Fig. 26.28 Root nodules induced by rhizobia on legumes. This image shows the appearance of
nodules which bacteria of the rhizobial group induce on the roots of legumes. The rhizobial nodules
can differ in appearance depending upon the host plant species. The upper image shows roots of
Vigna unguiculata, which commonly is called cowpea. I have grown Vigna unguiculata subsp.
sesquipedalis in my yard. The common names of that subspecies include asparagus bean and
Chinese long bean. The beans of Vigna unguiculata subsp. sesquipedalis taste very good when
cooked Chinese style! The title of this upper image is “Rhizobia nodules on Vigna unguiculata.jpg”
by author Stdout and it is being used under a Creative Commons Attribution-Share Alike 3.0
Unported license. The lower image shows roots of Lotus pedunculatus containing nodules that
similarly were induced by rhizobial bacteria. Members of the genus Lotus are called trefoils. The
common names for Lotus pedunculatus include big trefoil and greater bird's-foot-trefoil. The title of
this lower image is “Lotus pedunculatus11 ies.jpg” by author Frank Vincentz and it is being used
under a Creative Commons Attribution-Share Alike 3.0 Unported license
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C. J. Hurst