title: Ultrastructure of plant leaf cuticles in relation to sample preparation as observed by transmission electron microscopy.
abstract: The leaf cuticular ultrastructure of some plant species has been examined by transmission electron microscopy (TEM) in only few studies. Attending to the different cuticle layers and inner structure, plant cuticles have been grouped into six general morphological types. With the aim of critically examining the effect of cuticle isolation and preparation for TEM analysis on cuticular ultrastructure, adaxial leaf cuticles of blue-gum eucalypt, grey poplar, and European pear were assessed, following a membrane science approach. The embedding and staining protocols affected the ultrastructure of the cuticles analysed. The solubility parameter, surface tension, and contact angles with water of pure Spurr's and LR-White resins were within a similar range. Differences were however estimated for resin : solvent mixtures, since Spurr's resin is combined with acetone and LR-White resin is mixed with ethanol. Given the composite hydrophilic and lipophilic nature of plant cuticles, the particular TEM tissue embedding and staining procedures employed may affect sample ultrastructure and the interpretation of the results in physicochemical and biological terms. It is concluded that tissue preparation procedures may be optimised to facilitate the observation of the micro- and nanostructure of cuticular layers and components with different degrees of polarity and hydrophobicity.
authors.affiliation: Forest Genetics and Ecophysiology Research Group, School of Forest Engineering, Technical University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain.
authors.forename: Paula
authors.initials: P
authors.lastname: Guzmán
authors.affiliation: Forest Genetics and Ecophysiology Research Group, School of Forest Engineering, Technical University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain.
authors.forename: Victoria
authors.initials: V
authors.lastname: Fernández
authors.affiliation: Department of Applied Physics I, Faculty of Physics, University Complutense of Madrid, Avenida Complutense s/n, 28040 Madrid, Spain.
authors.forename: Mohamed
authors.identifier: 0000-0002-5117-2975
authors.initials: M
authors.lastname: Khayet
authors.affiliation: Electron Microscopy National Centre, Faculty of Chemistry, University Complutense of Madrid, Avenida Complutense s/n, 28040 Madrid, Spain.
authors.forename: María Luisa
authors.initials: ML
authors.lastname: García
authors.affiliation: Electron Microscopy National Centre, Faculty of Chemistry, University Complutense of Madrid, Avenida Complutense s/n, 28040 Madrid, Spain.
authors.forename: Agustín
authors.initials: A
authors.lastname: Fernández
authors.affiliation: Forest Genetics and Ecophysiology Research Group, School of Forest Engineering, Technical University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain.
authors.forename: Luis
authors.initials: L
authors.lastname: Gil
mesh_terms: D046529:Microscopy, Electron, Transmission / Q000379:methods*; D019441:Plant Epidermis / Q000648:ultrastructure; D018515:Plant Leaves / Q000648:ultrastructure*; D032107:Populus / Q000648:ultrastructure; D031989:Pyrus / Q000648:ultrastructure