Vapour Pressure Deficit Response of Cuticular Conductance in Intact Leaves ofFagus sylvaticaL.

Publisher Website
Google Scholar
Abstract
The cuticular conductance (gc) of the astomatous adaxial surface of Fagus sylvatica L. leaves was determined under varying vapour pressure deficits at a constant temperature of 20 °C. Cuticular conductance was determined from the weight loss of detached leaves after both the stomatous abaxial surface and the cut end of the petiole had been sealed using low melting-point paraffin wax. Cuticular conductance was found to decrease as the water vapour pressure was increased in steps. No response was observed when vapour pressure deficit was decreased from an initially high value. It is concluded that these results are consistent with the hypothesis that cuticular conductance is influenced by the water content of the cuticle and that the apparent hysteresis is likely to be a result of the long time-constant for the process of cuticle rehydration in intact leaves.