Isolation and Characterization of Nitrogen Fixing Endophytic Bacteria Associated with Sweet Sorghum (Sorghum bicolor)

Sweet sorghum ( Sorghum bicolor ) has high adaptability to the dryland and resistant to drought. Many endophytic bacteria live in association with their host and play crucial role in health and development of plant. The aims of this work were to isolate and characterize nitrogen-fixing endophytic bacteria associated with sorghum. Sorghum samples were collected from Cibinong Science Center, Cibinong, Bogor, Indonesia. Sorghum werecultivated in four different treatment (compost and inoculants (CI), inoculants (TI), compost without addition inoculants (CN), without compost and inoculants (TN). The samples were sterilized by surface sterilization method and isolation of endophytic bacteria was carried out using spread plate method on TSA medium 1/10. Characterization of endophytic bacteria to fix nitrogen were done using Jensen’s media and tested by specific primers to amplify nif H gene. A total of 89 isolates were successfully isolated from root and stem. Sixteen isolates were able to grow on Jensen’s media. Based on PCR amplification of nif H gene was observed the expected size of the nif H region.