The Rhizobium is a type a type of bacterium which is present in the roots of the leguminious plants like the pea plant, actually after the harvesting of the crops they become defficient in various nutrients and one of the major and important nutrient is Nitrogen. the plant cannot absorb the nitrogen from the atmosphere as they do for the carbon di oxide so these types of plants have the Rhizobium in their roots which convert the atmospheric nitrogen into nitrogeneous compound which can be digested by the plants very easily, but these bacteria cannot make their own food so the roots of the plant where they live provides them with the food and this living together for the development of both the organisms is called as sybiosis, HENCE it is very important for plants and directly/indirectly useful for the HUMANS.
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