Cadmium adsorption and accumulation by Ceratophyllum demersum L.: A fresh water macrophyte

G.P. Kumar, M.N.V. Prasad*

Department of Plant Sciences, University of Hyderabad, Hyderabad, 500046, India

Received 17 November 2002; accepted 15 December 2003


Ceratophyllum demersum (aquatic macrophyte, popularly known as coontail) plants were treated with cadmium viz., 2.5, 5.0, 7.5 and 10.0mM for a duration of 2, 4, 6 and 8 days to examine the amount of Cd adsorbed and accumulated from the hydroponic system. In all treatments, Cd adsorbed to the plant decreased with increasing treatment duration. Whereas, at a chosen treatment of duration, Cd adsorbed to the plant increased with increasing treatment concentration. On the other hand, Cd accumulation increased with increasing treatment concentration as well as duration. Cd adsorption as well as accumulation was found to be significantly correlated with the treatment duration at all tested concentrations. However, adsorption showed negative correlation with the treatment duration. Significant differences were noticed between the concentrations and treatment periods for adsorption as well as accumulation of the Cd. After 2 days treatment at 2.5mM concentration, Cd present in the hydroponic medium was found to be negligible. In plants treated for second time with the same Cd concentration after washing the plants with 10mM EDTA solution for 5 minutes, Cd adsorption was not observed. EDTA pretreatment prevented the adsorption, and increased Cd accumulation. Based on the present study it can be concluded that C. demersum is suitable plant to remediate Cd polluted effluents. EDTA pretreatment would enhance the accumulation of the Cd.

Keywords: Adsorption; Accumulation; Cadmium; Ceratophyllum demersum

* Corresponding author
   E-mail : mnvsl@uohyd.ernet.in