Question

How do rhizobium bacteria increase the fertility of soil?

Answer 1

Rhizobium bacteria helps in nitrogen fixation. They form symbiotic relationship with leguminous plants.

Rhizobia are found in the soil and after infection, produce nodules in the legume where they fix nitrogen gas (N2) from the atmosphere turning it into a more readily useful form of nitrogen. From here, the nitrogen is exported from the nodules and used for growth in the legume. Once the legume dies, the nodule breaks down and releases the rhizobia back into the soil where they can live individually or reinfect a new legume host.