Response of the callus cells of fir (Abies nordmanniana) to in vitro heavy metal stress

The aim of the presented research was to investigate the effect of three heavy metals - lead, cadmium and copper - on the callus cells of Abies nordmanniana. The toxicity degree and toxicity effect of the selected heavy metals was determined on the embryonic level. On the basis of the spectrometric analyses as well as macroscopic and microscopic observations, this research referred to the accumulation of heavy metals in tissues, assuming that this mechanism is related to the acquisition of tolerance by cells exposed to this type of abiotic stress. Moreover, the effect of the genotype of fir on the cell defence, that is, the induction of tolerance, was analysed. Understanding of the issues related to the heavy metal resistance of plant genotypes in future may contribute to the selection of genotypes of individuals that are more resistant to stress factors, particularly in the multi-directional and rational forest management. The results showed that lead (20 mg l^-1), which proved to be the most toxic amongst the three examined heavy metals, has the most severe negative effects on the tissue of fir trees. Copper (20 mg l^-1) was accumulated for a long time in the cells of fir trees, and it was not degraded or excreted outside the tissues even after three weeks of in vitro culture. Of the three tested genotypes, G14 had the greatest tendency to accumulate each of the examined metals, that is, it appeared to be the least tolerant genotype.