论文部分内容阅读
采用无氮培养基,从大豆根际土壤中分离获得4株具有固氮能力的菌株:LS01、LS04、LS05和LS06。根据菌落的形态特征及16S r DNA序列比对分析,结果表明:LS01属于Microbacterium sp.,LS04属于Streptomyces sp.,LS05属于Micromonospora sp.,LS06属于Sarocladium sp.,在无氮液体培养基中培养64 h生物量均达到最大且能够分泌吲哚乙酸(IAA)。利用乙炔还原法对4种菌的固氮酶活性进行测定,固氮酶活测定结果表明4种菌均具有较高的固氮酶活性。因此,Microbacterium sp.LS01,Streptomyces sp.LS04,Micromonospora sp.LS05和Sarocladium sp.LS06具有一定的固氮能力并能分泌IAA,在制备大豆生物菌肥方面具有较好的应用前景。
Four nitrogen-fixing strains, LS01, LS04, LS05 and LS06, were isolated from soybean rhizosphere soil using nitrogen-free medium. According to the morphological characteristics of the colonies and 16S r DNA sequence alignment analysis, the results showed that: LS01 belongs to Microbacterium sp., LS04 belongs to Streptomyces sp., LS05 belongs to Micromonospora sp., LS06 belongs to Sarocladium sp., Cultivated in liquid nitrogen-free medium 64 h biomass was the largest and able to secrete indole acetic acid (IAA). The nitrogenase activity of four kinds of bacteria was measured by acetylene reduction method. The results of nitrogenase activity assay showed that all four kinds of bacteria had high nitrogenase activity. Therefore, Microbacterium sp. LS01, Streptomyces sp. LS04, Micromonospora sp. LS05 and Sarocladium sp. LS06 have certain nitrogen fixation ability and can secrete IAA, which has a good application prospect in the preparation of soybean bio-fertilizer.