中文摘要：

通过旱棚人工控水，以元宝枫的生长阶段作为因素，采用三元二次通用旋转组合设计，对元宝枫不同生长阶段下供水量与供水方式对叶片中超氧化物歧化酶（SOD）活性的影响进行了研究。结果表明，均恒供水条件下，当土壤相对含水率低于87．849／6时，SOD酶活性随土壤含水量的增大而增大。当土壤相对含水率超过87．849／5时，生长前期SOD酶活性随含水量的增高而增大，在生长盛期和生长后期则随土壤含水量的增高而降低。元宝枫生长期中，SOD酶活性在生长盛期有所升高，在生长后期酶活性有所下降。谐变供水条件下，幼树叶片中超氧化物歧化酶活性随年均土壤供水能力和幼树各生长阶段供水模式的不同而变化。在单一阶段土壤相对含水率不超过87．84％时，幼树sOD酶活性随生长前期和生长后期随供水量的增大而增大；在单一阶段土壤相对含水率超过87．84％时，幼树叶片中SOD活性在中前期一生长前期和生长盛期随供水量的增加而增大。在土壤供水能力基本相同时，不同生长阶段供水量的分配对元宝枫幼树SOD活性有较大影响。综合分析表明，生长前期供水与SOD活性呈正相关，生长后期和生长中期供水量与SOD活性呈负相关。

英文摘要：

Using the artificial water control technique in the shed of free-rain and periodically changing water supply at different growth stages during annual growth period, we examined the SOD activity in leaves of Acer truncaturn youngling to water stress . The results showed that the SOD activity was affected by the average amount and procedure of water supply at different growth stages over the annual growth period. The SOD activity of A. truncaturn youngling increased with increasing water supply at the early growth stage and the late growth stage when the relative soil moisture was no more than 87.84% at any growth stage. When the relative soil moisture was more than 87.84% at any single growth stage, the SOD activity of A. truncatum youngling increased with increasing water supply at the early growth stage and fast growing stage . The apportionment of water supply among growth stages had a big impact on the SOD activity, showing the highest sensitivity of A. truncaturn to soil water stress at the early growth stage.