Your search resulted in 26 documents. Displaying 25 entries per page.
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...
T Singh, B Kreber, R N Wakeling, A Stewart
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 growt...
C Chittenden, R N Wakeling, B Kreber
In vitro studies on the effect of chitosan on mycelial growth and spore germination of decay fungi, moulds and staining fungi
2004 - IRG/WP 04-10507
The effect of solubilised, low molecular weight chitosan on established mycelial growth of a range of decay fungi, moulds and staining fungi was investigated using nutrient medium amended with different concentrations of chitosan that ranged from 0.1 to 0.4% weight per volume (%w/v). Also, spore germination of Trichoderma harzianum and Leptographium procerum was examined on chitosan amended nutrie...
C Chittenden, B Kreber, N McDowell, T Singh
Effect of wood moisture on ability of Sphaeropsis sapinea to colonise Pinus radiata
1999 - IRG/WP 99-10311
The factors influencing colonisation of unseasoned radiata pine logs by sapstaining fungi which can result in detrimental wood discolouration, are being explored. The objective of the current study was to determine the effect of wood moisture content on fungal growth and wood colouration (melanisation).
Five replicate trials were set up using increment cores (10mm diameter) which were taken from ...
B Kreber, D R Eden, R N Wakeling, C M Chittenden, J G Van der Waals, B Carpenter
Evaluation of New Zealand staining fungi for degradation of radiata pine
1999 - IRG/WP 99-10310
This investigation sought to determine the potential of selected NZ staining fungi to induce weight loss and changes in toughness (impact bending strength) and composition in unseasoned radiata pine sapwood. Furthermore, assays were performed to eveluate enzyme production by staining fungi. Sets of side-matched specimens were inoculated with Ophiostoma floccosum, Sphaeropsis sapinea and O. plurian...
A Schirp, R L Farrell, B Kreber
The use of immunofluorescence labelling for detecting Ophiostoma piceae in radiata pine
1998 - IRG/WP 98-10268
The primary objective of the current investigation is to understand fungal interactions of dominant sapstaining fungi in radiata pine using confocal laser scanning microscopy (CLSM).
In the current paper, an immunofluorescence labelling technique was developed for detection of Ophiostoma piceae using a monoclonal antibody. The primary antibody was labelled with Oregon green 514 Goat anti-mouse Ig...
Ying Xiao, B Kreber, C Breuil
The efficacy of Sentry® as a treatment for the control of sapstain in pre-infected radiata pine
2001 - IRG/WP 01-30260
Experiments were conducted to determine the efficacy of Sentry® when used to control sapstain fungi on radiata pine branch billets stored under high fungal hazard conditions. Prior to antisapstain treatment, the billets were pre-infected with a mixed inoculum of staining fungi and held from zero to 10 days at 25°C and 75% relative humidity. This was done to produce billets with different degrees...
C Chittenden, J G van der Waals, B Kreber, R N Wakeling
Effect of mobile fungicides on fungal pre-infection in radiata pine billets.
1999 - IRG/WP 99-30191
In New Zealand, fungal infection of logs begins directly after felling and whilst severe degrade can be prevented if antisapstain-treated within 24 hours, such short turn-around times of logs are not always practicable. However, conventional antisapstain formulations in use only provide an envelope of protection on the log surface but are unable to control pre-infections below the surface. The obj...
D R Eden, T Singh, B Kreber
Localized induction of hemlock brownstain by Ophiostoma piceae
1995 - IRG/WP 95-10106
Hemlock brownstain, a coloration disfiguring western hemlock and amabilis fir, causes economic loss in the high-value Canadian export lumber market. Recent work by the author has suggested that wood-sapstaining fungi can induce the formation of brownstain. Ophiostoma piceae, the most frequent staining fungus on western hemlock lumber in B.C., was chosen as a model to investigate fungal participati...
B Kreber
An evaluation of chemical pre-treatments for controlling kiln brown stain in radiata pine
1997 - IRG/WP 97-30124
Clear radiata pine (Pinus radiata D. Don) is widely used for fine millwork owing to its attractive light colour. However, kiln drying of radiata pine sapwood often results in the development of a brown stain causing substantial loss in revenues in New Zealand's high-value export markets. In this study chemical pre-treatments were evaluated for their ability to control the formation of kil...
B Kreber, A McDonald
Biofumigation of sapstaining fungi using natural products
2002 - IRG/WP 02-10428
Control of deep-seated fungal infections in raw logs of radiata pine continues to be a challenge for achieving consistent and satisfactory protection of high value logs destined for export markets. To develop solutions for this problem, a study was undertaken to investigate inhibition of spore germination and growth of sapstaining fungi by volatiles released from a selection of natural products.
...
B Kreber, C Chittenden, R N Wakeling
Advances in understanding the mode of action of methylene bisthiocyanate against Sphaeropsis sapinea
2002 - IRG/WP 02-30284
The importance of arresting sapstain pre-infection in radiata pine in New Zealand, to prevent downstream sapstain in both logs and sawn timbers has been clearly demonstrated. Efforts are being made to improve the efficacy of diffusible antisapstain agents through improved understanding wood/fungicide/fungus interactions. The mechanism of action of methylene bisthiocyanate (MBT) was investigated u...
T Singh, R N Wakeling, B Kreber, A Stewart
Fumigation of New Zealand grown western red cedar for export markets
2001 - IRG/WP 01-30262
The objective of this study was to demonstrate that methyl bromide fumigant penetrates into the centre of western red cedar (Thuja plicata L.) timber to meet the standard for export markets. Kiln dried western red cedar was used and a cavity (50x 30 x 13mm3) was prepared into the centre of each sample board (500 x 200 x 26 mm3 thick). An absorbent sachet used in industry for cross checking that th...
B Kreber, G Durbin, D Wilson
Laboratory trial to identify potential in-forest treatments to control fungal pre-infections of radiata pine logs
2000 - IRG/WP 00-30220
Development of fungal infections of radiata pine logs by wood degrading fungi commences immediately after tree felling. In general, subsequent antisapstain treatments are unable to control fungal degrade on logs where the pre-treatment log storage time exceeds 2-5 days. However, use of an in-forest treatment of logs may be advantageous to log exporters to control fungal pre-infections during the p...
D R Eden, B Kreber, R N Wakeling, J G Van der Waals, C M Chittenden
Effect of bioextracts on colonisation of radiata pine sapwood by three sapstain fungi
2003 - IRG/WP 03-10485
The objective of this study was to investigate the effect of aqueous bioextracts prepared following two-week incubation of forest soil, garden compost and chicken manure respectively, on the ability of Ophiostoma flocossum, Leptographium procerum and Sphaeropsis sapinea to colonise unseasoned radiata pine sapwood.
The research showed that all bioextracts tested retarded the rate of fungal colonis...
J van der Waals, C Chittenden, B Kreber
Assessing the leachability of chlorothalonil and methylene bis thiocyanate from antisapstain treated radiata pine
1998 - IRG/WP 98-30176
Rain wash-off and leaching of antisapstain fungicides from wood may cause pollution of waterways and may also lead to a decrease in the efficacy of a formulation against fungal degrade as chemicals deplete from the timber surface.
In the current study, the leachability of chlorothalonil (CTL) and methylene bis thiocyanate (MBT), the active ingredients of a commercial antisapstain formulation, was...
B Kreber, T L Woods
Characterisations of the mode of action(s) of Methylene bisthiocyanate (MBT) in Ophiostoma floccosum
2005 - IRG/WP 05-10554
Potassium (K+) leakage, oxygen consumption, glucose depletion and level of ATP formation were determined to elucidate the potential target site(s) of MBT on the sapstain fungus O. floccosum. Treatment of O. floccosum with MBT caused an efflux of intracellular K+ ions from the cells, and the rate of leakage increased with increasing MBT concentrations up to a certain value. This observation sugge...
T Singh, B Kreber, A Stewart, M Jaspers
Use of mixed populations of microflora to control sapstain on radiata pine
2002 - IRG/WP 02-10427
Most methods of biological control in the wood products field have focused on the use of single species of fungi or bacteria to control sapstain or decay. The approach taken in this study involved applying soil microorganisms, in combination with nutrients and various adjuvants that collectively form the biological control system.
Radiata pine branch discs, autoclaved or fresh, were dipped in ...
C Chittenden, R Wakeling, B Kreber
Chitosan for wood protection - state of the art
2005 - IRG/WP 05-30378
The aim of this paper was to give a state of the art description of chitosan as a wood protecting agent. Chitosan is a metal free natural compound derived from crustacean shells and is under evaluation as an environmentally benign wood protecting agent. Information from journals states that chitosan may act both fungistatically and at higher concentrations, as fungitoxic, but the mode of action is...
M Eikenes, G Alfredsen, E Larnøy, H Militz, B Kreber, C Chittenden
Variable tolerance of Ophiostoma spp. and Diplodia pinea to commercial antisapstain products
1998 - IRG/WP 98-10266
A recent survey of the occurrence of sapstain fungi in New Zealand, conducted at The University of Waikato, provided the opportunity to examine fungicidal tolerance amongst new isolates. It also enabled a comparison of tolerance amongst new isolates with those used in routine antisapstain screening trials at Forest Research.
A rapid antisapstain laboratory disc trial was used to determine the ext...
D R Eden, C M Chittenden, B Kreber, J G Van der Waals, R N Wakeling, R L Farrell, T Harrington
Effect of origin and orientation of Radiata pine substrates on the development of fungal degrade
2000 - IRG/WP 00-30221
The objective of this study was to determine the influence of different radiata pine substrates on colonisation by sapstain fungi. Freshly-cut branch wood, stem wood and sawn lumber were used to prepare test samples with the largest wood surface area showing a transverse, radial or tangential face. Test samples were evaluated against sapstain fungi using a rapid laboratory antisapstain screening m...
B Kreber, D R Eden, C M Chittenden, B Carpenter, J G Van der Waals
Minimum inhibitory concentration of methylene bisthiocyanate towards selected wood inhabiting fungi in liquid culture and on radiata pine
2001 - IRG/WP 01-30261
The objective of the current study was to determine the minimum inhibitory concentration (MIC) of methylene bisthiocyanate (MBT) towards wood inhabiting fungi common on unseasoned radiata pine (Pinus radiata D. Don). The fungi used were Ophiostoma floccosum, Leptographium procerum, Sphaeropsis sapinea and Trichoderma viride. Fungi were individually inoculated into nutrient media spiked with differ...
T Singh, B Kreber, C Chittenden, R N Wakeling, A Stewart
A microscopic study on the effect of IPBC/DDAC on growth morphology of the sapstaining fungus Ophiostoma piceae
1997 - IRG/WP 97-10191
An exploratory study was performed to probe into fungal/wood/fungicide interactions using Ophiostoma piceae, a common sapstaining fungus on unseasoned radiate pine. Treated (1% solution containing IPBC (0.07% w/w) and DDAC (0.60% w/w)) and untreated radiate pine wafers were inoculated with O. piceae and examined microscopically over a ten days incubation time. The results of the study showed that ...
Ying Xiao, B Kreber
The role of mechanised harvesters in the dissemination of fungal inoculum into radiata pine logs in New Zealand
2002 - IRG/WP 02-10426
A joint research programme has been initiated between Forest Research, New Zealand and Forintek Canada Corp., Canada, to determine the role of mechanical tree harvesters on disseminating fungal inoculum into logs. Mechanical harvesters cause loosening and removal of bark and also damage the surface of the wood with their feed rollers leaving indentations up to several centimetres deep. Results ...
D O’Callahan, B Kreber, A Uzunovic
Decay potential of various New Zealand Phlebiopsis gigantea strains using a soil block method
1999 - IRG/WP 99-10309
The objective of the current study was to determine the decay potential of different strains of Phlebiopsis gigantea using Pinus radiata and European Fagus sylvatica, respectively. A soil block method was used to determine mass weight loss of P. radiata and F. sylvatica following 10 weeks incubation with different strains of P. gigantea. For comparison, Trametes versicolor, Postia placenta, Gloeop...
B Kreber, J G Van der Waals