Building Bridges: Mycelium Mediated Plant-Plant Electrophysiological Communication

Whether through root secretions or by emitting volatile organic compounds, plant communication has been well-documented. While electrical activity has been documented in plants and mycorrhizal bodies on the individual and ramet, electrical propagation as a means of communication between plants has been hypothesized but understudied. This study aimed to test the hypothesis that plants can communicate with one another electrically via conductively isolated mycelial pathways. We created a bio-electric circuit linking two plants using a mycelial network with a blend of endomycorrhizal fungi grown on potato dextrose agar forming the isolated conductive pathway between plants. Using this plant-fungal biocircuit we assessed electrical propagation between Pisum sativum and Cucumis sativus We found that electrical signals were reliably conducted across the mycelial bridges from one plant to another upon the induction of a wound response. Our findings provide evidence that mechanical input can be communicated between plant species and opens the door to testing how this information can affect plant and fungal physiology. Simple SummaryMost plants form underground relationships with fungi. These relationships are mutually beneficial. The plants and fungi share, trade, and distribute resources between themselves, their neighbors, and their offspring. Plants employ diverse methods to detect and respond to their environment and the production of electric signals is one of these methods. It would be favorable to a plants survival and the survival of their neighbors, if this plant could transmit and share the information these electrical signals contain. Possible avenues of transmission exist in the roots, and the fungi these roots are in contact with. If a fungal mass is in contact with the roots of multiple plants, it could propagate electrical signals throughout the plant network. We found that electric signals were reliably transmitted from one plant to another via fungal pathways upon the induction of a wound response. Our findings provide evidence that mechanical input can be communicated between plant species and opens the door to testing how this information can affect plant physiology.