Hardware and software system for studying bioimpedance characteristics of plant tissues using impedance spectroscopy

Abstract

The development and experimental validation of a hardware and software system designed to study the electrical properties of plant tissues using bioimpedance spectroscopy is discussed. The system hardware is based on a specialized AD5933 impedance converter and is supplemented with external analog components to improve the stability of the measurement signal. The software provides automated measurement control, scanning parameter settings, system calibration, and data processing and visualization. Experimental studies were conducted on weed stems (sow thistle) in the frequency range of 10–100 kHz. The measurements revealed a pronounced frequency dependence of the impedance modulus manifested as β-dispersion due to the capacitive properties of cell membranes and their influence on the distribution of electrical current in the tissue. It was shown that with increasing frequency, impedance decreases due to a decrease in membrane reactance and an increase in the contribution of intracellular conductivity. An additional analysis of the Cole-Cole hodographs revealed deviations in the experimental curves from the idealized semicircle. This deviation was found to be due to the influence of electrode polarization which was particularly pronounced when using a two-electrode measurement scheme. The practical significance of this study lies in the applicability of the proposed approach for the rapid monitoring of plant physiological conditions in laboratory and field conditions. The obtained results confirm the sensitivity of bioimpedance spectroscopy to the physiological state of plant tissues. The developed hardware and software system may be used for rapid diagnostics of plant conditions and is also of practical interest for phytomonitoring and applied research in agrobiophysics.