S12 - Session P3 - System interpreting electrophysiology networks in agricultural crops: the water case

Authors: Daniel Tran *, Gil Carron, Sandra Anselmo, Elena Najdenovska, Fabien Dutoit, Marco Mazza, Laura Elena Raileanu, Nigel Wallbridge, Carrol Plummer, Cédric Camps

Living organisms have evolved complex signaling networks to drive appropriate physiological processes in response to changing environmental conditions. Amongst them, electric signals are a universal method to rapidly transmit information, called electrophysiology. Recent studies have shown that water status can be assessed on tomatoes growing under typical production conditions with an electrophysiological biosensor combined with supervised machine learning algorithms. The objective of the present study is to determine the ability to apply electrophysiology based diagnostic algorithms for a wider range of agricultural crops of interest in Switzerland. The specific effect of drought was investigated to ascertain whether drought signals were similar across different species. To this end, we conducted experiments on indoor crops namely basil, eggplants, cucumber, as well as on outdoor crops with raspberry and vines under water deficit conditions. The effect of drought was investigated by continuously recording electrical signals. In addition, different key physiological attributes were monitored such as stomatal conductance, transpiration, and chlorophyll and photosynthesis efficiency. The obtained findings show that photosynthesis related factors displayed a lower efficiency in response to water deficit in all tested crops. The photosynthesis as well as substrate humidity were correlated to daily bioelectrical variations. These latter showed a modification (baseline, amplitude) as previously described on tomatoes. In addition, preliminary models built with machine learning techniques showed good classification performance. Deeper analysis and further refinement of the models are required to better understand and decipher common signal features between each crop. Crop electrophysiology could help improve understanding of plant signaling in response to drought that would in turn allow electrophysiology to be used as an agronomic tool to support precision irrigation.