人参红皮病与土壤生态条件的关系

Relationship between the genesis of ginseng rust spots and soil ecological conditions

采用生态样块方法，研究了白浆土区不同地貌生态条件对人参红皮病的影响。结果表明，床土中还原物质浓度随地貌类型而变化，其中活性有机质与参根病情指数相关性最高，成为人参红皮病发生的主要因素；铁的富集是人参红皮病的主要特征，锰为次要因素；周皮铁主要为络合物，包括活性亚铁、活性高铁和非活性铁，它们相互转化，视土壤水分状况为转移；Ｆｅｏ／Ｆｅｄ 与活性有机质相关显著，表明无定形铁是锈斑铁的主要来源；床土通气性高，持水孔度也高，表明床土中氧化过程和还原过程同时进行，对促进土壤中铁的转化具有重要意义。

This paper deals with the ecological relationship between the condition of Ginseng rust spots,the reducing substances in the bed soil and the epidermis iron forms of Ginseng roots within the albic soil region of Jilin lava platform.The results showed that the concentrtion of reducing substances varied in different relief units.The active organic matter was markedly related to the illness index and become the major factor in the genesis of Ginseng rust spots.The enrichment of iron played the first important role in the epidermises of Ginseng roots.The epidermis iron was mainly composed of the organic complexing matter including active ferrous and ferric forms,and non active ferric forms,and they were transformed into each other with the change of soil moisture and temperature regime.The Fe o/Fe d was related to the active organic matter,that implied that amorphous iron in the soil might be the major source of Ginseng epidermis iron.The capacity of air filled pores was higher and the capacity of water holding pores also higher in the bed soil.It suggested that the oxidation reduction process in the soil to be tested happened at the same time,and it was of important significance for the transformation of iron in the bed soil.