Effect of Environmental Factors on Cd Accumulation of Tagetes erecta L

A hydroponic culture experiment was conducted to study the effect of temperature and nutrient level on Cd accumulation in Tagetes erecta L.. In the first experiment, shoot Cd accumulation and transpiration rate at different temperature was determined. Cd accumulation was lower with higher transpiration rate at 35°C than that of 25°C or 15°C with lower transpiration rate. In the other experiment, cadmium accumulation of plants varies significantly under the condition of different nutrient supplication. Contents of Cd in roots were not high, but the contents of Cd in shoots were the highest when plants were cultivated in 0.05-fold Hoagland’s solution. Roots Cd accumulation decreased as the concentration of single nutrient element (N, P, S) decrease or absence, and shoots Cd accumulation decrease in the condition of sulfur deficiency and sulfur absence. It was shown that transpiration is not the primary factor affecting Cd accumulation in Tagetes erecta L, but growth rate of plants has certain correlation with Cd accumulation; contents of Cd in roots are most affected by the supplication of nutrient elements, yet shoots accumulation is relatively lagging behind; different nutrient element has some different effect on Cd accumulation, and the effects of nitrogen and sulfur on the shoots Cd accumulation are the greatest.