Study on A Nitrogen-Fixing Pantoea Agglomeras Isolated from the Root of Sugar Cane
LI Xinghong, LI Dachei, LI Wei, PENG Lie
(Department of Technical Physics, Peking University, Beijing, 100871)
Abstract:
A strain of nitrogen-fixing bacteria, W11, isolated from the root of sugar cane has been
identificated as Pantoea agglomeras using an auto-identificat ion system for bacterium based
on 96 biochemical test data. W11 has the properties of tolerance to acid(pH3.5) and high
sucrose concentration (30%), A amount of acid was formed and reduced the acidity of
medium to pH of 4.41, the nitrogenase activity was inhibited in presence of 3.1mmol
NH4NO3 or 58.5mmol NaNO3. The optimum growth and maximum nitrogenase activity of
W11 occurs at the medium containing 10% sucrose and 0.25g/L sodium glutamate, pH5.5,
28-30oC. Its behaviours of tolerance to acid and high sucrose concentration,
acid production and the use of carbon substrates is simiiar to that the Acetobacter
diazotrophicus has. The strain W11 was inferred to have a nitrogen-fixing relationship
associated with the root of sugar cane.
Key words:
nitrogen fixation; root of sugar cane; identification of strain; biochemical test; Pantoea
agglomeras