Rhizobium is a

Rhizobium is a genus of Gram-negative soil bacteria that plays a crucial role in nitrogen fixation. It is classified as a biofertilizer because it lives symbiotically in the root nodules of leguminous plants (such as peas, beans, and clover), where it converts atmospheric nitrogen (N₂) into ammonia (NH₃), a form that plants can readily use for growth.

• Biofertilizers are preparations containing living cells of microorganisms that help enhance the nutrient status of the soil naturally.
• Biopesticides are biological agents used to control agricultural pests.
• Bioherbicides and mycoherbicides (fungal-based) are used specifically to manage or eliminate weeds.

By naturally enriching the soil with nitrogen, Rhizobium reduces the dependency on chemical fertilizers, making it a key component of sustainable agriculture.