Circumnutation and electrical signals

In order to coordinate the growth and development processes of organisms, intercellular signals, including electrical signals, are necessary. Among electrical signals, we distinguish variation potentials typical only for plants and action potentials (APs). Action potentials are typical for animal organisms; they are the basis for the functioning of the nervous system but they also occur in plants. The AP participates in the induction of a very fast trapping movement of the Venus flytrap (Dionaea muscipula) and the lodging of the leaf after touching the mimosa (Mimosa pudica). APs can be triggered by environmental stimuli or occur spontaneously.

Ultradian series of spontaneous action potentials (SAPs)

For the first time, the publications by Stolarz M, Dziubińska H 2017 Acta Physiologiae Plantarum 39: 234 and next: Stolarz M, Dziubińska H 2017 Frontiers in Plant Science 8: 1766 showed that, in addition to the ultradian slow circumnutation rhythm, there is an ultradian, slow rhythm of spontaneous APs. The interval between subsequent spontaneous action potentials is the same as the circumnutation period, i.e. 2-3 hours.

Circumnutation trajectory disturbances and SAPs

The appearance of SAPs is accompanied by disturbance in the circumnutation trajectory, including a change in the direction of circumnutation and "torsion" movements involving rapid twisting of the stem by approx. 2-4 mm on the background of a slow circumnutation movement. The circumnutation disturbances accompanying SAPs are presented in 8 films in the publication: Stolarz M, Dziubińska H (2017). Spontaneous action potentials and circumnutation in Helianthus annuus Acta Physiologiae Plantarum 39: 234.