Researching the far-reaching travels of fungi

Nancy Johnson

An NAU professor is joining international researchers to discover how fungi are traveling around the world, a mystery uncovered in a new study released this week in Science.

Nancy Johnson, an NAU ecology professor, contributed field samples to a global-scale study of the biogeography of Arbuscular mycorrhizal fungi, also known as AM fungi. Johnson is listed as an international co-author on the paper.

These fungi support 80 percent of plant species, including crops, by capturing nutrients from soil. Johnson said understanding how different species of AM fungi are distributed around the globe is important because of the vital roles they play in the ecosystem.

Researchers gathered 1,014 fungi samples from six continents, and what they discovered was surprising.

“Our study suggests that most species of arbuscular mycorrhizal fungi are found all over the world, which is rather unusual among organisms,” Johnson said. “The question is, how do they get everywhere?”

While the disbursement of AM fungi was surprising to many researchers, Johnson said she discovered indicators of this back in 1988 as a graduate student. She said she was shocked to see the strong similarities between the communities of fungi in Costa Rica compared to Minnesota. “Back then we used microscopy to identify the fungi from their spores and now, newer molecular methods are showing the same patterns.”

Arbuscular mycorrhizal root tuber.
Arbuscular mycorrhizal root tuber.

For the recently published paper, Johnson, who teaches in the School of Earth Sciences and Environmental Sustainability, provided samples from the Serengeti in Africa. These samples contained the most diverse fungal communities in the entire study.

Northern Arizona University has a strong international reputation for mycorrhizal research. In August, Johnson and biology professor Catherine Gehring, hosted the eighth International Conference on Mycorrhizas, which brought 500 scientists from 52 countries to Flagstaff. Johnson is working with conference presenters on a book detailing some of the latest international research on AM fungi.