What is the role of symbiotic …

A species of bacteria called Rhizobium, help in nitrogen fixation. These bacteria live in the roots of leguminous plants (e.g., pea and beans plants) and using certain types of enzymes, they help in fixing nitrogen in the soil. During this biological process, they convert the non-absorbable nitrogen form into a usable form. This form of the nitrogen gets dissolved in the soil, and plants absorb the modified nitrogen from the soil. This is the reason behind farmers implementing crop rotation, where leguminous plants help to replenish nitrogen content in the soil without the necessity of fertilizers.

Nitrogen fixation by bacteria is an example of the symbiotic relationship between Rhizobium and the leguminous plants. While bacteria fix nitrogen in the soil, plants provide them food.