Symbiotic Nitrogen Fixation
As part of the nitrogen cycle, the chemical processes by which atmospheric nitrogen is assimilated into organic compounds, particularly by certain microorganisms. The supply of fixed or usable sources of nitrogen restricts crop plant productivity and, as a result, food production. In the developing world, nitrogen fertiliser production is currently a major cost for the efficient growth of various crops. The mechanism is only present in bacteria and archaea, and not in eukaryotes.