Discriminating and continuous measurement of photosynthesis and respiration by monitoring 13CO2 and 12CO2 as tracers

摘要

The simultaneous and discriminative measurement of photosynthesis and respiration of plants was attained by simultaneous monitoring of 13CO2 and 12CO2 by artificial control of 13CO2 volume in air. The measurement principle is based on several physiological processes which are presented. Assuming that respiratory consumption of the new carbon substrate fixed by photosynthesis is negligible during the measurement, the photosynthetic CO2 consumption and the respiratory CO2 production are measurable. The two methods presented were examined and evaluated on measurements of komatsuna [Brassica campestris] and maize, and are thought to have good potential for the advanced study of plant physiology.