title: Localisation and quantification of elements within seeds of Cd/Zn hyperaccumulator Thlaspi praecox by micro-PIXE.
abstract: Cd, Zn and Pb accumulation, spatial distribution within seeds and germinating seedlings, and seeds fitness of metal hyperaccumulating Thlaspi praecox were investigated in order to gain more knowledge on plant reproductive success at metal polluted sites. The seeds contained up to 1351 microg g-1 (dry weight) of Cd, 121 microg g-1 of Zn and 17 microg g-1 of Pb. Seed fitness was negatively influenced by seed Cd hyperaccumulation. Nevertheless, the viability of seeds was decreased by maximally 20%, indicating very efficient tolerance of the plant embryos to Cd. Localisation by micro-PIXE revealed preferential storage of most elements in the embryonic axis. Cd and Zn were preferentially localised in the epidermis of cotyledons. The restriction of seed Pb and Zn uptake and hyperaccumulation of Cd, accompanied by partitioning of Cd in the epidermal tissues of cotyledons, may enable the survival of T. praecox embryos and seedlings in Cd polluted environments.
authors.affiliation: Department of Biology, Biotechnical Faculty, University of Ljubljana, Vecna pot 111, SI-1000 Ljubljana, Slovenia.
authors.forename: Katarina
authors.initials: K
authors.lastname: Vogel-Mikus
authors.forename: Paula
authors.initials: P
authors.lastname: Pongrac
authors.forename: Peter
authors.initials: P
authors.lastname: Kump
authors.forename: Marijan
authors.initials: M
authors.lastname: Necemer
authors.forename: Jure
authors.initials: J
authors.lastname: Simcic
authors.forename: Primoz
authors.initials: P
authors.lastname: Pelicon
authors.forename: Milos
authors.initials: M
authors.lastname: Budnar
authors.forename: Bogdan
authors.initials: B
authors.lastname: Povh
authors.forename: Marjana
authors.initials: M
authors.lastname: Regvar
mesh_terms: D001673:Biodegradation, Environmental; D002104:Cadmium / Q000032:analysis; D007220:Industrial Waste; D007854:Lead / Q000032:analysis; D019216:Metals, Heavy / Q000032:analysis*; D036226:Seedlings / Q000737:chemistry; D012639:Seeds / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis*; D013052:Spectrometry, X-Ray Emission / Q000379:methods; D031227:Thlaspi / Q000502:physiology*; D015032:Zinc / Q000032:analysis
chemical_list: D007220:Industrial Waste; D019216:Metals, Heavy; D012989:Soil Pollutants; D002104:Cadmium; D007854:Lead; D015032:Zinc