The Effect Of Heavy Metal Pb On Seed Germination And Seedling Growth Of Achnatherum Splendens (Trin.) Nevskia

The pollution of heavy metals has now become more and more severe. Pb is a kind of contamination which is fargoing, stable, nondegradation and lasting accumulated.So the possible recovery mechanism of plants and the harm and resistance in the heavy metal Pb has become a recent hot research topic. Achnatherum splendens (Trin.) Nevskia as the main experimental material, the main factor of plant resisting heavy metal Pb was analyzed by using paraffin microtome section,transmission electron microscopy (TEM),gel electrophoresis of isozyme, and two-dimensional gel electrophoresis of total protein, it may offer for choosing plant which has strong capability of restore.The results showed that heavy metal Pb seriously inhabited seed germination of Achnatherum splendens (Trin.) Nevskia and affected seedling growth to various certain extents,it was showed that low seedlings, nongreen leaves , shorter root or can't growing.Research indicates that cortex cell was affected by Pb stress ,starch grain accumulated evidently nevertheless.Ultrastructure showed Pb harmed to some organelles such as cell nucleus, mitochondria ,chloroplast.But combination of cell walls and separating of vacuoles relieved the harm of heavy metal,which made physiological activity of Achnatherum splendens (Trin.) Nevskia in a normal condition.Result of determination of some physiological indexes,such as chlorophyll,dissociated proline, malondialdehyde, soluble total sugar and isoenzyme were showed: all of these indexes changed as the concentration of Pb2+ solution increased evidently when the concentration was in 0mg·L-1-200 mg·L-1,each indexes was not changed at the same time.Pb stress restrain the content of chlorophyll of Achnatherum splendens (Trin.) Nevskia.Whereas,the content of dissociated proline elevated with the increased concentration of Pb2+. Malondialdehyde, soluble total sugar elevated with the concentration of Pb2+ solution increased at first, but the content of malondialdehyde and soluble total sugar reducing when the time going and the concentration elevating,then it reaching a utmost limit of their content when the concentration of Pb being 160 mg·g-1.Isoenzyme zymogram analysis showed POD was put into fullplay when the Pb concentration was in 200 mg·L-1.The activity of amylase was the most strong in 160 mg·L-1. The total anti-heavy metal activity of adenosinetriphosphatase has raised.Each enzyme played a great role for resisting Pb stress.The two-dimensional gel electrophoresis result of protein showed three spots disappearing gradually,nine ones disappearing and nine ones appearing in all of these spots.The protein which has low molecular weight palyed a important role for resisting Pb stress.Above results showed the corresponding physiological reacting of Achnatherum splendens (Trin.) Nevskia was appear in the different concentration of Pb2+.The effect and the concentration of Pb and disposal time are interrelated.Virus of plant by heavy metals is harm to the whole cell physiological activity and biochemistry reacting ,also the virus was the synthetized reacting of so many kinds of physiological process.