Your search resulted in 3832 documents. Displaying 25 entries per page.
Fungal siderophores and their rôle in wood biodegradation
1990 - IRG/WP 1442
Iron and other metals such as manganese, play an important role in the metabolic functions of fungi that cause wood deterioration. These transition metals are also found in, or associated with, the extracellular fungal enzymes shown to be directly involved in the decay process. Recently our research group was able to show that siderophores (low molecular weight biological chelators) are produced b...
J Jellison, B Goodell, F Fekete, V Chandhoke
Microbial decay in an extremely durable Malaysian hardwood Belian (Eusideroxylon zwageri) - an overview
1997 - IRG/WP 97-10216
The heartwood of Belian (Eusideroxylon zwageri) is highly regarded among the naturally durable Malaysian hardwoods, and is therefore a choice timber for soilcontact use in the humid tropics such as untreated telecommunication poles, fence posts and railway sleepers. The high microbial resistance of the wood is evidenced by the mere superficial degradation observed in some pole samples after 20 yea...
A H H Wong, A P Singh
Synergistic combination of an antioxidant and wood preservative: a preliminary study
1998 - IRG/WP 98-30172
We previously proposed that extractives in highly durable angiosperm heartwood may protect wood against white-rot fungal colonization and subsequent degradation by a dual mechanism: extractives have some fungicidal activity and are also free radical scavengers (antioxidants) and thus interfere with the fungal free radical degradative mechanisms. We tested this hypothesis using the commercial bioci...
T Schultz, D D Nicholas, J Minn, K D McMurtrey, T H Fisher
Window test. Direct testing of wood resistance to decay: A study of its fitness, its reliability and its accelerating factor
1984 - IRG/WP 2219
This is the results of an experiment using the window-test specimens, exposing the specimens to three different types of testing procedure: 1. Natural infestation in the open air; 2. Artificial infestation and exposure in the open air; 3. Artificial infestation in a green-house. The results show good similiraties of the three parallel tests in term of decay, and assess the reliability of the windo...
G R Y Déon, L N Trong
Nasutitermes exitiosus and wood-rotting fungi in Eucalyptus regnans, E. acmenioides, E. wandoo, and E. marginata: force-feeding, laboratory study
1985 - IRG/WP 1231
Under a force-feeding regime, the termitid Nasutitermes exitiosus was fed on four eucalypt timbers infested with several fungal species to investigate the influence of such fungus-infested timbers on mass of wood lost, termite biomass, fat content and water content. The results showed that wood mass losses were markedly affected by species of fungi and timber. The interaction of fungi and timbers ...
D B A Ruyooka
Wood decay of Pinus sylvestris L. and Fagus sylvatica L. by marine fungi. Part 2
1991 - IRG/WP 1471
The water-logged wood conservation requires a good knowledge of the wood decay organims which produce the degradation. Previous conducted studies (ESCORIAL, TROYA, GARCIA DE LOS RIOS, 1990) have shown that the incubation times normally used for in vitro laboratory tests are not sufficients for a significant wood degradation. This has been the reason why the aim of this work was the study of such d...
M T De Troya, A M Navarrete, M C Escorial
Investigation of extracellular mucilaginous material in some wood decay fungi
1996 - IRG/WP 96-10188
The external morphology of the extracellular mucilagenous material (ECM) produced by Coriolus versicolor and Coniophora puteana during colonization of Scots pine and beech was studies using SEM. Specimens were examined in the frozen hydrated, freeze-dried and critical point dried state. All technics produced artefacts but the ECM was best preserved when examined the frozen hydated state. Critical ...
A R Abu, D J Dickinson, R J Murphy
Targeted inhibition of wood decay fungi: degradation of cotton cellulose
1999 - IRG/WP 99-10321
Brown-rot decay is responsible for 80% of the damage and replacement of wood in service. For nearly thirty years, researchers have postulated a one-electron oxidase system combining Fe+2 oxalic acid, and H2O2 in the production of hydroxy radicals which ultimately oxidize cellulose in situ. Recently, researchers have been investigating antioxicants, in combination with biocides (Schultz, et al.,199...
F Green III, T A Kuster
Effect of moisture and cellulosic substrate on decay of hardwoods by soft-rot fungi
1982 - IRG/WP 2173
The development by Forintek Canada Corp. of standard test procedures for laboratory preservative evaluations using soft-rot fungi was requested by the American Wood Preservers' Association. In Europe, through cooperative studies in the International Research Group on Wood Preservation, several attempts have been made to produce a standard procedure, but variability in results obtained bet...
A Byrne, R S Smith
Effect of crude tall oil, linseed oil and rapeseed oil on the growth of the decay fungi
2002 - IRG/WP 02-30299
The influence of crude tall oil, linseed oil and rapeseed oil on the growth of Coniophora puteana, Poria placenta and Coriolus versicolor was studied. The selected test oils were observed to have different effects on the the fungal growth. Crude tall oil inhibited the radial growth of all fungi. Rapeseed oil either accelerated or inhibited the growth of fungi depending on the type of fungus involv...
L Paajanen, A-C Ritschkoff
Natural Durability studies and Changes in wood chemistry of some Ghanaian hardwoods during decay by white- and brown-rot fungi
2004 - IRG/WP 04-10542
The natural decay resistance of Esa (Celtis mildbraedii), Wawabima (Sterculia rhinopetela) and Dahoma (Piptadeniastrum africanum) obtained from Ghana was determined according to BS EN 113 (1997). Esa was found not durable to the white-rot, but very durable to the brown-rot; Wawabima was very durable to both white- and brown-rots; and Dahoma was durable to the white-rot, and very durable to the bro...
Zeen Huang, K Maher, S A Amartey
The effect of initial moisture content on wood decay at different levels of gaseous oxygen concentration
1999 - IRG/WP 99-10316
The influence of initial moisture content on wood decay at different levels of atmospheric oxygen concentration was studied. Three fungi, Coriolus versicolor a white rot, Coniophora puteana a brown rot, and Chaetomium globosum a soft rot, were chosen. The mycelia of the fungi were inoculated on mini blocks of Fagus sylvatica (beech) and Pinus sylvestris (Scots pine). Incubations were under four le...
S M Kazemi, D J Dickinson, R J Murphy
Screening wood preservatives: Comparison of the soil block, agar block and agar plate tests
1993 - IRG/WP 93-20001
Several test procedures have been developed over the years to screen potential biocides for their value as wood preservatives. Each test has inherent advantages and disadvantages. In this paper the relative merits of the soil block, agar block and agar plate tests are compared. Eight commercially available biocides encompassing inorganic and organic systems were tested against four basidiomycete d...
K J Archer, D D Nicholas, T Schultz
Biological control of wood decay fungi. - Part II. Effects of exogenous nitrogen on effectiveness
2000 - IRG/WP 00-10360
The effects of nitrogen (urea and ammonium nitrate) on the ability of Trichoderma harzianum to inhibit the enzyme capabilities and decay capacities of Trametes versicolor and Gloeophyllum trabeum were investigated using a small wood sandwich decay test. The biocontrol fungus generally had a greater effect on the brown rot fungus, confirming previous reports. Nitrogen produced inconsistent effects ...
E A Canessa, J J Morrell
Eradication of wood decay fungi by means of radio frequency
1998 - IRG/WP 98-10292
High frequency electromagnetic fields i.e. radio frequency (RF) are used in wood industry for heating, gluing and bending of wood and are also appropriate for eradicating of wood decay fungi and insects. We investigated the effects of RF exposure on wood samples which were in vitro infected by Coniophora puteana, Gloeophyllum trabeum and Lentinus lepideus. For each fungus, the lethal temperature a...
F Pohleven, J Resnik, A Kobe
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
Environmentally benign wood preservatives based on organic biocide antioxidant combinations: A brief review of laboratory and field exposure results and discussion of a proposed mechanism
2004 - IRG/WP 04-30335
The combination of various organic biocides with commercial antioxidants generally increased the biocides’ efficacy 2-3 fold against wood-destroying fungi in short-term laboratory decay tests, and some positive results have been obtained after 2-4 years of outdoor exposure. The two antioxidants principally examined, propyl gallate and butylated hydroxytoluene, are low cost and, since both are f...
T Schultz, D D Nicholas, W Henry, C Pittman, D Wipf, B Goodell
Effect of Pseudomonas cepacia on the activity of a mixture of wood staining fungi on ponderosa pine sapwood
1995 - IRG/WP 95-10107
There are major incentives for limiting the degree of fungal discoloration which occurs during wood processing. Most lumber producers apply prophylactic fungicides which limit microbial growth, but increasing restrictions on the use of these chemicals have encouraged the search for alternative stain prevention strategies. Among the possible strategies for stain prevention is biological control. Wh...
J J Morrell, R K Velicheti
EPR observation of Mn(II) in decayed wood
2002 - IRG/WP 02-10443
Preliminary Electron Paramagnetic Resonance (EPR) studies of copper/chromium (CC) treated spruce wood, subjected to laboratory soil decay test showed increased intensities of Mn(II) EPR signal in partially decayed specimens. Several reasons might be responsible for this phenomenon: Mn(II) could originate from the wood after being released from the typical ligand binding, from reduction of other Mn...
M Petric, M Humar, P Kalan, F Pohleven, U Schoknecht, M Šentjurc
Field study: Wood degradation pattern in buildings and utility poles in tropical climates of Nigeria
1992 - IRG/WP 92-1521
The paper is the result of five years field study of wood degradation patterns in three ecological forest zones (Guinea Savannah, Tropical rain forest and mangrove forest zones, respectively). It involved 800 residential buildings and 700 electric overhead transmission poles. The methodology used was a modified Eslyn (6) test. A high rate of Ascomycetes and Basidiomycetes attack especially on the ...
E O Onuorah
Development and Implementation of a DNA – RFLP Database for Wood Decay and Wood Associated Fungi
2004 - IRG/WP 04-10527
We are developing Restriction Fragment Length Polymorphism (RFLP) and Internal Transcribed Spacer (ITS) sequence databases for wood decay basidiomycetes and other fungi associated with wood. These databases currently house information for 39 fungal species consisting of 9 brown-rot basidiomycetes, 12 white rot basidiomycetes, 1 soft rot, 1 stain fungi, and 16 molds or other ascomycetes or imperfe...
S V Diehl, T C McElroy, M L Prewitt
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
Effect of Oil Content on The Performance of Wood Treated with Pentachlorophenol
2003 - IRG/WP 03-30324
This paper details a five-year study on southern pine treated with pentachlorophenol in oil at various oil contents. Results from field stake tests at two Gulf Coast test sites are presented. Both biological efficacy and preservative depletion data are discussed. Results suggest that increasing oil content leads to better performance of wood treated with pentachlorophenol. Test results indicat...
H M Barnes, T L Amburgey, M G Sanders
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
Influence of the decay of spruce chips by the selected fungi on their chemical structure and the pulp properties
2004 - IRG/WP 04-10510
The paper focuses on changes in the weight and in the molecular structure of spruce chips submitted to long-term storing as well as to medium- and long-term model rotting degradation caused by some chosen fungi identified at storing processes on the pile. For the model decay of chips under laboratory conditions during 3 or 6 weeks the white-rot fungi: Phanerochaete chrysosporium, Heterobasidion an...
R Solár, L Reinprecht, A Geffert, F Kacík