NITROGEN FIXING BACTERIA (Syllabus: GS Paper 3 – Envi. & Eco)

Context: Recently, researchers found nitrogen-fixing symbiotic organisms displaying organelle-like behaviors.

Nitrogen Fixing Bacteria

• About: These are microorganisms that convert atmospheric nitrogen into fixed nitrogen, essential for plant growth.
• Importance in the Nitrogen Cycle: These bacteria are responsible for over 90% of nitrogen fixation, playing a crucial role in maintaining the nitrogen cycle.
• Types of Nitrogen-Fixing Bacteria: There are two main types: free-living bacteria like Anabaena and Azotobacter, and mutualistic bacteria such as Rhizobium associated with leguminous plants.

Nitrogen Fixation

• About: Nitrogen fixation refers to the conversion of atmospheric N2 into reactive compounds like nitrates, nitrites, or ammonia.
• Importance:  Reactive nitrogen forms produced through fixation are vital for crop growth and development.
• Consequences of Nitrogen Deficiency: Nitrogen deficiency impedes crop growth and compromises their health.
• Biotic Sources: Around 90% of natural nitrogen fixation is carried out by soil microorganisms.
• Abiotic Sources: Natural inducers like lightning and UV rays can trigger abiotic nitrogen fixation.
• Industrial and Technological Nitrogen Fixation: Nitrogen can also be fixed using electrical equipment or through industrial processes.