Study
The role of root exudates in rhizosphere interactions with plants and other organisms
Bais, Harsh P.; Weir, Tiffany L.; Perry, Laura G.; Gilroy, Simon; Vivanco, Jorge M.
Annual Review of Plant Biology, 2006
A review of the compounds plant roots release into surrounding soil and what they do: attracting and selecting microbes, inhibiting competitors, recruiting nitrogen-fixing partners and establishing mycorrhizal associations.
- Studied in
- Plantae, Bacteria, Fungi
- Sample size
- review of root chemistry and rhizosphere interactions
Roots release a substantial fraction of fixed carbon into the soil as a chemically diverse exudate. Specific compounds attract or repel specific microbes, initiate symbiotic relationships, and in some species inhibit the germination or growth of neighbours. The composition changes with the plant's condition and with what is present in the soil.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Root exudates are the principal medium of chemical interaction between plants and the soil community, and are actively regulated rather than passive leakage.
How NatureHQ reads it
This closes the gap NatureHQ had already flagged on its own page: below-ground chemistry was represented only by fungal networks, which is one channel out of several. A plant is spending a serious share of its photosynthetic income on chemicals it pushes into the soil, and the composition changes with circumstances. Some of it recruits partners, some of it suppresses rivals, and the distinction between those matters for the same reason as above — recruiting a partner that benefits from responding looks much more like signalling than poisoning a competitor does.
- A review across a chemically enormous and unevenly studied field.
- Much of the underlying work uses hydroponic or sterile systems that differ greatly from soil.
- Allelopathic claims in particular have often not survived field testing.
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Published by: Annual ReviewsPublished in an Annual Reviews journal.
doi.org/10.1146/annurev.arplant.57.032905.105159
This reference was resolved automatically against Crossref on 2026-08-11.
NatureHQ summarises research in its own words and does not reproduce published text. Reviewed 2026-08-11.