Root pressure and beyond: energetically uphill water transport into xylem vessels?

• Published in: Journal of experimental botany Vol. 65; no. 2; pp. 381 - 393
• Main Author: Wegner, Lars H
• Format: Journal Article
• Language: English
• Published: England Oxford University Press [etc.] 01.02.2014; Oxford University Press
• Subjects: Aquaporins; Aquaporins - metabolism; Arabidopsis; Biological Transport; Cell membranes; energy; mammals; metabolism; Models, Biological; OPINION PAPER; Parenchyma; physiology; Plant Roots; Plant Roots - physiology; plasma membrane; Pressure; rice; Root pressure; sap; Secretion; soil solution; solutes; Thermodynamics; transporters; trees; Vascular plants; Water; Water - metabolism; Water pressure; Water transportation; Xylem; Xylem - physiology; xylem vessels; cohesion–tension (CT) theory; reflection coefficient; water co-transport hypothesis; xylem refilling; CCC transporters; embolism repair; water ascent; Aquaporin; root pressure

The thermodynamics of root pressure remains an enigma up to the present day. Water is transported radially into xylem vessels, under some conditions even when the xylem sap is more dilute than the ambient medium (soil solution). It is suggested here that water secretion across the plasma membrane of...