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1
Jonsell, Mats. "Insects on wood-decaying polypores : conservation aspects /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5627-4.pdf.
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Venables, Caroline E. "The nitrogen economy of wood-decaying basidiomycetes." Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293538.
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Taylor, K. M. "The ecology of myxomycetes within decaying wood." Thesis, University of Bristol, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378784.
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The interiors of 72 decaying branches from a range of tree species were investigated for the presence of myxomycetes. Tree species whose decaying wood yielded myxomycetes included oak, ash, birch, sycamore, silver birch, hazel, .pine and spindle. The only phase of the life cycle isolated directly from within the wood was the uninucleate phase, although aphanoplasmodia did on occasions form on the isolation plates. It was therefore concluded that the uninucleate trophic phase was the most prolonged feeding phase as opposed to the plasmodial phase. Also the predominant type of myxomycete within the decaying wood sampled was the aphanoplasmodial-type. A numerical investigation of the uninucleate myxomycetous cells, flagellates and ciliates yielded by the interior wood of 121 decaying branches, collected from the ground or "aerially" at Leigh Woods, Avon; Wetmoor, Avon; and Weston Big Wood, Avon, revealed numbers of myxomycetous cells up to 64,100 per cm 3 in oak and up to 13,200 per cm 3 in lime. The numbers of uninucleate myxomycetous cells per cm 3 were found to be inversely related to 3 the numbers of non-myxomycetous flagellates and ciliates per cm , possibly reflecting direct competition for bacterial food. The state of decay of the branches was determined by measuring the density and C:N ratio of the wood. These two variables were found to be directly related. No direct relationship between the density of the wood or C:N ratio (as measures of decay) and the numbers of myxomycete uninucleate cells was found. However myxomycetes, non-myxomycetous flagellates and ciliates were more frequently isolated from the lower density (more decayed) wood. A microcosm system representing decaying wood was developed to investigate the position of the myxomycetes in food chains within decaying branches. The uninucleate myxomycetous cells of Ceratiomyxa fruticulosa were found to feed on the bacteria (Aerobacter aerogenes) in the microcosm. There was no evidence that they could directly utilize the cellulose carbon source provided. The fungus (Peniophora guercina) was not noticeably affected by the presence of the other two organisms, although it appeared to have a" deleterious effect on the myxomycete cell numbers. This effect may have been specific to the species of myxomycete and fungus involved. The terminology used to refer to the flagellate and nonflagellate uninucleate trophic cells of myxomycetes is discussed and a new term "myxomonads" is introduced to refer to both the flagellate and non-flagellate cells. The identification of myxoflagellates is also discussed and criteria for their identification listed. The identification of typical myxoflagellates was found to be necessary for their enumeration.
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Jonsson, Mattias. "Dispersal ecology of insects inhabiting wood-decaying fungi /." Uppsala : Swedish University of Agricultural Sciences, 2002. http://diss-epsilon.slu.se/archive/00000064/.
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Thesis (doctoral)--Swedish University of Agricultural Sciences, 2002.Thesis documentation sheet inserted. Appendix reprints three manuscripts and one published paper, three of which are co-authored with others. Includes bibliographical references. Also issued electronically via World Wide Web in PDF format; PDF version lacks abstract, ack., and appendix. One ill. in PDF version is in col.
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Fahmida, Zaman Irin. "Wood decaying fungi gain competitive strength through competition." Thesis, Mittuniversitetet, Institutionen för naturvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-36444.
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Gustafsson, Mårten. "Factors that limit the occurrence of wood-decaying fungi /." Uppsala : Sveriges lantbruksuniv., Inst. för skoglig mykologi och patologi, 2001. http://epsilon.slu.se/avh/2001/91-576-6127-8.pdf.
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Qian, Yuhui. "Study of Basic Wood Decay Mechanisms and Their Biotechnological Applications." Fogler Library, University of Maine, 2008. http://www.library.umaine.edu/theses/pdf/QianY2008.pdf.
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Carranza, Julieta Velazquez. "CULTURAL AND OTHER STUDIES ON THE SPECIES OF FOMITOPSIS WITH ROSE-COLORED CONTEXT (FUNGI, DECAY, BROWN ROTS, POLYPORES, SEXUALITY)." Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/187996.
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The inclusion of the species of polypores with rose-colored context in the genus Fomitopsis is proposed in this study. Temperature responses demonstrated that these fungi can be placed in three groups according to their optimum temperature for growth: (1) Fungi with an optimum at 25 C, Fomitopsis rosea; (2) Fungi with an optimum at 28 C, Fomitopsis feei, Fomitopsis lilacino-gilva, Fomitopsis cajanderi, and Fomitopsis carnea; (3) Fungi with an optimum at 30-34 C, Fomitopsis dochmius, F. cajanderi, and Fomitopsis cupreo-rosea. Decay tests showed that Fomitopsis feei and Fomitopsis lilacino-gilva reported only on hardwoods are also capable of decaying conifers "in vitro", causing weight losses up to 40% after 20 weeks. It was confirmed that all these fungi were brown rotters. An heterothallic, bipolar behavior was demonstrated for F. feei and agreed with the behavior previously reported for two other members on this complex, F. rosea and F. cajanderi. Due to the failure of the other isolates to fruit in culture, their sexual behavior could not be determined. Monokaryotic x monokaryotic pairings and monokaryotic x dikaryotic pairings showed homogenic or heterogenic incompatibility between members of the same species or different species. Vegetative incompatibility was found when pairing heterokaryotic dikaryons of different isolates of the same species which demonstrated genetic diversity in the populations. Dikaryotization did not occur when heterokaryotic dikaryons of F. lilacino-gilva, F. dochmius, F. carnea, and F. cupreo-rosea were paired with monokaryons of F. feei, F. cajanderi, or F. rosea which supported the concept of genetically different species.
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Punya, Juntira. "Polyketide synthase genes from the wood-decaying fungus Xylaria sp. BCC1067." Thesis, University of Westminster, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251721.
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Liu, Ran. "Voltammetric Study of Interaction of Copper and Model Fungal Secreted Ligands." Fogler Library, University of Maine, 2003. http://www.library.umaine.edu/theses/pdf/LiuR2003.pdf.
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Baumgart, Eligiusz Adam Iwo. "Parasitoids and beetles of decaying wood : the role of fungi and volatiles." Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520955.
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ADASKAVEG, JAMES ELLIOTT. "STUDIES OF GANODERMA LUCIDUM AND GANODERMA TSUGAE (DELIGNIFICATION, MATING SYSTEMS, ROOT ROT, CULTURAL MORPHOLOGY, TAXONOMY)." Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/188172.
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Ganoderma lucidum and G. tsugae are two members of the G. lucidum complex. The authenticity of the two wood-rotting species was demonstrated by comparative studies. Ganoderma lucidum is restricted to hardwoods. Its "smooth" walled basidiospores were characterized by narrow, numerous inter-wall pillars. Isolates of G. lucidum produced chlamydospores in culture and had an average growth of 7.8 mm/da at their optimum temperature range of 30-34 C. Ganoderma tsugae is restricted to conifers. Its basidiospores were "rough" walled and had broad inter-wall pillars. Isolates of G. tsugae did not produce chlamydospores in culture and had an average growth of 2.1 mm/da at the optimum temperature range of 20-25 C. Mating systems were determined for both species as heterothallic and tetrapolar. Interspecific matings of homokaryons were incompatible. Homokaryons of a European G. resinaceum isolate were interfertile with homokaryons from North American collections of G. lucidum. The ability of G. lucidum and G. tsugae to decay wood in vitro was studied using the following woods in agar block decay chambers: grape, oak, mesquite, white fir, and Douglas-fir. Grape wood lost the most weight while mesquite the least. G. lucidum isolates generally caused greater weight loss of all woods than did G. tsugae isolates. Both Ganoderma species caused simultaneous decay in all woods. However, chemical analyses of the decayed blocks indicated that selective delignification by both species also occurred in grape and white fir blocks but not in oak or Douglas-fir blocks. Scanning electron microscopy demonstrated various stages of selective delignification and simultaneous decay of all woods tested. Isolates of Ganoderma lucidum infected Dog Ridge variety grape plants, grown in the greenhouse, from below-ground wood block inoculations. Twenty-four plants were inoculated: one plant died and 4 other plants declined. After 24 months reisolations yielded only G. lucidum from the five declining plants, demonstrating pathogenicity. The fungus developed in the heartwood and, in later stages, invaded the sapwood. Infected plants developed water stress symptoms with leaves wilting, yellowing, and dying. Field grape plants inoculated with the fungus developed decay columns as large as 42 cm in 17 mons. Decay was limited to the heartwood; no foliar symptoms occurred.
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Jin, Lehong. "Detoxification of thujaplicins in living western redcedar (Thuja plicata Donn.) trees by microorganisms." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/27357.
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Thujaplicins are the major components in the steam-volatile fraction of western redcedar (Thuja plicata Donn.) (WRC) heartwood extractives. They are consided to be highly toxic to fungi and are chiefly responsible for WRC heartwood decay resistance. This study proves that this traditional concept of toxicity is not completely correct. Thujaplicins are toxic to common decay fungi isolated from decayed WRC wood in living trees or wood in service, such as Poria
albipelIucida Baxter. On the other hand, when a fungus such as Sporothrix sp. invades sound heartwood of living WRC, thujaplicins do not provide resistance but instead are altered by that fungus, so that their toxicity to decay fungi is destroyed.
Evidence obtained in this study indicates that the mechanism of thujaplicin toxicity to common decay fungi involves the reactive keto-enolic group. As example, thujaplicin toxicity disappears if this reactive group is blocked by laboratory methylation. In living trees detoxification by Sporothrix sp. is demonstrated to involve a process of oxidative dimerization and isomerization of the thujaplicins to a new lactone compound. This compound is proven to have no toxicity to decay fungi, such as Poria albipelIucida Baxter. The dimerization and isomerization destroy the reactivity of the keto-enolic group and thus thujaplicin toxicity.
Isolation, purification, and determination of the chemical structure of the new lactone compound produced from thujaplicins during Sporothrix sp. infection was carried out by chemical, chromatographic and spectroscopic methods. This naturally occurring compound has not been isolated previously and there are no previous reports in the literature about a compound with this structure. Following IUPAC rules, the compound is named as 3,3,4,7,7,8-hexamethyl-2,6-dioxa-1,5-anthracene-dione, and given the trivial name 'Thujin'.
Biological experiments carried out in this study clearly show that in living WRC trees, fungal attack involves a succession of microorganisms. Three early stage attacking fungi were consistantly isolated from discolored WRC heartwood. They are identified as Sporothrix sp. KirschsteinieIIa thujina (Peck) Pomerleau & Etheridge and Phialophora sp. Biological roles of these fungi are demonstrated based upon the results of wood block bioassays and chemical analysis of wood blocks treated with the three fungal isolates.Forestry, Faculty of
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Van, Heerden Andrea. "Assessment of wood degradation by Pycnoporus sanguineus when co-cultured with selected fungi." Thesis, Stellenbosch : Stellenbosch University, 2007. http://hdl.handle.net/10019.1/19884.
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Thesis (MSc)--University of Stellenbosch, 2007.ENGLISH ABSTRACT: It is commonly known that a diversity of fungi, including yeasts, may occur on plant surfaces. Similarly, on fallen trees an ecological succession of different fungal species is known to occur during wood degradation. Some of these fungi may be pioneer fungi contributing to the initial degradation process, while others may be yeasts associated with the fruiting bodies of macro-fungi which in turn are able to utilize the more recalcitrant polymers in wood. Previously, it was revealed that an increase occurs in the wood degradation rate of certain white-rot fungi when co-cultured with selected yeast species. A well known inhabitant of decomposing trees is the white rot fungus Pycnoporus sanguineus. It was found by some that this fungus is capable of selective delignification while growing on the wood of poplar trees, while other authors found a simultaneous delignification pattern on Eucalyptus grandis trees. In the latter case cellulose and lignin are degraded simultaneously. We were interested in how yeasts occurring on the surface of P. sanguineus fruiting bodies, and the pioneer fungus Aspergillus flavipes, impact on wood degradation by this white-rot fungus. Restriction Fragment Length Polymorphisms (RFLP) analyses were used to obtain an indication of the species composition of the culturable yeast community associated with fruiting bodies of P. sanguineus. The impact of the most dominant of these yeasts species, i.e. Pichia guilliermondii and Rhodotorula glutinis, as well as A. flavipes, on wood degradation by P. sanguineus was then determined by analyzing the major wood components after growth of co-cultures on hot water washed E. grandis wood chips. Co-cultures of P. sanguineus with the other fungi were prepared by inoculating the wood chips, contained in solid state bioreactors and supplemented with molasses and urea, with the an appropriate volume of fungal inoculum, resulting in an initial moisture content of 60%. After two weeks of incubation at 30°C with constant aeration, the chips were harvested. Standard protocol (TAPPI Standard Methods), commonly used by the paper and pulp industry, were then employed to determine the percentage cellulose, Klason Lignin, as well as polar and solvent-borne extractives in the chips. The resulting data were analyzed using box plots, as well as biplots. No degradation of Klason lignin was observed, while the percentage cellulose did decrease during fungal degradation. Taking into account the inherent shortcomings of the Klason Lignin determination, the results supported the findings of others that P. sanguineus shows a simultaneous delignification pattern while growing on E. grandis wood. In addition, it was found that the yeasts played no significant role in the degradation ability of P. sanguineus, while A. flavipes showed an antagonistic effect on P. sanguineus with respect to cellulose degradation. However, it was clear that the analytical methods used in this study were inadequate to accurately determine fungal degradation of wood. In addition, it was obvious that the methods used did not distinguish between fungal biomass and wood components. Nevertheless, the methods provided us with a fingerprint of each culture growing on E. grandis wood, allowing us to compare the chemical composition of the different cultures and the un-inoculated hot water washed wood chips. The question, therefore, arose whether the effect of a particular coculture, on the chemical composition of wood, differs between tree species. Consequently, chemical alterations in different tree species, induced by a P. sanguineus / A. flavipes co-culture, were investigated in the next part of the study. Wood chips originating from four tree species, i.e. Acacia mearnsii, Eucalyptus dunnii, E. grandis, and Eucalyptus macarthurii, were inoculated with this co-culture. The culture conditions and subsequent analyses of the wood components were the same as in the first part of the study. From the box- and biplots constructed from the resulting data, it was clear that the chemical composition of each tree species were altered in a different manner by the coculture. Lignin content showed an apparent increase in A. mearnsii, while E. dunnii showed a decrease in cellulose content. The results indicate that wood of different tree species are degraded in a different manner and this phenomenon should be taken into account in selecting fungi for biopulping.
AFRIKAANSE OPSOMMING: Dit is algemeen bekend dat 'n verskeidenheid fungi, insluitend giste, op plantoppervlaktes mag voorkom. Dit is ook bekend dat 'n ekologiese opeenvolging van verskillende fungusspesies tydens hout-afbraak op omgevalle bome voorkom. Van hierdie fungi mag pionierfungi wees wat bydra tot die aanvanklike afbraakproses, terwyl ander giste mag wees wat geassosieer word met die vrugliggame van makro-fungi, wat op hul beurt weer in staat is om die meer weerstandbiedende polimere in hout te benut. Dit is voorheen bekendgemaak dat daar 'n toename plaasvind in die tempo van houtafbraak deur sekere witvrot-fungi wanneer dit in ko-kulture met geselekteerde gisspesies voorkom. 'n Bekende bewoner van verrottende bome is die wit-vrotfungus Pycnoporus sanguineus. Dit is gevind dat hierdie fungus tot selektiewe delignifikasie in staat is terwyl dit op die hout van populierbome groei, terwyl ander outeurs 'n gelyktydige patroon van delignifisering op Eucalyptus grandis bome gevind het. In laasgenoemde geval is sellulose en lignien gelyktydig afgebreek. Ons was geïnteresseerd in die effek van giste op die oppervlak van vrugliggame van P. sanguineus, en die pionierfungus Aspergillus flavipes, op die houtafbraak deur hierdie wit-vrotfungus. Restriction Fragment Length Polymorphisms (RFLP) analises is gevolglik gebruik om 'n aanduiding te kry van die spesiesamestelling van die kweekbare gisgemeenskap wat met die vrugliggame van P. sanguineus geassosieer word. Die impak van die mees dominante van hierdie gisspesies, naamlik Pichia guilliermondii en Rhodotorula glutinis, asook A. flavipes, op houtafbraak deur P. sanguineus is voorts bepaal deur die analise van die belangrikste houtkomponente na die kweek van ko-kulture op E. grandis houtskyfies wat met warm water gewas is. Ko-kulture van P. sanguineus met die ander fungi is voorberei deur die houtskyfies in vaste fase bioreaktore, aangevul met melasse en ureum, te inokuleer met 'n toepaslike volume van die fungus inokulum om 'n aanvanklike voginhoud van 60% te verkry. Na twee weke se inkubasie by 30°C met konstante belugting is die skyfies ge-oes. Standaard protokol (TAPPI Standard Methods), algemeen deur die papier en pulpindustrie gebruik, is ingespan om die persentasie sellulose, Klason Lignien, asook polêre en oplosmiddel-gedraagde ekstrakte in die skyfies te bepaal. Die gevolglike data is geanaliseer deur gebruik te maak van box plots en biplots. Daar is geen afbraak van Klason Lignien bespeur nie, terwyl die persentasie sellulose wel toegeneem het tydens fungus degradasie. Met die inherente tekortkominge van die Klason Lignien bepaling inaggenome, het die resultate die bevindings ondersteun van andere wat getoon het dat P. sanguineus 'n gelyktydige delignifikasiepatroon openbaar terwyl dit op E. grandis hout groei. Daarby is dit gevind dat die giste geen beduidende rol in die afbraakvermoeë van P. sanguineus gespeel het nie, terwyl A. flavipes 'n antagonisiese effek ten opsigte van die sellulose degradering van P. sanguineus getoon het. Dit was egter duidelik dat die analitiese metodes wat in hierdie studie gebruik is, onvoldoende was om die degradering van hout akkuraat te bepaal. Daarby was dit duidelik dat die metodes nie tussen fungus biomassa en houtkomponente kon onderskei nie. Nogtans het die metodes 'n vingerafdruk verskaf van elke kultuur wat op E. grandis hout groei, wat ons toegelaat het om die chemiese samestelling van die verskillende kulture en die ongeïnokuleerde, met warm water gewasde houtskyfies te vergelyk. Die vraag het gevolglik ontstaan of die effek van 'n bepaalde ko-kultuur op die chemiese samestelling van hout van boomspesie tot boomspesie verskil. Gevolglik is die chemiese wisselinge in verskillende boomspesies, geïnduseer deur 'n P. sanguineus / A. flavipes ko-kultuur, in die volgende gedeelte van die studie ondersoek. Houtskyfies van vier boomspesies, naamlik Acacia mearnsii, Eucalyptus dunnii, E. grandis, en Eucalyptus macarthurii, is met hierdie ko-kultuur geïnokuleer. Die kultuurkondisies en daaropvolgende analises van die houtkomponente was dieselfde as in die eerste deel van die studie. Van die box- en biplots wat van die resultate getrek is, is dit duidelik dat die chemiese samestelling van elke boomspesie op 'n verskillende manier deur die ko-kulture verander is. Lignien-inhoud het ’n waarskynlike toename getoon in A. mearnsii, terwyl E. dunnii 'n afname in sellulose-inhoud getoon het. Die resultate toon dat hout van verskillende boomspesies op verskillende maniere afgebreek word en dat hierdie fenomeen in aanmerking geneem moet word wanneer fungi vir bioverpulping geselekteer word.
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Råberg, Ulrika. "Fungal degradation and discolouration of Scots pine : a molecular approach /." Uppsala : Swedish University of Agricultural Sciences, 2006. http://diss-epsilon.slu.se/archive/00001268/.
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Thesis (doctoral)--Swedish University of Agricultural Sciences, 2006.Thesis documentation sheet inserted. Errata sheet inserted. Appendix reprints four papers and manuscripts co-authored with others. Includes bibliographical references. Issued also electronically via World Wide Web in PDF format; online version lacks appendix.
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Qian, Yuhui. "The Chemical Mechanism of a Brown-Rot Decay Mimtic System and its Application in Paper Recycling Processes." Fogler Library, University of Maine, 2001. http://www.library.umaine.edu/theses/pdf/QianY2001.pdf.
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De, Koker T. H. (Theodorus Hermanus) 1965. "Genetic and enzymatic characterisation of wood degrading strains of Phanerochaete species." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51775.
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Thesis (PhD)--University of Stellenbosch, 2000.ENGLISH ABSTRACT: White rot fungi are of interest in the paper and pulp industry because of their removal of lignin from wood. In this study over 600 Basidiomycete fungi were isolated from indigenous forests as well as from commercial Eucalyptus spp. and Pinus spp. plantations in South Africa. One hundred isolates were identified to genus level. Biochemical tests were done to screen the fungal cultures for characteristics that are favourable for biopulping, e.g. low cellulase activity with concomitant high activity of ligninolytic enzymes. Various Phanerochaete isolates with potentially high ligninolytic activity were identified. Although Phanerochaete chrysosporium Burds. has previously been isolated from the indigenous forest at Knysna in South Africa, this study showed that P. chrysosporium was a natural coloniser of wood chip piles in South Africa, indicating potential for application in industry. A possible new species of Phanerochaete, viz. Phanerochaete pseudomagnoliae nom. provo (strain PP25) from decayed wood collected in Stellenbosch, South Africa, was described and illustrated. It differs from previously described Phanerochaete species in having smaller basidiospares, and in the formation of few chlamydospores on malt extract agar but more on xylose containing media. The potential of using internal transcribed spacer DNA sequences (ITS) to infer phylogenetic relationships among species of the genus Phanerochaete was investigated. Consensus phylogenetic trees could be presented, but the presence of ambiguous aligning sequences within the ITS made inferring of phylogenetic relationships within the whole genus difficult. Fifty-five South African strains of P. chrysosporium were screened for lignin peroxidase (liP), manganese peroxidase (MnP) and glyoxal oxidase (GLOX) enzymes. Manganese peroxidase activity was quantified on agar media. The liP and GLOX activities of 13 selected strains, including control strains and P. pseudomagnoliae (PP25), were also quantified on agar media. Differences in MnP and GLOX activities existed among the strains. Preliminary biochemical characterisation of strain PP25 indicated that the most important difference was the apparent unique regulation of ligninolytic enzymes. Under low nitrogen, liP activity of the selected strains showed no significant variation, whereas strain PP25 had significantly increased liP levels under high nitrogen conditions. Restriction fragment length polymorph isms of the lignin and manganese peroxidase gene DNA fragments showed variability among strains, whereas there was probably only allelic variation for the glox gene DNA fragments. Previous research has indicated xylose oxidation activity within P. chrysosporium. To investigate whether GLOX can oxidise xylose, a purified recombinant GLOX (rGLOX) from P. chrysosporium BKM-F-1767 Burds. was used in this study. This rGLOX oxidised D-xylose and D-glucose (D-xylose > D-glucose) to produce H202. Xylose was oxidised to xylono-1 ,4-lactone with a 1:1 stoichiometric relationship between H202 produced and xylose used. Xylono-1,4-lactone was converted non-enzymatically to xylonate. This suggested that the furanose form of xylose, rather than the pyranose form, is a substrate of GLOX. The production of H202 and the removal of inhibitory compounds by GLOX could enhance ligninolytic activity. . To conclude, unique strains of P. chrysosporium have been isolated from South Africa with potential biotechnological use in paper manufacturing. The relationship of P. pseudomagnoliae nom. provo to other Phanerochaete species was evaluated and light was shed on the possible role of GLOX in lignin degradation.
AFRIKAANSE OPSOMMING: Witvrot swamme is van belang vir die papier en pulp industrie omdat hulle lignin vanaf hout kan verwyder. Meer as 600 Sasidiomiseet fungi, afkomstig vanaf inheemse woude asook kommersiële Eucalyptus spp. en Pinus spp. plantasies, IS geïsoleer. Een honderd isolate is tot op genusvlak geïdentifiseer. Die isolate is biochemies vir eienskappe wat voordelig vir "bioverpulping" kon wees, bv. die gelyktydige produksie van lae sellulosemaar hoë ligninolitiese ensiemaktiwiteit, getoets. Verskeie isolate met potensieel hoë vlakke van ligninolitiese aktiwiteit is verkry. Alhoewel Phanerochaete chrysosporium Surds. vantevore in die Knysna inheemse woud in Suid-Afrika geïsoleer is, het hierdie studie gewys dat P. chrysosporium natuurlik op hope houtblokkies voorgekom, met moontlike toepasing in die industrie. Isolaat PP25, geisoleer vannaf verrottende hout te Stellenbosch, Suid Afrika, is as 'n potensieel nuwe spesie van die genus Phanerochaete beskryf en as Phanerochaete pseudomagnoliae nom. provo benoem. Hierdie isolaat verskil van ander Phanerochaete-spesies daarin dat dit kleiner basidiospore vorm en nie klamydospore op moutekstrakagar produseer nie, maar wel op media wat xilose bevat. Die potensiaal van intern getranskribeerde spasieerder ONS opeenvolging vir die aflei van filogenetiese verhoudings tussen spesies van die genus Phanerochaete is ondersoek. Konsensus filogenetiese bome kon bepaal word, maar die teenwoordigheid van varieerbare areas het die afleiding van filogenetiese verwantskappe vir die hele genus bemoeilik. Vyf-en-vyftig Suid-Afrikaanse isolate van P. chrysosporium is vir die teenwoordigheid van lignienperoksidase- (liP), mangaanperoksidase- (MnP) en glioksaaloksidase (GLOX)-aktiwiteit getoets. Vlakke van MnP-aktiwiteit is op agarplate gekwantifiseer. Vlakke van LiP- en GLOX-ensieme op agarplate is vir 13 geselekteerde isolate, insluitend kontroles en ras PP25, gekwantifiseer. Aktiwiteit van MnP en GLOX het statisties betekenisvol tussen isolate verskil. Lignienperoksidase-aktiwiteit onder lae stikstof toestande het nie statisties betekenisvol van mekaar verskil nie. Onder hoë stikstof toestande het isolaat PP25 wel verhoogde liP-aktiwiteit getoon. Restriksie fragment polimorfismes van die lignien- en mangaanperoxidase-gene het variasie getoon, terwyl waarskynlik slegs alleliese variasie vir die glox geen waargeneem IS. Rekombinante GLOX (GLOX vanaf P. chrysosporium BKM-F-1767) het xilose en glukose (D-xilose > D-glukose) geoksideer met meegaande produksie van H202. Xilose is na xilono-1,4-laktoon geoksideer met 'n 1:1 stoigiometrie tussen H202-produksie en xilose verbruik. Xilono-1,4-laktoon is nieensiematies na xilonaat omgeskakel. Bogenoemde resultaat dui aan dat die furanose vorm van xilose die werklike substraat vir GLOX is. Deur die meegaande produksie van H202 en die verwydering van inhiberende produkte word lignoliese aangehelp. Ten slote, unieke P. chrysosporium rasse met potensiële gebruik in papiervervaardiging is in Suid-Afrika geisoleer. Die genetiese diversiteit van 'n nuwe spesie, P. pseudomagnoliae, is bepaal en nuwe lig is op die potensiële rol van GLOX in lignienafbraak gewerp.
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Kirker, Grant Terral. "Effects of chlorothalonil (CTN) and butylated hydroxy-toluene (BHT) on microbial communities involved in the deterioration of wood using terminal restriction fragment length polymorphism (T-RFLP) analyses." Diss., Mississippi State : Mississippi State University, 2008. http://library.msstate.edu/etd/show.asp?etd=etd-04022008-155301.
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Fäldt, Jenny. "Volatile constituents in conifers and conifer related wood-decaying fungi. Biotic influences on monoterpene compositions in pines." Doctoral thesis, KTH, Chemistry, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3012.
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Lindhe, Anders. "Conservation through management : cut wood as substrate for saproxylic organisms /." Uppsala : Dept. of Entomology, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/s300.pdf.
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Bernal, Robin Rae. "Effects of Hydrologic Gradients on Woody Debris Breakdown and Macroinvertebrate Colonization in a Cumberland Plateau Watershed, Eastern Kentucky, U.S.A." TopSCHOLAR®, 2010. http://digitalcommons.wku.edu/theses/149.
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This research assessed the influence of hydrologic gradients on woody debris dynamics in a Cumberland Plateau watershed, eastern Kentucky, U.S.A. Although the breakdown of wood can be attributed to several different processes, including leaching, biological decay, fragmentation, and transport, the influence of differing flow regimes has been unstudied. The objectives of this study were to examine how stream channel type (temporary vs. perennial) affected wood processing dynamics (i.e., mass loss and macroinvertebrate colonization and standing stock patterns). Two questions were addressed: (1) do mass loss rates of wood differ across hydrological gradients in stream channels?, and (2) do macroinvertebrate colonization and standing stock patterns vary in relation to hydrologic gradients? Although within each channel type both dry mass and ash free dry mass loss followed a negative exponential model (p < 0.05), there wasn’t a significant between-channel difference in mass loss rates (p > 0.05). Breakdown rates (-k) ranged from 0.133 – 0.194year-1 for perennial streams compared to 0.103 – 0.170year-1 in the temporary streams. Collector-gathers comprised the greatest proportion of macroinvertebrates, accounting for 65.5% (temporary) and 59.3% (perennial) of all taxa colonizing wood bundles, followed by shredders (16.1%, 16.8%), predators (16.8%, 20.1%), (scrapers < 0.1% in both reaches) and filtering collectors (1.2%, 3.7%). Overall, there were no significant between-channel differences for total macroinvertebrate abundance, total macroinvertebrate biomass, and similarly for abundance and biomass of all functional groups. There was a trend, however, of decreasing density and biomass over time of collector-gathers and shredders on wood. Overall, hydrological gradients had no effects on short-term breakdown rates of woody debris or macroinvertebrate colonization patterns. Studies of wood breakdown have been shown to require long study periods (≥ 5 years), therefore, future studies of hydrological gradient may show differing results for woody debris breakdown.
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Gudrunsson, Mikael. "Forest fire drives long-term community changes of wood-decaying fungi in a boreal forest archipelago." Thesis, Mittuniversitetet, Avdelningen för naturvetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-24241.
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Conservation of wood-decaying fungi requires improved knowledge about the long-term effects of forest management; regarding habitat loss, fragmentation and fire suppression. To better understand such effects, I examined the influence of area, isolation, fire history and forest stand characteristics on communities of wood-decaying fungi. Species richness and composition were studied along a gradient of 22 forested islands varying in size (0.16 to 17.58 ha) and fire history (spanning 5000 years) in a boreal forest archipelago in northern Sweden. A total of 490 records of 41 polypore species were found in 33 circular plots, each 0.1 ha in size. Species richness and the number of red-listed species were analyzed using generalized linear models (GLMs), while species composition was examined using non-metric multidimensional scaling (NMDS) ordination. The species composition was clearly different between recent-fire (< 300 years since last fire) and old-fire (≥ 300 years since last fire) islands, mirroring the shift in tree species composition as pine-associated fungal species were replaced by spruce-associated fungal species. The volume of logs was the only variable influencing the species richness, although the diversity of logs showed a clear trend of also influencing species richness positively. The results demonstrate the importance of having both recent-fire and old-fire forests as landscape-level habitats and species pools, where fire naturally would constitute a key role for maintaining forest biodiversity in the boreal forest landscape. The results also stress the importance of dead wood for species richness at the individual forest stands.
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Atkinson, Toni June, and n/a. "Unexpected microfungal diversity : woody decay Lasiosphaeriaceae, Chaetosphaeriaceae and Helminthosphaeriaceae of New Zealand." University of Otago. Department of Botany, 2007. http://adt.otago.ac.nz./public/adt-NZDU20080207.093747.
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New Zealand�s lignicolous pyrenomycete flora has been little studied. The cosmopolitan Lasiosphaeriaceae, largest and least studied family in the Sordariales, has long been noted for its morphological diversity and the artificiality of its grouping. This first systematic study of lignicolous Lasiosphaeriaceae in New Zealand uses morphology and phylogenetics to elucidate relationships within the New Zealand mycota and facilitate comparisons with relatives worldwide. Collection areas spanned New Zealand�s 13 degrees of latitude and included a range of native forest types. The novel application of recently-available molecular biology techniques allowed sequencing from single pyrenomycete fruitbodies.
Two new genera and 15 new species or species complexes are proposed in total. A new genus is proposed within the Lasiosphaeriaceae to accommodate an interesting new collection. Seven new species are described in the known genera Lasiosphacria and Lasiosphaeris and the polyphyly of certain Lasiosphacria taxa is discussed. Five new taxa are described within the Chaetosphaeriaceae, including a pair with surprisingly unique morphology. All are currently placed within Chaetosphaeria, but comprise part of a recently recognised long-spored clade that is sister to that which includes the type genus. Within the Helminthosphaeriaceae one new genus is proposed to accommodate an unusual new collection; and a new species described within Hilberina, but its transference to a new genus predicted as knowledge of this recent family grows. Phylogenetic results support the separation of the Chaetosphaeriaceae and Helminthosphaeriaceae from the Lasiosphaeriaceae where many of these taxa were previously.
The traditional morphological character of ascospore shape is shown to have little use in the delimitation of genera. More recently emphasised characters such as peridial wall structure may have more value, however the fruitbody wall of some New Zealand taxa could not be more different from their phylogenetic relatives. New Zealand taxa are noted for their frequently unprecedented morphology and/or unique genetics in comparison with other known taxa, which are predominantly from the northern hemisphere. The high levels of morphological and genetic divergence among New Zealand taxa appear to reflect extensive microfungal endemism on these relatively isolated islands; but surveys of diversity in other parts of Gondwana are desperately needed.
A Key to New Zealand taxa within the Lasiosphaeriaceae, Helminthosphaeriaceae and long-spored Chaetosphaeriaceae is provided.
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Fairweather, Mary Lou 1958. "Cultural and other morphological studies of Inonotus andersonii." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276745.
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The nuclear behavior, vegetative incompatibility, and induction of basidiocarp formation and basidiospore germination of Inonotus andersonii was investigated. Safranin O-KOH and Hematoxylin stains were used to determine the number of nuclei in basidiospores, vegetative hyphae, and basidiocarp tissue. Both uni- and binucleate basidiospores were found in the tubes of basidiocarp tissue. The nuclei in the hyphal cells of presumptive heterokaryons typically numbered some multiple of two per cell which suggests that division is conjugate. Subhymenial hyphae and immature basidia were often uninucleate but tramal hyphae were multinucleate. Antagonistic hyphal interactions developed between different vegetative isolates on both 2% MEA and oakwood test blocks. Self-crosses were compatible. Basidiocarps formed in 12 wk on 2% MEA medium containing ground oakwood and wheat. Most attempts to induce spore germination failed. However, basidiospores obtained at the end of this study from actively sporulating basidiocarps germinated on 2% MEA.
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Klinka, Karel, Gordon J. Kayahara, and Christine Chourmouzis. "Comparison of soil acidification and intensity of podzolization beneath decaying wood versus non-woody forest floors in coastal BC." Forest Sciences Department, University of British Columbia, 2001. http://hdl.handle.net/2429/763.
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Forest managers concerned with maintaining soil productivity must consider the impacts of forestry practices upon the
features of a site. One critical feature is the amount and type of organic matter on a site, which may affect soil development.
This study addresses the question of whether CWD accumulations increase the intensity of podzolization, thus reducing
the long-term productivity of a site.
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Stahlhut, Dirk. "Decay Fungi from New Zealand Leaky Buildings: Isolation, Identification and Preservative Resistance." The University of Waikato, 2008. http://hdl.handle.net/10289/2637.
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Leaky buildings are those that show elevated moisture contents of the framing timber, which can subsequently lead to the establishment of fungal and bacterial decay. Prior to this study, the causative agents of the decay in these leaky buildings were unknown, though it was suspected to be one or more species of decay fungi. Therefore, the overall goal of this multi-disciplinary PhD thesis research was to determine the causative agents of decay in leaky buildings of New Zealand in an effort to develop solutions for both their remediation and future prevention. Use of molecular biology methodology and classical mycological techniques based on morphology enabled identification of decay fungi from framing timber and air samples of leaky New Zealand buildings and provided insight into relative importance based on isolation frequency. In most cases, fungi colonising Pinus radiata D. Don were isolated to produce pure cultures. Mycelia from these cultures on agar media were collected to extract DNA. To identify the fungi to the species level, polymerase chain reaction (PCR) with fungal specific DNA primer pairs were performed followed by DNA sequencing of the internal transcribed spacer (ITS) region. Identification was by BLAST (Basic Local Alignment Search Tool) search on sequences in known GenBanks. In total, 421 samples from leaky buildings were processed, predominately untreated P. radiata decayed framing timber and also fibre cement boards and building paper. From these, sixty-eight fungal identifications were made. The only taxa that were isolated with significant frequency were identified as 4 basidiomycete species, as follows, along with the number of times they were isolated from the 421 samples: • Gloeophyllum sepiarium (Wulf.: Fr.) Karst. 13x • Oligoporus placenta (Fries 1865) Gilb. In Ryv.1985 11x • Antrodia sinuosa (Fr.) Karst. 8x • Gloeophyllum trabeum (Fr.) Murr. 4x Although these species were identified repeatedly, in total they represent less than 10% of the total samples and, therefore, it is concluded that the leaky building decay samples represent high fungal biodiversity. An aerial spore study of internal air, wall cavity air and exterior air of leaky buildings was carried out using a Merck MAS-100 instrument which collects spores directly onto selective media plates. Viable fungal aerial spores were detected at every sampling location tested at the leaky buildings, by the criteria of culturing, with a highest mean of 3714 colony-forming units (CFU) per cubic metre found in the cavities of water-damaged walls. This aerial spore study in conjunction with isolation from decayed wood samples from the same leaky buildings enabled identification of G. sepiarium and A. sinuosa at the same test site. The use of carboxymethylcellulose medium further demonstrated the presence of potential cellulose-degrading fungi within and around the location. Overall, the combination of direct sampling of timber and air sampling proved useful for detection of fungal species variability at a multi-unit building. Four decay fungi isolated from New Zealand leaky buildings and two standard control decay fungi (Coniophora puteana and Serpula lacrymans) were submitted to laboratory wood block testing to determine the effectiveness of currently used wood framing preservatives under laboratory conditions before and after a standard leaching regime. P. radiata blocks were treated with water based boron copper azole and solvent based IPBC propiconazole plus tebuconazole (1:1) preservatives and exposed to the basidiomycetes for 12 weeks. Mass loss for the fungal decay-infected samples was recorded of up to 55% for preservative-treated samples, up to 62% mass loss for leached samples and up to 58% mass loss for un-preservative treated samples. Additionally, well defined dosage responses and approximate toxic thresholds were obtained for all preservatives tested. Results suggested that the minimum IPBC retention specified by Hazard Class 1.2 of NZS3640:2003 (0.025% m/m) is on the low side, and demonstrated after the 2 week leaching regime complete loss of efficacy of boron at 0.4% m/m boric acid equivalent (BAE). This PhD research gave a first overview of fungi occurring in New Zealand leaky buildings, and it demonstrated the following key aspects of wood preservation: 1. The isolated test fungus Antrodia sinuosa was more difficult to control with propiconazole plus tebuconazole at retention 0.007% m/m than the known tolerant fungus Oligoporus placenta; 2. Boron at Hazard Class 1.2 retention of 0.4% m/m BAE was not toxic to Oligoporus placenta; 3. Serpula lacrymans exhibited tolerance to the highest retention of 0.06 %m/m tebuconazole plus propiconazole; and 4. Gloeophyllum species appeared susceptible to all wood preservatives. In order to correlate fungal colonisation and wood decay, colonised wood blocks were studied using light microscopy (LM) and field- emission scanning electron microscopy (FE-SEM). Microscopic observations of P. radiata wood blocks following a standard wood decay test of twelve weeks of fungal colonisation by Serpula lacrymans, Antrodia sinuosa, Oligoporus placenta and Gloeophyllum sepiarium revealed that the two microscopic techniques employed were complementary by allowing features such as pit membranes, chlamydospores or S3/S2 compound middle lamella interface to be photographed in greater detail, allowing for more precise analyses and interpretation of key findings, as follows: 1. Brown rot fungi directly target their apical growth towards degraded pit apetures; 2. Reliance on light microscopy and observed birefringence as a tool to record changes in cell wall crystallinity associated with brown rot decay alone could be misleading; 3. Presence of fine (≤ 1 m) to wide (≥ 3.5 m) bore-hole and hyphal size ranges, and nearly unchanged cell wall thickness of all wood/test fungal combinations, confirmed active decay at moderate to late stages; 4. Some ray parenchyma cells for Antrodia sinuosa, Oligoporus placenta and Gloeophyllum sepiarium colonised blocks were intact throughout late stages of decay, outlining that they were not preferentially degraded early in the brown rot decay process, and 5. Presence of bore-holes, clamp and medallion clamp formation and resting spores (chlamydospores and arthrospores) are fungal specific, can aid in their differentiation and identification, and should be recorded during wood decay studies, as especially resting spores are an important factor when planning remediation strategies. In summary, this PhD thesis research provided the first comprehensive investigation into the biodiversity of fungi from leaky New Zealand buildings, identified the dominant species and presented details about their micromorphology and their decay patterns. It also demonstrated substantial differences in efficacy of preservative formulations currently (December 2008) approved for framing treatments in New Zealand and possible deficiencies where framing may be subjected to severe leaching. This study also provided the first comparative analyses of viable fungal aerial spores between leaky wall cavities and the surrounding air environment. Subsequently, this research added to the knowledge of the decay fungal species diversity in and around New Zealand leaky buildings, outlined their capabilities to degrade treated and un-treated P. radiata framing timber and illustrated the efficacy of New Zealand approved wood preservatives for their potential as remedial treatment and future prevention.
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Perold, Maurits. "The effect of sodium lauryl sulphate on blue stain, mould growth and surface properties of SA pine." Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/2003.
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Thesis (MScFor (Forest and Wood Science))--University of Stellenbosch, 2006.Producing high quality end products, rather than focusing on volume production, is slowly but surely becoming the main driving force in the wood processing industry of South Africa. Drying defects such as surface checks and discolouration by yellow stain and kiln brown stain are major factors in softwood timber downgrades when selecting furniture grade timber. Previous efforts to control these defects have focused on schedule adaptation, but as the industry is still mainly concerned with volume production, and because of the varying lumber price, longer schedules to control these drying defects have not yet been that attractive for the larger sawmills. In ongoing research in this laboratory, a dip treatment of freshly sawn softwood boards in an aqueous solution containing a surfactant called sodium lauryl sulphate (SLS) was used to try to influence the mechanism involved in the development of these stains. Further, complementary research is reported in this study. Firstly, the possibility of using SLS solutions to control surface mould development and bluestain was investigated. Results showed that SLS did control the development of blue stain and mould growth in open-stacked boards for up to three weeks, using concentrations as low as 0.1%, and up to two weeks in closed-stacked timber when using concentrations of 0.2%. Secondly, it was investigated whether SLS treatment would have a detrimental effect on downstream product quality; in particular, kiln dried boards and glued components for furniture manufacturing. Since SLS influenced fluid water flow during kiln drying, the treatment could have exacerbated the occurrence of surface checking due to altered moisture distribution profiles. Results of this investigation showed that the SLS treatment did not result in increased surface checking. Thirdly, as furniture quality timber treated with SLS would be glued, (and also finished with surface coatings), it was further considered important to determine if SLS treatment influenced adhesion properties of wood surfaces. Based on shear test results, it was established that SLS did not influence the adhesion properties of wood when glued with two most commonly used glues in the furniture industry i.e. polyvinyl acetate (PVAc) and urea formaldehyde (UF).
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Magnusson, Magnus. "Red-listed wood-decaying fungi in natural and managed forests : A comparative study on forest structures and species composition in boreal forests." Thesis, Umeå University, Ecology and Environmental Science, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-22805.
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Murphy, John F. "The ecology and population biology of two litter decomposing basidiomycetes." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-06302009-040233/.
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Bucci, Robert Joseph. "Molecular based identification of wood decay fungi from two field sites in Mississippi." Master's thesis, Mississippi State : Mississippi State University, 2008. http://library.msstate.edu/etd/show.asp?etd=etd-06182008-141603.
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Ronaritivichai, Anjaruwee 1962. "CULTURAL AND OTHER STUDIES ON FUNGI THAT DECAY ARIZONA CYPRESS." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/275483.
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Yang, Xiaotong, and 楊曉彤. "The anticancer mechanisms of polysaccharide peptide (PSP) derived fromthe Chinese medicinal fungus coriolus versicolor." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31246229.
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Mohebby, Behbood. "Biological attack of acetylated wood." Doctoral thesis, Göttingen : Cuvillier, 2003. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=010518063&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Arantes, Valdeir. "Caracterização de compostos de baixa massa molar redutores de ferro produzidos por fungos e mediação da reação de fenton para degradação de polissacarídeos e lignina." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/97/97132/tde-20082013-170539/.
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Os fungos de decomposição branca e parda produzem enzimas para degradar os componentes da madeira, os primeiros produzem enzimas hidrolíticas e oxidativas enquanto os outros produzem principalmente enzimas hidrolíticas. A degradação de polissacarídeos e lignina por fungos de decomposição parda e branca seletiva, respectivamente, não ocorre na região imediata à hifa, e, também, não pode ser explicada unicamente por ação enzimática devido a impermeabilidade das mesmas na parede celular. Neste trabalho estudou-se o sistema degradativo não enzimático envolvendo compostos de baixa massa molar (CBMM) redutores de ferro em fungos degradadores de madeira. O fungo de decomposição parda, Wolfiporia cocos e o de decomposição branca seletiva, Perenniporia medulla-panis foram cultivados em diferentes concentrações de ferro, e a atividade redutora de Fe3+ micelial e a extracelular, assim como a produção de quelantes específicos de ferro, como derivados de ácido hidroxâmico e de catecol, foram induzidas em condição de deficiência de ferro. Os géis de SDS-PAGE dos extratos fúngicos mostraram várias proteínas negativamente reguladas por ferro em P. medulla-panis e W. cocos, principalmente para proteínas entre 10 - 30 kDa. Quando os fungos foram cultivados em diferentes fontes de carbono simples com e sem suplementação de celulose microcristalina e deficiência de ferro, produziram CBMM redutores de Fe3+, os quais tiveram a produção estimulada nos meios com celulose. Análises de eletroforese capilar dos compostos quelantes de metal extraídos dos meios que proporcionaram a maior atividade redutora (Lornitina/ celulose para P. medulla-panis e glicose/celulose para W. cocos) na presença e ausência de ferro, confirmaram que, principalmente P. medulla-panis produz compostos extracelulares que são regulados por ferro. Os CBMM purificados das frações < 5 kDa apresentaram atividade redutora de Fe3+ em pH 2,0 mesmo quando ácido oxálico foi adicionado na concentração 20 vezes maior que a concentração de Fe3+. Em pH 4,5, a atividade redutora foi detectada até uma concentração de ácido oxálico 10 vezes superior a de Fe3+. Em ambos os casos a atividade redutora foi observada quando Fe3+ estava presente na forma livre ou complexada como Fe(oxalato)+. Dentre os vários CBMM produzidos por P. medulla-panis e W. cocos aqueles com atividade redutora foram o ácido 4-hidroxi-fenilacético, 1,2-dihidroxi-3-metil-benzeno, 1,2,3-trihidroxi-benzeno e o ácido 4- hidroxi-cinâmico para W. cocos, e para P. medulla-panis os principais foram 1,2-dihidroxibenzeno e 1,2,3-trihidroxi-benzeno. Além desses compostos, ambos os fungos produziram peptídeos de baixa massa molar com atividade redutora. Os CBMM redutores de Fe3+ de P. medulla-panis (Pmp) e de W. cocos (Wc) foram utilizados na ausência e presença de Fe3+ e H2O2 (reação de Fenton mediada) para oxidar polissacarídeos e lignina in vitro. Verificou-se que os maiores níveis de oxidação foram obtidos nas reações de Fenton mediadas (Wc-Fe3+/H2O2 e Pmp-Fe3+/H2O2). A degradação da celulose por estes sistemas foi caracterizada por uma rápida e extensiva despolimerização, seguida de significativa oxidação. Análises dos monômeros de lignina liberados de conífera tratada e não tratada após 13C-TMAH termoquimólise indicaram oxidação da lignina pelos sistemas Wc-Fe3+/H2O2 e Pmp- Fe3+/H2O2, principalmente por desmetoxilação e/ou desmetilação. A ação sinérgica entre os CBMM redutores de Fe3+ e as enzimas ligninolíticas ficou evidenciada para os fungos de decomposição branca Lentinula edodes, P. medulla-panis e Trametes versicolor através da oxidação do corante Azure B.Brown and white rot fungi produce enzymes to degrade wood. The former produce hydrolytic and oxidative enzymes while the latter produce mainly hydrolytic enzymes. The degradation of polysaccharides and lignin by brown and white-rot fungi, respectively, do not occur next to the fungal hyphae and cannot be explained only by the enzymatic action due to the small pore size of sound wood. In this work, it was studied a non-enzymatic degradative system involving low molecular weight compounds (LMWC) with Fe3+-reducing activity in wood decay fungi. The brown rot fungus Wolfiporia cocos and the selective white rot Perenniporia medulla-panis were grown under varying concentration of iron. The micelial and extracellular Fe3+-reducing activity as well as the production of specific iron chelators (catechol and hydroxamate derivatives) were induced under iron starvation. SDS-PAGE gels of cellular proteins showed several proteins negatively iron-regulated in P. medulla-panis and in W. cocos, especially for proteins of 10 - 30 kDa. When the fungi were grown with different simple carbon source with and without microcrystalline cellulose supplementation and under iron restriction, they produced LMWC with Fe3+-reducing activity, which production was stimulated in the presence of cellulose. Capillary electrophoresis analyses of metal chelating compounds extracted from the growth media that promoted the highest Fe3+-reducing activity (L-ornithine/cellulose for P. medulla-panis and glucose/cellulose for W. cocos) in the presence and absence of iron, confirmed that, especially P. medulla-panis produces extracellular compounds that are iron-regulated. LMWC purified from these media showed Fe3+-reducing activity at pH 2.0 even when oxalic acid was added up to 20 fold the iron concentration. At pH 4.5, the Fe3+-reducing activity was detected at an oxalic acid concentration up to 10 fold the iron concentration. In both cases the LMWC were capable of reducing Fe3+ only when it was in its free form or complexed with oxalate to form Fe3+-monooxalate complex (Fe(C2O4)+). Among the several LMWC produced by P. medulla-panis and W. cocos those with Fe3+-reducing capability were 4-hydroxy-phenylacetic acid, 1,2- dihydroxy-methyl-benzene, 1,2,3-trihydroxy-benzene and 4-hydroxy-cinnamic acid to W. cocos and 1,2-dihydroxy-benzene, and 1,2,3-tri-hydroxy-benzene to P. medulla-panis. Both fungi also produce low molecular weight peptides with Fe3+-reducing capability. The purified LMWC with Fe3+-reducing activity from P. medulla-panis (Pmp) and from W. cocos (Wc) were utilized in the presence and absence of Fe3+ and H2O2 (mediated Fenton reaction) to oxidize polysaccharides and lignin in vitro. The highest oxidation levels were obtained with mediated Fenton reactions (Wc-Fe3+/H2O2 e Pmp-Fe3+/H2O2). Cellulose degradation by these systems was characterized by a rapid and extensive depolymerization followed by significant oxidation. Analyses of the lignin monomers released from treated and untreated softwood after 13C-TMAH thermochemolysis indicated lignin oxidation by the Wc-Fe3+/H2O2 and Pmp-Fe3+/H2O2 systems, mainly by demethoxylation and/or demethylation. The synergistic action between LMWC with Fe3+-reducing activity and the ligninolytic enzymes was evidenced to the white rot fungi Lentinula edodes, P. medulla-panis and Trametes versicolor with Azure B oxidation assays.
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Křivánková, Soňa. "Průzkum a hodnocení stavu dřevěné konstrukce." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226973.
Full textAbstract:
This work is focused on compilation of general diagnostic methods used for diagnostic of wooden structures specifically listed wooden roof truss of church st. Bartholomew in Ivan. The main impulse of diagnosis was extensive damage and attack of truss and effort on rehabilitation and construction of the entire building of the church with an emphasis on preserving historical values. Diagnosis of truss was based on the research used sense and instrumental methods. In the first step, identify all dimensions of the individual elements of the structure was determined, the type truss system was intended. Follow-up survey was focused on determining the extent and causes of damage. In design of the rehabilitation process emphasis is placed on structural rehabilitation provided by follow-up processes, such as preventive chemical protection.
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Brazolin, Sérgio. "Biodeterioração, anatomia do lenho e análise de risco de queda de árvores de tipuana, Tipuana tipu (Benth.) O. Kuntze, nos passeios públicos da cidade de São Paulo, SP." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-20042010-092326/.
Full textAbstract:
Os objetivos do presente trabalho foram: avaliar o processo de biodeterioração do lenho das árvores de tipuana na cidade de São Paulo e relacionar as alterações da sua estrutura anatômica e propriedades físico-mecânicas com o seu risco de queda. Nos passeios públicos de regiões selecionadas da cidade, 1109 árvores de tipuana foram caracterizadas quanto às condições de entorno, estado geral, variáveis dendrométricas, biodeterioração externa e interna e o risco de queda, estimado com modelo de cálculo estrutural desenvolvido pelo IPT. A biodeterioração e os mecanismos de resistência das árvores foram avaliados ao nível macroscópico e microscópico. As alterações nas propriedades do lenho de tipuana foram analisadas por densitometria de raios X e pelos ensaios físico-mecânicos (densidade de massa aparente; resistência à flexão) e aplicado o método de elementos finitos para análise da distribuição de tensões no lenho. As árvores de tipuana de elevada idade não apresentaram sinais de declínio, embora com estado geral considerado como crítico, pelo plantio em locais indequados, manejo inapropriado e/ou ocorrência de injúrias. O lenho foi deteriorado por fungos apodrecedores, cupins-subterrâneos e brocas-de-madeira, sendo os fungos e cupins os principais organismos xilófagos, afetando a região do cerne; a associção entre os fungos, os cupins, as variáveis dendrométricas e o risco de queda foram estatisticamente significantes ao nível de 5 %. O cupim-subterrâneo Coptotermes gestroi ocorreu em elevados níveis de infestação nas árvores, sendo considerado, no entanto, como um organismo-praga secundário, fortemente associado com lenho previamente apodrecido por Ganoderma sp.. Os fungos apodrecedores ocorrentes foram classificados como de podridão branca e mole, sendo a primeira mais comum no cerne das árvores. Como mecanismo de resistência à biodeterioração observou-se a compartimentalização do lenho, caracterizada pelo acúmulo de extrativos nas células. Os fungos xilófagos causaram reduções significativas na densidade de massa aparente, tensão de ruptura à flexão estática e módulo de elasticidade em estágios incipiente e intenso de apodrecimento do lenho. Ruptura do tronco e o risco de queda das árvores de tipuana relacionaram-se, principalmente, com a intensidade da deterioração do lenho e com a sua dendrometria. A alteração da distribuição das tensões no lenho foi analisada em relação ao estágio, tamanho e localização da deterioração no tronco das árvores de tipuana.The objectives of the present work were to evaluate the process of biodeterioration in the wood of tipuana trees in the city of São Paulo and to relate the alterations in the anatomical structures and physical and mechanical properties with there falling risk. In the sidewalks of selected regions of the city, 1109 trees were characterized taking into consideration aspects as surroundings, general conditions, dendrometric variables, external and internal biodeterioration and falling risk estimated by using a structural model developed by IPT. The biodeterioration and the resistance mechanisms of the trees were evaluated at a macro and microscopic levels. The alterations on the wood properties were analysed by X-rays densitometry and by performing physical and mechanical tests (specific gravity; bending resistance); the tension distribution in the wood was analyze by finite-elements method. The old aged trees encountered, did not show any sign of decline, eventhough, the general aspect of their surroundings was critical by the inadequate places they were planted; inappropriate management and/or occurrence of injuries. The trees had their trunks deteriorated by xylophagous organisms, mainly fungi and subterranean-termites, and some wood borer beetle too, which affected the heartwood. The association between the presence of the first two organinsms, the dendrometric variables and the risk of falling, was statistically significant at the 5% level. The infestation of the trees by the subterranean-termite Coptotermes gestroi was at high levels, however, it was considered as a secundary plague-organism, because its attack was strongly associated with the previously decayed heartwood by Ganoderma sp.. The decaying fungi observed were classified as white rot and soft rot, being the white rot more common in the heartwood of the trees. As a resistance mechanism of the trees against biodeterioration, it was observed the compartimentalization of the wood characterized by the accumulation of extractives in the cells. Decaying fungi caused significant reductions in the following wood properties: specific gravity, rupture strength to bending and modulus of elasticity either in incipient or intense decay. Trees trunk rupture and falling risk were associated mainly to biodeterioration intensity and dendrometric variables. The alteration of tension distribution in the wood was analyzed in relation to the stage, size and position of the deterioration in the wood of the trees.
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Bartlová, Jana. "Návrh rekonstrukce dřevěných konstrukcí stávajícího objektu." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227155.
Full textAbstract:
The content of this work was to carry out construction-technical survey of timber structures of the existing building in order to design an appropriate procedure for their reconstruction. The survey showed construction in an unsatisfactory to disrepair, so further work also includes the static calculation of new structures proposed instead of the current. Timber structure in the building has form of staircase, roof and ceiling construction. Newly designed the following types of stairs and roof trusses from which the lower belts are used as ceiling beams. The new proposal also includes possible roofing, roofing options, developed one of them. The work also includes drawings, bill of materials and cost estimate staircase structure and truss. Specialization in the field of civil engineering is represented by drawings of the new truss and passport (view of current state) whole object on parcel ST.74 / 1, land Tišnov (okr.Brno-venkov), the content of which was the basis for this work.
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Duncan, Shona M. "Fungal diversity and cellulytic activity in the historic huts, Ross Island, Antarctica /." 2007. http://adt.waikato.ac.nz/public/adt-uow20070501.175007/index.html.
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Mankowski, Mark Edward. "Effects of wood species and prior fungal exposure on the feeding habits of the dampwood termite Zootermopsis angusticollis." Thesis, 1992. http://hdl.handle.net/1957/37194.
Full textAbstract:
The effects of natural preconditioning (source wood), wood species, and previous
exposure of wood to two types of fungi on the feeding rates and protozoa survival in the
Pacific dampwood termite Zootermopsis angusticollis (Isoptera: Termospidae) were
examined under laboratory conditions. Termites were exposed to four wood species that
had been treated previously with a non-wood decay fungus or a wood decay fungus for
various lengths of time, or were untreated. Termite feeding was measured in forced
feeding and choice feeding tests, after which two types of gut protozoa (Trichomitopsis
spp. and Trichonympha spp.) were counted.
Wood species and previous fungal exposure both affected consumption rates and
protozoa numbers in Z. angusticollis. The results indicated that pre-conditioning did not
affect the amount of wood consumed or protozoa numbers in forced feeding tests, but
sometimes affected protozoa numbers in choice feeding tests. Exposure of various conifer
woods to an early colonizing white rot fungus, Stereum sanguinolentum, affected how
much wood of a particular species was consumed by dampwood termites in both forced
and choice feeding tests. Exposure of these woods to a non-wood decay fungus,
Trichoderma viride, had little effect on wood consumption but did affect the numbers of
one type of gut protozoan, Trichoniitopsis, in choice testing.Graduation date: 1993
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Qian, Yuhui. "The chemical mechanism of a brown-rot decay mimetic system and its application in paper recycling processes /." 2001. http://www.library.umaine.edu/theses/pdf/QianY2001.pdf.
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Barker, Jason Scot. "The effects of moisture content and initial heterotrophic colonization on the decomposition of coarse woody debris." Thesis, 2003. http://hdl.handle.net/1957/32268.
Full textAbstract:
Previous research on coarse woody debris (CWD) indicated that moisture
content and initial heterotrophic colonization of decaying wood can affect
the decomposition process. Six heterotrophic treatments were created to
simulate the effects of physical penetration of the bark and wood and the
transmission of ascomycetes versus basidiomycetes into CWD. In 1995,
360 Douglas-fir (Pseudotsuga menziesii) were randomly placed at five
replicate sites in old-growth stands. Each site had 6 heterotrophic (HET) x
2 moisture combinations (TENT). One set of logs representing the
treatment combinations was used for sampling respiration and another set
was used to measure volume affected by insect gallery excavations and
fungal rot and to determine decay rates. Respiration was sampled three
times during the summer of 2001. The results indicated that the HET
treatments were no longer affecting respiration rates. Analysis of the
average of the three sampling periods revealed no TENT effect but
examinations of the individual sampling dates suggests that tented logs
might have higher respiration rates than non-tented logs as summer
progresses. In the aggregate, the TENT treatment reduced moisture
content from 45% to 36%, a 20 percent reduction in moisture levels. The
HET and the TENT treatments did not affect decay rates. The mean
density change for the logs was -0.072 g/cm�� �� 0.03 and the mean decay
constant was 0.026 �� 0.011. The TENT treatment did affect heterotrophic
activity. The mean volume of wood borer excavation and extent of brown
rot was higher in the tented logs (256 cm��) than in the non-tented logs
(59.9 cm��). There was also a statistically significant interaction between
the HET and TENT treatments. The largest differences in volume affected
by wood borers and fungal rot were found in treatments that injected
ascomycetes into the experimental logs. In sum, there was limited
evidence that the differences in moisture content caused by the TENT
treatment affected the decomposition process but the HET treatments
appear to not be directly influencing decomposition after six years. The
findings suggest differences in the initial community composition of
heterotrophs have a decreasing impact on the decomposition process as it
progresses.Graduation date: 2004
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Rhatigan, Ronald G. "Toxicity of methyl bromide to fungi inhabiting Dahurian larch wood /." 1996. http://hdl.handle.net/1957/11078.
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Ismail, Shenaz. "The effect of chemical preservation of Pinus patula wood chips during outside chip storage." Thesis, 2015. http://hdl.handle.net/10539/16907.
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Hawkins, Robert E. "����C-CP MAS NMR study of decomposition of five coniferous woody roots from Oregon." Thesis, 2002. http://hdl.handle.net/1957/32056.
Full textAbstract:
Using ����C cross polarization magic angle spinning nuclear magnetic resonance
techniques on 5 species of dead trees from the northwest (western hemlock, Douglas fir,
Sitka spruce, lodgepole pine and ponderosa pine) I tracked the lignin and cellulose content
over a 22 to 36 year period in order to determine the effects of decay fungi, if any, that is
attacking certain species of tree. I had samples from the wood of the roots, the bark on the
roots and, in some cases, the resin core of the roots. The Department of Forest Science at
Oregon State University has studied this problem by using wet chemical analysis, and
direct visual observation. Mark Harmon and Hua Chen of the Department of Forest
Science believe that white rot occurred most frequently in the lodgepole pine and
ponderosa pine and brown rot was more frequent in the Douglas-fir and Sitka spruce.
Western hemlock seemed to have both brown and white rots active.
The Douglas fir bark sample showed definite decomposition consistent with white rot
during the first 10 years. The ponderosa pine sap showed decomposition consistent with
white rot in the 10 to 22 year period. Sitka Spruce showed some decomposition consistent
with white rot in the bark from 7 to 33 years, and the western hemlock showed some
decomposition consistent with white rot in the sap in the first 10 years.
The decompositions consistent with brown rot were much easier to see in this study.
Virtually all the sap and bark samples showed decomposition consistent with brown rot at
some point. The Douglas fir was the only species, other than lodgepole pine, not to show
any decomposition consistent with brown rot in the bark of the tree, only decomposition
consistent with white rot. The Douglas fir did show a decay consistent with brown rot in
the sap for the first ten years. Ponderosa pine showed evidence of decay that brown rot
would cause for the first 10 years in the sap and the bark. The Sitka spruce species
analysis showed brown rot type decay in the bark for the first 7 years and in the sap for the
entire time studied of 33 years. The lodgepole pine was the only species to not show any
brown rot type decay in the sap or bark for the entire 22 year period studied. The western
hemlock was distinct by not showing any definitive brown rot type decay for the first 10
years, but showed massive decay consistent with brown rot in both sap and bark during the
following 26 years studied.
I used an 8 Tesla magnet and the MAS frequency was at 5 kHz. The recycle time was
1.5 seconds and the contact time was 1 ms. I generally took about 10,000 acquisitions per
sample, which added up to about 4 hours total acquisition time per sample.
Presence of these rots shows that certain species are more susceptible than others, and
also shows that local environmental conditions can contribute to rot susceptibility.Graduation date: 2003
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Zrůstová, Petra. "Ekologie hub, asociovaných s tlejícím dřevem v ekosystémech přirozených lesů." Master's thesis, 2014. http://www.nusl.cz/ntk/nusl-332178.
Full textAbstract:
Dead wood plays an important role in forest ecosystems in the context of C dynamics, nutrient cycling, forest regeneration and biodiversity. Decaying wood sustains biodiversity by providing habitats and energy for fungi, bacteria, invertebrates, and many other organisms. Dead wood is resistant to decomposition and its decay is driven mainly by filamentous fungi. Community structure of wood- inhabiting fungi changes during decomposition, but the relationship between substrate quality and decomposer community is still poorly understood. This work studied fungal community composition with respect to tree species, stage of decay, volume and physico-chemical properties (such as pH, carbon and nitrogen content) of dead wood. Fungi were identified using next generation sequencing approaches - 454-pyrosequencing and Illumina MiSeq sequencing. Tree species, volume of dead wood (branches x logs) and stage of decay were the main variables affecting fungal community composition. Higher enzyme activities and content of fungal biomass indicate faster colonization of small branches than tree trunks by fungi. Fungal community composition, wood chemical properties and enzyme activities changed during decomposition. Both content of nitrogen and fungal biomass increased during decomposition. Enzyme activites peaked...
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Štercová, Lucie. "Význam rozkladu dřeva houbami v ekosystémech přirozeného lesa." Master's thesis, 2017. http://www.nusl.cz/ntk/nusl-368456.
Full textAbstract:
The decomposition of organic substrates represents an important part of the global carbon cycle and affects its global change through CO2 release. In temperate forests, deadwood represents a large carbon stock, its amount and decomposition is crucial for ecosystem biodiversity and functioning. The fungi are omnipresent powerful decayers in all terrestrial ecosystems. Their ability to decompose all deadwood compounds, mainly lignocellulose, is highly important. Without fungi, the wood decompositions and the release of withheld nutrients back to nutrient cycles couldn't be performed. While many studies were concerned with the estimation of decomposition rates of deadwood, still deeper knowledge about microbial decomposition processes and the diversity of saproxylic species and their interaction is needed. The fungi are still underrepresented in dead wood studies. This study had two main objectives. First was to describe the fungal community on downed deadwood of Fagus sylvatica and Abies alba in natural forest of Salajka in the Czech Republic, to reflect the substrate changes during the different decay stages, and to link the enzyme activities to fungal community composition and their described ecophysiologies. Second aim was to describe the fungal communities on standing and downed dead logs of...
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POUSKA, Václav. "The role of wood decay fungi in the dynamics of a mountain spruce forest." Doctoral thesis, 2012. http://www.nusl.cz/ntk/nusl-110456.
Full textAbstract:
This thesis is focused on environmental preferences of wood-decaying fungi and their relationships with forest structure and development. Relationships of fungi to properties of wood and forest stands were studied on the basis of field observations in Central-European mountain spruce forests. Plot-based approach was used to reveal a general pattern in the diversity of fungi within a single forest stand and between different stands. The analysis of stand structure provided a background for plot-based approach. Substrate-based approach was used to study single species preferences and their communities. In addition, the influence of wood properties (including fungi and their rots) on the regeneration of spruce on logs was studied.