title: Both trivalent and hexavalent chromium strongly alter in vitro germination and ultrastructure of kiwifruit pollen.
abstract: Due to its widespread industrial use, chromium is considered a dangerous environmental pollutant. It is known to inhibit plant growth and development. The present study provides the first evidence of the toxicity of this metal on the male haploid generation of a higher plant. Both Cr(III) and Cr(VI) species, supplied as CrCl(3) and CrO(3), respectively, exerted a strong dose-dependent inhibitory effect on kiwifruit pollen tube emergence and growth. Cr(III) resulted more effective than Cr(VI) in the 16-75microM interval; moreover, complete inhibition of germination was attained at much lower doses than Cr(VI). Also tube morphology was affected. While the plasma membrane was still undamaged in the large majority of the treated pollen grains, dramatic ultrastructural alterations were induced by chromium including chromatin condensation, swelling of mitochondria, cytoplasmic vacuolization, and perturbed arrangement of endoplasmic reticulum cisternae. Thus, it seems that the impact of the two chromium species on kiwifruit pollen may result in severe compromission of both essential structures and functions of the male gametophyte.
authors.affiliation: Dipartimento di Biologia Evoluzionistica Sperimentale, Università di Bologna, via Irnerio 42, 40126 Bologna, Italy. anna.speranza@unibo.it
authors.forename: Anna
authors.initials: A
authors.lastname: Speranza
authors.forename: Paola
authors.initials: P
authors.lastname: Ferri
authors.forename: Michela
authors.initials: M
authors.lastname: Battistelli
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Falcieri
authors.forename: Rita
authors.initials: R
authors.lastname: Crinelli
authors.forename: Valeria
authors.initials: V
authors.lastname: Scoccianti
mesh_terms: D029042:Actinidia / Q000187:drug effects / Q000254:growth & development / Q000648:ultrastructure; D002712:Chlorides / Q000633:toxicity*; D017608:Chromium Compounds / Q000633:toxicity*; D004785:Environmental Pollutants / Q000633:toxicity*; D018525:Germination / Q000187:drug effects*; D046529:Microscopy, Electron, Transmission; D011058:Pollen / Q000187:drug effects / Q000254:growth & development / Q000648:ultrastructure
chemical_list: D002712:Chlorides; D017608:Chromium Compounds; D004785:Environmental Pollutants; C028801:chromium trioxide; C017133:chromous chloride