Novel multiscale insights into the composite nature of water transport in roots

Abstract

- MECHA is a novel mathematical model that computes the flow of water through the walls, membranes and plasmodesmata of each individual cell throughout complete root cross-sections, from a minimal set of cell level hydraulic properties and detailed root anatomical descriptions.\n- Using the hydraulic anatomical framework of the Zea mays root reveals that hydraulic principles at the cell and root segment scales, derived independently by Katchalsky and Curran [1967] and Fiscus and Kramer [1975], are fully compatible, irrespective of apoplastic barriers leakiness.\n- The hydraulic anatomy model accurately predicts empirical root radial permeability (kr) from relatively high cell wall hydraulic conductivity and low plasmodesmatal conductance reported in the literature.\n- MECHA brings novel insights into contradictory interpretations of experiments from the literature by quantifying the impact of intercellular spaces, cortical cell permeability and plasmodesmata among others on root kr, and suggests new experiments efficiently addressing questions of root water relations.\n\n\nSymbols