Developing an Acquisition System to Sutdy Plant Electrophysiology

Abstract

Plants are constantly tapped to the environment in order to maintain homeostasis, synchronising internal functions to external phenomena. There is great interest in advancing in the field of plant electrophysiology so as to employ plants as biosensors in the future. A custom-made acquisition system to study plant electrophysiology was developed, including a three channel signal conditioning circuit and ADC with dynamic sampling rate. Also, air temperature and humidity, soil temperature and humidity and irradiance are monitored. To test the system an experiment was conduced to study lettuce, Batavia Amari Paris, response to acid. For this two groups of 4 lettuce each, one used as control the other subject to fertilising treatment, were studied in the absence of stimuli and in response to acid deposition. Feature selection was made using discrete wavelet analysis. The fertilised lettuce showed little response to acid, but fairly strong correlations between signals in the leaf zone. Control group showed high incidence of high frequency fast transients in response to acid, especially in the root zone. Both groups showed higher variance of DC values during day time than night time.