The Influence of Nickel and Copper Salts on Seed Germination of Native and Alien Species of Bidens (Asteraceae) from Populations of the Upper and Middle Volga

Abstract

The influence of nickel and copper salts on seed germination of the native species Bidens tripartita L. and the alien species B. frondosa L. growing in geographically remote populations was studied in the laboratory conditions. It was shown that the seeds of the alien species were more resistant to the action of heavy metals than the native seeds. Perhaps, this was due to the higher biomass of B. frondosa seedlings, which, along with other indices, indicated a high adaptability of the species to extreme conditions, ensuring its successful expansion. We observed differences in germination of B. tripartita seeds from the Upper and Middle Volga populations influenced by nickel and copper salts at concentrations of 50 mg/L and 1, 50, and 100 mg/L, respectively. Copper was found to have the greatest toxic effect on seed germination at concentrations of 50–100 mg/L.