Cell expansion rate, temperature and turgor pressure in growing leaves of <i>Lolium temulentum</i> L.

Abstract

SUMMARY Leaf growth rate and the turgor pressure of cells in the expanding zone of leaves of Lolium temulentum were measured simultaneously. Growth rate was reduced over a range from 30μm min −1 to zero by reducing the temperature of the expanding zone from 20 to 2 °C. Turgor pressure remained constant at 05 MPa. This implies that growth reduction by low temperature is due to changes in cell wall rheology. Cell membrane hydraulic conductivity (L p ) was reduced with temperature as expected, but this was not sufficient to influence growth rate detectably.