Mancha de micosferela em Eucalyptus globulus: características e ascogênese do patógeno, estrutura e composição química foliar
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Data
2011-05-25
Autores
Passador, Martha Maria [UNESP]
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Editor
Universidade Estadual Paulista (Unesp)
Resumo
Muitas espécies de eucalipto são cultivadas no mundo todo e muitos patógenos evoluíram ou se adaptaram á cultura, principalmente fungos, desde a fase de viveiro até os plantios adultos. A mancha de micosferela é uma das principais doenças e o Eucalyptus globulus uma das espécies mais suscetíveis. O presente estudo foi iniciado a partir de isolamentos monospóricos de espécies fúngicas associadas à mancha de micosferela a partir de folhas e ramos de E. globulus provenientes de Bagé-RS, Pedras Altas-RS, Botucatu-SP, Jacareí-SP e Itapeva-SP, que possibilitou a obtenção de 46 isolados, que foram observados quanto à forma de germinação e crescimento micelial. A determinação das espécies deu-se por meio de PCR com primers da região genômica ITS1 e ITS4 e sequenciamento (vide capítulo 1). Como resultado, várias espécies foram encontradas e descritas. Mudas de E. globulus foram inoculadas pelo método da exposição de mudas sadias à folhas com sintomas de Teratosphaeria nubilosa, por ejeção de ascósporos, em casa de vegetação. Estas mudas foram avaliadas e folhas com os sintomas do fungo foram coletadas a partir da terceira semana até a décima terceira semana da inoculação. Para realização de cortes e estudos histológicos, que permitiram observar a formação dos pseudotécios desde o seu início três semanas após a inoculação, as hifas ascógenas dentro do pseudotécio após nove semanas e a formação das ascas e ascósporos após 11 e 13 semanas, respectivamente (vide capítulo 2). Através de estudos anatômicos, verificou-se que as folhas adultas apresentaram menor intensidade dos sintomas, o que pode estar relacionado com a compactação das células do parênquima, enquanto que as folhas jovens apresentam espaços intercelulares no parênquima lacunoso, no parênquima paliçádico e na câmara subestomática...
Many Eucalyptus species are grown worldwide, and many pathogens have evolved and adapted to the culture. The cultivation of eucalyptus is affected by a number of diseases. Many pathogens occur in several eucalypt species, especially fungi, from the nursery to the planting adults. The Mycosphaerella leaf disease is a major disease and Eucalyptus globulus one of the most susceptible species. This study consisted of spore isolates of fungal species associated with Mycosphaerella leaf disease from leaves and stems of E. globulus from Bage-RS, Pedras Altas-RS, Botucatu-SP, Jacareí-SP, Itapeva-SP, which allowed the collection of 46 isolatesm sequenced (see Chapter 1). As a result, several species were found and described. Seedlings of E.globulus were inoculated by exposure to leaves of healthy seedlings with symptoms of Teratosphaeria nubilosa, for ejection of ascospores in the greenhouse. Seedlings were evaluated, and leaves with the symptoms of the fungus were collected from the third week up to thirteenth week of inoculation. To carry out studies and histological sections, which allowed the formation of the pseudothecia from its beginning three weeks after inoculation, the formation of the ascogenous hyphae within pseudothecia after nine weeks, and the formation of asci and ascospores after 11 and 13 weeks, respectively (see Chapter 2). Through anatomical studies, it was found that if the adult leaves had a lower intensity of symptoms, which may be related to compression of the parenchyma cells, while the young leaves have intercellular spaces in the spongy parenchyma, palisade parenchyma and in substomatal chambers facilitating the formation of stroma (see Chapter 3). Essential oils of leaves and young adults, healthy and stain micosferela were extracted by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The data of chemical composition and the respective percentages... (Complete abstract click electronic access below)
Many Eucalyptus species are grown worldwide, and many pathogens have evolved and adapted to the culture. The cultivation of eucalyptus is affected by a number of diseases. Many pathogens occur in several eucalypt species, especially fungi, from the nursery to the planting adults. The Mycosphaerella leaf disease is a major disease and Eucalyptus globulus one of the most susceptible species. This study consisted of spore isolates of fungal species associated with Mycosphaerella leaf disease from leaves and stems of E. globulus from Bage-RS, Pedras Altas-RS, Botucatu-SP, Jacareí-SP, Itapeva-SP, which allowed the collection of 46 isolatesm sequenced (see Chapter 1). As a result, several species were found and described. Seedlings of E.globulus were inoculated by exposure to leaves of healthy seedlings with symptoms of Teratosphaeria nubilosa, for ejection of ascospores in the greenhouse. Seedlings were evaluated, and leaves with the symptoms of the fungus were collected from the third week up to thirteenth week of inoculation. To carry out studies and histological sections, which allowed the formation of the pseudothecia from its beginning three weeks after inoculation, the formation of the ascogenous hyphae within pseudothecia after nine weeks, and the formation of asci and ascospores after 11 and 13 weeks, respectively (see Chapter 2). Through anatomical studies, it was found that if the adult leaves had a lower intensity of symptoms, which may be related to compression of the parenchyma cells, while the young leaves have intercellular spaces in the spongy parenchyma, palisade parenchyma and in substomatal chambers facilitating the formation of stroma (see Chapter 3). Essential oils of leaves and young adults, healthy and stain micosferela were extracted by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The data of chemical composition and the respective percentages... (Complete abstract click electronic access below)
Descrição
Palavras-chave
Eucalipto, Mirtacea, Mancha de micosferela, Mycosphaerella leaf disease
Como citar
PASSADOR, Martha Maria. Mancha de micosferela em Eucalyptus globulus: características e ascogênese do patógeno, estrutura e composição química foliar. 2011. ix, 125 f. Tese (doutorado) - Universidade EStadual Paulista, Faculdade de Ciências Agronômicas, 2011.