Your search resulted in 175 documents. Displaying 25 entries per page.
Blue stain in service on wood surface coatings. Part 3: The nutritional capability of Aureobasidium pullulans compared to other fungi commonly isolated from wood surface coatings
1993 - IRG/WP 93-10035
The nutritional capability of Aureobasidium pullulans was previously examined, using agar plate tests, with regard to nutrient sources that are potentially available in fresh and weathered wood (Sharpe and Dickinson, 1992). This study compared these findings with the nutritional capability of four other fungi (Alternaria sp., Cladosporium cladosporoides, Stemphylium sp. and Trichoderma sp.) commonly isolated from wood surfaee coatings. The liquid culture techniques were used to assess the relative abilities of the fungi to utilise a range of simple sugars, wood sugar alcohols, hemicelluloses, cellulose and lignin degradation compounds. The observations were used to explain why Aureobasidium pullulans is able to occupy so successfully, often in monoculture, the wood-paint interface niche.
P R Sharpe, D J Dickinson
Report on the activities of the European Standardization Committee CEN/TC 38 'Methods of Testing wood preservatives'
1980 - IRG/WP 279 E
Tebuconazole, a new wood-preserving fungicide
1990 - IRG/WP 3634
TEBUCONAZOLE, an anti-fungal triazole compound, has been tested to assess the effectivness as wood preserving fungicide. Tests were made with the active ingredient and also in formulations against basidiomycetes, blue-staining fungi and mould. Results of the DESOWAG laboratories and also from official institutes will be presented. In addition to this there were made different toxicological and ecotoxicological trials according to OECD and EPA guidelines
B Wüstenhöfer, H-W Wegen, W Metzner
Blue stain in service on wood surface coatings. Part 2: The ability of Aureobasidium pullulans to penetrate wood surface coatings
1992 - IRG/WP 92-1557
The ability of Aureobasidium pullulans to penetrate seven different wood surface coatings was examined. Eight isolates of Aureobasidium pullulans were used. Following penetration, light microscopy was used to examine the effect of the fungus upon the coating, and growth at the wood-film interface. The fungus showed different growth capabilities with different types of surface coatings. Some isolates were able to penetrate alkyd based coatings, but were unable to grow in the film. In contrast, after penetration through latex based coatings several isolates were able to produce growth in the films themselves.
P R Sharpe, D J Dickinson
Blue-stain fungi (Ceratocystis spp.) found in Spain on pine woods
1989 - IRG/WP 1410
So far, there is only a very limited reported description of the different Ceratocystis spp. present on fresh wood in Spain. So, the main goal of this work has been the identification of species of this genus causing blue-stain on Pinus pinaster A. Ait. and Pinus sylvestris L. woods. We have also investigated the relationship between the species found and their propagation vectors (insects and wind). Finally, we have determined the growing velocity of two of the most representative species found and the presence or absence of degradative enzymatic activities.
M T De Troya, A M Navarrete
Tentative method of testing wood preservatives against blue staining
1977 - IRG/WP 259
The blue stain of sawn wood is still a real problem in Poland. Although a preservative based on sodium orthophenylphenoxide has been introduced into sawmill practice, and the technology of wood protection developed with it, new information has been obtained concerning blue stain in wood material destined for export. In order to select new chemicals or to improve the effectiveness of the ones in current use it is necessary initially to carry out laboratory tests of the prepared chemicals to determine their efficiency.
E Tarocinski, O Lewandowski, M H Zielinski
Rapport sur l'activité du CNE/TC 38 'Méthodes d'essais des produits de préservation du bois'
1980 - IRG/WP 279
Blue stain in timber in service. Results of co-operative tests to compare different artificial weathering systems 1981-82
1983 - IRG/WP 2193
The paper describes results of the third phase of co-operative laboratory experiments comparing the effects of different artificial weathering systems on chemicals to control blue-stain in service. Atlas, Xenotest and Marr equipments are shown to give essentially the same results for 5 of the 6 chemicals tested.
A F Bravery, D J Dickinson
Rapport sur l'activité du CEN/TC 38
1983 - IRG/WP 2204
The influence of previous anti-blue-stain preservative treatments on the fixation of CC in spruce
1997 - IRG/WP 97-30134
Freshly cut and kiln dried spruce boards were treated with 4 different anti-blue stain preservatives (ABP). After a period of 10 days allowing the samples to dry and fixate, the samples were treated with CC (chromium, copper formulation) using a vacuum pressure cycle. After impregnation the wood was steam fixed. A submersion leaching test showed differences in the leachable quantity of copper and chromium. When related to the retention of both salts after impregnation, no differences could be found between samples previously treated with anti-blue-stain preservatives and untreated samples. However, the retention of CC diminished significantly by application of quaternary ammonium compounds.
M Van der Zee, W J Homan
Detection of semi-quantitative and qualitative enzymatic activities of blue-stain fungi
2000 - IRG/WP 00-10347
Blue-stain, produced in forests, continues to be a problem in countries of moderate climate. In forestry, in certain geographical areas of Spain, it has been observed that anti-sapstain products have not always been efficient, as their fungicidal effectiveness varies on occasion, depending on the species of wood and microbiota that exist in the region. It is not always easy to identify the species causing this damage. Therefore, the object of this study was the grouping of diverse isolates according to the detection of simple enzymatic activities, following a simple and rapid method of application such as API-ZYM. 36 strains of Ceratocystis spp, isolated from divers species of Pinus spp., have been tested. The results were contrasted with the activities detected in the same conditions in Pullularia pullulans and Sclerophoma pityophila. To do this, these strains were inoculated in culture broths with a basic saline Eggins and Pugh medium, to which 1% sawdust of Pinus sylvestris was added in one trial. Another test was made with a mixture of the most frequent monosaccharides in woody cell-walls (glucose, mannose, galactose, arabinose, and xylose) at 1%. After 20 days of incubation, the extracts were centrifuged, and inoculated in microtubes series of API-ZYM. The analysis of the principal components, carried out with the results obtained, showed that the sawdust induces enzymatic activities implicated in the degradation of polysaccharides such as in a-mannosidase, a-galactosidase, b-glucuronidase, b-glucosidase and b-galactosidase, which appeared as the most weighty specific factors in the dispersion of data on the first two principal axes. Different strains of Ceratocystis also showed similar or greater activity than those of P. pullulans and S. pityophila, which suggests that the latter might be more virulent than the rest of the strains assayed.
M T De Troya, F Llinares, D Muñoz-Mingarro, M J Pozuelo, N Acero, C Rodríguez-Borrajo, A M Navarrete
Rapport sur l'activité du CNE/TC 38 'Méthodes d'essais des produits de préservation du bois'
1977 - IRG/WP 288
Wood extractive concentration and sem examination of pretreated southern yellow pine wood chips with blue-stain fungi for mushroom production
2001 - IRG/WP 01-10407
Mushroom-producing white-rotting basidiomycetes either do not colonize or else colonize very poorly on freshly prepared southern yellow pine wood chips. This study evaluates the resinous extractive content of southern yellow pine before and after treatment with colorless mutant blue-stain fungi. The blue-stain fungi penetrate into the sapwood of southern yellow pine and utilize nonstructural resinous extractives, simultaneously reducing the total resinous extractive content. Scanning electron microscopic examination showed that heavy mycelial growth with good sporulation occurred on the surface of wood chips within 2 days and in parenchyma cells within 6 days. Ophiostoma spp. removed 61.1% to 99.9% of the extractives from the southern yellow pine wood within a period of 4 to 5 days. We conclude that white-rot basidiomycetes can easily colonize and produce fruiting bodies on treated southern yellow pine wood wastes.
S C Croan, J Haight
Fungicidal properties of boron containing preservative Borosol 9
2004 - IRG/WP 04-30348
The fungicidal properties of new boron containing wood preservative Borosol 9 is described in this paper. These properties were of particular interest as this new boron containing preservative, exhibit very good performance against wood damaging insects. But because the tested boron formulation contain also nitrogen compounds, we wanted to verify if nitrogen as a nutrient could promote growth of wood rotting and blue stain fungi. Fungicidal activity of the boron based wood preservative Borosol 9 was evaluated according to the standard EN 113 procedure. Samples made of Norway spruce were brushed two times with 10% aqueous solution of Borosol 9, air dried, steam sterilized and exposed to the following wood rotting fungi: Coniophora puteana, Gloeophyllum trabeum and Lentinus lepideus. After 16 weeks of exposure the specimens were isolated and their mass losses were determined. After this respective period, the treated wood samples lost on an average less than 1 % of their initial mass. Parallel to this experiment, blue stain testing according to the EN 152-1 procedure was performed. Specimens brushed with Borosol were for six weeks exposed to blue stain fungi Aureobasidium pullulans and Sclerophoma pithyophila. After testing period the specimens were isolated and anti blue stain efficacy was determined visually. Both tests showed that Borosol 9 has fungicidal properties. Preservative, containing the boric acid - alkanolamine complex did not enhance fungal decay or growth. On the contrary, they showed high activity against wood decay and blue stain fungi.
G Babuder, M Petric, F Cadež, M Humar, F Pohleven
Antagonistic effect of some mycorrhiza fungi as biological control of blue-stain
1987 - IRG/WP 1314
This report discussed the possibility of using some mycorrhiza fungi as biological control of blue-stain. The results show that new bio-technological possibilities are opening, because, by cultivating antibiosis fungi in fermentor, it is possible to prepare extracts which can then be used as the natural preservative to control the blue-stain in wood.
Biological control of blue stain on wood with Pseudomonas cepacia 6253. Laboratory and field test
1989 - IRG/WP 1380
Pseudomonas cepacia strain 6253 was tested as a biological control agent on wood samples under laboratory conditions, as well as in the field. In the laboratory this bacterium controlled blue stain on Pinus radiata, but field test were not totally satisfactory. However, after 2 months of field test, the test samples were 1/3 to 1/2 less stained then the control samples.
Degradation of the normal fibre walls of rubberwood (Hevea brasiliensis) by the tropical blue-stain fungus Botryodiplodia theobromae
1998 - IRG/WP 98-10286
Rubberwood was examined by light microscopy and transmission electron microscopy (TEM) after exposure to the common tropical sapstain fungus Botryodiplodia theobromae for four weeks to study hyphal colonisation of wood cells and to determine if this fungus also degraded lignified normal fibre cell walls in addition to the walls of non-lignified elements. Light microscopy revealed relatively large diameter hyphae to be abundantly present in parenchyma cells. The hyphae were also present in other types of wood cells, including fibres. TEM provided evidence of fibre wall degradation in the normal rubberwood in the form of lumen wall erosion (type-2 soft rot decay). These observations suggest that the ability of B. theobromae to degrade lignified wood cells walls should be viewed with concern when utilising rubberwood which has been severely sapstained, particularly after prolonged exposure to this fungus.
A A H Wong, A P Singh
A summary of work carried out to compare natural and artificial weathering for preconditioning test specimens in testing anti-stain chemicals for wood in service
1976 - IRG/WP 266
Since 1972 work has been in progress within CEN to establish a European standard for the testing of wood preservatives designed to prevent blue-staining of wood in service. The method is based on the Butin test and involves pre-weathering of the samples prior to biological testing. The weathering regime employed is 6 months outside exposure from March to October. This imposes severe limitations on the number of tests that can be carried out each year and has prompted considerable interest in an artificial weathering procedure which can be used instead of natural weathering. Recently four European laboratories (EMPA, BAM, IC, PRL) have been involved in assessing artificial systems (Xenotest, Marr, Gardener wheel, weathering tunnel) and this report has been prepared at the request of CEN in order to assess the accumulated data and make recommendations back to the CEN. This document presents only a brief account of the work and fuller details can be obtained directly from the laboratories concerned.
D J Dickinson, A F Bravery
Bacteria as possible organisms for biological control of blue stain
1988 - IRG/WP 1339
The article discusses the possibilities of biological control of blue stain. Besides using some antagonistic fungi, the possibility of using antagonistic bacteria, which offer still greater possibilities, should not be overlooked. Tests performed have shown that some bacteria from the genera Streptomyces and Pseudomonas have a strong antagonistic effect of blue stain.
Blue stain resistance of exterior wood coatings as a function of their typology
1998 - IRG/WP 98-20145
Paints and wood stains were evaluated on their blue stain resistance using both EN 152 method and the reverse method. The typology of these exterior coatings was varied including standard and high solid solvent-borne coatings as well as different types of waterborne coatings. For the water-borne acrylic, alkyd based and hybrid coatings both applied as opaque primer paints and as decorative wood stains a range of synthetic resins were used. Though some components like dryers or bactericides are present in a number of formulations examined, a clear tendency of dependence of blue stain resistance on the typology of the coating seems obvious when evaluating blue stain development in an early stage. Longer exposures to test fungi fade away the effect of resin and indicate the role of a chemical protection of the coating.
J Van Acker, M Stevens, C Brauwers, V Rijckaert, E Mol
Report of activity of CEN/TC 38: Test Methods for Wood Preservatives
1987 - IRG/WP 2287
Rapport sur l'activité du CEN/TC 38 "Méthodes d'essais des produits de préservation du bois"
1982 - IRG/WP 2188
Tolylfluanid - fungicide against blue stain in service
1992 - IRG/WP 92-3736
Physical and chemical properties and efficacy of Tolylfluanid are compared with the properties of Dichlofluanid. Whereas the difference in the molecular structure influences the physical properties significantly, the efficacy of both fungicides is comparable. The toxicological and ecotoxicological profile of Tolylfluanid is summarised.
Degradation of the gelatinous-layer in aspen and rubber wood by the blue stain fungus Lasiodiplodia theobromae
1996 - IRG/WP 96-10168
Studies on the degradative ability of the blue stain fungus Lasiodiplodia theobromae Pat. have shown several strains to cause significant weight losses (i.e. ca 20%) in the temperate and tropical wood species, aspen (Populus tremula) and rubber wood (Hevea brasiliensis). In addition to the consumption of soluble carbohydrates and extractives, major changes in the ultrastructure of fibre cell walls was apparent with rapid attack of the gelatinous layer noted. In both wood species following G layer degradation, early wood fibres showed true cell wall degradation with pronounced erosion attack suggesting that prior destruction of the G layer afforded greater accessibility and ease of attack of the outer secondary cell layers.
O Encinas, G F Daniel