Biologically closed electrical circuits in plants

The Venus flytrap is a marvel of plant bioelectrochemical engineering. The rapid closure of the Venus flytrap upper leaf in about 0.1 s is one of the fastest movements in the plant kingdom. We found earlier that the electrical stimulus between a midrib and a lobe closes the Venus flytrap upper leaf without mechanical stimulation of trigger hairs. Thigmonastic movements in the Venus flytrap, associated with fast responses to environmental stimuli, appear to be regulated through electrical signal transductions. The thigmonastic responses of the Venus flytrap can be considered in three stages: stimulus perception, electrical signal transmission, and induction of mechanical, hydrodynamical and biochemical responses. The hydroelastic curvature mechanism closely describes the kinetics of leaf movements. The electrical properties of the Venus flytrap were investigated and an equivalent electrical circuit was proposed that explains the experimental data.