The Effects of Cr⁶⁺'s Pollution on the Ultrastructure of Hydrocharis dubia and Cell Membrane of H.verticillata,Brasenia schreberi,Trapa bispinosa

The effects of Cr⁶⁺'s pollution on the ultrastructure of Hydrocharis dubia mainly showed:plasmodesmata fractured,nuclei deformed in different ways,chloroplast enlarged,granum disorganized.Relationship between the le-vel of injured cell and cultural concentration was positive.On the Hydrocharis dubia,H.verticillata,Brasenia schreberi,Trapa bispinosa was plasmolysis and black grains emerged between cell wall and cell membrane;physiological test showed:contents of MDA and O₂ were higher than that of control class.