Direct and in situ observations of plants under various light illumination conditions using electrochemical impedance spectroscopy

The possibility of using electrochemical impedance spectroscopy (EIS) for direct and real-time monitoring of plants was investigated. Since EIS is an in situ monitoring technique and the obtained signals tend to reflect the ions in plant cells and tissues, it can be used to observe the ion fluctuations that result from the changes in the lighting conditions. Changes in EIS signals and the fitted parameters were observed upon application of an external stimulation to a Marchantia polymorpha individual, which has been known to cause the movement of calcium ions in cellular tissues. In addition, the EIS signals and fitted parameters also changed by altering the lighting conditions. Although further investigation is required, these fundamental experiments indicate that EIS could be applied to monitor in situ ionic phenomena that occur in plants.