Abstract:With Sedum spectabile Boreau as material,by simulating the heavy metal cadmium(Cd) pollution,we detected the Cd accumulation in plant and the best tolerance on Cd(NO3)2 concentration by using atomic absorption spectrometry and Colorimetric methods.Based on the above research results,Under 100 μmol·L-1 Cd(NO3)2 treatment,morphological response were observed and Cd content in each group of its root were compared by using Semi thin section,scanning electron microscopy(sem) and X-ray spectroscopy.The results show that:(1)After Cd(NO3)2 stress.The distribution of Cd in different organs was uneven,Specifically,root>stem>leaf.(2)Under less than or equal to 100 μmol·L-1 Cd(NO3)2 treatment,S.spectabile Boreau can take days of normal physiological metabolism.When Cd(NO3)2 concentration reaches to 400 μmol·L-1,S.spectabile Boreau apparent Cd poisoning,as severe of membranous of root were badly damaged.(3)The surface of roots of sedum spectalile Boreau occured Shrinkage,Root hair markedly increased,difficult to distinguish outer epidermis and cortex,with more parenchyma cells layers than that of control group,closely packed and inregular.(4)After 100 μmol·L-1 Cd(NO3)2 stress,the distribution of Cd in different tissues was uneven,Specifically,root>stem>leaf.In conclusion,S.spectabile Boreau can tolerate a high concentration of Cd(NO3)2 and has the potential research value for Cd pollution soil repairing.
