兰州唐古特白刺根际微生物分离鉴定

Isolation and identification of microorganisms in Nitraria tangutorum Bobr. rhizosphere in Lanzhou

摘要:

【目的】从兰州唐古特白刺根际分离得到对植物有潜在促生效果的功能微生物，为研发相关菌种制剂的研究奠定基础。【方法】通过平板划线法从其根际分离纯化出6株细菌，并对菌株进行形态特征观察、革兰氏染色等一系列生理生化试验。用藜麦检测各菌株的促生功能，并对具有优良促生作用的1个菌株16S rRNA基因进行分子鉴定及基因草图绘制。【结果】根据生化鉴定结果，6株细菌分别属于不动杆菌属(Acinetobacter)、土壤杆菌属(Agrobacterium)、类芽孢杆菌属(Paenibacillus)、芽孢杆菌属(Bacillus)、鞘氨醇单胞菌属(Sphingomonas)和假单胞菌属(Pseudomonas)。其中，16S rRNA基因鉴定BC4属于肠杆菌属(Enterobacter)，具有较好的促生效果。【结论】BC4具有较好的促生效果，为兰州唐古特白刺菌种资源的开发和利用提供了一定的理论依据。

关键词:唐古特白刺;根际微生物;菌种鉴定;促生菌筛选

Abstract:

[Objective] Microorganisms with potential growth-promoting effects on plants were isolated from the rhizosphere of Nitraria tangutorum Bobr. in Lanzhou City, which laid a foundation for research and development of related preparations.[Methods] With the plate streak method, 6 bacterial strains were isolated and purified from the rhizosphere of N.tangutorum, and the morphological characteristics of the strains were observed. The physiological and biochemical properties were examined based on Gram staining and other tests. The effect of each strain on quinoa growth was determined. The 16S rRNA gene of a strain with excellent growth-promoting effect was sequenced and the circular genome map for the strain was plotted.[Results] According to the biochemical identification results, the 6 strains belonged to Acinetobacter, Agrobacterium, Paenibacillus, Bacillus, Sphingomonas, and Pseudomonas, respectively. Further identification by 16S rRNA gene sequencing suggested that BC4, with strong growth-promoting activity, belonged to Enterobacter.[Conclusion] BC4 shows strong growth-promoting activity, which lays a theoretical basis for development and utilization of bacterial resources of N.tangutorum in Lanzhou.

Key words:Nitraria tangutorum Bobr.;rhizosphere microorganisms;species identification;screening of growth-promoting bacteria