The effect of heavy metal salt anions on their toxicity to higher aquatic plants

Abstract

The toxic effects of nickel and copper salts with different anions were compared at the initial stages of the ontogenesis of Bidens cernua. No toxicity limits of the studied salts for the seed germination have been found, which suggested a high resistance of this species to the effect of HM in comparison with other representatives of aquatic plants. It has been shown that acetates of both metals are more toxic than chlorides for seed germination at high concentrations (500–1000 mg∙L-1), as evidenced by a significant decrease in laboratory germination. For the seedling growth, nickel acetate was more toxic than its chloride, as evidenced by a significantly shorter main root and hypocotyl comparing to control. Meantime, copper chloride turned out to be more toxic than copper acetate, which was observed for the development of seedlings. The study indicated the need to take into account anions when comparing the effects of HM salts on plants during the experiments.

Keywords

• nickel
• copper
• chloride
• acetate
• seed germination
• seedling development
• bidens cernua