A micrograph of a Frankia alni culture at a magnification of 100x with hyphae and a nitrogen-fixing vesicle in the center using a 3D filter taken by a post-doctoral fellow, Ms. Lorena Carro, in Dr. Philippe Normand's laboratory.
Whitney Cranshaw, Colorado State University, Bugwood.org
Wikimedia Commons
Description: English: Frankia alni at Alnus sp. Nodule of the nitrogen-fixing bacterium Frankia alni attached to the roots of alder. Source: https://www.forestryimages.org/browse/detail.cfm?imgnum=5574645. Author: Whitney Cranshaw, Colorado State University, Bugwood.org.