西藏雪灵芝根际固氮菌的分离与鉴定  

Isolation and Identification of Azotobacter in the Rhizosphere of Arenaria brevipetala

作　　者：崔月 张新军[1] 王瑞红[1] 廖会君 贾锦鹏 CUI Yue;ZHANG Xinjun;WANG Ruihong;LIAO Huijun;JIA Jinpeng(Research Institute of Tibet Plateau Ecology,Tibet Agriculture&Animal Husbandry University,Nyingchi Tibet,860000,China)

机构地区：[1]西藏农牧学院高原生态研究所,西藏林芝860000

出　　处：《高原农业》2023年第6期638-643,共6页Journal of Plateau Agriculture

基　　金：国家自然科学基金(31960013);西藏自治区科技计划项目(XZ202101YD0013C,XZ202301YD0028C);西藏农牧学院研究生教育创新计划项目(YJS2021-22)。

摘　　要：雪灵芝是藏东南色季拉山珍稀药用植物,其根际固氮菌对于雪灵芝适应高寒环境具有重要意义。本文利用Ashby无氮液体培养基对采自色季拉山的雪灵芝根际土样进行固氮菌的富集培养,把富集培养液涂布于Ashby固体培养基来分离固氮菌,并依据形态学指标和生理生化指标对所分离到的固氮菌初步鉴定。从西藏雪灵芝根际土壤样品中分离到2株固氮菌,分别编号为LZ-Azo1和LZ-Azo2,并保存菌种。根据菌落特征、菌体形态及生理生化指标,对这2株固氮菌进行了鉴定,LZ-Azo1为圆褐球固氮菌(Azotobacter chroococcum),而LZ-azo2为链霉菌属(Streptomyces sp.)。分离到的2株固氮菌皆属于自生固氮菌,有助于西藏雪灵芝在高寒环境中获取氮源,对其适应高寒环境至关重要。Arenaria brevipetala is a rare medicinal plant in Sejila Mountain of southeast Tibet,and its rhizosphere azotobacter is of great significance for Arenaria brevipetala to adapt to alpine environment.In this paper,nitrogen free liquid medium of Ashby was used to enrich and culture azotobacter in rhizosphere soil samples of Arenaria brevipetala mat collected from Sejila Mountain,and the enriched medium was coated in Ashby solid medium to isolate azotobacter.The isolated azotobacter was preliminarily identified according to morphological and physiological and biochemical indexes.Two strains of azofixing bacteria,numbered LZ-Azo1and LZ-Azo2,were isolated from rhizosphere soil samples of Arenaria brevipetala in Tibet and were preserved.The two strains of azofixing bacteria were identified according to colony characteristics,cell morphology,physiological and biochemical indexes,and LZ-Azo1 was a round brown ball azofixing bacterium,LZ-azo2 belonged to Streptomyces.The two strains of azotobacter isolates were all autogenous azotobacter,which was helpful for Arenaria brevipetala of Tibet to obtain nitrogen sources in the alpine environment and was crucial for its adaptation to the alpine environment.

关 键 词：雪灵芝 固氮菌 根际微生物 菌种鉴定 

分 类 号：S718.8[农业科学—林学]