produce

Genetic detection is much more sensitive than conventional traps.

Stink bugs leave a DNA trail that can help scientists to detect the pest’s forays into crop fields.

The brown marmorated stink bug (Halyomorpha halys) is native to Asia, but has damaged crops across North America and Europe. Rafael Valentin at Rutgers University in New Brunswick, New Jersey, and his colleagues developed a highly sensitive method for detecting the insect. The researchers gathered DNA from the surface of fruits and vegetables by sampling water used to rinse harvested crops. Any DNA was concentrated on a filter, which was then analysed for the invasive stink bug’s genetic signature.

This method allowed the authors to verify the insect’s presence at a peach orchard known to be infested. The team also used the technique to detect the bug on each of eight days of testing at a vegetable farm that was not previously known to be infested. By comparison, conventional traps at the farm caught only one brown marmorated stink bug during the same period.

The system could help farmers to track agricultural infestations more efficiently, the authors say.