Fruit body formation and intra-species DNA polymorphism in Japanese Wolfiporia cocos strains

Poria, the dried sclerotium of Wolfiporia cocos, is a medicinal mushroom that is widely used in traditional Japanese medicine. The fruit body of W. cocos is rarely found in the natural environment in Japan, therefore an optimized technique for fruit body formation is essential for producing new strains through crossbreeding and for biological research. Here, we developed a cultivation technique for fruit body formation of W. cocos using three strains collected from different areas of Japan. When mycelia were cultured on sawdust-based medium after liquid medium culture, all strains successfully formed fruit bodies as a brown honeycomb-like structure. Furthermore, we analyzed single nucleotide polymorphisms of the three strains using the STE3-like pheromone receptor protein gene, STE3.2, and found a genetic marker for discriminating one strain from the others. The results are expected to promote extensive studies on crossbreeding and domestic production of W. cocos.