| In order to understand the physiological response mechanism of corn(Zea mays L) seedlings to different wind speeds, changes on MDA content, membrane permeability, protective enzymes activities and osmotic regulation substances contents with 0 (CK), 9, 15 m·s-1 and 18 m·s-1 wind speed treatments were studied during the spring 2013 in the Horqin sand land of Inner Mongolia. The results showed that with the increase of wind speed, plant height, stem diameter and above-ground biomass were decreased by 4.48%, 11.28% and 13.23%, respectively, with 18 m·s-1 treatment from those with the CK treatment. There were not significant differences in MDA contents between the wind treatments and the CK, but membrane permeability with the wind treatments was significant higher than that with the CK, increased by 84.36% and 116.62% from the CK under 15 m·s-1 and 18 m·s-1 treatments, respectively. Activities of SOD, POD and CAT were elevated with the increase of wind strength, reaching additional increases of 37.45%, 94.65% and 82.14% by the 18 m·s-1 treatment from the CK, respectively. Soluble sugar contents became increased significantly and proline contents went decreased by wind strength, resulting in an increase of 31.48% in soluble sugar and a decrease of 40.26% in proline from the CK by the 18 m·s-1 treatment. The results suggested that although increase of wind strength did not cause significant membrane lipid peroxidation in corn seedling, it posed a significant damage of the membrane permeability. The synchronous increases of the SOD, POD and CAT activities implied that these protective enzymes played important roles in prevent lipid peroxidation and protections of cell membrane. Additionally, soluble sugar might play an effective role in osmotic adjustment to wind stress. |