CALCIUM TRANSLOCATION, CALCIUM-OXALATE ACCUMULATION, AND HYPHAL SHEATH MORPHOLOGY IN THE WHITE-ROT FUNGUS RESINICIUM BICOLOR

The white-rot fungus Resinicium bicolor was cultured on wood blocks in a modified soil block assay and was observed by environmental scanning electron microscopy and scanning electron microscopy. Resinicium bicolor was found to translocate calcium in mycelial cords in quantities greater than that found in the wood blocks and accumulated this calcium in the form of calcium oxalate. Calcium oxalate crystal clusters of mycelial cords were 3 X larger and far more numerous than the crystal clusters produced by the same fungus within the wood. Environmental scanning electron microscopy technology allowed for the examination of the hyphal sheath in a hydrated state. The hydrated hyphal sheath was found to be much thicker than the desiccated sheath observed after standard scanning electron microscope preparations. Calcium oxalate crystals were found to be embedded in the thick hyphal sheath, suggesting that previous observations of within-wall calcium oxalate precipitation may perhaps be better interpreted as artifacts generated during sample preparation.