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  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Taxtomina A no controle dos vírus do mosaico do pepino e do mosaico amarelo em abobrinha de moita e da podridão mole (Rhizopus stolonifer) em uva / Thaxtomin A on the control of Cucumber mosaic virus (CMV) and Zucchini yellow mosaic virus (ZYMV) on zucchini squash and the rot (Rhizopus stolonifer) on grapes

Luiz Rafael Pinto 28 January 2014 (has links)
Existe uma crescente demanda por alternativas de controle de doenças para se reduzir o uso do controle químico, como por exemplo, o estudo da indução de resistência em plantas, através de fitotoxinas como a taxtomina A e outras substâncias. O vírus do mosaico do pepino (Cucumber mosaic virus - CMV) e o vírus do mosaico amarelo da abobrinha (Zucchini yellow mosaic virus - ZYMV) têm causado grandes prejuízos em culturas importantes, assim como o fungo Rhizopus stolonifer, que pode atacar diversos hospedeiros. Este trabalho foi conduzido com o objetivo de se avaliar os efeitos do uso da taxtomina A como indutor de resistência em plantas. Como resultado preliminar a produção de taxtomina A pode ser aumentada utilizando-se como fonte de inóculo amostra de uma cultura liquida pré-estabelecida de Streptomyces scabies. Foram testados a aspersão de taxtomina A em plantas de abobrinha de moita, para se avaliar a proteção contras os vírus CMV e ZYMV. Também foi aspergida taxtomina A em bagas de uva \"Itália\" para se avaliar o desenvolvimento da podridão pós-colheita causada por R. stolonifer. As plantas de abobrinha de moita, mantidas em casa de vegetação, tratadas com taxtomina A não apresentaram sintomas de mosaico característico do CMV. O teste ELISA apresentou resultados negativos indicando a não presença de partículas virais em níveis detectáveis nas plantas. Com relação ao ZYMV, a taxtomina A não foi capaz de controlar o desenvolvimento da doença, pois apareceram sintomas em todas as plantas. A taxtomina A apresentou efeito in vitro sobre R. stolonifer retardando o crescimento do fungo principalmente nas duas maiores concentrações usadas. Porém, a aplicação de taxtomina A não foi capaz de proteger as bagas de uva contra o patógeno. Finalizando a taxtomina A foi capaz de controlar em 100% a incidência de CMV em abobrinha, porém não foi capaz de controlar o ZYMV em abobrinha e a podridão nas uvas causada por R. stolonifer. / There is an increasing demand for alternative control of diseases to reduce the use of chemical control, for example the induced resistance studies on plants with phytotoxins like thaxtomin A and other substances. The Cucumber mosaic virus (CMV) and the Zucchini yellow mosaic virus (ZYMV) cause a lot of losses on important crops and also the fungus Rhizopus stolonifer that can cause disease in different hosts. This work was carried out to evaluate the use of thaxtomin A to induce resistance. Thus, as a preliminary result, the thaxtomin A production could be increased by using as inoculum an established Streptomyces scabies liquid culture. It was tested the spraying of thaxtomin A on zucchini plants to evaluate the protection against the viruses CMV e ZYMV. On the other hand, grape berries cv \"Italia\" were also sprayed with thaxtomin A to evaluate the development of the postharvest rot caused by R. stolonifer. The zucchini plants were maintained in the greenhouse and the treatment with thaxtomin A inhibited mosaic symptom development by the CMV. The ELISA test showed negative results indicating that there was no detectable virus particles inside the plants. The thaxtomin A was not able to control the ZYMV development since all plants exhibited symptoms. The thaxtomin A showed in vitro control of R. stolonifer as it reduced the fungal growing at the two highest concentrations used. However, the thaxtomin A was not able to control the postharvest rot in grapes. Finally, the thaxtomin A was able of controlling 100% of the incidence of CMV on zucchini plants, but was not able of controlling ZYMV in zucchini and the grape berrie rot caused by R. stolonifer.
132

Fosfito de potássio no controle de doenças pós-colheita em bagas de uva ´Itália´ e possíveis mecanismos de ação à Rhizopus stolonifer / Potassium phosphite on postharvest disease control in ´Itália´ grape berries and possible mode of action to Rhizopus stolonifer

Rafaela Carolina Constantino Roma 10 March 2014 (has links)
A ocorrência de doenças em uvas de mesa gera perdas desde o cultivo até a comercialização, o que afeta diretamente o potencial de exportação do Brasil. A prevenção na realização de injúrias nos frutos é essencial para garantir a eficácia dos tratamentos aplicados tanto em pré- quanto em pós-colheita. Visando o emprego de produtos alternativos que auxiliem no manejo sustentável da cultura, o fosfito de potássio encontra-se como ferramenta útil. O efeito do fosfito no controle de doenças causadas por oomicetos já foi relatado, porém, como este ingrediente ativo atua sobre microrganismos do reino Fungi ainda é desconhecido. Neste contexto, este trabalho teve como objetivo avaliar o fosfito de potássio no controle das doenças podridão mole, mofo cinzento e podridão da uva madura, causadas por Rhizopus stolonifer, Botrytis cinerea e Colletotrichum gloeosporioides, respectivamente, em bagas de uva ´Itália´ e seus efeitos na qualidade físico-química dos frutos. Também objetivou-se estudar os mecanismos de ação envolvidos na inibição do desenvolvimento do micélio de R. stolonifer na presença do produto e na indução de respostas de defesa em bagas de uva. Foram realizados ensaios in vitro para avaliação do efeito do fosfito sobre o crescimento micelial, esporulação e germinação dos esporos para R. stolonifer, B. cinerea e C. gloeosporioides. Experimentos utilizando-se de bagas foram conduzidos, visando avaliar o efeito no uso do fosfito como fungicida produtor ou curativo para os três patógenos. Cachos foram utilizados para se determinar os efeitos da aspersão do fosfito sobre a qualidade físico-química dos frutos. Para avaliação dos mecanismos de ação do fosfito sobre o micélio de R. stolonifer, foram determinados os efeitos sobre a permeabilidade da membrana plasmática, a síntese de parede celular e a síntese de proteínas. A atividade de guaiacol peroxidase e de compostos fenólicos totais foi determinada em bagas de uva tratadas ou não com fosfito. Houve inibição do crescimento micelial, da esporulação e da germinação dos esporos dos patógenos desenvolvidos em diferentes concentrações de fosfito de potássio. O tratamento protetor e curativo das bagas evidenciou reduções significativas na área abaixo da curva de progresso das doenças estudadas. Não houve efeito do produto sobre a qualidade físico-química dos cachos de uva. Quanto aos mecanismos de ação, foram observados efeitos do fosfito sobre a permeabilidade de membrana, devido à elevada perda de eletrólitos do micélio. O fosfito proporcionou elevação na síntese de proteínas totais no micélio do patógeno e redução na atividade de ?-1,3- glucanase e quitinase, que são enzimas relacionadas à síntese de parede. A atividade de guaiacol peroxidase e a concentração de compostos fenólicos totais não aumentou com a aplicação do fosfito nas bagas. Desta forma, pode-se concluir que o fosfito de potássio controlou a podridão mole, o mofo cinzento e a podridão da uva madura e não teve efeito sobre a qualidade físico-química dos frutos. Ainda, o fosfito atuou sobre a permeabilidade de membrana, síntese de proteínas e de parede celular do micélio de R. stolonifer e não proporcionou indução da atividade de guaiacol peroxidase e compostos fenólicos totais em bagas de uva. / The occurrence of table grape diseases causes losses from the field to the commercialization, which affects the Brazil potential to export. The prevention of injuries in fruits is essential to ensure the pre- and postharvest treatment efficiency. In order to use alternative products to support the crop sustainable management, phosphite may be a useful tool. The phosphite effect on control of diseases caused by oomycetes has been reported, however, how the active ingredient acts on microorganisms from the Fungi kingdom is unknown. Thus, the objective was to evaluate potassium phosphite on the control of soft rot, grey mold and ripe rot, caused by Rhizopus stolonifer, Botrytis cinerea e Colletotrichum gloeosporioides, respectively, in ´Itália´ grape berries and its effect on physico-chemical properties of the fruits. Moreover, the objective was to study the mode of action involved on the inhibition of R. stolonifer grown in the presence of phosphite and on the induction of defense responses in grape berries. In vitro assays were carried out to evaluate the effect of phosphite on mycelial growth, sporulation and spore germination in R. stolonifer, B. cinerea e C. gloeosporioides. Single berries were used in order to evaluate the effect of phosphite as a protective or curative fungicide against the three pathogens. Grape clusters were used to determine the effects of phosphite spraying on physico-chemical properties. To evaluate the mode of action of phosphite on R. stolonifer mycelium the plasma membrane permeability, the protein synthesis and the cell wall synthesis were monitored. The guaiacol peroxidase activity and phenolic compound concentration were evaluated in grape berries treated or not with phosphite. There were inhibition on mycelial growth, sporulation and spore germination on the three pathogens in different potassium phosphite concentrations. The protective and curative treatment in grape berries showed significant reductions on the area under disease progress curve of the studied diseases. There was no effect on physico-chemical properties of the grapes. Regarding the mode of action, the phosphite affected membrane permeability what was seen as high electrolyte leakage from the mycelium. Phosphite caused high protein synthesis in the mycelium and reduction on ?-1,3-glucanase and chitinase activities, which are enzymes related to cell wall synthesis. The guaiacol peroxidase activity and phenolic compound concentration did not increase due the phosphite application. Thus, it may be concluded that potassium phosphite controlled soft rot, grey mold and ripe rot in grape berries and did not affect the physico-chemical properties of the fruits. Besides that, phosphite still acted on membrane permeability, protein synthesis and cell wall synthesis on the R. stolonifer mycelium and did not changes in guaiacol peroxidase activity and phenolic compound concentration in the grape berries.
133

Caracterização físico-química de vinhos em diferentes regiões do Rio Grande do Sul / Physico-chemical characterization of wines from different regions of Rio Grande do Sul

Lúcio, Priscila da Silva 10 April 2015 (has links)
Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2016-09-28T12:54:54Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) DISSERTAÇAO PRONTA PRISCILA.pdf: 1224969 bytes, checksum: 6099db0950fec2d077f81a89a4cd88b7 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2016-09-28T17:21:28Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) DISSERTAÇAO PRONTA PRISCILA.pdf: 1224969 bytes, checksum: 6099db0950fec2d077f81a89a4cd88b7 (MD5) / Made available in DSpace on 2016-09-28T17:21:28Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) DISSERTAÇAO PRONTA PRISCILA.pdf: 1224969 bytes, checksum: 6099db0950fec2d077f81a89a4cd88b7 (MD5) Previous issue date: 2015-04-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / As características dos vinhos provem do terroir de cada região combinados com os processos enológicos, dando origem a vinhos exclusivos e com características próprias. O Rio Grande do Sul hoje é o maior produtor de uva e vinho do país, sendo o Brasil o 13º em produção de vinho. Este trabalho teve por objetivo a caracterização de vinhos provenientes das regiões e vinícolas da Serra Gaúcha, Campanha Gaúcha, Fronteira Oeste e Centro do Rio Grande do Sul, onde foram realizadas análises físico-químicas: etanol, pH, fenóis e ácido tartárico no equipamento wineScan na Universidade UNIPAMPA. Já os parâmetros de cor obtidos através da absorbância dos comprimentos de onda 420nm, 520nm, 620nm, índice de polifenóis totais (D280nm), índice de cor e tonalidade foram quantificados no laboratório de Agronomia (LabAgro) da Universidade Federal de Pelotas (UFPel). As amostras foram coletas de vinhos já elaborados de Vitis viniferas tintas das variedades Merlot, Cabernet Sauvignon e Tannat, e das variedades brancas, Riesling Itálico e Chardonnay. Para vinhos da variedade Cabernet Sauvignon destacamos a Fronteira Oeste com valores de fenóis 67,62 gLˉ¹, dentre as vinícolas destaca-se a vinícola “CV’’ com etanol 13,60% v/v e a vinícola ”SB’’ com o índices de polifenois totais 23,10. Os vinhos Merlot a região da Fronteira Oeste destacou-se com fenóis 78,39 gL ¹. As vinícolas ”MV” com etanol 13,07% v/v, e a vinícola “VM” com fenóis de 79,32 gLˉ¹. A região da Serra Gaúcha destaca-se para os vinhos Tannat com etanol 8 13,20% v/v, as vinícolas “L” com o índice de polifenois totais 29,50 e a vinícola “G” com 61,42 gLˉ¹ de fenóis. Os vinhos Riesling Itálico a região da Serra Gaúcha se mostrou superior em relação ao etanol com 10,94% v/v. A vinícola “P” destacou-se com etanol de 10,94 v/v%, e a vinícola “MV” com fenóis de 20,65 gLˉ¹. Os vinhos Chardonnay destaca-se a Campanha com etanol 12,98, fenóis. Destaque para os vnhos produzidos na vinícola “BS” com etanol de 13,71 v/v%, fenóis 35,72 gLˉ¹ e vinícola “DL” obteve absorbância 420nm que representa a cor amarela em 1,131. Palavras-chave: Vitis vinifera, Vitivinicultura, Vinícola, Físico-químico, Cor. / The characteristics of the wine comes terroir of each region combined to the winemaking process, giving rise to wines with unique characteristics. The Rio Grande do Sul is now the largest grape grower and wine country, and Brazil is the 13th in wine production. This study aimed to characterize wines from the regions and wineries in Serra Gaucha, Gaúcha Campaign, Western Border and Rio Grande do Sul Center, where physicochemical analyzes were performed: ethanol, pH, phenols and tartaric acid in Winescan equipment at the University UNIPAMPA. As for the color parameters obtained by absorbance of wavelengths 420nm, 520nm, 620nm, total polyphenol index (D280nm), color index and pitch were quantified in Agronomy Lab (LabAgro) of the Federal University of Pelotas (UFPel). Samples were collected wine already prepared in Vitis vinifera paints of Merlot varieties, Cabernet Sauvignon and Tannat, and white varieties, Riesling Italico and Chardonnay. For wines from Cabernet Sauvignon highlight the Frontier West with phenol values gLˉ¹ 67.62, among the wineries there is the wine "CV '' with ethanol 13,60% v / v and the winery" SB '' with the index total polyphenols 23.10. The Merlot wines of the region West Frontier stood out with phenols 78.39 g L ¹. The wineries "MV" with ethanol 13.07% v / v, and the winery "VM" with 79.32 gLˉ¹ phenols. The region of Serra Gaucha stands out for Tannat wines with ethanol 13.20% v / v, the wineries "L" with the index of total polyphenols 29.50 and the "G" winery with 61.42 gLˉ¹ phenols. The Riesling Italic wines the Serra Gaucha was superior in relation to ethanol with 10.94% v / v. The wine "P" highlighted with 10.94 v / v% ethanol, and wine "MV" 20.65 gLˉ¹ with phenols. The Chardonnay wines highlight the campaign with ethanol 12.98, phenols. Highlighting the vnhos produced in winery "BS" with ethanol 13.71 v / v%, phenols 35.72 gLˉ¹ and wine "DL" got 420nm absorbance representing the color yellow in 1,131.
134

Mejoramiento de la pigmentación de bayas de vid de la variedad crimson seedless mediante la aplicación de ácido abscísico y ethephon

Santander Rojas, Marcela Fernanda January 2011 (has links)
Memoria para optar al Título Profesional de Ingeniero Agrónomo Mención: Fruticultura / Con el fin de evaluar el efecto de la aplicación de ácido abscísico (ABA) y ethephon sobre el contenido de antocianos y color en bayas de la variedad de uva de mesa Crimson seedless, se realizó este ensayo durante la temporada 2008/2009 en un parrón perteneciente a Agrícola Santa Marta, Fundo Santa Inés, ubicado en Huelquén, comuna de Buin. Se utilizaron plantas de 6 años de edad, aplicando en envero. Los tratamientos fueron seis: ABA a 150 mg/L y 200 mg/L, ethephon a 200 mg/L, ABA más ethephon a 150 más 100 mg/L y a 200 más 100 mg/L, respectivamente, y un tratamiento control. Se midieron semanalmente parámetros de calidad como: diámetro ecuatorial de bayas, acidez titulable, sólidos solubles, firmeza y color de las bayas, desde que estas presentaron un promedio de 15,5 mm hasta la cosecha de la fruta. En la cosecha de la fruta se evaluaron siete parámetros adicionales: diámetro polar de bayas, contenido de agua, peso de bayas, tamaño del racimo, peso del racimo, peso del raquis y contenido de antocianos en la epidermis de las bayas. Los resultados mostraron que la aplicación de los productos ensayados afectó el contenido de antocianos, el color y los sólidos solubles de las bayas, sin modificar los otros parámetros analizados. Todos los tratamientos aumentaron el contenido de antocianos en sus bayas respecto del control, pero los tratamientos que mostraron el mayor aumento fueron los con ABA más ethephon a concentraciones de (150 + 100 mg/L) y (200 + 100 mg/L), y el tratamiento con sólo ethephon. Por otra parte, se observó que sólo la aplicación combinada de ABA más ethephon aumentó la coloración de las bayas en comparación al testigo. El momento de pinta o envero en la variedad de uva de mesa Crimson seedless ocurrió 29 días antes de cosecha. / In order to evaluate abscisic acid (ABA) and ethephon application effect on berry anthocyanin content and color of “Crimson seedless” table grapes, a trial was carried out in Agrícola Santa Marta, in Santa Ines’ vineyard located in Huelquén, Buin. Treatments were applied at veraison to six-year-old grapevines. There were six treatments: ABA at 150 mg/L and 200 mg/L, ethephon at 200 mg/L, ABA plus ethephon at 150+100 mg/L and at 200 + 100 mg/L, respectively, and an untreated control. Thus, weekly quality parameters were measured: berry diameter, juice titratable acidity, soluble solids, berry firmness and color, from berry sice was 15,5 mm until harvest. Additionally, at harvest, seven other parameters were measured: berry length and weight, water content, cluster size and weight, rachis weight and anthocyanin content. Results showed that assayed products affected berry anthocyanin content, color and soluble solids, without modifying further parameters analyzed. In all treatments, anthocyanin contents increased compared to the untreated control, but ABA plus ethephon treatments in concentrations of (150 + 100 mg/L) y (200 + 100 mg/L), and only ethephon treatment showed the highest anthocyanin content. Besides, only the combined application of ABA plus ethephon improved berry color compared to untreated berries.
135

Étude du rôle des stilbènes dans les défenses de la vigne contre les maladies du bois / Role of stilbenoid compounds in grapevine defence against trunk diseases

Lambert, Carole 15 December 2011 (has links)
Les maladies du bois de la vigne, par exemple le syndrome de l’esca et l’eutypiose, sont dues à des champignons qui se développent dans le xylème et dégradent les tissus ligneux. Elles sont en recrudescence depuis une vingtaine d’année dans tous les vignobles du monde. A ce jour, aucun traitement curatif n’est disponible alors que ces maladies engendrent généralement la mort de la plante. L’étude des relations hôte-parasite et notamment celle des réponses de défense de plante, est nécessaire pour la compréhension et le développement de nouvelles stratégies de lutte. Parmi les molécules de défense de la vigne, les stilbènes sont connus pour leur forte activité antifongique.Notre travail, basé sur des approches biochimiques et moléculaires apporte de nouvelles données sur le rôle potentiel des stilbènes en tant que molécules de défense contre les maladies du bois. Nous avons identifié et quantifié les stilbènes majoritaires des tissus ligneux de V. vinifera, évalué la sensibilité des agents de maladie du bois à l’effet antifongique de ces stilbènes et suivi leur éventuelle induction suite à l’inoculation d’agents de maladie du bois. Nous avons souligné l’importance des oligomères de stilbènes dont l’activité antifongique est élevée et montré qu’ils sont fortement induits dans le bois inoculé par un champignon pathogène de la famille des Botryosphaeriaceae. La comparaison des réponses de défenses entre des cépages tolérants et sensible, a montré que les cépages tolérants répondent globalement plus fortement et plus rapidement que le cépage sensible à une élicitation par un filtrat de milieu de culture d’un agent de l’esca. / Grapevine wood diseases, as esca syndrome and eutypiosis, are worldwide afflictions. They are due to xylem inhabiting fungi that cause the decay of woody tissues and finally the death of the plant. No curative treatment has been successfully developed until now. Studying grapevine-wood disease pathogen interaction is a prerequisite to the development of protection strategies. Phenolics, particularly stilbenoids, are antimicrobial molecules involved in the resistance of grapevine to fungal pathogens. Our work, based on biochemical and molecular approaches, reveals new data on the possible role of stilbenoids in grapevine defence against trunk diseases. We identified and quantified major stilbenoids of woody canes from V. vinifera. These compounds, especially stilbenoid oligomers, displayed in vitro antifungal activity against trunk disease agents and were induced in cuttings inoculated with an agent of the Botryosphaeriaceae family. We also compared the defence response of susceptible or tolerant cultivars to wood decay based on an elicitation assay with a culture filtrate of an esca pathogen. Defence responses of tolerant cultivars were more effective than those of the susceptible cultivar.
136

Formação de micro e minijardim clonal de videira / Formation of micro and miniclonal grapevine garden

Nascimento, Daniele Camargo 22 October 2018 (has links)
Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2018-11-22T11:34:13Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese - Daniele Nascimento.pdf: 2307979 bytes, checksum: fae15660c3467f912386c461f7c5a2bb (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-11-23T18:48:09Z (GMT) No. of bitstreams: 2 Tese - Daniele Nascimento.pdf: 2307979 bytes, checksum: fae15660c3467f912386c461f7c5a2bb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-11-23T18:48:09Z (GMT). No. of bitstreams: 2 Tese - Daniele Nascimento.pdf: 2307979 bytes, checksum: fae15660c3467f912386c461f7c5a2bb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-10-22 / A obtenção de mudas de qualidade é o primeiro passo para a garantia de um vinhedo duradouro e com bom potencial de produção. Para isso, é necessário a aplicação de técnicas e o desenvolvimento de sistemas que otimizem o processo de produção de mudas. Neste sentido, os objetivos deste estudo foram: desenvolver um protocolo de micropropagação de videira (incluindo as etapas de multiplicação, enraizamento e aclimatização), a formação de um micro e um minijardim clonal e a avaliação destes em sistema de cultivo convencional e cultivo sem solo. O estudo foi desenvolvido por meio de cinco experimentos conduzidos no Laboratório de Botânica e no viveiro de mudas pertencentes à Universidade Federal do Pampa, Campus Dom Pedrito, RS. Primeiramente, foram realizados experimentos de multiplicação e enraizamento in vitro, em laboratório. Nestes experimentos foram testados o meio de cultura MS (Murashige & Skoog) com a concentração completa de sais (MS) e com a metade da concentração de sais (MS/2), concentrações de BAP (0, 5 e 10μM) para a multiplicação e concentrações de AIB (0; 0,1; 0,2; 0,3mg L1) para o enraizamento in vitro de explantes de videira Chardonnay. Logo, estas plântulas produzidas por micropropagação foram aclimatizadas no viveiro de mudas, testando-se as seguintes composições de substratos: HDecker®; HDecker® + vermiculita; HDecker® + fibra de coco; HDecker® + Humosolo ES®; vermiculita + Humosolo ES®; vermiculita + fibra de coco; Humosolo ES® + fibra de coco. Todas as combinações de substratos foram formuladas na proporção 1:1. Paralelamente, foram produzidas mudas por meio da técnica de miniestaquia, sendo avaliado o enraizamento de miniestacas herbáceas de videira Chardonnay e SO4 sem o uso de AIB e com as concentrações de 500, 1000 e 1500mg L-1. Após a obtenção de mudas produzidas por micropropagação e por miniestaquia, as mudas de Chardonnay foram utilizadas para a formação dos jardins clonais, sendo avaliado o crescimento dessas mudas nos sistemas de cultivo convencional e cultivo sem solo. Nas etapas de multiplicação e enraizamento in vitro, as concentrações do meio de MS não tiveram efeito significativo para a maioria das variáveis, podendo ser utilizado completo ou com a metade da concentração dos sais. Para multiplicação, recomenda-se o uso 10μM de BAP e, para o enraizamento, é indicado o uso de 0,1 mg L-1 de AIB. Já na etapa de aclimatização, os substratos que continham vermiculita na composição, apresentaram melhores resultados. Na miniestaquia, as miniestacas herbáceas de Chardonnay e SO4 enraizaram mesmo sem o uso de regulador de crescimento. Para a formação de jardins clonais, tanto as mudas micropropagadas, quanto as obtidas por miniestaquia podem ser utilizadas. O sistema de cultivo sem solo mostrou-se eficiente para o crescimento de mudas de Chardonnay, sendo superior ao sistema convencional de cultivo. / Obtaining quality plantlets is the first step in ensure a lasting vineyard with good production potential. For this, it is necessary the application of techniques and the development of systems that optimize the process of plant production. In this sense, the objectives of this study were: to develop a micropropagation protocol for grapevine (including multiplication, rooting and acclimatization stages), the formation of a micro and minigarden clonal, and the evaluation of these in a conventional system of cultivation and cultivation soilless. The study was developed through five experiments conducted in the Botany Laboratory and in the nursery belonging to the Federal University of Pampa, Campus Dom Pedrito, RS. First, in vitro multiplication and rooting experiments were carried out in the laboratory. In these experiments we tested the MS culture media (Murashige & Skoog) with the full concentration of salts (MS), and with half the concentration of salts (MS/2), BAP concentrations (0, 5 and 10μM) to the multiplication and concentrations of IBA (0; 0.1; 0.2; 0.3mg L-1) for the in vitro rooting of Chardonnay grapevine explants. After, these plantlets produced by micropropagation were acclimatized in the nursery, testing the following compositions of substrates: HDecker®; HDecker® + vermiculite; HDecker® + coconut fiber; HDecker® + Humosol ES®; vermiculite + Humosol ES®; vermiculite + coconut fiber; Humosolo ES® + coconut fiber. All combinations of substrates were formulated in a 1:1 ratio. In parallel, plantlets were produced by minicutting technique, being evaluated the rooting of herbaceous minicuttings of Chardonnay and SO4 grapevine without the use of IBA and with concentrations of 500, 1000 and 1500mg L-1. After obtaining plantlets produced by micropropagation and minicutting, the Chardonnay plantlets were used for the formation of clonal gardens, where the growth of these plantlets was evaluated in the systems of conventional cultivation and soilless cultivation. In the in vitro multiplication and rooting stages, the concentrations of the MS culture media did not have a significant effect for most of the variables, being able to be used in whole or with half the concentration of salts. For multiplication, it is recommended to use 10μM of BAP and, for rooting, is indicated the use of 0.1 mg L-1 of IBA. Already in the acclimatization stage, the substrates that contained vermiculite in the composition, presented better results. In minicutting, the herbaceous minicuttings of Chardonnay and SO4 rooted even without the use of growth regulator. For the formation of clonal gardens, both micropropagated plantlets and minicutted plantlets can be used. The soilless cultivation system was efficient for the growth of Chardonnay plantlets, being superior to the conventional cultivation system.
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Evaluación in vitro de antagonistas sobre cepas seleccionadas de Cylindrocarpon macrodidymum Halleen, Schroers & Crous, agente causal de la enfermedad del pie negro de la vid (Vitis vinifera L.) / Evaluation of antagonists over selected strains of Cylindrocarpon macrodidymum Halleen, Schroers & Crous, causal agent of blackfoot disease on grapevines (Vitis vinifera L.)

Pinto Veas, Gabriel Francisco January 2014 (has links)
Memoria para optar al título profesional de: Ingeniero Agrónomo, mención Sanidad Vegetal / Cylindrocarpon macrodidymum es uno de los fitopatógenos causantes de la enfermedad del pie negro en la vid. La reducción del cuidado sanitario, los cambios en los manejos culturales y la baja efectividad de algunos fungicidas químicos, ha obligado a buscar nuevas alternativas de control que no estén limitadas por las condiciones ambientales, ecológicas y económicas, abriendo una ventana para técnicas alternativas de control, tales como el control biológico. En el presente trabajo, se evaluó el efecto biocontrolador in vitro de 12 cepas fúngicas antagonistas y 9 cepas bacterianas antagonistas, sumado a dos productos comerciales, sobre tres cepas seleccionadas de Cylindrocarpon macrodidymum aisladas de los valles de Copiapó y Huasco. Estas fueron caracterizadas en función de su pH y temperatura óptima de crecimiento, determinando que el pH óptimo de crecimiento se encontraba entre 5,7 y 7,7, mientras que la temperatura óptima fue 25ºC. Estos valores se utilizaron para las evaluaciones realizadas. Para cada combinación antagonista-fitopatógeno, se realizaron ensayos de antagonismo directo, mediante cultivos duales y de metabolitos difusibles de los biocontroladores sobre las tres cepas de C. macrodidymum. Todos los antagonistas fungosos y bacterianos utilizados, ejercieron algún grado de inhibición del crecimiento radial de las cepas de C. macrodidymum evaluadas, tanto en los ensayos de antagonismo directo como en los de metabolitos difusibles. La cepa Trichoderma 84a, fue aquella que obtuvo un mayor porcentaje de ICR promedio en los ensayos de antagonismo directo con hongos (81.5%), mientras que el producto comercial en base a Streptomyces lydicus WYEC108, fue aquel que obtuvo el mayor porcentaje de ICR promedio en los ensayos de antagonismo directo con bacterias (96.1%). En los ensayos de metabolitos difusibles, no existieron diferencias en los porcentajes de ICR para ninguno de los antagonistas fungosos evaluados, mientras que en los ensayos de metabolitos difusibles con bacterias, nuevamente el producto comercial en base a Streptomyces lydicus WYEC108, fue el que obtuvo un mayor porcentaje de ICR promedio (100%). / Cylindrocarpon macrodidymum is a phytopathogen fungi that has been associated with black foot disease of grape vines in Chile. Lack of sanitary measures, changes of cultural methods and low agrochemical efficacy, are forcing to seek out for new control alternatives that are not limited by enviromental, ecological or economic conditions, thus leading to new ways of fungi disease management, such as biological control. The in vitro biocontrol efficacy of 12 antagonic fungi strains, 9 antagonic bacterial strains and two commercial biological control products were tested against three previously selected C. macrodidymum strains. These strains, isolated from Copiapó and Huasco valleys, were characterised by their optimal growth pH and temperature, establishing their optimal growth pH between 5,7 and 7,7 and their optimal growth temperatura at 25ºC. These values were used for the antagonistic trials. For each antagonist-pathogenic variant, antagonistic capacity of each antagonist was tested on dual cultures and diffusible metabolite efficacy trials against the pathogenic strains. Commercial biological control products, bacterial strains and fungi strains were all capable of inhnibiting the radial growth of the three C. macrodidymum strains. In dual culture trials, Trichoderma 84a strain had the highest average inhibitory effect (81.5%). Commercial biocontrol product, based on Streptomyces lydicus WYEC108 bacterial strain, had the highest inhibitory control in bacterial trials (96.1%). No significant differences were shown in the fungi trials for diffusible metabolites efficacy. Commercial biocontrol product, based on Streptomyces lydicus WYEC108 had the highest inhibitory effect in diffusible metabolite trials (100%).
138

Evaluación de la aplicación de tidiazurón sobre el área foliar del brote y tamaño de baya en uva de mesa var. Flame seedless

Briceño Pinto, Matías January 2014 (has links)
Tesis presentada como parte de los requisitos para optar al Título Profesional de Ingeniero Agrónomo y al Grado de Magíster en Ciencias Agropecuarias, Mención Producción Frutícola / Este trabajo tuvo como objetivo evaluar el efecto de tidiazurón (TDZ) sobre el desarrollo del área foliar de brotes de vides ‘Flame Seedless’, ubicadas en un huerto comercial en la localidad de El Tránsito, Provincia del Huasco, Región de Atacama, Chile. Se realizaron aplicaciones de TDZ en precuaje, en distintos largos de brote (15, 30 y 45 cm), utilizando el producto comercial Splendor® (5% p/v SC, Bayer CropScience). En el ensayo se establecieron 4 tratamientos, aplicados en plantas con igual nivel de producción, 20 racimos por planta. Todas las aplicaciones tuvieron una concentración de 1,5 mg·L-1 de TDZ. El tratamiento control (T0), correspondió a plantas sin aplicación de TDZ; T1 a plantas con 3 aplicaciones de TDZ (15, 30 y 45 cm de largo de brote) y con dosis de producto de 126 mL· ha-1 ; T2 a plantas con aplicación de TDZ en 2 oportunidades (15 y 30 cm de largo de brote) y con dosis de producto de 84 mL· ha-1 ; y T3 a plantas con aplicación de TDZ en largo de brote de 15 cm y con dosis de producto de 42 mL· ha-1 . En las aplicaciones se utilizó un mojamiento de 1400 L·ha-1 , utilizando barra pulverizadora. La aplicación de TDZ, en 3 momentos de largo de brote (T1), fue capaz de incrementar el área foliar del brote (2.774 cm2 ) al compararla con vides sin aplicación (1.919 cm2 ). El análisis de componentes principales mostró una fuerte asociación entre T1 y el número de hojas totales en el brote, el número y largo de entrenudos y el número de feminelas en brote. Todas las aplicaciones de TDZ disminuyeron el porcentaje de racimos en la categoría de calibre comercial más baja (S), de un 70 a un 20%. Pero no lograron incrementar el porcentaje de racimos en las categorías más altas. T1 produjo un raquis con mayor peso, mayor grosor en el eje y hombros, y menor flexibilidad. / The objective of this study was to evaluate the effect of thidiazuron (TDZ) on leaf area development of shoots of 'Flame Seedless' vines, located in a commercial vineyard in El Transito, Huasco Province, Atacama Region, Chile. TDZ was applied at pre fruit set, at various shoot lengths (15, 30 and 45 cm), using the commercial product Splendor ® ( 5% w/v CS, Bayer CropScience ). Four treatments were established, applied to plants with the same production level, 20 clusters per plant. All applications had a concentration of 1.5 mg·L-1 TDZ. Control treatment (T0) corresponded to plants without the application of TDZ; T1, plants with three applications of TDZ (15, 30 and 45 cm of shoot length) and product dose of 126 mL· ha-1 ; T2, plants with TDZ application at two occasions (15 and 30 cm of shoot length) and product dose of 84 mL· ha-1 , and T3, plants with TDZ application at shoot length of 15 cm and product dose of 42 mL· ha-1 . Spray volume used for applications was 1400 L·ha- 1 , with an airblast sprayer. TDZ application at three times of shoot length (T1) increased total leaf area of shoot (2774 cm2 ) compared to vines with no application (1919 cm2 ). The principal component analysis showed a strong association between T1 and total shoot leaf number, the number and length of internodes and number of lateral shoots. All TDZ applications decreased the percentage of clusters in the lower commercial size category (S), 70 to 20%. But TDZ treatments failed to increase the percentage of clusters in the higher categories. T1 produced rachis with greater weight and thickness, greater shoulders thickness and decreased flexibility
139

Polycyclic Aromatic Hydrocarbons (PAHs) iIn the Diep And Plankenburg Rivers and potential remediation using charred Vitis vinifera (GRAPE) leaf litter

Awe, Adetunji Ajibola January 2019 (has links)
Thesis (DPhil (Chemistry))--Cape Peninsula University of Technology, 2019 / Occurrence of polycyclic aromatic hydrocarbons (PAHs) in freshwater systems may aggravate the water crisis currently being experienced in the Western Cape province of South Africa. However, there is dearth of data on the levels of PAHs, necessary for effective assessment of water quality as well as remediation strategies. This study therefore assessed levels of PAHs in two important freshwater systems in the Western Cape Province, South Africa. The potential of grape leaf litter for PAH abatement was also investigated. A solid-phase extraction - gas chromatography - flame ionisation detection (SPE-GC-FID) method was developed to simultaneously determine the 16 United States Environmental Protection Agency (US EPA) priority PAHs in environmental samples. Levels of 16 US EPA priority PAHs were assessed in water, sediment and plants from seven selected sites on the Diep and Plankenburg Rivers. Seasonal variations of some water quality parameters and PAHs levels in water and sediment samples were determined from the selected sites. Activated carbons produced from Vitis vinifera (grape) leaf litter were utilised for PAH-remediation. The SPE-GC-FID method developed for the 16 US EPA priority PAHs determination gave acceptable linearity (R2 > 0.999). Instrument detection limits ranged between 0.02 and 0.04 µg/mL and instrument quantification limits of between 0.06 and 0.13 µg/mL. Recovery studies were also acceptable (70.35 - 100.83%) with the exception of naphthalene that had lower recoveries. The average ∑16 PAHs detected in water samples at a given site, over a one-year period ranged from 73.90 to187.11 µg/L. The highest PAHs levels were detected in water samples from industrial areas of both rivers; chrysene (Chy) followed by benzo[a]anthracene (BaA) were the most abundant PAHs detected in water samples. Higher PAHs levels were detected in sediment samples relative to water samples; the average ∑16 PAHs detected in sediment samples at a given site, over a one-year period ranged from 6.048 to 39.656 µg/g. PAHs levels were also highest in sediment samples from industrial areas of the two rivers; benzo[b]fluoranthene (BbF) followed by benzo[k]fluoranthene (BkF) were the most abundant PAHs detected in sediment samples. The average ∑16 PAHs detected in plant samples [Phragmites australis (common reed) and Eichhornia crassipes (water hyacinth)] at a given site, ranged between 62.11 and 226.72 µg/g. Highest levels of PAHs were therefore detected in plant samples, suggesting possible bioaccumulation of PAHs in plant tissues. The bioaccumulation of PAHs by the plants also indicates the phytoremediation potential of these plants for PAHs remediation. The levels of PAHs measured in water and sediment samples were subjected to probabilistic risk assessment to predict the possibility of regulatory values being exceeded. The average percentage exceedence of 63.26 and 42.81 were obtained for PAHs in water samples of the Diep and Plankenburg Rivers respectively, while the corresponding average percentage exceedence obtained for sediment samples were 63.71 and 77.20. Vitis vinifera (grape) leaf litter showed enormous prospect as precursor for activated carbon. The yield of activated carbons obtained from grape leaf litter ranged from 44.65 to 58.40% and the Brunauer-Emmett-Teller (BET) surface area of up to 616.60 m2/g was obtained for activated carbons. The estimated adsorption capacities of the ZnCl2 and H3PO4 activated carbons for phenanthrene removal from aqueous solutions were 94.12 and 89.13 mg/g respectively. The environmental samples analysed were heavily contaminated with the 16 US EPA priority PAHs and the probabilistic risk assessment suggested risks of the carcinogenic PAHs at the levels measured in the environment. Vitis vinifera leaf litter, showed enormous potential as renewable precursor for activated carbon production, capable of removing varied contaminants from wastewater.
140

Comportement de Scaphoideus titanus, conséquences spatiales et démographiques / Scaphoideus titanus behaviour, spatial and demographic consequences

Chuche, Julien 08 December 2010 (has links)
La Flavescence dorée est une maladie à phytoplasme incurable qui affecte la vigne. Cette pathologie est uniquement transmise de plante à plante par la cicadelle vectrice Scaphoideus titanus. Malgré l'importance de cette maladie, peu d'études ont été menées sur le vecteur. Ce travail de thèse vise à apporter des connaissances sur la biologie et l'écologie de S. titanus mais aussi de manière plus générale sur l'écologie des insectes phytophages. Trois grands thèmes ont été abordés dans ce mémoire : i) les relations entre l'insecte et son environnement à travers l'influence des températures hivernales sur les œufs en diapause, ii) les relations de l'insecte avec sa plante hôte en examinant l'attractivité de cette dernière et le comportement alimentaire du vecteur, iii) les interactions entre congénères par l'étude du comportement d'agrégation des larves. Les résultats obtenus indiquent que 1) des températures froides ne sont pas indispensables à la levée de diapause mais affectent la protandrie en régulant le sex-ratio opérationnel, 2) l'attractivité de la plante hôte est en grande partie liée à sa couleur et il existe des différences de comportement en fonction du stade de développement, 3) les mâles et les femelles n'ont pas le même comportement alimentaire, ce qui pourrait expliquer leur différentes capacités de vection, 4) l'agrégation des larves ne semble pas due à un recrutement actif de leur part et pourrait contribuer à un transfert horizontal de phytoplasme d'insecte à insecte via la plante. A terme, ces connaissances pourront contribuer à l'élaboration de pistes alternatives à la lutte chimique actuelle contre cette cicadelle dans le cadre d'une réduction des intrants. / The Flavescence dorée is an incurable phytoplasma disease of grapevine. This pathology is exclusively transmitted from plant to plant by the leafhopper vector Scaphoideus titanus. Despite the importance of this disease, few studies have been conducted on the vector. This thesis aims to provide knowledge on the biology and ecology of S. titanus but also more broadly on the ecology of phytophagous insects. Three major themes were addressed in this thesis: i) the relationships between the insect and its environment through the influence of winter temperatures on diapausing eggs, ii) the relationships of the insect with its host plant by examining the attractiveness of the plant and the feeding behaviour of the vector, iii) interactions between congeners in the study of the aggregative behaviour of larvae. Our results indicate that 1) cold temperatures are not essential to break the diapause but contribute to protandry through operational sex ratio regulation, 2) the attractiveness of the host plant is largely due to its colour and different instars exhibit differences in behavioural choices, 3) males and females have different feeding behaviour which may explain their different efficiencies at vection, 4) the aggregation of larvae did not seem to result from active recruitment and could contribute to horizontal insect to insect transfer of phytoplasma through the plant. Such knowledge can contribute to the development of alternative S. titanus pest management techniques.

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