Nitrogen fixation is the process by which certain microorganisms convert atmospheric nitrogen into a form that plants can use. In soil, nitrogen-fixing bacteria such as Rhizobium and Azotobacter play a crucial role in this process. These bacteria have the enzyme nitrogenase, which enables them to convert atmospheric nitrogen (N2) into ammonia (NH3) or nitrate (NO3-), which can be absorbed by plant roots. This fixed nitrogen is essential for plant growth and is a vital component of proteins, nucleic acids, and other important molecules in plants. Through this symbiotic relationship between nitrogen-fixing bacteria and plants, the nitrogen cycle is completed in soil, ensuring the availability of nitrogen for plant growth and ecosystem functioning.
