Effect of increased cobalt treatments on cobalt concentration and growth of tomato plants

An experiment developed in soilless culture was used to study the effect of several levels of Co2+ (0, 5, 15, and 30 mg L-1) on the growth of tomato plants (Lycopersicon esculentum M, cv. Ramy). Absorption, transport, and accumulation of this metal in roots, stems, leaves, and fruits were also studied. Uptake was increased by application of this metal concentration in the nutrient solution, efficiency of root uptake of cobalt decreased with increased Co2+ treatment in the soilless culture system. The translocation of Co2+ from roots to aerial vegetative parts was increased with the time of experiment and Co2+ concentration in the nutrient solution. The presence of this metal in nutrient solution reduced tomato leaf production and elongation, specially at higher treatments.