title: Analysis of Triticum aestivum seedling response to the excess of zinc.
abstract: The effects of 50 and 300 mg L(-1) Zn(2+) (50 Zn and 300 Zn) were investigated in Triticum aestivum (cv. Żura) grown hydroponically for 7 days. Although wheat treated with 50 Zn took up relatively high amount of the metal (8,943 and 1,503 mg kg(-1) DW in roots and shoots, respectively), none of the morphological and cytological parameters were changed. After 300 Zn, the metal concentration increased to 32,205 and 5,553 mg kg(-1) DW in roots and shoots, respectively. It was connected with the depletion of shoot and root growth, their fresh and dry weight, water content and mitotic index of root meristematic cells. Microelement contents (Cu, Mn and Fe) after 50 Zn were changed only in roots, while 300 Zn disturbed ion balance in whole plants. The most evident ultrastructural alterations of root meristematic cells caused by both tested Zn(2+) doses included increased vacuolization, accumulation of granular deposits inside vacuoles and cell wall thickening. The effect of 300 Zn on root cell ultrastructure was greater that of 50 Zn. The majority of mitochondria had condensed matrix and swollen cristae, plastids contained plastoglobuli, nucleoli were ring-shaped, thinned down cytoplasm with lipid droplets and swollen endoplasmic reticulum cisternae appeared. In mesophyll cells, 50 Zn caused slight reorganization of chloroplast thylakoids and formation of condensed mitochondria. Three hundred Zn triggered more extensive, but not degenerative, changes: plasmolysis of some cells; chloroplasts with protrusions, changed thylakoid organisation and often large starch grains; irregular, condensed mitochondria. The results indicate that T. aestivum cv. Żura is relatively tolerant to Zn stress.
authors.affiliation: Laboratory of Microscopy Imaging and Advanced Biological Technics, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237, Lodz, Poland. slawa@biol.uni.lodz.pl.
authors.forename: Sława
authors.initials: S
authors.lastname: Glińska
authors.affiliation: Laboratory of Microscopy Imaging and Advanced Biological Technics, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237, Lodz, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Gapińska
authors.affiliation: Laboratory of Microscopy Imaging and Advanced Biological Technics, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237, Lodz, Poland.
authors.forename: Sylwia
authors.initials: S
authors.lastname: Michlewska
authors.affiliation: Institute of General and Ecological Chemistry, Lodz University of Technology, Żeromskiego 116, 90-924, Lodz, Poland.
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Skiba
authors.affiliation: Institute of General and Ecological Chemistry, Lodz University of Technology, Żeromskiego 116, 90-924, Lodz, Poland.
authors.forename: Jakub
authors.initials: J
authors.lastname: Kubicki
mesh_terms: D018519:Meristem / Q000187:drug effects / Q000254:growth & development / Q000648:ultrastructure; D008938:Mitosis / Q000187:drug effects; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000648:ultrastructure; D036226:Seedlings / Q000187:drug effects* / Q000254:growth & development / Q000648:ultrastructure; D014908:Triticum / Q000187:drug effects* / Q000254:growth & development / Q000648:ultrastructure; D014617:Vacuoles / Q000187:drug effects; D014874:Water Pollutants, Chemical / Q000494:pharmacology*; D015032:Zinc / Q000494:pharmacology*
chemical_list: D014874:Water Pollutants, Chemical; D015032:Zinc
keywords: Growth parameters; Microelement content; Mitotic index; Ultrastructure; Wheat; Zinc toxicity