采用土柱栽培与大田试验相结合的方法 ,研究了 2 0世纪 5 0年代以来我国主要推广玉米品种 (Zea mays L.)根系抗氧化保护酶活性的演进特性。研究表明 :随玉米品种更替 ,根系 SOD、CAT、POD等保护酶活性提高 ,膜脂过氧化产物 MDA含量降低 ,玉米品种更替的过程伴随根系清除活性氧的能力增强、衰老缓慢。当代品种根系 SOD、CAT活性在生育后期下降缓慢 ,显著高于 1970 s和 195 0 s品种 ,下层根系尤为明显。MDA含量则随生育进程的推进呈递增趋势 ,前期增加缓慢 ,后期增加迅速 ,上层根系高于中层和下层根系 ,生育前期品种间 MDA含量差异不显著 ,生育后期195 0 s品种显著高于 1970 s、 1990 s品种。当代品种具有更强的活性氧清除能力 ,后期膜脂过氧化伤害轻 ,有利于维持根系在产量形成期维持较强的生理活性 Using the combination of soil-column cultivation and field experiments, the evolution characteristics of antioxidant enzyme activity in the roots of maize (Zea mays L.), a major popularized maize variety in China since the 1950s, were studied. The results showed that the activities of SOD, CAT, POD and other protective enzymes in the roots were increased and MDA content in membrane lipid peroxidation products decreased with the replacement of maize varieties. The turnover of maize varieties was accompanied by the ability of roots to scavenge reactive oxygen species and slow aging. The activities of SOD and CAT in the roots of contemporary cultivars decreased slowly during the later growth period, significantly higher than those of 1970s and 195 0s, especially in the lower roots. MDA content showed an increasing trend with the progress of growth and development, with a slow increase in the early stage and a rapid increase in the late stage. The root system in the upper layer was higher than that in the middle layer and the lower layer. There was no significant difference in the MDA content between the pre-growing varieties and 195 0 s in the late growing period , 1990 s variety. Contemporary cultivars have stronger ability to scavenge reactive oxygen species (ROS), and have less damage to membrane lipid peroxidation in the late stage, which helps maintain the physiological activity of the root system at the stage of yield formation