Bioaccumulation of Al, Mn, Zn and Cd in pea plants [Pisum sativum L.] against a background of unconventional binding agents

This article studies the effect of Aln, sodium humate, and sodium silicate on metal solubility and their bioaccumulation in pea plants. Research was carried out in 1997 using water cultures. There were three series of quick 2-week tests of plant reactions towards Zn2+, Cd2+ (series I), Al3+ (series II) and Mn2+ (series III) added in the form of soluble salts into modified Knopp's substrate. The toxic amounts of Zn and Cd were added into the basic substrate in a form of soluble nitrate. Toxic quantities of Al and Mn were added into the substrate in a form of soluble salts: A1C13 • 6H2O and MnSO4 • H2O, respectively. Sodium humate, AI13 or both preparates were added into some objects to study zinc and cadmium immobilization (series I). Sodium silicate (IV), humic acid (Aldrich) or both were added into some objects in order to differentiate aluminum and manganese contents in the environment (series II and III). Accumulation coefficients calculated for Zn and Cd showed that zinc presence in the substrate inhibited cadmium accumulation in the plant. Cadmium was easily accumulated in over-ground parts. Zinc was released due to Ali3 with humic acid presence and then it accumulated in roots. Silicon compound, especially along with humic acid presence, was the factor determining the mobilization or immobilization of Al and Mn in the environment and thus it affected the yields of plants under study.