Abstract
We focused on measurement of the bioelectric potential as a method of evaluating plant activities and supporting effective cultivation. In this study, we researched on the bioelectric potential response due to photochemical reaction and carbon-fixation reaction in the process of photosynthesis. At first, we measured the bioelectric potential when illumination started and stopped, under N2 gas condition for suppressing carbon-fixation reaction and respiration. In the result, amplitude of the potential response related to illumination intensity and wave length. We considered that the amplitude of potential response in N2 condition indicated activity of photochemical reaction. Based on this result, we investigated the potential response in room air condition. If carbon-fixation reaction was deactivated by long dark period, significant potential decrease was observed when illumination started. In contrast, if carbon-fixation reaction kept active during short dark period, potential decrease was slight or none regardless of photosynthetic rate. Therefore, we considered that this potential decrease related to activation of carbon-fixation reaction. Next, we researched on relationship between plant activities and the potential response when illumination stopped. The result shows that amplitude of the response related to illumination intensity and respiration rate. We conclude that plant activities such as photosynthesis can be evaluated in more detail by measurement of the bioelectric potential with applying this study.
