Phytoextraction of Nickel by Selected Ornamental Plants

In the pot experiment the effect of increasing doses of Ni (the control, 25, 50, 75, 150, 300 mg · dm^-3 substrate) on the content of this metal in individual organs of aboveground parts was investigated in three selected species of ornamental plants: Aztec marigold (Tagetes erecta L.), sunflower (Helianthus annus L.) and love-lies-bleeding (Amaranthus caudatus L.). A significant effect of increasing Ni doses on the content of this metal was found in individual organs of selected species. In Tagetes erecta L. and Amaranthus caudatus L. the highest amounts of nickel were accumulated in leaves, while in sunflower growing in the substrate, to which nickel was introduced at 25, 50, 75 and 150 mg·dm^-3, the highest amounts of this metal were accumulated in inflorescences. Among the analyzed species of ornamental plants growing in the substrate with no addition of this metal and in the substrate with an addition of 25 and 50 mg Ni · dm^-3 the highest nickel uptake was observed in Tagetes erecta L. plants. For the substrate with an addition of 75, 150 and 300 mg Ni · dm^-3 the biggest nickel accumulation was recorded in Amaranthus caudatus L.