酶联免疫吸附技术(ELISA)对大豆根瘤菌的鉴定  

ENZYME-LINKED LMMUNOSORBENT ASSAY (ELISA) FOR SOYBEAN RHIZOBIA STRAIN IDENTIFICATION

作　　者：杨苏声[1] 谢小保[1] 李季伦[1] 

机构地区：[1]北京农业大学微生物专业,北京100094

出　　处：《微生物学通报》1993年第3期129-133,共5页Microbiology China

摘　　要：本文用直接ELISA法检测大豆根瘤菌USDA 110和RTt 50的纯培养菌体和根瘤。确定了该试验的最佳工作条件:酶标结合物HRP—Ab 110和HRP—Ab50的工作稀释度分别为1:3200和1:800,抗体Ab 110和Ab 50的工作稀释度分别为1:3200和1:800,抗原USDA 110和RTt 50的最适工作浓度均为6×10~7细胞/ml。该法能够特异地检测和区别慢生型和快生型大豆根瘤菌。在这两种类型的大豆根瘤菌中,同种内的少数菌株存在交叉反应,通过吸收可以消除,从而使ELISA的检测达到菌株水平。ELISA的最低检测浓度为2×10~5细胞/ml。在冰箱低温(-20℃)和硅胶干燥常温条件下保存根瘤,均不影响ELISA的检测效果,灵敏度不降低。用ELISA研究USDA 110和RTt 50在不灭菌的盆栽土壤中的竞争结瘤能力,发现USDA 110在大豆的不同生育期的占瘤率在75—87.5%,RTt 50则为25-45%,并证实ELISA比凝集法敏感。The direct ELISA was used to detect cells from pure cultures and nodules of Bradyrhizobium japonicum USDA110 and Rhizobium fredii RTt50. The optimum dilution of enzyme-linked conjugates, HRP-Ab110 and HRP-Ab50, was 1:3200 and 1:800 respectively. The optimum dilution of antibodies, Ab110 and Ab50, was 1:3200 and 1:800 separately. The optimum concentrations of antigens, USDA110 and RTt50, were both 6×10~7 cells/ml. Slow and fast-growing soybean rhizobiz can be detected and differentiated specifically by direct ELISA. Among a few strains of these two groups of soybean rhizobia, cross-reaction occurred. This was eliminated by absorption, so that specific strain could be identified by ELISA. The minimal concentration of antigen for detected was 2×10~5 cells/ml. It was found that nodules preserved by drying over silica gel or freezing were equally good, without loss in sensitivity of ELISA. ELISA was used to study the competition of USDA110 and RTt50 with indigenous rhizobia in soil pot experiment. Nodule occupacy of USDA110 ranged from 75-87.5% in different growing season of soybean and RTt50 ranged from 25-45%. The result showed that ELISA was more sensitive than agglutination.

关 键 词：大豆根瘤菌 ELISA 鉴定 

分 类 号：Q939.114[生物学—微生物学]