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Design, synthesis, characterisation and effectiveness of ‘Locked-in-Boron’ chemicals for H3.2 level of wood protection
2011 - IRG/WP 11-30577
Boratrane molecules with five-membered and six-membered molecular ring systems, and with various ring substituents were synthesised, characterised and formulated for wood treatment for accelerated laboratory bioassays using wood decay fungi as test organisms. Six-membered ring boratranes showed lower efficacy in laboratory assays than five-membered ring boratranes. One alkyl-substituted boratrane with a five-membered ring molecular structure was used in a 10-year natural hazard exposure test using lap-joint specimens treated with three boratrane concentrations. The half-life for boric acid controlled release for wood treated with the boratrane at a nominal 0.1% boric acid equivalent (bae) was approximately 4 years, while that for a nominal 1% bae was approximately 7 years, compared with a half-life of 10 months for conventional boric acid/borate wood treatment.
R Franich, H Kroese, S Gallagher, S Hill, B Kelly, G Billett, R Meder, W Rae

What can DNA fingerprinting, aggression tests and morphometry contribute to the identification of colonies of the Formosan subterranean termite
2000 - IRG/WP 00-10371
Multilocus DNA fingerprinting, aggression tests and morphometry were compared to evaluate their potential for the identification of colonies of the Formosan subterranean termite, Coptotermes formosanus (Isoptera: Rhinotermitidae) in Hawaii. DNA fingerprinting separates the termites from all studied collection sites. Since the genetic similarity between termites from different collection sites lies in the range of the genetic background similarity in the population, collection sites in this study represent independent colonies. No significant differences could be found in the intra- and intercolonial aggression levels. While aggression tests do not support colony identification, morphometric measurements do show differentiations between colonies. However, classification of individuals to their original colony does not reach the 100% success provided by genetic analyses. No correlation between genetic similarities and aggression levels or morphometric distances could be found. This suggests that neither aggression levels nor morphometric parameters are significantly influenced by genetic factors in this species. Genetic studies appear to be the most useful approach to the identification of colonies and the analysis of small scale population structures in C. formosanus.
C Husseneder, J K Grace

The effect of certain wood extractives on the growth of marine micro-organisms
1977 - IRG/WP 438
S E J Furtado, E B G Jones, J D Bultman

The restricted distribution of Serpula lacrymans in Australian buildings
1989 - IRG/WP 1382
Temperature data has been gathered over a number of years, not only for flooring regions of various buildings in Melbourne, but also within roof spaces and external to the buildings. Findings are discussed in relation to the distribution of Serpula lacrymans within Australia, its restriction to certain types of building construction and its restriction to flooring regions. The subfloor spaces of badly-ventilated, masonry buildings are highlighted as being better suited than are the subfloor spaces of, for example, Japanese buildings for the activity of this fungus. Hence Serpula lacrymans is very restricted in its distribution in Australia, yet where it is active it does grow rapidly and causes rapid flooring failures.
J D Thornton

Basidiosporogenesis by the white-rot basidiomycetes in vitr
1994 - IRG/WP 94-10081
Basidiospores of all forest-inhabiting basidiomycetes are a primary source of infection causing wood decay. However, most studies evaluating wood preservatives have used mycelia or basidiospores obtained from wild mushrooms. The objective of this study was to demonstrate in vitro methods that promote carpogenesis and basidiosporogenesis by the white-rot basidiomycetes, Schizophyllum commune and Trametes versicolor. After preincubation in the dark at 27°C for three to fifteen days, basidiospores were produced in four to sixteen weeks in basidiomes exposed to light at 12°C. Adequate light exposure, aeration, and low temperature treatment after preincubation are essential for fruiting body of these white-rotting basidiomycetes. Carpogenesis and basidiosporogenesis of Schizophyllum commune is controlled by nitrogen and carbon limitation. However, fruiting body formation in Trametes versicolor was induced by nitrogen limitation. Walset cellulose was found to be the best carboun source for carpogenesis and subsequent basidiosporogenesis. These results demonstrate the feasibility of using various potential inhibitors on basidiospore germination rather than relying on mycelial growth.
S C Croan

European standardization for wood preservation
1989 - IRG/WP 2335
G Castan

Molecular Microbiology and Wood Protection
2009 - IRG/WP 09-20416
During the last decade, the development of molecular tools has allowed significant advances in environmental microbiology. Such techniques have proved to be invaluable tools for the qualitative and quantitative description of environmental microbial communities. The aim of this paper, written for non-specialized readers, is to discuss the possible applications of such tools in wood preservation field, focusing particularly on the improvement of wood durability tests.
E Gelhaye, M Morel

Molecular studies on isolates of Serpula lacrymans
1989 - IRG/WP 1421
The major protein species present in detergent extracts of 14 different Serpula lacrymans isolates have been compared, by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), with a standard strain, viz. Serpula lacrymans FPRL 12C. Following silver staining of SDS gels the major protein species identified in 12 isolates were similar to those found in the standard strain. However differences were found when the final two isolates were compared with FPRL 12C, both isolates had extra molecular species not present in 12C and both were lacking some present in the standard strain. Comparison of the protein species identified in Serpula lacrymans isolates with those identified in extracts of other fungal organisms, viz. brown and white rot causing basidiomycetes and non-basidiomycetes indicated that the Serpula isolates were more similar to each other than to other organisms. Some molecular differences could be identified when individual isolates were cultured on different media, i.e. liquid culture or agar, only minor differences were seen when individual isolates were subcultured. These results indicate that whilst care must be taken to ensure as near identical conditions as possible for culture of organisms if their molecular species are to be compared by SDS-PAGE and silver staining, consistent results can be obtained using this technique. The technique may therefore offer a method of distinguishing between isolates, strains and species of wood decay basidiomycetes, and identifying new isolates.
A Vigrow, D Button, J W Palfreyman, B King, B M Hegarty

Effect of methylene bisthiocyanate on morphology and ultra-structure of a sapstain fungus, Ophiostoma floccosum
2003 - IRG/WP 03-10471
In vitro effects of methylene bisthiocyanate (MBT) on hyphal morphology and ultrastructure of Ophiostoma floccosum were examined using differential interference contrast, epifluorescence and transmission electron microscopy (TEM). Differential interference contrast microscopy suggested that MBT caused rapid changes to the morphology of O. floccosum resulting in excessive formation of vacuoles and granules within the cytoplasm. Epifluorescence microscopy indicated that damage to the plasma membrane occurred in the MBT treated, but not the control, hyphae. TEM showed that in MBT treated hyphae, the plasma membrane had retracted from the cell wall. Cytoplasmic aggregation and increased vacuolation were also observed. Furthermore, complete disintegration of the cytoplasmic organelles was seen in more advanced stages of MBT induced damage. In contrast, plasma membrane of untreated hyphae closely adhered to the cell wall showing cytoplasma with typical cell organelles. Based on the results from this study we suggest that the primary site of mode of action of MBT occurred at the plasma membrane, which then triggered subsequent changes within the cytoplasm of the test fungus.
T Singh, B Kreber, R N Wakeling, A Stewart

Termiticidal chemicals derived from tropical tree resins
1991 - IRG/WP 1477
To test the hypothesis that defensive chemicals protect tropical primary forest trees against biological attack, a bioassay and fractionation program was conducted in Indonesia. Fresh dipterocarp resins were fed in no-choice tests to Neotermes dalbergiae termites on 4.5 cm filter papers, or tested for inhibition of fungal growth. Fractionation of biologically active resins via flash column chromatography, followed by subsequent bioassay and analytical chemical studies, revealed that several sesquiterpene compounds inhibited fungal growth and killed 50% of test termites in 3-7 days. Toxic fractions contained caryophyllene, caryophyllene oxide, alloaromadendrene, and other compounds. From the relatively non-toxic a-gurjunene, novel termiticidal compounds were synthesized, indicating the potential for manufacture of insecticides from natural products.
A Messer, K McCormick, D Richardson, Sunjaya, H Hagedorn, J Meinwald

Sex pheromone of the male house longhorn beetle Hylotrupes bajulus (L.) (Coleoptera: Cerambycidae)
1995 - IRG/WP 95-10100
Since 1990 studies have been conducted with respect to the chemical communication of the house longhorn beetle Hylotrupes bajulus (L.) (Coleoptera: Cerambycidae). The structure of glands located in the prothorax of the beetles was examined with light and scanning electron microscopy. The analyses of different extracts from beetles resulted in the finding and identification (GC-, GC/MS-, and HR-GC/MS-studies) of specific substances derived from the prothoracal glands: (3R)-3-hydroxy-2-hexanone, (2R,3S)-2,3-hexanediol and (2R,3R)-2,3hexanediol. In wind tunnel experiments, unmated female beetles were attracted over a distance of 1m by males, headspace extracts of males, the 3 major components of the glands as well as by the synthetic blends of the components. Thus, the bioassays revealed the initiation of premating behaviour by emission of a long-range sex pheromone from the male prothoracal glands. The pheromone functions as activator, attractant and possibly aphrodisiac for unmated females. Further studies are conducted with respect to disturbance and prevention of mating behaviour of Hylotrupes bajulus in the attics of houses by using pheromone traps.
U Noldt, R Fettköther, F Schröder, H Meyer, K Dettner, W Francke, W A König

Basidiosporogenesis by brown-rot basidiomycetes in vitro
1995 - IRG/WP 95-10126
Basidiospores of wood-rotting basidiomycetes are a primary sourse of infection causing wood biodeterioration, especially in wood above ground. Most studies evaluating wood preservatives have used mycelia or basidiospores obtained from wild mushrooms. The objective of this study was to demonstrate in vitro methods that promote carpogenesis and basidiosporogenesis by the brown-rot fungi Antrodia carbonisa, Neolentinus lepideus, and Postia placenta. After preincubation in the dark at 27°C for 3 to 11 days, basidiospores were easily prodused in 1 to 4 months by basidiomata exposed to light at 12°C. Adequate light exposure, aeration, and low temperature treatment after preincubation are essential for fruiting body formation of these brown-rot basidiomycetes. The morphology of the basidiomata differed according to the basidiomycetes and the medium used. These results demonstrate that an enormous quantity of basidiosporee can be easily and continuously prodused in 2 to 4 months in vitro.
S C Croan

Growth of two selected sapstain fungi and one mould on chitosan amended nutrient medium
2003 - IRG/WP 03-10466
In vitro studies were undertaken to investigate the effect of chitosan on growth of Leptographium procerum, Sphaeropsis sapinea and Trichoderma harzianum. Chitosan was tested at three molecular weight (MW) ranges and different concentrations formulated as either a powdered suspension or as a solution. The results generally showed that low MW chitosan produced a greater inhibitory effect on growth of test fungi than medium and high MW, irrespective of the chitosan formulation used. However, chitosan was more effective when applied in solution with much lower concentrations exerting inhibition of test fungi than chitosan suspensions. Furthermore, susceptibility of test fungi to chitosan differed, with T. harzianum being the most tolerant and S. sapinea the most sensitive species irrespective of chitosan formulation used.
C Chittenden, R N Wakeling, B Kreber

Fungal degradation of wood treated with metal-based preservatives. Part 2: Redox states of chromium
1996 - IRG/WP 96-10164
Concerns have arisen about the leaching of heavy metals from wood treated with metal-based preservatives, such as chromated copper arsenate (CCA). Of particular concern is the toxic redox state of chromium and arsenic in aging and decayed CCA-treated wood. Generally, hexavalent chromium is more toxic than trivalent chromium and trivalent arsenic is more toxic than pentavalent arsenic. The desired outcome from treating wood with CCA is total change of Cr(VI) to Cr(III) and As(III) to As(V). As part of an on-going study to determine the fate of copper, chromium and arsenic during aging and decay of CCA-treated wood, we detected Cr(III) and Cr(VI) in situ in CCA-treated southern yellow pine lumber. The redox states of Cr were determined using synchrotron X-ray fluorescence spectroscopy (SXRF). An SXRF microprobe was used to to detect Cr redox states by measuring X-ray absorption near-edge structure (XANES). The ratio of Cr(III) to Cr(VI) was determined (1) on the surface and interior of lumber two years after CCA treatment and (2) in lumber during decay by a CCA-tolerant fungus, Meruliporia incrassata TFFH-294. The XANES spectrum for Cr(VI) has a strong pre-edge feature that is not present in the spectrum for Cr(III). Only the Cr(III) XANES spectrum was detected on the surface and in the interior of the wood, indicating total reduction of Cr(VI). The XANES spectrum for Cr(III) was detected in wood after 12 week decay by Meruliporia incrassata TFFH-294, indicating that the fungus does not oxidize Cr(III) to Cr(VI) during the decay process. We are currently using XANES spectroscopy to detect and map in situ redox states of As in CCA-treated wood.
B Illman, S Bajt, T L Highley

The permanence of permethrin in wood preservation
1984 - IRG/WP 3288
The permanence of the synthetic pyrethroid permethrin in treated wood has been assessed for double vacuum and immersion treated Scots pine sapwood and whitewood using a 0.5% m/m solution of the insecticide in a hydrocarbon solvent. It is concluded that for all but the outermost 0.5 mm of the treated battens the distribution of the permethrin is relatively permanent. The outermost 0.5 mm appears vulnerable to degradation rather than volatile loss, and this varies with timber species and the loading in that zone. Linking this information with published bioassay work allows speculation as to the strength of treating solutions needed for adequate long-term protection
R J Orsler, M W S Stone

Isolation of the dry rot fungus, Serpula lacrymans, from the forests of the Himalayan Foothills
1995 - IRG/WP 95-10129
Previous expeditions to the Himalayas (Singh 1993, 1994) have reported on the presence in this area of the dry rot fungus Serpula lacrymans. However, attempts to isolate the organism from material brought back from these expeditions were not successful. In this paper we report on the isolation of Serpula lacrymans from spores and cord material brought back from the Narkanda region of the Himalayas. Whilst morphological analysis suggested the nature of the material as being Serpula lacrymans confirmation of this has been via protein fingerprint studies using SDS-PAGE. In this paper the natural habitat of the dry rot fungus will be discussed and compared with the building environment in which the organism grows in Europe, Japan, etc. In addition information on a range of other assowiated fungal species, also isolated from the Himalayan forest, will be given.
N A White, J W Palfreyman, J Singh, S Singh

The effect of low molecular weight chelators on iron chelation and free radical generation as studied by ESR measurement
2000 - IRG/WP 00-10367
The focus of this work was to improve our current knowledge of the non-enzymatic mechanisms involved in brown-rot decay. Electron Spin Resonance (ESR), also known as Electron Paramagnetic Resonance (EPR), is an attractive technique for the identification and study of chemical species containing unpaired electrons (such as radicals and certain transition metal species). ESR spin-trapping techniques are also commonly used to study very reactive and short-lived free radical species. It has been proposed that low MW chelators as well as Fenton reagents are involved in wood brown-rot decay, at least in early non-enzymatic stages. In this work, the binding between a chelator model compound and ferric iron was studied by ESR spectroscopy. The effects of the chelator model compound, Fenton reagents, as well as the reaction conditions on free radical generation were also studied using ESR spin-trapping techniques. The results indicate: 1. The relative amount of ferric iron bound to chelators is directly related to the chelator / iron ratio in the system. The relative quantity of the chelator-iron complex can be determined by measuring the intensities of the characteristic g4.3 ESR signal. 2. The effects of the chelator/iron ratio, the pH, and other reaction parameters on the hydroxyl radical generation in a Fenton type system could be determined using ESR spin-trapping techniques. 3. Data support the hypothesis that superoxide radicals are involved in the chelator mediated Fenton processes.
Yuhui Qian, B Goodell

Laboratory evaluation of organophosphates as termiticides
1985 - IRG/WP 3330
In accordance with Japan Wood Preserving Association Standard 11(1) laboratory evaluations of five organophosphate insecticides and chlordane were conducted. Superficially treated sapwood of Pinus densiflora Sieb. et Zucc. (10 x 10 x 20 mm³) was compulsorily exposed to the attacks of 150 workers and 15 soldiers of Coptotermes formosanus Shiraki for 21 days at 28±2°C in the dark. Percentage weight loss of the wood blocks was determined at the end of the test. Termite mortality was additionally calculated at regular intervals. Of five organophosphate insecticides evaluated, chlorpyrifos and phoxim were the most effective and were followed by acephate and tetrachlorvinphos. Required treating concentrations were < 0.1% for chlorpyrifos, phoxim and tetrachlorovinphos, 0.1-0.2% for acephate and 0.2-0.4% for fenitrothion. For chlordane 0.5-1.0% was desired. Results based on the percentage weight loss indicated that organophosphates were generally more effective than chlordane in controlling termites. It is, therefore, worthy to take up potential chemicals for further investigation.
K Tsunoda, K Nishimoto

The use of TCMTB in applications other than sapstain prevention: A review
1990 - IRG/WP 3606
The efficacy of TCMTB against staining fungi and surface moulds has been thoroughly investigated during the last decade. As a result, the chemical is used as an alternative to the chlorinated phenols in various parts of the world for the preservation of freshly sawn timber. Less known are the data obtained against brown rot, white rot and soft rot fungi. The termite repellent and bactericidal properties of the chemical widen the scope of application possibilities. The objective of this article is to report on the data actually available.
R Van der Eynde

A novel defaunation method of the protozoa to investigate cellulose metabolism in Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae)
1994 - IRG/WP 94-10050
The largest protozoa in the hindgut of workers of Formosan subterranean termite, Coptotermes formosanus Shiraki, was selectively eliminated by forced-feeding on low-molecular weight cellulose (LC) with a mean DP of 17. Although one week&apos;s feeding on LC caused perfect disappearance of Pseudotrichonympha grassii Koidzumi, the selective defaunation method itself had no detrimental effect on the health conditions of termite on the basis of survival rates and weight changes of workers in the latter feeding. In addition, the fact that the defaunated workers repidly recovered their wood-attacking activity by being mixed with normally faunated workers could well support this assumption. By the results of changes of protozoan fauna when selectively defaunated workers were forced to feed on various cellulose substrates, it was suggested that each protozoan species had its inherent role in cellulose metabolism.
T Yoshimura, K Tsunoda, M Takahashi

Role of cell wall structure in soft rot decay of bamboo
1995 - IRG/WP 95-10133
Models of soft rot hyphal penetration of bamboo cell walls are proposed. Soft rot hyphae show an interesting capability of penetrating the bamboo cell wall in different forms; typical longitudinal penetrating hyphae and tangentially orientated penetrating hyphae. The second form of penetration was found to be different from that normally associated with wood cell walls. The differences can be attributed to the cell wall structure of bamboo. Soft rot hyphae normally follow the microfibrillar orientation in either the broad lamellae or the narrow lamellae in bamboo cell walls. Hyphae that grow in the broad lamellae normally penetrate in the longitudinal direction and follow the orientation of the microfibrils of this layer of the cell wall. This produces a &apos;typical&apos; longitudinal penetrating hyphae and cavity. Soft rot hyphae are also found penetrating in the tangential direction. These arise from radially orientated hyphae trying to penetrate across the lamellated cell wall neighbouring cells. When a radially orientated hyphae encounters the narrow lamellae, the hyphae can reorientate in the direction of the microfibrils in this lamellae. Thus, the hyphae penetrate in a tangential direction in the cell wall. These types of penetrations are not seen in wood cell walls.
O Sulaiman, R J Murphy

Work programme of CEN/TC 38 (April 1999) and European publications
1999 - IRG/WP 99-20165
Scope of the CEN/TC38: Standardization of the characteristics of natural or conferred durability of wood and its derived materials against biological agents, including the characteristics of protection products and associated processes to obtain this durability. This applies in particular to: - the identification of hazard classes-, - the test methods (wood preservatives and treated wood and wood based materials) and interpretation of the results; - the specification of wood preservatives and treated wood by classes of hazard including processes-, - quality control methods-, -terminology.
R Hüe

The dry rot fungus Serpula lacrymans, its growth and damaging of wood
2004 - IRG/WP 04-10511
The dry rot fungus (Serpula lacrymans) is one of the most dangerous wood rotting fungi, especially in the built environment. In our mycological laboratory more experiments with this fungus have been carried out aimed at:- its growth under stable and variable climatic conditions, - its possibility to attack either natural wood of different species and also modified wood primary pre-treated with some other fungi, aggressive chemicals and high temperatures, - its influence on the molecular and anatomical wood structure, - its influence on the acoustical, electric, strength and some other properties of decayed wood which can be applied for its identification.
L Reinprecht

Preliminary study on relation of wood structure to copper/chrome/arsenic (CCA) distribution in kempas (Koompassia malaccensis)
1995 - IRG/WP 95-40054
Kempas had been treated with copper/chrome/arsenic (CCA) preservative using full cell process. Analysis of preservative distribution at the micro level in relation to wood structure was carried out using scanning electron microscope (SEM) and energy dispersive X-ray (EDXA) analysis. The results showed that CCA elements were detected in all wood tissues at different ratios. Distribution of chemical elements appeared to be much greater in the tangential longitudinal section (TLS) than the transverse section (TS). Though the amount of chemical elements had not been quantified from the radial longitudinal section (RLS), the SEM observations showed a high distribution of chemical precipitate. In all the wood tissues observed, Cr appeared in highest amount. The precipitate analysed by EDXA, showed As in greater amount than Cr or Cu. Silica content was highest in fibres and rays as determined by EDXA but could not be detected in structural form under SEM or light microscope.
S Ani, S Salamah

Evaluation of chlorpyrifos as an insecticidal component of a wood preservative
1984 - IRG/WP 3301
After two years of laboratory and field testing, chlorpyrifos is showing excellent potential as an insecticidal treatment to wood. In laboratory termite tests, retentions as low as 1-2 parts-per-million or approximately 0.0008 kg/m³ (0.00005 lbs/ft³) are effective against the Coptotermes formosanus. Laboratory leaching tests have shown no significant effect on the concentration of the retained chlorpyrifos. Pressure treatments and dip treatments, as an aqueous emulsion or oil solution, have resulted in good penetration of effective concentrations. Combinations of chlorpyrifos and various fungicides are being evaluated.
K Rose, J Kozuma, P Sparrow

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