Objective] The resistant aluminium strains of wild soybean rhizobia in Southern China were screened to set up a system of isolating and identifying aluminum-tolerant rhizobium , and to establish the foundation of effective inoculant for soybean planting areas in South China .[Method]The nodules of wild soybean which grew in Hunan Province and Guangzhou area were isolated by using technique of strains acti -vated culture method .The tolerance of aluminum was detected by spectrophotometer .The growth character-istics of aluminum-tolerant rhizobium were analyzed using the method of inoculation .The effects on growth and nodulation of the cultivated-soybean were explored by inoculating with aluminum-tolerant strains .[Re-sult and conclusion] The results showed that the isolated rhizobium could grow with 200 μmol· L-1 Al3+distinct from the other strains , showing some special features of tolerance to aluminum .The boundary pH that W20 could not survive was 4.0 , while the favorite pH was 6.0 .In the Proton flux assay , W20 had the ability to prevent more H +from penetrating the cytomembrane than W14, which could make W20 a-void some damage caused by H +.Inoculating with the effective rhizobium could significantly increase soybean biomass , nodulation , N content and reduce the content of Al 3+with aluminum addition .The shoot and root biomass of soybean increased by 60.9%and 14.8%respectively , while the nodule num-ber and nodule weight increased by 66%and 209%with the rhizobium of W20 strain inoculants at 200μmol · L-1 Al3+, respectively.Meanwhile NH4-N content of shoot and root was stimulated by 25.7%and 9.4%respectively .%【目的】对我国南方地区的野生大豆根瘤菌进行耐铝的筛选，以期建立一套耐铝根瘤菌筛选和鉴定体系，为南方大豆区接种高效耐铝菌株奠定基础．【方法】利用菌株活化培养法分离来自湖南各县和广州地区酸性土壤中的野生大豆根瘤菌株，通过分光光度计进行耐铝检测，研究耐性菌株的生长特性以及接种后对栽培大豆的生长和结瘤的影响．【结果和结论】菌株W20能在铝浓度为200μmol· L-1的培养基上正常生长，而其他菌株的生长则受到较大抑制．菌株W20的最适生长酸度为pH 6.0，致死酸度为pH 4.0．通过质子通量试验发现，W20的细胞膜能阻止过量的H＋进入细胞．在Al3＋浓度为200μmol· L-1时，华夏3号接种W20菌株后地上和地下部分生物量分别比对照增加了60.9％和14.8％；瘤数和瘤质量分别提高了66％和209％；地上和地下部分铵态氮含量分别比对照高25.7％和9.4％．
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