The Medicinal Wood-Decay Species Laricifomes officinalis in the Alpe Veglia–Alpe Devero Natural Park (Italian Alps): Spatial Analysis and Growth Tests of Pure Cultures

Laricifomes officinalis is a wood-decay fungus that is closely associated with old individuals of Larix decidua . In the twentieth century, L. officinalis was over-harvested because of its medicinal properties; consequently, it has become very rare or almost extinct in the Alps. In this study, we investigated the population of L. officinalis in the Alpe Veglia–Alpe Devero Natural Park (Val d’Ossola, Italy) to assess a preliminary conservation strategy. Population consistency was estimated using field mapping, and spatial analysis was performed on host trees based on topographical and environmental variables. Mycelia were isolated from harvested basidiomata, and strain identity confirmed by molecular analysis of the ITS region. All isolated strains were tested for growth in Petri dishes containing different standard media to determine which strains had the highest growth rates; the fastest growing strains may be selected for future studies and applications. Compared to the control strains from Val Malenco and Parco Nazionale del Gran Paradiso, all strains from Alpe Veglia–Alpe Devero Natural Park had lower growth rates. There was no significant difference between the growth rates of strains from Alpe Veglia and those from Alpe Devero. The results suggest that the population consistency of L. officinalis in the Alpe Veglia–Alpe Devero Natural Park is related to two main factors: habitat preservation and harvesting prohibition. These results confirm the need to protect L. officinalis both inside and outside natural reserves, despite the apparent increase in local populations.