兰坪铅锌尾矿区根瘤菌对铅锌响应研究

Study on the Response to Lead and Zinc of Rhizobia Isolated from Lanping Lead-Zinc Mining Tailings

以从兰坪铅锌尾矿区已分离纯化的10株豆科植物根瘤菌为研究对象,用含50～1 500 mg/L的铅、200～2 000 mg/L的锌的单盐YMA培养基和双盐培养基进行培养,观察根瘤菌的生长情况,筛选出3株耐(抗)铅锌菌株,分别为菌株14.2.9、18.2.17、3.2.3。结合生理生化指标的测定结果,发现耐性强的菌株对各种糖利用特征与其他菌有所不同,能产酸而不产气;分解利用油脂、淀粉、明胶等物质的能力高于耐性弱的根瘤菌。说明在兰坪尾矿区根瘤菌存在多种生理类型,很可能通过改变代谢途径适应重金属污染的环境。

The cell growth of 10 rhizobia of leguminous plants isolated from Lanping lead-zinc（Pb-Zn） mining tailings were observed on YMA culture plates adding 50～1 500 mg/L Pb2＋,200～2 000 mg/L Zn2＋ or disalt.Three strains,3.2.3,14.2.9 and 18.2.17 were screened out as Pb-Zn high resistance rhizobium strains.The detection results of physiological and biochemical properties showed that carbohydrate fermentation pathways of strain 14.2.9,18.2.17,3.2.3 were different from the Pb-Zn low resistace strains,these 3 rhizobia fermented to produce sour instead of gas,and they had high ability of hydrolyzing lipin,starch and gelatine et al.The results confirmed that rhizobia in Lanping Pb-Zn mining tailings had abundant physiological and biochemical diversity.The adaption of rhizobia to the Pb-Zn pollution was probably resulted from the change of their metabolic pathway.