title: Automated analysis of three-dimensional xylem networks using high-resolution computed tomography.
abstract: Connections between xylem vessels represent important links in the vascular network, but the complexity of three-dimensional (3D) organization has been difficult to access. This study describes the development of a custom software package called TANAX (Tomography-derived Automated Network Analysis of Xylem) that automatically extracts vessel dimensions and the distribution of intervessel connections from high-resolution computed tomography scans of grapevine (Vitis vinifera) stems, although the method could be applied to other species. Manual and automated analyses of vessel networks yielded similar results, with the automated method generating orders of magnitude more data in a fraction of the time. In 4.5-mm-long internode sections, all vessels and all intervessel connections among 115 vessels were located, and the connections were analyzed for their radial distribution, orientation, and predicted shared wall area. Intervessel connections were more frequent in lateral than in dorsal/ventral zones. The TANAX-reconstructed network, in combination with commercial software, was used to visualize vessel networks in 3D. The 3D volume renderings of vessel networks were freely rotated for observation from any angle, and the 4.5 μm virtual serial sections were capable of being viewed in any plane, revealing aspects of vessel organization not possible with traditional serial sections.
authors.affiliation: Department of Viticulture and Enology, University of California, Davis, CA, USA.
authors.forename: Craig R
authors.initials: CR
authors.lastname: Brodersen
authors.affiliation: Department of Viticulture and Enology, University of California, Davis, CA, USA.|Department of Chemical Engineering and Materials Science, University of California, Davis, CA, USA.
authors.forename: Eric F
authors.initials: EF
authors.lastname: Lee
authors.affiliation: Hawkesbury Institute for the Environment, University of Western Sydney, Sydney, NSW 2753, Australia.
authors.forename: Brendan
authors.initials: B
authors.lastname: Choat
authors.affiliation: Institute of Systematic Botany and Ecology, Ulm University, Ulm, Germany.
authors.forename: Steven
authors.initials: S
authors.lastname: Jansen
authors.affiliation: Department of Chemical Engineering and Materials Science, University of California, Davis, CA, USA.
authors.forename: Ronald J
authors.initials: RJ
authors.lastname: Phillips
authors.affiliation: Department of Plant Science, University of California, Davis, CA, USA.
authors.forename: Kenneth A
authors.initials: KA
authors.lastname: Shackel
authors.affiliation: Department of Viticulture and Enology, University of California, Davis, CA, USA.|USDA-ARS, Crops Pathology and Genetics Research Unit, Davis, CA 95616, USA.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: McElrone
authors.affiliation: Department of Viticulture and Enology, University of California, Davis, CA, USA.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Matthews
mesh_terms: D000465:Algorithms; D001330:Electronic Data Processing / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008855:Microscopy, Electron, Scanning; D018547:Plant Stems / Q000648:ultrastructure; D012984:Software; D014057:Tomography, X-Ray Computed / Q000379:methods*; D027843:Vitis / Q000033:anatomy & histology / Q000166:cytology*; D052584:Xylem / Q000033:anatomy & histology / Q000648:ultrastructure*