Spatial patterns of surface electric potential of a root of azuki bean (Phaseolus chrysanthos) were investigated. A multi-electrode measuring system was used to measure the spatial pattern and its variation with time. It was found that a periodic pattern was spontaneously formed along the root but it disappeared under anoxia. Supply of air made the pattern recover. Although the change in electric potential started from the root tip under anoxia, it occurred first near the seed in the recovery process when air was supplied. To explain this phenomenon, a simplified theoretical model was proposed. The model is described by a differential equation for a concentration of oxygen expressing longitudinal diffusion and consumption of oxygen within the root. Assumption of a threshold of the oxygen concentration needed to activate a respiration-dependent pump led to a quantitative explanation of the above behaviour of surface electric potential. It was suggested that the pattern belongs to a group of self-organized dynamic structures which are maintained through energy metabolism by a supply of material from outside.
|Number of pages
|Annals of Botany
|Published - Nov 1988
All Science Journal Classification (ASJC) codes
- Plant Science