GENERAL MICROBIOLOGY - T.P. Pyrog - 2004

17. MOLECULAR NITROGEN FIXATION

Only prokaryotes are capable of fixing molecular nitrogen. Nitrogen Fixation can be carried out both by free-living Bacteria and by bacteria living in Symbiosis with higher plants (rhizobia). Free-living nitrogen fixers contribute 1–3 kg of nitrogen per hectare of soil annually. As a result of Nitrogen fixation by ROOT-nodule bacteria, 1 hectare of soil is enriched with 100–300 kg of nitrogen per year.



Last update: 12/08/2026

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