Imagine being able to ask your fiddle leaf fig why its leaves are turning brown and crispy, or checking in with your apple tree about the best day to harvest. While it sounds like something out of Little Shop of Horrors, communicating with plants is actually far less science fiction than you might think.
Researchers from Nanyang Technological University, Singapore, devised a tool that can deliver electrical signals to and from plants, allowing a path for communication. The device, detailed in two separate papers in Nature Electronics and Advanced Materials, won't quite let you speak to your sunflowers, but it can monitor how the plant responds to its environment, and transmit movement instructions to the plant.
In order to achieve this feat, the researchers had to figure out how to measure the electrical signals emitted by plants. Normally, electrical stimulation is done through electrodes, but they couldn't be utilized in this case since the plant's hairy and bumpy surface made it difficult for electrodes to stay attached. To tackle this problem, the researchers developed a gel-like "morphable" electrode that could attach to the surface of the plant.
The Venus flytrap experiments
When the morphable electrode was tested on a Venus flytrap, it successfully relayed the signals the plant was emitting. But the researchers didn't stop there and experimented with actually "talking" with the plant.
They were successful in getting the plant to close its leaves on demand when they pulsed a specific frequency through the electrode. In a previous study published in Nature Electronics, the researchers were also able to attach the Venus flytrap to a robotic arm and command it to close and pick up a piece of wire.
"The device can now stick to more types of plant surfaces, and more securely so, marking an important step forward in the field of plant electrophysiology," said co-lead author of the Advanced Materials study Professor Loh Xian Jun in a statement. "It opens up new opportunities for plant-based technologies."
What are the possible applications?
The researchers hope that their work will help with active crop monitoring devices that could help to combat food insecurity due to climate change.
"By monitoring the plants' electrical signals, we may be able to detect possible distress signals and abnormalities," said lead author Professor Chen Xiaodong. "When used for agriculture [purpose], farmers may find out when a disease is in progress, even before full‑blown symptoms appear on the crops, such as yellowed leaves. This may provide us the opportunity to act quickly to maximize crop yield for the population."
Moreover, this technology could have applications in robotics. Scientists could make plant-based robots that could gently pick up fragile objects.
You can watch the video below to see the electrode in action: