title: Growth response of the duckweed Lemna gibba L. to copper and nickel phytoaccumulation.
abstract: To assess the tolerance and phytoaccumulation ability of the duckweed Lemna gibba L. to copper (Cu) and nickel (Ni), the plants were exposed to different concentrations of Cu and Ni (0.1-2.0 mg/l) under laboratory conditions. The results showed that Cu and Ni were tolerated by L. gibba at concentrations ≤0.3 and ≤0.5 mg/l, respectively. However, plant growth decreased by 50% (I(50)) when the medium contained 0.45 mg Cu/l or 0.75 mg Ni/l. The observed LCI (lowest concentration causing complete inhibition) were 0.5 and 1.0 mg/l respectively in the presence of Cu and Ni. Results from metal analysis in plant biomass revealed a high accumulation of Cu (1.5 mg g(-1) DW), a low accumulation of Ni (0.5 mg g(-1) DW) within the plants and a corresponding decrease of metals in the water. The removal percentage of Cu was about 60-80%. We conclude that the duckweed L. gibba L. showed a higher accumulation potential for Cu from polluted water than Ni after 4 days of exposure.
authors.affiliation: Laboratory of Environmental Engineering, Faculty of Engineering, Badji Mokhtar University, PO Box 12, 23000 Annaba, Algeria. khellafdaas@yahoo.fr
authors.forename: Nabila
authors.initials: N
authors.lastname: Khellaf
authors.forename: Mostefa
authors.initials: M
authors.lastname: Zerdaoui
mesh_terms: D029064:Araceae / Q000187:drug effects* / Q000254:growth & development; D018533:Biomass; D003300:Copper / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D009532:Nickel / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical; D003300:Copper; D009532:Nickel