Researchers at North Carolina State University have invented a new device that plants can “wear” to help growers monitor the health of crops. The “plant patches” are small, flexible rectangles fitted with graphene sensors and nanowires.
Currently, monitoring plants for disease and stress is time consuming and labor intensive. Plant samples must be collected and analyzed in a laboratory. The new sensor can change all of that.
The sensors on the plant patches are coated with sensitive chemicals that allow them to detect volatile organic compounds (VOCs) that plants emit. These emissions are constantly monitored and stored in the prototype, the team has plans to make newer sensors that wirelessly transmit their readings.
The patches were tested on tomato plants looking for both physical stress and late stage blight caused by an infection of the oomycete Phytophthora infestans.
The sensors were quick to pick up VOCs associated with physical stress, registering the damage within three hours depending on how close the sensor was located to the trouble zone.
The detection of blight took a bit longer, with sensors registering it a few days later. “This is not markedly faster than the appearance of visual symptoms of late blight disease,” said study co-author Qingshan Wei.
“However, the monitoring system means growers don’t have to rely on detecting minute visual symptoms. Continuous monitoring would allow growers to identify plant diseases as quickly as possible, helping them limit the spread of the disease.”
The plant patches monitor the levels of 13 different VOCs, which is much more data than is available by traditional methods.
The researchers are now working to develop a newer and better version of a plant patch, improving on their prototype. The scientists note that this is meant as a real world solution, not just something theoretical.
“Our technology monitors VOC emissions from the plant continuously, without harming the plant,” said Wei. “The prototype we’ve demonstrated stores this monitoring data, but future versions will transmit the data wirelessly. What we’ve developed allows growers to identify problems in the field – they wouldn’t have to wait to receive test results from a lab.”
The study is published in the journal Matter.