Functional water flow pathways and hydraulic regulation in the xylem network of Arabidopsis hydraulic regulation of water flows in xylems

Published in Plant and Cell Physiology, 2014.

Park, J.; Hae Koo Kim; Ryu, J.; Ahn, S.; Lee, S.J.; Hwang, I.

In vascular plants, the xylem network constitutes a complex microfluidic system. The relationship between vascular network architecture and functional hydraulic regulation during actual water flow remains unexplored. Here, we developed a method to visualize individual xylem vessels of the three-dimensional xylem network of Arabidopsis thaliana, and to analyze the functional activities of these vessels using synchrotron X-ray computed tomography with hydrophilic gold nanoparticles as flow tracers. We show how the organization of the xylem network changes dynamically throughout the plant, and reveal how the elementary units of this transport system are organized to ensure both long-distance axial water transport and local lateral water transport. Xylem vessels form distinct clusters that operate as functional units and the activity of these units, which determines water flow pathways, is modulated by varying not only the number and size of xylem vessels, but also by altering their interconnectivity and spatial arrangement. Based on these findings, we propose a regulatory model of water transport that ensures hydraulic efficiency and safety.

Arabidopsis thaliana, Gold nanoparticle, Hydraulic regulation, Plant and Cell Physiology, Synchrotron X-ray CT, Water transport, Xylem network

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Copyright © 2018 CIMMYT Web