INSTYTUT DENDROLOGII

Two species of poplar (Populus nigra L. and P. deltoides Bartr. ex Marsh) were chosen to investigate the influence of soil contamination with heavy metals on secondary metabolism in fine roots. During heavy metal stress, phenolic compounds can act as metal chelators, they alter peroxidation kinetic by modifying the lipid packing order but they can also directly scavenge molecular species of active oxygen. ln presented work soil from two different stands in the direct neighbourhood of a copper smelter in Głogów, Poland and controlled doses of metals' ions (Cu, Pb, Cd and Zn) were used. Essential differences appeared between the concentration of phenolic compounds in roots and activity of enzymes for the two studied species and for concentration of polluted soil used. These results suggest that oxidative processes were pronounced in P. nigra roots. Thus we conclude that secondary metabolism is stimulated by moderate heavy metals stress and effects of contamination on secondary metabolites are different in these two species. Additionally we assessed potential use of examined poplars for both phytoextraction and phytostabilisation strategies.