TAILIEUCHUNG - Characterization and identification of nitrogenfixing bacteria isolated from agricultural soil

To isolate and characterise free nitrogen-fixing bacteria, we collected randomly soil samples from different areas of Ha Noi. Nitrogen-fixing bacteria were isolated using Burk’s medium without nitrogen mineral supplement. The ammonia (NH4 + ) synthesis of these bacterial strains after biomass production was determined by means of Nessler reagent. Based on the results of isolation, we observed and evaluated colony and cellular morphology, pigment production, and metabolic activities of twenty-five isolates. Among the isolated bacteria, two bacterial strains ( and ) with high NH4 + concentration in the cultural medium were selected as the best strains for nitrogenfixing ability. The optimal pH and temperature for their growth and nitrogen fixation are and 30°C, respectively. Growth is best favored in the presence of sucrose. We sequenced the 16S rRNA gene of selected strains and compared the homology of them in GenBank using BLAST search. The result of the comparison shows that the and strains have 99% and 100% 16S rRNA-sequence similarity with Pseudomonas sp. and Bacillus sp., respectively. | Characterization and identification of nitrogenfixing bacteria isolated from agricultural soil

• Sinh học
• Biological nitrogen fixation
• Nitrogen fixing bacteria
• Identification of nitrogenfixing bacteria isolated
• Agricultural soil
• 16S rRNA sequence similarity
• Soil fertility
• Nitrogen economy
• Environmental terms
• Review on the role
• N2 fixation
• Antagonistic effect
• Biological control bacteria pseudomonas
• Inhibits free nitrogen fixing bacteria
• Nitrogen fixing bacteria in the rhizosphere
• BMC Bioinformatics
• Artificial neural networks
• Protein classification
• Azospirillum brasilense
• Operon draTGB
• Tripartite symbiotic
• cowpea genotypes
• poverty alleviation
• BNF applications
• sustainable agriculture
• Bacteria inoculation
• Efficiency parameters
• Organic farming
• Organic wheat farming
• Enhancement of nodulation efficiency
• Nodulation efficiency of mungbean Rhizobia
• Mungbean Rhizobia
• Nodulation efficiency
• Higher biological nitrogen fixation