Nodules on the root of an alder tree.

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Close-up of nodules on the root of an alder tree, Alnus sp. The nodules are caused by an association with a filamentous nitrogen-fixing bacterium, Frankia sp.

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Size: 3334px × 5050px
Location: Massachusetts, United States
Photo credit: © Custom Life Science Images / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: actinomycete, actinomycetes, alder, alders, alnus, background, bacteria, bacterium, black, close, close-, closeup, filamentous, frankia, islc, macro, mutualism, nitrogen, nitrogen-fixing, nodule, nodules, plain, plantbetulaceae, plants, symbiosis