Water–Ion–Solute Interrelations and the Integral Water Transport System

Dear Colleagues,

Water transport in plants has historically been considered a passive process. With the discovery of aquaporins and Steudle's Compound Theory, a model was established in which physical and osmotic forces were considered to work in parallel. With the advances in molecular biology, the complexity of mechanisms that encompass water transport in plants began to be elucidated; however, new questions arose: How does water circulate against the gradient? How can cavitation problems be solved? Is there active ion–water coupling in energetically unfavorable situations? By contrast, the transport of ions and nutrients has been extensively studied, but it is essential to understand in depth the interactions between the transport of these compounds and water movement. Water, ion, and nutrient transporters are regulated in common ways in different situations, and aquaporins have a pivotal function. The interactions between xylem and phloem in the regulation of conductance are a pathway that has not yet been sufficiently explored. Finally, the influence of symbiotic organisms in these processes should be taken into account. The nature of water transport in plants needs to be seen as a global system. In this Topic, we will attempt to unite the knowledge that brings us closer to a better understanding of the water integral transport system at the whole plant level.

Dr. Gloria Bárzana
Dr. Monica Calvo Polanco
Topic Editors