Dissertations / Theses: 'Saprophytes'

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Liggitt, Joanne. "Studies on the chemical control of Fusarium ear blight of winter wheat (Triticum aestivum L.)." Thesis, Open University, 1997. http://oro.open.ac.uk/54549/.

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The fungicides prochloraz and tebuconazole (at concentrations of2 J.lg ml-I ) were shown to reduce the mycelial growth of Fusarium culmorum, F. avenaceum, F. poae, F. gramineanlm and Microdochium nivale in vitro by over 90 % compared to the untreated control. In addition, chlorothalonil inhibited spore germination of all species and pyrimethanil reduced the mycelial growth of M nivale by over 60 % at 2 J.lg ml-I , although it was ineffective against the other species. In the glasshouse, prochloraz and tebuconazole were moderately effective in reducing the severity of fusarium ear blight (FEB) caused by F. culmorum and M nivale. The fungicides gave less effective control of FEB in the field. There was a significant relationship between the incidence and severity of FEB in 1995 but there was no significant relationship between ear blight and yield in either 1995 or 1996. It was proposed that the interactions between saprophytic microflora and ear blight pathogens may account for the poor performance of fungicides against FEB in vivo. Glasshouse and laboratory studies showed that Alternaria alternata, Botrytis cinerea and Cladosporium herbarum reduced the severity of FEB caused by F. culmorum and this antagonism was attributable to both volatile and non-volatile antibiotic production. The saprophytic species showed inherent variability in their sensitivity to the fungicides tested in vitro and in the glasshouse. It was shown that certain fungicides (e.g. pyrimethanil) which reduced mycelial growth of the saprophytic species in vitro allowed the pathogen to grow by reducing the antagonism of the microflora species against the pathogen. This may not be true for all fungicides in practice. It was also proposed that the inefficacy of fungicides to control FEB was due to a failure of the fungicide to reach the site of infection. It was shown, using a fluorescent tracer that retention 11 of spray was influenced by cultivar, time of application and fungicide. The amount of tracer retained was significantly correlated with the number of extruded anthers of wheat. When radio-labelled prochloraz was applied to the ears of wheat, the prochloraz was retained predominantly on the outer glumes, with very small amounts being retained by the florets and rachis. There was no movement of prochloraz between tissues and the half-life of the active ingredient was 48 hours. This work illustrates the efficacy of fungicides against Fusarium spp. and Microdochium nivale in vitro, under glasshouse conditions and in the field, and provides some evidence to explain their poor performance. It is proposed that future work should investigate environmental and biological factors which contribute to ear blight epidemics, in order that a forecasting system for fungicide application can be devised. Also, studies of fungicide activity against antagonistic ear microflora species and studies of fungicide retention and penetration may help to optimise fungicide application to control this disease.

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Mathieu, Yann. "Diversité écologique et fonctionnelle des champignons décomposeurs du bois : l'influence du substrat de la communauté à l'enzyme." Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0255/document.

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Les champignons saprophytes sont les acteurs principaux du recyclage de la matière organique morte au sein des écosystèmes forestiers. Ces microorganismes possèdent la capacité unique de dégrader la totalité des polymères constitutifs du bois. L'analyse de la structuration des communautés durant les stades initiaux de la colonisation du bois par séquençage à haut débit a révélé que celui-ci influence la distribution et la dynamique des communautés qui lui sont associées. A l'échelle de l'organisme, les différents groupes écologiques de champignons décomposeurs du bois possèdent des systèmes de dégradation extracellulaires reflétant cette complexité chimique. Le séquençage du génome d'un grand nombre de ces organismes a permis l'identification de superfamilles d'enzymes impliquées dans les mécanismes de résistance et de détoxication des composés toxiques exogènes. Parmi elles, la superfamille des glutathion transférases présente une extension de classes spécifiques au sein des champignons décomposeurs du bois. La détermination des propriétés biochimiques et structurales d'une isoforme, issue d'une de ces classes spécifique (les Etherase-like), présente chez Phanerochaete chrysosporium a révélé des caractéristiques particulières. Cette enzyme possède un mode de dimérisation atypique ainsi que la capacité à séquestrer des composés phénoliques toxiques via une propriété ligandine unique. La comparaison des propriétés de plusieurs isoformes de cette classe d'enzymes appartenant aux champignons C. cinereus et P. chrysosporium a démontré que celle-ci exhibe une grande versatilité intra- et interspécifique, de leurs activités enzymatiques et de leur propriété ligandine
Saprophytic fungi are key players of dead organic matter recycling in forest ecosystems. These microorganisms possess the unique ability to degrade the integrality of wood constitutive polymers by secretion of complex oxydative and hydrolytic enzymatic systems. Communities structuration analysis during the initial stages of wood colonisation by high throughput sequencing revealed that the latter beyond being a source of nutrients, influences the distribution and dynamic of communities by its broad chemical variability. At the organism level, the different ecological groups of wood decomposing fungi possess extracellular degradation systems reflecting this chemical complexity. Genome sequencing of these organisms allowed the identification of enzymes superfamilies involved in resistance and detoxification mechanisms towards exogenous toxic compounds. Among them, the glutathione transferases superfamily exhibit extension of specific classes in wood decaying basidiomycetes. Biochemical and structural properties determination of one isoform belonging to one of these specific classes (the Etherase-like), found in Phanerochaete chrysosporium revealed unusual characteristics. This enzyme possesses an atypical dimerization mode as well as the ability to sequestrate toxic phenolic compounds resulting from wood degradation through a unique ligandin property. Properties comparison of several isoforms from this class belonging to C. cinereus and P.chrysosporium demonstrated a huge intra- and interspecific versatility of their enzymatics activities and ligandin property in response to environmental constraints arising from the great chemical heterogeneity of wood composition

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Deroy, Aurélie. "Évolution et adaptation des champignons saprophytes : les systèmes impliqués dans la dégradation du bois chez Trametes versicolor." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0169/document.

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Le bois représente une des ressources en polymères les plus abondantes de l’écosystème terrestre. Les champignons dégradant la matière lignocellulosique jouent un rôle important dans le cycle du carbone. Ils présentent un fort intérêt au niveau biotechnologique en particulier pour la production d’enzymes. Parmi les champignons saprophytes, ceux de la classe des Agaricomycota sont particulièrement intéressants puisqu’ils possèdent la capacité de dégrader les différents composés du bois : cellulose, hémicelloloses et lignine. De plus, ces champignons ont développé un système de détoxication impliquant des enzymes telles que les glutathion transférases (GST). Celles-ci sont impliquées dans la dégradation de composés potentiellement toxiques générés lors de la dégradation du bois mais également la dégradation de xénobiotiques. L’étude des systèmes extracellulaires et intracellulaires de Trametes versicolor impliqués dans les processus de décomposition du bois, décrite dans ce manuscrit, avait pour objectif d’identifier les facteurs moléculaires impliqués dans l’adaptation des champignons à leur environnement. Les approches pluridiciplinaires mises en œuvre lors de cette thèse ont permis d’identifier une variabilité phénotypique intraspécifique chez une dizaine de souches de T. versicolor, cette variabilité semblant être liée à la nature de l’essence ligneuse d’origine de ces souches. De plus, les travaux réalisés sur les GSTs apparteant aux classes oméga et GHR ont contribué à améliorer nos connaissances sur l’implication de cette famille multigénique dans l’adaptation des champignons xylophages à leur mode de vie
Wood is one of the most abundant polymer resources of the Earth’s ecosystem. Wood decaying fungi play an important role in the carbon cycle. They have a strong interest in biotechnology level in particular for the production of enzymes. Among the saprophytic fungi, those of the class of agaricomycota are particularly studied since they possess the ability to degrade varous compounds from wood : cellulose, hemicelluloses dand lignin. In addition, these fungi have developed a detoxification system involving enzymes such as glutathione transferases (GST). These latter are involved in degradation of wood but also in the degradation of xenobiotics. In this manuscript, the study of extracellular and intracellular system from Trametes versicolor, involved in wood decay process is described, the main goal being to identify the molecular factors involved in adaptation of the to their environment. Multidisciplinary approaches used in this PhD led to identification of an intraspecific phenotypic variability among ten strains of T. versicolor, this variability appearing to be related to the tree species where these strains have been isolated. Moreover, the work done on GSTs belonging to GHR and omega classes have improved our knowledge of the involvement of this gene family in adaptating the wood decayers to thrit lifestyle

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Thuillier, Anne. "Diversité fonctionelle des Glutation Transférases fongiques : caractérisation des classes Ure2p et GTT2 de Phanerochaete chrysosporium." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0219/document.

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Phanerochaete chrysosporium est un champignon forestier faisant partie des organismes saprophytes capables de recycler la matière organique morte. Grâce à l'excrétion de nombreuses enzymes de dégradation, en particulier des lignine peroxydases, il est capable de décomposer la matière végétale dont la lignine, un polymère complexe de composés phénoliques très résistant. L'élimination de la lignine permet la libération des autres composants du bois tels que la cellulose et l'hémicellulose qui peuvent être utilisés dans l'industrie papetière ou pour la production de bioéthanol de deuxième génération. La structure des intermédiaires et produits de dégradation de la lignine est souvent proche de celle denombreux polluants, d'où l'intérêt biotechnologique de P. chrysosporium dans les processus de bioremédiation. Cependant, les systèmes de dégradation engendrent des composés plus ou moins toxiques pour le champignon et contre lesquels il doit faire face. C'est pourquoi il possède un système de détoxication impliquant des enzymes telles que les cytochrome P450 monooxygénases ou encore les glutathion transférases (GST). Les Ure2p forment une classe de GST étendue chez Phanerochaete et d'autres basidiomycètes saprophytes. Leur étude par des approches phylogénétiques, biochimiques, structurales et transcriptomiques a permis de mieux comprendre les mécanismes d'évolution que peut subir une classe d'enzymes potentiellement soumises à une forte pression de sélection
Phanerochaete chrysosporium is a forest fungus being part of saprophytic organisms able to recycle dead organic matter. Thanks to the excretion of numerous wood decaying enzymes, and especially lignin peroxidases, this fungus is able to break down plant material including lignin, a complex polymer of phenolic compounds. Lignin removal allows the release of other wood components such as cellulose and hemicellulose, which can be further used in paper industry or to produce second generation bioethanol. The structure of intermediates and products from lignin decomposition is close to that of numerous pollutants making P. chrysosporium biotechnologically interesting for bioremediation purposes. Moreover, the fungus has to deal with more or less toxic compounds created by degradation mechanisms. It thus presents a detoxification pathway involving enzymes including cytochrome P450 monooxygenases and glutathione transferases (GST). Ure2p enzymes belong to an extended GST class in Phanerochaete genus as well as in other saprophytic basidiomycetes. Their study based on phylogenetic, biochemical, structural and transcriptomic approaches provides a better understanding of evolution mechanisms of a class of enzymes potentially subject to strong selection selection pressure

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Dang, Ha X., Barry Pryor, Tobin Peever, and Christopher B. Lawrence. "The Alternaria genomes database: a comprehensive resource for a fungal genus comprised of saprophytes, plant pathogens, and allergenic species." BioMed Central Ltd, 2015. http://hdl.handle.net/10150/610283.

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BACKGROUND: Alternaria is considered one of the most common saprophytic fungal genera on the planet. It is comprised of many species that exhibit a necrotrophic phytopathogenic lifestyle. Several species are clinically associated with allergic respiratory disorders although rarely found to cause invasive infections in humans. Finally, Alternaria spp. are among the most well known producers of diverse fungal secondary metabolites, especially toxins. DESCRIPTION: We have recently sequenced and annotated the genomes of 25 Alternaria spp. including but not limited to many necrotrophic plant pathogens such as A. brassicicola (a pathogen of Brassicaceous crops like cabbage and canola) and A. solani (a major pathogen of Solanaceous plants like potato and tomato), and several saprophytes that cause allergy in human such as A. alternata isolates. These genomes were annotated and compared. Multiple genetic differences were found in the context of plant and human pathogenicity, notably the pro-inflammatory potential of A. alternata. The Alternaria genomes database was built to provide a public platform to access the whole genome sequences, genome annotations, and comparative genomics data of these species. Genome annotation and comparison were performed using a pipeline that integrated multiple computational and comparative genomics tools. Alternaria genome sequences together with their annotation and comparison data were ported to Ensembl database schemas using a self-developed tool (EnsImport). Collectively, data are currently hosted using a customized installation of the Ensembl genome browser platform. CONCLUSION: Recent efforts in fungal genome sequencing have facilitated the studies of the molecular basis of fungal pathogenicity as a whole system. The Alternaria genomes database provides a comprehensive resource of genomics and comparative data of an important saprophytic and plant/human pathogenic fungal genus. The database will be updated regularly with new genomes when they become available. The Alternaria genomes database is freely available for non-profit use at http://alternaria.vbi.vt.edu.

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Savoie, Jean-Michel. "Organisation des communautés fongiques saprophytes et adaptations à l'environnement biochimique : cas de la décomposition de la litière d'aiguilles d'Abies alba Mill." Lyon 1, 1989. http://www.theses.fr/1989LYO10148.

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Valette, Nicolas. "Caractérisation fonctionnelle de petites protéines sécrétées chez les champignons lignolytiques." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0324/document.

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Durant ces dernières décennies, les systèmes enzymatiques de dégradation du bois sécrétés par les champignons ont fait l’objet de nombreuses études aboutissant à la caractérisation fonctionnelle et biochimique des enzymes extracellulaires majeures agissant directement sur le polymère. Cependant, les systèmes annexes associés au processus de dégradation n’ont à l’heure actuelle été que peu étudiés. En particulier, les systèmes de détoxication et de réponses des champignons au stress généré par le processus de dégradation ainsi que les mécanismes lui permettant de croître dans cet environnement hostile sont encore peu connus. Ce stress est majoritairement dû à la présence de radicaux et d’extractibles. Les extractibles sont des molécules issues du métabolisme secondaire de l’arbre qui sont synthétisés pour augmenter la durabilité du bois face aux attaques biotiques et abiotiques. Une analyse transcriptomique réalisée au laboratoire a mis en évidence la surexpression de gènes codant des petites protéines sécrétées (SSP) chez Phanerochaete chrysosporium lors d’une culture en présence d’extractibles de chêne. La fonction de ce type de protéines chez les champignons lignolytiques est inconnue. Mon projet de thèse a porté sur la caractérisation d’une de ces SSP (SSP1). Les résultats obtenus ont révélé des propriétés biochimiques atypiques pour cette protéine qui est capable de former une structure fibrillaire, notamment grâce à la présence d’un domaine C-terminal riche en alanine et glycine. De plus, nous avons pu montrer que cette protéine présentait une activité β-glucuronidase in vitro, qui est dépendante de son état d’oligomérisation. Une approche physiologique a également été abordée grâce à l’obtention de mutants knock-out de SSP de Podospora anserina. La caractérisation de ces mutants a montré un défaut de croissance en condition de stress oxydant et en présence de molécules perturbant l’intégrité de la paroi cellulaire. Enfin, une analyse in silico des orthologues de SSP1 a montré la présence de ce gène dans les génomes d’organismes saprophytes, ectomycorhiziens ou pathogènes suggérant un rôle indirect de cette protéine dans les processus de dégradation du bois, probablement en lien avec la gestion du stress associé
During the last decades, the enzymatic systems involved in wood degradation have been intensively studied in fungi. This has led to functional and biochemical characterization of the main extracellular enzymes that are involved in the process. However, other systems associated to the degradation mechanisms have been poorly studied. In particular, the detoxification and stress response pathways allowing the fungus to grow in and resist the toxic conditions that are associated to the degradative process are still unknown. This stress is mostly due to the presence of radicals and extractives. Extractives are putative toxic compounds produced as secondary metabolites in tree to enhance wood durability against biotic and abiotic attacks. A transcriptomic analysis performed in the laboratory highlighted the up-regulation of genes coding for small secreted proteins (SSP) in Phanerochaete chrysosporium in presence of oak extractives. The functions of these SSP are unknown in lignolytic fungi. My PhD project was focused on the characterization of one of these SSP (namely SSP1) of P. chrysosporium. The biochemical data revealed atypical features for SSP1. Indeed, it is able to form fibrilar structure, thanks to an alanine-rich and glycine-rich C-terminal domain. Moreover, we have shown that this protein exhibits β-glucuronidase activity in vitro which is dependent on its oligomerization state. Physiological data were obtained thanks to the obtention of SSP knock-out mutants in Podospora anserina. These mutants have growth defect in oxidizing stress condition and in presence of cell wall-disruptive compounds. Finally, the in silico analysis of SSP1 orthologues revealed the presence of this gene in genomes of saprophytic, ectomycorrhizal or pathogenic fungi, suggesting an indirect role of this protein in wood degradation processes, probably linked to the associated stress

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Silva, Raquel Maria Morgadinho de Abreu e. "Micobiota cutânea de coelho (Oryctolagus cuniculus) e cobaio (Cavia porcellus) de companhia." Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2019. http://hdl.handle.net/10400.5/18024.

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Dissertação de Mestrado Integrado em Medicina Veterinária
O coelho e o cobaio são cada vez mais frequentes como animais de companhia. Entre as infeções zoonóticas que podem existir nestas espécies destaca-se a dermatofitose, e o coelho e cobaio já foram referenciados como possíveis portadores assintomáticos de dermatófitos. Os objetivos deste estudo incluíram a caracterização da micobiota cutânea destas espécies; determinação da frequência de fungos dermatófitos em coelhos e cobaios com e sem lesões cutâneas, nas áreas de Barcelona e Lisboa; avaliação da relação entre os resultados das culturas micológicas e diversas variáveis relacionadas com a caracterização e maneio dos animais; comparação entre dois meios de cultura utilizados para diagnóstico micológico, o meio Sabouraud Chloramphenicol Agar (SCA) e o meio Dermatophyte Test Medium (DTM); por último, comparação entre dois métodos de colheita de amostra para análise micológica – arrancamento de pelos e escovagem do animal (método de Mackenzie). Foram recolhidas 118 amostras de pelo e pele de coelhos e cobaios através de arrancamento de pelos e recolha de escamas em lesões (quando existentes) ou ao longo do corpo do animal e 51 amostras através de escovagem. As amostras foram semeadas nos meios referidos, incubadas e observadas diariamente. Por fim, as espécies fúngicas foram identificadas por observação da morfologia macro e microscópica das colónias. Foi realizado um questionário aos tutores em Lisboa para recolher informação relativa ao maneio dos animais. Não foram identificados fungos dermatófitos a partir das amostras; no entanto, foram isolados maioritariamente fungos saprófitas, semelhantes aos encontrados na pele e pelo de outros animais, nomeadamente Aspergillus, Penicillium e Scopulariopsis, muito frequentes no ambiente, tendo sido já reportados como responsáveis por infeções micóticas em humanos e animais. A análise estatística permitiu evidenciar que as variáveis “espécie”, “idade” e “medicação” são significativas em relação à variação da variável “positividade na cultura micológica”, enquanto a “idade”, “acesso ao exterior” e “medicação” são significativas em relação à variação da variável “número de espécies fúngicas isoladas” a partir das amostras. Concluiu-se que existe maior probabilidade de obtenção de uma cultura positiva e de um maior número de espécies fúngicas por amostra se estas forem semeadas em meio SCA do que em DTM; no entanto, apesar de o DTM ser um meio desenvolvido com o objetivo de permitir um diagnóstico fácil de dermatófitos pela ocorrência de alteração da cor do meio, neste estudo houve outras espécies fúngicas que também promoveram esta alteração. Por fim, concluiu-se que com a aplicação do método de Mackenzie há maior probabilidade de se isolar mais espécies fúngicas do que através do método de arrancamento, mas não foi possível concluir se havia animais portadores de dermatófitos apenas diagnosticados após sementeira das amostras obtidas pelo método de Mackenzie pois não se obtiveram resultados positivos. Assim, propõe-se a realização de um estudo comparativo entre estes métodos de colheita baseado num maior número de amostras, incluindo resultados positivos a dermatófitos.
ABSTRACT - Nowadays, rabbits and guinea pigs are frequently adopted as companion animals. Among the zoonotic infections that can affect these species dermatophytosis is the most frequent, and rabbits and guinea pigs have already been referred as possible asymptomatic carriers of dermatophytes. The goals of this study included the characterization of the cutaneous mycobiota of these species; determination of the frequency of dermatophytes in rabbits and guinea pigs from Barcelona and Lisbon, including animals with and without cutaneous lesions; evaluation of the relationship between the results from mycological cultures and several variables related to the characterization and management of these animals; comparison between two culture media used for mycological diagnosis, Sabouraud Chloramphenicol Agar (SCA) and Dermatophyte Test Medium (DTM); finally, comparison between two methods for sample collection for mycological analysis – hair pulling and animal brushing (Mackenzie’s technique). Samples included 118 hair and skin samples, collected from rabbits and guinea pigs by pulling hairs surounding lesions and collecting scales (if present) or along the body of the animal and also 51 hair samples collected using the Mackenzie’s technique. Samples were inoculated in the referred culture media, incubated and observed daily. Finally, fungal species were identified by observing the macro and microscopic morphology of the colonies. A questionnaire was provided to the tutors of animals in Lisbon, to collect information on animal husbandry. No dermatophyte fungi were identified from any of the samples under study; however, saprophytic fungi, similar to those found on the skin and hair of other animals, such as Aspergillus, Penicillium and Scopulariopsis, were mainly isolated; these fungi have already been reported as responsible for mycotic infections in humans and animals. The statistical analysis showed that the variables "species", "age" and "medication" are significant in the explanation of the variation of the "positivity in the mycological culture", while "age", "outdoor access" and "medication" are significant in the explanation of the variation of the "number of isolated fungal species" from the samples. It was also concluded that there was a higher probability of obtaining a positive culture and a larger number of fungal species per sample if they were inoculated in SCA medium than in DTM; however, although DTM is a medium developed with the goal of allowing an early diagnosis of dermatophytes by observing the changes in the color of the medium, in this study there were other fungal species that also promoted this change. Finally, it was possible to conclude that Mackenzie’s technique allows the isolation of a higher number of fungal species than the pulling method; however, it was not possible to conclude if this technique is associated with a more frequent dermatophytosis diagnostic since no positive results were obtained. Thus, a comparative study between these collection methods based on a larger number of samples is proposed, in order to include positive results for dermatophytes.
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Bottollier-Curtet, Marion. "Conséquences des invasions végétales sur le fonctionnement des écosystèmes riverains fluviaux." Phd thesis, Université Paul Sabatier - Toulouse III, 2010. http://tel.archives-ouvertes.fr/tel-00743158.

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Dans le contexte des invasions, l'objectif de ce travail est d'évaluer dans quelle mesure l'origine des espèces végétales conditionne le fonctionnement d'un écosystème en situation de dominance. Cinq paires d'espèces autochtones dominantes (Agrostis stolonifera, Rubus caesius, Populus nigra, Urtica dioica et Salix alba) et introduites envahissantes (Paspalum distichum, Fallopia japonica, Buddleja davidii, Impatiens glandulifera et Acer negundo) ont été comparées en milieu riverain pour les processus de production primaire et de dégradation des litières. Ces études ont été complétées par une analyse détaillée des conséquences de l'invasion des ripisylves par A. negundo. Nos résultats montrent que si les espèces introduites envahissantes peuvent être plus efficaces dans la réalisation de certains processus écologiques, l'absence de coévolution entre les espèces introduites et les organismes des milieux récepteurs n'a pas d'implication systématique pour le fonctionnement des écosystèmes.

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Muthumeenakshi, Sreenivasaprasad. "Molecular taxonomy of the genus Trichoderma." Thesis, Queen's University Belfast, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264087.

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Kyritsis, Polyvios. "Epidemiology and pathogenesis of mycelial soil borne Rhizoctonia solani AG 3 on potatoes (Solanum tuberosum)." Thesis, University of Aberdeen, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288350.

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This thesis describes aspect of the epidemiology and pathogenicity of the soil-borne phase of Rhizoctonia solani AG-3 (Kuhn) fungus on potatoes and its competitive saprophytic colonisation ability in the soil. Under controlled environmental conditions, stem canker incidence and severity increased with increasing levels of soil-borne inoculum but plateaued after ¼ inoculum level (i.e 1 Petri dish of R. solani AG-3 per kg soil). Up to the 1/20 inoculum stem canker occurred at a low level. A significant increase occurred at 1/10 and 1/8 inoculum levels. A similar pattern was observed for the competitive saprophytic colonisation ability of the fungus. The fungus was attracted more by seed tubers than by stems and the incidence of black scurf was higher than stem canker at all inoculum levels tested. Sclerotia developed on seed tubers even at low inoculum levels. Favourable soil conditions for infection on stems and seed tubers were 10^oC and soil moisture content of 40% water holding capacity. Optimum moisture content for saprophytism was between 20-50% water holding capacity, although optimum levels of the individual soils tested varied. Pot and laboratory experiments indicated that conditions for development of R. solani were more conducive in heavy than in light textured soils. When fine sand was added in increasing quantities to a sandy clay loam soil, the disease initiated by the fungus was steadily reduced with an increase in sand content. Potato cultivars differed in their susceptibility to R. solani at early stages of growth but none of the cultivars tested showed complete resistance to the disease. Depth of planting had no significant effect of Rhizoctonia stem and seed tuber infection.

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Mirza, Babur S. "Saprophytic growth and fate of Frankia strains in soil /." View online, 2009. http://ecommons.txstate.edu/dissertations/AAI3384734/.

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Creaser, M. L. "Spatio-temporal dynamics of saprophytic populations of Rhizoctonia solani Kühn." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.598143.

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Rhizoctonia solani is a vigorous soilborne, fungal plant pathogen that is responsible for substantial losses to many agriculturally important crops. The pathogen's destructive nature and wide host range has promoted considerable research into its taxonomy, pathology, and ecology, in an effort to develop effective methods of disease control. The population dynamics of R. solani have received considerable attention in regard to plant infection and disease development. However, few studies have focused on the saprophytic population dynamics of this organism that has been described as a saprophyte in which parasitism is largely incidental to saprophytism. The objectives of the present study were to investigate the effects of abiotic and biotic factors, principally incubation temperature and the presence of the fungal antagonist Trichoderma viride, on the temporal and spatio-temporal dynamics of saprophytic populations of two isolates of R. solani under controlled environment conditions. The saprophytic population dynamics of R. solani were investigated using a combination of fungal quantification techniques and inoculum placement studies. After investigation of the Enzyme Linked Immunosorbent Assay, ELISA, as a tool for quantification of R. solani, in comparison with ATP and chitin assays, ELISA was selected as the most appropriate assay for an investigation of population dynamics. Inoculum placement studies were used to evaluate the effects of T. viride on the growth and ability of R. solani to colonise a substrate from varying distances. The progress of the parasitic phase of R. solani is determined by, among other factors, initial inoculum density, propagule size and isolate. This study has shown that saprophytic populations of R. solani exhibit cycles of fungal activity that are affected by interactions between temperature with initial inoculum components and isolate. These factors determine the magnitude, duration and timing of cycles of saprophytic activity, as measured by ELISA. In no instance was the antagonist, T. viride, able to eliminate R. solani within a microcosm. Placement studies, in which propagules of T. viride were placed at varying distances from propagules of R. solani, concluded that the controlling effects of T. viride were localised and limited due to the slow growth of the fungus from its initial substrate in comparison with the growth of R. solani.

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14

com, kathrynmccarren@hotmail, and Kathryn McCarren. "Saprophytic ability and the contribution of chlamydospores and oospores to the survival of Phytophthora cinnamomi." Murdoch University, 2006. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20060807.92625.

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Phytophthora cinnamomi has been recognised as a key threatening process to Australias biodiversity by the Commonwealths Environment Protection and Biodiversity Conservation Act 1999. Despite over 80 years of extensive research, its exact mode of survival is still poorly understood. It is widely accepted that thin- and thick-walled chlamydospores are the main survival propagules while oospores are assumed to play no role in the survival of the pathogen in the Australian environment, yet evidence is limited. The saprophytic ability of the pathogen is still unresolved despite the important role this could play in the ability of the pathogen to survive in the absence of susceptible hosts. This thesis aimed to investigate chlamydospores, oospores and the saprophytic ability of P. cinnamomi to determine their contribution to survival. Phytophthora cinnamomi did not show saprophytic ability in non-sterile soils. The production of thick-walled chlamydospores and selfed oospores of P. cinnamomi in vitro was documented. Thick-walled chlamydospores were sporadically formed under sterile and non-sterile conditions in vitro but exact conditions for stimulating their formation could not be determined. The formation of thick-walled chlamydospores emerging from mycelium of similar wall thickness was observed, challenging the current knowledge of chlamydospore formation. Selfed oospores were abundant in vitro on modified Ribeiros minimal medium in one isolate. Three other isolates tested also produced oospores but not in large numbers. Although the selfed oospores did not germinate on a range of media, at least 16 % were found to be viable using Thiozolyl Blue Tetrazolium Bromide staining and staining of the nuclei with 4´, 6-diamidino-2-phenylindole.2HCl (DAPI). This indicated the potential of selfed oospores as survival structures and their ability to exist dormantly. The ability of phosphite to kill chlamydospores and selfed oospores was studied in vitro. Results challenged the efficacy of this chemical and revealed the necessity for further study of its effect on survival propagules of P. cinnamomi in the natural environment. Phosphite was shown to induce dormancy in thin-walled chlamydospores if present during their formation in vitro. Interestingly, dormancy was only induced by phosphite in isolates previously reported as sensitive to phosphite and not those reported as tolerant. Chlamydospores were produced uniformly across the radius of the colony on control modified Ribeiros minimal medium but on medium containing phosphite (40 or 100 µg ml-1), chlamydospore production was initially inhibited before being stimulated during the log phase of growth. This corresponded to a point in the colony morphology where mycelial density changed from tightly packed mycelium to sparse on medium containing phosphite. This change in morphology did not occur when the pathogen was grown on liquid media refreshed every four days, and chlamydospores were evenly distributed across the radius of these colonies. This trend was not observed in selfed oospores produced in the presence of phosphite. Selfed oospore production was found to be inhibited by phosphite at the same concentrations that stimulated chlamydospore production. Isolates of P. cinnamomi were transformed using a protoplast/ polyethylene glycol method to contain the Green Fluorescent Protein and geneticin resistance genes to aid in future studies on survival properties of the organism. Although time constraints meant the stability of the transgene could not be determined, it was effective in differentiating propagules of the transformed P. cinnamomi from spores of other microrganisms in a non-sterile environment. Two different sized chlamydospores (approximately 30 µm diameter and < 20 µm diameter) were observed in preliminary trials of transformed P. cinnamomi inoculated lupin roots floated in non-sterile soil extracts and these were easily distinguished from microbial propagules of other species. The growth and pathogenicity was reduced in two putative transformants and their ability to fluoresce declined over ten subcultures but they still remained resistant to geneticin. This study has improved our knowledge on the survival abilities of P. cinnamomi in vitro and has provided a useful tool for studying these abilities under more natural glasshouse conditions. Important implications of phosphite as a control have been raised.

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15

Diss, Loïc. "Transporteurs fongiques de manganèse : diversité et analyse fonctionnelle chez le champignon saprophyte Phanerochaete chrysosporium." Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0189/document.

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P. chrysosporium est un champignon saprophyte capable de dégrader de nombreux xénobiotiques, ce qui le rend particulièrement intéressant pour des applications en bioremédiation. Plusieurs publications mettent en avant l'importance de la maîtrise de l'homéostasie métallique dans la production de certaines enzymes lignolytiques. La présence de manganèse est en effet nécessaire à la production des manganèses peroxydases, alors qu'à l'inverse une carence permettra la production de lignines peroxydases. Cependant, la caractérisation de transporteurs impliqués dans le contrôle de l'homéostasie métallique n'a fait l'objet de recherches poussées que chez le champignon modèle S. cerevisiae. L'analyse des transporteurs putatifs de manganèse de 26 espèces fongiques représentant 20 ordres fongiques a permis de constituer un répertoire de 281 transporteurs de manganèse. L'analyse phylogénétique a permis de mettre en évidence que des processus de duplication, mais également de délétion, avaient eu lieu en particulier chez S. cerevisiae. Cependant ce dernier ne possède pas de transporteurs de manganèse appartenant à la famille des Cation Diffusion Facilitator. Dans le génome de P. chrysosporium, onze transporteurs de manganèse appartenant à différentes familles de gènes ont été identifiés. Le niveau d'expression de ces différents gènes a été étudié notamment en condition lignolytique. Ces transporteurs ont également été clonés afin de vérifier leurs fonctions par complémentation en système hétérologue. Cette étude a permis de mettre en évidence les transporteurs de manganèse putatifs de nombreux organismes fongiques, ainsi que l'absence d'une famille de transporteurs impliquée dans les mouvements de manganèse chez S. cerevisiae
P. chrysosporium is a saprophytic fungus able to degrade many xenobiotics which makes it particularly attractive for applications in bioremediation. Several publications highlight the importance of metal homeostasis in the production of lignolytics enzymes. Indeed the presence of manganese is required for the production of manganese peroxidase. Conversely, deficiency allows the production of lignins peroxidases. Characterization of transporters involved in the control of manganese homeostasis has been only researched in the model S. cerevisiae. Analysis of putative manganese transporters of 26 fungal species representing 20 orders of fungus was used to form a repertory of 281 transporters of manganese. Phylogenetic analysis allowed to highlight that duplication process, but also deletion, had occurred particularly in S. cerevisiae. However this one is devoid of transporters belonging to the manganese Cation Diffusion Facilitator. Eleven transporters belonging to gene families in which manganese transporters have been found were identified in the P. chrysosporium?s genome. Expression level of these genes was examined particularly in ligninolytic condition. Transporters have also been cloned in order to verify their functions by complementation in heterologous system. This study allowed to identify putative manganese transporters of numerous fungal organisms and the lack of a transporters family involved in the manganese transport in S. cerevisiae

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16

Pava-Ripoll, Monica P. "Genetic diversification, saprophytic competence and genetic enhancement of the entomopathogenic fungus (Metarhizium)." College Park, Md.: University of Maryland, 2009. http://hdl.handle.net/1903/9881.

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Thesis (Ph. D.) -- University of Maryland, College Park, 2009.
Thesis research directed by: Dept. of Entomology. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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17

O'Brien, Tammatha Rose. "(Metarhizium anisopliae's) persistence as a saprophyte, genetic basis of adaptation and role as a plant symbiont." College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8839.

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Thesis (Ph. D.) -- University of Maryland, College Park, 2008.
Thesis research directed by: Dept. of Entomology. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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18

McCarren, Kathryn. "Saprophytic ability and the contribution of chlamydospores and oospores to the survival of Phytophthora cinnamomi." Thesis, McCarren, Kathryn (2006) Saprophytic ability and the contribution of chlamydospores and oospores to the survival of Phytophthora cinnamomi. PhD thesis, Murdoch University, 2006. https://researchrepository.murdoch.edu.au/id/eprint/190/.

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Phytophthora cinnamomi has been recognised as a key threatening process to Australia's biodiversity by the Commonwealth's Environment Protection and Biodiversity Conservation Act 1999. Despite over 80 years of extensive research, its exact mode of survival is still poorly understood. It is widely accepted that thin- and thick-walled chlamydospores are the main survival propagules while oospores are assumed to play no role in the survival of the pathogen in the Australian environment, yet evidence is limited. The saprophytic ability of the pathogen is still unresolved despite the important role this could play in the ability of the pathogen to survive in the absence of susceptible hosts. This thesis aimed to investigate chlamydospores, oospores and the saprophytic ability of P. cinnamomi to determine their contribution to survival. Phytophthora cinnamomi did not show saprophytic ability in non-sterile soils. The production of thick-walled chlamydospores and selfed oospores of P. cinnamomi in vitro was documented. Thick-walled chlamydospores were sporadically formed under sterile and non-sterile conditions in vitro but exact conditions for stimulating their formation could not be determined. The formation of thick-walled chlamydospores emerging from mycelium of similar wall thickness was observed, challenging the current knowledge of chlamydospore formation. Selfed oospores were abundant in vitro on modified Ribeiro's minimal medium in one isolate. Three other isolates tested also produced oospores but not in large numbers. Although the selfed oospores did not germinate on a range of media, at least 16 % were found to be viable using Thiozolyl Blue Tetrazolium Bromide staining and staining of the nuclei with 4', 6-diamidino-2-phenylindole.2HCl (DAPI). This indicated the potential of selfed oospores as survival structures and their ability to exist dormantly. The ability of phosphite to kill chlamydospores and selfed oospores was studied in vitro. Results challenged the efficacy of this chemical and revealed the necessity for further study of its effect on survival propagules of P. cinnamomi in the natural environment. Phosphite was shown to induce dormancy in thin-walled chlamydospores if present during their formation in vitro. Interestingly, dormancy was only induced by phosphite in isolates previously reported as sensitive to phosphite and not those reported as tolerant. Chlamydospores were produced uniformly across the radius of the colony on control modified Ribeiro's minimal medium but on medium containing phosphite (40 or 100 mcg ml-1), chlamydospore production was initially inhibited before being stimulated during the log phase of growth. This corresponded to a point in the colony morphology where mycelial density changed from tightly packed mycelium to sparse on medium containing phosphite. This change in morphology did not occur when the pathogen was grown on liquid media refreshed every four days, and chlamydospores were evenly distributed across the radius of these colonies. This trend was not observed in selfed oospores produced in the presence of phosphite. Selfed oospore production was found to be inhibited by phosphite at the same concentrations that stimulated chlamydospore production. Isolates of P. cinnamomi were transformed using a protoplast/ polyethylene glycol method to contain the Green Fluorescent Protein and geneticin resistance genes to aid in future studies on survival properties of the organism. Although time constraints meant the stability of the transgene could not be determined, it was effective in differentiating propagules of the transformed P. cinnamomi from spores of other microrganisms in a non-sterile environment. Two different sized chlamydospores (approximately 30 mcg diameter and < 20 mcg diameter) were observed in preliminary trials of transformed P. cinnamomi inoculated lupin roots floated in non-sterile soil extracts and these were easily distinguished from microbial propagules of other species. The growth and pathogenicity was reduced in two putative transformants and their ability to fluoresce declined over ten subcultures but they still remained resistant to geneticin. This study has improved our knowledge on the survival abilities of P. cinnamomi in vitro and has provided a useful tool for studying these abilities under more natural glasshouse conditions. Important implications of phosphite as a control have been raised.

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19

McCarren, Kathryn. "Saprophytic ability and the contribution of chlamydospores and oospores to the survival of Phytophthora cinnamomi." McCarren, Kathryn (2006) Saprophytic ability and the contribution of chlamydospores and oospores to the survival of Phytophthora cinnamomi. PhD thesis, Murdoch University, 2006. http://researchrepository.murdoch.edu.au/190/.

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Phytophthora cinnamomi has been recognised as a key threatening process to Australia's biodiversity by the Commonwealth's Environment Protection and Biodiversity Conservation Act 1999. Despite over 80 years of extensive research, its exact mode of survival is still poorly understood. It is widely accepted that thin- and thick-walled chlamydospores are the main survival propagules while oospores are assumed to play no role in the survival of the pathogen in the Australian environment, yet evidence is limited. The saprophytic ability of the pathogen is still unresolved despite the important role this could play in the ability of the pathogen to survive in the absence of susceptible hosts. This thesis aimed to investigate chlamydospores, oospores and the saprophytic ability of P. cinnamomi to determine their contribution to survival. Phytophthora cinnamomi did not show saprophytic ability in non-sterile soils. The production of thick-walled chlamydospores and selfed oospores of P. cinnamomi in vitro was documented. Thick-walled chlamydospores were sporadically formed under sterile and non-sterile conditions in vitro but exact conditions for stimulating their formation could not be determined. The formation of thick-walled chlamydospores emerging from mycelium of similar wall thickness was observed, challenging the current knowledge of chlamydospore formation. Selfed oospores were abundant in vitro on modified Ribeiro's minimal medium in one isolate. Three other isolates tested also produced oospores but not in large numbers. Although the selfed oospores did not germinate on a range of media, at least 16 % were found to be viable using Thiozolyl Blue Tetrazolium Bromide staining and staining of the nuclei with 4', 6-diamidino-2-phenylindole.2HCl (DAPI). This indicated the potential of selfed oospores as survival structures and their ability to exist dormantly. The ability of phosphite to kill chlamydospores and selfed oospores was studied in vitro. Results challenged the efficacy of this chemical and revealed the necessity for further study of its effect on survival propagules of P. cinnamomi in the natural environment. Phosphite was shown to induce dormancy in thin-walled chlamydospores if present during their formation in vitro. Interestingly, dormancy was only induced by phosphite in isolates previously reported as sensitive to phosphite and not those reported as tolerant. Chlamydospores were produced uniformly across the radius of the colony on control modified Ribeiro's minimal medium but on medium containing phosphite (40 or 100 mcg ml-1), chlamydospore production was initially inhibited before being stimulated during the log phase of growth. This corresponded to a point in the colony morphology where mycelial density changed from tightly packed mycelium to sparse on medium containing phosphite. This change in morphology did not occur when the pathogen was grown on liquid media refreshed every four days, and chlamydospores were evenly distributed across the radius of these colonies. This trend was not observed in selfed oospores produced in the presence of phosphite. Selfed oospore production was found to be inhibited by phosphite at the same concentrations that stimulated chlamydospore production. Isolates of P. cinnamomi were transformed using a protoplast/ polyethylene glycol method to contain the Green Fluorescent Protein and geneticin resistance genes to aid in future studies on survival properties of the organism. Although time constraints meant the stability of the transgene could not be determined, it was effective in differentiating propagules of the transformed P. cinnamomi from spores of other microrganisms in a non-sterile environment. Two different sized chlamydospores (approximately 30 mcg diameter and < 20 mcg diameter) were observed in preliminary trials of transformed P. cinnamomi inoculated lupin roots floated in non-sterile soil extracts and these were easily distinguished from microbial propagules of other species. The growth and pathogenicity was reduced in two putative transformants and their ability to fluoresce declined over ten subcultures but they still remained resistant to geneticin. This study has improved our knowledge on the survival abilities of P. cinnamomi in vitro and has provided a useful tool for studying these abilities under more natural glasshouse conditions. Important implications of phosphite as a control have been raised.

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20

Masaba, Dinah Mutonyi. "The role of saprophytic surface microflora in development of coffee bean disease (Colletotrichum coffeanum) in Kenya." Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302814.

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21

Petit, Karina-Ethel. "Nouveaux médicaments d'origine marine : étude chimique et pharmacologique des métabolites bioactifs du Micromycète saprophyte Penicillium waksmanii et du Cnidaire Rhytisma fulvum." Nantes, 2003. http://www.theses.fr/2003NANT30VS.

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Dans le cadre de la recherche de nouveaux métabolites marins à visée thérapeutique, deux organismes ont été étudiés : le cnidaire Rhytisma fufvum du Golfe de Djibouti et le micromycète saprophyte Penicillium waksmanii des zones conchylicoles de l'estuaire de la Loire. Plusieurs métabolites ont été isolés et identifiés : trois d'entre eux sont originaux, les quatre autres sont déjà décrits. Les propriétés biologiques de ces métabolites ont été étudiées dans le domaine de l'immunosuppression, de la neuroactivité, et des activités antifongique et cytotoxique. Le résultat le plus prometteur vient de l'activité d'une des substances originales qui potentialise le courant calcique. Outre une avancée fondamentale dans le domaine des canaux ioniques, des applications industrielles en agro-alimentaire (insecticides) ou en thérapeutique (maladie de Parkinson, troubles cardiaques) sont envisagées
As part of the research of new marine metabolites with therapeutic designs, two organisms were studied: the cnidaria Rhytisma fulvum from the Djibouti Gulf and the mould Penicillium waksmanii from the shellfish farming of the Loire estuary. Several compounds have been isolated and identified: three of them are original, four others are already described. Biological properties of these metabolites have been investigated in the field of immunosuppressive activity, neuroactivity, and antifungal and cytotoxic activities. The most promising result is the activity of one of the original compoundsf which potentiates the calcium current. Besides a fundamental progress in the field of the ionic channels, industrial applications in agribusiness (insecticides) or in therapeutic (Parkinsonism, cardiac disorders) are considered

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22

Prosper, Pascalita. "Étude cristallographique de glutathion transférases de micro-organismes impliqués dans la dégradation de la lignine : le basidiomycète Phanerochaete chrysosporium et la bactérie Sphingobium sp. SYK-6." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0155/document.

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L'étude des champignons saprophytes tel que Phanerochaete chrysosporium est fondamentale car ces organismes, capables de dégrader la lignine, ont un fort potentiel en biotechnologie. Il a été démontré que la bactérie Sphingobium sp. SYK-6 possède des enzymes (ligE, ligF et ligG) appartenant à la famille des glutathion transférases (GST) qui successivement réduisent le lien éther (rôle éthérase) entre les unités de la lignine et déglutathionylent le produit dérivé conjugué (rôle lyase). Ce travail expose les relations entre la structure et la fonction des LigE, F et G de Sphingobium sp. SYK-6 et de deux classes de GST du champignon saprophyte Phanerochaete chrysosporium : une potentiellement liée aux éthérases (GSTFuA) et une potentiellement reliée aux lyases (GST Xi). Les structures cristallographiques des GSTFuA1, 2 et 3 de P. chrysosporium ont été résolues. L'analyse des modèles a permis de révéler une nouvelle classe structurale de GST avec des propriétés uniques. Ces caractéristiques ont pu être reliées à la fonction de ligandine et au profil catalytique de cette nouvelle classe de GST. Parallèlement, les études structurales des LigE et F de Sphingobium sp. SYK-6 sont en voie d'achèvement. La structure cristallographique de la GSTX1 de P. chrysosporium présente des caractéristiques structurales spécifiques qui nous ont conduit à la proposer comme leader d'une nouvelle classe structurale nommée Xi. L'enzyme ne présente pas d'activité lyase vis-à-vis des substrats des LigG, mais en revanche possède une fonction hydroquinone réductase (GHR). Parallèlement, la LigG a été étudiée, et s'apparente structuralement et fonctionnellement la classe Oméga des GST
Phanerochaete chrysosporium is a very interesting saprophytic fungus because it decays wood, by degrading lignin while leaving cellulose which is a renewable source of energy. The soil bacterium Sphingobium sp. SYK-6 possesses enzymes (LigE, LigF and LigG) that cleave the beta-aryl ether linkage of lignin model compounds. LigE and LigF are glutathione dependent enzymes that reduce the ether bond (etherase activity) and LigG catalyzes the elimination of glutathione (lyase activity). This study presents the structure-function relationships of Lig enzymes and of two new classes of GST from P. chrysosporium : one potentially related to LigE (GSTFuA) and one potentially connected to LigG (GST Xi). The crystallographic structures of GSTFuA1, 2 and 3 from P. chrysosporium were solved. The analysis of the models reveals a new structural class of GST with unique properties. These characteristics could be connected to the ligandin function and to the catalytic pattern of this new class of GST. In parallel, structural studies of LigE and LigF from Sphingobium sp. SYK-6 are nearly completed. The crystallographic structure of the GSTX1 from P. chrysosporium exhibits specific structural properties which allowed us to define a new structural class (Xi) in the GST superfamily. The enzyme is a S-glutathionyl-(chloro)hydroquinone reductase (GHR) that does not present a lyase activity with LigG substrate. In parallel, high resolution structure of LigG was obtained; this enzyme can be related structurally and functionally to the GST Omega class

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23

Duguay, Kathleen Jane. "Direct and indirect effects of elevated UV-B radiation on the decomposing and competitive abilities of saprophytic fungi." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ33220.pdf.

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24

Ochiai, Akihito. "Physiological and X-ray crystallographic studies on plant cell wall polysaccharides-degrading lyases from plant pathogenic and saprophytic bacteria." Kyoto University, 2008. http://hdl.handle.net/2433/136591.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(農学)
甲第13864号
農博第1679号
新制||農||952(附属図書館)
学位論文||H20||N4331(農学部図書室)
UT51-2008-C780
京都大学大学院農学研究科食品生物科学専攻
(主査)教授村田幸作, 教授清水昌, 教授井上國世
学位規則第4条第1項該当

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25

Smith, Adrienne E. "Saprophytic scarabaeidae (Coleoptera) as generalists or specialists: community structure and the volatile chemical profile of decomposing dung, carrion and fungi." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1409230472.

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26

Huang, Lei. "Understanding the hypovirulence and hypervirulence of listeria monocytogenes." Thesis, Université de Paris (2019-....), 2019. http://www.theses.fr/2019UNIP7151.

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Listeria monocytogenes est une bactérie pathogène opportuniste d'origine alimentaire capable de s'adapter à des conditions de croissance stringentes. Lm est responsable de la listériose, une infection potentiellement létale touchant principalement les individus immunodéprimés et les femmes enceintes. Sa capacité à s’internaliser dans les cellules non-phagocytaires, dont les cellules épithéliales caliciformes de l'intestin, repose sur la protéine de surface InlA et constitue un aspect essentiel de sa pathogénèse. La structure phylogénétique de Lm est hétérogène, cette espèce étant classée en quatre lignées principales contenant des sous-populations clonales. Les clones CC9 et CC121 de la lignée II sont sur-représentés parmi les isolats d'origine alimentaire mais sont hypovirulents, provoquant peu d'infections humaines. En revanche, les clones CC1, CC4, et CC6 sont sur-représentés parmi les isolats d'origine clinique et sont hypervirulents. Cette thèse a pour objectif d'étudier les mécanismes moléculaires de l'hypovirulence et l'hypervirulence de Lm, ainsi que de clarifier leur contexte évolutif.Nos résultats ont montré que la quasi-totalité des isolats appartenant à CC9 et CC121 présentent des mutations conduisant à la troncation d'InlA. Nous avons mis en évidence que la pression de sélection purificatrice sur le gène inlA a été relâchée dans différents complexes clonaux de la lignée II par rapport à la lignée I. Les mutations menant à la troncation d'InlA sont ainsi apparues par sélection positive de manière indépendante dans plusieurs clones situés sur des branches phylogénétiques distantes de la lignée II, dont CC9 et CC121. La troncation d'InlA abolit la capacité de ces isolats à envahir les cellules non-phagocytaires in vitro, et à traverser la barrière intestinale in vivo. Cependant elle favorise leur capacité à former un biofilm, leur permettant ainsi de mieux coloniser les surfaces.Nous avons également montré que l'hypervirulence du clone CC1 est révélée lors de la phase intestinale de l'infection. En effet, ces isolats adhèrent de manière plus efficace aux cellules épithéliales et infectent la lamina propria sous-jacente, conduisant à une charge bactérienne plus élevée dans les villi intestinaux et les organes en aval tels que le foie et la rate. De façon surprenante, nous avons constaté un nouveau phénotype chez ces isolats hypervirulents qui forment des foyers intracellulaires de prolifération dans la couche épithéliale de l'intestin grêle, accompagnés d'une extrusion des cellules infectées. Nos résultats suggèrent que la sélection positive de la troncation d'InlA a permis une meilleure survie de CC9 et CC121 en favorisant la formation de biofilm, contribuant ainsi au succès adaptatif de CC9 et CC121 dans l'industrie agro-alimentaire en tant que saprophytes au détriment de leur virulence. Ces résultats pourraient expliquer la présence importante de ces clones dans les aliments contaminés mais leur faible association avec les cas cliniques. En revanche, les isolats du clone hypervirulent CC1 sont mieux adaptés à l'environnement du tube digestif, que nous avons associé à l'optimisation transcriptionnelle des gènes impliqués dans l'adaptation à l'hôte. Leur capacité à infecter les cellules épithéliales et ainsi à échapper à la compétition avec les autres microbes commensaux leur permettrait de mieux coloniser le tube digestif de leur hôte, tel que les vaches laitières, ce qui expliquerait leur association importante avec les produits laitiers et avec les cas de listériose humaines
Listeria monocytogenes is an opportunistic foodborne bacterial pathogen, which is ubiquitous due to its remarkable level of adaptation to challenging growth conditions. It can cause listeriosis in humans, a potentially lethal infection that mainly affects immunocompromised individuals and pregnant women. Its ability to invade non-phagocytic cells, especially small intestine epithelial goblet cells, relies on the bacterial surface protein InlA and constitutes an essential aspect of its pathogenesis. The population of Lm is heterogeneous and can be divided into four main lineages each containing clonal subpopulations. Lineage II clones CC9 and CC121 are over-represented among food isolates. However, they are hypovirulent and cause few clinical cases. In contrast, lineage I clones CC1, CC4, and CC6 are over-represented among clinical isolates and are hypervirulent. The objectives of this thesis are to understand the molecular mechanisms underlying hypovirulence and hypervirulence and the biological contexts in which they evolved.Our results first show that almost all isolates belonging to clones CC9 and CC121 harbor mutations leading to InlA truncation. Indeed, the purifying selective pressure on the inlA gene was relieved in different clonal complexes of lineage II compared to lineage I. In this background, InlA-truncating mutations evolved by positive selection independently in several phylogenetically distant lineage II clones including CC9 and CC121. InlA truncation abolished the ability of these isolates to invade non-phagocytic cells in vitro and to cross the intestinal barrier in vivo. Importantly, it also enhanced the ability of these isolates to form biofilms and therefore to colonize surfaces.We also found that CC1 displayed hypervirulence during the intestinal phase of the infection. More precisely, it showed increased efficiency during multiple steps of intestinal barrier crossing, including adhesion to villi epithelial cells and invasion of the underlying lamina propria, resulting in increased bacterial burdens in the intestinal villi and downstream organs such as the liver and the spleen. Interestingly, we observed a novel phenotype where hypervirulent isolates proliferated and spread between neighboring epithelial cells forming clonal bacterial foci, from which infected cells were extruded back into the lumen. Our results suggest that the biofilm-promoting effect of InlA truncation leads to the positive selection of InlA-truncating mutations and contributes to the successful saprophytic lifestyle of CC9 and CC121 in food production facilities at the expense of virulence. This could explain their high prevalence in contaminated food products while causing few clinical infections. In contrast, CC1 hypervirulent isolates are well adapted to the host gut environment, which we associated to the transcriptional optimization of genes that contribute to host adaptation. Their ability to infect epithelial cells and avoid competition with gut commensals could allow them to better colonize the gut of their hosts such as dairy cattle, thus accounting for their increased association to dairy products and subsequently their high association to human listeriosis cases

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INOKUTI, Eliane Mayumi. "Comparação de iscas para quantificação da atividade saprofítica de Rhizoctonia ssp. no solo e relação com atividade patogênica." Universidade Federal Rural de Pernambuco, 2012. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6557.

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The fungi Rhizoctonia spp. is an important soilborne plant pathogen. The objective of this study was to evaluate the effectiveness of baits to quantify the saprophytic activity of Rhizoctonia in soil and determine the relationship between saprophytic and pathogenic activities in order to fit an equation of pathogenic activity risk in soils for cowpea and common bean planting. In the evaluation of baits, soils from three locations were packed in trays and infested with an isolate of R. solani (50 mg colonized substrate kg-1 soil). After seven days, soil samples were transferred to gerboxes and sown six baits: beet, cowpea, maize and sorghum seeds, cowpea segment stalks and toothpick segments. After 48 h at 25 ° C, the baits were transferred to the Ko & Hora modified medium. The wood toothpick bait led to the detection of higher levels of saprophytic activity in all soils. The bait toothpick was evaluated against eight isolates and six inoculum densities of R. solani, demonstrating highly effective in all situations. In the analysis of the relationship between saprophytic and pathogenic activities, were used 12 soils collected in areas for cowpea and common bean planting. The saprophytic activity was evaluated using toothpick baits and the pathogenic activity was assessed by the distribution of soils in trays, planting of cowpea seeds and assessment of Rhizoctonia canker severity. There was a significant (P≤0.05) positive correlation (r = 0.7698) between the saprophytic (ATS) and pathogenic (ATP) activities. The regression equation ATP = 1 / (0.5822 to 0.0056 ATS) was estimated with high precision (R2 = 0.9930, P≤0.05), indicating that the risk of pathogenic activity of Rhizoctonia in soils for cowpea and common bean planting can be estimated from the analysis of saprophytic activity.
O fungo Rhizoctonia spp. é um importante fitopatógeno habitante do solo. O objetivo deste trabalho foi avaliar a eficácia de iscas para quantificação da atividade saprofítica de Rhizoctonia no solo e determinar a relação entre atividade saprofítica e atividade patogênica, visando ajustar uma equação de risco de atividade patogênica em áreas destinadas ao plantio de feijão-caupi e feijão-comum. Na avaliação das iscas, solos de três localidades foram acondicionados em bandejas e infestados com um isolado de R. solani (50 mg de substrato colonizado kg-1 solo). Após sete dias, amostras dos solos foram transferidas para caixas gerbox e semeadas seis iscas: sementes de beterraba, feijão-caupi, milho e sorgo, segmentos de talos de feijão-caupi e segmentos de palito de dente. Após 48 h a 25 ºC, as iscas foram transferidas para o meio de Ko & Hora modificado. A isca de palito de dente de madeira propiciou a detecção dos maiores níveis de atividade saprofítica em todos os solos. A isca de palito de dente foi avaliada em relação a oito isolados e seis densidades de inóculo de R. solani, demonstrando elevada eficácia em todas as situações. Na análise da relação entre as atividades saprofítica e patogênica, foram utilizados 12 solos coletados em áreas destinadas ao cultivo de feijão-caupi e feijão-comum. A atividade saprofítica foi avaliada com iscas de palito de dente e a atividade patogênica foi avaliada pela distribuição dos solos em bandejas, plantio de sementes de feijão-caupi e avaliação da severidade da rizoctoniose. Houve correlação positiva (r = 0,7698) significativa (P≤0,05) entre as atividades saprofítica (ATS) e patogênica (ATP). A equação de regressão ATP=1/(0,5822-0,0056 ATS) foi estimada com elevada precisão (R2 = 0,9930; P≤0,05), indicando que o risco de atividade patogênica de Rhizoctonia nos solos destinados ao cultivo de feijão-caupi e feijão-comum pode ser estimado a partir da análise da atividade saprofítica.

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Pinochet, Xavier. "Etude du comportement saprophyte de deux populations de Bradyrhizobium japonicum introduites dans le sol : conséquences sur le pouvoir infectieux et sur la compétition entre souches pour la formation des nodosités." Lyon 1, 1992. http://www.theses.fr/1992LYO10059.

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L'utilisation efficace d'une population de bradyrhizobium japonicum, bacterie symbiotique du soja, necessite des connaissances sur les interactions qu'elle developpe avec le milieu tellurique. Ces interactions sont abordees a trois niveaux. Au niveau du champ, sur parcelles non contaminees par bradyrhizobium japonicum, des comparaisons multilocales des souches g49 et smgs1 ont permis de mettre en evidence la moindre sensibilite de la nodulation de smgs1 aux facteurs de l'environnement. L'importance des facteurs climatiques est preponderante, cependant des differentes de comportement peuvent etre induites dans certains types de sol. Sur parcelles deja contaminees par la souche g49, l'inoculation de smgs1 a permis d'obtenir son implantation importante au niveau des nodosites. Les resultats obtenus dependent principalement de la nature de la souche g49 et de la technologie mise en uvre pour l'inoculation de smgs1. Lors d'etudes conduites sur echantillons de terre tamisee, nous avons pu mettre en evidence l'existence d'une fraction de chaque population introduite, plus liee aux particules de terre, et qui echappe aux techniques classiques de denombrement. Des variations de comportement sont constatees selon la nature de la souche utilisee et selon l'echantillon de terre. Nous avons emis l'hypothese qu'un lien plus etroit avec les particules de terre confere a la population de bradyrhizobium japonicum consideree un etat physiologique favorisant l'expression de son pouvoir infectieux. L'etude des liens entre bacterie et particules de terre est abordee par des mesures des charges de surface

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Verdin, Anthony. "Etude du prélèvement, du stockage et de la dégradation in vitro des hydrocarbures polycycliques aromatiques par deux champignons telluriques : un champignon saprophyte, Fusarium solani et un champignon endomycorhizien, Glomus intraradices." Littoral, 2004. http://www.theses.fr/2004DUNK0124.

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L'objectif de ce travail est de mieux comprendre les mécanismes physiologiques et moléculaires mis en oeuvre par deux champignons telluriques pour dégrader les hydrocarbures polycycliques aromatiques en culture in vitro : le saprophyte Fusarium solani et le champignon endomycorhizien Glomus intraradices. Fusarium solani est capable de prélever les HPAs de façon passive et de les stocker dans des vésicules lipidiques. Une analyse des lipides totaux nous a permis de démontrer que le benzo[a]pyrène perturbe la synthèse lipidique au niveau quantitatif. F. Solani dégrade les HPAs grâce à l'utilisation de systèmes enzymatiques intracellulaires. Les lignine oxydases non spécifiques (laccases, peroxydases)ne sont pas induites en présence de HPAs. L'implication des monooxygénases à cytochromes P450 a été démontrée. Une induction de la NADPH-cytochrome P450 réductase, unique système donneur d'électrons aux cytochromes P450, a été mise en évidence lorsque F. Solani est cultivé en présence de benzo[a]pyrène. Une approche protéomique a également révélé l'induction de polypeptides spécifiquement induits en présence de benzo[a]pyrène. Deux polypeptides présentent une forte homologie avec une porphobilinogène désaminase, enzyme-clé dans la synthèse des groupements uroporphyrinogènes, éléments structural de base des cytochromes. L'utilisation d'un système de culture monoxénique de racines (carotte ou chicorée) transformées par Agrobacterium rhizogenes et colonisées par Glomus intraradices, a permis de mettre en évidence la capacité de ce champignon endomycorhizien à prélever, stocker et dégrader les HPAs
The aim of this work was a better understanding of physiological and molecular mechanisms involved in polycyclic aromatic hydrocarbon metabolism by two fungi : the saprophytic fungus Fusarium solani and the endomycorrhizal fungus Glomus intraradices. Fusarium solani is able to passively uptake PAHs from the medium and accumulate PAHs in lipid bodies. Total lipid analysis showed that benzo[a]pyrene disturbed quantitative lipid synthesis. PAH degradation involved intracellular enzymatic systems. Non specific lignin oxidases (laccases, peroxidases) were not induced in the presence of PAHs. The involvement of cytochrome P450 monooxygenases was demonstrated. The induction of the NADPH-cytochrome P450 reductase, the sole electron donor to cytochromes P450, was pointed out when the fungus was grown in the presence of benzo[a]pyrene. A proteomic approach revealed the induction of polypeptides specifically induced in the presence of benzo[a]pyrene. Two polypeptides showed high homologies with a porphobilinogen deaminase, a key-enzyme of the biosynthesis pathway of uroporphyrinogen, a constitutive element of cytochrome. The use of monoxenic cultures of roots transformed with Agrobacterium rhizogenes and colonized by Glomus intraradices pointed out the ability of this endomycorrhizal fungus to uptake from the medium, to accumulate and to degrade PAHs. Root colonization by G. Intraradices significantly enhanced root growth and pollutant degradation. A good correlation between peroxidase activities and PAH degradation was established

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Esteves, Ivania. "Factors affecting the performance of Pochonia chlamydosporia as a biological control agent for nematodes." Thesis, Cranfield University, 2007. http://dspace.lib.cranfield.ac.uk/handle/1826/8076.

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The work developed in this thesis aimed to increase understanding about the variability and stability in eleven biotypes of Pochonia chlamydosporia, a facultative parasitic fungus with potential as a biological control agent against root-knot (Meloidogyne spp.), false root-knot (Naccobus spp.) and cyst nematodes (Heterodera and Globodera, spp.). Differences in performance were assessed by measuring saprophytic and parasitic growth using in vitro bioassays. Information on virulence (in vitro) was collected for a range of biotypes with the objective to relate in vitro parasitic growth with rhizosphere colonisation ability and secretion of extracellular enzymes. Results showed differences between biotypes in their ability to colonise the rhizosphere of plants, parasitise nematode eggs and to produce a range of extracellular enzymes but no significant relationships were found between saprophytic or parasitic growth and enzyme production. For the first time, the specific activity of protease, chitinase, esterase and lipase enzyme production by eleven biotypes of the fungus was examined. Enzymatic activity was shown to vary with the biotype and type of enzyme assayed and biotypes could be ranked according to their similarities in enzyme production A novel bioassay to estimate egg parasitism using liquid media highlighted the importance of nutrition in infection processes and suggested that all biotypes are able to infect large numbers of eggs rapidly if the conditions are favourable. The assay reliably detected fungal infection in nematode eggs within 48 hours and provided a simple, rapid assay to test the effect of specific nutrients at controlled concentrations on the infection process. Differences in infection rates between biotypes observed in previous tests on agar were not detected in the new assay in which nematode eggs and fungal conidia were added in suspension. Internal colonisation of individual whole Meloidogyne spp. eggs by P. chlamydosporia was observed using microscopy studies. The destruction of nematode eggs infected with the fungus within seven days, was confirmed. The in vitro formation of appressoria was studied in a range of P. chlamydosporia biotypes. for the first time. Biotypes were found to differ in their ability to produce appressoria but this ability was not related to differences in virulence (in vitro) against nematode eggs. Cont/d.

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Johansson, Therese. "The conservation of saproxylic beetles in boreal forest : importance of forest management and dead wood characteristics /." Umeå : Dept. of Animal Ecology, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/200666.pdf.

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Lopes, de Oliveira Veturia. "Intéractions entre les micro-organismes du sol et l'établissement de la symbiose ectomycorhizienne chez le hêtre (fagus silvatica L. ) avec hebeloma crustuliniforme (bull. Ex saint-amans) quel. Et paxillus involutus batsch. Ex fr." Nancy 1, 1988. http://www.theses.fr/1988NAN10174.

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Mise en évidence de différences de réceptivité entre cinq sols forestiers du nord-est de LA France. Effet global, et effets des composants individuels des communautés microbiennes rhizosphériques ou non des sols brun mésotrophe et brun acide sur la mycorhization du hêtre. Évaluation des possibilités offertes par les micro-organismes auxiliaires pour le contrôle biologique de la mycorhization

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33

De, Wet Juanita. "Molecular studies on the taxonomy, host-associations and viruses of the Diplodia-like anamorphs of the Botryosphaeriaceae." Thesis, 2009. http://hdl.handle.net/2263/25449.

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The Botryosphaeriaceae is a family of fungi that includes many species, which are well-known as pathogens, saprophytes and endophytes of plants and especially of trees. As a result of their pathogenic nature and potential threat to plantations and agricultural crops, much research has been devoted to their identification. The main focus of studies that make up this thesis has been on the fungal complex referred to as Diplodia pinea sensu lato. These fungi are members of the Botryosphaeriaceae and studies have specifically concentrated on their taxonomy, host associations and mycovirus infections associated with them. Diplodia pinea sensu lato represents a species complex of highly similar morphological types that mainly infect Pinus spp., world-wide. The species complex includes what have in the past been known as the A, B and C morphological types of D. pinea. Multiple gene genealogies based on sequences of partial protein-coding genes and microsatellite markers were used to resolve the species complex into two genera, D. pinea and D. scrobiculata (= B morphotype). Diplodia-like isolates from Australia, Greece and Cyprus were characterized using both morphological and molecular characteristics. Morphologically, these isolates all have dark, thick-walled conidia (Diplodia-like) but phylogenetically, they could belong to three distinct genera of the Botryosphaeriaceae namely Diplodia, Lasiodiplodia and Dothiorella. Results of this study led to the description of Dothiorella casuarini from Casuarina spp. in Australia and they highlight the fact that similar morphological characteristics and disease etiology does not necessarily provide a true reflection of the evolutionary history of a pathogen. Phylogenetic studies on species of the Botryosphaeriaceae with Diplodia-like anamorphs revealed intriguing host association patterns. The availability of sequence data for many species of the Botryosphaeriaceae made it possible to extend the phylogeny to include six of the ten lineages as previously described for the Botryosphaeriaceae. Angiosperms appeared to be the most common, and possibly ancestral, host group of the Botryosphaeriaceae, with the exception of Macrophomina, Guignardia, Saccharata and “Botryosphaeria” quercuum. Infection of gymnosperms most likely occurred more recently, only in specific groups (Diplodia and Lasiodiplodia) via host shifts. Three distinct viruses have now been characterized from isolates of D. pinea sensu lato. Two of these were previously characterized and are known as Sphaeropsis sapinea RNA virus 1 and 2 (SsRV1 and SsRV2). The third dsRNA element more commonly found in association with D. scrobiculata was characterized in this dissertation and named Diplodia scrobiculata RNA virus 1 (DsRV1). It has a genome of 5018 bp with a unique genome organization characterized by two open reading frames (ORFs). One ORF codes for a putative polypeptide similar to proteins of the vacuolar protein-sorting (VPS) machinery and the other one for a RNA dependent RNA polymerase (RdRp). The hypothetical protein probably has a role in transport or protection of this unencapsulated virus into membranous vesicles. Phylogenetically, DsRV1 groups closest to a dsRNA element from Phlebiopsis gigantea (PgV2) and they both group separately from other families in which fungal viruses have been classified. The frequency and distribution of DsRV1, SsRV1 and SsRV2 were determined in a collection of D. pinea and D. scrobiculata isolates using Real-time PCR. Infections with SsRV1 and SsRV2 occurred in both D. pinea and D. scrobiculata, while DsRV1 was mainly found in D. scrobiculata. DsRV1 was also found to always occur in combination with SsRV1 and/or SsRV2. Therefore, DsRV1 probably selected against a coat protein as the result of a fitness trade-off. Although earlier studies indicated that these viruses have no effect on the phenotype or virulence of D. pinea and D. scrobiculata isolates, the presence of specific viruses in their host populations serve as a useful marker in studying movement of fungal pathogens. The ultimate aim of studies making up this dissertation was to expand the base of knowledge regarding species in the D. pinea species complex. This was justified by the fact that D. pinea is one of the most important tree pathogens in South Africa and that an expanded knowledge might contribute to reducing diseases caused by it. Clearly understanding the identity of the fungus must clearly underpin many elements of a management strategy and this was one of the aims of the suite of studies conducted. Furthermore, I attempted to augment the knowledge base regarding dsRNA elements in D. pinea sensu lato. These studies were of a basic nature and relatively far removed from the practical application level. Nonetheless, it is my hope that they have pushed ahead knowledge barriers and that in some way they will contribute to reducing the impact of Diplodia-associated diseases in the future.
Thesis (PhD)--University of Pretoria, 2011.
Microbiology and Plant Pathology
Unrestricted

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YING, JHENG LEE, and 李尹正. "Saprophyte metropolis - Environmental Regeneration Mechanical Architecture." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/19321927318133315465.

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碩士
實踐大學
時尚與媒體設計研究所
97
Abstract This creation assignment is by “saprophyte” for create concept, “saprophyte” is in the natural ecosystem such as by animal and plant’s corpse or putrefied organization to obtain nutrient maintenance existence function of appearance, convert the concept of “saprophyte” is through the from of “mechanical architecture”, create a kind of saprophyte machinery adhere to on the lifeless land. By suffered serious and polluted ecosystem environment, combine different decontamination science and technology of the environment by “machine building" and construct function of systematizing the city, carry on the constructing of rebirth and machine city of natural environment, present " saprophyte city " that building and natural environment of the differences machine coexist , put forward another new possibility for the urban planning and the building design, extend more possibilities and development that the city turns into with building type in the future. This creative research will penetrate: (1) literature review and analysis; (2) concept operation and transformation; (3) mechanical architecture concept and design; above three parts carry on research and create an experiment. (1) Literature review and analysis This literature review uses “the architecture concept” and “the science fiction theme” two parts as discussions, “the architecture concept” is mainly with ideal imagination city concept (Archigram Group) with building, machine and technology of the history turn into be create data analysis; on the other hand “the science fiction theme” uses machine science and technology meaning in the movie and the animate science fiction movie influence of the from USA and Japan are the foundation which creates a direction. (2) Concept operation and transformation 1. Concept operation: From future with the machine function of the city and the structure organization of the microorganism is the concept experiments which prognosticated in the early years, imitate the organization of type and microorganism of activity affairs in the city, by “the movement”, “the parasitism”, “the joined bodies” three kinds of types are the prototype concepts which build machine body. 2. Concept transformation: Three kinds of concept as “the movement”, “the parasitism” and “the joined body” establish for the prototype of ”systematize” and ” variability”, “systematize” is the integration system of city environment and “variability” is the flexible that the city environment reforms. (3) Mechanical architecture concept and design Develop into seven machine bodies which have different decontamination on science and technology environment and construct saprophyte city through the prototype. Therefore saprophyte city has the function of environment rebirth; continue the development of the city organic.

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Chou, Chi-Miao. "Morphology and Taxonomy Studies on Saprophytic Discomycetes from Taiwan." 2000. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0021-2603200719104539.

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Chi-Miao, Chou, and 周季妙. "Morphology and Taxonomy Studies on Saprophytic Discomycetes from Taiwan." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/92751378907853598725.

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碩士
國立臺灣師範大學
生物研究所
89
A b s t r a c t Some indiginar species of saprophytic discomycetes were collected from Taiwan. Total twenty-one species belonging to 12 genera, 8 families, 5 orders were examined and studied. The identified species including: Galiella javanica, Lachnum flavidulum, Lachnum oncospermatis, Lachnum pteridophyllum, Lachnum taxonomia sp. #1, Lachnum virgineum, Lachnum controversum, Lachnum nudipus, Lachnum apala, Lachnum brasiliense, Lachnum sclerotii, Psilachnum chrysostigma, Orbilia curvatispora var. minor, Bisporella claroflava, Hymenoscyphus sp., Dicephalospora rufucornea, Asterocalyx mirabilis, Stictis radiata, Karstenia idaei, Rhytidhysteron rufulum, Patellaria atrata, Among them, 7 species including: L. controversum, O. curvatispora var. minor, A. mirabilis, S. radiat, K. idaei and P. atrata, are recorded for the first time from Taiwan, and L. taxonomia sp.#1 and Hymenoscyphus sp. were different from any discomycetes been reported from the world and could be two new species.

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Yap, Kathryn H. M. "Symbiotic and saprophytic characteristics of a soil population of Rhizobium leguminosarum bv. trifolii." Thesis, 1991. http://hdl.handle.net/1957/37408.

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Although much has been learned about the comparative nodulating behavior of simple mixtures of rhizobial strains under non-soil situations, it is unclear how these findings relate to the factors influencing nodulation success by the complex mixtures of strains found within soil-borne rhizobial populations. Information on the structure and physiological behavior of soil populations is almost nonexistent. To achieve a better understanding of the situation in soil, studies were carried out with the following objectives. (i) To delineate by serological analysis the population composition of nodule occupants of Rhizobium leguminosarum bv.trifolii recovered from a variety of annual and perennial clover (Trifolium) species planted into Abiqua soil. (ii) To further the development of an assay to evaluate the substrate responsiveness of specific indigenous serotypes of R. leguminosarum bv. trifolii while they reside within the soil microbial community. Immunodiffusional analysis of isolates recovered from nodules of five annual (T. subterraneum, T. incarnatum, T. vesiculosum, T. parviflorum, T. patens) and three perennial (T. pratense, T. repens, T. hybridum) species of clover revealed that the serotypic composition of the natural population of R. leguminosarum bv. trifolii in Abiqua soil is almost completely known. With antisera to 14 antigenically distinct serotypes at our disposal, only 19 of 272 isolates recovered from these eight clover species were antigenically unknown. While the perennial species showed no pronounced preference for particular serotypes, a substantial proportion (37-75%) of nodule occupants from each of the annual clovers (with the exception of T. vesiculosum) reacted with antiserum AS6. These isolates could be subdivided by their serological reactions of non-identity with either antisera AS6, AS27, or both antisera AS21 and AS27. Using multi-locus allozyme electrophoresis (MLAE) to analyze population structure within serotypes, isolates representing serocluster AS6 were found to be rooted at a similarity of 0.82 and clustered with the other three serotypes (AG4, AS21, and AS27) only at a similarity of 0.37. In contrast to AS6, MLAE analysis revealed that "genotypic distances" between the 7 ETs representing AG4 could be large. The chapter on the nalidixic acid cell-elongation assay only represents the second report of its use on soil microbial populations. Nalidixic acid was found to be the most suitable DNA gyrase inhibitor for rhizobial studies since norfloxacin and ciprofloxacin at extremely low concentrations (2.0 and 0.5 mg/l, respectively) reduced the proportion of elongating cells significantly. In contrast to other indigenous serotypes, the majority of members of serotype AR23 did not elongate in response to yeast extract (YE). Regardless of nutrient type, or concentration, the percentage of elongated cells of AR23 remained low (<16%) even after 24 h of incubation. While the cell elongation response of serotype AS6 occured more rapidly to YE than did AR23, a less vigorous response by AS6 was observed when other nutrient sources were used. The appearance of elongated cells was delayed and the final percentage of elongated cells was reduced.
Graduation date: 1992

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38

Su, Yu-Chih, and 蘇毓智. "Morphological Taxonomy and Species Assemblages of Saprophytic Discomycetes in Tengjhih and Shanping, Taiwan." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/02408361197656776593.

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碩士
國立高雄師範大學
生物科學研究所
94
In order to understand the species diversity of saprophytic Discomycetes in southern Taiwan, field expedition were made in Tengjhih and Shanping, Kaohsiung County. Sample collection were made twice per month from November 2004 to January 2006. A transect with approximately one kilometer was selected in both sampling areas. In addition to indentification, seasonal dynamic of assemblages were also analyzed. Forty-six species of 15 genus, 7 families and 3 orders were identified. Forty-one species were collected from Tengjhih and 23 species were from Shanping. Eighteen species were discovered in both areas. Lachnum pteridophyllum was the dominant species among 41 identified species in Tengjhih and Lachnum lanariceps was the dominant species among 23 identified species in Shanping. The result of Cluster Analysis shows that the assemblage of Discomycetes in Tengjhih is varied among the seasons, but that of Shanping is not. Lachnum brasiliense, Lachnum controversum, Lachnum pteridophyllum and Lachnum lanariceps have the widest growing temperature range. Finally, 2 new species including Hyalorbilia arcuata and Hyalorbilia biguttulata as well as 7 new records including Orbilia cf. luteorubella, Orbilia cf. querci, Albotricha cf. albotestacea, Lachnum cf. alnifolium, Lachnum lanariceps, Lachnum lushanense and Lachnum cf. macrosporum were reported in this study. The taxonomic characteristics of all species were discussed in detail.

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39

Norman, Bret Lane. "Selecting biological control agents to limit the saprophytic ability of Pyrenophora tritici-repentis." 1987. http://hdl.handle.net/2097/22687.

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40

Adee, Eric Allen. "The effect of cultural practices on saprophytic survival of Phialophora gregata and severity of brown stem rot of soybean." 1993. http://catalog.hathitrust.org/api/volumes/oclc/30343703.html.

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Dissertations / Theses on the topic 'Saprophytes'

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