Ultra-low freezing to preserve the lingzhi or reishi medicinal mushroom Ganoderma lucidum (Agaricomycetes)

Ganoderma lucidum (Curtis) P. Karst., commonly used in traditional Chinese medicine, is characterized by strong genetic and phenotypic variability that reflects its active components. To preserve such a source of pharmacologically active metabolites, specimens must be collected from different geographic regions and their genetic integrity ensured during storage. To this aim, we tested the effect of ultra-low freezing (ULF) at −120°C on the vitality, mycelial growth rate, and fruiting ability of 3 Italian strains of G. lucidum. Results showed that all strains reacted positively to ULF, demonstrating an ability to recover after 3 months of storage without morphological or physiological changes occurring, regardless of treatment. The successful storage of G. lucidum at −120°C opens up the possibility to create a germplasm bank to collect strains of this medicinal fungus from throughout Europe, thereby contributing to the maintenance of its diversity.