Abstract:

【Objective】To understand the physiological response of Cyperus esculentus and Glycine max seedlings to wind-blown sand flow.【Methods】In Horqin sandy land in the east of Inner Mongolia Autonomous Region，a portable outdoor sand wind tunnel was utilized to imitate wind-blown sand flow. Four intensities of 0（CK），7，10，and 15 m/s were set to analyse the effects of wind-blown sand flow on the membrane lipid peroxidation，protective enzyme system，and osmotic adjustment substances of Cyperus esculentus and Glycine max seedlings.【Results】Under the stress of wind-blown sand flow，the malondialdehyde（MDA）content in Cyperus esculentus and Glycine max seedlings increased significantly（P<0.05），and membrane lipid peroxidation damage occurred. The activities of superoxide dismutase（SOD），catalase（CAT）and peroxidase（POD）in Cyperus esculentus seedlings were 62.6，62.5 and 27.1 U/g respectively under wind-blown sand flow intensity of 15 m/s，which were significantly increased compared with the intensity of 7 m/s（P<0.05）. The activities of three protective enzymes in Glycine max seedlings had no significant difference between CK and wind-blown sand flow intensity of 15 m/s（P>0.05）. The content of proline（Pro）and soluble sugar in Cyperus esculentus seedlings increased with the increase of wind-blown sand flow intensity. Compared with CK，the content of Pro in Glycine max seedlings increased significantly（P<0.05），while the content of soluble sugar had no significant changes（P>0.05）.【Conclusion】The wind-blown sand flow stress effectively activated the protective enzyme system of Cyperus esculentus seedlings，and played a role in mitigating the membrane lipid peroxidation damage. The protective enzymes of Glycine max seedlings had limited response to wind-blown sand flow stress and did not play a protective role. Pro and soluble sugar together played an osmotic adjustment role in the seedlings of Cyperus esculentus. While in Glycine max seedlings Pro played an important role in osmotic adjustment.

Key words: Wind-blown sand flow, Cyperus esculentus, Glycine max, Membrane lipid peroxidation, Protective enzyme, Osmotic adjustment substances