Your search resulted in 333 documents. Displaying 25 entries per page.
Regulation of hyphal sheath formation iron-chelator production by the brown rot fungi Gloeophyllum trabeum and Postia placenta
1994 - IRG/WP 94-10074
Hyphal sheath formation and iron-chelator production by liquid cultures of the brown rot fungi Gloeophyllum trabeum and Postia placenta were monitored over time. The effects of incubation at various temperatures, pH's and concentrations of iron, manganese and nitrogen were determined. Hyphal sheath production was observed microscopically and quantified with JAVA video analysis. The hyphal...
Y Chen, J Jellison
Breakdown of cellulose derivatives by cellulolytic enzymes. I. Action of fungal ß-glucosidases toward substituted PNP ß-D-glucopyranosides
1998 - IRG/WP 98-10281
The action of fungal ß-glucosidases on the methyl derivatives of p-nitrophenyl (PNP) ß-D-glucopyranoside, which were regioselectively substituted at 0-2, 0-3, 0-4 and 0-6 positions was studied. Several ß-glucosidases from brown-rot, white-rot, and soft-rot fungi and almond were used for the study. These ß-glucosidases did not act on the 2, 3, and 4-0-methyl derivatives, while the 6-0-methyl on...
T Nishimura, I Momohara, M Ishihara
Improved preservative penetration of spruce after pre-treatment with selected fungi. I. Fungal pre-treatment of pole sections
1998 - IRG/WP 98-40117
European spruce logs were pre-treated with either Phanaerochete chrysosporium, Dichomitus squalens, Trichoderma viride and Trichoderma aureoviride for incubation periods of between 1-4 weeks prior to pressure treatment with creosote in a commercial treatment plant and analysed for strength and creosote uptake (see part II Tucker et al.). A method to pre-treat logs was optimised. The pole sections ...
B Rosner, K Messner, E J B Tucker, A Bruce
The suitability of isothiazolone microemulsions as long term wood preservatives
1997 - IRG/WP 97-30150
Microemulsion formulations of 4,5 dichloro-2-n-octyl-4-isothiazolin-3-one were investigated to determine the leaching potential of these formulation types as well as their efficacy against decay fungi. These patented low leaching formulations exhibited good anti fungal efficacy in standard tests combined with minimal leaching of the active ingredient from the wood. The data suggests that the excel...
B M Hegarty, Bing Yu, L E Leightley
Artificial weathering exposure as an alternative for standard ageing according to EN 84 (leaching) and EN 73 (evaporation)
2002 - IRG/WP 02-20254
In order to verify potential weaknesses of wood preservatives fungal tests are carried out after ageing of wood preservative treated test blocks. The European standard EN 599 as a framework for efficacy assessment of wood preservatives includes the use of two ageing methods prior to fungal testing, namely a leaching method (EN 84) and an evaporation method (EN 73). The European research project "F...
J Van Acker, M Grinda, D J Dickinson
Revised South African standards for wood preservation: Protocols for approval of wood preservatives
1995 - IRG/WP 95-20072
In 1994 the South African timber treatment industry completed its revision of the South African Bureau of Standards (SABS) Code of Practice for the preservative treatment of timber. These revisions were undertaken in parallel with changes to the SABS specifications for preservative treated timber. As a result of shortcomings in the previous wood preservative classification system which was based o...
D Conradie, P Turner, W E Conradie, A D Currie, I S J Burger
Effect of origin and orientation of Radiata pine substrates on the development of fungal degrade
2000 - IRG/WP 00-30221
The objective of this study was to determine the influence of different radiata pine substrates on colonisation by sapstain fungi. Freshly-cut branch wood, stem wood and sawn lumber were used to prepare test samples with the largest wood surface area showing a transverse, radial or tangential face. Test samples were evaluated against sapstain fungi using a rapid laboratory antisapstain screening m...
B Kreber, D R Eden, C M Chittenden, B Carpenter, J G Van der Waals
Possibility and problems of characterizing treated wood after service with regard to disposal
1993 - IRG/WP 93-50006
For the disposal of wood waste under ecological conditions, information about its hazardous potential and the logistic aspects for its handling is needed. The main criterion to evaluate the hazardous potential besides the determination of the type and quantity of active ingredients in the wood will be the degree of mixture with different treated or untreated timber. Assortments can be homogeneous ...
A Voss, H Willeitner
Termite resistance classification of some tropical and temperate species based on the laboratory choice test results against formosan termite, Coptotermes formosanu
2004 - IRG/WP 04-20291
The results of classification of termite durability were varied. We carried out
laboratory evaluation of the classification of termite durability on various species by
the choice test against formosan termite, Coptotermes formosanus. We classified five
grades (very sensitive to very resistant). According to our results, azobe, ipe, keruing,
intsia, kapur, yellow meranti, jarraah, malas, cypres...
K Suzuki
Differentiation of Scots pine heartwood and sapwood by near infrared spectroscopy
2003 - IRG/WP 03-10459
In Scandinavia Scots pine heartwood has, in recent years, gained popularity as material for external structures exposed to moderate risk of decay. As non-durable sapwood surrounds the heartwood in pine trunks it is of crucial importance to separate this wood from the heartwood during log processing into heartwood products. Heartwood and sapwood can be differentiated by visual evaluation of colour ...
P O Flæte, E Ystrøm Haartveit
Effects of air-seasoning on fungal colonization and wood strength of Douglas fir poles
1987 - IRG/WP 1315
Air seasoning economically reduces the moisture content of Douglas fir poles before pressure treatment with preservatives. Advanced decay in poles in service has resulted when decay fungi (Basidiomycetes) colonized poles during air-seasoning and survived the treatment process. These problems have led to recommendations to severely limit this practice. To determine the role of these fungi in peeled...
J J Morrell, M E Corden, R D Graham, B L Kropp, P Przybylowicz, S M Smith, C A Sexton
The influence of staining fungi on the decay resistance of wood treated with alkylammonium compounds
1984 - IRG/WP 3308
Although found to be very effective in laboratory tests, alkylammonium compounds (AAC's) have failed to perform as well in field stake tests. Examination of leachability showed that this was not the cause. The present study investigated the possibility that staining fungi, (which have been observed to rapidly infect the field stakes), degrade the AAC wood preservative. Soil-blocks were tr...
J N R Ruddick
Comparison of the in-ground performance of pigment emulsified creosote (PEC) and high temperature creosote (HTC)
2000 - IRG/WP 00-30217
A long-term field trial was conducted in Australia to compare the in-ground performance of two oil-borne preservative formulations, conventional high temperature creosote (HTC) and a modified creosote formulation, pigment emulsified creosote (PEC). Three retentions (50, 100 and 200 kg/m³) were targeted for each formulation. An additional retention of PEC formulation (308 kg/m³), which contained ...
J W Creffield, H Greaves, N Chew, N K Nguyen
International standards - can we make them simple? Stage 2: Reflection arising from the discussion at IRG 27
1996 - IRG/WP 96-20103
For the purpose of the ISO FAST TRACK project on preventive wood protection and durability, one shall refer to the 3 following stages:
Hazards: (for wood in service), a review of biological agencies defining the scope;
Exposure: a review of local, geographical parameters influencing the virulence of biological agencies towards wood in service (i.e climate indexes);
Risks: as a combination of ha...
G Ozanne
Fungal detoxification of organotin biocides
1985 - IRG/WP 1258
The ability of a range of wood decaying fungi to inactivate bis(tri-n-butyltin) oxide (TnBTO) in the extracellular growth medium, in stationary liquid culture was determined. A distinction between the ability to tolerate the fungicide and to inactivate it was made: the white-rot organism Coriolus versicolor being the most efficient inactivator. In an attempt to determine the extracellular agents r...
P S Belford, D J Dickinson
Possible durability transfer from durable to non durable wood species. The study case of teak wood
2001 - IRG/WP 01-10392
Teakwood is well known for its excellent natural durability, mostly due to its high proportion of extracts. Amongst these extracts, quinones, and more precisely some naphtoquinones (such as lapachol) and anthraquinones (such as tectoquinone) appear to play a crucial role in the resistance to wood decay organisms. At a laboratory scale, sawdust from malaysian teak heartwood has been extracted under...
M-F Thévenon, C Roussel, J-P Haluk
Comparison of the anti-fungal efficacy of Cobra with drill perforation on oscillating pressure treated spruce transmission poles -Laboratory test
1988 - IRG/WP 3469
A laboratory method for measuring the depth of penetration of the fungicidal concentrations effective against basidiomycetes (brown rot) was developed. The tests on CCB oscillating pressure treated spruce transmission poles have shown that the depth of salt penetration can be increased by about 10 mm by a drill perforation before the impregnation. An even better penetration is reached, however, if...
E Graf, B Zgraggen
A study of fungal biodeterioration in unseasoned, packaged hem-fir lumber
1978 - IRG/WP 2116
This study was undertaken to determine the extent of biodeterioration that could occur within British Columbia (BC) prior to the export of packaged Canadian Lumber Standard Hem-Fir (Tsuga heterophylla, Abies amabilis and small amounts of Abies grandis). By examining the anti-stain treatments received by the lumber and identifying and characterizing the organisms responsible for the biodeterioratio...
P W Perrin, A J Cserjesi
Resistance of acrylic paints on wood against growth of the rot fungus Dacrymyces stillatus
1990 - IRG/WP 2345
In the last few years the presence of the rot fungus Dacrymyces stillatus has been repeatedly confirmed in external wood panels, particularly from wood painted with water based paints. A laboratory method for testing of the fungal resistance of paint films on wood has been developed.This method has been used to test the efficacy of the fungicides Parmetol DF 18 and Parmetol HF 25 against attack by...
J Bjurman
Occurrence and importance of various types of fungal and bacterial decay in CCA-treated horticultural pine posts in New Zealand
1984 - IRG/WP 1234
A detailed microscopical examination has been carried out on samples taken from CCA-treated pine posts exposed in horticultural soils. The following decay types were observed: white rot, brown rot, soft rot, tunnelling bacteria, cavitation bacteria, and bacterial erosion. The occurrence and importance of the various decay types between different regions, and plots within a specific region, varied ...
T Nilsson
A biochemical explanation for the observed patterns of fungal decay in timber
1980 - IRG/WP 1111
Experiments designed to compare the degree of localization of the cellulase enzymes of some white, brown and soft rot organisms are described. The site and nature of binding of the enzymes is discussed. The technique is ellution of mycelium grown in liquid culture with a variety: of agents including acetate buffer, carboxymethyl cellulose solution, borate/glycerol buffer and urea. The mycelium was...
N B Green, D J Dickinson, J F Levy
International comparison of three field methods for assessing the in-ground resistance of preservative-treated and untreated wood to termites and fungal decay – Summary of observations after five years
2003 - IRG/WP 03-20261
Results are presented from a five-year study conducted in five locations in Australia, Thailand and the USA. Three methods of exposure were assessed (below-ground, graveyard and ground contact) for evaluating the in-ground termite and decay resistance of Pinus radiata D. Don sapwood stakes that had been vacuum pressure impregnated with CCA (Type C) and ACQ (Type D) each at two nominal retentions (...
M Lenz, J W Creffield, T A Evans, B M Kard, C Vongkaluang, Y Sornnuwat, A F Preston
Imaging fungal deterioration of wood using x-ray microtomography
1997 - IRG/WP 97-10240
Nondestructive tomographic images of solid Southern yellow pine (SYP) wood and SYP during deterioration by wood decay fungi were obtained by using a new class of synchrotron X-ray computed microtomography (CMT). The CMT images will provide information about spatial relationship between degrading fungi and wood structures. Wood samples were scanned with synchrotron-generated X-rays at high resoluti...
B Illman, B A Dowd
Effects of the specimen position on fungal colonisation and wood decay by en 113 test fungi
1998 - IRG/WP 98-20136
For testing wood preservatives according to EN 113 it is common practice to plant the test blocks on neutral supports in order to prevent (1) a diffusion of chemicals into the agar medium and (2) an excessive moistening of the specimens. The procedure was employed in EN 350-1 for testing the natural durability of solid wood.
It turned out to be of problematic nature because of the individual requ...
G Kleist, M-T Lenz, R-D Peek
Fungal decay resistance of Rubber wood treated with heartwood extract of Rosewood
2005 - IRG/WP 05-30367
Alcoholic extract of Dalbergia latifolia heartwood was studied for its toxicity towards wood decaying fungi. Rubber wood blocks were treated with this extract to three different retention levels (0.1%, 0.2% & 0.5%) and the treated wood blocks were assessed for their resistance towards two white rot and two brown rot fungi. Treated blocks showed improved resistance over the control blocks. At 0...
A K Sethy, H C Nagaveni, S Mohan, K T Chandrashekar