Rhizobium

Rhizobium is a useful bacterium that lives in the roots of legume plants and helps them get nitrogen for making proteins.

• It lives inside small, swollen bumps on roots called root nodules, found in plants like peas, beans, gram, and lentils.
• Rhizobium can do something most plants cannot: it fixes nitrogen—it changes nitrogen gas from the air (which plants cannot use directly) into nitrogen compounds that plants can use to grow.
• This is a mutual partnership: the plant gives Rhizobium food and a safe place to live, and Rhizobium supplies usable nitrogen to the plant.
• Because legumes get extra nitrogen this way, growing them can improve soil fertility and reduce the need for chemical nitrogen fertilisers.
• A simple real-life link is crop rotation: farmers often grow a legume crop in between other crops so the soil becomes richer in nitrogen for the next crop.

So, Rhizobium acts like a natural “nitrogen helper” for legumes and a natural “soil improver” for farms.