Aspergillus

Aspergillus spp.
By Cliff Bueno de Mesquita

September’s microbe of the month is the genus of fungi Aspergillus. Aspergillus is a mold type of fungus and is another fungus that we’ve found in the roots of alpine plants on Niwot Ridge, Colorado. However, the genus is very widespread, and can be found indoors as well. 

Interestingly, it was also one of the few fungal taxa that we found in air samples that we collected at Niwot Ridge last summer. We put up air filters (Figure 1) that trap fungal spores and other microbes to examine potential dispersal limitation of microbes. In other words, are microbes able to be blown all over the landscape, or are they only able to reach some random locations?

Figure 1. Passive air filter for sampling airborne microbes.

​Unlike some of the other fungi I have written about, Aspergillus is typically pathogenic to plants and can even cause disease in humans and other animals too. While mycorrhizae take carbon from plants, they give the plants nutrients in return and have a beneficial effect. Pathogens like Aspergillus take resources from plants without giving them anything in return. One of the most abundant species in the genus, Aspergillus fumigatus, can cause pulmonary infections in humans. There has been a lot of work on Aspergillus in the agricultural field, as some species have been known to cause disease on important crops such as corn. 

References:

CDC. 2015. Sources of Aspergillosis. https://www.cdc.gov/fungal/diseases/aspergillosis/causes.html

Pioneer. 2017. Aspergillus ear rot. https://www.pioneer.com/home/site/us/agronomy/crop-management/corn-insect-disease/aspergillus-ear-rot/

The Aspergillus website. http://www.aspergillus.org.uk/