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• 1. [Article] Assessing Biocide Effects on Protoplasts of Wood Decay Fungi

  Hyphal fragments and protoplasts of two wood-degrading fungi, Postia placenta and Trametes versicolor, were used to examine the effects of two fungicides, copper sulfate and azaconazole, on fungal health ...

  Citation × Citation Citation Abstract Copy Title: Assessing Biocide Effects on Protoplasts of Wood Decay Fungi Author: Rui, Chen, Morrell, Jeffrey J. Hyphal fragments and protoplasts of two wood-degrading fungi, Postia placenta and Trametes versicolor, were used to examine the effects of two fungicides, copper sulfate and azaconazole, on fungal health (as measured by oxygen consumption, glucose utilization, potassium levels, cell regeneration, and copper uptake). Although both cell systems responded to the presence of fungicide, there were some differences in response. Protoplasts tended to absorb higher levels of copper and were less sensitive to copper sulfate than were mycelial fragments. In general, however, protoplasts provided uniform cells for evaluating the effects of fungicides on cell health. Title: Assessing Biocide Effects on Protoplasts of Wood Decay Fungi Author: Rui, Chen, Morrell, Jeffrey J. Hyphal fragments and protoplasts of two wood-degrading fungi, Postia placenta and Trametes versicolor, were used to examine the effects of two fungicides, copper sulfate and azaconazole, on fungal health (as measured by oxygen consumption, glucose utilization, potassium levels, cell regeneration, and copper uptake). Although both cell systems responded to the presence of fungicide, there were some differences in response. Protoplasts tended to absorb higher levels of copper and were less sensitive to copper sulfate than were mycelial fragments. In general, however, protoplasts provided uniform cells for evaluating the effects of fungicides on cell health. Close

• 2. [Article] Decay resistance and extractive content of second-growth Port Orford cedar (Chamaecyparis lawsoniana) wood

  Port Orford cedar (Chamaecyparis lawsoniana) has a reputation for being resistant to fungal attack, but much of the work to support this premise used older growth material (80-100 yr old). Given the tendency ...

  Citation × Citation Citation Abstract Copy Title: Decay resistance and extractive content of second-growth Port Orford cedar (Chamaecyparis lawsoniana) wood Author: Morrell, Jeffrey J, Ajuong, Elijah, Freitag, Camille Port Orford cedar (Chamaecyparis lawsoniana) has a reputation for being resistant to fungal attack, but much of the work to support this premise used older growth material (80-100 yr old). Given the tendency for the heartwood from the second growth of some species to be less durable, we evaluated the decay resistance of Port Orford cedar heartwood from 12 trees in laboratory soil block tests using Postia placenta and Gloeophyllum trabeum as the test fungi. Weight losses ranged from as little as 1.1 to more than 60% with most blocks experiencing weight losses between 11 and 24%. Heartwood was resistant to attack by G. trabeum but proved to be very susceptible to P. placenta and was only moderately resistant to this species. These results suggest that the durability rating of second-growth Port Orford cedar merits a re-evaluation. Title: Decay resistance and extractive content of second-growth Port Orford cedar (Chamaecyparis lawsoniana) wood Author: Morrell, Jeffrey J, Ajuong, Elijah, Freitag, Camille Port Orford cedar (Chamaecyparis lawsoniana) has a reputation for being resistant to fungal attack, but much of the work to support this premise used older growth material (80-100 yr old). Given the tendency for the heartwood from the second growth of some species to be less durable, we evaluated the decay resistance of Port Orford cedar heartwood from 12 trees in laboratory soil block tests using Postia placenta and Gloeophyllum trabeum as the test fungi. Weight losses ranged from as little as 1.1 to more than 60% with most blocks experiencing weight losses between 11 and 24%. Heartwood was resistant to attack by G. trabeum but proved to be very susceptible to P. placenta and was only moderately resistant to this species. These results suggest that the durability rating of second-growth Port Orford cedar merits a re-evaluation. Close

• 3. [Article] Production of fungal protoplasts from selected wood-degrading fungi

  Studies of the effects of various chemicals on fungal growth are difficult to perform on filamentous fungi because of the difficulty of observing the protoplasm through the rigid hyphal wall, and because ...

  Citation × Citation Citation Abstract Copy Title: Production of fungal protoplasts from selected wood-degrading fungi Author: Rui, Chen, Morrell, Jeffrey J. Studies of the effects of various chemicals on fungal growth are difficult to perform on filamentous fungi because of the difficulty of observing the protoplasm through the rigid hyphal wall, and because most activity occurs in the region near the hyphal tip. However, hyphae can be exposed to certain enzymes that degrade the cell walls, producing protoplasts. There are few reports of protoplast production from economically important wood decayers. In this report, protoplasts were produced from hyphae of the common wood-degrading fungi Phanerochaete chrysosporium, Postia placenta, Gloeophyllum trabeum, and Trametes versicolor with a commercially prepared mixture of cell-wall degrading enzymes (Novozyme 234). Protoplasts were more readily produced from young hyphae; however, regeneration was better with older hyphae. Magnesium sulfate and mannitol (0.5 M) performed comparably well as osmotic stabilizers. Title: Production of fungal protoplasts from selected wood-degrading fungi Author: Rui, Chen, Morrell, Jeffrey J. Studies of the effects of various chemicals on fungal growth are difficult to perform on filamentous fungi because of the difficulty of observing the protoplasm through the rigid hyphal wall, and because most activity occurs in the region near the hyphal tip. However, hyphae can be exposed to certain enzymes that degrade the cell walls, producing protoplasts. There are few reports of protoplast production from economically important wood decayers. In this report, protoplasts were produced from hyphae of the common wood-degrading fungi Phanerochaete chrysosporium, Postia placenta, Gloeophyllum trabeum, and Trametes versicolor with a commercially prepared mixture of cell-wall degrading enzymes (Novozyme 234). Protoplasts were more readily produced from young hyphae; however, regeneration was better with older hyphae. Magnesium sulfate and mannitol (0.5 M) performed comparably well as osmotic stabilizers. Close

• 4. [Article] Relationship between incipient decay, strength, and chemical composition of Douglas-fir heartwood

  A new laboratory technique to simulate the initiation of wood decay and to assess the effects of incipient decay on material properties is described. Douglas-fir heartwood specimens were exposed to brown-rot ...

  Citation × Citation Citation Abstract Copy Title: Relationship between incipient decay, strength, and chemical composition of Douglas-fir heartwood Author: Morrell, Jeffrey J., Winandy, Jerrold E. A new laboratory technique to simulate the initiation of wood decay and to assess the effects of incipient decay on material properties is described. Douglas-fir heartwood specimens were exposed to brown-rot (Postia placenta and Gloeophyllum trabeum) fungi for various periods. Bendlng properties were determined by nondestructive and destructive tests, and chemical composition of specimens was analyzed. Weight losses of 1 to 18% were linearly related to strength losses of 5 to 70%. Wood strength loss by brown-rot fungi was also closely related to degradation of hemi-cellulosic components. Hemicellulose sidechains, such as arabinose and galactose, were degraded in the earliest stages of decay; main-chain hemicellulose carbohydrates, such as mannose and xylose, were degraded in the later stages. Changes in glucose content, a measure of residual cellulose, were minimal. Our technique was effective for establishing and assessing brown-rot decay. Title: Relationship between incipient decay, strength, and chemical composition of Douglas-fir heartwood Author: Morrell, Jeffrey J., Winandy, Jerrold E. A new laboratory technique to simulate the initiation of wood decay and to assess the effects of incipient decay on material properties is described. Douglas-fir heartwood specimens were exposed to brown-rot (Postia placenta and Gloeophyllum trabeum) fungi for various periods. Bendlng properties were determined by nondestructive and destructive tests, and chemical composition of specimens was analyzed. Weight losses of 1 to 18% were linearly related to strength losses of 5 to 70%. Wood strength loss by brown-rot fungi was also closely related to degradation of hemi-cellulosic components. Hemicellulose sidechains, such as arabinose and galactose, were degraded in the earliest stages of decay; main-chain hemicellulose carbohydrates, such as mannose and xylose, were degraded in the later stages. Changes in glucose content, a measure of residual cellulose, were minimal. Our technique was effective for establishing and assessing brown-rot decay. Close

• 5. [Article] Effects of environmental factors on decay rates of selected white- and brown-rot fungi

  This is the publisher’s final pdf. The published article is copyrighted by the Society of Wood Science and Technology and can be found at: http://www.swst.org/wfs/journal.html. The author has paid this ...

  Citation × Citation Citation Abstract Copy Title: Effects of environmental factors on decay rates of selected white- and brown-rot fungi Author: Morrell, Jeffrey J., Gonzalez, June Mitsuhashi This is the publisher’s final pdf. The published article is copyrighted by the Society of Wood Science and Technology and can be found at: http://www.swst.org/wfs/journal.html. The author has paid this publisher's Open Access fee. Title: Effects of environmental factors on decay rates of selected white- and brown-rot fungi Author: Morrell, Jeffrey J., Gonzalez, June Mitsuhashi This is the publisher’s final pdf. The published article is copyrighted by the Society of Wood Science and Technology and can be found at: http://www.swst.org/wfs/journal.html. The author has paid this publisher's Open Access fee. Close