Modulation of cadmium uptake and toxicity in Spirodela polyrrhiza (L.) schleiden due to malathion.

Fronds of Spirodela polyrrhiza were treated with different concentrations of Cd and malathion singly and in combinations. Results showed that Cd toxicity was more than malathion. The chlorophyll content was more severely affected by Cd (EC-50 of >1.0 µg ml(-1)); however, its toxicity was ameliorated in the presence of malathion (EC-50 of 2.0 µg ml(-1)). Although biomass and frond numbers were least affected by these toxicants, at initial treatment durations fronds multiplication was more severely affected than biomass with an increase in treatment durations. The importance of these findings have been discussed in relation to metal abatement and biomonitoring.