Taking the first cropping soil as the control, effects of the first cropping soil added with Rehmannia glutinosa ( Gaertn.) Libosch. ex Fisch. et C. A. Mey. root and leaf ( with addition of mass ratio 2% and 0 . 5%, respectively ) and its continuous cropping soil on growth and SOD and POD activities in leaf and root of R. glutinosa were researched by pot experiment, and changes in PPO and CAT activities and microbial number in its rhizosphere soil were analyzed. The results show that the growth vigor of R. glutinosa in different treatment groups is consistent with characteristics of field continuous cropping obstacle, all of them appear phenomena of dwarf above-ground part, leaf scorching, root tuber without enlargement, fine main roots, more fibrous roots, dead seedlings and so on compared to the control, in which, inhibition effect of continuous cropping soil on growth of R. glutinosa is the strongest, indicating that root and leaf of R. glutinosa and its continuous cropping soil can inhibit R. glutinosa growth obviously. Fresh and dry weights of root tuber, leaf length, leaf width, crown width and chlorophyll content of R. glutinosa in different treatment groups all are significantly lower than those of the control, SOD activity in leaf and root is higher than that of the control, POD activity is significantly different from that of the control. There are also obvious changes in PPO and CAT activities and microbial number in rhizosphere soil of R. glutinosa in different treatment groups as compared to those of the control, in which, continuous cropping soil can obviously decrease PPO and CAT activities in rhizosphere soil, while the first cropping soil added with root and leaf can lead PPO and CAT activities to increase generally. Number of bacteria in rhizosphere soil of three treatment groups all decrease significantly, those of fungus all increase significantly, while number of actinomycetes increase or decrease but all of them are significantly different from those of the control. According to research results, it is conjectured that root and leaf of R. glutinosa and its continuous cropping soil probably contain some autotoxicity components, as a result, they can cause continuous cropping obstacle of R. glutinosa at a certain degree.%以头茬土为对照，采用盆栽法研究了添加地黄[ Rehmannia glutinosa ( Gaertn.) Libosch. ex Fisch. et C. A. Mey.]根和叶(添加量分别为质量分数2%和0.5%)的头茬土及重茬土对地黄生长及其叶和根中SOD和POD活性的影响，并分析了其根际土壤中PPO和CAT活性以及微生物数量的变化。结果表明：各处理组地黄的长势与田间连作障碍特征表现一致，与对照组相比，均呈现地上部矮小、叶片枯黄、块根不膨大、主根细、须根多、死苗等现象，其中重茬土对地黄生长的抑制作用最强，说明地黄根和叶及重茬土可明显抑制地黄生长。各处理组地黄的块根鲜质量和干质量、叶长、叶宽、冠幅和叶绿素含量均显著低于对照，叶和根中的SOD活性高于对照、POD活性与对照有显著差异。各处理组地黄根际土壤的PPO和CAT活性以及微生物数量也较对照有明显变化，其中重茬土可显著降低根际土壤中的PPO和CAT活性，而添加根和叶的头茬土则可使根际土壤中的PPO和CAT活性总体上升高；3个处理组根际土壤的细菌数量均显著减少、真菌数量均显著增加，而放线菌数量或增加或减少但均与对照有显著差异。根据研究结果推测：地黄的根和叶以及重茬土中可能含有一定的自毒作用成分，可导致一定程度的地黄连作障碍。
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