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root nodule

root nodule A swelling on the roots of certain plants, especially those of the family Fabaceae (Leguminosae), that contains bacteria (notably Rhizobium) capable of fixing atmospheric nitrogen into ammonia, which is subsequently converted to nitrates and amino acids (see bacteroid; nitrogen fixation). Plants that possess root nodules increase soil fertility by increasing the nitrate content of the soil. The practice of crop rotation will normally include the cultivation of a leguminous species. Certain nonleguminous plants, such as alder (Alnus) and bayberry (Myrica), also form root nodules, although the bacteria are filamentous actinomycetes (Frankia), not rhizobia.

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"root nodule." A Dictionary of Biology. . Encyclopedia.com. 18 Aug. 2017 <http://www.encyclopedia.com>.

"root nodule." A Dictionary of Biology. . Encyclopedia.com. (August 18, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/root-nodule-1

"root nodule." A Dictionary of Biology. . Retrieved August 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/root-nodule-1

root nodule

root nodule (actinorrhiza) A small, gall-like growth on the roots of certain types of plant, especially leguminous plants. The nodules develop as a result of infection of the roots by bacteria (Rhizobium or Bradyrhizobium species in the case of legumes); the bacteria then inhabit the root nodules and benefit the plant by fixing atmospheric nitrogen, much of which becomes available to the plant.

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"root nodule." A Dictionary of Plant Sciences. . Encyclopedia.com. 18 Aug. 2017 <http://www.encyclopedia.com>.

"root nodule." A Dictionary of Plant Sciences. . Encyclopedia.com. (August 18, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/root-nodule-0

"root nodule." A Dictionary of Plant Sciences. . Retrieved August 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/root-nodule-0

root nodule

root nodule(actinorrhiza) A small, gall-like growth on the roots of certain types of plant, especially leguminous plants. The nodules develop as a result of infection of the roots by bacteria (Rhizobium or Bradyrhizobium species in the case of legumes); the bacteria then inhabit the root nodules and benefit the plant by fixing atmospheric nitrogen, much of which becomes available to the plant.

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"root nodule." A Dictionary of Ecology. . Encyclopedia.com. 18 Aug. 2017 <http://www.encyclopedia.com>.

"root nodule." A Dictionary of Ecology. . Encyclopedia.com. (August 18, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/root-nodule

"root nodule." A Dictionary of Ecology. . Retrieved August 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/root-nodule

root nodule

root nodule Small swelling in the roots of various plants, such as legumes, that contain nitrogen-fixing bacteria. See also nitrogen cycle; nitrogen fixation

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"root nodule." World Encyclopedia. . Encyclopedia.com. 18 Aug. 2017 <http://www.encyclopedia.com>.

"root nodule." World Encyclopedia. . Encyclopedia.com. (August 18, 2017). http://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/root-nodule

"root nodule." World Encyclopedia. . Retrieved August 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/root-nodule