Increased cuticular wax deposition does not change residual foliar transpiration

• Published in: Plant, cell and environment Vol. 45; no. 4; pp. 1157 - 1171
• Main Authors: Grünhofer, Paul, Herzig, Lena, Sent, Sophie, Zeisler‐Diehl, Viktoria V., Schreiber, Lukas
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.04.2022
• Subjects: Acclimatization; amphistomaty; Composition; Cuticular transpiration; Cuticular wax; Dehydration; Detaching; Environmental conditions; environmental growth conditions; Epicuticular wax; ex vitro acclimatisation; Growth conditions; hypostomaty; in vitro tissue culture; leaf development; Leaves; Plant cuticle; Plant Epidermis; Plant Leaves; Plant Transpiration; poplar; Populus canescens; Populus × canescens; residual transpiration; Stomata; Tissue culture; Transpiration; Water; Water loss; Waxes; ex vitro acclimatisation; poplar; environmental growth conditions; amphistomaty; residual transpiration; hypostomaty; cuticular wax; in vitro tissue culture; Populus × canescens; leaf development
• ISSN: 0140-7791; 1365-3040
• DOI: 10.1111/pce.14274

The effect of contrasting environmental growth conditions (in vitro tissue culture, ex vitro acclimatisation, climate chamber, greenhouse and outdoor) on leaf development, cuticular wax composition, and foliar transpiration of detached leaves of the Populus × canescens clone 84 K were investigated. Our results show that total amounts of cuticular wax increased more than 10‐fold when cultivated in different growth conditions, whereas qualitative wax composition did not change. With exception of plants directly taken from tissue culture showing rapid dehydration, rates of water loss (residual foliar transpiration) of intact but detached leaves were constant and independent from growth conditions and thus independent from increasing wax amounts. Since cuticular transpiration measured with isolated astomatous P. × canescens cuticles was identical to residual foliar transpiration rates of detached leaves, our results confirm that cuticular transpiration of P. × canescens leaves can be predicted with high accuracy from residual transpiration of detached leaves after stomatal closure. Our results convincingly show that more than 10‐fold increased wax amounts in P. × canescens cuticles do not lead to decreased rates of residual (cuticular) transpiration.