EN
The ever-increasing environmental pollution necessitates organisms to develop specific defense systems in order to survive and function effectively. Lead is taken up by plants mainly through roots and over 96% are accumulated there.Pea plants were cultivated hydroponically for 4 days with 0.1, 0.5 and 1 mM Pb(NO3)2. Uptake of lead ions from nutrient solution and accumulation in root stems and leaves during 96-h cultivation was estimated. The root tip cells were observed with transmission electron microscope to analyse their ultrastructure and lead localization. Pb was accumulated in the cell wall, cell membrane, vacuoles, mitochondria and peroxisomes. The fractions of mitochondria and peroxisomes were isolated from pea roots purified by means Percoll gradient, and were observed by means of electron microscope with the attachment for X-ray microanalysis. Visible deposits containing Pb were observed in both cell organelles.