Study On The Mechanism Of Absorption And Accumulation Of Heavy Metal Cd In Roots Of Suaeda Heteroptera

Heavy metal Cd is highly toxic and mobile,and it is a heavy metal that is extremely harmful to the ecological environment.Elements,which have a greater toxic effect on plants and animals.In the repair of heavy metal contaminated soil,phytoremediation has been widely used due to its environmental and economic advantages.The S.heteroptera is a dominant species in the tidal flat wetland in northern China.Plants rely on the root system to obtain various elements from the soil.Therefore,the mechanism of the absorption and accumulation of heavy metal Cd in the roots of the sphagnum can be repaired.Heavy metals contaminate soils provide an important basis.In this paper,under hydroponic,soil culture,the absorption channel of Cd in the roots of S.heteroptera,the absorption kinetics equation of heavy metal Cd in the roots of S.heteroptera,the chemical morphology and subcellular distribution of Cd in the roots of S.heteroptera,the GSH(glutathione),PC(plant chelation state),NPT(non-protein thiol peptide)content in the roots of S.heteroptera were studied,the results are as follows:(1)The absorption of Cd by roots of S.heteroptera was closely related to the calcium and potassium channels in plants,and the absorption of heavy metal Cd by roots of S.heteroptera was mainly through calcium channel;the absorption of heavy metal Cd by roots of S.heteroptera has active absorption;(2)Under hydroponic conditions,the subcellular distribution of heavy metal Cd in the roots of S.heteroptera was mainly cell wall and soluble components.The chemical forms of Cd in the roots of S.heteroptera were mainly extracted with sodium chloride and extracted from acetic acid;(3)Under the soil culture conditions,the content of heavy metal Cd in the roots of S.heteroptera increased with time,and the absorption kinetics of heavy metal Cd in roots of S.heteroptera in accordance with Michaelis-Menten equation;(4)Under the soil culture conditions,the subcellular distribution of heavy metal Cd in the roots of S.heteroptera was mainly cell wall and soluble components.and it was consistent with the distribution under hydroponic conditions,which was related to the tolerance and detoxification mechanism of Cd.Under soil culture conditions,the heavy metal Cd is mainly composed of sodium chloride extraction state,acetic acid extraction state and hydrochloric acid extraction state in the roots of S.heteroptera,which was not consistent with hydroponic conditions.Due to complex environmental conditions,environmental factors can affect the tolerance and detoxification mechanisms of plants;(5)The roots of S.heteroptera had an absorption and accumulation effect on heavy metal Cd,and the content of Cd in the roots of S.heteroptera increased with the increase of concentration and time;NPT,GSH and PC in the roots of S.heteroptera The content of(phytochelatin)increased under the stress of heavy metal Cd,and the sulfhydryl groups in the roots of S.heteroptera increased significantly compared with the control group.