title: Scanning and transmission electron microscopy and X-ray analysisof leaf salt glands of Limoniastrum guyonianum Boiss. under NaCl salinity.
abstract: Leaf salt glands of Limoniastrum guyonianum were examined by scanning and transmission electron microscopes and energy dispersive X-ray analysis (EDAX) system, after growing for three months on sandy soil with or without 300 mM NaCl. Results showed that salt glands were irregularly scattered on both leaf sides and sunk under the epidermal level. Salt excretion occurred in both conditions and is mainly composed of calcium and magnesium in control plants, and essentially sodium and chloride in plants subjected to salt treatment. A salt gland is comprised of collecting, accumulating, and central compartments, and is made up of total thirty-two cells. The collecting cells were characterized by large central vacuoles. Accumulating cells contain numerous, large, and unshaped vacuoles and rudimentary chloroplasts. The central compartment was comprised of four basal cells and each one is surmounted by an apical cell. The basal cells are granulated, containing large nucleus, numerous mitochondria, endoplasmic reticulum, ribosomes, polyribosomes, and small vacuoles or vesicles. Equally, the apical cells are rich in organelles. Application of 300 mM NaCl to the culture medium increased vacuoles number and size, and organelles density especially the mitochondria which suggests energy requirement for ions transport. The reduction in size and number of vacuoles toward the interior of salt glands of treated plants and the fusion of the smallest ones with the plasma membrane substantiate the implication of such vacuoles in salt excretion process. The current study which is the first report on L. guyonianum salt gland has provided an in-depth understanding on structure-function relationship in the multicellular salt glands.
authors.affiliation: Laboratoire des Plantes Extrêmophiles, Centre de Biotechnologie de Borj-Cedria, Université de Tunis El Manar, B.P. 901, Hammam-Lif 2050, Tunisia; King Khalid University, Biology Department, P.O. Box 9004, Abha 61413, Saudi Arabia. Electronic address: barhoumi_zou2000@yahoo.fr.
authors.forename: Barhoumi
authors.initials: B
authors.lastname: Zouhaier
authors.affiliation: Laboratoire des Plantes Extrêmophiles, Centre de Biotechnologie de Borj-Cedria, Université de Tunis El Manar, B.P. 901, Hammam-Lif 2050, Tunisia.
authors.forename: Atia
authors.initials: A
authors.lastname: Abdallah
authors.affiliation: Laboratoire des Plantes Extrêmophiles, Centre de Biotechnologie de Borj-Cedria, Université de Tunis El Manar, B.P. 901, Hammam-Lif 2050, Tunisia.
authors.forename: Trabelsi
authors.initials: T
authors.lastname: Najla
authors.affiliation: Laboratoire des Plantes Extrêmophiles, Centre de Biotechnologie de Borj-Cedria, Université de Tunis El Manar, B.P. 901, Hammam-Lif 2050, Tunisia.
authors.forename: Djebali
authors.initials: D
authors.lastname: Wahbi
authors.affiliation: Unité de Recherche de Biologie et Physiologie Cellulaires Végétales, Département de Biologie, Faculté des Sciences de Tunis, Campus Universitaire, 1060 Tunis, Tunisia.
authors.forename: Chaïbi
authors.initials: C
authors.lastname: Wided
authors.affiliation: Unité de Microscopie Electronique, Faculté de Médecine de Tunis, Avenue Mohamed Karoui, 4002 Tunis, Tunisia.
authors.forename: Ben Ammar
authors.initials: BA
authors.lastname: Aouatef
authors.affiliation: Laboratoire des Plantes Extrêmophiles, Centre de Biotechnologie de Borj-Cedria, Université de Tunis El Manar, B.P. 901, Hammam-Lif 2050, Tunisia.
authors.forename: Abdelly
authors.initials: A
authors.lastname: Chedly
authors.affiliation: Laboratoire des Plantes Extrêmophiles, Centre de Biotechnologie de Borj-Cedria, Université de Tunis El Manar, B.P. 901, Hammam-Lif 2050, Tunisia.
authors.forename: Smaoui
authors.initials: S
authors.lastname: Abderazzak
mesh_terms: D000818:Animals; D002118:Calcium / Q000032:analysis; D004577:Electron Probe Microanalysis; D004721:Endoplasmic Reticulum / Q000648:ultrastructure; D008274:Magnesium / Q000032:analysis; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D008928:Mitochondria / Q000648:ultrastructure; D018515:Plant Leaves / Q000737:chemistry / Q000648:ultrastructure*; D029606:Plumbaginaceae / Q000737:chemistry / Q000648:ultrastructure*; D054712:Salinity; D014965:X-Rays
chemical_list: D008274:Magnesium; D002118:Calcium
keywords: Morphology; Salinity; Salt gland; Ultrastructure; X-ray analysis