Nickel Phytoremediation Potentialof White Poplar Clones Grown in Vitro

The aim of our study was to examine potentials of different white poplar (Populus alba L.) genotypes to extract nickel in tissue culture. Shoot tips of four clones (Villafranca, L-12, L-80 and LBM) were cultivated on solid growing medium with addition of different nickel concentrations (0, 10^-6, 10^-5, 10^-4 and 10^-3 M) for two different periods: five and seven weeks. Investigated parameters included: length of the longest shoot, biomass production, photosynthetic pigment concentrations in the leaves, nitrate reductase activity and nickel concentration in shoots. The presence of nickel in higher concentration had significant inhibitory effect on accumulation of fresh mass and especially on the photosynthetic pigments content. The presence of nickel in the concentration of 10^-3 M caused serious disturbance of growth and decay in investigated clones. All genotypes significantly increased accumulation of nickel on the medium with 10^-4 M, while on the medium with 10^-5 M Ni²⁺ increase of biomass accumulation was achieved. Obtained results suggest that genotypes L-80 and L-12 could be used in phytoremediation of sites contaminated with nickel in lower concentration.