Abstract:To study the effects of physiological and biochemical characteristics and growth under water stress,we potted Liyu 18 seedlings under four different soil content levels:optimal water content (CK),mild water stress (LS),moderate water stress (MS) and severe water stress (SS),which were controlled by weighing the soil and pots.The results showed that:(1)With the increase of stress level,the maize biomass was significantly reduced,while root shoot ratio,root activity,proline content were increased.The influence of water stress on above-ground part was more than that of root.Soluble protein content was not significantly different and MDA content fluctuated.(2)Along with the period of water stress continued,root shoot ratio,root activity and proline content were increased and then decreased;soluble protein of roots was declined and then increased.MDA accumulation fluctuated in seedling of maize and MDA content in leaf were higher than that in root.(3)In preliminary stress,CAT was more sensitive than SOD and POD in leaf;root in moderate water stress mainly depends on CAT to reduce oxidation damage,while it also depends on CAT in severe water stress early and then through the CAT and POD common action to reduce the oxidation damage.POD synchronously reduced oxidation damage in leaf and root,while the complementary role existed between SOD and CAT in leaf and root.We can conclude that the growth of maize seedlings were negatively influenced by different degree of drought stress,but the protective enzyme system and osmatic adjustment substance could adjust themselves to avoid water drought harms.