Root hydraulics adjustment is governed by a dominant cell-to-cell pathway in Beta vulgaris seedlings exposed to salt stress

VICTORIA VITALI; MOIRA SUTKA; LUCAS OJEDA; RICARDO AROCA; GABRIELA AMODEO.

PLANT SCIENCE

ELSEVIER IRELAND LTD

Lugar: Amsterdam; Año: 2021

0168-9452

Soilsalinity reduces root hydraulic conductivity (Lpr)of several plant species. However, how cellular signaling and roothydraulic properties are linked in plants that can cope with waterrestriction remains unclear. In this work, we exposed thehalotolerant species red beet (Betavulgaris)to increasing concentrations of NaCl to determine the components thatmight be critical to sustaining thecapacityto adjustroot hydraulics. Our strategy was to use both hydraulic and cellularapproaches inhydroponically grown seedlings duringthe first osmotic phase of salt stress.Interestingly, Lprpresented a bimodal profile response apart from the magnitude of theimposed salt stress.As well as Lpr,the PIP2-aquaporin profile follows an unphosphorylated/phosphorylatedpattern when increasing NaCl concentration while PIP1 aquaporinsremain constant. Lpralso shows high sensitivity to cycloheximide. Inlow NaCl concentrations, Lprwas high and 70% of its capacity could be attributed to theCHX-inhibited cell-to-cell pathway.More interestingly, roots can maintain a constant spontaneousexudated flow that is independent of the applied NaCl concentration.In conclusion, Betavulgarisroot hydraulic adjustment completely lies in a dominant cell-to-cellpathway that contributes to satisfying plant water demands.