【摘要】 为调研甘肃中药材种植区的固氮微生物资源,从党参、黄芪和当归3种药材种植地的根际土壤中分离具有固氮酶活性的微生物,单菌株纯化并进行分子生物学鉴定,最后通过乙炔还原法检测各菌株的固氮酶活性。结果表明:这3种作物的根际土壤中固氮微生物资源丰富,共分离得到28株具有固氮酶活性的菌株,经鉴定主要为根瘤菌属、芽孢菌属、单孢菌属、无色杆菌属和粘着箭菌属等,固氮酶活性为53.5 C₂H₂nmol·（h·ml）-1²95.3 C₂H₂nmol·（h·ml）^-1,无色杆菌属的固氮酶活性较高。此研究为下一步筛选适合中药材生长的微生物固氮菌肥的菌种提供一定的理论依据。更多还原

【Abstract】 In order to study the resources of nitrogen-fixating organism from soils of Chinese herbal medicine in Gansu province,we isolated the microorganisms with nitrogenase activity from herbal rhizosphere soils of Codonopsis,Astragalus and Angelica,respectively; then purified and identified each isolated single strain by molecular biology; finally detected nitrogenase activity of each strain using acetylene reduction. The results showed that the three kinds of rhizosphere soils were with rich nitrogen-fixing organism resources,and 28 isolated strains were mostly identified as Rhizobium sp.,Brevibacillus sp.,Pseudomonas sp.,Achromobacter sp. and Ensifer sp.,with 53. 5 C₂H₂nmol·（ h·ml）^-1 295. 3 C₂H₂nmol·（ h·ml）^-1 of nitrogenase activity; and the nitrogenase activity of Achromobacter sp. was higher than the others. This study provides a theoretical basis for selecting bacteria to produce a highly effective nitrogen-fixing fertilizer using in herbal soils.更多还原