<Note>The Bioelectrical Potentials of Young Woody Plants

Abstract

The microelectrode method was applied to the measurement of bioelectrical potentials in young woody plants. Japanese cedar (Cryptomeria japonica D. Don) and poplar (Populus nigra Linn.) were used in this experiment. The resting potential was about -40 mV in both species. Light affected the potentials of the shoots, petiols and leaves. The potential changes were the most sensitive in the leaves. And this change occured immediately whenever the light turned on/off. After on/off, the potential recovered to the resting potential in a whole plant and a rootless poplar shoot incubated in water, while it did not recover in rootless poplar shoot incubated in 0.25 M sucrose solution. The surrounding light conditions but not the inner rhythm in trees might control the changes.