Visualization of Hyphal Sheath in Wood-Decay Hymenomycetes. I. Brown-Rotters

Abstract

Several brown rot fungi were studied with respect to formation of hyphal sheaths in axenic culture. The 12 fungi [Coniophora arida, C. puteana, Gloeophyllum trabeum, Lentinus lepideus, Poria placenta, Serpula incrassata, Fomitopsis meliae, Laetiporus sulphureus, Leucogyrophana arizonica, L. olivascens, Poria carbonica, Serpula himantioides] examined showed hyphal sheaths when grown on each type of solid substrate; in isolates grown in liquid media, sheaths were poorly demonstrated. Sheath structure varied among and within species, but a fine fibrillar texture was common to all. Sheath of P. carbonica might also be granular or composed of electron dense granules and rods. A sheath often contained cellular contents released from hyphae autolyzing within the sheath. Occasionally protoplasm could be seen escaping through openings in cell walls. Necrotic hyphae lacked sheaths.