Physiological Responses of Three Kinds of Street Trees to Acute Stress of Ozone

Abstract

The stress impacts of ozone pollution on the common street trees in tropical cities were investigated in this study. Three kind of common trees(C.camphora, M.indica and F.altissima) in Xiamen were artificial ozone fumigation stressed for 8h, with the ozone concentration of 0.43 mg/m3 and 0.86 mg/m3 respectively, and their physiological index responses were also analyzed. The results showed that the cell membrane permeability and malondialdehyde (MDA) content of leaves increased but chlorophyll content decreased, the contents of proline and soluble sugar content to regulate osmotic potential, while the activity of superoxide dismutase (SOD) was inhibited when 3 kinds of street trees were subjected to acute ozone stress. In addition, the change amplitude of 6 indexes increased with the increment of ozone stress concentration, which can be used as reference indexes for plant ozone resistance. Based on the performance of plants after stressed, the resistance intensity of 3 species of street trees to ozone stress was: M.indica>C. camphora> F.altissima. The results could provide the reference for screening of ozone resistance trees in the tropics.