Design and Development of an Instrumentation System to Detect the Bioelectric Signals of Plants

Bioelectric potential is generated in a plant by its physiological activities. Therefore, evaluation and monitoring of the plant activities can be done by measuring the changes in its bioelectric potential. The objective of this project was to develop a suitable instrumentation system that magnifies the plant bioelectric signals which are read at the surface of a leaf using a copper needle electrode. Further, it will also help in understanding the physiological behavior of plants which in turn may enable farmers to cultivate the plant crops in a more effective way. Copper needle electrodes were used as they are less susceptible to movement and also have less impendences compared to surface electrodes. Bioelectric potentials of the Bryophyllum plant were measured using copper needle electrodes. Bioelectric signal was amplified by an instrumentation amplifier (AD 620) and then converted to digital signal using a Data Acquisition device (DAQ) and monitored on a Cathode Ray Oscilloscope (CRO).