Micro-mechanism of damage of soluble lead (Pb2+) on wheat seedlings cells

摘要

Transmission Electron Microscope (TEM) was used to investigate the damage of wheat seedlings by soluble lead and the distribution of Pb2+ in different parts of wheat seedlings was discussed. Experiment showed that Pb pollution caused the damage of root tips cells and lots of abnormal symptoms was observed,including hollowing cytoplasm increasing, disintegration after swelling of the mitochondria cristae, agglutination of chromatin of nucleus, dispersion of nucleolus, disruption of nuclear membrane and even no nucleus. The damage of Pb2+ on wheat leaves was less serious than that of root tips. Pb pollution should lead to swelling of chloroplast and mitochondria and concentration of cytoplasm in leaf cells. It was observed that dark electron dense particles sedimentated in ektexine, extracellular matrix, vacuolar and surrounds the Mitochondrion of root-tip cells. A few electron dense particles were found in ektexine and extracellular matrix of leaf cells.