Non-invasive, quantitative and repetitive imaging of photoassimilate flow after source and sink manipulations

ポジトロンイメージング技術を用いた非侵襲的かつ定量的な炭素動態の解析

鈴井 伸郎; 河地 有木; 石井 里美; 中村 進一*; 石岡 典子; 藤巻 秀

Suzui, Nobuo; Kawachi, Naoki; Ishii, Satomi; Nakamura, Shinichi*; Ishioka, Noriko; Fujimaki, Shu

Higher plants regulate photoassimilate flow from source to sink organ in order to respond to environmental or developmental changes. An understanding of the source-sink interrelationship requires an experimental system which can measure the change of phothoassimilate flow corresponding to various conditions in source and sink organ. In this study, we adapted C-tracer and the positron emitting tracer imaging system (PETIS), which can obtain carbon dynamics in intact plants non-invasively and quantitatively. To manipulate the conditions in source and sink organ, we treated leaves or roots of plants (rice and soybean) with p-chlorobenzenesulfonic acid (PCMBS), an inhibitor of sucrose transporters. CO was supplied to leaves after PCMBS treatments and the translocations of C-photoassimilates were monitored using PETIS repetitively with the same plants. We have developed an analytical method to estimate the velocity of C-photoassimilate flow from PETIS data. As a result, a gradual change in the velocity after PCMBS treatments was successfully detected. The effect of source/sink strength on the velocity of photoassimilate flow was discussed.