Thesis (Ph. D.)--University of Wisconsin--Madison, 1962. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

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Angl. resumé

Made available in DSpace on 2015-04-09T12:28:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-10-02Bitstream added on 2015-04-09T12:48:05Z : No. of bitstreams: 1 000812628.pdf: 353916 bytes, checksum: 6d0568f0705bfbe7f196964cf7d7147b (MD5) / As cercosporioses na cultura do amendoim são responsáveis por importante dano econômico. Representadas pela mancha castanha causada por Cercospora arachidicola e a mancha preta causada por Cercosporidium personatum, as cercosporioses podem acarretar perdas de produção na cultura do amendoim entre 50 a 70%. Dentre as medidas de controle destacam-se o uso de fungicidas de contato e sistêmicos. Atualmente são empregadas pulverizações pré-estabelecidas, espaçadas entre 14 -15 dias, iniciando-se a partir dos 20-30 dias após a emergência das plantas. O pré-estabelecimento das aplicações tem gerado inúmeros problemas, relacionados ao mal posicionamento e uso dos fungicidas, como aplicações em momentos inadequados, ou ausência em momentos fundamentais para o controle das doenças. Nesse estudo foi avaliado a eficiência e número mínimo de aplicações de fungicidas no controle das cercosporioses da cultura do amendoim. Para tal, foram avaliados os fungicidas clorotalonil, epoxiconazol + piraclostrobina nas dosagens 4 mL e 2,4 mL/L, aplicados em intervalos de 15 dias, em condições de campo, em plantios localizados em Jaboticabal e Ibitinga, estado de São Paulo. Os fungicidas foram aplicados mediante pulverizador costal pressurizado a CO2, e vazão de 250 L de calda por hectare. Adotou-se o delineamento de blocos casualizados, com 6 tratamentos e 4 repetições. Cada unidade amostral correspondeu a uma área de 22,5 m2. As variáveis avaliadas foram severidade de sintomas das cercosporioses, número de cicatrizes foliares, massa fresca das hastes, realizadas em DATA 20/03/2014, em Jaboticabal, e 23/04/2014, em Ibitinga, a avaliação de massa de grãos realizadas em DATA 30/03/2014, em Jaboticabal, e 30/05/2014, em Ibitinga. Os dados foram submetidos a análises multivariada de agrupamento por método hierárquico, processada com a distância euclidiana como medida de semelhança ... / The early and late leaf spot in peanut crop are responsible for an important economic damage. Represents by Cercospora arachidicola and Cercosporidium personatum, the early and late leaf spot can occasion production damages in the peanut crop between 50 – 70 %. Among the control measure, the use of contact and systemic fungicide are important. Currently, the sprays are previous established on a set 14 – 15 days schedule, beginning in the 20-30 days after the plants emerge. The previously established of fungicides application has generate a huge problems, related to the bad positioning and the use of fungicides, like in the wrong moment of application, or in the absence in fundamental moment to the control of the disease. It was evaluated the efficiency and a minimum number of fungicides applications in the control of early and late leaf spot in peanut crop. The fungicides evaluated were chlorothalonil, epoxiconazol + pyraclostrobin in the dosages of 4 ml and 2.4 ml/L, applied over 15 days, in field condition located in Jaboticabal and Ibitinga, state of São Paulo . Fungicides were applied using a CO2 pressurized backpack sprayer, and flow of 250 L of spray per hectare. It was adopted the randomized block design, with 6 treatments and 4 repetition. Each sample unit corresponded to an area of 22.5 m2. The variable evaluated were severity of early and late leaf spot symptoms, numbers of leaf scars, fresh weight of stem and grain weight, held on a date of 20/03/2014, in Jaboticabal, and 23/04/2014, in Ibitinga, the evaluation of grain mass held in date of 30/03/2014, in Jaboticabal, and 30/05/2014, in Ibitinga. Through of the data were used exploratory multivariate analyzes by hierarchical clustering method, processed with the Euclidean distance as a measure of similarity between samples, and Ward as the method of connection groups. It was concluded that there is need for at least five applications ...

Orientador: Antonio de Goes / Banca: Rita de Cassia Panizzi / Banca: Eduardo José de Almeida / Resumo: As cercosporioses na cultura do amendoim são responsáveis por importante dano econômico. Representadas pela mancha castanha causada por Cercospora arachidicola e a mancha preta causada por Cercosporidium personatum, as cercosporioses podem acarretar perdas de produção na cultura do amendoim entre 50 a 70%. Dentre as medidas de controle destacam-se o uso de fungicidas de contato e sistêmicos. Atualmente são empregadas pulverizações pré-estabelecidas, espaçadas entre 14 -15 dias, iniciando-se a partir dos 20-30 dias após a emergência das plantas. O pré-estabelecimento das aplicações tem gerado inúmeros problemas, relacionados ao mal posicionamento e uso dos fungicidas, como aplicações em momentos inadequados, ou ausência em momentos fundamentais para o controle das doenças. Nesse estudo foi avaliado a eficiência e número mínimo de aplicações de fungicidas no controle das cercosporioses da cultura do amendoim. Para tal, foram avaliados os fungicidas clorotalonil, epoxiconazol + piraclostrobina nas dosagens 4 mL e 2,4 mL/L, aplicados em intervalos de 15 dias, em condições de campo, em plantios localizados em Jaboticabal e Ibitinga, estado de São Paulo. Os fungicidas foram aplicados mediante pulverizador costal pressurizado a CO2, e vazão de 250 L de calda por hectare. Adotou-se o delineamento de blocos casualizados, com 6 tratamentos e 4 repetições. Cada unidade amostral correspondeu a uma área de 22,5 m2. As variáveis avaliadas foram severidade de sintomas das cercosporioses, número de cicatrizes foliares, massa fresca das hastes, realizadas em DATA 20/03/2014, em Jaboticabal, e 23/04/2014, em Ibitinga, a avaliação de massa de grãos realizadas em DATA 30/03/2014, em Jaboticabal, e 30/05/2014, em Ibitinga. Os dados foram submetidos a análises multivariada de agrupamento por método hierárquico, processada com a distância euclidiana como medida de semelhança ... / Abstract: The early and late leaf spot in peanut crop are responsible for an important economic damage. Represents by Cercospora arachidicola and Cercosporidium personatum, the early and late leaf spot can occasion production damages in the peanut crop between 50 - 70 %. Among the control measure, the use of contact and systemic fungicide are important. Currently, the sprays are previous established on a set 14 - 15 days schedule, beginning in the 20-30 days after the plants emerge. The previously established of fungicides application has generate a huge problems, related to the bad positioning and the use of fungicides, like in the wrong moment of application, or in the absence in fundamental moment to the control of the disease. It was evaluated the efficiency and a minimum number of fungicides applications in the control of early and late leaf spot in peanut crop. The fungicides evaluated were chlorothalonil, epoxiconazol + pyraclostrobin in the dosages of 4 ml and 2.4 ml/L, applied over 15 days, in field condition located in Jaboticabal and Ibitinga, state of São Paulo . Fungicides were applied using a CO2 pressurized backpack sprayer, and flow of 250 L of spray per hectare. It was adopted the randomized block design, with 6 treatments and 4 repetition. Each sample unit corresponded to an area of 22.5 m2. The variable evaluated were severity of early and late leaf spot symptoms, numbers of leaf scars, fresh weight of stem and grain weight, held on a date of 20/03/2014, in Jaboticabal, and 23/04/2014, in Ibitinga, the evaluation of grain mass held in date of 30/03/2014, in Jaboticabal, and 30/05/2014, in Ibitinga. Through of the data were used exploratory multivariate analyzes by hierarchical clustering method, processed with the Euclidean distance as a measure of similarity between samples, and Ward as the method of connection groups. It was concluded that there is need for at least five applications ... / Mestre

No description available.

Zugl.: Göttingen, Univ., Diss., 2007

Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references (p.48-50).

Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2017-04-24T12:56:09Z No. of bitstreams: 1 texto completo.pdf: 470215 bytes, checksum: 438e4bc46be6403987d8bb5504b17040 (MD5) / Made available in DSpace on 2017-04-24T12:56:09Z (GMT). No. of bitstreams: 1 texto completo.pdf: 470215 bytes, checksum: 438e4bc46be6403987d8bb5504b17040 (MD5) Previous issue date: 2003-03-07 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / A mancha de olho pardo do cafeeiro, cujo agente etiológico é Cercospora coffeicola, é uma das mais antigas e importantes doenças da América Latina. Como a disponibilidade de conídios do patógeno é requerimento básico para vários estudos, é necessário que o fungo esporule abundantemente in vitro. As informações sobre a capacidade de esporulação de Cercospora spp., especificamente C. coffeicola, em meio de cultura, são escassas e contraditórias. Neste trabalho estudaram-se os efeitos de regimes de luz, meios de cultura, pH do meio de cultura e adição de vitaminas na esporulação de C. coffeicola, bem como compararam-se isolados do patógeno quanto à capacidade de esporulação. Adicionalmente, estudou-se a germinação dos conídios do fungo produzidos sob as condições mais propícias à esporulação. Compararam-se cinco meios de cultura, sob três regimes de luz. Os meios V8 (3,55 x 10 3 conídios/cm 2 ) e extrato de pó de café (EPC)+V8 (4,53 x 10 2 conídios/cm 2 ) sob o regime de luz contínua propiciaram melhor esporulação. Os isolados CC-01(4,20 x 10 4 conídios/cm 2 ) e RAP-02 (2,45 x 10 5 conídios/cm 2 ), nos meios V8 e EPC+V8 sob luz contínua, foram os que apresentaram maior capacidade de esporulação. A faixa de pH entre 4,0 e 6,0 não afetou a esporulação dos isolados CC-01 (9,70 x 10 4 conídios/cm 2 ) e RAP-02 (4,56 x 10 4 conídios/cm 2 ), cultivados nos meios V8 e EPC+V8 sob luz contínua. A adição de biotina (50 μg/L), tiamina (100 μg/L) ou Panvit ® (uma drágea/L) aos meios V8 e EPC+V8, não influenciou na esporulação dos isolados CC-01 e RAP-02. A germinação dos conídios em ágar-água 2% foi alta (média geral 97%), independente do isolado (CC-01 ou RAP-02), meio de cultura (V8 ou EPC+V8) ou da fonte de vitamina (tiamina ou Panvit ® ) adicionada ao meio. / Brown eye spot, caused by Cercospora coffeicola, it is one of the oldest and most important diseases of coffee plants in Latin America. As the availability of pathogen spores is a requirement to many basic studies, it is necessary to have abundant sporulation of the pathogen in vitro. Information about the sporulation of Cercospora spp., specifically C. coffeicola, in culture media is scarce and contradictory. Therefore this work aimed to study the effect of light regimes, culture media, pH of culture media, and addition of vitamins on sporulation of C. coffeicola. Additionally, sporulation of pathogen isolates was compared and spore germination of the pathogen produced under the most favorable sporulation conditions was studied. Five culture media and three light exposure regimes were compared. V8 (3.55 x 10 3 spores/cm 2 ) and extract of ground coffee (EPC)+V8 (4.53 x 10 2 spores/cm 2 ) media were the most efficient in inducing sporulation, under continuous light. In the two best media, under continuous light, five pathogen isolates were compared. The isolates CC-01 (4.20 x 10 4 spores/cm 2 ) and RAP-02 (2.45 x 10 5 spores/cm 2 ) produced highest number of conidia. In the V8 and EPC+V8 media isolates CC-01 (9.70 x 10 4 spores/cm 2 ) and RAP-02 (4.56 x 10 4 spores/cm 2 ) sporulated well, with no statistical difference, on the medium pH ranging from 4.0 to 6.0. The addition of the vitamins biotin (50 μg/L), thiamin (100 μg/L), or Panvit ® (a capsule/L) to the V8 and EPC+V8 media had no effect on sporulation of CC-01 (1.28 x 10 5 spores/cm 2 ) and RAP-02 (8.41 x 10 3 spores/cm 2 ) isolates. Conidia germination rates high (average 97%), regardless isolate (CC- 01 or RAP-02), culture medium (V8 or EPC+V8), or vitamin source (thiamin or Panvit ® ) added to the medium. / Dissertação importada do Alexandria

Forecasts for the first fungicide application to manage cercospora blight of carrot (Daucus carota L. subsp. sativus (Hoffim) Arcang) caused by Cercospora carotae (Passerini) Solheim were evaluated during the summers of 1991 and 1992. In the forecast based on infection, the blight severity values (BSV) were calculated for each day using duration of leaf wetness, relative humidity and temperature. The first fungicide was applied when the cumulative blight severity value reached 14 (CBSV 14) and 18 (CBSV 18). The forecasts were compared with the 50% disease incidence threshold method where the first fungicide was applied when the middle leaf of 50% of plants was diseased, and the conventional method where the first fungicide application was made when the plant height reached 15 cm. For the threshold of CBSV 14 and CBSV 18, no loss was observed in yield and fewer fungicides were applied as compared to conventional and 50% disease incidence threshold methods. Three years of weather data from experimental plots and 155 commercial field data were used to study the behaviour of CBSV at 50% disease incidence threshold. Only in 3% of the fields, the disease incidence of 50% was observed before the CBSV reached 11. The increase from CBSV 11 to 20 was rapid. Depending on environmental conditions the first fungicide at a CBSV range of 11 to 20 is proposed rather than a critical threshold since no loss in yield was observed at 18 in the experimental plots. No fungicide is applied until the CBSV reaches 11 and the application must not be delayed after CBSV reaches 20.