, Volume 23, Issue 4, pp 333–340 | Cite as

Microwave-assisted technology for the clearing and staining of arbuscular mycorrhizal fungi in roots

  • Yolande DalpéEmail author
  • Sylvie Marie Séguin
Short Note


The use of microwave irradiation as a source of energy to clear and stain intra-radical arbuscular mycorrhizal fungi propagules has been tested on a variety of indigenous and cultivated herbaceous plants. The aim of the study was to evaluate the efficiency of microwave irradiation on root softening, fungi tissue staining, and preservation of DNA integrity for subsequent molecular analyses. The proposed methodology has been adapted from the standard procedures used to detect and quantify mycorrhizal root colonization levels. Using a domestic microwave oven, tissue clearing and staining required together between 30 s and 1.5 min of microwave treatment to be completed, depending the diameter size of the roots. The well-performing chemical stains tested were acid fuchsin, trypan blue, and aniline blue. The acid fuchsin clearing and staining processes, as performed, were also demonstrated to preserve DNA integrity for further molecular analyses. Irradiation by microwaves has been used with success in our laboratory within the frame of several studies. It offers considerable time saving over traditional method, reducing processing times from several hours to a few minutes while decreasing considerably the amount of chemicals and energy required to perform analyses.


Irradiation Root colonization Root clearing Root staining 



Gratitude is expressed to all collaborators who tested and commented on the methodology described. Special thanks to Dr. S. Redhead from Agriculture and Agri-Food Canada for the revision of the manuscript.


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Copyright information

© Her Majesty the Queen in Right of Canada as represented by: Marc Savard 2013

Authors and Affiliations

  1. 1.Agriculture and Agri-Food CanadaOttawaCanada

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