Your search resulted in 108 documents. Displaying 25 entries per page.
Preliminary study of the fungicidal and structural variability in copper naphthenates and naphthenic acids
1996 - IRG/WP 96-30114
Copper naphthenates, an oil-borne wood preservative listed by the American Wood-Preservers' Association (AWPA), is manufactured by complexing copper(II) with naphthenic acids. Prior to AWPA listing as a wood preservative, field experiments showed that copper naphthenates generally had good stability and were active against wood-destroying organisms. Recently, however, there have been reports ...
T Schultz, D D Nicholas, L L Ingram Jr, T H Fisher
Physical properties of ß-1,4-Xylanase produced by Postia (=Poria) placenta: Implications for the control of brown rot
1987 - IRG/WP 1318
The degradation of hemicelluloses is an early event in wood decay by brown-rot fungi. An understanding of the physical properties of hemicellulases may suggest target mechanisms for the development of new control agents. Endo-b-1,4-xylanase was partially purified by column chromatography from wood decayed by Postia (= Poria) placenta. The enzyme was extremely resistant to denaturing conditions; no...
J A Micales, F Green III, C A Clausen, T L Highley
Determination of the preventive efficacy against wood destroying basidiomycetes fungi, EN V 839 - CEN/TC 38 WG 9
1993 - IRG/WP 93-20015
The WG 9 of CEN TC/38 has presented to EC a mycological test to assess efficacy of preservatives applied by surface process. This method is now an experimental standard (EN V 839) which has to be approved by the different european delegations. The following paper is not the standard as it has been proposed but is a presentation of the principle of the method. The experimental standard specifies a ...
D Dirol
The influence of crystalline and amorphous cellulose on extracellular hydrogen peroxide production by brown-rot fungi
1991 - IRG/WP 1482
The production of hydrogen peroxide (H2O2) has been suggested to play a key role in the degradation of wood by wood-rotting fungi. The production of extracellular hydrogen peroxide was studied by a quantitative method which detects the oxidation of the 2,2-azinobis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) by H2O2 and horseradish peroxidase (HRP) in liquid culture medium. The carbon sources u...
A-C Ritschkoff, L Viikari
Temperature influence on the growing velocity and cellulolytic activities of Poria placenta strains from several locations
1986 - IRG/WP 2263
The differences observed on the FPRL 280 Poria Placenta strain at several Research European Laboratories for determining up the fungicide effectiveness of wood preservative has carry us to do a comparative study about the cellulolytic activity and growth velocity of each of this strains at different temperatures (22, 24 and 28°C). The results show significative differences when the temperature is...
A M Navarrete, M T De Troya
A preliminary study on the feasibility of substituting the soil culture medium in soil block tests
1984 - IRG/WP 2209
In this work the possibility was studied of substituting the soil culture medium in preservative screening methods. The conclusions are that another type of material, Sphagnum moss, can be used with advantages, but that some more information is still needed to give a real idea regarding the differences caused by the substrate tested....
J C Moreschi
Some physiological characteristics of a non-degradative strain of Postia (=Poria) placenta
1988 - IRG/WP 1341
The decay capacity of 14 strains of the brown-rot fungus Postia (= Poria) placenta was determined using soil-wood block tests. One isolate was identified as being unable to degrade wood and was determined to be monokaryotic. It retained the ability to produce extracellular carbohydrate-degrading enzymes, although regulation of certain enzymes was atypical under certain cultural conditions. It prod...
J A Micales, T L Highley
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
The leachability, biological resistance, and mechanical properties of wood (Pinus sylvestris L.) treated with CCA and CCB preservatives
1999 - IRG/WP 99-30207
Scots pine (Pinus sylvestris L.) specimens treated with CCA and CCB preservative solutions (1.0%) were subjected to several fixation processes and leached elements from the specimens were determined. In addition, the specimens exposed to different fixation temperatures were subjected to soil-block test using two brown-rot fungi and one white-rot fungus in order to investigate the effects of fixati...
S N Kartal
Localization of oxalate decarboxylase in the brown-rot fungus Postia placenta
1996 - IRG/WP 96-10161
Oxalate decarboxylase, the enzyme that breaks oxalic acid down into formic acid and carbon dioxide, was recently detected in mycelial extracts of the brown-rot fungus Postia placenta. Differential centrifugation was used to demonstrate that the enzyme is loosely associated with the hyphal surface. Enzyme activity can be removed by washing the hyphae with a low pH buffer. Only low levels of activit...
J A Micales
Report on the status of collaborative experiments within the Sub-group on Basidiomycete tests
1983 - IRG/WP 2194
This report summarises the results of co-operative work carried out within the Sub-Group on Basidiomycete tests up to December 1982. The principle findings are recorded in the Conclusions Section. Work intended between IRG-13 in Turkey and IRG-14 in Australia is cited under Future Programme. An Annex provides a response sheet for existing and new participants to notify their contributions....
A F Bravery
About the relations between the natural durability of some tropical species and their extractives content
1983 - IRG/WP 1208
G R Y Déon
Progress report on collaborative experiments on testing with basidiomycetes
1982 - IRG/WP 2184
The present Document reviews results provided by participants as at 1 May 1982 and draws preliminary conclusions....
A F Bravery
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
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
Suppression of aerial hypha formation by spent culture filtrate of a non-degradative strain of Postia placenta
1991 - IRG/WP 1498
ME20, a wild-type monokaryotic strain of the brown-rot fungus Postia placenta, does not cause significant weight losses in standard soil-wood block decay tests and fails to form aerial hyphae in liquid and agar culture. This abnormal morphological feature may be caused by the same aberrant physiology that prevents the strain from degrading wood efficiently. ME20 releases elevated levels of the aut...
J A Micales
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
Identification of terminal structures in cellulose degraded by the brown-rot fungus Postia placenta
1989 - IRG/WP 1389
To gain insight into the biochemical mechanism employed by brown-rot fungi to depolymerize cellulose, we identified the end-groups of chemically pure cellulose that had been depolymerized by the brown-rot fungus, Postia placenta. The depolymerized cellulose was acid hydrolyzed and the anion fractions isolated by ion chromatography. Sugar acids were identified by gas chromatographic and mass spectr...
T K Kirk, T L Highley, R E Ibach, M D Mozuch
Biosynthesis of ß-Glucan microfibrils by cellular fractions from brown-rot fungus Postia placenta (MAD-698 and ME-20) and white-rot fungus Schizophyllum commune (MAD-619)
1993 - IRG/WP 93-10025
In this study, we compared the brown rot fungus Postia placenta (MAD-698 and ME-20) with the white rot fungus Schizophyllum commune (MAD-619) to determine the location and distribution of glucan synthetase. We also measured the soluble protein content in subcellular fractions obtained by differential centrifugation MAD-698 is a degradative isolate, but ME-20 and MAD-619 do not produce significant ...
S C Croan, T L Highley