Plant Electrophysiology with Organic Electronics

Electrical signals in plants are mediators of long-distance signalling and correlate with plant movements and responses to stress. These signals are studied with single surface electrodes that cannot resolve signal propagation and integration, thus impeding their decoding and link to function. We developed a conformable multielectrode array based on organic electronics for large-scale and high-resolution plant electrophysiology. As a model system we studied the generation and propagation of the action potential (AP) in the carnivorous plant Venus flytrap. The AP in VFT is one of the fastest electrical signals in plants and it is generated when the mechanosensitive hairs in the trap are triggered. When two AP are generated within thirty seconds the trap closes. With organic bioelectronics we performed precise spatiotemporal mapping of the action potential in Venus flytrap and found that the AP actively propagates through the tissue with constant speed and without strong directionality. We also found that spontaneously generated APs can originate from unstimulated hairs and that they correlate with trap movement. Last, we demonstrate that the Venus flytrap circuitry can be activated by cells other than the sensory hairs. Our work reveals key properties of the AP and establishes the capacity of organic bioelectronics for resolving electrical signalling in plants contributing to the mechanistic understanding of long-distance responses in plants.