Organism or group
Bacteria
Small single-celled organisms without a nucleus, found almost everywhere on Earth. Most bacteria in the human body are harmless, and some are helpful.
Nitrogen fixation
Some bacteria turn nitrogen gas into forms plants can use. Legumes house them in root nodules.Source: Oldroyd et al., 2011
Also called rhizobia.
Process
How Nitrogen fixation connects
Nitrogen fixation uses
Nitrogen fixation is related to
Process
Mycorrhizae
Partnerships between plant roots and fungi. A 2018 review estimated that only about 8 percent of vascular plant species have none.
Studied in
Your progress
Sources & further reading
The explanations on this page are our own summaries of these sources. Follow a link to read the original; if anything here disagrees with it, the original wins. How we choose and check sources.
The rules of engagement in the legume-rhizobial symbiosis (opens the original in a new tab)
Oldroyd GE, Murray JD, Poole PS, et al. (2011). Annual Review of Genetics 45:119-144.
Editorially reviewedReview