Figure 7.

Examples using positron imaging to trace radiolabelled sugars in plants. A) First use of [¹⁸F]FDG imaging in plants.⁸² [¹⁸F]FDG was applied through the leaf of a sorghum plant, which was first translocated to the discrimination center at the base of the shoots, followed by redistribution to roots and young leaves. B) Intra-leaf transportation of [¹⁸F]FDG in tobacco plants.⁸⁴ The leaf petiole and midrib dominated the initial [¹⁸F]FDG uptake, followed by slower distribution into smaller veins determined by physiochemical properties; however, radioactivity was detected at the leaf tip within 30 seconds of [¹⁸F]FDG application. C) [¹⁸F]FDG allocation and metabolism in wounded and methyl-jasmonate-treated rockcress (Arabidopsis).²¹ [¹⁸F]FDG applied to a cut petiole in rockcress was transported to orthostichous (arranged vertically) leaves in control plants, though diverted to wounded and methyl jasmonate-treated (MeJA) leaves in treated plants. The PET imagery in C) was adapted from Nuclear Medicine and Biology, 39(8), Ferrieri AP, Appel H, Ferrieri RA, & Schultz JC. Novel application of 2-[¹⁸F]fluoro-2-deoxy-D-glucose to study plant defenses, 1152-1160, Copyright (2012), with permission from Elsevier.