Nitrogen fixation is essential to life because fixed inorganic nitrogen compounds are required for the biosynthesis of all nitrogen - containing compounds. Therefore, as part of the nitrogen cycle, it is essential for agriculture and the manufacture of fertilizer. It is also, indirectly, relevant to the manufacture of all chemical compounds that contain nitrogen, which includes explosives, most pharmaceuticals, and dyes. Nitrogen fixation is carried out naturally in the soil by a wide range of nitrogen fixing Bacteria and Archaea, including Azotobacter. Some nitrogen - fixing bacteria have symbiotic relationships with some plant groups, especially legumes. Looser relationships between nitrogen - fixing bacteria and plants are often referred to as associative or non-symbiotic, as seen in nitrogen fixation occurring on rice roots. It also occurs naturally in the air by means of NOx production by lightning.
which bacteria helps nitrogen fixation in the soil
Azotobacter