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Recovery of 66 fungus stock cultures including Oomycota, Zygomycota, Ascomycota, Basidiomycota, and mitosporic mycetes were examined after cryopreservation. Almost all the stock cultures remained viable when the mycelia that had grown over the sawdust medium containing 10% glycerol as the cryoprotectant (65% moisture content, W/W) were frozen rapidly at Ϫ85°C and then allow to thaw naturally at room temperature. Test stock cultures were preserved for more than 10 years by this preservation method without any programmed precooling and rapid thawing for their cryopreservation. Most of the test fungi could survive for 5 years in medium containing 10% glycerol even after alternate freezing and thawing at intervals of 6 months. When a strain of Flammulina velutipes was tested for mycelial growth rate and productivity of fruit-bodies after cryopreservation for 3 years, the fungus reproduced with its initial capability. These results demonstrate that the sawdust-freezing method using a cryoprotectant is expected to be a reliable and easy preservation method for fungus stock cultures.

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Anatomical changes in traumatic phloem resin canal formation induced in Chamaecyparis obtusa S. ' Z. were examined periodically after mechanical wounding. Five to seven days after wounding, the parenchyma cells close or closest to the cambium at the time of injury expand radially, and then between the seventh to the ninth day, the expanding parenchyma cells developed into tangential rows. Some of the cells simultaneously divided periclinally within nine to fifteen days after being wounded. Moreover, derivatives schizogenously separated from each other and continued to divide. The spaces were enlarged by tangential and radial division of parenchyma cells. The axial and ray parenchyma cells divided mainly periclinally and also anticlinally to form canals, and eventually, circular or elliptic resin canals c. 100 to 200 µm in diameter in regular tangential rows, separated by ray cells. Traumatic phloem resin canals form a tangentially anastomosing network.