Plasma membrane and cell wall properties of an aspen hybrid (Populus tremula × tremuloides) parenchyma cells under the influence of salt stress

Abstract

The effect of salinity on cell turgor, plasma membrane permeability and cell wall elasticity has been measured in petioles of an aspen hybrid using the cell pressure probe. Control plants were grown in soil without the addition of NaCl and treated plants were grown in soil with 50 mM of NaCl for 1, 2, 3 and 4 weeks. In parenchyma cells from Populus tremula 9 tremuloides petioles with an increased level of NaCl in the soil: (a) turgor pressure was reduced after 1 week of treatment but afterward it was similar to untreated plants, (b) the value of elastic modulus of the cell walls increased, and (c) hydraulic conductivity of the plasma membrane of treated plants decreased in comparison to untreated ones. No histological differences and distribution of JIM5 antibody between the petioles of plants grown under salinity and the untreated were found. In cell walls of parenchyma and collenchyma from plants grown under salinity, the presence of pectic epitopes recognized by JIM7 antibodies was increased in comparison to the control plants. The obtained results indicate that under salt stress the permeability of water through plasma membrane is disturbed, cell walls became more rigid but the turgor pressure did not change.