Your search resulted in 54 documents. Displaying 25 entries per page.
Oxalic acid quantification, oxaloacetase assay and ESI localization of P, C, and Fe from the brown rot fungus Postia placenta
1994 - IRG/WP 94-10063
The mechanism by which brown-rot fungi initiate depolymerization of holocellulose in wood remains unknown. Recently, oxalic acid (OA) has received considerable attention in cellulose breakdown by brown-rot fungi. The OA could serve as a proton donor for hydrolytic or an electron donor for oxidative (Fenton's reaction-H2O2/Fe2+) cleavages of cellulose. The acid may originate via oxaloaceta...
C R Jordan, W V Dashek, T L Highley
Proposed model for the penetration and decay of wood by the hyphal sheath of the brown-rot fungus Postia placenta
1989 - IRG/WP 1391
Scanning electron microscopy (SEM) of Pinus sp. decayed by the brown-rot fungus Postia placenta confirmed the existence of extracellular membranous structures previously described by transmission electron microscopy (TEM). These structures appear to be an integral part of the hyphal sheath and assume a variety of forms including lamellar sheets, fibrils, and vesicles. These structures were observe...
F Green III, M J Larsen, L L Murmanis, T L Highley
Early detection of brown-rot decay in southern yellow pine using immunodiagnostic procedures
1990 - IRG/WP 2356
Immunodiagnostic procedures have been used to detect incipient decay of southern yellow pine by six common brown-rot fungi. Rabbit polyclonal antibodies were raised to liquid culture fractions of the six fungi. The antibodies, after preadsorption to sawdust, were tested in particle agglutination assays, immuno-dot blot, and ELISA for their·ability to detect the decay organisms when they were grow...
C A Clausen, F Green III, T L Highley
Evaluation of bacteria for biological control of wood decay
1990 - IRG/WP 1426
Laboratory soil-block and agar-block tests were carried out to evaluate the efficacy of bacteria as biological control agents against 5 brown-rot and 3 white-rot fungi. Pretreatment of Southern pine and sweetgum with a bacterial solution prevented decay in agar-block tests. However, the bacteria were generally ineffective in preventing decay in Southern pine, Douglas-fir, sweetgum and yellow popla...
R Benko, T L Highley
The effect of precolonisation of blocks with common pole resident fungi on subsequent biological control of Lentinus lepideus by Trichoderma spp
1989 - IRG/WP 1387
Results of previous field studies have indicated that the spread of Trichoderma throughout the groundline regions of the interiors of creosoted poles are adversely influenced by the presence of large populations of resident mould organisms. Failure of the control fungus to develop and colonize all of the decay susceptible groundline region means that sucessful control of decay is most unlikely. Th...
A Bruce, T L Highley
Control of sapwood-inhabiting fungi by fractionated extracellular metabolites from Coniophora puteana
1991 - IRG/WP 1494
The objective of this study was to test the fractionated metabolites released by Coniophora puteana for their antagonistic activity against the sapstain fungi Ceratocystis coerulescens and Aureobasidum pullulans, and the molds Asperigillus niger and Penicillium spp. The acetone-soluble fraction obtained from the culture filtrate prepared from Coniophora puteana grown on 6% malt extract agar inhibi...
S C Croan, T L Highley
Hemicellulosic induction of oxalic acid in Postia placenta
1994 - IRG/WP 94-10060
Most studies suggest that enzymes produced by brown-rot fungi are too large to penetrate sound wood structures, even after decay begins. Thus, nonenzymatic agents have been proposed to initiate brown-rot decay. We have reported that the brown-rot fungus Postia placenta MAD-698 initiates a 2-fold decrease in wood pH within 7 days of colonization which is mediated by production of oxalic acid. Strai...
F Green III, M Larsen, T L Highley
Trials of new treatments for prevention of kiln brownstain of white pine (Pinus strobus)
1995 - IRG/WP 95-30068
White pine (Pinus strobus) often develops a surface brown oxidative stain when kiln dried. Such stain downgrades high quality lumber and is most likely to occur when fresh, unseasoned lumber is stacked during warm weather prior to kiln drying. Use of reducing agents or pH alteration has been successful, but may have some practical limitations for general use. This study attempted to prevent browns...
E L Schmidt, E Christopherson, T L Highley, M H Freeman
The long road to understanding brown-rot decay. A view from the ditch
1995 - IRG/WP 95-10101
Interest in understanding how brown-rot fungi decay wood has received increasing interest in recent years because of a need to identify novel targets that can be inhibited for the next generation of antifungal wood preservatives. Brown-rot fungi are unique in that they can degrade holocellulose (cellulose and hemicellulose) in wood without first removing the lignin. Furthermore, they degrade holoc...
F Green III, T L Highley
Targeted inhibition of wood decay (Using everything but the kitchen sink)
1997 - IRG/WP 97-10203
Low molecular weight oxidative decay agents have been implicated in the degradation of wood by brown-rot decay as evidenced by chemical analysis of brown-rotted wood and detection of oxalic acid and hydroxy radicals. Fenton chemistry (H2O2 / Fe++) is often proposed as the mechanism for generating hydroxy radicals. Previous authors have shown iron to enhance the brown-rot hydrolysis of wood, while ...
F Green III, T A Kuster, T L Highley
Laboratory studies on control of sapstain and mold on unseasoned wood by bacteria
1991 - IRG/WP 1493
A malt-agar and nonagar laboratory test was used to evaluate the efficacy of bacterial preparations as biological control agents against several sapwood-inhabiting fungi. Both nonsterilized and filter sterilized bacteria preparations prevented attack by the sapwood-inhabiting fungi. Streptomyces rimosus was the most effective bacteria, giving good protection, with a 1-hr soak in a filter-sterilize...
T L Highley, R Benko, S C Croan
Siderophore production by Trichoderma spp. and its importance in the biological control of wood decay fungi
1994 - IRG/WP 94-10070
Competition for iron as well as other micro-nutrients is an essential component of the microbial ecology of many ecosystems. A wide range of micro-organisms including fungi and bacteria have been shown to increase their ability to efficiently capture iron through the production of specialised iron chelating compounds called siderophores. Since iron is in low supply in wood and has been implicated ...
U Srinivasan, A Bruce, T L Highley
Efficacy of fumigants in the eradication of decay fungi implanted in southern pine timbers
1986 - IRG/WP 3365
Southern pine timbers (15.2 cm x 15.2 cm x 4.26 m) were fumigated at midlength to evaluate the effectiveness of the fumigants chloropicrin, Vapam, Diazomet, Busan 40, Vanicide 51, Vanicide TH, sodium bisulfite, and ethanolamine in eradication of decay fungi. The fumigants were introduced into 2.54 cm holes which were closed immediately with rubber stoppers. Movement and persistence of lethal conce...
T L Highley, W E Eslyn
Properties of cellulose degraded by the brown rot fungus, Postia placenta
1988 - IRG/WP 1350
To gain further understanding of the nature of the cellulose depolymerizing agent or agents of brown-rot fungi, brown-rotted cellulose was chemically and physically characterized. Various culture conditions, such as low nitrogen and elevated oxygen levels, did not induce degradation of cellulose by Postia placenta in liquid cultures. Therefore, brown-rotted cellulose for analysis was prepared by a...
T L Highley, R E Ibach, T K Kirk
Antagonistic effect of Trichoderma spp. against basidiospores
1993 - IRG/WP 93-10027
All screening of potential biocontrol agents of wood decay fungi have previously been used against basidiomycete mycelium. Similarly, experiments designed to evaluate the mechanisms involved in antagonism (soluble metabolites and volatile antibiotics) between biological control agents and target fungi have always been carried out on mycelial inoculum. Basidiospores are a primary source of infectio...
U Srinivasan, T L Highley, S C Croan, A Bruce
Hydrolysis of bordered pits during colonization of conifers by brown-rot fungi
1995 - IRG/WP 95-10103
Brown-rot decay results in rapid reduction in degree of polymerization (DP) of holocellulose with concomitant strength loss (MOR) without removing lignin. Development of new methods of wood protection will require focusing on early events in the sequence of depolymerization. Bordered pit membranes (sapwood) represent a readily available source of non-lignified carbohydrate, ie. pectin and cellulos...
F Green III, J L Tschernitz, T A Kuster, T L Highley
Antagonistic properties of Gliocladium virens against wood attacking fungi
1996 - IRG/WP 96-10162
Gliocladium virens has shown good antagonism against decay fungi in agar medium and in wood blocks. Gliotoxin produced by Gliocladium virens is associated with biocontrol of some plant diseases, but its importance to biocontrol of wood-attacking fungi is unknown. We investigated the ability of gliotoxin-producing (GLT+) isolates of Gliocladium virens and gliotoxin-deficient (GLT-) mutants of Glioc...
T L Highley, H S Ananthapadmanabha, C R Howell
Immuno-scanning electron microscopic localization of extracellular polysaccharidases within the fibrillar sheath of the brown rot fungus Postia placenta
1991 - IRG/WP 1497
Extracellular polysaccharidases of the brown-rot fungus Postia placenta were localized using colloidal gold labeled monoclonal antibodies to the B-1,4-xylanase (32-36kDa) fraction of Postia placenta. Postia placenta was grown from agar onto glass coverslips, immunolabeled with or without prior fixation, and examined by SEM. Enzymes were localized on the hyphal surface and on the clumped fibrillar ...
F Green III, C A Clausen, M J Larsen, T L Highley
Effect of wrapping on movement of chloropicrin, Vapam, and Vanicide TH in southern pine timbers
1987 - IRG/WP 3411
Important fungi that decay wood protucts were "inoculated" into nonpressure-treated southern pine timbers as vapor-sensing agents to evaluate the effect of wrapping on the movement and persistence of fungitoxic concentrations of chloropicrin, Vapam, and Vanicide TH in the timbers. Fumigant movement and persistence in the timbers was enhanced by wrapping the timbers in polyethylene after fumigation...
T L Highley
Distribution of boron from fused borate rods in Douglas-fir transmission poles
1996 - IRG/WP 96-30112
The diffusion of boron from fused borate rods (disodium octaborate tetrachydrate) was monitored over 42 months in CCA-treated Douglas-fir transmission poles. The boric acid equivalent was estimated by the curcumin/salicylic acid color test on increment cores removed from the poles. Moisture content of the poles was quite variable but was always above 20 percent. The percent of increment core lengt...
T L Highley, F Green III, W F Finney
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
Extracellular carbohydrate production by isolates of Postia (=Poria) placenta
1989 - IRG/WP 1388
A monokaryotic strain of Postia (=Poria) placenta, ME20, which is unable to degrade wood, also failed to produce extracellular polysaccharide when grown in liquid culture, regardless of carbon source or concentration. Other isolates of Postia placenta, including another monokaryon and a hybrid of this monokaryon with ME20, produced large quantities of this material. The polysaccharide consisted pr...
J A Micales, A L Richter, T L Highley
Movement of chloropicrin, Vapam, and methylisothiocyanate in southern pine and Douglas fir timbers
1987 - IRG/WP 3410
Douglas fir and southern pine timbers, 15.2 x 15.2 x 426 cm³ (6-in x 6-in x 14-ft), were "inoculated" with brown-rot and white-rot fungi as vapor-sensing agents to evaluate the movement and distribution of fungitoxic concentrations of chloropicrin, Vapam, and methylisothiocyanate (MIT) over a 20-week period. Residual fumigant in timbers was determined by a bioassay with Gloeophyllum trabeum. The ...
T L Highley
Antagonism of Gliocladium virens against wood decay fungi
1995 - IRG/WP 95-10102
Antagonistic abilities of a commercial biofungicide, Gliocladium virens (GL-21, Grace) were evaluated against three white-rot fungi, Trametes versicolor, Phlebia brevispora, Irpex lacteus, and three brown-rot fungi, Postia placenta, Neolentinus lepideus, Gloeophyllum trabeum. In dual culture of Gliocladium virens and wood decay fungi, Gliocladium virens rapidly overgrow the decay fungi and killed ...
T L Highley, L Ferge
Borate diffusion from fused borate rods in douglas-fir transmission poles
1994 - IRG/WP 94-30042
Pressure-treated utility poles have given many years of excellent service, but their lifetime is often shortened by internal decay of the untreated heartwood center, particularly in refractory species, such as Douglas-fir. This paper reports the distribution of boron from fused borate rods installed in CCA-treated Douglas-fir transmission poles. The boric acid equivalent was roughly monitored by t...
T L Highley, W Finney, F Green III