Abstract
We present water movement in a plant using a positron emitting nuclide, 15O. Because of the extremely short half-life of 15O, water uptake measurement could be performed only for 20 min. However, after an hour, the next experiment was able to perform using the same plant. A soybean or wheat grown after 3 or 4 weeks in water culture was used. After 15O-water was supplied from the root, an imaging plate (IP) was exposed to the plant periodically. In another way, the BGO detectors were set at the stem and the gamma-rays emitted from the nuclide were counted. Through these two kinds of the measurement, using an IP and BGO detector, we found that the water uptake activity of the plant was drastically reduced under high humidity and dark condition and there was a correlation between the uptake amount of water and light intensity.
