Your search resulted in 425 documents. Displaying 25 entries per page.
Extracellular osmiophilic particles in connection with brown rot and white rot
1982 - IRG/WP 1157
The way of attack on Pine woodblocks of two brown-rot fungi (Fomitopsis pinicola, Coniophora puteana) differing in their cellulase activities, and one white-rot fungus (Trametes hirsuta) has been investigated by transmission electron microscopy. Even at early stages of decay, osmiophilic particles were found with all the fungi investigated. In the brown-rotted wood, the osmiophilic particles occur...
K Messner, H Stachelberger
Production, function and neutralization of oxalic acid produced by the dry rot fungus and other brown rot fungi
1987 - IRG/WP 1330
The formation of oxalic acid by the wood-destroying fungi causing brown rot, is found to be the key which by hydrolysing the hemicellulose brings the cellulose in the tracheid wall in contact with the cellulase enzymes and yeld watersoluble sugars leaving only a lignin skeleton. To control the pH in the substrate the excess oxalic acid is precipitated to water insoluble calcium oxalate by the dry ...
J Bech-Andersen
The role of oxygen and oxygen radicals in one-electron oxidation reactions mediated by low-molecular weight chelators isolated from Gloeophyllum trabeum.markup
1994 - IRG/WP 94-10086
The KTBA assay for determination of one-electron oxidation activity was used to assay reactions of low-molecular weight chelators isolated from the brown rot fungus Gloeophyllum trabeum. The assay, performed either under air or nitrogen showed that molecular oxygen was an important factor in chelator-mediated oxidation reactions. A reduction in oxidative activity was observed when superoxide dismu...
Jun Lu, B Goodell, Jiang Liu, A Enoki, J Jellison, H Tanaka, F Fekete
Hydrolysis of bordered pits during colonization of conifers by brown-rot fungi
1995 - IRG/WP 95-10103
Brown-rot decay results in rapid reduction in degree of polymerization (DP) of holocellulose with concomitant strength loss (MOR) without removing lignin. Development of new methods of wood protection will require focusing on early events in the sequence of depolymerization. Bordered pit membranes (sapwood) represent a readily available source of non-lignified carbohydrate, ie. pectin and cellulos...
F Green III, J L Tschernitz, T A Kuster, T L Highley
Antagonistic properties of Gliocladium virens against wood attacking fungi
1996 - IRG/WP 96-10162
Gliocladium virens has shown good antagonism against decay fungi in agar medium and in wood blocks. Gliotoxin produced by Gliocladium virens is associated with biocontrol of some plant diseases, but its importance to biocontrol of wood-attacking fungi is unknown. We investigated the ability of gliotoxin-producing (GLT+) isolates of Gliocladium virens and gliotoxin-deficient (GLT-) mutants of Glioc...
T L Highley, H S Ananthapadmanabha, C R Howell
Micromorphology of oak wood degraded by brown rot fungus Coniophora puteana
2000 - IRG/WP 00-10356
To characterize the degradation of hardwood by brown rot fungus, Coniophora puteana was incubated on the wood blocks of Quercus accutissima. For comparison, the same fungus was also incubated on the pine wood blocks of Pinus densiflora. In softwood, the shape of the wood cells and thickness of the cell appeared unchanged even the loss of birefringence in the affected areas. In contrast, oak wood d...
Yoon Soo Kim, Seung-Gon Wi, Kwang-Ho Lee
Screening of bacteria, yeasts and Trichoderma isolates for antagonism toward stain and mould fungi on agar media and wood
1999 - IRG/WP 99-20159
A screening programme of soil bacteria for antagonism toward mould and wood stain fungi was undertaken on 8 types of agar-based media by application of several bacteria to each plate. The rapid screening method was subsequently verified by testing antagonism of the most promising bacteria on Scots pine sapwood. Most of the 64 bacterial showed antagonistic effects on certain media against individua...
C Payne, A Bruce
The importance of blue stain attack for the colonization by wood-rotting fungi of wood not in contact with the ground
1988 - IRG/WP 1349
When used in constructions not in contact with the ground, wood has been shown often to proceed from blue stain to moulds. The appearance of wood rotting fungi is normally delayed. Solid wood artificially inoculated with the blue stain fungus Pullularia pullulans was shown to permit germination of Pycnoporus cinnabarinus basidiospores. This was demonstrated by the use of an indirect and a direct b...
J Bjurman
Evaluation of white-rot fungal growth on Southern Yellow pine wood chips pretreated with blue-stain fungi
2000 - IRG/WP 00-10349
White-rotting basidiomycetes do not colonize on southern yellow pine. This study seeks to reduce the resinous extractive content of southern yellow pine by treating it with blue stain fungi. The mycelial growth of wood-inhabiting ligninolytic white-rot fungi can be achieved on pretreated southern yellow pine wood. Aureobasidium, Ceratocystis, and Ophiostoma spp. removed 70% to 100% of the extracti...
S C Croan
An appraisal of anti-sapstain chemicals in Queensland, Australia
1985 - IRG/WP 3331
Eleven formulations were tested in the field for effectiveness against sapstain, mould and fungi on Pinus elliottii in Queensland. The commercially used sodium pentachlorophenoxide (0.5% a.i.) and Captafol (0.2% a.i.) performed well. Busan 1009 (0.3% a.i.), Protek T (5.0% a.i.), Woodgard E.S. and E.C. (0.8% a.i.), together with sodium tetrachlorophenoxide (0.5% a.i.) offer potential as anti-sapsta...
L E Leightley
Blue stain in timber in service. Preliminary results of the IRG collaborative tests to compare natural and artificial weathering
1978 - IRG/WP 286
The collaborative programme was initiated at IRG Meetings in Wildhaus, 1976. The six collaborators were BAM (Berlin), Cuprinol Ltd (UK), EMPA (Switzerland), GORI (Denmark), PRL (UK) and Imperial College (UK). Experimental plans were finalised in December 1976 and panels treated by Cuprinol Ltd early in 1977. Natural weathering was carried out by BAM, Cuprinol, EMPA, GORI and PRL during April-Septe...
A F Bravery, D J Dickinson
The development of blue stain in service in sapwood of European softwood species
1997 - IRG/WP 97-10236
The utilisation of softwood species for window joinery applications is gaining importance in countries frequently using tropical hardwood species up to now. Since wood preservation is not always part of the total concept of window frames manufactured from sapwood containing wood elements it is essential to know the impact of durability on the performance. Moisture content control is a major tool i...
J Van Acker, R Klaassen, H Militz, M Stevens
Comparison of three methods of quantitative evaluation of sapstain in rubberwood
2000 - IRG/WP 00-20188
Assessing the extent of fungal stain on wood during laboratory trials is a subjective process and is subjected to considerable variation between individual evaluators and specimen. The purpose of this paper was to explore the potential of three quantitative methods of wood surface measurement of rubberwood specimens degraded by sapstain and mould fungui (Botrydiplodia theobromae, Aureobasidium pul...
A J Ashari, J W Palfreyman, A H H Wong
The role of chitinase in bioprotectant activity against staining fungi
1996 - IRG/WP 96-10175
Chitin is an important structural component of the hyphae of many wood staining fungi and its disruption can lead to dramatic declines in their growth. A number of bioprotectants have been shown to produce chitinases in liquid cultures, but the role of these enzymes in bioprotection remains poorly understood. The levels of these enzymes was studied by inoculating ponderosa pine sapwood wafers with...
J Liu, J J Morrell
Field evaluation of alternative antisapstain chemicals
1982 - IRG/WP 3198
Seven alternative antisapstain formulations containing four different active ingredients were field tested during the summer and fall of 1981. The test was designed to evaluate the potential long term effectiveness of PQ-8 (Chapman Chemical Co.) containing copper-8-quinolinolate, Busan 30 (Buckman Laboratories) containing 2-(thiocyanomethylthio)benzothiazole, BL2398 (Buckman Laboratories) containi...
D V Plackett
Oxalic acid metabolism of Postia placenta
1992 - IRG/WP 92-1566
The oxalic acid metabolism of Postia placenta was studied in liquid culture in order to identify the metabolic pathways of biosynthesis and to determine whether oxalic acid physiology could be correlated with efficiency in wood decay. Oxalic acid production was determined for test strain MAD698 grown in a basal defined medium with a variety of different carbohydrate and nitrogen sources. The highe...
J A Micales
Immuno-scanning electron microscopic localization of extracellular polysaccharidases within the fibrillar sheath of the brown rot fungus Postia placenta
1991 - IRG/WP 1497
Extracellular polysaccharidases of the brown-rot fungus Postia placenta were localized using colloidal gold labeled monoclonal antibodies to the B-1,4-xylanase (32-36kDa) fraction of Postia placenta. Postia placenta was grown from agar onto glass coverslips, immunolabeled with or without prior fixation, and examined by SEM. Enzymes were localized on the hyphal surface and on the clumped fibrillar ...
F Green III, C A Clausen, M J Larsen, T L Highley
The effect of Tween 80 on the growth, morphology, and enzyme secretion of Postia placenta
1990 - IRG/WP 1456
The nonionic surfactant Tween 80 (polyethylene oxide sorbitan mono-oleate) has been reported to increase enzyme production and/or secretion in bacteria and fungi. Such a procedure could greatly facilitate research into the physiology of wood-decay fungi since quantities of available enzyme are often limiting. The brown-rot fungus Postia placenta was grown in a synthetic medium supplemented with 0,...
J A Micales
Changes in some important mechanical and physical properties of untreated and treated mining timber after exposure to the conditions of a colliery
1996 - IRG/WP 96-20082
Each of salt treated and untreated mining timber (wedge) pairs with 5x15 cm² cross-section and 155 cm length prepared from Scots pine, Bornmüller's fir and oriental beech was cut in the small standard test specimens to determine changes in some important mechanical and physical properties, 13 month after exposure to the conditions of Kozlu Hard Coal Mines in the depth of 52 m. Thus, the...
A Bobat
Growth inhibitory effects on blue-stain fungi of applied electricity fields
1996 - IRG/WP 96-10167
Exploratory laboratory experiments on the effects of electricity on two blue stain fungi Aureobasidium pullulans and Ceratocystis piceae on wood revealed that a potential gradient of 1 V/cm corresponding to a current of 15 mA (DC), applied without interruption during a 2 week experimental period, leads to an inhibition of the growth of these fungi. Germination is somewhat more sensitive than mycel...
J Bjurman
Testing blue stain fungicides for joinery timber in combination with natural weathering
1976 - IRG/WP 268
Joinery timber in outside use becomes affected by blue-stain after a short time of exposure. This is especially the case with pine sapwood treated with unpigmented lacquer, but also with other timber species as well as different types of surface treatment. According to the basic investigations of BUTIN this is due to special types of blue-stain fungi, called "Lack-bläue" (lacquer blue-stain), in ...
H Willeitner
Preliminary investigation on the natural durability of Guayule (Parthenium argentatum)-based wood products
2000 - IRG/WP 00-40154
Conventional preservatives used to protect wood from insect and microbial damages are presently of major concern to human health and the environment. Finding alternative and economical preservatives has not been successful. Previous studies have shown that the resinous material extracted from the guayule plant (Parthenium argentatum, Gray) has both insect- and microbial-resistant properties. Unfor...
F S Nakayama, P Chow, D S Bajwa, J A Youngquist, J H Muehl, A M Krzysik
Effect of remediation on the release of copper, chromium, and arsenic from particleboard made from CCA treated wood
2001 - IRG/WP 01-50170
This study sought to determine the effect of remediation with oxalic acid (OA) extraction and Bacillus licheniformis fermentation on the release of copper, chromium, and arsenic from particleboard made from remediated wood particles and also investigates durability of the particleboard against white and brown- rot fungi. Particleboard samples were manufactured using untreated, CCA-treated, OA-extr...
S N Kartal, C A Clausen
Fumigation of red beech in New Zealand for prevention of graystain
2000 - IRG/WP 00-10343
The discoloration of sapwood of red beech (Nothofagus fusca) after drying has been an ongoing problem which may lower value of material for certain applications (such as flooring) by as much as 50%. The dark gray stain noted after the drying and planing of lumber is not prevented by fungicide dips, and is most likely similar to the enzyme-mediated stain noted in a variety of commercial hardwoods. ...
E L Schmidt, B Kreber
Development of bluestain in commercially harvested logs in Britain
1996 - IRG/WP 96-10150
In Britain, mechanised harvesting of conifer forestry crops is now the preferred method of felling where terrain and access allows. However, use of mechanised harvesters can lead to excessive debarking, loosening of the bark and wood splintering with, on average, about a third of the bark removed from the more severely damaged logs. More bark has also been observed to be lost from logs harvested e...
A Uzunovic, J F Webber, D J Dickinson