SLU news

DNA mapping gives new insight into Swedish fungi

Published: 07 September 2023
Soil sample.

There are far more species of fungi in the ground than previously known. Fungi visible to the naked eye are in the minority according to a 10-year DNA mapping now available on the website Svampar i Sverige.

DNA is famously used to solve cold crime cases. But the technology can also be applied in the forest. Since 2015, researchers have carried out a national mapping of fungi in Swedish forests. Results show there are far more species in the ground – invisible to the naked eye – than previously known. Many common and important mycorrhizal fungi are invisible above ground. Says Anders Dahlberg, professor of mycology and one of the founders of the fungi mapping:

– We’ve learned that there’s much more fungi in the ground than we thought. Many of the species we can see and observe only constitute a small part of what is out there.

According to Anders Dahlberg, the greatest upside of the DNA project is how it provides new knowledge of fungi diversity, on a big scale and in a cost-effective way. This can be used in research and for environmental monitoring purposes.

– Just like we learn more and more about microbes in our bodies and how they affect us, we’re now learning more about fungi and their roles in nature. For example, we now know that in places where certain species of webcap grow, carbon sequestration is around 30 percent lower, says Dahlberg.

A new and improved method

Previously, a lot of what we knew of forest fungi was based on inventories of fruit bodies. But many species don’t form a fruit body, and whereas mycelium grows all year, a fruit body is generally only visible during a short window of time. With a DNA analysis of a soil sample, all fungi can be detected at any time. These DNA hits are then matched against a registry of known species.

Soil samples are gathered on permanent plots used by the Swedish NFI and the Swedish forest soil inventory. This type of coordination means fungi results can be combined and analysed with all data on forest and soil conditions. There is also a logistical upside: it’s very cost-effective using a team that is already on-site, to take an additional, small soil sample.

New website

Data from the fungi mapping project (up until 2019) has been published on the new website svamparisverige.se. Visitors can filter their results in a number of ways, to see where and in what type of forest different fungi species grow. More data will be added in the future, to give even more detailed results regarding the relationship between fungi species and forest environments.

Facts:

The DNA mapping of fungi was financed by Formas, the Swedish Environmental Protection Agency (EPA) and SLU, The Swedish University of Agricultural Sciences. Financing for continued work is secured through the EPA. The website svamparisverige.se was paid for by SLU Environmental monitoring and assessment (EMA), and the Anna and Gunnar Vidfelt foundation.