title: Correlation of foliar MT2b expression with Cd and Zn concentrations in hybrid aspen (Populus tremulaxtremuloides) grown in contaminated soil.
abstract: Metal uptake and its effect on foliar metallothionein 2b (MT2b) mRNA levels were studied in hybrid aspen (Populus tremulaxtremuloides) in field conditions. The trees were planted on a site contaminated with several metals, including cadmium (mean 5.1 mgkg(-1)), chromium (80 mgkg(-1)), copper (180 mgkg(-1)), nickel (81 mgkg(-1)), vanadium (240 mgkg(-1)) and zinc (520 mgkg(-1)). Of the ten trace elements analyzed, only Cd and Zn accumulated in the leaves with maximal foliar concentrations of 35 and 2400 mgkg(-1) (dry weight), respectively. There was a strong correlation between Cd and Zn concentrations and bioaccumulation factors (concentration in plant/soil) in the leaves, branches and roots, suggesting similar transport mechanisms for these two metals. The levels of MT2b correlated with Cd and Zn concentrations in the leaves, demonstrating that increased MT2b expression is one of the responses of hybrid aspen to chronic metal exposure.
authors.affiliation: North Savo Regional Environment Centre, Kuopio, Finland; Department of Biosciences, University of Kuopio, Finland.
authors.forename: Viivi
authors.initials: V
authors.lastname: Hassinen
authors.forename: Veli-Matti
authors.initials: VM
authors.lastname: Vallinkoski
authors.forename: Sari
authors.initials: S
authors.lastname: Issakainen
authors.forename: Arja
authors.initials: A
authors.lastname: Tervahauta
authors.forename: Sirpa
authors.initials: S
authors.lastname: Kärenlampi
authors.forename: Kristina
authors.initials: K
authors.lastname: Servomaa
mesh_terms: D001673:Biodegradation, Environmental; D002104:Cadmium / Q000032:analysis*; D003300:Copper / Q000032:analysis; D054750:Ecotoxicology / Q000379:methods; D008668:Metallothionein / Q000032:analysis*; D009532:Nickel / Q000032:analysis; D018515:Plant Leaves / Q000737:chemistry*; D018517:Plant Roots / Q000737:chemistry; D032107:Populus / Q000378:metabolism*; D012989:Soil Pollutants / Q000032:analysis*; D015032:Zinc / Q000032:analysis*
chemical_list: D012989:Soil Pollutants; D002104:Cadmium; D003300:Copper; D009532:Nickel; D008668:Metallothionein; D015032:Zinc