Premium
Salt stress reduces root water uptake in barley ( Hordeum vulgare L.) through modification of the transcellular transport path
Author(s) -
Knipfer Thorsten,
Danjou Mathieu,
Vionne Charles,
Fricke Wieland
Publication year - 2021
Publication title -
plant, cell and environment
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.646
H-Index - 200
eISSN - 1365-3040
pISSN - 0140-7791
DOI - 10.1111/pce.13936
Subject(s) - apoplast , hordeum vulgare , endodermis , water transport , transcellular , hydraulic conductivity , xylem , aquaporin , botany , water flow , chemistry , seedling , biophysics , horticulture , cell wall , biology , soil science , poaceae , biochemistry , soil water , environmental science
The aim of the study was to understand the hydraulic response to salt stress of the root system of the comparatively salt‐tolerant crop barley ( Hordeum vulgare L.). We focused on the transcellular path of water movement across the root cylinder that involves the crossing of membranes. This path allows for selective water uptake, while excluding salt ions. Hydroponically grown plants were exposed to 100 mM NaCl for 5–7 days and analysed when 15–17 days old. A range of complementary and novel approaches was used to determine hydraulic conductivity (Lp). This included analyses at cell, root and plant level and modelling of water flow. Apoplastic barrier formation and gene expression level of aquaporins (AQPs) was analysed. Salt stress reduced the Lp of root system through reducing water flow along the transcellular path. This involved changes in the activity and gene expression level of AQPs. Modelling of root‐Lp showed that the reduction in root‐Lp did not require added hydraulic resistances through apoplastic barriers at the endodermis. The bulk of data points to a near‐perfect semi‐permeability of roots of control plants (solute reflection coefficient σ ~1.0). Roots of salt‐stressed plants are almost as semi‐permeable (σ > 0.8).