Your search resulted in 57 documents. Displaying 25 entries per page.
Some experiences with attack of microorganisms on wooden constructions supporting foundations of houses and bridges
1997 - IRG/WP 97-10232
Reconstructions of bridges and public buildings or damage of houses during the construction of subway lines in Berlin have led to a number of inspections of wooden foundations, mostly pine or spruce piles, representing service lives of between ca. 70 and 140 years. In all cases bacterial attack was found both in wood submerged in ground water and in surface water. The extent of deterioration diffe...
M Grinda
Enzyme systems of bacterial isolates from ponded logs - Potentials of pectin and/or starch degradation
2000 - IRG/WP 00-10378
This paper deals with the degradation potentials of wood constituents by the bacterial isolates from ponded logs. The potentials to degrade pectin as a constituent of pit-tori as well as starch existing in ray parenchyma cells in the areas of sap- and transition wood with the isolates were examined. The pectinase activity was investigated by means of the degradation degree of a carrot strip used a...
S Doi, S Ohta
A new method for the study of microbiological decay of wood in a strictly anaerobic environment
1988 - IRG/WP 2319
Recent work has suggested that strictly anaerobic bacteria may play a role in the biodeterioration of wood, particularly in aqueous environments. However, no suitable test methods exist for the investigation of this hypothesis. An aqueous minimal medium in specifically adapted conical flasks was sterilised, gassed using a 5.5% H2; 31.8% C02; 62.7% N2 gas mixture to remove oxygen and transferred to...
G M Rogers, A A W Baecker
A light and electron microscopic study of decayed CCA-treated radiata pine (Pinus radiata) wood from a cooling tower
1994 - IRG/WP 94-10056
An inspection of an industrial cooling tower in New Zealand showed surface decay of 12 year old Pinus radiata wood panels treated with CCA preservative to a retention of around 15 kg/m³ of salt. Wood decay micromorphology typical of that caused by soft rot fungi, white rot fungi, 'stripy' and 'v-shaped' erosion bacteria and cavitation bacteria were all commonly...
A P Singh, R N Wakeling, D R Page
Microscopic characteristics of microbial attacks of CCA-treated radiata pine wood
1993 - IRG/WP 93-10011
Light and electron microscopic observations were made of CCA-treated radiata timbers, which had been placed in service in a vineyard soil as supporting poles and as part of a house pile, to determine the cause of their deterioration. The house pile had failed in service after between 9 and 13 years and was of particular interest because decay was more severe in deeper regions than at the surface a...
A P Singh, R N Wakeling
Accelerated decay tests on DNBP-treated Pinus patula and Eucalyptus grandis
1987 - IRG/WP 3441
Blocks (10 x 10 x 5 mm³) of Pinus patula and Eucalyptus grandis were impregnated to 0, 1.5, 3.0 and 4.5 kg/m³ 2-sec-butyl, 4, 6 dinitrophenol (DNBP). They were monitored microscopically and for weight losses over 16 weeks against monocultures of Coriolus versicolor and Coniophora puteana. Treated ministakes (10 x 10 x 100 mm³) and blocks in soil contact were similarly monitored to determine wei...
L D Abraham, A A W Baecker
Copper storage in the digestive caecae of Limnoria tripunctata and Limnoria quadripunctata (Crustacea: Isopoda) tunnelling in CCA treated and untreated wood in laboratory cultures
1998 - IRG/WP 98-10257
Digestive tract tissues of Limnoria quadripunctata Holthuis and Limnoria tripunctata Menzies, tunnelling untreated and CCA treated Scot's pine sapwood under laboratory conditions were examined using X-ray microanalysis and transmission electron microscopy. Populations of both Limnoria species tunnelling treated and untreated wood stored copper within their digestive caecae in the form of ...
C Wykes, A J Pitman, S M Cragg
Bacterial brown stain on sawn timber cut from water-stored logs
1992 - IRG/WP 92-1532
Brown stains which appear on the surface of sawn radiata pine cut from water-stored logs were identified as tannin-like compounds. They are derived from bacterial breakdown of flavanoid-glucosides. When timber is sawn from infected logs, the free flavanoids migrate to the wood surface as the timber dries. There, they condense and oxidise to form permanent brown discolourations. Stains occurred on ...
M E Hedley, R Meder
Effect of volatiles from bacteria and yeast on the growth and pigmentation of sap-stain fungi
2000 - IRG/WP 00-10331
Sapstain fungi cause deterioration of wood due to colonisation by pigmented hyphae but without producing significant strength losses. This is due to the production of melanin in the fungal cell walls of the staining fungi. Any biological control strategy targeted against this type of deterioration would therefore be considered successful if it inhibited either fungal growth or pigment production. ...
A Bruce, R E Wheatley, S Verrall
Bacteria are important degraders of cooling tower timbers: New Zealand experience
1995 - IRG/WP 95-10128
Microscopic examinations of CCA-treated Pinus radiata timbers in industrial cooling towers in New Zealand showed bacteria and soft rot fungi to be primarily responsible for the decay of these timbers. Of these micro-organisms, erosion bacteria appeared to be most widespread, attacking wood cell walls independently as well as together with tunnelling bacteria and soft rot fungi. Tunnelling bacteria...
A P Singh, R N Wakeling
Effect of test site, preservative and wood species on decay type Glenbervie pastoral and radiata pine forest sites
2000 - IRG/WP 00-30248
Pinus radiata stakes were treated with 0.8, 1.2, 1.8, 2.7 and 4.1 kg/m3 of CCA and Fagus sylvatica with 2.7, 4.1 and 6.1 kg/m3 of CCA. Both wood species were also treated with equivalent retentions of a copper plus triazole preservative (CT) (0.89, 1.3, 2 and 3 kg/m3 of copper for pine & 2.5 and 4 for beech) and chlorothalonil plus chlorpyriphos in oil (CC) (1.4, 2.1, 3.2 and 4.8 kg/m3 of chlo...
R N Wakeling
Assessment of treated wood leachates genotoxicity with a bacterial test
1997 - IRG/WP 97-50089
Genotoxicity is known as the damage caused by environmental stressors (biological, chemical and physical) on the genetic material of an organism. This toxicological effect can be assessed by a lot of biological assays and especially by bacterial tests. These tests are frequently performed on environmental samples or on pures substances and are in that case, strongly correlated to the carcinogenic ...
P Marchal, C Martin
Destruction of two tropical timbers by marine borers and micro-organisms in Goa waters (India)
1992 - IRG/WP 92-4176
The paper deals with the pattern of microbial attack in relation to marine borer damage of test panels of African rosewood and Brazilian jackwood exposed in Goa waters (Western India) for a period of seven months. The degradation of wood cell walls in both the timber samples occurred due to infestation of soft-rot fungi and tunnelling bacteria. African rosewood, which was severely damaged by tered...
L N Santhakumaran, A P Singh
Attempts to isolate tunnelling bacteria through physical separation from other bacteria by the use of cellophane
1992 - IRG/WP 92-1535
During attempts to isolate tunnelling bacteria in pure culture, physical separation from other bacteria was successfully achieved by the use of cellophane. Cellophane was used in liquid cultures as a substrate for tunnelling bacteria that were present in a mixture with other bacteria. By tunnelling into cellophane, TB were physically removed from contaminating bacteria which could then be removed ...
T Nilsson, G F Daniel
Tunnelling bacteria
1983 - IRG/WP 1186
The micromorphology of decay in wood caused by a certain group of single-cell bacteria, called tunnelling bacteria (TB), is described. TB are characterised by their tunnelling ability within the secondary cell walls of wood fibres. Pure cultures of TB have not yet been obtained although the typical decay patterns can be reproduced using mixed bacterial cultures. Some indications of lignin degradin...
T Nilsson, G F Daniel
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
Hyphal tunnelling of belian (Eusideroxylon zwageri) wood cell walls
1996 - IRG/WP 96-10152
Belian (Eusideroxylon zwageri) is highly regarded among the naturally durable Malaysian hardwoods. Visual inspections at the groundline of belian transmission poles from Sarawak, Malaysia, showed only surface decay of wood after 20 years in service. The cause of decay in belian was investigated by light and transmission electron microscopy. Light microscopy of transverse sections of surface tissue...
A P Singh, A H H Wong
Standard principles of testing termiticides: A discussion paper
1991 - IRG/WP 1502
Recent restrictions and banning of termiticides such as organochlorines in some countries has focussed attention on the need for new and novel compounds as termiticides. However, this poses problems for both wood preservative manufacturers and termitologists. Test procedures have to be devised to evaluate the new termiticides so that the tests are practical, encourage vigorous termite activity, an...
J R J French
16S rRNA Analysis of the Bacteria Associated with Biocide Degradation
2004 - IRG/WP 04-10543
The bacterially mediated degradation of the new anti-fungal biocide, bethoxazin, was studied in vitro, by means of 16S rRNA PCR-amplification and cloning techniques. Woodblocks impregnated with a subtoxic concentration of bethoxazin were incubated in compost, and the micro-organisms associated with the wood after 6 and 12 weeks was studied. It was found that after 6 weeks the wood contained a la...
D F Wallace, D J Dickinson
The Bacterial Biotransformation of IPBC
2002 - IRG/WP 02-10437
The bacterial biotransformation of the biocide IPBC, widely used as an antisapstain wood preservative, was investigated in bacteria isolated from failed wood, soil experiencing IPBC wash-off, and John Innes No. 2 compost. Nine strains of bacteria were isolated, belonging to the genera Alcaligenes, Enterobacter, Microbacterium and Pseudomonas. The sole organic degradation product in an enteric bact...
S R Cook, J Sullivan, D J Dickinson
Ingestion of wood-degrading micro-organisms
1991 - IRG/WP 4169
An ultrastructural study was carried out on the digestive tract contents of Limnoria lignorum, frass, gallery walls and surface structures of the animals. The purpose of the study was to determine whether wood-degrading bacteria, fungi and other microbes and/or wood degraded by these microbes were present in gut regions and therefore could provide indirectly a nutritional source for Limnoria. Both...
G F Daniel, S M Cragg, T Nilsson
The effect of concrete embedment on CCA treated hardwood and softwood timbers
1985 - IRG/WP 3340
Small size stakes of Eucalyptus maculata and Pinus elliottii were treated with CCA to various retentions and embedded in concrete collars containing varying amounts of a fungicide additive. During the 30 month trial period stakes were removed after 12, 18, 24 and 30 months and assessed for residual strength. Stakes which showed significant strength reductions were microscopically examined for the ...
L E Leightley, G A Willoughby
Biological control of sapwood-inhabiting fungi by living bacterial cells of Streptomyces rimosus as a bioprotectant
1992 - IRG/WP 92-1564
The objective of this study is to evaluate the efficacy of antifungal activity of living bacterial cells for the protection of wood against sapwood-inhabiting fungi. The following sapwood-inhabiting fungi were selected: sapstain --Ceratocystis coerulescens, Ceratocystis minor, Ceratocystis pilifera, and Aureobasidum pullulans; mold fungi --Aspergillus niger, Penicillium spp, and Trichoderma spp. L...
S C Croan, T L Highley
Ability of heartwood extractives to inhibit the growth of a bacterial symbiont of Teredo navalis
2000 - IRG/WP 00-10369
Shipworms are important destroyers of wood in the marine environment, and wood users have long sought methods for preventing or limiting their attack. While heavy -duty wood preservatives are highly effective against these organisms, there is increasing concern about risks to non-target organisms. This has resulted in a gradual shift away from broadly toxic materials to either alternative material...
C S Love, A R Sipe, S C Cary, J J Morrell
New Observations and Interpretation for Tunnelling Bacteria Decay
2006 - IRG/WP 06-10579
Decay micromorphology was studied systematically for diversely preservative treated Pinus radiata and Fagus sylvatica 20 x 20 x 500 mm stakes across 13 in-ground field test sites, during a 6.5 year exposure. Sites were selected to maximise occurrence of a diverse range of decay types. Micromorphology that suggested orientation of tunnelling bacteria with the cellulose microfibrils of the S2 and S1...
R Wakeling