Abstract | Plant growth promoting bacteria (PGPB) is the bacteria that inhabit the plant rhizosphere and have an ability to promote the growth of plant and could increase crop yield by fixing atmospheric nitrogen, and solubilizing insoluble phosphate into the form that available to be uptake by plants. This project aimed to isolate two types of PGPB including nitrogen fixing bacteria (NFB), and phosphate solubilizing bacteria (PSB) on selective media namely Burk’s medium, and Pikovskaya medium respectively. NFB could grow well on Burk’s medium which is nitrogen free medium as NFB have an ability to fix atmospheric nitrogen. Besides, PSB able to grow on Pikovskaya medium that contain insoluble phosphate due to its ability to solubilize phosphate into soluble form which cause the formation of halo zone around the colonies. Total of 391, and 59 colonies of NFB, and PSB respectively were successfully isolated. Ten colonies of NFB were selected due to its ability to grow relatively faster than other colonies, while nine colonies of PSB were selected based on the diameter of halo zone formed on Pikovskaya agar. All of the isolates were then characterized its cellular morphology by performing gram staining. Seven of the NFB isolates are gram-negative rod, while other three are gram-negative cocci, gram-positive rod, and gram-positive. Moreover, three of PSB isolates are gram-negative rod, and six of the PSB isolates are gram-positive rod. The ability of the isolates in fixing nitrogen and solubilizing phosphate were evaluated by determination of nitrogen fixing ability on Burk’s medium, and by measuring the phosphate solubilizing activity using phosphate solubilization index (PSI) test
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