Your search resulted in 80 documents. Displaying 25 entries per page.
Prevention of brown-rot decay by chelators
1992 - IRG/WP 92-1540
In this work the brown-rot decay was shown to be prevented by chelating the endogenous metals existing in wood by using organic or inorganic chelators or iron-binding siderophores. The fungal growth and decaying ability were significantly decreased by the chelating treatments of the solid wood-based culture medium and pine wood pieces, respectively. The transition metals existing in native wood ar...
L Viikari, A-C Ritschkoff
Effect of sterilization method on germination of spores of wood decay fungi observed by contact agar block method
1978 - IRG/WP 2117
Previous studies of germination of spores of wood decay fungi on wood have generally concluded that method of wood sterilization has little significant effect on germination response. This study expands the numbers of test fungi as well as number of sterilization methods employed to determine the influence of sterilization method on spore germination response of decay fungi. Germination was assess...
E L Schmidt, D W French
Effect of asphyxiation on wood decay fungi treated
with argon and nitrogen gas
2002 - IRG/WP 02-10452
The effects of low-oxygen conditions, achieved with either argon or nitrogen gas, on the viability of wood decay fungi Coniophora puteana, Antrodia vaillantii and Trametes versicolor, cultivated on PDA medium and infected wood samples, were examined. The fungal cultures were exposed to low oxygen concentration (below 10 ppm) for one to five weeks in hermetically sealed vessels. Anoxic treatment di...
C Tavzes, F Pohleven, M Janisek, R J Koestler
Some observations on miniaturised soil/block tests
1988 - IRG/WP 2317
Results are presented for miniaturised soil/block tests carried out in 120 ml capacity glass jars. The four test fungi (Coniophora puteana, Coriolus versicolor, Gloeophyllum trabeum and Poria placenta) reacted differently to different moisture regimes established by varying the soil moisture content. Acceptable levels of decay were achieved by the three brown rot fungi with soil at 110% whc; howev...
J K Carey
A laboratory evaluation of the susceptibility to biological attack of glued laminated pine timber
1991 - IRG/WP 2387
In the scope of a research programme concerning the use of maritime pine (Pinus pinaster) to produce glued laminated timber structures in Portugal, the natural durability of this material was checked by using laboratory test methods. An European standard, EN 113, was used to test durability against basidiomycetes and a test method developed at LNEC for termites was adapted for this purpose. From t...
L Nunes, H Cruz
Involvement of hydrogen peroxide in wood decay by brown-rot and white-rot fungi
1985 - IRG/WP 1256
To gain further understanding of the role of H2O2 in wood degradation by brown- and white-rot fungi, we studied the following: (a) extracellular H2O2 production, (b) effect of various hydroxyl radical (·OH) and singlet O2 (1O2) quenching agents on wood and cellulose degradation, (c) intracellular H2O2 production and catalase activity, and (d) cytochemical localization of H2O2 with diaminobenzidin...
T L Highley, L L Murmanis
Experience with an industrial scale-up for the biological purification of CCA-treated wood waste
1997 - IRG/WP 97-50095
The biological purification of CCA-treated wood waste was tested in co-operation of the BFH and the Italian impregnation plant SoFoMe. Chipped poles were infested with the chromium and arsenic tolerant brown-rot fungus Antrodia vaillantii which can transform in the laboratory ca. 90% of the chromium and arsenic into watersoluble salts. These can be leached to 100-200 ppm residual metal content. Th...
H Leithoff, R-D Peek
Natural durability of eight tropical hardwoods species from Africa
2005 - IRG/WP 05-10563
Current forest inventory results reveal that there are more than 700 hundred-hardwood species in tropical forests, of which less than 10 percent are harvested and used for commercial purposes. The increased use of lesser-known species can decrease the pressure on current commercial species, increase the value of the forest and lead to better management practices. However basic information on physi...
P Nzokou, K Wehner, D P Kamdem
Effect of mineral wools on growth and decay capacities of Serpula lacrymans and some other brown-rot fungi
1991 - IRG/WP 1481
The influence of stone wool and glass wool on growth and decay capacities of Serpula lacrymans and some other brown-rot fungi was studied. Mass losses of pine wood caused by Serpula lacrymans and Gloeophyllum trabeum were increased when stone wool was present. Glass wool had no influence on mass losses. Coniophora puteana, Serpula lacrymans and Gloeophyllum trabeum grew into stone wool and destroy...
L Paajanen, A-C Ritschkoff
Triazoles: Synergism between propiconazole and tebuconazole
1995 - IRG/WP 95-30092
The synergistic action of the two triazoles propiconazole and tebuconazole against wood rotting fungi can clearly be demonstrated by determination of toxic values according to Standard EN 113. The results show that by combining both triazoles a better balanced spectrum of activity can be achieved. The reduction of the toxic values against the white rot fungus Coriolus versicolor (toxic values of t...
H-U Buschhaus, A R Valcke
Effects of a formaldehyde and sulphur dioxide treatment on decay and mechanical properties of aspen waferboard
1983 - IRG/WP 3242
Aspen wafers were sequentially treated under vacuum with formaldehyde and sulfur dioxide gas and pressed into waferboard bonded with powdered phenol formaldehyde resin. Decay resistance and strength properties were determined before and after simulated weathering. The water resistance of the phenol bonding system was lost in board made from the gas-treated wafers. This white rot fungus Coriolus ve...
E L Schmidt
An evaluation of CCA, CCB and CCP preservatives using a "sandwich test"
1991 - IRG/WP 2370
The last two years has seen some important changes in standards and preservative types used in Scandinavia, which have led to a wider choice for specifiers. In order to identify those treatments suitable for replacement or reinforcement of decayed constructional timbers, it was felt necessary to modify the standard EN 113 test. Impregnated blocks were sandwiched between two untreated blocks, previ...
A P Koch, L B Sheard
Evaluation of substituted isothiazolone as a potential new wood preservative
1984 - IRG/WP 3306
Laboratory decay tests were carried out with isothiazolone (4,5-dichloro-2-n-octyl-4-isothiazolone-3-one) treated wood. This compound was found to be extremely effective against three common wood decaying brown-rot fungi, exhibiting toxic threshold values in the range of 0.37 to 0.50 kg/m³. For the white-rot fungus, Coriolus versicolor, the toxic threshold values for treated pine and sweetgum wer...
D D Nicholas, A F Preston, D E Greenley, S V Parikh
A technique for determinging the efficacy of wood preservatives for partially treated timber
1988 - IRG/WP 2322
A technique is described for determining the efficacy of wood preservatives either for certain wood species where a full penetration cannot be achieved by normal vacuum-pressure methods or for more permeable species to look at efficacy of treated zone in preventing decay of an untreated core. Both sapwood and heartwood planks of spruce (Picea abies) and pine (Pinus sylvestris) were treated by CCA ...
A J Nurmi
Investigation on different variation factors in the results of mycological test and means to reduce and avoid them
1986 - IRG/WP 2264
In order to clarify the causes of the dispersion observed in the results obtained with mycological tests made in accordance with standard EN-113, different factors assumed to be sources of the variations were studied. These included the moisture content of the test samples during the test, the influence of certain technological properties of the wood, the virulence of the fungus strains, the metho...
D Dirol
In vitro sporulation of selected wood decay fungi
1978 - IRG/WP 190
Basidiospores produced axenically without laborious attention in the laboratory are useful in studies of wood decay initiation. Such spores presumably approach those collected from natural sporophores in size and germinability (Morton, 1964). Production of spores in vitro by inversion of cultures grown on 2% malt extract agar in deep glass dishes (100x80 mm²) has been the preferred method (Morton...
E L Schmidt, D W French
Contradiction between uptake of preservative in practical situation and laboratory testing
1992 - IRG/WP 92-2392
By brush treatment water- and solvent-based products were applied on boards of Scots pine and Norway spruce to achieve an uptake of 100 and 200 g/ml. In addition the scope of work to achieve the required uptake of preservative was determined under practical conditions for both product groups. EN 113 (RAL-GZ 830) tests were carried out to test the biological efficacy of products. After 18 months ex...
R Gründlinger, O Janotta, M Melzer
A serial exposure technique for estimating probable service life of treated timber
1978 - IRG/WP 2111
This paper briefly describes part of our preliminary work aimed at developing a test procedure that culd be adopted as a standard method. A detailed version of the work has been submitted for formal publication. In both papers, the aim is to promote interest in extended laboratory testing of wood preservatives. It is believed that this work may provide the basis of a laboratory test procedure from...
J A Butcher
Fenton's reagent as a modification tool in brown-rot decay
1996 - IRG/WP 96-10155
A biomimetic approach was used to clarify the role and importance of the Fenton-type reaction in the carbohydrate degradation by brown-rot fungi. Spruce sawdust and microcrystalline cellulose were modified in the H2O2/Fe(II) treatment. The degree of hydrolysis of the pretreated spruce sawdust was clearly increased with the complete cellulase (Econase), purified endoglucanase from Trichoderma reese...
M Rättö, A-C Ritschkoff, J Buchert, L Viikari
Lethal temperature for some wood-destroying fungi with respect to eradication by heat treatment
1984 - IRG/WP 1229
The lethal heat dosis as a function of temperature and time of exposure has been tested for mycelium and for wood infested by three strains of Serpula lacrymans and by Coniophora puteana, Poria monticola, Paxillus panuoides, Gloeophyllum trabeum and Gloeophyllum sepiarium. Even for Serpula lacrymans, which is well known for its sensivity to heat treatment, 30 min at 55°C were necessary to kill th...
M Miric, H Willeitner
Production of exraxellular hydrogen peroxide and oxalic acid by brown-rot fungus Poria placenta
1995 - IRG/WP 95-10112
Hydrogen peroxide and oxalic acid have been suggested to be essential in the degradation of wood carbohydrates by brown-rot fungi. Hydrogen peroxide has been suggested to be one of the diffusible low molecular weight agents produced by brown-rot fungi for the degradation of wood carbohydrates by generating highly active radicals. The production of hydrogen peroxide and oxalic acid by Poria placent...
A-C Ritschkoff, M Rättö, J Buchert, L Viikari
Microbial decomposition of salt treated wood
1993 - IRG/WP 93-50001-22
Specialized microorganisms which are able to convert fixed inorganic preservatives from treated wood into water soluble components are investigated. A number of brown rot fungi like Antrodia vaillantii have been isolated from cases of damage and examined under unsterile conditions with CCA-, CCB-, CCF- and CC-treated wood at retention levels of at least 50% higher than recommended for wood in grou...
R-D Peek, I Stephan, H Leithoff
Detection of a brown-rot fungus using serological assays
1986 - IRG/WP 1305
Polyclonal antisera produced to Poria placenta (Fr.) Cooke were used in two tests to qualitatively assay for the fungus. Fungal hyphae were fixed to slides and fluorescent antibody (FA) techniques used to visualize the hyphae under the microscope. Fluorescence of non-Poria fungi, when present, could be reduced but not eliminated by cross-absorbing the sera with these fungi. The antisera was also u...
B Goodell, J Jellison
Feasibility of using biological control agents to arrest and prevent colonization of Douglas fir and southern pine by decay fungi
1988 - IRG/WP 1345
The use of microfungi to control basidiomycetous decay has been evaluated in Europe for many years, where it has produced mixed results against Lentinus lepideus Fries, the fungus presumed to be the major cause of decay in Scots Pine poles. In the United States, remedial decay control has been largely chemical, with little use of alternative decay control strategies. Increasing restrictions on che...
J J Morrell, C M Sexton
Laboratory studies on the antagonistic properties of Scytalidium spp to Basidiomycetes with regard to biological control
1981 - IRG/WP 1130
This investigation was initiated to study the progress of the antagonism against various opposing species of basidiomycetes. The action of the FY strain of the Scytalidium spp isolated by Ricard and Bollen (1968) was compared with that of new isolates of Scytalidium spp against isolates of wood decaying fungi from British sites, specifically Lentinus lepideus the most common basidiomycete causing ...
P I Morris, D J Dickinson