Effect of selenite and selenate on plant uptake and translocation of mercury by tomato (Lycopersicum esculentum)

Pot culture experiments containing sand and soil, at two levels of mercury (2 and 5 g mL^-1) added through irrigation with increasing supplementation of selenium (selenite and selenate) led to a decrease in the uptake of mercury by tomato (Lycopersicum esculentum) plant. Both the forms of selenium (selenite and selenate) were found to be equally effective in reducing the mercury accumulation by plants. The observed reduction pattern of mercury accumulation in plant tissues has been discussed on the basis of the formation of insoluble HgSe complex in soil-root environment.