An evaluation of methods for preparing easily damaged cuticular surfaces of plants for scanning electron microscopy

Abstract

SUMMARY Techniques were tested to ascertain the best method for preparing the surfaces of delicate plant cuticles for microscopic examination at magnifications not exceeding 10,000. Using scanning electron microscopy, comparative examinations were made of cuticles of fresh material, ambient dried, freeze dried, critical point dried, and frozen material kept at low temperature. Micrographs were compared with material examined using light microscopy which acted as a control at low magnification. Cuticles of the leaves of runner bean, Coleus and the petals of Nicotiana, showed best surface preservation and least wrinkling when frozen, held at low temperature, and examined on a cryostage.

Comparison of hexamethyldisilazane (HMDS), Peldri II, and critical‐point drying methods for scanning electron microscopy of biological specimens

“…Previous studies (Eveling and McCall, 1983;Hardy et al, 1992;Sargent, 1983) have shown that the delicate bloom of epicuticular wax coatings on leaf surfaces can only be properly preserved by freezing specimens and examining them in the frozen state using a cryostage. Even freeze drying results in alteration of the wax structures due to distortion of the underlying cell wall and cuticle that supports them (Sargent, 1983).…”

Low‐temperature scanning electron microscopy of birch leaves after exposure to ozone

“…With low-temperature SEM (LTSEM) (Echlin, 1978;Marshall, 1987) cellular distortion can be avoided (Beckett & Read, 1986;Muller et al, 1986) and the fine structure of wax components is well preserved (Sargent, 1983;Pitcairn et al, 1986). Therefore, LTSEM has been successfully used for the investigation of plant surfaces (Parsons et al, 1974;Eveling & McCall, 1983;Read & Jeffree, 1991) and surfaces of fracture faces (Beckett & Porter, 1988;Guggenheim et al, 1991) as well as for measurements of stomatal opening (Wright, 1988;Van Gardingen et al, 1989).…”

Scanning electron microscopy preparation methods: their influence on the morphology and fibril formation in Pseudomonas fragi (ATCC 4973)

“…It is generally accepted that cryo-SEM images of hydrated biological specimens represent the most lifelike obtainable (Beckett & Read 1981;Eveling & McCall 1983;Read el al. 1983;Wilson & Robards 1984) despite some apparent inherent loss of resolution.…”