Watching Carbon Dioxide Move in Plant Leaves


U.S. Department of Energy (DOE) plant biology research seeks to optimize plant productivity, both for biofuel development and for carbon sequestration in biomass. Taking a lesson from medical technology, plant biologists are now using sophisticated imaging technology to learn more about nutrient utilization in plants by watching the movement of those nutrients in real time. Positron emission tomography (PET) imaging has been used to study carbon transport in live plants using 11CO2, but because plants typically have very thin leaves, littlemedium is availablefor the emitted positronsto undergo an annihilation event within the plant leaf resulting in limited sensitivity for PET imaging.To address this problem DOE’s Thomas Jefferson Laboratory has developed a compact beta-positive, beta-minus particle imager (PhytoBeta imager) for 11CO2 leaf imaging. The detector is equipped with a flexible arm to allow its placement on or under a leaf while maintaining its original orientation. The detector has been used to generate dynamic images of carbon translocation in a leaf of the spicebush (Lindera benzoin) under two transient light conditions. The PhytoBeta detector system and methodology opens new possibilities for short-lived radioisotope use in plant biology research,especially for problems relatedto carbon utilization, transport, and sequestration.


Weisenberger, A. G., B. Kross, S. Lee, J. McKisson, J. E. McKisson, W. Xi, C. Zorn, C. D. Reid, C. R. Howell, A. S. Crowell, L. Cumberbatch, B. Fallin, A. Stolin, and M. F. Smith. 2012. “PhytoBeta Imager: A Positron Imager for Plant Biology,” Physics in Medicine and Biology 57(13), 4195–210. DOI: 10.1088/0031-9155/57/13/4195.