11C-Autoradiographs to Image Phloem Loading

Frontiers in Forests and Global Change

Adeline Fayolle¹  Anaïs Pasiphaé Gorel¹  Olivier Leroux²  Kathy Steppe³  Jackie Epila³  Michiel Hubeau³  Stefaan Vandenberghe⁴  Jens Mincke⁴  Christian Vanhove⁴ 

[1] Agro-Bio Tech Department Biosystem Engineering (BIOSE), University of Liege, Gembloux, Belgium;Department of Biology, Faculty of Sciences, Ghent University, Ghent, Belgium;Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium;Medical Imaging and Signal Processing-Innovative Flemish in-vivo Imaging Technology, Department of Electronics and Information Systems, Faculty of Engineering and Architecture, Ghent University, Ghent, Belgium;

关键词: autoradiography;    carbon-11 (11C);    phloem loading;    carbon distribution;    Populus tremula L.;    Erythrophleum spp.;   

DOI  :  10.3389/ffgc.2019.00020

来源: DOAJ

【 摘 要 】

Generally, tree species load photoassimilates passively into the phloem, while herbaceous species load actively. These phloem loading strategies have implications for phloem sugar concentration and growth potential. Whereas, in previous research, phloem loading identification was performed with 14C-autoradiography, we suggest 11C-autoradiography, because of its compatibility with plant-PET (positron emission tomography) scans. Because 11C-autoradiography has been hardly used in plant sciences so far, it was tested in contrasting plant species: one temperate tree species, Populus tremula L., three tropical tree species, Erythrophleum suaveolens (Guill. & Perr.) Brenan, E. ivorense A. Chev., and Maesopsis eminii Engl., and two herbaceous crop species Solanum lycopersicum L. and S. tuberosum L. Our results confirmed that P. tremula is a passive loader, and Solanum spp. are active loaders. Erythrophleum spp. and young leaves of M. eminii showed the expected passive loading strategy, but the mature leaves of M. eminii showed an uncommon pattern. Images corrected for leaf tissue thickness supported that mature leaves of M. eminii used active phloem loading, which is linked to continuous investment in growth and new leaves, supporting the lower carbon storage levels often observed in tropical tree species. With this study, we demonstrate that 11C-autoradiography is a powerful tool to acquire detailed tracer distribution in leaves to typify phloem loading strategies in plant species.

【 授权许可】

Unknown