抄録
The behavior of 14C from radioactive waste in paddy rice (Oryza sativa L.) at different stages of plant development was studied using the hydroponic and acetic acid as 14C-source. For 14C-application, plant root was soaked for 2 hours in a nutrient solution containing 14C-acetic acid at the vegetative growth stage (Aug. 2, 2007), heading (flowering) stage (Aug. 30, 2007) and milk-ripe stage (Sep. 13, 2007). In final sampling day (Mar. 5, 2008), 0.88-1.96% of the applied radioactivity was recovered from whole plant, however, the ratio of recovered radioactivity was not different at the growth stage. The distribution of 14C absorbed at each stage to each organ was noted to be highest in the submersed root through all the stages. Therefore the mixing of the root residue at the time of plowing would result in enhancement of the soil persistence of 14C.
