PLANT BIOPHYSICS - Y. I. Posudin - 2004

II. TRANSPORT PROCESSES IN THE SOIL-PLANT-ATMOSPHERE SYSTEM

11. ELECTRICAL TRANSPORT

11.1. EXCITABILITY OF PLANT CELLS

A common feature of plants is excitability—the capacity of plant Cells, Tissues, and Organs to alter their state and respond to external stimuli. Plants generate electrochemical signals known as action potentials, which are capable of propagating (akin to nerve impulses) throughout the plant Organism. These potentials serve as carriers of information within intra- and extracellular spaces regarding environmental changes [Byrne and Schultz, 1988].

Responses of Plant Tissues and organs to external stimuli can be either local or propagated over long distances throughout the entire plant via plasmodesmata—minute cytoplasmic strands that pass through pores in Cell walls and connect the protoplasts of adjacent cells. The coordination of internal plant processes and their balance with the environment is achieved through the excitability of plant cells. Excitation induced by external Physical and Chemical stimuli is transmitted across the plant. The propagation velocity of this excitation depends on numerous factors, including light and Water regimes, Temperature, Treatment with agrochemicals (herbicides, salts, growth stimulators, etc.), mechanical damage, electromagnetic and gravitational fields, as well as injury caused by insects and animals.