The return of Fomitopsis officinalis to the Italian Alps: preliminary assessment of strategies for conservation and sustainable use

Fomitopsis officinalis (Batsch) Bondartsev & Singer (Fomitopsidaceae, Polyporales) is a holoarctic species developing perennial basidiomata on old conifer stems and, in the Alps, strictly connected with Larix decidua. Since the first century AD it has been known as a natural medicinal product against several ailments, particularly pulmonary diseases. Similar uses have been documented among native peoples of America, the Urals and the Alps, and the fungus is still used in traditional medicine in eastern Asia. This species is now known to contain antibiotic and antiviral molecules (mostly chlorinated coumarines and agaricinic acid) particularly efficient against the Mycobacterium tuberculosis complex, Gram-negative bacteria, Herpes virus, H5N1, H3N2, Poxviridae and Orthopox virus. By the start of the 20th century, F. officinalis had attracted the interest of the pharmaceutical industry in Europe, and this induced unsustainable harvesting which almost led the species to extinction, and which continues today. In addition to restrictions preventing harvesting in natural reserves and parks, F. officinalis has been included in red lists by at least 6 European countries. Based on population decline and habitat loss, it has been proposed for the global red listing with, respectively, endangered or vulnerable status [http://iucn.ekoo.se]. Fomitopsis officinalis and its habitat have been successfully protected 22 * presenting author; [L] lecture; [P] poster in Switzerland [www.wsl.ch/notice_champignons]. Together with small local reservoirs, this is likely to play a major role in restoring populations beyond Swiss borders. Our present work aimed to generate preliminary maps of fruiting individuals, to isolate mycelium into pure culture, and to characterize the species both morphologically and at a molecular level. Basidiomata were sampled from Graian, Pennine, Lepontine and Retic Italian Alps (mostly in protected areas) and identified by morphological characters. Mycelium was characterized morphologically, isolated into pure culture and subsequently processed through molecular analysis to confirm the identification. All 20 isolates were confirmed to be F. officinalis. Almost all analysed cultures had roduced chlamydospores and/or conidia within a few weeks on 2% MEA (Biokar Diagnostic) despite slow growth; brown pigmentation on the reverse was often present. We confirmed that the species is related to old stems of L. decidua, where F. officinalis provokes a very slow brown rot; only living trees were found to host basidiomata. Despite excessive and unregulated harvest, F. officinalis has survived in small reservoirs which are now restoring populations in Alpine valleys, more so close to Swiss borders, probably as a consequence of the protection status there in force. Habitat conservation (old larches) is critically important. This species represents a resource for Alpine areas, but its slow growth and the limited basidiomatal production means harvesting of wild specimens should be abandoned, and cultivation strategies and sustainable use of mycelium should be explored as an alternative to using basidiomata.