Discovery and Application of the Companion Fungus Related to Sclerotial Formation from Hyphae of Grifola umbellata

The companion fungus (Grifola sp.) related to sclerotial formation from hyphae of Grifola umbellata (Pers.) Pilat was isolated from the cavity associated with sclerotia of G. umbellata in natural condition. Experimental results showed that the pure culture of G. umbellata was unable to form sclerotia, whereas sclerotia produced easily in flasks or on trunks when the companion fungus was inoculated together with strain of G. umbellata. The companion fungus is critical for sclerotium formation from hyphae of G. umbellata. Morphological differences were found in cultures of the two fungi. The companion fungus possesses thin_walled narrow hyphae, while G. umbellata is of wider hyphae which are either thick_ or thin_walled.