As an effect of climate change, several regions of the world are likely to suffer increasingly severe droughts. This will cause increasing stress to urban plants, which are often already affected by pollution, inadequate management and heat island effects. Droughts also pose a threat to food security. It is therefore fundamental to improve technologies and management practices to maximize efficiency in water uses. One possibility is to assess the water status of plants in order to irrigate them based directly on their needs, rather than on predetermined schedules or on proxy environmental variables. A promising technology to this end is to measure and interpret the electric potential (EP) in the vascular bundles. It is indeed well established that plants react to a variety of stimuli, including mechanical damage, burning and sudden air cooling, with specific variations of cells’ membrane potential that propagate across the plant through the vascular bundles and affect the cells’ metabolism. While EP variations associated to disturbance are elicited in response to sudden stimuli, more recent research is trying to detect a variety of stressors, including drought, nutrient deficiency or parasites, based only on a continuous measurement of the EP across time.

In our study we analyzed EP data collected in two drought-stress experiments, on tomatoes and on apricots, respectively. Sixteen statistical features from the time and frequency domains were selected and evaluated on the EP signal. The results show that some time-domain features were significantly different between stressed and control apricots, while other frequency-domain features were significantly different among tomatoes. This preliminary study illustrates the potential value of (i) plant EP data, (ii) the statistical features derivable from those, and (iii) the possibility to develop models for the assessment of plant drought stress as part of management actions in both urban and agricultural systems.