MEET THE FIRE LOVING FUNGI
–Meliodas012201
When a wildfire obliterates a forest, the first life to rise from the ashes is usually a fungus—one of several species that cannot complete its life cycle without fire. How do pyrophilous (fire-loving) fungi survive, sometimes for decades, between fires?
A study published in Fungal Ecology by UT and the University of Illinois researchers found out that some of these fungi hide out in the tissues of mosses and lichens. There are some study conducted in the Great Smoky Mountains National Park on fungus population since the 2016 wildfire.
The researchers found pyrophilous fungal DNA inside the lichen of the genus Usnea. Several hypotheses are said to explain where pyrophilous fungi live when they’re not reproductively active. Some think spores drifted into a newly burned zone from elsewhere, but how those spores could develop in the absence of fire isn’t clear. Others suggest that fungus is present in the soil, either as a spore or a storage organ that somehow lasts for decades between fires and isn’t consumed by fire.
The team made an unexpected finding that pyrophilous fungi was found had never been documented for the Smokies before this, in spite of focused collecting by three generations of University of Tennessee mycologists. According to Hughes, “Fire has been repressed in the Smokies for 100 years, so where were these fungi hiding, for one pyrophilous species, it seems to exist inside mosses and lichens.”
To determine if the fungi is inside the mosses and lichens rather than present along on their surfaces, researchers disinfected the moss and lichen samples before testing to see if any fungi were inside.
The team found DNA from pyrophilous fungi inside the surface-sterilized mosses and lichens from burned and unburned areas. They also found DNA from pyrophilous fungi in the soils inside and outside the burn area. In addition, the discovery is interesting, since pyrophilous fungi do not fruit outside a burn zone. The presence of their DNA there might suggest they’re persisting in the soil as fire-resistant spores.
However, evidence suggests that these fungi have taken up residence inside these other organisms on the forest floor, tree trunks, or the tree canopy, which has contributed to their lack of detection by traditional means.