Effects of Damage Stress on Membrane Lipid Peroxidation and Antioxidant Enzymes in Poplar Leaves

The concentration of hydrogen peroxide(H2O2) and malondialdehyde(MDA) and the activities of superoxide dismutase(SOD),catalase(CAT) and peroxidase(POD) were measured in poplar leaves damaged by mechanical damage and herbivore wounding.The results showed that the concentration of H2O2 and MDA and the activities of SOD,CAT and POD were enhanced;the change of membrane lipid peroxidation and antioxidant enzymes was significantly higher in the herbivore wounding treatment(except CAT).The results suggest that the concentration of H2O2 and MDA were closely related to the change in antioxidant enzymes activities.A high level of antioxidant enzymes could decrease membrane lipid peroxidation levels and effectively induce plant defense responses.Meanwhile,the difference between mechanical damage and herbivore wounding suggest that H2O2,SOD,CAT and POD are associated with insect resistance in poplar.