Cadmium uptake and distribution in tomato plants (Lycopersicon esculentum Mill)

Abstract

The growth responses and accumulation of heavy metal cadmium (Cd) was studied in tomato plants. Tomato seedlings were raised in sand-culture and watered with nutrient solution containing cadmium (in the form of CdCl₂) at doses ranging from 0 to 7.12 mM. At low concentrations, there was no marked growth reduction in terms of fresh and dry mass. However, the highest concentration (7.12 mM) of cadmium depressed growth in terms of fresh and dry mass and caused reduction in chlorophyll content. Sodium Dodecyl Sulfate Page Gel Electrophoresis (SDS-PAGE) of proteins showed the expression of low molecular weight proteins (~18, ~30 kDa) in Cd-treated plants when compared to control. Among the different plant parts examined for Cd accumulation, the root tissue showed maximum accumulation. The uptake, distribution and possible implications of cadmium tolerance in tomato plants are discussed.