| Wheat is one of economic mainstays in China. Research on biological nitrogen fixationin wheat is very import to save nitrogenous fertilizer and reduce the environmental pollution.128endogphytic bacterias were isolated from the roots, stems and leaves of wheat. There were most inthe roots, next is stems,leaves at least. After cultivating several generation, we got31strains whichcould grow well on the Ashby plate. Using OD600to evaluate the mass growth of these strains,Kjeldah to evaluate nitrogen fixation activity of the strains. The result is nitrogen fixation activity ofA4，H17，C1，D7were higher than others, the activity can reach to3.6mg/L，3.0mg/L，2.8mg/L，2.7mg/L. Measuring the nitrogen-fixing quantity of strains which are combined each showedthat the nitrogen-fixing quantity of A4+H17is higher than each single. But other combinations areunconspicuous. Evaluation the high efficient strains were A4, H17.Morphological and physiological characters, parts of the16sRNA gene sequence, growth factorswere studied,The results showed as follow: Gram-positive, aerobic, starch hydrolysis, gelatinhydrolysis, Methyl red experiment, VP, peroxidase,urease,using citrate are positive.use glucose andlactose,no bubbles. Identified by16S rDNA, A4and H17are Bacillus aryabhattai strain.Conducted the culture of A4，H17were showed that they could be cultured over a wide rangeof temperature, pH, salt concentrations.The optimum temperature is30℃, initial pH is7. Thebeneficial growth of strain in the10%-15%glucose concentration,4g/L-6g/L NH4Cl and KNO3.Bymeasuring the vaccination A4, H17, A4+H17on Wheat Seed germination, seedling height and rootlength, and showed that the germination of wheat after inoculation higher than non-vaccinated high,but has little effect on seedling height and root length. Combination strains were performanced andpromoted better effective response than single. To sum up, A4, H17has certain promoting effect toplant growth, with potential applications in crop production. |
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