ABSTRACT
Salinity is the most important factor for the growth of crops. It is an effective method to alleviate the toxic effect caused by salt stress using saline-alkali-tolerant and growth-promoting bacteria in agriculture. Seven salt-tolerant bacteria were screened from saline-alkali soil, and the abilities of EPS production, alkalinity reduction and IAA production of the selected strains were investigated. A dominant strain DB01 was evaluated. The abilities of EPS production, alkalinity reduction and IAA production of strain DB01 were 0.21 g/g, 8.7% and 8.97 mg/L, respectively. The isolate was identified as Halomonas aquamarina by partial sequencing analysis of its 16S rRNA genes, and had the ability to inhibit the growth of Fusarium oxysporum f. sp., Alternaria solani, Phytophthora sojae and Rhizoctonia cerealis. It also could promote root length and germination rate of wheat seedlings under salt stress. Halomonas aquamarina can provide theoretical basis for the development of soil microbial resources and the application in saline-alkali soil improvement.
Subject(s)
Alkalies , Metabolism , Bacteria , Genetics , Halomonas , Genetics , Plant Roots , Microbiology , RNA, Ribosomal, 16S , Genetics , Salt Tolerance , Genetics , Seedlings , Microbiology , Soil , Chemistry , Soil Microbiology , Triticum , MicrobiologyABSTRACT
Objective:To investigate the growth-promoting properties and applicability of the mycoplasma test culture media pre-scribed in Chinese pharmacopoeia, and provide reference for the standardization of the drug mycoplasma test method. Methods: Re-spectively using four quantitative detection methods including sensitivity, degree of color change, colony counts and colony diameter, and mycoplasma media widely used in the world as the reference media, the growth-promoting properties of 4 batches of mycoplasma broth and 4 batches of arginine mycoplasma broth from four domestic manufacturers were investigated. Results:The results of sensitivity assay and absorbance detection showed that all the media inoculated with below 100 CFU test microorganisms exhibited visible color change. Furthermore, the results of color change degree and colony diameter showed that there were significant differences among the media products from different manufacturers(P<0. 01). Conclusion:Mycoplasma broth and arginine mycoplasma broth both can sup-port the growth of below 100 CFU test microorganisms. Due to the difference in the growth-promoting properties among the media prod-ucts from different manufacturers, the drug mycoplasma test workers should use more sensitive methods to examine the applicability of the media.