Dissertations / Theses on the topic 'Sclerotial'

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1

Bhagat, Indramani. "Studies on sclerotial of tea and its management." Thesis, University of North Bengal, 2006. http://hdl.handle.net/123456789/1020.

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2

ul, Haq M. Anwar. "White rot of onion-plant response and detection." Thesis, University of Liverpool, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367806.

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3

Couch, Brett Charles. "Population biology of Sclerotium cepivorum." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0004/MQ45399.pdf.

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4

Na, Lampang Acharaporn. "Study on interactions between Sclerotium rolfsii Sacc. and selected antagonists." Title page, table of contents and abstract only, 1994. http://web4.library.adelaide.edu.au/theses/09PH/09phn165.pdf.

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5

Kelkar, H. S. "Studies on pullulan-hydrolysing activity from sclerotium rolfsii." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 1991. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/5963.

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6

Mitra, Pankaj. "Chemical induction of resistance in soybean plants to sclerotium rolfsii Sacc." Thesis, University of North Bengal, 2002. http://hdl.handle.net/123456789/1017.

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7

Noe, Montes Garcia, and Montes Garcia Noe. "Epidemiological aspects of Claviceps africana, causal agent of Sorghum ergot." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1546.

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Sorghum ergot, caused by Claviceps africana Frederickson, Mantle & de Milliano, is a disease that affects non-fertilized ovaries in sorghum male-sterile plants and infects hybrids if there is pollen sterility at flowering time. Sphacelia containing macroconidia could play a role in the survival of the pathogen. This study developed risk assessment models and evaluated environmental conditions affecting viability of macroconidia and transition from sphacelial to sclerotial tissues. Effect of weather on ergot severity was evaluated under natural conditions (in monthly planting dates) in nine sorghum genotypes at College Station, Weslaco, Rio Bravo, and Celaya. Panicles were inoculated daily beginning at flower initiation with a suspension of 1.6 x 106 C. africana conidia ml-1. Weather triad values were used to identify weather parameters correlated with the disease. Ergot severity was statistically greater in A-lines than hybrids because of the possible interference of pollen on some dates. Celaya had the greatest amount of ergot in hybrids. A-line ATx2752 had the lowest average ergot severity throughout years, locations and planting dates, as did the hybrid NC+8R18. Maximum and minimum temperature had a negative correlation with ergot at Rio Bravo, College Station and Weslaco, while at Celaya it was positive. The highest correlation was 7 to 9 days before initiation of flowering, suggesting that cooler temperatures during this period could cause male sterility. A-lines showed the same relationships between ergot and maximum and minimum temperatures after initiation of flowering. Minimum relative humidity had a positive correlation with ergot after initiation of flowering in both sorghum plant types. Sphacelia stored under cool temperatures (-3oC to 7oC) maintained conidial viability, and newly-formed sphacelia located on the sphacelia surface had the highest conidial viability. However, they show a greater viability reduction through time compared with conidia from older sphacelia, showing that conidial maturity can play a role in the survival of the conidia. Sphacelia on plants grown at 10oC, 20oC and 30oC with low relative humidity did not had any sclerotial development up to 4 weeks after formation of sphacelia. However, higher temperatures promoted an increase in the sphacelia dry weight during that time.
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8

Qian, Yang. "Interaction of some crops with Sclerotina sclerotiorum (Lib.) de Bary." Thesis, University of Reading, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.481096.

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9

Taurhesia, Shelly. "Exopolysachharide production by submerged culture of the fungus Sclerotium glucanicum." Thesis, University of Strathclyde, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319472.

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10

Xu, Zhihan. "Overwinter survival of Sclerotium rolfsii and S. rolfsii var. delphinii, screening hosta for resistance to S. rolfsii var. delphinii, and phylogenetic relationships among Sclerotium species." [Ames, Iowa : Iowa State University], 2008.

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11

Pelzer, Gabriela Queiroz. "Mecanismos de controle da murcha-de-esclerócio e promoção de crescimento em tomateiro mediados por rizobatérias." Universidade Federal de Roraima, 2010. http://www.bdtd.ufrr.br/tde_busca/arquivo.php?codArquivo=39.

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Objetiva elucidar quais mecanismos de antagonismo são responsáveis pelo biocontrole da murcha-de-esclerócio e que fatores estão envolvidos na promoção de crescimento em tomateiro por meio de rizobactérias. Os testes foram realizados in vivo e in vitro, em que se verificaram: a capacidade de produção de enzimas líticas, antibiose por meio de compostos voláteis e difusíveis, colonização de raízes, produção de sideróforos, metalismo de carbono, produção de ácido indol acético, fixação biológico de nitrogênio, solubilização de fosfato de cálcio e promoção de crescimento do tomateiro em condições de casa-de-vegetação
This research was aiming to elucidate the antagonism mechanisms responsible for the biocontrol of southern blight and the elements involved in growth promotion in tomato by rhizobacteria. The experimental assays were performed in vivo and in vitro, and the following characteristics evaluated: production of lytic enzymes, antibioses by volatiles and diffusible compounds, root colonization, siderophores production, carbon sources metabolism, indole acetic acid production, nitrogen fixation, calcium phosphate solubilization and tomato growth promotion in greenhouse conditions
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12

Parfitt, D. "Sclerotium cepivorum Berk. in onions : An investigation of alternative methods of control." Thesis, University of Hull, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377392.

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13

SILVA, Jeferson Araújo. "Avaliação e estabilidade da resistência de genótipos de fava a Sclerotium rolfsii." Universidade Federal Rural de Pernambuco, 2011. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6571.

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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
The collar rot caused by Sclerotium rolfsii, is an important disease that causes an incidence in lima bean (Phaseolus lunatus L.) at the Northeastern of Brazil. Aiming to select genotypes with potential to be used in a disease management, there were 50 genotypes of lima bean evaluated in relation to an isolate of S. rolfsii. Plants with 10 days old were inoculated by an injury into their base and deposited the sclerotia of the pathogen. The evaluation occurred at the 10th day after the inoculating, by calculating the percentage of the number of plants with symptoms in relation to the total of plants per pot. Most part of the genotypes (58%) behaved as highly susceptible to the pathogen while 28% were classified as susceptible, 10% as moderately resistant. Only two genotypes (F-2 and F-25) behaved as extremely resistant, corresponding to 4% of the total. The stability of resistance of these two genotypes was evaluated in relation to 10 isolates of S. rolfsii. Both genotypes showed a good level of resistance, thus demonstrating the potential of its use as a strategy for management of collar rot of the lima bean crop.
A podridão do colo, causada por Sclerotium rolfsii, é uma importante doença que pode incidir em fava (Phaseolus lunatus L.) no Nordeste brasileiro. Visando selecionar genótipos com potencial de utilização no manejo da doença, foram avaliados 50 genótipos de fava, em relação a um isolado de S. rolfsii. Plantas com 10 dias de idade foram inoculadas pelo método de ferimento do colo e deposição do escleródio do patógeno. A avaliação ocorreu aos 10 dias após a inoculação pela mensuração da incidência da doença, considerando a porcentagem de plantas com sintomas em relação ao total de plantas por vaso. A maioria dos genótipos (58%) se comportou como altamente suscetível ao patógeno, enquanto que 28% foram classificadas como suscetíveis e 10% como medianamente resistentes. Somente dois genótipos (F-2 e F-25) se comportaram como altamente resistentes, correspondendo a 4% do total. A estabilidade da resistência destes dois genótipos foi avaliada em relação a 10 isolados de S. rolfsii. Ambos os genótipos apresentaram um bom nível de resistência, demonstrando potencial de utilização como estratégia de manejo da podridão do colo na cultura da fava.
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14

Haque, Md Ehsanul. "Developing a New Inoculation Method, and Evaluating the Potential Biological Control of Rhizoctonia solani by Penicillium pinophilum on Sugar Beet." Thesis, North Dakota State University, 2020. https://hdl.handle.net/10365/31822.

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Rhizoctonia solani causes damping-off, and root and crown rot of sugar beet (Beta vulgaris L.) and overwinters as sclerotia and mycelia. Research was conducted to determine how best to produce large quantities of sclerotia and mycelia in vitro, and compare their pathogenicity with traditionally used colonized barley grains to sugar beet in vitro and in vivo. The greatest number of sclerotia was produced on amended clarified V8 medium and sclerotia caused more disease compared to barley inoculum in the greenhouse. The bio-control potential of Penicillium pinophilum on R. solani AG2-2 on sugar beet was evaluated in vitro and in vivo. Results showed that the presence of P.pinophilum with R.solani reduced damping-off by 75% and thus have the potential to be developed as a bio-control agent for this pathogen.
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15

Chinnathambi, S. "Isolation, purification and characterization of alpha- arabinofuranosidase and other glycosidases from sclerotium rolfsii." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 1997. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/3289.

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16

Domingos, Luisa Bastos. "Indutores de germinação de escleródios e uso de fungicidas no manejo de Sclerotium cepivorum." Universidade Federal de Viçosa, 2015. http://www.locus.ufv.br/handle/123456789/7792.

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A podridão branca, causada pelo fungo Sclerotium cepivorum, é uma das principais doenças, que ocorre em todo o mundo, que pode causar graves perdas nos cultivos de alho (Allium sativum L.) e cebola (Allium cepa L.). Escleródios de S. cepivorum são capazes de sobreviver por até 30 anos no campo. A gama de hospedeiros do fungo compreende plantas do gênero Allium e a germinação dos escleródios é induzida pela presença de exsudatos Allium, especialmente em solos úmidos e sob condições de temperatura entre 13 – 18 ° C. A erradicação do patógeno de áreas infestadas é muito difícil e a densidade de escleródios viáveis deve ser reduzida por meio de estratégias diferentes, tais como indutores de germinação e fungicidas. A aplicação de extratos de alho em campos de pousio pode induzir escleródios a germinarem e diminuir o número de estruturas de sobrevivência viáveis. Fungicidas podem inibir a germinação de escleródios e crescimento micelial. Assim, o efeito do extrato de alho e dialil dissulfeto (DADS) sobre a germinação de esclerócios de S. cepivorum e o potencial de fungicida sobre a inibição do crescimento micelial foi avaliado neste trabalho. Extrato aquoso e etanólico de alho preparados em laboratório (20 % m:v), as águas residuais de agroindústria de alho e extrato aquoso produzido por Shimada Agronegócios (20 %, m:m) foram utilizados como indutores de germinação aos 17 e 27 °C em laboratório. Além disso, o efeito de DADS em estimular a germinação de escleródios foi avaliada usando tubos plásticos com solo e contendo escleródios enterrados a 10, 20 e 30 cm de profundidade. Todos os extratos de alho induziram a germinação dos escleródios, independentemente da temperatura avaliada. DADS induziu a germinação de escleródios de 10 a 30 cm de profundidade, embora o efeito tenha sido maior sobre escleródios localizados a 10 cm. Em outro experimento, o fungicidas tebuconazol + trifloxystrobina, trifloxistrobina + protioconazol, tebuconazol, triadimenol, tiofanato metílico e fluazinam foram adicionados a meio batata dextrose agar (BDA) + extrato aquoso de alho (20 % m:m) em volumes equivalentes a 200 e 20.000 L/ha. Discos de micélio de 5 mm de diâmetro de S. cepivorum foram removidos da borda de culturas do fungo com 15 dias de idade em BDA e colocadas no centro de placas de Petri contendo BDA + extrato de alho, com ou sem fungicidas. O fungo foi incubado a 17 ± 2 oC por 30 dias, quando o crescimento mycelial foi avaliado. Todos fungicidas reduziram o crescimento do fungo em mais de 90 %. Os fungicidas triadimenol e fluazinam inibiram completamente o crescimento de S. cepivorum, independemente do volume da solução fungicida. A eficácia de tebuconazol e tebuconazol + trifloxistrobina foi reduzida quando o volume da solução foi aumentada de 200 para 20.000 L. Extratos de alho, residuo de agroindústria de alho e DADS induzem a germinação de escleródios de S. cepivorum. Triadimenol, fluazinam, tebuconazol e tebuconazol + trifloxistrobina suprimem o crescimento de S. cepivorum in vitro, especialmente em volume de soluçãofungicida equivalente a 200 L.ha -1 . Estudos adicionais em campo são necessários para avaliar o uso integrado de extratos de alho, DADS e os fungicidas triadimenol, fluazinam, tebuconazol e tebuconazol + trifloxistrobina no manejo da podridão branca.
White rot, caused by the fungus Sclerotium cepivorum, is a major disease worldwide that can cause severe losses in garlic (Allium sativum L.) and onion (Allium cepa L.). Sclerotia of S. cepivorum are able to survive for up to 30 years in the field. The host range of the fungus comprises plants from the genera Allium and the sclerotia germination is induced by the presence of Allium exsudates, especially in moist soils and at 13 – 18 °C. Since eradication of the pathogen from infested areas is very difficult, the density of viable sclerotia must to be reduced by using different strategies, such as germination inducers and fungicides. The application of garlic extracts at fallow fields may induce sclerotia germination and decrease the number of viable resting propagules. Fungicides may inhibit sclerotia germination and mycelial growth. Thus, the effect of garlic extract and diallyl disulfide (DADS) on the germination of sclerotia of S. cepivorum and the potential of fungicides on the inhibition of mycelial growth were evaluated in this work. Aqueous and ethanolic extracts of garlic prepared in laboratory (20 % m:v), wastewater of garlic agroindustry and aqueous extract produced by Shimada Agronegócios (20 % m:m) were used as germination inducers at 17 and 27 °C in laboratory. In addition, the effect of DADS in stimulating germination of sclerotia was assessed using plastic tubes filled with soil and containing sclerotia buried at 10, 20 and 30 cm depth. All extracts stimulated sclerotia germination, regardless the temperature. DADS induced germination of sclerotia at 10 to 30 cm depth, although the effect was higher at 10 cm. In other experiment, the fungicides tebuconazole + trifloxystrobin, trifloxystrobin + protioconazole, tebuconazole, triadimenol, thiophanate methyl and fluazinam were added into potato dextrose agar (PDA) + garlic aqueous extract (20 % m:m) broth at dosages equivalent to 200 and 20.000 L.ha -1 . Mycelial discs (5 mm in diameter) of S. cepivorum were removed from the border of 15 day cultures in PDA cultures and placed on the center of Petri dishes with PDA+garlic aqueous extract, amended or not with fungicides. The fungus was incubated at 17 ± 2 oC for 30 days, when the mycelial growth was assessed. All fungicides reduced the growth of the fungus by more than 90 %. The fungicides triadimenol and fluazinam inhibited completely the growth of S. cepivorum, regardless the volume of the solution. The efficacy of tebuconazole and tebuconazole + trifloxystrobin was reduced when the volume of the soultion was increased from 200 to 20.000 L. Garlic extracts, wastewater of garlic agroindustry and DADS induce germination of sclerotia of S. cepivorum. Triadimenol, fluazinam, tebuconazole and tebuconazole+trifloxystrobin suppress the growth of S. cepivorum in vitro, especially at the volume of fungicide solution equivalent to 200 L.ha -1 . Further studies under field conditions are needed to evaluate the integrated use of garlic extracts, DADS and the fungicides triadimenole, fluazinam, tebuconazole and tebuconazole + trifloxystrobin on the management of the white rot.
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17

Barbosa, Rosianne Nara Thomé. "Seleção de rizobactérias visando o controle biológico da murcha-de-esclerócio em tomateiro (Solanum lycopersicum L.)." Universidade Federal de Roraima, 2009. http://www.bdtd.ufrr.br/tde_busca/arquivo.php?codArquivo=21.

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A murcha-de-esclerócio causada por Sclerotium rolfssi é uma das mais importantes doenças do tomateiro em regiões tropicais. O presente trabalho foi realizado com o objetivo de selecionar rizobactérias que promovem o controle da murcha-de-esclerócio sem afetar o crescimento das plantas de tomateiro e verificar se o mecanismo de antiobiose e a inibição da difusão do ácido oxálico têm relação com a capacidade de controle.
The southern blight caused by Sclerotium rolfsii is one of the most important diseases of tomato in tropical countries. The aim of this work was select rhizobacteria capable to control the southern blight with no effect on tomato growth and investigative the correlation of antibiosis mechanism and inhibition of oxalic acid diffusion with the control of disease
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18

Bueno, César Júnior [UNESP]. "Produção e preservação de estruturas de resistência de fungos fitopatogênicos habitantes do solo." Universidade Estadual Paulista (UNESP), 2004. http://hdl.handle.net/11449/105441.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Universidade Estadual Paulista (UNESP)
Os fungos fitopatogênicos habitantes de solo causam grandes perdas em culturas econômicas. Estes organismos, por produzirem estruturas de resistência na ausência de hospedeiros e/ ou condições climáticas desfavoráveis, inviabilizam o controle do patógeno. A preservação de fungos por longos períodos é importante para que pesquisas possam ser realizadas a qualquer tempo. O método de manutenção destes organismos requer que sejam conservados em baixa atividade biológica para preservar as características de esporulação e patogenicidade. O objetivo deste trabalho foi desenvolver metodologias para produzir, avaliar a sobrevivência e preservar as estruturas de resistência dos fungos Fusarium oxysporum f.sp. lycopersici raça 2, Macrophomina phaseolina, Rhizoctonia solani GA4 HGI, Sclerotium rolfsii, Sclerotinia sclerotiorum e Verticillium dahliae. O primeiro experimento foi feito no delineamento de parcelas inteiramente casualizadas em que a sobrevivência das estruturas de resistência dos seis fungos foi avaliada mensalmente por seis meses, em condições de campo e de laboratório. Para tanto, estruturas de cada fungo, produzidas através das metodologias desenvolvidas, foram enterradas no campo a 10 cm de profundidade e outras mantidas no laboratório. O objetivo deste experimento foi verificar a eficiência das metodologias para manter e também para avaliar a capacidade da sobrevivência dos patógenos, permitindo desta forma, manusear as estruturas de resistência de todos os fungos estudados. No segundo experimento, frascos de 500 mL (duas repetições/fungo) contendo estruturas de resistência, produzidas através das 2 metodologias desenvolvidas, foram mantidos em temperatura natural de laboratório, de refrigeração (º5C) e de freezer (-20ºC) para determinar a melhor condição para preservar as estruturas de cada fungo...
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Mesquita, Déborah Christina Moraes. "Compatibilidade micelial de Sclerotium cepivorum e reação de genótipos de alho e cebola à podridão branca." reponame:Repositório Institucional da UnB, 2018. http://repositorio.unb.br/handle/10482/32480.

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Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Fitopatologia, Programa de Pós-Graduação em Fitopatologia, 2018.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) e Fundação de Apoio a Pesquisa do Distrito Federal (FAP-DF).
As culturas do alho (Allium sativum) e da cebola (Allium cepa) destacam-se no Brasil e no mundo entre as hortaliças mais expressivas economicamente. Entretanto, ambas têm sido comprometidas pela podridão branca, doença ocasionada por Sclerotium cepivorum, um patógeno restrito a espécies de Allium. Presentemente não existem medidas eficientes de controle a podridão branca, mas o conhecimento da reação de genótipos de alho e cebola pode auxiliar no manejo da doença. Também pouco se sabe sobre a variabilidade do patógeno no Brasil, e a compatibilidade micelial pode ser utilizada para estimar esta variabilidade indiretamente. Desta forma, este estudo se propõe a: (i) avaliar a variabilidade de uma coleção de isolados de S. cepivorum brasileiros obtidos de cultivos de cebola e alho com o teste de compatibilidade micelial, e (ii) avaliar a reação de genótipos de cebola e alho a S. cepivorum em condições de cultivo comercial em campo. Inicialmente, a identificação de todos os isolados de S. cepivorum foi confirmada pela comparação de sequências do rDNA. Para análise de DNA, o DNA genômico total foi extraído e amplificado com os primers ITS1 e ITS4 para amplificar as regiões ITS1, ITS2 e 5.8S do DNA ribossômico. Posteriormente 52 isolados de diversas áreas produtoras de Allium sp. foram selecionados para a análise de compatibilidade micelial, em que foram confrontados todos os isolados em todas as combinações possíveis. Dois grupos de compatibilidade foram identificados. Segundo a análise do teste de compatibilidade, o grupo de 52 isolados apresenta indícios de baixa variabilidade genotípica, sendo predominantemente clonal. A resposta de genótipos de Allium spp. à prodridão branca foi avaliada em campo em 2016 e 2017. Em 2016 foi avaliada a resposta de 20 genótipos de alho e 30 de cebola, e em 2017, 12 de alho e 30 de cebola. Alguns genótipos testados em 2016 foram repetidos em 2017, como controle. Os experimentos foram conduzidos na estação experimental da Cooperativa Agropecuária do Alto Paranaíba – COOPADAP em Rio Paranaíba/MG no período de maio a setembro de 2016 e 2017. As áreas utilizadas para estes experimentos encontravam-se naturalmente infestadas com microescleródios de S. cepivorum, devido a cultivos anteriores e sucessivos de alho e cebola. Os genótipos de alho e cebola testados variaram quanto à reação à podridão branca. Dentre os genótipos de alho os que apresentaram a menor sucetibilidade e a maior produtividade foram UO 73, DDR 6024 e RAL 127. Entre os genótipos de cebola, Optima F1, Sirius F1, Franciscana IPA10, Shinju F1 e Perfecta F1 destacaram-se como os genótipos com o menor sucetibilidade e com as maiores produtividades. No segundo ano de experimento, onde as temperaturas foram mais baixas que no primeiro ano, os índices de doença foram extremamente altos e não foi possível a separação dos genótipos quanto a susceptibilidade ou resistência a doença. Ressalta-se que devido ao padrão de resposta aferido no primeiro ano de estudo, existem variações na resposta dos genótipos de alho e cebola à podridão branca que devem ser considerados do ponto de vista do manejo da doença, com também em programas de melhoramento.
Garlic (Allium sativum) and onion (Allium cepa) are among the economically most important vegetable crops in Brazil and worlwide. However, both garlic and onion sustain high losses due to white rot, the most destructive disease of these crops, caused by Sclerotium cepivorum, a pathogen restricted to Allium species. Presently, there are no single efficient control measures for white rot, but the evaluation of genetic resistance among Allium genotypes may help in disease management. In addition, little is kown on the variability of the pathogen in Brazil, which can be estimated indirectly by mycelial compatibililty testes. Therefor, this study aims to: (i) estimate the variability of a collection of S. cepivorum isolates from several Brazilian garlic and onion growing regions, and (ii) evaluate the reaction of garlic and onion genotypes to S. cepivorum in commercial growing field conditions. Initially, the identification of all S. cepivorum isolates was confirmed by the comparison of rDNA sequences. For the DNA analysis, genomic DNA was extracted and amplified with primers ITS1 and ITS4 for the ITS1, ITS2 and 5.8S ribossomic DNA regions. Subsequently fifity-two isolates from different geographical origins were selected for mycelial compatibility tests, and all isolates were confronted in all possible combinations. Two mycelial compatibility groups were identified. According to the compatibility test, the group of 52 isolates appeared to display low genotypic variability and was predominantly clonal. The reaction of Allium genoypes to white rot was evaluated in the field, in the 2016 and 2017 cropping seasons. Twenty garlic and 30 onion genotypes were evaluated in 2016, while, in 2017, 12 garlic and 30 onion genotypes were tested. Some genotypes tested in 2016 were repeated in 2017, as controls. Experiments were carried out at the Cooperativa Agropecuária do Alto Paranaíba – COOPADAP experimental fields, in Rio Paranaíba/MG, from May to September of 2016 and 2017. The fields selected for the assays were naturally infested with microesclerotia of S. cepivorum, from previous successive garlic and onion crops. Responses of garlic and onion genotypes to white rot varied. Among garlic genotypes, the ones that showed lowest degree of successibility and higher yields were UO 73, DDR 6024 and RAL 127. Among the onion genotypes, cvs. Optima F1, Sirius F1, Franciscana IPA10, Shinju F1 and Perfecta F1stood out as the genotypes with the lowest degree of successibility and greater yields. In the second experimental year, when disease levels were extremely high, associated to the prevailing lower temperatures, no differences among the genotypes were detected. From the overall field results, there are variations in the response of garlic and onion genotypes to white rot and good yields, that may be useful for disease management as well as in breeding programs.
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20

Santos, Inaura Patrícia da Silva. "Controle alternativo da podridão radicular (Sclerotium rolfsii Sacc.) em feijão-caupi [Vigna unguiculata (L.) Walp.] (Fabaceae)." Universidade Federal de Alagoas, 2010. http://repositorio.ufal.br/handle/riufal/250.

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The cowpea, Vigna unguiculata (L.) Walp., is known as feijão-de-corda and feijão-verde , among others, is one of the main cultures exploited by small producers of the Northeast region of Brazil. Among the phytopathogens that affects its productivity, Sclerotium rolfsii Sacc. is noteworthy, causing the stem rot in several cultures around the world. The objective of this work was to evaluate the alternative control of S. rolfsii Sacc. in saplings of V. unguiculata (L.) Walp. trough the biocontrol of antagonists, organic residues incorporation to the soil, utilization of essential oils, plant extracts and mineral nutrition. The work was developed in the Laboratory de Phytopathology and in the vegetation house of CECA/UFAL. The pathogen was obtained trough the isolations of cowpea with symptoms of the disease and, afterwards, it was cultivated in sterilized rice. For in vitro control, the antagonists isolates were matched with the pathogen in PDA medium, for the purpose of evaluating the reduction of growth and the hyperparasitism. For the biofumigations of the soil, the organic materials poultry litter, mussel, sugar cane bagasse, bean residue, cassava scuff were dehydrated in stove at 55ºC for 96h, grinded in the concentrations of 10% and 20% (v/v) and incorporated to the substrate, infested for 20 days and compared to the group treated with methyl thiophanate and to the control. After thirty days, the seedlings were evaluated about the incidence and the suppression of the disease. In the in vivo control the seeds were microbiolized with antagonists (C110, C21, ENF24, R14 and Trichoderma harzianum), the fungicide and saline solution for the control. The substrate was infested with the pathogen, two days after the sow, and after 30 days were evaluated. For the natural substances, 21 days old seedlings were pulverized with cassava flour wastewater extract (40%), eucalyptus oil (1%), peppermint (1%), Ecolife® (2%), methyl thiophanate (0,7 g/L) and water for the control and after two days, the substrate was infested with the pathogen. Six days after the inoculation, a new pulverization was done. The mineral fertilization was done in the sow trough Sarruge solution and doses of calcium silicate and sodium, 50, 100, 500 and 1000mg/L-1 and water for the control. The substrate was infested two days after that and a second fertilization was done 10 days after the sow. After 30 days the evaluations took place. The antagonists R14, C16, ENF 24 and T. harzianum inhibited the pathogen with RC from 42 up to 57%. Trichoderma has the hyperparasitic capacity. The incorporation of organic material was not efficient in the control of the disease. The in vivo antagonists reduced the incidence of the disease, but it was effective in the suppression. The oils and plant extracts were not efficient in reduced the incidence. The mineral fertilizations was not able to suppress the disease.
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O feijão-caupi, Vigna unguiculata (L.) Walp., é conhecido como feijão-de-corda e feijão-verde sendo uma das principais culturas exploradas pelos pequenos produtores no Nordeste brasileiro. Dentre os fitopatógenos que afetam sua produtividade, destaca-se Sclerotium rolfsii Sacc. que causa a podridão de colo em diversos cultivos do mundo. O objetivo do trabalho foi avaliar o controle alternativo de S. rolfsii Sacc. em mudas de V. unguiculata (L.) Walp. através do uso de antagonistas, incorporação de resíduos orgânicos ao solo, utilização de óleos essenciais, extratos vegetais e ecolife® e nutrição mineral. O trabalho foi desenvolvido no Laboratório de Fitopatologia e em casa de vegetação do CECA/UFAL. O patógeno foi obtido pelo isolamento de folhas de feijão-caupi com sintomas da doença e depois cultivados em arroz esterilizado. Para controle in vitro , os isolados de antagonistas foram pareados com o patógeno em meio de BDA, para avaliar a redução de crescimento micelial (RC) e o hiperparasitismo. Para a biofumigação do solo, as matérias orgânicas cama de frango, marisco, bagaço de cana, resíduo de feijão, raspa de mandioca foram desidratadas em estufa 55ºC por 96h, moídas e incorporadas ao substrato infestado, em concentrações de 10% e 20% (v/v) por 20 dias e comparadas ao tiofanato metílico e a testemunha. Após 30 dias, as plantas foram avaliadas quanto à incidência da doença e desenvolvimento da planta. No controle in vivo as sementes foram microbiolizadas com os antagonistas (C110, C21, ENF24, R14 e Trichoderma harzianum), o fungicida e água salina para testemunha. O substrato foi infestado com o patógeno, dois dias após o semeio foram avaliadas com 30 dias. Para as substâncias naturais, plantas de feijão-caupi, com 21 dias de idade foram pulverizadas com extrato de manipueira (40%), óleo de eucalipto (1%), hortelã pimenta (1%), Ecolife® (2%), tiofanato metílico (0,7 g/L) e água para a testemunha. Após dois dias, o substrato foi infestado com o patógeno. Ao completar seis dias da infestação, uma nova pulverização foi realizada. A adubação mineral foi realizada no semeio através de solução de Sarruge e doses de silicato de cálcio e sódio, 50, 100, 500 e 1000mg/L-1 e água para testemunha. O substrato foi infestado dois dias depois e uma segunda adubação foi feita 10 dias após o semeio. Os antagonistas R14, C16, ENF 24 e T. harzianum inibiram o patógeno com RC de 42 a 57%. Trichoderma teve capacidade hiperparasitária. A incorporação da matéria orgânica não foi eficiente no controle da doença. Os antagonistas in vivo reduziram a incidência da doença e contribuiu para o desenvolvimento das plantas. Os óleos e extratos vegetais não foram eficientes em reduzir a incidência da doença. A adubação mineral não foi capaz de suprimir a doença.
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Zibetti, Volnei Knopp. "Produção e qualidade biológica de húmus de minhoca para uso na supressão de Sclerotium rolfsii Sacc." Universidade Federal de Pelotas, 2013. http://repositorio.ufpel.edu.br/handle/ri/2370.

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The earthworm breeding corresponds to the creation of earthworm for different purposes like producing arrays and cocoons and worms for the production of vermicompost. The vermicompost, widely used as a fertilizer in agriculture and family farming systems ecologically based, also has important role as fitoprotetor. The study aimed to produce vermicompost of Eisenia andrei Bouché from cattle manure (CM) and combinations of this with peanut husk (PH), as structural materials, and spent coffee grounds (SCG), nutritional qualities of the source, and its evaluation in liquid and aerated form in suppressiveness Sclerotium rolfsii Sacc. The work was divided into two stages. At first, vermicompost produced up to four treatments and six replications: H1 CM 100%); H2 CM 75% + PH 25%; H3 CM 75% + SCG 25%; H4 CM 50% + SCG 25% + PH 25%. We evaluated the biomass of earthworms, cocoon production, yield and vermicompost microbiological and chemical variables. Treatments H3 and H4 had higher biomass and cocoon production. When assessed the density of bacterial colonies and fungal treatments H2 and H4 registered the highest rates. In the second step, vermicompost tea aerated were prepared from different combinations of vermicompost, in order to test their antagonistic effect against S. rolfsii. The vermicompost were packed in sachets and immersed in water and aerated for a period of 24 hours. Were quantified bacterial and fungal colonies present in vermicompost tea (VT), in selective culture media. Representative samples of VT obtained from each of the four treatments were evaluated on mycelial growth of S. rolfsii from mycelium and sclerotic under two conditions: unfiltered and filtered. The VT filtered did not inhibit mycelial growth of S. rolfsii, as opposed to VT unfiltered. Colonies of microorganisms coming from the unfiltered treatments, once isolated and purified, were paired with discs of mycelium of S. rolfsii, to evaluate the effect of antagonistic fungi and bacteria present in vermicompost on the sclerotic. The F3 isolated, on VT on treatment H2, identified as belonging to the genus Trichoderma, was the one who showed the greatest inhibition to S. rolfsii, among other microorganisms matched. The production and use of vermicompost in family farming should be encouraged, because besides the already established benefits of fertilization on cropping systems can also aid in the control of plant diseases.
A minhocultura corresponde à criação de minhocas destinadas a diferentes fins, como produção de matrizes e casulos, e minhocas destinadas a produção de húmus. O húmus de minhoca, amplamente utilizado como fertilizante na agricultura familiar e sistemas agrícolas de base ecológica, também tem relevante papel como fitoprotetor. O estudo teve por objetivo produzir húmus de minhoca da espécie Eisenia andrei Bouché a partir de esterco bovino (EB) e combinações deste com cascas de amendoim (CA), como material estruturante, e borra de café (BC), na qualidade de fonte nutricional, e sua avaliação na forma líquida e aerada na supressividade de Sclerotium rolfsii Sacc. O trabalho foi dividido em duas etapas. Na primeira, produziu-se húmus em quatro tratamentos e seis repetições, sendo: H1 EB 100%; H2 EB 75% + CA 25%; H3 EB 75% + BC 25%; H4 EB 50% + BC 25% + CA 25%. Avaliou-se a biomassa de minhocas, produção de casulos, rendimento de húmus e variáveis microbiológicas e químicas. Os tratamentos H3 e H4 apresentaram maiores índices de biomassa e produção de casulos. Quando avaliadas as densidades de colônias bacterianas e fúngicas, os tratamentos H2 e H4 registraram os maiores índices. Na segunda etapa, foram preparados húmus líquidos aerados a partir das diferentes combinações de húmus, com o objetivo de testar seus efeitos sobre escleródios de S. rolfsii. Os húmus foram acondicionados em sachês e mergulhados em água, sendo aerados pelo período de 24 horas. Foram quantificadas as colônias bacterianas e fúngicas presentes nos húmus líquidos (HL), em meios de cultura seletivos. Amostras representativas de HL obtidos de cada um dos quatro tratamentos foram avaliadas no crescimento micelial de S. rolfsii, a partir de micélio e escleródio, em duas condições: filtradas e não filtradas. Os HL filtrados não inibiram o crescimento micelial de S. rolfsii, em oposição aos HL não filtrados. As colônias de microrganismos oriundas dos tratamentos não filtrados, uma vez isoladas e purificadas, foram pareadas com discos de micélio de S. rolfsii, objetivando avaliar o efeito antagônico de fungos e bactérias presentes nos húmus sobre o escleródio. O isolado F3, do HL oriundo do tratamento H2, identificado como pertencente ao gênero Trichoderma, foi quem apresentou a maior inibição ao S. rolfsii, dentre os demais microrganismos pareados. A produção e o uso de húmus de minhoca na agricultura familiar devem ser estimulados, pois além dos benefícios já consagrados acerca da fertilização em sistemas de cultivo também podem auxiliar no controle de doenças de plantas.
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22

Glue, Joshua Barnaby. "Engineering Allium White Rot Disease Resistance in Allium Species and Tobacco Model Species." Thesis, University of Canterbury. School of Biological Sciences, 2009. http://hdl.handle.net/10092/3513.

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Allium white rot (AWR) is a soilborne disease that seriously damages commercial cultivation of onion (Allium cepa) and garlic (Allium sativum) crops. The disease has been found everywhere onions are cultivated and at present no system of control has been found that fully prevents the occurrence of the disease. The fungus responsible for the disease, Sclerotium cepivorum, uses oxalic acid to kill Allium bulb and root tissue in growing onion and garlic plants. Research suggests recombinant oxalate oxidase and oxalate decarboxylase enzymes may be able to degrade this acid and confer resistance against pathogens that rely on it, such as Sm. cepivorum or Sclerotinia sclerotiorum. To test the efficacy of these enzymes against white rot pathogens, three transgenes for wheat oxalate oxidase, barley oxalate oxidase and Flammulina oxalate decarboxylase were transformed into onions and garlic by Agrobacterium-mediated transformation. Allium species are highly recalcitrant to transformation, so these three transgenes were also transformed into tobacco to provide fast-recovering, easy to test transformants to assess the efficacy of the transgenes. Transformed garlic and tobacco lines were analysed to assess the integration and expression of the transgenes, then challenged with Sm. cepivorum or Sa. sclerotiorum, respectively, to assess the bioactivity of recombinant wheat oxalate oxidase, barley oxalate oxidase, and Flammulina oxalate decarboxylase against oxalic acid-dependent pathogens. Results show that one line of tobacco expressing the Flammulina oxalate decarboxylase enzyme was found to be consistently resistant to Sclerotinia sclerotiorum. Garlic lines transformed with this transgene failed to display stable transgene expression or disease resistance, possibly due to silencing of the transgene in recovered transformant tissue.
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Reis, Marcella Teles dos. "Identificação e avaliação do potencial de uso de isolados de Trichoderma contra Sclerotinia sclerotiorum e Sclerotium rolfsii." reponame:Repositório Institucional da UnB, 2014. http://repositorio.unb.br/handle/10482/18173.

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Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Fitopatologia, Programa de Pós-Graduação em Fitopatologia, 2014.
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O Brasil se destaca no cenário mundial como um dos principais produtores de feijão. Entretanto, vários problemas fitossanitários contribuem para redução da renda líquida auferida na exploração da cultura, entre os quais, o mofo branco e a podridão de escleródio, causadas pelos fungos Sclerotinia sclerotiorum (SS) e Sclerotium rolfsii (SR), respectivamente, reconhecidas como principais doenças do feijão. O controle biológico, pelo uso de Trichoderma tem sido proposto como um dos métodos de manejo das doenças. Espécies desse gênero possuem grande importância agronômica e atuam como decompositores primários de matéria orgânica, destacando-se também pela produção de metabólitos e enzimas com propriedades antifúngicas. Em face disso, o trabalho foi conduzido com o objetivo de identificar isolados de Trichoderma com potencial de uso contra SS e SR. Cento e quarenta e nove isolados foram testados in vitro e 50 destes foram pré-selecionados e identificados com base no seqüenciamento das regiões ITS e TEF do rDNA. Dentre esses, foram identificadas sete espécies do gênero Trichoderma: T. harzianum, T. stromaticum, T. koningiopsis, T. asperellum, T. tomentosum, T. spirale e T. erinaceum. Vinte isolados foram testados em casa de vegetação. Resultados desse estudo mostram que, in vitro, 10,6% dos isolados testados contra SS e 14% contra SR apresentaram nota 1 no pareamento de cultura; 15,33% dos isolados para SS e 4,6% para SR mostram níveis elevados de antagonismo quanto a inibição micelial do patógeno por metabólitos não-voláteis. Dos 20 isolados selecionados para os estudos em casa de vegetação, quatro se destacaram: CEN207 (T. koningiopsis), CEN188 (T. spirale), CEN200 (T. koningiopsis) e CEN189 (T. spirale) sobre os demais quanto a promoção de crescimento. A técnica de identificação por MALDI TOF MS foi utilizada com oito dos isolados de Trichoderma previamente identificados com base no sequenciamento de fragmentos do DNA, agrupando-se de acordo com as espécies, conforme o esperado e formando clados no dendograma. Metabólito bruto extraído do isolado CEN277 (T. asperellum) foi analisado em HPLC e mostrou grande potencial quanto à inibição do crescimento micelial de S. sclerotiorum. As técnicas utilizadas com cromatografia líquida e MALDI TOF MS, embora iniciais, proporcionaram resultados interessantes e necessitam de mais dedicação para a obtenção de resultados conclusivos na identificação das moléculas envolvidas. ______________________________________________________________________________________________ ABSTRACT
Brazil stands out in the global scenario as one the leading producers of beans. However, many phytossanitary problems contribute to a reduction of yield, including white mold and sclerotia rot, caused by the fungi Sclerotinia sclerotiorum (SS) and Sclerotium rolfsii (SR) respectively, whith are recognized as major bean diseases. Biological control using Trichoderma has been proposed as a method of managing these diseases. Species of this genus are, of great agronomic interest and act as primary decomposers of organic material and are, also highlighted by the production of enzymes and metabolites with antifungal properties. For this reason, this study was conducted in order to identify Trichoderma isolates able to implement the biocontrol of these diseases. One hundred forty-nine isolates were tested in vitro and 50 of these were pre-selected and identified based on sequencing of the TEF and ITS regions of rDNA. Seven species of Trichoderma have been identified based on molecular characterization: T. harzianum, T. stromaticum, T. koningiopsis, T. asperellum, T. tomentosum, T. spirale and T. erinaceum. Among fifty isolates, 20 were tested under greenhouse conditions. Results of this study show that, in vitro, 10.6% of the isolates tested against SS and 14% against SR reached note 1 in paired culture; 15.33% of the isolates for SS and 4.6% for SR show elevated levels of antagonism regarding pathogen mycelial inhibition by non-volatile metabolits. From 20 isolates selected for studies under greenhouse conditions, four stood out compared to others, as promoting growth: CEN207 (T. koningiopsis), CEN188 (T. spirale), CEN200 (T. koningiopsis) and CEN189 (T. spirale). The technique of identification by MALDI TOF MS was used with eight isolates of Trichoderma previously identified based on DNA sequencing, grouped according to the species, as expected forming a clade on the dendrogram. Crude metabolite extracted from the CEN277 (T. asperellum) was analyzed by HPLC and showed great potential for the inhibition of mycelial growth of S. sclerotiorum. The techniques used in liquid chromatography and MALDI TOF MS, although preliminars, have provided interesting results and motivate further studies to identils the involved molecule.
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24

Volpiano, Camila Gazolla. "Rhizobium spp. para o controle biológico do fungo fitopatogênico Sclerotium (Athelia) rolfsii no feijoeiro (Phaseolus vulgaris L.)." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/180739.

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Rizóbios são bactérias fixadoras de nitrogênio utilizadas com sucesso como inoculante microbiano para diminuir a utilização de fertilizantes nitrogenados no cultivo do feijoeiro (Phaseolus vulgaris L.) e outras leguminosas. Sclerotium rolfsii (sin. Athelia rolfsii) é um fungo onipresente que causa perdas severas em culturas importantes, inclusive em espécies de Phaseolus. Assim, o objetivo deste estudo foi avaliar a coleção de Rhizobium SEMIA para identificar o primeiro agente rizobial para o biocontrole da doença promovida por S. rolfsii no feijoeiro. Duplas culturas foram primeiramente realizadas para identificar propriedades de biocontrole entre as estirpes. Entre as 151 estirpes SEMIA testadas, 33 (~22%) mostraram atividade antagonista, sendo 16 delas capazes de % do crescimento micelial. As estirpes antagonistas produziram de 1,2 a 36,5 -1 de ácido indol-acético (IAA), um fitohormônio mais conhecido por promover o crescimento de plantas do que por inibir diretamente patógenos. Contudo, obteve-se um r=0,447 (p=0,011) entre a produção de IAA das estirpes antagonistas e a capacidade de inibição do micélio. As estirpes SEMIA 436, 4077, 4088 e 460 foram produtoras de sideróforos, e a atividade antagonista de SEMIA 4088 pode ser, em parte, relacionada a isso. Além de compostos antimicrobianos difusíveis no meio de cultura, SEMIA 460 também inibiu 45% do crescimento micelial através da produção de compostos voláteis. A análise do 16S rRNA possibilitou a identificação das estirpes SEMIA 456, 4026, 436, 439, 4032, 460, 4085, 4080, 4077 e 4088 como Rhizobium spp. Considerando o alto grau de conservação do 16S rRNA dentro do gênero Rhizobium, as linhagens SEMIA 436 e 439 apresentaram similaridades menores que 98,65% com o banco de dados, possivelmente representando um novo táxon. Apesar de terem sido isoladas de nódulos de feijão, as estirpes SEMIA 436, 439, 456, 4026 e 4032 foram alocadas em um ramo filogenético com estirpes de Rhizobium tumorigênicas (agrobacteria). Finalmente, para testar a eficiência de biocontrole das estirpes antagonistas selecionadas, plantas de feijão foram individualmente inoculadas e cultivadas em vasos com solo infectado com S. rolfsii. Para os parâmetros i) porcentagem de doença e ii) massas secas da parte área os tratamentos com SEMIA 4032, 4077, 4088, 4080, 4085 ou 439 não apresentaram diferenças estatisticamente significativas quando comparadas com o controle (plantas de feijão cultivadas em solo não infectado), demonstrando a grande potencialidade destas estirpes no controle biológico de S. rolfsii mediante inoculação de sementes de feijão.
Rhizobia are nitrogen-fixing bacteria successfully used as microbial inoculant attempting to diminish synthetic nitrogen fertilizers inputs on the common bean (Phaseolus vulgaris L.) and others legume crops. Sclerotium rolfsii (syn. Athelia rolfsii) is a ubiquitous fungus that causes several losses on important crops, including Phaseolus species. In this way, the aim of this study was to evaluate SEMIA Rhizobium Culture Collection to identify the first rhizobial biocontrol agent for the S. rolfsii-promoted disease on the common bean. Dual cultures were first performed to screening strains for biocontrol proprieties. Among of the 151 SEMIA strains, 33 (~22%) of them showed antagonistic activity on dual cultures % of mycelial growth. Antagonistic -1 of indole-acetic acid (IAA), a phytohormone best known to promote plant growth than to direct inhibit plant pathogens. However, a r=0.447 (p=0.011) was obtained between antagonistic strains IAA production and mycelium inhibition ability. Strains SEMIA 436, 4077, 4088 and 460 were siderophore producers, and SEMIA 4088 antagonistic activity can be related to this. Besides antimicrobial diffusible compounds, SEMIA 460 inhibited 45% of mycelial growth through volatiles compounds production. Analysis of 16S rRNA identified strains SEMIA 456, 4026, 436, 439, 4032, 460, 4085, 4080, 4077 and 4088 as Rhizobium spp. Considering the high degree of 16S rRNA conservation in Rhizobium genus. SEMIA 436 and 439 were found to represent new taxa for presenting gene similarities less than 98.65% with the database. Despite being isolated from nodules, SEMIA 436, 439, 456, 4026 and 4032 were placed in a phylogenetic branch with tumorigenic Rhizobium (agrobacteria). Finally, to evaluate biocontrol efficiency of the selected antagonists strains, common bean plants were individually inoculated and grown in pots with S. rolfsii infected soil. For the parameters i) disease percentage and ii) shoot dry masses, treatments with SEMIA 4032, 4077, 4088, 4080, 4085 and 439 were not found with statistically significant differences from the control (plants grown on uninfected soil), demonstrating the great potentiality of these strains for biological control of S. rolfsii through inoculation of common bean seeds.
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25

Kwong, S. M. "In-vitro study of the bonding of a self-etching primer to noncarious sclerotic cervical dentine." Click to view the E-thesis via HKUTO, 2000. http://sunzi.lib.hku.hk/HKUTO/record/B38628235.

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26

鄺社滿 and S. M. Kwong. "In-vitro study of the bonding of a self-etching primer to noncarious sclerotic cervical dentine." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B38628235.

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27

Pacheco, Klênia Rodrigues. "Avaliação de Trichoderma e de fosfito no controle da murcha-de-esclerócio em feijoeiro causada por Sclerotium rolfsii." reponame:Repositório Institucional da UnB, 2012. http://repositorio.unb.br/handle/10482/11184.

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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Agronomia e Medicina Veterinária, Programa de Pós-Graduação em Agronomia, 2012.
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O feijoeiro (Phaseolus vulgaris) é suscetível a muitas doenças, entre elas, se encontra a murcha-de-esclerócio (podridão do colo) causada por Sclerotium rolfsii. O controle do S. rolfsii ocorre com o auxílio de práticas preventivas e por controle biológico ou químico. O estudo teve como objetivo selecionar e testar isolados de Trichoderma oriundos de solos do DF, avaliar e comparar os Trichoderma spp. selecionados e fosfitos (Cu, Ca, Mg e K) aos fungicidas no controle da murcha-de-esclerócio. Nos ensaios realizados foram utilizados dois isolados de S. rolfsii (UB 193 e UB 228). Dos 65 isolados de Trichoderma testados in vitro selecionaram-se os seguintes: 5, 11, 12, 15, 102, 103, 127, 136, 137, 1525, 1637, 1642, 1643, 1649, 1700 e EST 5. Esses isolados de Trichoderma, bem como os fosfitos [Fosfito: Cu (25% P2O5 + 5% Cu); K1 (40% P2O5 + 20% K2O); Mg1 (30% P2O5 + 4% Mg); Ca1 (30% P2O5 + 7% Ca); Ca2 (10% P2O5 + 6% Ca); K2 (40% P2O5 + 20% K2O); K3 (20% P2O5 + 20% K2O); K4 (30% P2O5 + 20% K2O); K5 (27% P2O5 + 27% K2O)] e fungicidas [Tebuconazol (250 g/L); Tiofanato-Metílico (500 g/L); Procimidona (500 g/kg); Carbendazim (500 g/kg)] foram avaliados quanto ao efeito sobre a germinação de esclerócios do patógeno em laboratório e sobre a doença em casa de vegetação. Os isolados de Trichoderma 1649, 1525 e 1637 foram os mais eficientes na inibição da germinação de esclerócios de S. rolfsii em laboratório. Além disso, os isolados 5, 12, 102, 103, 1525 e 1649 foram eficientes na melhoria do número de plantas sadias de feijoeiro em casa de vegetação. Dos testes realizados com fosfitos, as formulações com Potássio (K2) e Cálcio (Ca1) controlaram o patógeno no teste em casa de vegetação. Dos agentes químicos testados, o produto que reduziu significativamente a doença foi o Tebuconazol. _________________________________________________________________________________ ABSTRACT
Phaseolus vulgaris (Common bean) is susceptible to several diseases, among them there is the sclerotium wilt, also known as stem rot caused by Sclerotium rolfsii. The control of the disease could be throughout preventive practices or by biological or chemical control. This study was carried out to evaluate the effects of Trichoderma spp., phosphites (Cu, Ca, Mg, and K) and traditional fungicides to control sclerotium wilt of common bean. The experiments were performed with two isolates of S. rolfsii (UB 193 and UB 228). Sixty-five Trichoderma isolates were tested in vitro for inhibition of S. rolfsii, and the following ones were selected: 5, 11, 12, 15, 102, 103, 127, 136, 137, 1525, 1637, 1642, 1643, 1649, 1700 and EST 5. These selected Trichoderma, phosphites [Phosphite: Cu (25% P2O5 + 5% Cu); K1 (40% P2O5 + 20% K2O); Mg1 (30% P2O5 + 4% Mg); Ca1 (30% P2O5 + 7% Ca); Ca2 (10% P2O5 + 6% Ca); K2 (40% P2O5 + 20% K2O); K3 (20% P2O5 + 20% K2O); K4 (30% P2O5 + 20% K2O); K5 (27% P2O5 + 27% K2O)] and fungicides [Tebuconazole (250 g/L); Methyl Thiophanate (500 g/L); Procymidone (500 g/kg); Carbendazim ( 500 g/kg)] were tested for evaluation of sclerotial germination under laboratory conditions, and to evaluate the effects on disease of bean plants under greenhouse conditions. The Trichoderma isolates 1649, 1525 and 1637 were more efficient in reducing sclerotial germination. In addition, the isolates 5, 12, 102, 103, 1525 e 1649 significantly improved the number of non-diseased plants under greenhouse conditions. Phosphites of K (K2) and Ca (Ca1) inhibited sclerotial germination in laboratory and reduced disease in plants grown in greenhouse. Tebuconazole was the product that significantly reduced disease severity on bean under greenhouse condition.
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28

Hutchins, John David. "Antagonism of the stem rot pathogen (Sclerotina sclerotiorum) by microorganisms from oilseed rape flowers : prospects for biological control." Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281747.

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29

Soares, João Vitor Camargo. "Manejo da murcha de esclerócio (Sclerotium rolfsii Sacc) em pimentão e seleção de acessos de Capsicum Sp. Resistentes." Universidade Federal do Amazonas, 2013. http://tede.ufam.edu.br/handle/tede/4677.

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BASA - Banco da Amazônia
The sclerotium wilt, caused by the fungus Sclerotium rolfsii Sacc. is a difficult disease to control, causing high losses in crops and chili peppers in the State of Amazonas and fundamental knowledge of the pathogen, for the establishment of disease management strategies and provide support for studies of resistance. This work aimed at evaluating the resistance of 20 genotypes of Capsicum sp to isolate, and performed a pretest aggressively ten isolates from different localities. We also evaluated the effect of Silicon, Glyphosate and nettle extract on the mycelial growth of the pathogen in vitro and in vivo. To assess aggression used the isolated IRB02 and experimental design in factorial randomized block with three replicates 1x20, containing a plant inoculated with three disks of mycelium of the pathogen witnesses absent from each genotype containing pathogen. In evaluating the effect of Si, Gliz and extract the design was completely randomized in a factorial 1x3x3, evaluating the Index mycelial growth in vitro with ten replicates, acada board an experimental unit, and a control containing only PDA medium for growth pathogen. To evaluate the effect of Si, and Gliz Extract in greenhouse was used in a completely randomized factorial 2x3x4 with five replicates, each constituted by a plant and the witnesses containing plants without application of products and evaluated the incidence and severity of disease for 30 days. Data were subjected to analysis of variance and means were compared by Tukey test at 5% probability using the program ASSISTAT 7.6 Beta. The isolated IR02 showed more aggressiveness average, being selected for the remaining stages of the study. Genotypes BC16, MA34; ATN01; ATN02; MA03; LA02; TBT01; MA18, MA43; BC01; ATN04; MA31; IRB02 showed greater resistance to the pathogen under study. The sources of Si 15.0 and 24.0 g / L-1, Gliz 4.0 mL / L-1 and Nettle Extract 10%, 20% and 50% used in the experiment had to be efficient in controlling the pathogen in vitro. These same sources were effective against the pathogen in the farming and Nathalie Tiberius in all volumes used, compared to the control. Given the results obtained, the isolated IRB02 can be used to assess the genotype resistance of Capsicum sp. The genotypes showed that resistance to the pathogen present with potential for studies of breeding and chili peppers for resistance to the pathogen under study and the products used can be better evaluated in relation to the volume to be used for possible disease control crops of peppers and chili.
A murcha de esclerócio, causada pelo fungo Sclerotium rolfsii Sacc. é uma doença de difícil controle, ocasionando elevadas perdas em cultivos de pimentas e pimentão no Estado do Amazonas, sendo fundamental o conhecimento do patógeno, visando o estabelecimento de estratégias de manejo da doença e fornecer subsídios para estudos de resistência. Este trabalho objetivou-se em avaliar a resistência de 20 genótipos de Capsicum sp ao isolado, sendo realizado um pré teste de agressividade com dez isolados provenientes de diferentes localidades. Avaliou-se também o efeito de Silicio, Glifosato e Extrato de urtiga sobre o crescimento micelial do patógeno in vitro e in vivo. Para avaliar agressividade utilizou-se o isolado IRB02 e delineamento experimental em blocos ao acaso em fatorial 1x20 com três repetições, contendo uma planta inoculada com três discos de micélio do patógeno a as testemunhas contendo cada genótipo ausente de patógeno. Na avaliação do efeito de Si, Gliz e Extrato o delineamento foi inteiramente casualisado em fatorial 1x3x3, avaliando-se o Indice de crescimento micelial in vitro com dez repetições, sendo cada placa uma unidade experimental, e a testemunha contendo apenas meio BDA para o crescimento do patógeno. Para a avaliação do efeito de Si, Gliz e Extrato em casa de vegetação, utilizou-se delineamento inteiramente casualisado em fatorial 2x3x4 com cinco repetições, constituída por uma planta cada e as testemunhas contendo plantas sem aplicação dos produtos, sendo avaliadas incidência e severidade da doença durante 30 dias. Os dados obtidos foram submetidos à análise de variância e as médias comparadas pelo teste de Scott-Knott ao nível de 5% de probabilidade utilizando o programa ASSISTAT 7.6 Beta. O isolado IRO2 apresentou maior agressividade média, sendo selecionado para as demais etapas do estudo. Os genótipos BC16; MA34; ATN01; ATN02; MA03; LA02; TBT01; MA18; MA43; BC01; ATN04; MA31; IRB02 apresentaram maior resistência ao patógeno em estudo. As fontes de Si 15,0 e 24,0 g / L-1, Gliz 4,0 mL / L-1 e Extrato de urtiga 10%, 20% e 50% utilizadas no experimento apresentaram-se eficientes no controle do patógeno in vitro. Estas mesmas fontes foram eficientes sobre o patógeno na cultivar Nathalie e Tibérius em todos volumes utilizados,comparados a testemunha. Diante aos resultados obtidos, o isolado IRB02 pode ser utilizado para avaliar a resistência de genótipos de Capsicum sp. Os genótipos que demonstraram resistência ao patógeno apresentam-se com potencial para estudos de melhoramento genético de pimentas e pimentão quanto à resistência ao patógeno em estudo e os produtos utilizados podem ser melhor avaliados em relação ao volume a ser utilizado, para possível controle da doença em cultivos de pimentas e pimentão.
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30

Sousa, Thiago Gomes de. "Controle da podridão por sclerotium rolfsii em alho (Allium sativum L.) e cebola (Allium cepa L.) por trichoderma." reponame:Repositório Institucional da UnB, 2012. http://repositorio.unb.br/handle/10482/10741.

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Dissertação (mestrado)—Universidade de Brasília, Programa de Pós-Graduação em Agronomia, 2012.
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A podridão por esclerócio (Sclerotium rolfsii) está entre as doenças mais importantes do alho (Allium sativum) e da cebola (A. cepa). Em países de clima frio há relatos de perdas entre 10% a 65%, enquanto em países de clima tropical estas perdas podem atingir 100%. O patógeno tem uma ampla gama de hospedeiros, sendo capaz de infectar mais de 500 espécies vegetais. O fungo se propaga por estruturas de resistência, esclerócios, que podem sobreviver por vários anos no solo, além de serem facilmente levadas pela água e movimentação de pessoas e equipamentos. Alguns métodos de controle têm sido relatados contra a doença, por exemplo: o químico por meio de fungicidas (tebuconazole, thiram, procimidone), o físico com solarização (cobertura do solo com lonas e coletores solares), o cultural por meio da adição de matéria orgânica que promove o aumento da população dos microorganismos benéficos e o biológico com a inoculação de organismos antagônicos aos patógenos. Há necessidade de melhoria do manejo da doença, devido à dificuldade de controle do patógeno e o interesse ambiental de diminuição a cada dia da utilização de produtos químicos. Assim, o objetivo principal neste estudo foi avaliar produtos comerciais à base de Trichoderma no controle da podridão do alho e cebola. Primeiramente, foi avaliada a eficiência de T. harzianum comercial em relação a fungicidas (procimidona e tiofanato metílico) por teste de germinação de esclerócios (solo em caixas plásticas) em laboratório e por teste in vivo com plantas de alho em casa de vegetação. Em uma segunda parte do estudo foi avaliado a eficiência de T. harzianum e T. asperellum em campo experimental de cebola inoculado artificialmente com S. rolfsii. Em todos os trabalhos os produtos à base de Trichoderma foram superiores aos fungicidas. Nos testes in vivo com plantas de alho observou-se (a) um menor número de plantas infectadas, (b) aumento de massa seca de raiz e parte aérea em relação à testemunha com patógeno, e; (c) menor número de esclerócios capturados nos tratamentos com T. harzianum. Nos campos experimentais de cebola o tratamento Sclerotium rolfsii + T. harzianum apresentou a menor incidência, diferindo significativamente da testemunha com patógeno. No tratamento somente com T. harzianum houve o maior ganho de produtividade em relação à testemunha somente com patógeno. O tratamento com T. asperellum também reduziu a incidência da doença e induziu ganho em produtividade da cebola. ______________________________________________________________________________ ABSTRACT
The Sclerotium rot (Sclerotium rolfsii) is one of the most important diseases of garlic (Allium sativum) and onion (A. cepa). In cold climate countries losses between 10% to 65%, while in tropical countries, these losses can reach 100%. The pathogen has an extensive host range and is capable of infecting more than 500 species of plants. The fungus is spread by resistance structures, sclerotia, which can survive in soil for years, and are easily moved by wind, water and movement of people and equipment. Some methods of control have been reported against the disease, for example: the chemical by fungicides (tebuconazole, thiram, procymidone), the physical with solarization (soil covered with tarpaulins and solar panels), the culture by the addition of organic matter promoted the increase of the population of beneficial microorganisms and inoculation with biological organisms antagonistic to pathogens. There is need for improved management of the disease, due to the difficulty of controlling the pathogen and environmental interest of reduction day by day use of chemicals, thus the main objective of this study was to evaluate commercial products based on Trichoderma. First, we evaluated the efficacy of T. harzianum in relation to commercial fungicides (procymidone and thiophanate methyl) per test germination of sclerotia (soil in plastic boxes) in the laboratory and tested in vivo with garlic plants in the greenhouse. In a second part of the study was evaluated the efficacy of T. harzianum and T.asperellum onion trial field artificially inoculated with S. rolfsii. In all studies based products of Trichoderma were higher than fungicides. In vivo tests with garlic plants was observed (a) a lower number of infected plants, (b) increase in dry weight of roots and shoots compared to control with the pathogen, and (c) captured fewer sclerotia in treatments with T. harzianum. In onion trials field of treatment Sclerotium rolfsii + T. harzianum had the lowest incidence, differing significantly from the control with the pathogen. In the treatment only with T. harzianum was the largest productivity gain compared to control only with the pathogen. Treatment with T. asperellum also reduced the incidence of the disease and led to higher productivity of the onion. Key word: Allium sativum, Allium cepa, Sclerotium rolfsii, Trichoderma, biological control.
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31

Laborda, Laysa de Paiva. "Incorporação de fabáceas ao substrato de plantio para controle da podridão-de-escleródio (Sclerotium rolfsii Sacc.) em cubiu (Solanum sessiliflorum Dunal)." Instituto Nacional de Pesquisas da Amazônia, 2017. http://bdtd.inpa.gov.br/handle/tede/2468.

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Fundação de Amparo à Pesquisa do Estado do Amazonas - FAPEAM
Cubiu (Solanum sessiliflorum Dunal) cultivation in the Amazonas state is limited by the high incidence of southern blight caused by the soilborne fungus Sclerotium rolfsii Sacc. The incorporation of plant material into the substrate changes the microflora present by increasing the organic matter content and by the plants decomposition exudates, which may be toxic or beneficial to the different microorganisms present on the substrate. The incorporated organic matter also increases the nutrient content available to the plant. The objective of this study was to evaluate the potential for control of southern blight by the incorporation of fresh comminuted biomass of four Fabaceae species: Erythrina fusca and Senna reticulata, native to Amazonia, and Desmodium heterocarpon and Gliricidia sepium, exotic to the substrate. The isolate of S. rolfsii was obtained from cubiu plants with disease symptoms and multiplied in autoclaved rice. Infestation of the substrate (argisol: chicken manure, 2: 1) was done with the incorporation of 10 g of colonized rice.L-1, in pots filled with 8 L of substrate, kept in a nursery. After 20 days of infestation, were incorporated 40 g of the Fabaceae biomass.L-1 substrate. The cubiu seedlings, 90 days after sowing, were transplanted one week after the incorporation of the Fabaceae. The experimental design was completely randomized, with three replicates and seven treatments: four species of Fabaceae and three controls, without the incorporation of biomass. In one control the substrate was not infested and in other, the plants were sprayed (9 mL.plant-1) twice, 50 days apart, with fungicide (Viper 700®, methyl thiophanate, 0.49 g a.i. for litter of water). Another experiment was carried out to evaluate the effect of doses of G. sepium incorporated into the substrate. The experiment had a completely randomized design and three replicates, with six treatments: incorporation of 40, 80, 120 and 160 g of G. sepium.L-1 substrate and two controls without incorporation of G. sepium. In one control, the plants were treated with fungicide. In this experiment, the pots were filled with 6 L of substrate infested as described in the previous experiment. In both experiments the disease and the inoculum incidence in the substrate were evaluated. In the first experiment, the data from the area below the disease progress curve were submitted to ANOVA and the means, compared by the Tukey test. In the second experiment, the data were submitted to regression analysis. In the first experiment the cubiu plants cultived in substrate with Fabaceae incorporation or treated with fungicide had the same southern blight incidence and in the pathogen suppression. In the second experiment, the incidence of southern blight was proportional to the G. sepium dose incorporated. With the incorporation of 139 g of G. sepium.L-1 no diseased plants were observed. Also the incorporation of 142 g G. sepium.L-1 substrate reduced the population of S. rolfsii in the substrate by 20%.
O cultivo do cubiu (Solanum sessiliflorum Dunal), no Amazonas, é limitado pela alta incidência da doença podridão-de-escleródio causada por Sclerotium rolfsii Sacc. A incorporação de material vegetal ao substrato de cultivo altera a microflora presente nesse substrato, tanto pelo aumento do teor de matéria orgânica, quanto pela liberação de substâncias, durante a decomposição desse material vegetal, que podem ser tóxicas, ou benéficas, a diferentes microrganismos presentes no substrato. A matéria orgânica incorporada aumenta, também, o teor de nutrientes disponíveis para a planta. O trabalho objetivou avaliar o potencial de controle da podridão-de-escleródio em cubiu por meio de incorporação, ao substrato de cultivo, de biomassa fresca triturada de quatro espécies de fabáceas: Erythrina fusca e Senna reticulata, nativas da Amazônia, e Desmodium heterocarpon e Gliricidia sepium, exóticas. O isolado de S rolfsii foi obtido de plantas de cubiu com sintomas da doença e multiplicado em arroz autoclavado. A infestação do substrato (argissolo: esterco de galinha, 2:1 ) foi feita com a incorporação de 10 g de arroz colonizado.L- 1 de substrato, em vasos preenchidos com 8 L de substrato, mantidos em viveiro. Após 20 dias da infestação, foram incorporadas 40 g da biomassa das fabáceas.L-1 de substrato. As mudas de cubiu, aos 90 dias da semeadura, foram transplantadas para os vasos uma semana depois da incorporação das fabáceas. O delineamento experimental foi inteiramente casualizado, com três repetições e sete tratamentos: quatro espécies de fabáceas e três testemunhas, sem a incorporação de biomassa. Em uma das testemunhas não houve infestação do substrato e em duas, o substrato foi infestado, sendo que em uma, as plantas foram pulverizadas (9 mL.planta-1) duas vezes, com intervalo de 50 dias, com fungicida (Viper 700®, tiofanato metílico, 0,49 g do i.a.L-1 de água). Outro experimento foi realizado avaliando-se o efeito de doses de G. sepium incorporadas ao substrato. O experimento teve delineamento inteiramente casualizado e três repetições, com seis tratamentos: incorporação de 40, 80, 120 e 160 g de G. sepium.L-1 de substrato e duas testemunhas sem incorporação de G. sepium sendo que em uma, as plantas foram tratadas com fungicida. Neste, os vasos tiveram 6 L de substrato infestado com a mesma dosagem de inóculo do experimento anterior. Em ambos os experimentos foi avaliada a incidência da doença e a densidade do inóculo no substrato. No primeiro experimento, os dados da área abaixo da curva de progresso da doença foram submetidos à ANOVA e as médias, comparadas pelo teste Tukey. No segundo experimento os dados foram submetidos à análise de regressão. No primeiro experimento as fabáceas não diferiram do fungicida na redução da incidência da podridão-de-escleródio e na supressão do patógeno. No segundo experimento, a redução da incidência da podridão-de-escleródio foi proporcional ao aumento da dose de G. sepium, apresentando 100% de controle com a incorporação de 139 g de G. sepium.L-1 de substrato. A dose de 142 g reduziu a população de S. rolfsii no substrato em 20%.
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32

Bueno, César Júnior. "Produção e preservação de estruturas de resistência de fungos fitopatogênicos habitantes do solo /." Botucatu : [s.n.], 2004. http://hdl.handle.net/11449/105441.

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Orientador: Nilson Luiz de Souza
Banca: Edson Luiz Furtado
Banca: Yodiro Masuda
Banca: Raquel Ghini
Banca: Walmir Contra de Jesus Junior
Resumo: Os fungos fitopatogênicos habitantes de solo causam grandes perdas em culturas econômicas. Estes organismos, por produzirem estruturas de resistência na ausência de hospedeiros e/ ou condições climáticas desfavoráveis, inviabilizam o controle do patógeno. A preservação de fungos por longos períodos é importante para que pesquisas possam ser realizadas a qualquer tempo. O método de manutenção destes organismos requer que sejam conservados em baixa atividade biológica para preservar as características de esporulação e patogenicidade. O objetivo deste trabalho foi desenvolver metodologias para produzir, avaliar a sobrevivência e preservar as estruturas de resistência dos fungos Fusarium oxysporum f.sp. lycopersici raça 2, Macrophomina phaseolina, Rhizoctonia solani GA4 HGI, Sclerotium rolfsii, Sclerotinia sclerotiorum e Verticillium dahliae. O primeiro experimento foi feito no delineamento de parcelas inteiramente casualizadas em que a sobrevivência das estruturas de resistência dos seis fungos foi avaliada mensalmente por seis meses, em condições de campo e de laboratório. Para tanto, estruturas de cada fungo, produzidas através das metodologias desenvolvidas, foram enterradas no campo a 10 cm de profundidade e outras mantidas no laboratório. O objetivo deste experimento foi verificar a eficiência das metodologias para manter e também para avaliar a capacidade da sobrevivência dos patógenos, permitindo desta forma, manusear as estruturas de resistência de todos os fungos estudados. No segundo experimento, frascos de 500 mL (duas repetições/fungo) contendo estruturas de resistência, produzidas através das 2 metodologias desenvolvidas, foram mantidos em temperatura natural de laboratório, de refrigeração (º5C) e de freezer (-20ºC) para determinar a melhor condição para preservar as estruturas de cada fungo...(Resumo completo, clicar acesso eletrônico abaixo)
Soilborne phytopathogenic fungi cause great losses in economical cultures. These organisms produce resistance structures in the absence of hosts and / or unfavorable climatic conditions. These structures, when presents, make unfeasible the pathogen control. The preservation of fungi for long periods is important to make possible researches the any time. The method of maintenance of these organisms requests that are conserved in low biological activity to preserve the sporulate characteristics and pathogenicity. The objective of this work was to develop methodologies to produce and to evaluate the survival and also to preserve the resistance structures of Fusarium oxysporum f.sp. lycopersici race 2, Macrophomina phaseolina, Rhizoctonia solani AG4 HGI, Sclerotium rolfsii, Sclerotinia sclerotiorum and Verticillium dahliae. The first experiment was carried out in a randomized plots design where the survival of the resistance structures of the six fungi was monthly evaluated for six months under field and laboratory conditions. The structures of each fungus, produced through the developed methodologies, were buried in the field at 10 cm of depth and another maintained at the laboratory. The objective of this experiment was to verify the efficiency of the methodologies to maintain and also to evaluate the survival capacity of the pathogens in order to set methodologies to handle the resistance structures of those fungi. In the second experiment 500 mL flasks (two repetitions/fungus) containing resistance structure produced through developed methodologies were maintained at room, refrigerator and freezer temperature to determine the best condition to preserve the structures those pathogens. Monthly and for a period of 4 one year the survival and the vigour of each pathogen were evaluated on their specific medium...(Complete abstract click electronic access below)
Doutor
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33

Brenneman, Timothy Branner. "Sensitivity and resistance of Sclerotinia minor to fungicides for control of Sclerotinia blight of peanut." Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/49993.

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Sclerotinia blight, caused by Sclerotinia minor, is a severe disease of peanut in Virginia. Vinclozolin (V), iprodione (I), dicloran (D), and pentachloronitrobenzene (PCNB) were evaluated for their fungitoxicity to S. minor. The mean ED₅₈ values for five isolates were found to be 0.07, 0.11, 0.91, and 1.27 μg/ml, for V, I, D, and PCNB, respectively, on fungicide-amended glucose yeast-extract agar (GYEA). Fungicide-resistant growth sectors developed on media amended with I or V. Nine such strains occurred; they were capable of growth on GYEA amended with up to 1000 μg/ml of I or V, and were cross-resistant to D or PCNB. Resistance was maintained in all but two strains after repeated culture in the absence of fungicide for 3 yr. In field microplots, two resistant strains were pathogenic to peanut and survived as well as a fungicide-sensitive field isolate. D, I and V were applied to peanuts in the microplots for 3 yr at total annual rates of 8.41, 3.36, and 2.52 kg/ha, respectively. Disease severity caused by the resistant strains was suppressed 19, 33, and 87% by D, I, and V, respectively, as compared to 15, 24, and 76% for the sensitive isolate. Isolates recovered from tissue biopsies still grew on fungicide-amended GYEA indicating that in vitro and in vivo resistance are not equivalent in this case. Fungicide treatments reduced sclerotial populations of all strains, and reduced the viability of sclerotia from sensitive but not resistant strains. Fungicide-resistant strains were capable of surviving and competing pathogenically in microplots infested with equal numbers of sclerotia from a sensitive and a resistant strain; this trend was enhanced by fungicide applications. A survey of 763 isolates from fields treated with these fungicides failed to detect resistant strains. One fungicide-resistant isolate was recovered from an iprodione-treated microplot originally infested with a sensitive field isolate. A technique utilizing excised peanut stems was devised to evaluate isolate pathogenicity, cultivar resistance to the disease, susceptibility of different age peanut tissues, and fungicide persistence on peanut stems in the field. The method was also used to screen fungicides; results verified previous findings which indicated that in vitro resistance is not equivalent to in vivo resistance. Resistance to these fungicides may eventually become a field problem, but with correct management they should provide years of disease control.
Ph. D.
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34

Mudziwa, Nyengedzeni. "Yield and quality responses of Egyptian white garlic (Allium sativum L.) and wild garlic (Tulbaghia violacea Harv.) to nitrogen nutrition." Diss., University of Pretoria, 2010. http://hdl.handle.net/2263/28945.

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Allium sativum and Tulbaghia violacea are some of the most important medicinal plants used by South African traditional healers for the treatment of flu, fever, cold, tuberculosis, asthma and many more diseases. However, growth, yield and quality are constrained by excessive and under fertilization. This study was carried out to determine, firstly, the effect of N source (ammonium sulphate and calcium nitrate) on yield and quality of A. sativum and T. violacea plants. Secondly, to determine the best season for harvesting T. violacea and lastly, to determine the antifungal effects of A. sativum and T. violacea plant extracts against plant pathogens Altenaria solani and Sclerotium rolfsii. Both plants were treated with both N sources applied as topdressing treatments at a total of 0, 50, 100, 150 and 200 kg.ha-1, divided into three applications at three week (A. sativum) and three month (T. violacea) intervals. A. sativum plants were sampled at 54, 82, 112, 140 and 175 days after planting (DAP) while, T. violacea plants were sampled monthly for ten months. Parameters recorded were growth analysis, yield and bioactivity for both plant species. Both nitrogen sources improved plant growth and yield of A. sativum and T. violacea plants. Calcium nitrate at 150 kg•ha-1 and ammonium sulphate at 200 kg•ha-1 produced the highest at 24 t•ha-1 and 27 t•ha-1, respectively. Ammonium sulphate improved bioactivity of leaves with the highest bioactivity recorded at 82 and 112 DAP. Yield obtained from the autumn harvest was not affected by N source. Ammonium sulphate and calcium nitrate at 200 kg•ha-1 produced the highest yields of 23.6 t•ha-1 and 23.5 t•ha-1, respectively. In contrast, yield obtained from the winter harvest was affected by N source at 200 kg•ha-1, with significantly better yield of 30.8 t•ha-1 with calcium nitrate compared to 27.4 t•ha-1 with ammonium sulphate. Crude extracts of T. violacea bulbs that were treated with ammonium sulphate significantly inhibited the growth of plant pathogenic fungi, whereas extracts from plants treated with calcium nitrate showed low bioactivity. Extracts from plants grown with ammonium sulphate at 100 kg•ha-1 were more effective in controlling growth of plant pathogens when compared to other N levels. The minimum inhibitory concentration (MIC) effects of A. sativum against S. rolfsii and A. solani were at 0.01 mg•mL-1. The MIC of T. violacea extracts against A. solani was at 0.006 mg•mL-1. The MIC of T. violacea extracts were better than previously reported in literature. Therefore, A. sativum and T. violacea plant extracts can be used as fungicides against S. rolfsii and A. solani diseases for crops such as tomato and potato.
Dissertation (MInstAgrar)--University of Pretoria, 2010.
Plant Production and Soil Science
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35

SOUZA, Leonardo Tavares de. "Potencial de leveduras no controle biológico da podridão-de-esclerócio em feijão caupi." Universidade Federal Rural de Pernambuco, 2013. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6608.

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The southern blight, caused by Sclerotium rolfsii soilborne fungi, is an important disease in the culture of cowpea (Vigna unguiculata). The present work aimed: a) select, identify and verify the stability of antagonistic yeast isolates to S. rolfsii for biological control potential of rot southern blight in cowpea; b) elucidate the possible antagonistic activity in vitro of the yeast S. rolfsii, and the ability of yeast for growth promotion of cowpea plants. The experiments were conducted under conditions of a green house and in vitro assays. A total of five isolates, among 74 evaluated yeasts were selected in order to reduce the severity of southern blight in cowpea plants caused by an isolate of S. rolfsii pre selected in pathogenicity tests. Experimental tests showed that four out of five selected strains of yeast were stable in reducing disease severity in plants against three different isolates of S. rolfsii. There was a significant decrease in disease control was reduced when the concentration of these isolates yeast suspensions for seed treatment. The five selected yeast isolates were submitted to classification by classical taxonomy, considering the morphological, physiological and biochemical, as well as identifying the level of molecular biology, through sequencing of genomic regions ITS1 and ITS4. The five selected yeast isolates were identified as belonging to species Kodamaea ohmeri. In assays in vitro, all five strains of K. ohmeri showed activity "killer" positive, and observed an inhibition of mycelial growth of isolates of S. rolfsi grown on culture medium containing filtered extracted from strains of K. ohmeri for the majority of interactions tested. In tests of colonies pairings, only one isolate of K. ohmeri was effective in inhibiting the mycelial growth of two isolates of S. rolfsii between three pathogen strains evaluated. The tests of promoting plant growth, all five isolates K. ohmeri selected have generated significant gains in Shoot biomass of plants from seed treatment. The use of isolated K. ohmeri selected been shown as a promising tool for biological control to be incremented in the management of diseases caused by S. rolfsii in cowpea culture
A podridão-de-esclerócio, causada pelo fungo habitante do solo Sclerotium rolfsii, é uma importante doença na cultura do feijão caupi (Vigna unguiculata). O presente trabalho teve como objetivos: a) selecionar, identificar e verificar a estabilidade antagônica de isolados de leveduras a S. rolfsii no potencial de controle biológico da podridão-de-esclerócio em feijão caupi; b) elucidar as possíveis atividades antagônicas in vitro de leveduras sobre S. rolfsii, bem como a capacidade destas leveduras na promoção de crescimento de plantas de feijão caupi. Os experimentos foram conduzidos em condições de casa-de-vegetação e em ensaios in vitro. Um total de cinco isolados, dentre 74 leveduras avaliadas, foram selecionados visando a redução da severidade da podridão-de-esclerócio em plantas de feijão caupi ocasionada por um isolado de S. rolfsii pré-selecionado em testes de patogenicidade. Ensaios experimentais demonstraram que quatro dos cinco isolados de leveduras selecionados foram estáveis na redução da severidade da doença em plantas perante três diferentes isolados de S. rolfsii. Ocorreu uma significativa diminuição do controle da doença quando foi reduzida a concentração de suspensões destes isolados leveduras no tratamento de sementes. Os cinco isolados de leveduras selecionados foram submetidas à classificação por taxonomia clássica, considerando os caracteres morfológicos, fisiológicos e bioquímicos, bem como por identificação à nível de biologia molecular, através do sequenciamento das regiões genômicas ITS1 e ITS4. Os cinco isolados de leveduras selecionados foram identificados como pertencentes à espécie Kodamaea ohmeri. Em ensaios in vitro, todos os cinco isolados de K. ohmeri apresentaram atividade “killer” positiva, sendo observada uma inibição do crescimento micelial de isolados de S. rolfsi crescidos sobre meio de cultivo contendo filtrados extraídos dos isolados de K. ohmeri para a maioria das interações testadas. Em testes de pareamentos de colônias, somente um isolado de K. ohmeri foi eficiente na inibição do crescimento micelial de dois isolados de S. rolfsii entre três isolados do patógeno avaliado. Nos testes de promoção de crescimento de plantas, todos os cinco isolados de K. ohmeri selecionados geraram ganhos significativos na biomassa de parte aérea de plantas a partir do tratamento de sementes. O uso de isolados K. ohmeri selecionados, se demonstrou como uma ferramenta promissora de controle biológico a ser incrementada no manejo de doenças causadas por S. rolfsii na cultura caupi.
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36

Bontempo, Amanda Ferreira. "Seleção “in vitro” de isolados de Trichoderma spp. e Bacillus spp. em baixa temperatura de crescimento para o controle de Sclerotium cepivorum." Universidade Federal de Viçosa, 2016. http://www.locus.ufv.br/handle/123456789/7805.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
A podridão-branca, causada pelo fungo Sclerotium cepivorum, é uma das principais ameaças ao cultivo de plantas do gênero Allium. A aplicação de agentes de biocontrole pode contribuir para o manejo da doença, como espécies dos gêneros Trichoderma e Bacillus, que são inimigos naturais de S. cepivorum. A maioria dos isolados desses antagonistas cresce em temperaturas de 25 a 30 oC, entretanto, alho e cebola são cultivados durante estações frias no Brasil (outono-inverno) e a germinação do escleródio ocorre entre 13 e 18 oC. Assim, a seleção de agentes de biocontrole deve visar isolados que crescem e inibem S. cepivorum sob temperaturas abaixo de 18 oC. O presente trabalho objetivou selecionar isolados de Trichoderma spp. e Bacillus spp. capazes de crescer e inibir a germinação de escleródios de S. cepivorum a 16 oC e avaliar o efeito dos isolados mais promissores no controle da doença em cebolinha em cultivo em incubadora e cebola cultivada em casa de vegetação e em campo. Doze dos 44 isolados de Trichoderma foram selecionados devido à habilidade de crescerem a 11 oC. Dentre eles, os isolados GF420, GF424 e GF426 reduziram em mais de 80 % a germinação de escleródios e colonizaram mais de 70 % dos escleródios em ambos os experimentos „in vitro‟ a 16 oC. Todos os isolados de Bacillus spp. (GF33, GF63, GF203, GF266 e GF340) reduziram a germinação de escleródios em mais de 80 %. Os isolados GF 203 e GF266 de Bacillus e GF420, GF424 e GF426 de Trichoderma foram avaliados em experimentos em incubadora do tipo BOD, casa de vegetação e campo visando ao controle de S. cepivorum em cebolinha e cebola. Para os experimentos em incubadora, o solo foi artificialmente infestado com cinco escleródios por 100 cm 3 de solo. Um campo localizado em Rio Paranaíba – Minas Gerais, naturalmente infestado com sete escleródios por 100 cm 3 de solo, foi usado como área experimental e fonte de solo para os experimentos em casa de vegetação. Houve incidência de podridão-branca apenas em poucas plantas nos experimentos de laboratório aos 63 dias de cultivo, e a doença não ocorreu em casa de vegetação e campo ao final de 140 dias. Assim, não foi possível avaliar o real potencial dos isolados no controle do patógeno na presença de hospedeiro suscetível. Os isolados GF420, GF424 e GF426 de Trichoderma spp. e GF33, GF63, GF203, GF266 e GF340 de Bacillus spp. colonizam e reduzem a germinação de escleródios de S. cepivorum a 16 oC. Experimentos adicionais em casa de vegetação e campo são necessários para selecionar pelo menos um isolado para o manejo da podridão-branca.
White rot, caused by the fungus Sclerotium cepivorum, is a major threat of Allium spp. The application of biocontrol agents can enhance the management of the disease. Trichoderma and Bacillus are natural enemies of S. cepivorum. The majority of the isolates of these antagonists grows at temperature from 25 to 30 oC. However, garlic and onion are cultivated during the cold seasons in Brazil (autumn-winter) and sclerotia germination of S. cepivorum occurs between 13 to 18 oC. Thus, the screening of biocontrol agents should target isolates which grow and inhibit S. cepivorum under temperatures below 18 oC. Therefore, the present work aimed to screen isolates of Trichoderma spp. and Bacillus spp. able to grow and inhibit sclerotia germination of S. cepivorum at 16 oC, and to assess the effect of the most promising isolates on the control of the disease in Japanese bunching onion grown in incubator and onion cultivated in greenhouse and field. Twelve out of 44 isolates of Trichoderma were selected due to the ability of growth at 11 oC. Among them, the isolates GF420, GF424 and GF426 reduced by more than 80 % the germination of sclerotia and colonized by more than 70 % the sclerotia in both of the in vitro experiments at 16 oC. All isolates of Bacillus spp. (GF33, GF63, GF203, GF266 and GF340) reduced the germination of sclerotia by more than 80 %. The isolates GF 203 and GF266 of Bacillus and GF420, GF424 and GF426 of Trichoderma were assessed in experiments carried out in incubator, greenhouse and field aiming the control of S. cepivorum in Japanese bunching onion and onion. For the experiments in incubator, the soil was artificially infested with five sclerotia/100 cm 3 of soil. A field located in Rio Paranaíba – Minas Gerais, naturally infested with seven viable sclerotia/100 cm 3 of soil, was used as experimental area and source of soil for experiments in greenhouse. There was incidence of white rot only in few plants in the incubator experiment at 63 days and the disease did not occur in both the greenhouse and field experiments at 140 days. Thus, it was not possible to assess the real potential of the isolates for the control of the pathogen in the presence of susceptible host. The isolates GF420, GF424 and GF426 of Trichoderma spp. and GF33, GF63, GF203, GF266 and GF340 of Bacillus spp. colonise and reduce the germination of sclerotia of S. cepivorum at 16 oC. Further greenhouse and field experiments are required to select at least one isolate for the greenhouse and field experiments are required to select at least one isolate for the management of the white rot.
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37

ALESI, NICOLA. "Osteoclast-specific Tsc2 deletion in mice increases bone mass: a model for the study of sclerotic bone lesions in Tuberous Sclerosis." Doctoral thesis, Università Politecnica delle Marche, 2017. http://hdl.handle.net/11566/245595.

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La maggior parte dei pazienti affetti da Sclerosi Tuberosa mostra lesioni ossee di tipo sclerotico, la cui patogenesi e’ sconosciuta. Le lesioni sclerotiche potrebbero rappresentare un eccessivo e focale accumulo di osso. Lo scheletro e’ continuamente rimodellato dall’azione di osteoblasti, le cellule che producono tessuto osseo e osteoclasti (OC), che lo degradano. Evidenze dimostrano che la perdita di TSC1 o TSC2 negli osteoblasti ha effetto negativo nella maturazione dello scheletro, ma la funzione del complesso TSC1-TSC2 negli OC non e’ noto. Per identificare il ruolo di TSC2 negli OC abbiamo incrociato un topo CtskCRE, in cui Cre e’ espresso negli OC, con un topo Tsc2fl/fl per generare un topo CtskCre; Tsc2fl/fl ora in avanti chiamato Tsc2ΔOC. I topi Tsc2ΔOC maschi presentano un incremento di 3 volte della quantita’ di osso trabecolare a 9 mesi di eta’ (p< 0.01), cosi’ come dello spessore della corticale ossea (1.5 volte, p<0.05). Caratteristiche simili sono osservate a 3 mesi di eta’. Come pronosticato, gli OC derivati da topi Tsc2ΔOC hanno elevazione di mTORC1 ma presentano una normale maturazione ed una normale attivita’ secretoria in vitro. Per studiare la funzione degli OC in vivo, abbiamo misurato i livelli sierici di CTX1, un marker della loro attivita’, trovandolo normale sia nei topi maschi che nelle femmine a 3 mesi di eta’, normale nelle femmine a 9 mesi di eta’ ed aumentato nei maschi a 9 mesi di eta’. La concentrazione sierica di P1NP, un marker di attivita’ degli osteoblasti e’ stata trovata elevata in tutti i gruppi considerati. Gli OC aumentano l’attivita’ degli osteoblasti mediante la secrezione di clastochine, un meccanismo chiamato coupling. L’ RNA messaggero di CTHRC1 (una clastochina) e’ aumentato di 11 volte (p<0.001) nei femori di topi Tsc2ΔOC a 3 mesi cosi come a 9 mesi di eta’. Il nostro modello suggerisce che la perdita di TSC2 negli OC possa stimolare gli osteoblasti a produrre osso tramite la mTORC1 dipendente secrezione di CTHRC1.
The majority of TSC patients have sclerotic bone lesions, the pathogenesis of which is unknown. Sclerotic lesions may represent focal accumulation of excess bone. Normal bone is continuously remodeled by the actions of bone forming osteoblasts and bone resorbing osteoclasts (OC). A growing body of evidence suggests that loss of TSC1 or TSC2 in osteoblasts impacts normal skeletal growth, but the function of the TSC protein complex in OC is unknown. To examine the impact of the TSC2 protein in OC, we crossed the Cathepsin K-Cre (Ctsk-Cre) mice, where Cre is expressed in OC, with Tsc2fl/fl mice to generate CtskCre; Tsc2fl/fl mice, subsequently denoted as Tsc2ΔOC. Tsc2ΔOC male mice have strikingly elevated trabecular bone mass at 9 months of age (~3-fold increase, p<0.01) as well as increased cortical thickness (1.5-fold, p<0.05). Similar characteristics were observed at 3 months of age. As expected, OCs from Tsc2ΔOC mice had increased mTORC1 activity, consistent with the loss of TSC2, however they show normal maturation and secretory function in vitro. To assess OC function in vivo, we measured serum levels of the degradation products of C-terminal telopeptide of type I collagen (CTX-I), an established bone resorption marker. CTX-I was found normal in male and females at 3 months of age and in 9 months old female; slightly elevated in male at 9 month of age meaning OCs are not responsible for the phenotype. The serum concentration of procollagen type I N propeptide (P1NP), a marker of osteoblast activity, was elevated in Tsc2ΔOCmice in both sex at 3 and 9 months of age. OCs increase osteoblast activity through the secretion of Clastokines, a mechanism called coupling. CTHRC1 (a clastokine) mRNA was found increased (11 fold, p< 0.001) in the femurs of 3 months old Tsc2ΔOC mice, as well as at 9 months old. Our model suggests that loss of Tsc2 in OCs may stimulate osteoblastic bone formation through the mTORC1 dependent secretion of CTHRC1.
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38

BLAGOJEVIC, JELENA. "Identification of HLA functional motifs associated with severe systemic sclerosis and sclerotic-graft versus host disease: The shared epitopes of fibrosis." Doctoral thesis, Università di Siena, 2016. http://hdl.handle.net/11365/1005497.

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Background: The aim of our study was to identify the HLA class II functional motifs (shared epitopes) associated with severe skin fibrosis in SSc and scl-GVHD. Methods: Seventy consecutive SSc patients (15 with diffuse (dSSc) and 55 with limited (lSSc) cutaneous subset) fulfilling 2013 ACR/EULAR classification criteria and 43 sclGVHD patients with skin fibrosis involving >50 % of body surface area recruited from National Cancer Institute observational clinical trial on chronic GVHD (04-C-0281) were enrolled in the study. High resolution HLA class II typing, HLA data alignment and identification and qualitative and quantitative analysis of amino acids corresponding to β chain hypervariable regions of HLA-DP, HLA-DQ and HLA-DR molecules were performed for all patients. For the qualitative analysis amino acids were classified according the three classic categories (non-polar, polar-neutral, polar-charged) and two subcategories (hydrophobicity and hydrophilicity). For the quantitative analysis Results: Comparison of amino acidic sequences of sclGVHD patients and dSSc patients with severe skin fibrosis (fibrotic phenotype), with data of lSSc patients (non-fibrotic phenotype) showed the lower prevalence of selected amino acidic motifs in patients with fibrotic phenotype compared with those with non-fibrotic phenotype. Thus these motifs displayed protective effect against skin fibrosis. Simultaneous presence of shared amino acidic motifs at different HLA molecules conferred higher degree of protection against skin fibrosis, compared to single epitopes (Table 2). Qualitative amino acidic analysis showed the major prevalence of hydrophobic and non-polar side chains at positions 11 and 26 of HLA – DP (p = 0.026) and HLA - DQ (p = 0.047) β chains respectively. Quantitative analysis showed that patients with non-fibrotic phenotype who did not possess the longest common amino acidic sequence of HLA-DP and HLA-DQ molecules had fewer differences from the common motifs than patients with fibrotic phenotype (p=0.0007 and p= for HLA – DP and HLA – DQ respectively). Conclusion: This is the first study which describes common sequences (shared epitopes), codified by three of the most important genes associated with SSc that seem to display a protective effect against severe fibrotic involvement in SSc and sclGVHD. We identified common amino acidic motifs within the hypervariable regions of β chains of HLA – DP, HLA – DQ and HLA – DR molecules present in patients with minimal skin fibrosis but not in patients who developed severe skin fibrosis. Additionally, we proposed to quantify functional differences within the HLA motifs to compare apparently different sequences for their functional ability of binding specific peptide residues. Our findings indicate this approach can add value to simple genotyping of HLA. Further studies on large populations are necessary to confirm our preliminary findings.
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39

GUERRA, Yrlânia de Lira. "Prospecção de óleos essenciais para o controle da murcha de esclerócio em amendoim." Universidade Federal Rural de Pernambuco, 2013. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6665.

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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
Brazil is a major producer of world agricultural production is limited by pests and diseases. Among the diseases Sclerotium rolfsii Sacc. is a fungus that causes major losses in agriculture by presenting more than 500 hosts and is present in all tropical regions. The effect of essential oils in control of wilt sclerotia, culture as having reference to the peanut crop, with subsequent recommendation in agricultural management, with a segment phytopathological. Using four different isolates of S. rolfsii was conducted mycelial growth rate, followed by the pathogenicity test in the peanut plants (cultivar BR 1), the SR5 was isolated which had the highest growth rate and more aggressive. The seven essential oils were selected for bioassay of inhibition at concentrations previously established, with the reference dosage of 1000 ppm. Being selected again at low concentrations, from 500 ppm, Palmarosa oil which was showed the highest inhibition rate of formation of sclerotia, the lowest dose tested that was 300 ppm. In the test of suppression of diffusion of oxalic acid was performed with the more aggressive isolated (SR5) with palmarosa oil at 400 ppm, which reduced the rate of mycelial growth by 55%. The bioassay establishment of the pathogen in the substrate and pathogenicity in peanut genotypes in a greenhouse with two genotypes, BR 1 and Senegal. The assay was performed with substrate Baseplant being added 40 g de P2O5 + 15 g KCl + 200 g de humus/kg substrate fertilized. BR Genotype 1 was more susceptible than Senegal, isolated SR5 was more aggressive, leading to higher rates of disease when grown only in substrate. In the validation assay of the oil against S. rolfsii in the greenhouse, was held with seven treatments and at the end of the cycle there was a weight gain of 54% of the pods, 57% in the number of pods/plant and harvest index of 40%.
O Brasil é um dos maiores produtores agrícolas mundiais do amendoim e sua produção é limitada por pragas e doenças. Dentre as doenças, destaca-se a murcha de esclerócio que causa grandes perdas na agricultura por apresentar mais de 500 hospedeiros e estar presente em todas as regiões tropicais. Avaliou-se o efeito dos óleos essenciais no controle da murcha de esclerócio tendo como cultura de referência ao amendoim. Foram testados quatro isolados de Sclerotium rolfsii avaliando-se a sua taxa de crescimento micelial em BDA (batata, dextrose e ágar) e patogenicidade no amendoim (cv. BR 1). O isolado SR5 foi o que apresentou a maior taxa de crescimento e o mais agressivo. Os sete óleos essenciais foram selecionados pela realização do bioensaio de inibição, com concentrações previamente estabelecidas, tendo como dosagem referencial 1000 ppm. Sendo novamente selecionados a baixas concentrações, a partir de 500 ppm. O óleo de Palmarosa foi o que apresentou a maior taxa de inibição de formação de esclerócios, na menor dose testada (300 ppm). O teste de supressão da difusão do ácido oxálico, foi realizado com o isolado mais agressivo (SR5), com o óleo de Palmarosa a 400 ppm, o qual reduziu a taxa de crescimento micelial em 55%. Para o teste de estabelecimento do patógeno no substrato Baseplant e de patogenicidade nos genótipos de amendoim em casa de vegetação utilizou-se dois genótipos, BR 1 e Senegal. O ensaio realizado com substrato recebeu adição de 40 g de P2O5 + 15 g KCl + 200 g de húmus/Kg como adubação básica. O genótipo BR 1, foi mais suscetível que Senegal, o isolado SR5 mostrou-se mais agressivo, provocando maior índice de doença quando cultivado apenas em substrato. O ensaio de validação do óleo contra S. rolfsii em casa de vegetação, foi realizado com sete tratamentos e ao final do ciclo da cultura observou-se um ganho de 54% no peso das vagens, 57% no número de vagens/planta e 40% no índice de colheita.
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40

Weber, Alison Roger Hajo. "PROGRAMAÇÃO GENÉTICA, REDES NEURAIS ARTIFICIAIS E TÉCNICAS DE BALANCEAMENTO NA MODELAGEM DE DADOS AGRÍCOLAS: ESTUDO DA DOENÇA MOFO BRANCO." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2012. http://tede2.uepg.br/jspui/handle/prefix/151.

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Data regression problems are common in the literature, therein it is desired to infer the relationship between the dependent (output) and independent variable (input) from a dataset. Infer the relationship between variables is not a simple task, many times there is a high non-linearity and noise in the data inside them. Two machine learning techniques that are able to work with this type of information are investigated, the Genetic Programming and Artificial Neural Networks. Still, in many cases the machine learning technique cannot find a satisfactory solution due to the unbalance of the database. Therefore, the aim of this study was to apply machine learning techniques in regression of unbalanced data, evaluating and comparing the results obtained with different approaches. The balancing method used is summarized in constructing weights to the data set, one for each sample, which represents the importance of example during the learning process model. This problem of unbalanced data modeling applies in a real agronomic data modeling, specifically in the study of white mold disease caused by the fungus Sclerotinia sclerotiorum (Lib.) de Bary. Due to the high destructive power of the disease to crops, knowledge of the presence of resistance structures called sclerotia in an area is of paramount importance so that appropriate actions are taken to treat the disease. In this case study, the task is to use learning techniques to build a predictive model of sclerotia from meteorological characteristics and location of the sample to the state of Paraná, using a set of unbalanced data. Different approaches to the techniques and the balancing method was employed for constructing the model. The Artificial Neural Networks with resilient propagation learning algorithm achieved better performance in creating the model for prediction of sclerotia able to predict the actual outcome with a correlation of 0.763 and a mean absolute error of 24.35. To identify if the employee balancing method improved the results we applied the Kruskal-Wallis test. The test showed that there is a statistically significant improvement between genetic programming with and without balancing technique. However the technique that showed the best results was the neural network with resilient propagation learning algorithm, the data set of white mold and in some cases experimental.
Problemas de regressão de dados são comuns na literatura, neles deseja-se inferir a relação entre variáveis dependentes (saída) e variáveis independentes (entrada) a partir de um conjunto de dados. Inferir esta relação entre as variáveis não é uma tarefa simples, por muitas vezes existirem uma alta não linearidade nos dados e pelo ruído existente neles. Duas técnicas de aprendizagem de máquina que são capazes de trabalhar com este tipo de informação são investigadas, a Programação Genética e as Redes Neurais Artificiais. Ainda assim, em muitos casos a técnica de aprendizado de máquina não consegue encontrar uma solução satisfatória, devido ao desbalanceamento da base de dados. Portanto, o objetivo deste trabalho foi aplicar técnicas de aprendizagem de máquina na regressão de dados desbalanceados, avaliando e comparando os resultados obtidos com diferentes abordagens. O método de balanceamento empregado resume-se em construir pesos para o conjunto de dados, um para cada exemplo, que representa a importância do exemplo durante o processo de aprendizagem do modelo. Este problema de modelagem em dados desbalanceados aplica-se em um caso real de modelagem de dados agronômicos, mais especificamente no estudo da doença mofo branco, causada pelo fungo Sclerotinia sclerotiorum (Lib.) de Bary. Devido ao alto poder destrutivo da doença para as culturas, o conhecimento da presença das estruturas de resistência chamadas de escleródios em uma área é de suma importância para que se tomem atitudes adequadas para o tratamento da doença. Neste estudo de caso, a tarefa é utilizar as técnicas de aprendizagem para a construção de um modelo de previsão de escleródios a partir de características meteorológicas e do local da amostra para o estado do Paraná, utilizando um conjunto de dados desbalanceados. Diferentes abordagens com as técnicas e com o método de balanceamento foram empregadas na construção do modelo. As Redes Neurais Artificiais com o algoritmo de aprendizagem resilient propagation obtiveram um melhor desempenho na criação do modelo para previsão de escleródios, conseguindo prever o resultado real com uma correlação de 0,763 e um erro médio absoluto de 24,35. Para identificar se o método de balanceamento empregado melhorou os resultados obtidos foi aplicado o teste de Kruskal-Wallis. O teste mostrou que existe uma melhora estatisticamente significativa entre a programação genética com e sem a técnica de balanceamento. Porem a técnica que apresentou melhores resultados foi a Rede Neural com o algoritmo de aprendizagem resilient propagation, no conjunto de dados do mofo branco e em alguns casos experimentais.
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41

Viscardi, Bernardo Souza Mello. "Influência do esterco bovino no desenvolvimento do feijão caupi (Vigna unguiculata) e no controle de Sclerotium rolfsii em feijoeiro comum (Phaseolus vulgaris) na presença ou não de Trichoderma harzianum." reponame:Repositório Institucional da UnB, 2013. http://repositorio.unb.br/handle/10482/13877.

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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Agronomia e Medicina Veterinária, Programa de Pós-Graduação em Agronomia, 2013.
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O feijoeiro comum (Phaseolus vulgaris) e o caupi (Vigna unguiculata) são culturas de grande importância para o Brasil. Doenças, cujos patógenos sobrevivem e se multiplicam no solo, como a podridão radicular causada por Sclerotium rolfsii, é um dos principais fatores que limitam a produtividade dessas culturas. O alto custo do uso de fungicidas e os problemas ambientais associados ao uso de agroquímicos levaram a um incremento na pesquisa de métodos alternativos para o controle de doenças. Na primeira parte deste trabalho foi testada a eficiência do esterco bovino (0, 10, 20, 40, 80 e 160 g/kg de solo) e a combinação destas com a inoculação de sementes de feijão-caupi com Trichoderma harzianum e procimidona, na produção de massa de grãos, massa de parte aérea, massa de raízes e altura de plantas. A segunda parte avaliou a eficiência da aplicação de T, harzianum e procimidona ao solo no controle de S. rolfsii e o impacto dessas técnicas combinadas com esterco bovino (0, 40, 80 e 160g/kg de solo), nas características biométricas do feijoeiro comum. Nos dois experimentos as doses crescentes de esterco foram favoráveis ao desenvolvimento da massa de parte aérea, de raízes e de grãos. Trichoderma harzianum mostrou ter influência positiva na produtividade de grãos de caupi e na redução da podridão em P. vulgaris contaminadas com S. rolfsii (UB 193). ______________________________________________________________________________________________________ ABSTRACT
The common bean (Phaselous vulgaris) and the cowpea (Vigna unguiculata) are important crops in Brazil. Soil-borne diseases, such as the southern blight (Sclerotium rolfsii), is among the causes of yield reduction. The high costs of fungicide applications and the environmental problems, the chemicals might cause, led to an increase in research of alternative methods for disease control. Therefore, in the first part of this work, cattle manure (0, 10, 20, 40, 80 and 160 g/kg of soil) was added to soil. Vigna seeds were treated with Trichoderma harzianum or procimidone and sowed in soil with or without cattle manure. The following variables were evaluated for each combination of treatment: seed germination, total grain weight, fresh plant weight, fresh root weight, and plant height of cowpea. The second part of the study was conducted to measure the effects of T. harzianum and procimidone applied on soil amended with cattle manure (0, 40, 80, and 160 g/kg of soil) on southern-blight of common bean. The same biometric variables were evaluated as in the first part of the study. The increasing manure doses resulted in greater fresh weight of grains, plants, and roots. The application of T. harzianum into soil had a positive impact on the cowpea yield and in the decrease of disease (S. rolfsii UB 193) on P. vulgaris.
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42

Castanho, Gisela Muassab. "Estudo comparativo in vitro das estruturas orgânicas e inorgânicas da dentina saudável e esclerosada humana e bovina: nanodureza, concentração de Ca e P e análise morfológica." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/23/23134/tde-22122010-112739/.

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A dentina esclerosada é um substrato comumente encontrado em pacientes idosos. No entanto, existem poucos estudos comparativos entre dentina humana e bovina esclerosadas. O objetivo deste estudo foi comparar os componentes inorgânicos e orgânicos da dentina saudável e esclerosada humana e bovina, através de cinco parâmetros: nanodureza, módulo de elasticidade, análise quantitativa da concentração de Cálcio (Ca) e Fósforo (P), densidade tubular e morfologia do colágeno. Trinta dentes humanos e 30 bovinos foram distribuídos em 4 grupos experimentais (n=15 por grupo): dentina humana saudável (DHS), esclerosada humana (DEH), bovina saudável (DBS), e bovina esclerosada (DBE). Os dentes saudáveis foram preparados na mesma altura e inclinação dos dentes esclerosados expondo níveis similares da dentina e obtendo fragmentos com 2mm de espessura. Foram realizadas 3 medições por espécime em 3 áreas pré determinadas de dentina intertubular com a utilização do Nanoindentador (carga de 500N por 5 s). Cinco espécimes de cada grupo foram preparados para Microscopia Eletrônica de Varredura (MEV). Com o auxílio da Energia Dispersiva por Raios-X EDX foram obtidos os valores (em percentagem) das concentrações de Ca e P e calculada a relação Ca:P. A contagem dos túbulos por área foi realizada em todas as eletromicrografias. Após descalcificação e preparo, o restante dos espécimes foi analisado em Microscopia Eletrônica de Transmissão (MET). DBS obteve maiores valores de nanodureza comparada à DBE e DHS. DHE sem diferenças com DHS e DBE (p=0,0008). DBS exibiu maiores valores de módulo de elasticidade somente comparada à DHS (p=0,000). A análise estatística não demonstrou diferenças estatisticamente significantes (p=0,71) entre as concentrações de Ca e P. Quanto à densidade tubular (número de túbulos/mm²), os grupos saudáveis foram maiores que os esclerosados e os humanos maiores que os bovinos. As fibras colágenas da DBS mostraram-se mais compactadas e mais desorganizadas que as demais. Pôde se concluir que apenas as concentrações de Ca e P foram similares e que as dentinas esclerosadas humana e bovina mostraram similaridade. Esta pesquisa teve suporte da Fapesp sob o número 2008/10290-8.
The sclerotic dentin has been commonly found in elderly patients. However, there are scarce reports in the literature comparing on the use of human and bovine sclerotic dentins. The objective of this study was to compare inorganic and organic components of healthy and sclerotic dentins from human and bovine. Five parameters were analyzed: nanohardness, elastic modulus, quantitative analysis of Calcium (Ca) and Phosphorous (P) concentrations, tubular density and ultrastructural morphology. Thirty human teeth plus 30 bovine teeth were distributed in 4 experimental groups (n=15 per group): human healthy dentin (HHD), human sclerotic dentin (HSD), bovine healthy dentin (BHD) and bovine sclerotic dentin (BSD). Healthy teeth were cut in the same level and inclination of the sclerotic superficial dentins. The nanohardness and elastic modulus (GPa) of three pre determined areas of each exposed dentin was measured using a nanoindenter (500N for 5s). Five samples of each group were prepared for scanning electron microscopy (SEM) examination. Energy Dispersive X-ray (EDX) was used for obtaining the Ca/P ratio. The tubular density was obtained by counting the tubules in scanning electron micrographs taken in the same magnification and work distance. Data were statistically analyzed by ANOVA complemented by the Tukeys test (p0.05). The ultrastructure of the dentins was observed in specimens processed for transmission electron microscopy (TEM). BHD exhibited significant higher nanohardness than BSD and HHD. HSD nanohardness was similar to those of HHD and BSD (p=0,0008). BHD exhibited significant higher elastic modulus than HHD (p=0,000). The Ca:P ratios were similar amongst all groups (p=0.71). The tubular densities were higher in the healthy dentins than in the sclerotic for both human and bovine. The human dentins presented higher tubular densities than bovine dentins (p=0.000). The intertubular dentin of BHD showed short collagen fibers distributed in a condensed fashion; whereas the other dentins exhibited well-organized long bundles of collagen fibers. It was concluded that sclerotic dentins of human and bovine share most morphological and structural characteristics. This research was supported by Fapesp grants number 2008/10290-8.
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43

Teles, Héria de Freitas. "Qualidade de sementes de soja e incidência de Sclerotinia sclerotiorum (lib) de Bary em função do beneficiamento e armazenamento." Universidade Federal de Goiás, 2012. http://repositorio.bc.ufg.br/tede/handle/tede/8826.

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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
Soybean (Glycine max L. Merrill) is considered the worldwide leader in oilseed production and consumption, and currently the main source of vegetable protein available. In the field, the crop is infected by a large number of diseases. Among the fungal diseases, the white mold, caused by Sclerotinia sclerotiorum (Lib) de Bary, has emerged as one of the most serious, affecting the quality of seed, which can also be influenced by processing and storage. The pathogen survives in soil through resistance structures (sclerotia) and can attack more than 400 host species. The objective of this study was to evaluate the physical and physiological quality and S. sclerotiorum incidence of soybean seeds during processing and six months after in cold and dry storage and environment conditions. Seeds from eight cultivars, coming from production fields, naturally infested with S. sclerotiorum, located in Vianópolis, Silvânia, Luziânia and Orizona in the State of Goiás, in the seasons 2009/2010 and 2010/2011 were studied. Samples were collected at each stage of processing: in the hopper (reception), after pre-cleaning, discard one (precleaning), after cleaning, after the sieve classifiers (three sieve sizes), after the spiral (three sieve sizes), after gravity table (three sizes of sieve) and final disposal, totalizing 14 samples. The following analysis were done: moisture content, physical purity, germination and tetrazolium test, and tests for S. sclerotiorum detection in rolled paper and Neon method. PCA analysis was performed and Pearson correlations study between the averages of the variables in processing stages for each cultivar. Processing improves physical and physiological quality of soybean seeds, which is efficient for S. sclerotiorum control, eliminating the sclerotia associated to the seeds and reducing the amount of inoculum that could return to the planting area. Physical purity, germination, viability and vigor are positively correlated together and negatively with the mass of sclerotia. Processing also reduces significantly the inoculum potential in the mycelial form of S. sclerotiorum in the seeds. Storage does not influence the incidence of S. sclerotiorum in mycelial form in seeds, which can increase or not during this period, regardless the storage conditions, in a cold and dry storage or in environment condition.
A soja (Glycine max L. Merrill) é considerada a oleaginosa líder em produção e consumo em todo o mundo, sendo, atualmente, a principal fonte de proteína vegetal disponível. Em campo, a cultura é infectada por grande número de doenças. Entre as doenças fúngicas, o mofo-branco, causado por Sclerotinia sclerotiorum (Lib) de Bary, tem se destacado como uma das mais graves, afetando a qualidade das sementes, a qual também pode ser influenciada pelo beneficiamento e armazenamento. O patógeno sobrevive no solo por meio de estruturas de resistência (escleródios) e pode atacar mais de 400 espécies hospedeiras. O objetivo deste trabalho foi avaliar a qualidade física e fisiológica e a incidência de S. sclerotiorum em sementes de soja durante o processo de beneficiamento e após seis meses de armazenamento em câmara fria e seca e em condição ambiente. Trabalhou-se com sementes de oito cultivares, provenientes de campos de produção naturalmente infestados por S. sclerotiorum, situados em Vianópolis, Silvânia, Luziânia e Orizona, no Estado de Goiás, safras 2009/2010 e 2010/2011. As amostras foram coletadas em cada etapa do beneficiamento: na moega (recepção), após a pré-limpeza, no descarte um (da pré-limpeza), após a limpeza, após os classificadores de peneira (três tamanhos de peneira), após o espiral (três tamanhos de peneira), após a mesa de gravidade (três tamanhos de peneira) e no descarte final da UBS, totalizando 14 amostras. Foram realizadas análises de teor de umidade, pureza física, testes de germinação e de tetrazólio, e os testes para a detecção de S. sclerotiorum em rolo de papel e método neon. Foi realizada análise de PCA e estudo das correlações de Pearson entre as médias das variáveis das etapas de beneficiamento, para cada cultivar. Verificou-se que o beneficiamento aprimora as qualidades físicas e fisiológicas das sementes de soja, sendo uma ferramenta útil para o controle de S. sclerotiorum, já que elimina os escleródios associados às sementes, e reduz a quantidade de inóculo inicial no campo. Pureza física, germinação, viabilidade e vigor estão correlacionadas positivamente entre si, e negativamente com a massa de escleródios. O beneficiamento também reduz significativamente o potencial de inóculo na forma micelial de S. sclerotiorum nas sementes. O armazenamento não influencia a incidência de S. sclerotiorum na forma micelial nas sementes, a qual pode aumentar ou não durante este período, independente das condições de armazenamento, seja em câmara fria e seca ou em condição ambiente.
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44

Wutzki, Carlos Rafael. "ANÁLISE ESPACIAL E QUANTIFICAÇÃO DE INÓCULO DE MOFO BRANCO (Sclerotinia sclerotiorum (Lib) de Bary) NA CULTURA DA SOJA (Glycine max (L) Merril)." Universidade Estadual de Ponta Grossa, 2017. http://tede2.uepg.br/jspui/handle/prefix/2446.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
O conhecimento da dinâmica espacial de doenças de plantas, aliado a quantificação de inóculo e monitoramento das condições meteorológicas é de grande importância para a adoção de estratégias de manejos adequados e com menor impacto ambiental. Sendo assim, os objetivos deste trabalho de pesquisa foram caracterizar a distribuição, variabilidade espacial e possíveis relações entre atributos referentes ao mofo branco e atributos de plantas de soja além de avaliar técnicas de identificação e quantificação de ascósporos de Sclerotinia sclerotiorum durante o florescimento da soja. Foram realizadas amostragens através de uma malha georreferenciada em uma área de 12 hectares (ha) no município de Mauá-da-Serra-PR nas safras 2013/14 e 2014/15 e uma área de quatro hectares no município de Ponta Grossa-PR na safra 2015/16. Foram utilizados quadrats com área útil de 7,2 m² para avaliação das seguintes variáveis: escleródios presentes no solo, estande da cultura, incidência, índice de doença, rendimento, escleródios produzidos na colheita, além da deposição do bioaerossol, partes de folha e flores da soja como uso de Meio Semi-seletivo a Sclerotinia sclerotiorum (MSS) e Reação em cadeia da polimerase quantitativa (qPCR), em 36 pontos de amostragem na área de Ponta Grossa-PR, em três datas durante o florescimento da soja. Os dados foram analisados com uso de estatística descritiva, ajuste de semivariogramas e matriz de correlação de Pearson. As condições meteorológicas observadas nos três experimentos foram adequadas para o desenvolvimento da cultura da soja e do mofo branco na soja. As variáveis referentes a cultura da soja apresentaram coeficientes de variação baixos ou moderados e as variáveis referentes ao mofo branco apresentaram coeficiente de variação muito elevados. Os ajustes dos semivariogramas apresentaram diferenças nos três experimentos, com efeito pepita puro, ajuste linear, esférico e exponencial. A variável escleródios do solo apresentou efeito pepita puro nos dois experimentos em Mauá-da-Serra. Foram encontradas correlações significativas positivas entre a incidência do mofo branco e a produção de escleródios na colheita, além de correlação negativa com o rendimento nos três experimentos. A identificação de inóculo de mofo branco com incubação em MSS mostrou-se a técnica com maior sensibilidade, mas demanda de até 15 dias para a confirmação de S. sclerotiorum, tanto para bioaerossol, como flores e partes de folhas de soja. Foi possível otimizar o protocolo de extração de DNA e ciclo de reação para qPCR, além de gerar uma curva padrão com DNA oriundo de ascósporos de S. sclerotiorum, com ajuste ao modelo linear (R²=0,99) e eficiência de 92,2%. O uso de qPCR mostrou-se promissor para partes de folhas, sendo possível resultados em um dia de trabalho.
The knowledge of the spatial dynamics of plant diseases, allied with the quantification of inoculum and monitoring of the meteorological conditions, is important for the adoption of adequate management strategies and with less environmental impact. The aim of this work was to characterize the distribution, spatial variability and possible relations between white mold attributes and soybean plants attributes, as well as to evaluate techniques for identification and quantification of ascospores of Sclerotinia sclerotiorum during soybean flowering. Samplings were carried out through a georeferenced grid on a field of 12 hectares (ha) in the municipality of Mauá-da-Serra-PR in the 2013/14 and 2014/15 crop seasons and, on a field of four hectares in the municipality of Ponta Grossa-PR in the 2015/16 crop season. Quadrats with a useful area of 7.2 m² were used to evaluate the following variables: sclerotia in the soil, crop stand, incidence, severity, yield, sclerotia produced at harvest, as well as bioaerosol deposition, soybean leaf parts and flowers on semi-selective medium to Sclerotinia sclerotiorum (MSS) and quantitative polymerase chain reaction (qPCR), at 36 sampling points in the Ponta Grossa- PR field, at three dates during soybean flowering. Data were analyzed using descriptive statistics, semivariogram adjustment and Pearson correlation matrix. The meteorological conditions observed in the three experiments were adequate for the development of soybean crop and white mold disease. The variables related to soybean plants, showed low or moderate coefficients of variation and the variables related to white mold showed a high coefficient of variation. The semivariograms adjustments showed differences in the three experiments, with pure nugget effect, linear, spherical and exponential adjustments. The variable sclerotia of soil showed pure nugget effect on the two experiments in Mauá-da-Serra. Significant positive correlations were found between the incidence of white mold and the production of sclerotia at harvest, in addition to negative correlation to yield in the three experiments. The identification of white mold inoculum with incubation on MSS was shown to be the most sensitive technique, but takes up to 15 days for the confirmation of S. sclerotiorum pathogen for bioaerossol, flowers and parts of soybean leaves. It was possible to optimize the protocol of DNA extraction and reaction cycle for qPCR, besides generating a standard curve with DNA from ascospores of S. sclerotiorum, adjusted to the linear model (R² =0, 99) and efficiency of 92.2%. The use of qPCR showed promise results for leaf parts, being possible achieve concluding results in one working day.
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Van, Loenen Mariska C. A. "Treatment of soil-borne fungal pathogens Sclerotinia sclerotorium, Sclerotium cepivorum, Verticillium dahliae and Pythium ultimum, potato cyst nematodes Globodera rostochiensis and Globodera pallida, and weeds Chenopodium album and Agropyron repens with low-temperature/short-duration steam and with ozone gas." Thesis, University of Aberdeen, 2003. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU602318.

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Methyl bromide is a widely used soil disinfectant that, because of its ozone depleting properties, is being phased out in the EC by 2005.  Soil steaming is a well-established system of soil disinfestation and is increasingly seen as a viable option to methyl bromide replacement.  Traditional glasshouse steaming techniques create a number of problems because it involves treatment of soil with high-temperature (100-140°C) steam for up to eight hours or more.  This not only eliminates unwanted soil-borne pests and diseases, but also creates a ‘biological vacuum’, in which target pests and pathogens may quickly re-enter and luxuriate, perpetuating the need for regular disinfestation.   Soil steaming at lower temperatures, e.g. at 70°C, does not normally result in these unwanted side effects, because of the partial survival of the saprophytic microflora population. In this study agricultural soil samples, containing a range of important soil-borne pests and pathogens, were treated with steam in a specially designed laboratory steam-rig.  It was found that treatment at 60°C, for a duration of only 3 minutes plus eight minutes ‘resting’ (“low-temperature/short duration soil steaming”) was enough to 100% kill soil-borne fungal pathogens Sclerotinia sclerotiorum, Sclerotium cepivorum, Verticillium dahliae and Pythium ultimum;  potato cyst nematodes Globodera rostochiensis and Globodera pallida, and weeds Chenopodium album and Agropyron repens. When low temperature/short duration soil steaming was compared with a chemical soil disinfectant, using the fumigant dazomet (Basamid) at a rate of 760 kg/ha, both disinfestation methods resulted in 100% elimination of the above pathogens, nematodes and weeds and caused IGR (Increased Growth Response) of lettuce plants. In a further study, using four different soil types at three different matric potentials, it was found that efficacy of low-temperature/short duration steaming is dependent on soil type and soil moisture content, and that treatment of soil in a moist state is more effective than treatment in a dry state, especially when treating fine-textured sand and loam soils. Soil samples containing survival structures of soil pests were also treated with ozone gas in a specially designed ozone treatment chamber, but this did not result in elimination of target organisms.
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46

Chen, Dian-Yi, and 陳殿義. "Survival and control of the pathogen of chrysanthemum sclerotial disease." Thesis, 1988. http://ndltd.ncl.edu.tw/handle/81641561986062367559.

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47

Liang, Yue. "A proteome-level analysis of the canola/Sclerotinia sclerotiorum interaction and sclerotial development." Phd thesis, 2010. http://hdl.handle.net/10048/1228.

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The fungal pathogen Sclerotinia sclerotiorum (Lib.) de Bary is capable of infecting over 400 plant species including canola (Brassica napus L.). The fungus secretes oxalic acid (OA), which plays an important role in infection and disease progression. An analysis of proteome-level changes associated with infection of susceptible canola leaves by S. sclerotiorum revealed significant changes in the abundance of 32 proteins, including proteins involved in photosynthesis and metabolism, hormone signaling, and antioxidant defense. A similar subset of 37 proteins was affected when leaves were treated with OA alone; this compound also caused a reduction in the activities of a number of antioxidant enzymes, suggesting an OA-mediated suppression of the oxidative burst. To further understand the mechanisms of pathogenesis, the role of Sssp, a predicted secreted protein from S. sclerotiorum, was targeted for analysis. Mutant strains of S. sclerotiorum were generated by disruption of the Sssp gene and characterized for virulence on canola. Based on the extent of symptom development, the virulence of the Sssp-disrupted mutants was significantly reduced relative to the wild-type, indicating that Sssp may play a role in the infection process. Finally, the development of sclerotia, long-term survival structures that serve as a primary source of inoculum for the fungus, was examined. A total of 88 proteins were found to exhibit temporal changes in abundance during sclerotium formation and maturation, including proteins involved in the regulation of melanogenesis. A total of 56 proteins were also identified in the sclerotial exudates, providing a basis for future studies. Collectively, the studies described in this dissertation represent the most comprehensive proteome-level analysis of the canola/S. sclerotiorum interaction and sclerotial development, and could contribute to the development of novel strategies for the management of S. sclerotiorum.
Plant Science
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48

"In vivo and in vitro study of immunomodulatory activities of mushroom sclerotial polysaccharides." Thesis, 2008. http://library.cuhk.edu.hk/record=b6074643.

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Athymic nude mice were employed as the in vivo model to study the detailed mechanism of how the three sclerotial polysaccharides act to inhibit the growth of human xenografted tumors in vivo. Using immunohistochemical staining, it was found that the presence of F4/80 + macrophages was related to the reduction of tumor size of the HL-60 xenograft. mRNA extracted from the spleens were reverse-transcribed to cDNA and detected by real-time PCR so that a variety of genes related to the toll-like receptors being up-regulated or down-regulated due to the injection of mushroom sclerotial polysaccharides were determined. Combining the results from dectin-1 regulation, it was concluded that both hot water-soluble sclerotial polysaccharides, PTRW and PRW, having a structure of polysaccharide-protein complexes were responsible for activating and thus binding to CR3 or toll-like receptors while PRSon with structure of pure beta-glucan was responsible for activating the expression of dectin-1 receptor, which led to the subsequent activation of host immune system in immunopotentiation and antitumor activities.
In the future, further investigation of the detailed structure of mushroom sclerotial polysaccharides is required to explain the immunomodulatory mechanism so that the effective dosage for immunomodulation as well as antitumor effects can be determined. Furthermore, phage display can be applied to find out any novel glucan receptors specific to the mushroom sclerotial polysaccharides.
In vitro antitumor study indicated that PTRW had a significant (p<0.05) inhibitory effect (>40%) on the human monocytic leukemic cells (THP-1) in addition to HL-60 and K562 cells. In vitro immunomodulatory study showed that both PRW and PRSon had significant proliferative effects (p<0.05) on human normal spleen monocyte/macrophage cell, MD. Moreover, PRSon was shown to have a significant increase (p<0.05) in the growth of human natural killer cells, NK-92M1; however, PTRW showed a significant inhibition (p<0.05) on this cell line.
Mushroom sclerotia have a rich source of polysaccharides when compared with fruit bodies. It was previously reported that the polysaccharides from novel mushroom sclerotia, namely, Pleurotus tuber-regium and Polyporus rhinocerus, had potent in vitro and in vivo antitumor effects. In this project, hot water-soluble sclerotial polysaccharides of Pleurotus tuber-regium (PTRW), hot water-soluble and sonication-assisted cold alkali-soluble sclerotial polysaccharides of Polyporus rhinocerus (PRW and PRSon, respectively) were chosen for investigation of their in vivo and in vitro immunomodulatory effects.
Polysaccharides have long been proposed to exert their antitumor and thus immunomodulating functions through glucan receptors and among the four being discovered, Dectin-1 has drawn most attention recently. In the in vivo study, PRSon showed an increase in the expression of Dectin-1 on mice spleen MNCs while PTRW showed an increase in the expression of the previously widely-reported complement receptor (CR3). There was also an increase of Dectin-1 expression on PEC in the mice injected with PRSon. In the in vitro study, the three mushroom sclerotial polysaccharides were incubated with NK-92M1, MD and THP-1 cells. There was a significant increase (p<0.05) of Dectin-1 expression on NK-92MI cells incubated with PTRW. On the other hand, PTRW caused a significant decrease ( p<0.05) of Dectin-1 expression while PRSon showed a significant increase (p<0.05) on THP-1 cells. The cytokine profile of extra-cellular media indicated that the inhibition of THP-1 cells by PTRW should be related to the innate immunity. In the in vitro study, human primary immune cells, CD56+ NK cells were used to incubate with sclerotial polysaccharides and there was a significant stimulation (p<0.05) of their growth when compared with the control.
The in vivo immunomodulatory study was carried out by injecting the abovementioned sclerotial polysaccharides intraperitoneal to 7-8 weeks old healthy male BALB/c mice. The spleens excised from groups injected with PTRW and PRW were found to have significant increase of weight ( p<0.001). Flow cytometric analysis revealed that the NK cell population in spleen mononuclear cells (MNCs) of mice injected with PRW and PRSon was increased when compared with the control. In addition, ail three sclerotial polysaccharides showed a large increase of T helper cell population as well as CD4+/CD8+ ratio in spleen MNCs. On the other hand, the macrophage population in peritoneal exudates cells (PEC) was found to be increased in the groups of mice injected with PTRW and PRW.
Lai, Kin Ming Connie.
Adviser: Cheung Chi Keung.
Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3412.
Thesis (Ph.D.)--Chinese University of Hong Kong, 2008.
Includes bibliographical references (leaves 120-137).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstracts in English and Chinese.
School code: 1307.
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49

"Immunomodulatory activities of mushroom sclerotial polysaccharides isolated from Polyporus rhinocerus mediated by antigen-presenting cells." 2010. http://library.cuhk.edu.hk/record=b5894401.

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Choi, Man Wing.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2010.
Includes bibliographical references (leaves 126-139).
Abstracts in English and Chinese.
Chapter Chapter 1 --- Introduction --- p.1
Chapter 1.1 --- Antigen presenting cells (APC) in Immune systems --- p.1
Chapter 1.1.1 --- Dendritic cells --- p.2
Chapter 1.1.1.1 --- Differentiation of dendritic cells in mice --- p.2
Chapter 1.1.1.2 --- Maturation of dendritic cells --- p.3
Chapter 1.1.1.3 --- Stimulation and polarization of T cells stimulated by dendritic cells --- p.6
Chapter 1.1.2 --- Monocyte and macrophage --- p.7
Chapter 1.1.2.1 --- Differentiation of monocyte and macrophage in humans --- p.7
Chapter 1.1.2.2 --- Changes involved in differentiation of monocytes into macrophages --- p.9
Chapter 1.2 --- "Isolation, structure and activity of mushroom polysaccharides" --- p.13
Chapter 1.2.1 --- Sources of mushroom polysaccharides --- p.13
Chapter 1.2.2 --- Extraction methods --- p.14
Chapter 1.2.3 --- Structure-Activity Relationship (SAR) of mushroom polysaccharides --- p.15
Chapter 1.2.4 --- Previous studies on immunomodulatory effects of mushroom sclerotial polysaccharides --- p.18
Chapter 1.3 --- Recognition of β-glucan by specific receptors --- p.20
Chapter 1.3.1 --- Complement Receptor 3 (CR3) --- p.22
Chapter 1.3.1.1 --- Introduction of CR3 --- p.22
Chapter 1.3.1.2 --- Expressions of CR3 to recognize fungi --- p.22
Chapter 1.3.2 --- Dectin-1 --- p.24
Chapter 1.3.2.1 --- Introduction of Dectin-1 --- p.24
Chapter 1.3.2.2 --- Structure of Full-length Dectin-1 --- p.26
Chapter 1.3.2.2.1 --- Isoforms of Dectin-1 in Mice --- p.28
Chapter 1.3.2.2.2 --- Isoforms of Dectin-1 in Humans --- p.28
Chapter 1.3.2.3 --- Immune responses triggered by of Dectin-1 --- p.29
Chapter 1.3.3 --- Toll-like 2 receptor (TLR2) --- p.31
Chapter 1.3.3.1 --- Introduction of TLR2 --- p.31
Chapter 1.3.3.2 --- Structure of TLR2 --- p.33
Chapter 1.3.3.3 --- Immune responses triggered by TLR2 --- p.34
Chapter 1.4 --- Research Objectives --- p.35
Chapter Chapter 2 --- Materials and Methods --- p.38
Chapter 2.1 --- Materials --- p.38
Chapter 2.1.1 --- Mushroom sclerotia --- p.38
Chapter 2.1.1.1 --- Polysaccharide extraction from mushroom sclerotia --- p.38
Chapter 2.1.2 --- Antibodies and reagents --- p.41
Chapter 2.1.3 --- Human acute leukocyte monocytic cell line and culture medium --- p.42
Chapter 2.1.4 --- Preparation of murine bone marrow-derived immature dendritic primary cells (immature BMDCs) --- p.43
Chapter 2.2 --- Methods --- p.45
Chapter 2.2.1 --- Chemical Analysis --- p.45
Chapter 2.2.1.1 --- Measurement of monosaccharide profile --- p.45
Chapter 2.2.1.1.1 --- Acid depolymerisation --- p.45
Chapter 2.2.1.1.2 --- Neutral sugar derivatization --- p.45
Chapter 2.2.1.1.3 --- Gas chromatography (GC) --- p.46
Chapter 2.2.1.2 --- Determination of total sugar by phenol-sulfuric acid method --- p.47
Chapter 2.2.1.3 --- Determination of protein content by Lowry-Folin Method --- p.48
Chapter 2.2.1.4 --- Size exclusion chromatography by high pressure liquid chromatography (HPLC) --- p.49
Chapter 2.2.1.5 --- Endotoxin detection --- p.50
Chapter 2.2.2 --- Measurement of Bioactivities --- p.51
Chapter 2.2.2.1 --- Trypan blue exclusion assay --- p.51
Chapter 2.2.2.2 --- MTT cell proliferation assay --- p.51
Chapter 2.2.2.3 --- BrdU cell proliferation assay --- p.53
Chapter 2.2.2.4 --- Expression of cell surface markers --- p.54
Chapter 2.2.2.5 --- Phagocytosis / Endocytosis of FITC-labeled dextrans --- p.55
Chapter 2.2.2.6 --- Nitric oxide production assay --- p.55
Chapter 2.2.2.7 --- Reactive oxygen species production --- p.57
Chapter 2.2.2.8 --- Determination of cytokine profile using cytokine antibody array --- p.58
Chapter 2.2.2.9 --- Cell cycle analysis --- p.59
Chapter 2.2.2.10 --- Expression of surface receptors --- p.60
Chapter 2.2.2.11 --- Statistical analysis --- p.61
Chapter Chapter 3 --- Results and Discussion --- p.61
Chapter 3.1 --- Chemical characteristics of sclerotial polysaccharides --- p.61
Chapter 3.1.1. --- The yield of sclerotial polysaccharides --- p.61
Chapter 3.1.2 --- Total carbohydrate content of sclerotial polysaccharides --- p.65
Chapter 3.1.3 --- Protein content of sclerotial polysaccharides --- p.66
Chapter 3.1.4 --- Monosaccharide profiles of sclerotial polysaccharides from PR by gas chromatography (GC) --- p.66
Chapter 3.1.5 --- Molecular weight of sclerotial polysaccharides from PR by size exclusion chromatography (SEC) --- p.69
Chapter 3.1.6 --- Endotoxin test --- p.73
Chapter 3.2 --- Immune responses for human monocytic cell line THP-1 --- p.74
Chapter 3.2.1 --- MTT cell viability assay --- p.74
Chapter 3.2.2 --- BrdU cell proliferation assay --- p.75
Chapter 3.2.3 --- Change in cell morphology of THP-1 --- p.79
Chapter 3.2.4 --- Phenotypic maturation of THP-1 --- p.81
Chapter 3.2.5 --- Up-regulated phagocytic ability of THP-1 --- p.84
Chapter 3.2.6 --- Increased nitrite production in THP-1 --- p.86
Chapter 3.2.7 --- Production of reactive oxygen species --- p.88
Chapter 3.2.8 --- Human cytokines profile array --- p.90
Chapter 3.2.9 --- Cell cycle analysis --- p.93
Chapter 3.2.10 --- Surface receptors expression --- p.95
Chapter 3.2.11 --- Summary --- p.98
Chapter 3.3 --- Immune responses for murine immature BMDCs --- p.102
Chapter 3.3.1 --- Inhibition effects on murine immature BMDCs --- p.102
Chapter 3.3.2 --- Change in cell morphology of murine immature BMDCs --- p.103
Chapter 3.3.3 --- Phenotypic maturation of murine immature BMDCs --- p.105
Chapter 3.3.4 --- Down-regulation of endocytosis in murine immature BMDCs --- p.106
Chapter 3.3.5 --- Increased nitrite production --- p.109
Chapter 3.3.6 --- Decreased expression of CD 11c in PRW-treated immature BMDCs --- p.109
Chapter 3.3.7 --- Cytokine profile detection --- p.112
Chapter 3.3.8 --- Surface receptors expression --- p.116
Chapter 3.3.9 --- Summary --- p.119
Chapter Chapter 4 --- Conclusion and future works --- p.123
Appendix --- p.125
References --- p.126
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"Mushroom Sclerotial Polysaccharides and β-glucans from Other Sources: A Comparative Study of Their in vitro Immunomodulating Effects on Macrophages." 2016. http://repository.lib.cuhk.edu.hk/en/item/cuhk-1292138.

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源自菌菇的具有生物活性的多糖(含β-葡聚糖)能有效調節先天性免疫,早在二十世紀末就被應用于臨床。現有關於菌菇類β-葡聚糖的免疫調節活性以及其結構-活性之間的關係的研究相對匱乏,因此限制了臨床應用。巨噬細胞遍佈宿主的全身,是先天性免疫中主要的細胞。本研究將從藥用菌核虎乳靈芝(PR)中提取純化出具有新穎結構的多糖,并研究其對巨噬細胞的免疫活性。本研究亦試圖比較不同來源的β-葡聚糖在結構和活性方面的差異以更好地闡述其結構-活性的關係。
通過用熱水提取和冷鹼(1M NaOH)依次提取虎乳靈芝的多糖組分,得到水溶性組分(PRW) 和三種鹼溶性組分(PRA-1, PRA-2A和PRA-2C)。從這些組分中,PRW經過超濾純化得到新穎的糖蛋白複合物PRW1,顆粒化PRA-1(PRA-1p)也成功製備出。
PRW的多糖部分是由葡萄糖和甘露糖構成的雜多糖。PRW1分子量小於50 kDa,由45.7% 的雜多糖和44.2% 蛋白质構成的糖蛋白複合物。根據單糖組成,糖鏈結構,和紅外光譜分析的結果,PRW1的多糖部分b-D-mannoglucan由→1)-D-Glcp-(4→, →1)-D-Glcp-(6→ and →1)-D-Manp-(2→主鏈 (摩爾比例為5:4:6) 和末端D-Glcp支鏈構成 (分支度是0.62)。
PRA-1, PRA-2A和PRA-2C具有類似的化學結構,均為超多分枝 (1,3)-β-D-葡聚糖, 分枝位點在葡聚糖的O-6位,分支度分別是 0.89,0.87, 0.89。根據凝膠滲透色譜的結果,PRA-1, PRA-2A和PRA-2C 平均分子量為 24190, 28350 和 15950 kDa。掃描電鏡和透射電鏡的結果顯示,PRA-1p呈現均勻的球狀結構 (半徑範圍 0.5-1 微米),而PRA-1呈現棒狀結構 (長度範圍0.1-1 微米)。
非虎乳靈芝來源的β-葡聚糖中,大麥β-葡聚糖是通過b-(1,3)-(1,4)連接。羧甲基化curdlan (CM-curdlan), curdlan 和 pachyman 均是線性b-(1,3)-葡聚糖,laminarin和酵母葡聚糖均是由b-(1,3)主鏈和b-(1,6)支鏈構成,分支度分別是 0.3 和0.16。CM-curdlan, curdlan, 大麥β-葡聚糖, laminarin,pachyman和酵母葡聚糖的分子量依次是4378.6 kDa,3270.6 kDa,444.2 kDa,9.5 kDa,2.2 kDa,2.3 kDa。
體外免疫調節研究表示,PRA-1p, PRW and PRW1,CM-curdlan, curdlan and酵母葡聚糖能顯著激活鼠源性RAW264.7 巨噬細胞。
PRW1顯著增強RAW264.7中一氧化氮的產生,并引起RAW264.7形態改變。PRW1亦能刺激RAW264.7分泌細胞因子(包括G-CSF, GM-CSF, IL-6, IL12p40/70,MCP-1,MCP-5,MIP-1-α,MIP-2,RANTES,sTNFRI and TNF-α)。機制上來說,PRW1的處理在15分鐘內通過激活ERK來激活巨噬細胞,處理6小時后細胞內誘導性氧化氮合酶 (iNOS) 的表達顯著上調。
PRA-1p 能顯著增強RAW264.7中一氧化氮和活性氧的產生,引起RAW264.7形態改變,使細胞吞噬更多FITC標記的葡聚糖,表示了顯著提高巨噬細胞的吞噬能力。PRA-1p刺激RAW264.7顯著分泌更多細胞因子(包括CTACK,G-CSF,MCP-1,MIP-1α,MIP-2,RANTES,sTNFRI TIMP-1)。PRA-1p可能通過引起包括iNOS,NF-κB,ERK 和 AKT的活化,從而活化巨噬細胞。
CM-curdlan, curdlan 和 酵母葡聚糖能誘導人外周血單個核細胞分泌細胞因子(包括GM-CSF, GRO 和IL-6) 從而發揮免疫調節作用。
通過對比虎乳靈芝菌核多糖和非虎乳靈芝來源的葡聚糖在結構以及對小鼠巨噬細胞的免疫活性方面的差異,總結出b-(1,3)連接的葡聚糖較b-(1,3;1,4)連接的葡聚糖具有更強的免疫活性。對於b-(1,3)連接的葡聚糖,其線性結構和分枝結構以及分子量大小和水溶性都能影響葡聚糖對小鼠巨噬細胞的免疫活性。本研究亦揭示了顆粒結構對於增強b葡聚糖免疫活性的重要性。本研究為葡聚糖的結構免疫活性構效關係提供了重要的思路,並且為設計用於臨床的具免疫治療活性的b葡聚糖提供了方向。該研究中從虎乳靈芝菌核里提取的的新型糖蛋
Bioactive polysaccharides derived from mushrooms and fungi with b-glucans in particular are potent stimulants of innate immunity and have been used in clinical therapies since the late 20th century. The lack of detailed knowledge in the immunomodulating effects of b-glucans and their structure-activity relationship have limited their clinical applications. Macrophages, which are distributed throughout the body of the host, are the major effector cells of innate immunity. In this project, the sclerotia of a medicinal mushroom Polyporus rhinocerus (PR) was chosen from which novel structurally polysaccharides were isolated and purified and were used to study the immunomodulatory effect on macrophages. In order to delineate the structure-activity relationship, the macrophage activation by the PR mushroom polysaccharides with structural differences and b-glucans from other sources was compared in this project.
By differential solvent fractionation, a crude water-soluble fraction (PRW) and three alkali-soluble fractions (PRA-1, PRA-2A and PRA-2C) were obtained from the sclerotia of PR. Two specific samples from these fractions including a novel water-soluble polysaccharide-protein complex (PRW1) purified by membrane ultrafiltration from PRW using membrane ultrafiltration and a particulate form of PRA-1 (PRA-1p) were also prepared.
The polysaccharide moiety of PRW was a hyper-branched heteropolysaccharide which was composed of glucose and mannose. PRW1 had a molecular weight of less than 50 kDa and was found to be a highly branched heteropolysaccharide-protein complex with 45.7% polysaccharide and 44.2% protein. Based on the monosaccharide analysis, methylation study and Fourier transform infrared spectroscopy, the carbohydrate moiety of PRW1 was found to be a b-D-mannoglucan with its backbone containing →1)-D-Glcp-(4→, →1)-D-Glcp-(6→ and →1)-D-Manp-(2→ residues with a molar ratio of 5:4:6 and having terminal D-Glcp as side chain with a degree of branching of 0.62. PRA1 and PRA-2A and PRA-2C had similar structure which were hyper-branched β-glucans with a backbone composed of →1)-D-Glcp-(3→ linkages and side chains having the major branching points at the O-6 positions with a degree of branching of 0.89, 0.87 and 0.89, respectively. By gel permeation chromatograph (GPC), PRA-1, PRA-2A, PRA-2C were found to have an average molecular weight of 24190, 28350 and 15950 kDa,respectively. Results from scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that PRA-1 and PRA-1p had a spherical conformation with diameter ranging from 0.5-1 μm and a rod-like structure with length ranging from 0.1-1 μm, respectively.
The chemical structure of the b-glucans derived from non-PR sources was determined by methylation analysis. It was found that barley b-glucan was a linear b-(1,3)-(1,4)-glucan; carboxymethyl (CM)-curdlan, curdlan and pachyman were linear b-(1,3)-glucan while laminarin and yeast b-glucan were b-(1,6)-branched b-(1,3)-glucan with a DB of 0.3 and 0.16, respectively. The molecular weight of these non-PR b-glucans determined by GPC was as follows: 4378.6 kDa for CM-curdlan, 3270.6 kDa for curdlan, 444.2 kDa for barley b-glucan, 9.5 kDa for laminarin, 2.2 kDa for yeast b-glucan and 2.3 kDa for pachyman.
In vitro immunomodulatory studies showed that PRA-1p, PRW and PRW1, CM-curdlan, curdlan and yeast b-glucan significantly activated murine macrophage RAW264.7.
Specifically, PRW1 significantly induced nitric oxide (NO) production and stimulated morphological changes in RAW264.7 cells. PRW1 treatment enhanced the release of a variety of cytokines including G-CSF, GM-CSF, IL-6, IL12p40/70, MCP-1, MCP-5, MIP-1-
In addition, CM-curdlan, curdlan and yeast b-glucan exhibited immunomodulatory effects on human peritoneal blood mononuclear cells (PBMCs) by inducing cytokine production including GM-CSF, GRO, IL-6.
By comparing the structure and the in vitro immumomodulatory effect onmurine macrophges of PR polysaccharides and the non-PR β-glucans, it was confirmed that the β-(1,3)-glucans showed macrophage-activating effect while mixed linkage β-(1,3;1,4)-gluca
Liu, Chaoran.
Thesis Ph.D. Chinese University of Hong Kong 2016.
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