Effect of Citric Acid Content in Soil Planted with Panax Notoginseng on Soil Lead(Pb)Morphology and Plant Resistance
Soils planted with Panax notoginseng for 1(T1),2(T2),3(T3)and 8(T4)years were used to investigate the effects of citric acid content in soils planted with Panax notoginseng on soil Pb morphology and Panax notoginseng plant resistance.As the number of years of Panax notoginseng cultivation increased,the citric acid content of soil increased,the acid-extractable Pb content of soil in-creased significantly with the increase of citric acid content,the reduced Pb content decreased with the increase of citric acid concentration,and the oxidized and residual Pb contents of CK were significantly higher than those of T4 and T3 treatments.T4 treatment of Panax notoginseng had the highest Pb content in roots,stems and leaves,and its enrichment coefficients of roots,stems and leaves were sig-nificantly higher than those of other treatments.The activities of SOD,POD and CAT in Panax notog-inseng roots,stems and leaves increased significantly with the increase of citric acid concentration.