Inocybe is a large genus of fungus with more than 150 described in Sweden and over 500 species described worldwide. The species have traditionally been grouped in a hierarchical system, where kinship is derived from the form, structure and tissue type of the fungus species.
However, these taxonomies have major shortcomings and as a consequence many species have been placed in the wrong kinship group. This has been revealed by researchers in the Department of Plant and Environmental Sciences at the University of Gothenburg.
DNA sequences are often used in research today to investigate kinship. DNA analyses have the advantage that they relatively simply provide large quantities of data. However, at the same time they are expensive and technically complicated, which means that the everyday work of systematising individual fungi is to a large degree still done by hand on the basis of appearance.
Researchers frequently fail to identify the species. Many species have not been scientifically described and an even smaller number have had their DNA sequences documented. The point is that even these “unidentified” DNA sequences are stored in public databases.
This has been the point of departure for the researcher Martin Ryberg at the Department of Plant and Environmental Sciences. By utilizing an entirely new web service Martin Ryberg has searched through and compared all DNA sequences that have been collated from Inocybe throughout the world.
The project, which is presented in a thesis, offers completely new insights into the ecology and distribution of the fungus genus. For example, Martin Ryberg’s data-based DNA studies show that Inocybe occurs in far more environments than was previously thought – from warm tropical to cool alpine.
The thesis also reveals a previously unknown kinship between fungus species that grow in such widely divergent hosts as the Australian eucalyptus and European orchids. Furthermore, the research can demonstrate that many groups within the genus are not related at all as previously believed.
One such example is the Inocybe’s subgenus Inosperma, which after being examined by Martin Ryberg turned out to contain species from two evolutionarily separate lines.
-What we see of fungi when we are in the countryside, the fruiting bodies, comprise only a small part of the actual fungus. Studying fruiting bodies consequently only provides a limited picture of the life of a fungus and of which fungi are present in one place on a given occasion, says Martin Ryberg.
Martin Ryberg’s research is providing increased knowledge of the environments in which fungi prefer to grow, which in its turn is producing new knowledge about ecological evolution.
-The species in Inocybe live in symbiosis primarily with woody plants such as spruce, pine, birch, oak and beech. But through the emerencia web service I have also found DNA sequences that derive from plants such as pyrola and various orchids, as well as from such widely differing hosts and locations as spruces in Sweden, oaks in California, eucalyptus trees in Australia, willows in Japan and tropical trees in Thailand.