Identification and determination of biological functions of endophytic bacteria 265ZY4 from Stipa capillata

Abstract:

[Objective] The result of this study will provide evidences for the exploration and utilization of plant endophyte from Stipa capillata on alpine meadow, and provide a valuable resource for the study of biological fertilizer. [Methods] This test exploited the conventional methods of separation of endophytic bacteria 265ZY4 from Stipa capillata, and the strain was studied by 16S rRNA sequence analysis and biological characteristics including antibacterial activities, IAA secretion, phosphate solubilization and nitrogen fixation by using in vitro antagonistic tests, Salkowski colorimetry and Mo-Sb colorimetry. [Results] Strain 265ZY4 demonstrated inhibitory activities to three fungal pathogens of potato, the best inhibitory rate of the strain were 83.03% against Colletotrichum coccodes. IAA was secreted by 265ZY4 as high as 9.30 mg/L in the King medium without addition of tryptophan, The strain also possessed the capacity of phosphate solubilization and without the capacity of nitrogen fixation. With the cultural and morphological characteristics, combined with 16S rRNA sequence analysis, the strain 265ZY4 was identified as Bacillus subtilis. [Conclusion] Strain 265ZY4 was preliminarily identified as B. subtilis, and has the good biological function. It should be an interesting isolate for developing agriculture.

Key words:Stipa, Endophytic bacteria, Biological functions, Identification