Diazotrophs Rhizobium

In terrestrial ecosystems the symbiotic bacteria, particularly strains from the genus Rhizobium, play the most important role in N fixation. These bacteria are found on the roots of many leguminous plants (soybeans, clever, chickpeas, etc.). There are other symbiotic diazotrophs (nitrogen-fixing microbes), but till now the Rhizobium has been the most extensively studied. 

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