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  • About
  • 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.
1

Studies on the physiology of Colletotrichum circinans

Soley, Inga Nella. January 1937 (has links)
Thesis (M.A.)--University of Wisconsin--Madison, 1937. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf 22).
2

Untersuchungen zur Regulation und Bedeutung der Chitin-Synthese beim Maispathogen Colletotrichum graminicola (Ces.) Wils. (Teleomorph: Glomerella graminicola Politis) /

Werner, Stefan. January 2002 (has links) (PDF)
Halle, Wittenberg, Universiẗat, Diss., 2002.
3

Mass production of Colletotrichum coccodes

Yu, Xuefeng. January 1997 (has links)
No description available.
4

Mass production of Colletotrichum coccodes

Yu, Xuefeng. January 1997 (has links)
Colletotrichum coccodes is being developed as a bioherbicide to control velvetleaf. An effective and economic process for mass production of C. coccodes sports is required for its possible development as a bioherbicide. A modified Richard's solution containing V-8 juice has been used to produce C. coccodes spores in shake flasks. However, V-8 juice is not available as a bulk commodity and is too expensive for commercial production of a bioherbicide. Soy protein and casamino acids were equal to and can replace V-8 juice for sporulation of C. coccodes . Using the Plackett-Burman experimental design, the effect of the various components in a complex medium on both the sporulation and mycelial biomass of C. coccodes were determined. Carbon concentration and carbon to nitrogen ratio as well as their interaction are critical for C. coccodes growth and sporulation. In medium containing 10 g/l carbon with C:N ratios from 10:1 to 15:1, 8 x 107 C. coccodes spores per ml were produced. Germination of the spores was 90% and they caused extensive shoot dry weight reduction of inoculated velvetleaf. C:N ratios from 10:1 to 15:1 am optimal for C. coccodes sporulation. A cyclone column bioreactor was used to investigate the effects of environmental conditions on spore yield. C. coccodes sporulation was superior with low aeration (∼0.5vvm) and low pH (4.5--5.0) compared with high aeration (2 vvm) and high pH (6.5--7.5). The optimum temperature for sporulation was 24°C. C. coccodes sporulation commences when the dissolved oxygen supply becomes restricted. Spore yields of over 3.5 x 107 spores per ml can be obtained within four days from batch culture. Scale up to a 100 liter cyclone column bioreactor yielded 2.5 x 107 C. coccodes spores per ml within four days.
5

Spread of Colletotrichum coccodes from infected potato seed tubers and effect of fungicides on stem infection

Ingram, Jason Timothy, January 2008 (has links) (PDF)
Thesis (M.S. in plant pathology)--Washington State University, December 2008. / Title from PDF title page (viewed on Dec. 23, 2008). "Department of Plant Pathology." Includes bibliographical references.
6

The parasitism of Colletotrichum lindemuthianum (Sac. and Mag.) Bri. and Cav

Leach, J. G. January 1922 (has links)
Thesis (Ph. D.)--University of Minnesota, 1922. / Includes bibliographical references (leaves 53-56).
7

Isolierung des Proteinkinasegenes snf1 aus Colletotrichum graminicola und ihre Bedeutung für die Pathogenese

Wernitz, Marcus. January 2004 (has links) (PDF)
Konstanz, Universiẗat, Diss., 2004.
8

Caracterização e identificação de espécies de Colletotrichum associadas à antracnose do pimentão (Capsicum annuum) no Brasil / Characterization and identification of Colletotrichum species associated to anthracnose in pepper (Capsicum annuum) in Brazil

Tozze Junior, Hugo Jose 01 February 2008 (has links)
A antracnose é uma das doenças mais importantes do pimentão em vários países. Por muitos anos, somente C. gloeosporioides foi relatado como agente causal da antracnose desta cultura no Brasil. Entretanto, recentemente C. acutatum e C. capsici também tem sido associados a esta doença em algumas regiões do país. Neste trabalho, 56 isolados de Colletotrichum obtidos de pimentão e procedentes de diferentes regiões produtoras do país foram caracterizados e identificados por meio de algumas características morfológicas e culturais, e pela análise por PCR utilizando oligonucleotídeos espécie-específicos. Isolados representativos de cada espécie identificada na população amostrada também foram caracterizados quanto à patogenicidade em frutos de pimentão verdes e maduros, feridos e não feridos e quanto a sensibilidade aos fungicidas azoxistrobina, carbendazim, tiabendazol, tebuconazol, captana, clorotalonil e cloreto de benzalcônio. Os resultados demonstram que C. acutatum é a espécie predominante nas principais regiões produtoras de pimentão do país, representando cerca de 72% da população amostrada. C. capsici foi encontrada com freqüência aproximada de 14%, nos estados de São Paulo e Minas Gerais. C. gloeosporioides representou apenas 5% da população amostrada e teve distribuição restrita ao estado de São Paulo e ao Distrito Federal. Um único isolado de C. coccodes foi encontrado no Rio Grande do Sul. Além dessas espécies, isolados identificados como C. boninense foram encontrados em São Paulo e no Rio Grande do Sul, com freqüência de 7% na população amostrada. Este parece ser o primeiro relato de C. boninense infectando pimentão no Brasil e em outras partes do mundo. A caracterização patogênica mostrou que isolados representativos de todas as espécies foram patogênicos aos frutos maduros feridos e não feridos. Nos frutos verdes feridos, apenas os isolados de C. acutatum e de C. capsici promoveram sintomas. Não foram observados sintomas nos frutos verdes sem ferimentos durante o período de avaliação do experimento (12 dias) para nenhum dos isolados. C. acutatum demonstrou ser a espécie mais agressiva, apresentando os menores períodos de latência e a maior esporulação tanto em frutos verdes (feridos) como nos maduros (feridos e não feridos). Os isolados pertencentes a diferentes espécies de Colletotrichum apresentaram sensibilidade diferenciada para todos os fungicidas sistêmicos avaliados. Os isolados de C. acutatum foram mais sensíveis a azoxistrobina, enquanto os isolados de C. gloeosporioides demonstraram a menor sensibilidade para este fungicida. Os isolados de C. gloeosporioides e C. boninense foram os mais sensíveis aos benzimidazóis (carbendazim e tiabendazol), enquanto o isolado de C. coccodes teve a menor sensibilidade para estes fungicidas. O fungicida tebuconazol promoveu o maior controle sobre o crescimento micelial dos isolados. Para este fungicida, C. capsici demonstrou ser a espécie menos sensível. Os resultados deste trabalho demonstram a presença de pelo menos cinco espécies de Colletotrichum responsáveis pela antracnose do pimentão no país e evidenciam a presença de importantes diferenças entre essas, que devem ser consideradas durante o manejo da doença. / In several countries, anthracnose is one of the most serious diseases in pepper. C. gloeosporioides has, for many years, been reported as the causal agent of anthracnose in Brazil. C. acutatum and C. capsici have only recently been reported as agents of anthracnose in some regions of the country. In this study, 56 isolates of Colletotrichum obtained from pepper from different areas of the country were characterized and identified based on the morphological characteristics of the conidia, as well as culture characteristics and PCR analysis with species-specific pairs of primers. Isolates representative of each identified species in the sampled population were also characterized according to their pathogenicity in pepper fruits (unripe, ripe, wounded and nonwounded) and also according to their sensitivity to fungicide (azoxystrobin, carbendazim, thiabendazole, tebuconazole, captan, chlorothalonil and benzalkonium chloride). The results have showed that C. acutatum is the most prevalent species found in the main production areas of pepper, present in about 72% of the sampled population. C. capsici was equivalent to 14% of the sampled population and found in the states of São Paulo and Minas Gerais. C. gloeosporioides was present in only 5% of the samples and it was restricted to the state of São Paulo and Distrito Federal. Only one isolate of C. coccodes was found in Rio Grande do Sul. Besides theses species, isolates of C. boninense were found in São Paulo and Rio Grande do Sul, with an occurrence of 7% in the sampled population. This seems to be the first report of C. boninense infecting pepper in Brazil and other parts of the world. The pathogenic characterization showed that representative isolates of all species were pathogenic in ripe, wounded, or nonwounded fruits. In wounded green fruit, only isolates of C. acutatum and C. capsici caused infection resulting in disease symptoms. No disease symptoms were observed in green nonwounded fruits inoculated with all Colletotrichum isolates, after 12 days of inoculation. C. acutatum was the most aggressive species with the shortest periods of latency and the highest rate of sporulation in either green wounded fruits or ripe fruits (wounded and nonwounded). Isolates of different species of Colletotrichum showed different sensitivity to the systemic fungicides evaluated. The isolates of C. acutatum were more sensitive to azoxystrobin, whereas C. gloeosporioides showed the lowest sensitivity to this fungicide. C. gloeosporioides and C. boninense isolates were the most sensitive to benzimidazoles fungicides (carbendazim and thiabendazole), whereas C. coccodes isolates showed the lowest sensitivity to these fungicides. The tebuconazol fungicide exerted the highest effect on mycelial growth for all Colletotrichum species. C. capsici showed to be less sensitive to this fungicide. The results of this work have shown the presence of at least five species of Colletotrichum responsible for anthracnose in pepper in Brazil and have made evident the importance of the differences between these species, which must be taken into account for the control of the disease.
9

Caracterização e identificação de espécies de Colletotrichum associadas à antracnose do pimentão (Capsicum annuum) no Brasil / Characterization and identification of Colletotrichum species associated to anthracnose in pepper (Capsicum annuum) in Brazil

Hugo Jose Tozze Junior 01 February 2008 (has links)
A antracnose é uma das doenças mais importantes do pimentão em vários países. Por muitos anos, somente C. gloeosporioides foi relatado como agente causal da antracnose desta cultura no Brasil. Entretanto, recentemente C. acutatum e C. capsici também tem sido associados a esta doença em algumas regiões do país. Neste trabalho, 56 isolados de Colletotrichum obtidos de pimentão e procedentes de diferentes regiões produtoras do país foram caracterizados e identificados por meio de algumas características morfológicas e culturais, e pela análise por PCR utilizando oligonucleotídeos espécie-específicos. Isolados representativos de cada espécie identificada na população amostrada também foram caracterizados quanto à patogenicidade em frutos de pimentão verdes e maduros, feridos e não feridos e quanto a sensibilidade aos fungicidas azoxistrobina, carbendazim, tiabendazol, tebuconazol, captana, clorotalonil e cloreto de benzalcônio. Os resultados demonstram que C. acutatum é a espécie predominante nas principais regiões produtoras de pimentão do país, representando cerca de 72% da população amostrada. C. capsici foi encontrada com freqüência aproximada de 14%, nos estados de São Paulo e Minas Gerais. C. gloeosporioides representou apenas 5% da população amostrada e teve distribuição restrita ao estado de São Paulo e ao Distrito Federal. Um único isolado de C. coccodes foi encontrado no Rio Grande do Sul. Além dessas espécies, isolados identificados como C. boninense foram encontrados em São Paulo e no Rio Grande do Sul, com freqüência de 7% na população amostrada. Este parece ser o primeiro relato de C. boninense infectando pimentão no Brasil e em outras partes do mundo. A caracterização patogênica mostrou que isolados representativos de todas as espécies foram patogênicos aos frutos maduros feridos e não feridos. Nos frutos verdes feridos, apenas os isolados de C. acutatum e de C. capsici promoveram sintomas. Não foram observados sintomas nos frutos verdes sem ferimentos durante o período de avaliação do experimento (12 dias) para nenhum dos isolados. C. acutatum demonstrou ser a espécie mais agressiva, apresentando os menores períodos de latência e a maior esporulação tanto em frutos verdes (feridos) como nos maduros (feridos e não feridos). Os isolados pertencentes a diferentes espécies de Colletotrichum apresentaram sensibilidade diferenciada para todos os fungicidas sistêmicos avaliados. Os isolados de C. acutatum foram mais sensíveis a azoxistrobina, enquanto os isolados de C. gloeosporioides demonstraram a menor sensibilidade para este fungicida. Os isolados de C. gloeosporioides e C. boninense foram os mais sensíveis aos benzimidazóis (carbendazim e tiabendazol), enquanto o isolado de C. coccodes teve a menor sensibilidade para estes fungicidas. O fungicida tebuconazol promoveu o maior controle sobre o crescimento micelial dos isolados. Para este fungicida, C. capsici demonstrou ser a espécie menos sensível. Os resultados deste trabalho demonstram a presença de pelo menos cinco espécies de Colletotrichum responsáveis pela antracnose do pimentão no país e evidenciam a presença de importantes diferenças entre essas, que devem ser consideradas durante o manejo da doença. / In several countries, anthracnose is one of the most serious diseases in pepper. C. gloeosporioides has, for many years, been reported as the causal agent of anthracnose in Brazil. C. acutatum and C. capsici have only recently been reported as agents of anthracnose in some regions of the country. In this study, 56 isolates of Colletotrichum obtained from pepper from different areas of the country were characterized and identified based on the morphological characteristics of the conidia, as well as culture characteristics and PCR analysis with species-specific pairs of primers. Isolates representative of each identified species in the sampled population were also characterized according to their pathogenicity in pepper fruits (unripe, ripe, wounded and nonwounded) and also according to their sensitivity to fungicide (azoxystrobin, carbendazim, thiabendazole, tebuconazole, captan, chlorothalonil and benzalkonium chloride). The results have showed that C. acutatum is the most prevalent species found in the main production areas of pepper, present in about 72% of the sampled population. C. capsici was equivalent to 14% of the sampled population and found in the states of São Paulo and Minas Gerais. C. gloeosporioides was present in only 5% of the samples and it was restricted to the state of São Paulo and Distrito Federal. Only one isolate of C. coccodes was found in Rio Grande do Sul. Besides theses species, isolates of C. boninense were found in São Paulo and Rio Grande do Sul, with an occurrence of 7% in the sampled population. This seems to be the first report of C. boninense infecting pepper in Brazil and other parts of the world. The pathogenic characterization showed that representative isolates of all species were pathogenic in ripe, wounded, or nonwounded fruits. In wounded green fruit, only isolates of C. acutatum and C. capsici caused infection resulting in disease symptoms. No disease symptoms were observed in green nonwounded fruits inoculated with all Colletotrichum isolates, after 12 days of inoculation. C. acutatum was the most aggressive species with the shortest periods of latency and the highest rate of sporulation in either green wounded fruits or ripe fruits (wounded and nonwounded). Isolates of different species of Colletotrichum showed different sensitivity to the systemic fungicides evaluated. The isolates of C. acutatum were more sensitive to azoxystrobin, whereas C. gloeosporioides showed the lowest sensitivity to this fungicide. C. gloeosporioides and C. boninense isolates were the most sensitive to benzimidazoles fungicides (carbendazim and thiabendazole), whereas C. coccodes isolates showed the lowest sensitivity to these fungicides. The tebuconazol fungicide exerted the highest effect on mycelial growth for all Colletotrichum species. C. capsici showed to be less sensitive to this fungicide. The results of this work have shown the presence of at least five species of Colletotrichum responsible for anthracnose in pepper in Brazil and have made evident the importance of the differences between these species, which must be taken into account for the control of the disease.
10

Caracterização e controle de colletotrichum spp. em seringueira (Hevea brasiliensis)

Sierra Hayer, Juan Fernan [UNESP] 05 February 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-05Bitstream added on 2014-06-13T20:37:50Z : No. of bitstreams: 1 sierrahayer_jf_me_botfca.pdf: 13042883 bytes, checksum: c8c75feb8bc74ce204bc7a174adc9e95 (MD5) / A cultura da seringueira [Hevea brasiliensis (Willd. ex Adr. Jussieu) Muell. Arg.] vem sendo atacada por várias doenças de importância econômica, dentre as quais está a antracnose, causada pelo fungo Colletotrichum sp. (teleomorfo: Glomerella sp.). Este fungo causa vários danos na planta como lesões nos folíolos, nos ponteiros, nos ramos, nos frutos e cancros no painel de sangria. Somente Colletotrichum gloeosporioides foi relatado como agente causal desta doença no Brasil. O presente trabalho teve como objetivo identificar isolados de Colletotrichum spp. de seringueira de diversas regiões de plantio do Estado de São Paulo. O trabalho foi conduzido em cinco fases: a) caracterização cultural, na qual foram observadas a coloração e o aspecto das culturas in vitro. Produção de conídios e taxa de crescimento em seis temperaturas (10, 15, 20, 25, 30 e 35 °C); b) caracterização morfológica, na qual foi medido comprimento, largura e observado o formato dos conídios; c) teste de patogenicidade em folíolos destacados e em discos de folíolos, com quatro isolados de seringueira e dois de citros; d) crescimento em benomyl em quatro concentrações de princípio ativo; e) Identificação molecular para culturas monospóricas e multispóricas com primers específicos para as espécies de Colletotrichum gloeosporioides e Colletotrichum acutatum e os primers ITS1 e ITS4 os quais amplificaram uma pequena região (18S) e uma grande região (28S), e estes também permitiram a amplificação da região 5.8S do rDNA e os espaçadores internos transcritos (ITS1 e ITS2), e f) testes de crescimento em meio de cultivo acrescido com fungicidas: flutriafol, tebuconazol, epoxiconazol + piradostrobina, clorotalonil + tiofonato-metílico, captana, mancozebe, carbendazim, azoxistrobina + ciproconazol e propiconazol. Neste teste foram utilizados quatro isolados de diferentes órgãos da planta... / The rubber cultivation [Hevea brasiliensis (Willd. ex Adr. Jussieu) Muell. Arg.] is being attacked by several diseases of economic importance, among which is the anthracnose; this is caused by the fungus Colletotrichum spp. (teleomorph: Glomerella spp). This fungus causes several damages in the plant such as injuries in the leaves, branches, fruits and cankers in the taping panel. Only Colletotrichum gloeosporioides was reported as the causal agent of this disease in Brazil. The aim of this study was to identify isolates of the fungus Colletotrichum spp. from rubber trees, localized in different regions of Sao Paulo state. The study was carried out by six phases: a) culture characterization, in which the color and the culture appearance were observed in vitro, conidial production and growth rate at six temperatures (10, 15, 20, 25, 30, 35 °C); b) morphological characterization, which consist of measuring the length and width, and observed the shape of the conidia; c) pathogenicity test on selected leaves and disks of leaves, with four isolates from rubber and two isolates from citrus; d) growth in fungicide benomyl at four concentrations of active ingredient; e) molecular identification for monosporic and multisporic cultures with specific primers to the species of Colletotrichum gloeosporioides and Colletotrichum acutatum and ITS1 and ITS4 primers which amplified a small region (18S) and a large region (28S), and these also allowed the amplification of 5.8S rDNA and internal transcribed spacers (ITS1 and ITS2); f) Growth tests in culture medium supplemented with fungicides: flutriafol, tebuconazole, epoxiconazole + piradostrobina, chlorothalonil + tiofonato-methyl, captan, mancozeb, carbendazim, azoxystrobin + cyproconazole and propiconazole. In this test, four isolates were used from... (Complete abstract click electronic access below)

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