title: The essential oil secretory structures of Prostanthera ovalifolia (Lamiaceae).
abstract: The structure of the essential oil secretory tissues of Prostanthera ovalifolia R.Br was investigated using bright- and dark-field optical microscopy, and scanning and transmission electron microscopy. The leaves of P. ovalifolia have glandular trichomes of the peltate type common to many Lamiaceae species. The trichomes consist of a basal cell embedded in the epidermis, a stalk cell with heavily cutinized walls and a 16-celled secretory head, but they differ from those of many previously reported Lamiaceae species in their morphological form defined by the elevated cuticle. The sub-cuticular space contains a mixture of lipid and aqueous phases. Secretory cells have dense cytoplasm with many leucoplasts present. Volatile terpenoids are eliminated from the cytoplasm into the sub-cuticular space, the site of essential oil accumulation, via granulocrine secretion.
authors.affiliation: Centre for Biostructural & Biomolecular Research, University of Western Sydney, Richmond, NSW, Australia. p_gersbach@hotmail.com
authors.forename: P V
authors.initials: PV
authors.lastname: Gersbach
mesh_terms: D022081:Cell Surface Extensions / Q000378:metabolism* / Q000648:ultrastructure; D002473:Cell Wall / Q000648:ultrastructure; D019686:Lamiaceae / Q000166:cytology / Q000378:metabolism*; D008563:Membrane Lipids / Q000378:metabolism; D008854:Microscopy, Electron; D009822:Oils, Volatile / Q000378:metabolism*; D019441:Plant Epidermis / Q000166:cytology / Q000378:metabolism; D018515:Plant Leaves / Q000166:cytology / Q000378:metabolism; D013729:Terpenes / Q000378:metabolism
chemical_list: D008563:Membrane Lipids; D009822:Oils, Volatile; D013729:Terpenes; C000521:cutin