Cd, Zn, Cu, Pb, Co, Ni phytotoxicity assessment

In this paper, we investigate using of probit analysis for heavy metals (Pb, Cd, Cu, Zn, Co, Ni) toxicity assessment for spring barley (Hordeum vulgare L.) in sod podzolic sandy loam and chernozem soils. Estimation of the heavy metals phytotoxicity by means of PhLD50 value was suggested. The PhLD50 value is a doze of metal in soil that causes 50% reduction of plant biomass (mg·kg-1). According to PhLD50 value, metals can be ranked by the effect on biomass reduction as: Cd>Cu>Ni>Co>Pb>Zn (sod podzolic soil) and Cd>Cu>Ni>Co>Zn>Pb (chernozem soil). Results of the study could be useful indicators of Cu, Ni, Co, Cd, Pb and Zn phytotoxicity assessment at the growing of Hordeum vulgare (L.) in heavy metals contaminated areas. The PhLD50 value demonstrates the comparative toxicity of metals. Tight correlation between studied metals phytotoxicity for plants of spring barley and polarity shift caused by adding to organic matrix – diphenilthiocarbazone (ditizone) for studied metals was observed. This approach may be prominent for metals risk assessment. This work is an attempt to extend our investigations on correlation and methods of polarity assessment and ecotoxicological risk of different groups of contaminants.