摘要:Nickel (Ni) is an essential nutrient for plants and it has been identified as a
component of a number of enzymes such as ureases. In this study, we have studied
the long-term effects of nickel toxicity on black poplar (Populus nigra). The black
poplars were exposed to Ni as NiSO4.6H2O (200, 400, or 800 µM) for 28 days by
using complete randomized design with three replications. In this context, Ni
accumulation and biomass, photosynthetic pigments analyses [chlorophyll a and b
(Chl a and b), carotenoid (Car)], malondialdehyde (MDA) content, antioxidant
enzyme activities [catalase (CAT) and ascorbate peroxidase (APX)], and metallic ion
accumulations were investigated. Ni concentrations significantly increased in root,
bark, and leaves in all Ni treatments. Also, reductions were determined significantly
in the photosynthetic pigments (Chl a, Chl b, Chl a+b, and Car) at all Ni treatments.
The MDA content, CAT and APX activities significantly increased compared the
control plants. According to element analyses, the concentration of metallic ion
accumulations [potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), iron
(Fe), zinc (Zn), manganese (Mn), and copper (Cu)] were affected by Ni exposures,
suggesting that Ni toxicity adversely affects physiological activities in P. nigra.
关键词:phytotoxicity; metallic ion accumulation; heavy metal; plant stress