The fact that plants emit barely perceptible electrical signals to sense and respond to their environments has been known for decades. And yet, due to the weakness of those signals, as well as the difficulty of achieving reliable transmission due to the irregular surfaces of many plants, harnessing that power has been a real challenge.
Now, however, researchers from the Nanyang Technological University, Singapore (NTU Singapore) have devised a method that allows them to “communicate” with a Venus flytrap – a carnivorous plant that lures insects into its hairy leaf-lobes – and even make it perform certain actions.
The NTU team behind the pioneering method that allows researchers to interface with plants via electrical signals and control their movements on demand. Image courtesy of the Nanyang Technological University
Results were published in the journal Nature Electronics.
The feat was achieved by attaching a small piece of conductive material (3 mm in diameter) to the surface of the plant using a sticky hydrogel. This allowed the researches to monitor how the plant responds to its environment, and transmit electrical signals through a smartphone to make it close its leaves on demand, in 1.3 seconds.
Further improvements to the system could enable the development of highly sensitive plant-based robotic systems capable of picking up and moving extremely small and fragile objects. The potential for such applications was demonstrated by causing the plant to pick up a piece of wire half a millimetre in diameter.
In addition, the system could be used to monitor plants’ responses to the environment and predict the development of diseases in advance, which could help farmers protect their crops and reduce the chances of bad yields, improving food security for their respective communities.
“By monitoring the plants’ electrical signals, we may be able to detect possible distress signals and abnormalities. When used for agricultural purposes, 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 maximise crop yield for the population,” said lead author Chen Xiaodong.
In a separate study published in the journal Advanced Materials, researchers have also used a different type of hydrogel called thermogel to enhance signal transmission and reduce background noise. At room temperature, thermogel changes from a liquid to a stretchable gel, thereby allowing for better adherence to plants with different surface textures.
Up next, the NTU team is planning to continue work on their new “communication” device and find other practical applications that could be used in a wide variety of fields.