Functional imaging of photosynthesis in a leafby using carbon-11 labeled carbon dioxide and positron emitting tracer imaging system

C-11標識二酸化炭素を用いたポジトロンイメージング技術による光合成機能画像解析

河地 有木; 鈴井 伸郎; 石井 里美; 石岡 典子; 藤巻 秀

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

The positron-emitting tracer imaging system (PETIS) and caron-11-labeled carbon dioxide (CO) can image carbon movement during photoassimilation and export in a plant leaf, and C kinetics make it possible to estimate physiological function parameters in those processes. With an exposure CO -gas to a leaf, PETIS experiments were performed under three light conditions on a single leaf. In order to estimate the rate constants of photoassimilation parameters, time activity curves of CO gas input and leaf response were fitted to an appropriate compartmental tracer kinetic model, which applies influx and efflux for photoassimilation and photosynthate export rate constants. These results are reasonable response against light environment respectively. Kinetic parameters are fitted enough with pixel-by-pixel analysis, so that our method suggest that a parametric imaging of photosynthesis, which is indicative of a functional-imaging analysis in plant study.