Study on Isolating and Selecting Nitrogen Fixation Bacteria in Rhizosphere of Lycium barbarum L.in Ningxia

[Objective] The study aimed to select the best beneficial bacteria from the Ningxia Lycium barbarum L.,which has local climate characteristics and nitrogen fixation characteristic performance.[Method] Nitrogen fixation bacteria of root surface,root surface soil and rhizosphere soil were determined by using NFM(non-nitrogen culture medium).[Result] Quantities,growth speed of strainsand multiplied quantity of single strain separated form root surface were more than that of form rhizosphere soil and root surface;experimente divided 47 nitrogen fixation bacteria from 3 parts.[Conclusion] Root soil had the most strains,secondly for rhizosphere soil,root soil had the least strains.