title: Sunflower exposed to high-intensity microwave-frequency electromagnetic field: electrophysiological response requires a mechanical injury to initiate.
abstract: We have monitored the electrical potential variations (EPV) of sunflower plants illuminated by a high-intensity microwave-frequency (2.5 GHz, 1.5 kV/m) electromagnetic field (EMF). We have designed an appropriate set-up that allows parallel temperature and EPV measurements while part of the plant is being exposed to the field. The results show that the considered EMF does not induce plant EPV directly. This electrophysiological response appears only when the EMF leads to a mechanical injury of the tissues via a thermal effect (dielectric heating). Once the plant inner temperature reached a threshold, we systematically observed burn-like lesions associated with the bending of the stem or leaf-stalks. Theses mechanical constraints were rapidly followed by EPVs, moving through the stem.
authors.affiliation: a Université d'Avignon et des Pays de Vaucluse ; Avignon , France.
authors.forename: David
authors.initials: D
authors.lastname: Roux
authors.forename: Alexandre
authors.initials: A
authors.lastname: Catrain
authors.forename: Sébastien
authors.initials: S
authors.lastname: Lallechere
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Joly
mesh_terms: D055724:Electrophysiological Phenomena / Q000502:physiology*; D006368:Helianthus / Q000528:radiation effects*; D008872:Microwaves / Q000009:adverse effects*; D018515:Plant Leaves / Q000528:radiation effects; D018547:Plant Stems / Q000528:radiation effects; D013694:Temperament
keywords: AP, action potential; EMF, electromagnetic field; EPV, electrical potential variation; SWP, slow wave potential; electromagnetic field; electrophysiology; heat; injury; sunflower