Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Erva mate (Ilex paraguariensis A. St.-Hil.) is a species widely cultivated in southern Brazil and adjacent countries, whose leaves and fine branches, appropriately prepared, offer the mate-tea, the most popular tea consumed in Brazil and exported to all over the world. root-rot is the main disease of this species in Brazil and may attack plantules and seedlings in nurseries as well as adult trees in orchards. The disease is caused by Fusarium spp., besides Pythium sp. and Rhizoctonia sp. causing serious damages due to the root system destruction, it causes, in the most serious cases the death of the plant. The incidence and the severity of the disease might be influenced by the cultivation methods and management of the orchard, with the use of mineral fertilizers without any technical criteria or the absence of fertilization, soil liming and orchards cultivation under the sun. In order to verify such hypothesis, 25 rural estates were marked in different counties of Vale do Taquari area in the state of Rio Grande do Sul BR. These areas had some orchards with symptoms of the disease and others in healthy conditions. Information about the crop and management characteristics, as well as soil for chemical and biological analysis, were collected and correlated through Pearson and outspread in direct and indirect effects through Path Analysis. In the nurseries, the disease incidence might be correlated to the contamination of the seed and the transmitted pathogens besides causing the death of the seedling may also have been transmitted to health seedlings, and they might had been transported to the field, contaminated areas which were previously free from the pathogen. Some practices applied by the farmers may cause the increase in the incidence of pathogens in the seeds and seedlings. In order to verify such hypothesis, some nurseries have been selected in the area of Vale do Taquari RS, where some samples of seeds, plantules, seedlings and substrata were collected in order to analyze the inoculation potential of the pathogens in each sort of sample. From the analysis of the substrata, seeds, seedlings different fungi colonies of the genre Fusarium were isolated, purified and stored for pathogenicity tests and, Trichoderma, for isolated selection with potential Fusarium antagonist. Moreover, experiments were installed in 2 nurseries, aiming at testing the benefits of commercial chemical (Captan SC®) and biological (Agrotrich® e Trichodel®) products, in the seed treatment, aiming at controlling the incidence of the disease on the seedbed. In the orchards, among the studied variables, it was noticed that the organic matter is the most influential over the Fusarium population in the soil and a linear positive correlation was obtained. Besides this variable, the calcium and phosphorus contends also have some sort of influence over the Fusarium population, however, in a less significant way. In the nurseries, the high percentage of seeds contaminated by Fusarium and Rhizoctonia was noticed. It was also noticed that the contamination begins in the flower and fruit phase. It was also observed that the technique of seed processing and stratification applied by the farmers, contribute to the increase in the incidence of pathogens. Besides the seeds, it was also noticed that the plantules and seedlings at the end of the nursery cycle, present pathogen contamination in their roots, although they did not present root-rot symptoms. The products Captan SC®, Agrotrich® and Trichodel® applied on the seed treatment, before the sowing, were not efficient in the Fusarium and Rhizoctonia control. In the Trichoderma spp. selection as potential antagonist to Fusarium, it was observed that SP-SFE-T1 isolated present high antagonic potential in in vitro tests. / A erva-mate (Ilex paraguariensis A. St.-Hil.) é uma espécie amplamente cultivada no sul do Brasil e países vizinhos, cujas folhas e galhos finos, preparados segundo método apropriado, fornecem o mate ou chimarrão, o mais popular chá consumido no Brasil e exportado para todo o mundo. A podridão-de-raízes é a principal doença da espécie no Brasil, podendo atacar plântulas e mudas no viveiro, bem como, árvores adultas em ervais. A doença é causada por Fusarium spp., além de Pythium sp. e Rhizoctonia sp. e provoca sérios danos decorrentes da destruição do sistema radicular, ocasionando, nos casos mais graves, morte da planta. Suspeita-se que a incidência e a severidade da doença são influenciadas pelos métodos de cultivo e por práticas de manejo do erval, como aplicação de adubos minerais sem critérios técnicos ou ausência de adubação, calagem do solo e cultivo de ervais a pleno sol. Para verificar tal hipótese, foram demarcadas 25 propriedades rurais, em diferentes municípios da região do Vale do Taquari-RS, as quais possuíam ervais com sintomas da doença, e outras com ervais sadios. Nesses ervais, foram coletadas informações a respeito das características de cultivo e manejo, assim como, solo para análise química e biológica. Estas informações foram correlacionadas entre si através da correlação de Pearson e desdobradas em efeitos diretos e indiretos através da Análise de Trilha. Nos viveiros, suspeita-se que a incidência da doença está correlacionada à contaminação das sementes utilizadas e que, patógenos transmitidos por sementes, além de causar mortalidade de mudas, podem ser transmitidos a mudas sadias e, estas, serem transportadas para o campo, contaminando áreas livres do patógeno. Além disso, algumas práticas utilizadas pelos viveiristas podem ocasionar aumento da incidência de patógenos nas sementes e mudas. Para verificar tal hipótese, foram demarcados viveiros na região do Vale do Taquari-RS, onde foram coletadas amostras de sementes, de plântulas, de mudas e de substrato para analisar o potencial de inóculo de patógenos presente em cada tipo de amostra. A partir das análises do substrato, das sementes e das mudas, diferentes colônias de fungos do gênero Fusarium foram isoladas, purificadas e armazenadas, para testes de patogenicidade e, Trichoderma, para seleção de isolados com potencial antagonista ao Fusarium. Além disso, foram instalados experimentos, em dois viveiros, a fim de testar a eficiência dos produtos comerciais, químico (Captan SC®) e biológico (Agrotrich® e Trichodel®), no tratamento de sementes, visando o controle da incidência da doença nas sementeiras. Nos ervais, entre as variáveis estudadas, verificou-se que a matéria orgânica é a que mais influencia na população de Fusarium do solo, obtendo-se uma correlação linear positiva. Além desta variável, os teores de cálcio e de fósforo no solo também exercem certa influencia na população de Fusarium, mas de forma menos significativa. Nos viveiros, constatou-se alta porcentagem de sementes contaminadas por Fusarium e Rhizoctonia e que, a contaminação começa já na fase de flores e frutos. Observou-se também, que a técnica de beneficiamento e estratificação das sementes, utilizada atualmente pelos viveiristas, contribui para o aumento da incidência de patógenos. Além das sementes, observou-se que plântulas e mudas no final do ciclo de viveiro, apresentam contaminação por patógenos nas suas raízes, mesmo que não apresentavam sintomas de podridão-de-raízes. Os produtos Captan SC®, Agrotrich® e Trichodel® utilizados no tratamento das sementes, previamente a semeadura, não foram eficientes no controle de Fusarium e Rhizoctonia. Na seleção de Trichoderma spp. com potencial antagonista ao Fusarium observou-se que o isolado SP-SFE-T1 apresentou alto potencial antagônico em testes in vitro .

Fungal diseases of trees are serious impediments to forest expansion and productivity. While the adverse effects of diseases of non-native plantation forest trees are increasingly recognized in Africa, the health of native trees has been virtually ignored. This is especially acute as many commercially propagated trees are related to native woody plants and recurrent movement of pathogens between native and non-native trees is increasingly being recorded. The genus Terminalia accommodates important indigenous tree species in Africa that provide a variety of valuable wood and non-wood products. Despite the importance of Terminalia spp., very little information has been recorded on their health problems. Research for this dissertation aimed at studying some of the fungal diseases of native and non-native Terminalia species in Africa. Special reference was provided to fungi in the Botryosphaeriaceae, a group of pathogens that infect host plants without always producing clear symptoms. A literature review, presented in Chapter One, highlighted the limited information available on the pathogens and pests associated with these trees. Most disease reports include minimal detail. Often the causal agents had been identified based only on morphology and were not classified to the species level. Studies performed in chapter two compared the assemblages of endophytic species of the Botryosphaeriaceae from T. catappa in Cameroon, South Africa and Madagascar. Five species were identified and two of these are new to science and provided with the names N. batangarum and L. mahajangana. The assemblage of the Botryosphaeriaceae varied from one country to another, however, colonization patterns in the three areas were similar. Greenhouse inoculation trials performed on young T. catappa trees showed variation among isolates tested, with L. pseudotheobromae being the most pathogenic. Chapter three represents the first investigation of the Botryosphaeriaceae on native Terminalia trees in Cameroon and Africa. Morphological and DNA sequence data were used to identify these species as L. theobromae, L. pseudotheobromae, L. parva and E. endophytica. Pathogenicity trials performed on young T. mantaly and T. catappa trees revealed that L. pseudotheobromae was the most virulent species. In chapter four, species of Botryosphaeriaceae on native Terminalia spp. in Southern Africa were studied. Nine species were identified from T. sericea and T. sambesiaca. Seven of these, L. crassispora, L. pseudotheobromae, D. alatafructa, P. olivaceum, N. parvum, N. kwambonambiense and N. vitifusiforme represented previously described species and two, L. cryptotheobromae and N. terminaliae, were described as new. The genetic analyses of populations of L. theobromae and L. pseudotheobromae presented in chapter five showed clear genetic divergence between L. theobromae and L. pseudotheobromae supporting their distinction as separate species. Both L. theobromae and L. pseudotheobromae populations possessed high gene diversity, moderate degrees of genotypic diversity, and high levels of gene flow between isolates from T. cacao and Terminalia spp. Both sexual and asexual modes of reproduction were found. The last chapter of this dissertation presents the description of a new genus in the Cryphonectriaceae, Aurifilum marmelostoma, using a combination of molecular and morphological tools. This fungus is the second genus in this family described from Terminalia spp. Pathogenicity tests conducted to assess its ability to cause disease revealed that the fungus is a possible pathogen of this tree. An extensive number of potentially pathogenic fungi, including five new species were found associated with native and non-native Terminalia spp. in Africa. As some of these fungal species could serve as sources of inoculum onto economically important crops, research presented in this dissertation provides a foundation for understanding health issues affecting Terminalia and related genera in selected regions in Africa. Hopefully, results of this study will serve as valuable tools in forestry management in Africa. Copyright / Thesis (PhD)--University of Pretoria, 2010. / Plant Production and Soil Science / Unrestricted

Made available in DSpace on 2014-06-12T23:01:24Z (GMT). No. of bitstreams: 2 arquivo8552_1.pdf: 533604 bytes, checksum: a260b9f76c8b82b2713fa5d4b3ad9d38 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2006 / A água doce é um recurso natural finito, cuja qualidade vem decaindo devido ao aumento da população e à deficiência de políticas públicas voltadas para a sua preservação. A rota de transmissão ambiental para protozoários e helmintos é particularmente significativa e envolve a água, o solo e o alimento. A partir da década de 1980, acrescentou-se a preocupação quanto à ocorrência de protozoários patogênicos tais como Cryptosporidium spp. e Giardia spp., em resposta ao crescente número de surtos envolvendo um grande número de pessoas, estando relacionados ao consumo de água e à ineficiência do tratamento aplicado na remoção de cistos e oocistos nas Estações de Tratamento de Água (ETA). No Brasil foi instituído a partir de 2003 o Sistema de Informação de Vigilância da Qualidade da Água de Consumo Humano (SISAGUA), instrumento de coleta de análises de dados a ser desenvolvido em âmbito nacional pelas áreas de vigilância ambiental em saúde, visando à garantia da qualidade da água distribuída à população. O presente estudo teve como objetivo detectar a presença de enteroparasitas, com ênfase em Cryptosporidium spp. em amostras de água consumida por parte da população do Distrito Sanitário VI, na cidade do Recife. As amostras foram coletadas em pontos considerados como início, meio e fim da rede de distribuição. A metodologia de sedimentação espontânea foi utilizada para pesquisa de enteroparasitas e outros organismos. Para a detecção de Cryptosporidium spp., utilizouse o método de concentração de oocistos através de membrana filtrante, seguido da identificação e contagem de estruturas álcool-ácido resistentes através da coloração histoquímica de Kinyoun. Como ensaios confirmatórios para Cryptosporidium spp., foram utilizadas as metodologias de Ensaio Imunoenzimático e Imunofluorescência Direta. Os parâmetros físico-químicos e microbiológicos foram avaliados de acordo com os padrões da Portaria nº 518/04/MS. Em 95,56% (86/90) das amostras de água, analisadas neste estudo foram encontrados organismos como: oocistos Cryptosporidium spp. (15,55%), cistos de Giardia spp. (3,85%), além de ovos de helmintos (47,78%), larvas de nematóides (28,78%) e organismos do zooplâncton (84,44%). Conclui-se que existe vulnerabilidade nos processos de tratamento da água para consumo humano, principalmente na etapa da filtração, que deveria ser eficiente na remoção física de partículas, com especial atenção aos organismos patogênicos e que a qualidade da água está comprometida desde a saída da ETA até o ponto de consumo. Torna-se necessário intensificar a vigilância em saúde ambiental relacionada à qualidade da água para consumo humano, garantindo que a água não ofereça riscos a saúde da população

A incorporação de substâncias antimicrobianas, entre elas os óleos essenciais, em embalagens tem como objetivo minimizar a contaminação microbiana em alimentos. No entanto, essa utilização é limitada por critérios sensoriais, sendo necessário determinar a concentração mínima necessária para inibir o desenvolvimento de micro-organismos sem afetar sensorialmente as características do alimento. Assim, os objetivos dessa pesquisa foram: determinar a concentração inibitória mínima (CIM) de óleos essenciais (OE) para Listeria monocytogenes (LM); avaliar do efeito da combinação de óleos essenciais para a redução da população de LM; avaliar a combinação de compostos ativos presentes em óleos essenciais para a inibição de LM, Pseudomonas spp e Salmonella spp; avaliar in vitro e in situ a eficiência antimicrobiana do filme à base de alginato incorporado de compostos ativos presentes em óleos essenciais; determinar a disponibilidade dos compostos ativos incorporados ao filme pela determinação dos compostos fenólicos totais; caracterizar o filme frente às propriedades mecânicas e propriedades de barreira, e verificar a aceitação pelo consumidor, através da análise sensorial, de fatias de salame embaladas com o filme antimicrobiano. Constatou-se que a combinação de eugenol (0,01%) e limoneno (0,04%) apresentou um maior efeito para a redução da população de LM comparado ao uso individual desses compostos, confirmando, portanto, a existência de sinergismo entre esses dois compostos. Em relação à Pseudomonas spp, o sinergismo foi constatado quando as concentrações de eugenol (0,15%) e de limoneno (0,30%) foram utilizadas, no entanto, para Salmonella spp o mesmo efeito não foi observado. Em ensaios in vitro apesar do aumento na concentração de eugenol e limoneno incorporados à matriz do filme, não houve diferença significativa para os valores de zona de inibição antimicrobiana porém, em ensaios in situ, a utilização desse filme como embalagem primária promoveu a redução de 2 log UFC/g da população de LM até o 10º dia de análise permanecendo constante até o 30º dia o que não ocorreu com a combinação de eugenol (0,15%) e limoneno (0,3%). A quantificação dos compostos fenólicos totais nas amostras mostrou que há correlação entre o teor de compostos fenólicos extraídos da amostra do filme e o comportamento de LM. As propriedades mecânicas e de barreira do filme à base de alginato não foram significativamente afetadas pelas concentrações de eugenol e limoneno avaliadas neste estudo. O sabor, o aroma e a aparência das amostras de salame foram aceitos pelos provadores mostrando que o uso do filme à base de alginato incorporado com eugenol e limoneno é viável para a aplicação como embalagem antimicrobiana para o controle de L. monocytogenes em salame fatiado. Este resultado é considerado importante, pois em alimentos com atividade de água e valores de pH adequados à multiplicação desse patógeno e armazenados sob refrigeração, a temperatura é capaz de selecionar a microbiota presente no alimento, favorecendo a multiplicação de micro-organismos psicrotróficos, como L. monocytogenes. / The incorporation of antimicrobial substances in packages aims at reducing food microbial contamination among which the phenolic compounds extract from plants have received special attention being natural and attending consumer demand. However, the use of these compounds is limited by sensory criteria and it is necessary to determine the minimum concentration required to inhibit the growth of microorganisms without affecting the sensory characteristics of the food. The aim of this research were: to determine the minimum inhibitory concentration (MIC) of essential oils (EO) for Listeria monocytogenes (LM); to evaluate effect of the combination of essential oils in order to reduce LM population; to evaluate the active compounds combination for the inhibition of LM, Pseudomonas spp, and Salmonella spp; to evaluate the antimicrobial efficiency in vitro and in situ of the alginate film incorporated with the active compounds; to determine the availability of the active compounds incorporated into the film for the determination of total phenolic compounds; to characterize the mechanical and barrier properties of the film, and to verify consumer acceptance of slices of salami packaged with the antimicrobial film. The combination of eugenol (0.01%) and limonene (0.04%) showed a greater effect for reducing LM population compared to the individual use of these compounds, confirming the existence of synergism between these two compounds. Regarding Pseudomonas spp, synergism was observed when the concentrations of eugenol (0.15%) and limonene (0.30%) were used, however, the same effect was not observed for Salmonella spp. In in vitro tests, despite of the increase in the concentration of limonene and eugenol incorporated in the film matrix, no significant difference for the antimicrobial inhibition zone values was observed. In in situ tests, the film containing eugenol (0.3%) and limonene (0.6%) promoted the reduction of 2 log CFU/g of LM population in sliced salami, while the combination of eugenol (0.15%) and limonene (0.3%) did not have the same effect. The quantification of the phenolic compounds in the film samples showed that there is correlation between the content of phenolic compounds extracted from the film sample and LM behavior. The mechanical properties of the barrier film and the alginate were not significantly affected by eugenol, and limonene concentrations evaluated in this study. The taste, flavor and appearance of the salami samples were accepted by the panel showing that the use of the alginate-based film incorporated with limonene and eugenol are feasible for use as antimicrobial packaging for the control of L. monocytogenes in sliced salami. This is an important result, because in food matrix with water activity and pH suitable for the pathogen growth, the storage under refrigerated condition is able to select the psycrothophic microorganisms, such as L. monocytogenes.

A intensidade de pastejo e o uso de fertilizantes nitrogenados podem impactar as características estruturais no dossel forrageiro afetando o ambiente luminoso dentro da vegetação, o que por sua vez pode influenciar a taxa fotossintética das folhas e do dossel, e também a produção de forragem. O objetivo deste trabalho foi descrever e explicar os efeitos da altura do dossel mantida constante e da taxa de crescimento aplicada como dose de nitrogênio (N) do capim Mulato II (Brachiaria brizantha × B. decumbens × B. ruziziensis) sob lotação contínua e taxa de lotação variável sobre as características produtivas e morfofisiológicas e a participação de diferentes categorias de folhas na composição do índice de área foliar (IAF) e na fotossíntese do dossel. O estudo foi conduzido na ESALQ/USP em Piracicaba-SP durante dois verões agrostológicos. O delineamento experimental foi o de blocos completos casualizados, com arranjo fatorial combinando três alturas do dossel (10, 25 e 40 cm) e duas taxas de crescimento geradas por doses de N (50 e 250 kg ha-1 ano-1), em três repetições. As variáveis estudadas incluíram: acúmulo total anual de forragem (ATF), IAF, interceptação de luz (IL), taxas de fotossíntese foliar e do dossel e contribuição relativa de diferentes categorias de folhas no IAF e na fotossíntese do dossel. O ATF aumentou linearmente com a altura do dossel (de 8560 para 13600 kg MS ha-1 ano-1). Aumentos também foram observados para IAF, IL, taxa de fotossíntese do dossel e contribuição das folhas maduras (MAD) no IAF e das folhas mais jovens completamente expandidas (JCE) na fotossíntese do dossel. A contribuição das folhas em expansão (EXP) e das folhas JCE no IAF, a taxa de fotossíntese das folhas EXP e MAD e a contribuição relativa das folhas EXP na fotossíntese do dossel aumentaram com a diminuição da altura do dossel. A aplicação de 250 kg N ha-1 ano-1 resultou em aumento de 137% no ATF em relação à taxa de 50 kg ha-1 ano-1. A maior dose de N resultou em aumento significativo no IAF, IL, taxa de fotossíntese de todas as categorias de folhas, fotossíntese do dossel e contribuição das folhas JCE na fotossíntese do dossel, embora a contribuição das folhas EXP na fotossíntese do dossel tenha sido maior na menor dose de N. A contribuição das folhas MAD na fotossíntese do dossel foi maior quando o dossel foi mantido mais alto e também com maior dose de N na altura de 10 cm. Nos dosséis de 25 cm a proporção de folhas MAD foi maior na menor dose de N e não diferiu entre doses de N quando mantido a 40 cm. Embora dosséis mantidos mais baixos apresentem maior proporção de folhas mais jovens (EXP e JCE) que são as que apresentam maiores taxas fotossintéticas, a fotossíntese do dossel e o ATF foram maiores nos dosséis mais altos. A aplicação de 250 kg N ha-1 ano-1 resulta em aumento na fotossíntese do dossel como consequência do aumento do IAF e da taxa de fotossíntese foliar, resultando em aumento no ATF. / Grazing intensity and nitrogen fertilization can impact the structural characteristics of the canopy affecting the light environment within the vegetation, which in turn may affect leaf and canopy photosynthetic rates, and also forage production. The objective of this study was to describe and explain the effects of canopy height kept constant and growth rate applied as N rate of Mulato II brachiariagrass (Brachiaria brizantha × B. decumbens × B. ruziziensis) under continuous stocking and variable stocking rate, on the productive and morpho-physiological characteristics, and the relative contribution of different leaf categories to the leaf area index (LAI) and to canopy photosynthesis. A field trial was conducted at ESALQ/USP in Piracicaba, SP, Brazil, during two summer growing seasons. A randomized complete block design was used, with a factorial arrangement combining three canopy heights (10, 25, and 40 cm) and two growth rates imposed by N rates (50 and 250 kg ha-1 yr-1), with three replications. The variables studied included: total annual forage accumulation (TFA), LAI, light interception (LI), leaf and canopy photosynthetic rates, and the relative contribution of different leaf categories to the LAI and to canopy photosynthesis. There was a linear increase in TFA with increased canopy height (from 8560 to 13600 kg DM ha-1 yr-1). The LAI, LI, canopy photosynthesis rates, the relative contribution of mature leaves (MAT) to the LAI, and relative contribution of the youngest fully-expanded leaves (YFE) to canopy photosynthesis also increased with canopy height. The relative contribution of expanding leaves (EXP) and YFE to the LAI, leaf photosynthesis of EXP and MAD leaves, and relative contribution of EXP leaves to canopy photosynthesis increased with the reduction in canopy height. The use of a greater N rate (250 kg N ha-1 yr-1) increased ATF by 137%. The application of more N (250 kg N ha-1 yr-1) also increased LAI, LI, photosynthetic rates of all leaf categories, canopy photosynthesis, and relative contribution of YFE leaves to canopy photosynthesis, but the relative contribution of EXP leaves to canopy photosynthesis was greater in the lesser N rate (50 kg N ha-1 yr-1). The relative contribution of MAT leaves to canopy photosynthesis was greater in taller canopies, and also in canopies maintained at 10 cm fertilized with 250 kg N ha-1 yr-1. The canopies maintained at 25 cm showed greater proportion of MAD leaves in the lesser N rate, and was similar in 40-cm canopies for both N rates. Although canopies kept at 10 cm showed greater relative proportion of younger leaves (EXP and YFE), which are those with greater photosynthetic rates, canopy photosynthesis and the TFA were greater in taller canopies. The application of 250 kg N ha-1 yr-1 results in increased canopy photosynthesis, due to increased LAI and leaf photosynthetic rate, resulting in increased TFA.

Bien moins médiatisées que la déforestation ou le changement climatique, les invasions biologiques n’en demeurent pas moins problématiques pour la conservation de nombreux écosystèmes ou le bon déroulement de nombreuses activités socio-économiques.Comprendre la façon dont les espèces exotiques envahissantes s’étendent dans les différents milieux qu’elles colonisent c’est permettre à la fois de mieux appréhender leurs impacts, de pouvoir de prédire leur expansion, et de trouver les endroits stratégiques où agir pour contrer ou atténuer les effets indésirables de ces espèces. Le problème est que dynamiques d’invasions d’une espèce regroupent en fait une hiérarchie de processus se produisant simultanément à différentes échelles spatiotemporelles et qui sont contrôlés par des facteurs qui changent en fonction du temps et du contexte d’invasion. Pour acquérir une compréhension profonde de ces dynamiques, il faut donc étudier leurs manifestations et leurs causes aux diverses échelles spatiales et temporelles auxquelles elles se produisent.Présentes sur les cinq continents et très envahissante sur au moins deux, les renouées asiatiques (Reynoutria spp.) sont reconnues comme faisant partie des espèces les plus invasives de la planète. Dotées d’une grande tolérance environnementale et d’importantes capacités de multiplication végétatives, ces plantes herbacées géantes peuvent former rapidement de grandes monocultures clonales qui excluent les autres espèces végétales, modifient les cycles biogéochimiques des zones envahies et perturbent diverses activités anthropiques. Cibles de campagnes de gestion depuis des décennies, elles affichent cependant une résilience insolente qui désespère de nombreux gestionnaires. Bien que très étudiées, de nombreux détails concernant leurs dynamiques nous échappent toujours. Dans ce travail de thèse, nous avons donc cherché à identifier quels sont les facteurs qui contrôlent les dynamiques spatiotemporelles des renouées à différentes échelles, et comment une meilleure compréhension de ces dynamiques clés pourrait profiter à leur gestion ?Pour ce faire, nous nous sommes donc d’abord intéressés à leur dynamiques clonales et à leurs variations en fonction de différentes conditions de stress (ombrage) ou de perturbation (fauchage répétée). Nous avons montré que si les renouées sont bien affectées par des conditions stressantes ou perturbées, cela ne les empêche ni de s’établir, ni de croître. En fait, les renouées semblent pouvoir adopter différentes stratégies de croissance pour pallier ces contraintes, soulevant différentes questions liées à la gestion. Dans une deuxième étude, nous avons cherché quels étaient les variables qui expliquaient l’expansion des taches de renouées le long d’un gradient altitudinal. Si nous avons montré que les dynamiques d’expansion des taches étaient principalement contrôlées par leur taille (et donc potentiellement leur âge) ainsi que par la proximité de routes et de rivières, nous avons également apporté des indices qui suggèrent que les renouées pourraient être potentiellement capables d’envahir les montagnes. Ensuite, pour tenter d’aider à résoudre le problème de l’acquisition des données de distribution des renouées à large échelle, nous avons développé une méthode pour détecter et cartographier les populations de renouées à partir d’images satellites et issues de drones. Notre méthode a montré des résultats encourageants et celle-ci pourrait être utile à l’étude des invasions ainsi qu’à la détection des nouveaux foyers d’invasion pour une gestion plus précoce et efficace des renouées.Enfin, nous avons tenté de dresser un portrait global de la compréhension actuelle des dynamiques d’invasion des renouées en réalisant, en guise de discussion, une grande revue de littérature sur les mouvements de ces plantes à travers les échelles spatiales et temporelles et en y intégrant les apports des autres travaux de cette thèse. / Although less mediatized than deforestation or climate change, biological invasions remain problematic for the conservation of many ecosystems and the maintenance of various socio-economical activities.Understanding the way invasive non-native species spread in their introduced range is enabling a better apprehension of their impacts, the possibility to predict their expansion, and the development of better management strategies. A problem is that a species invasion dynamics are actually composed of a hierarchy of processes occurring simultaneously at various spatiotemporal scales and which are controlled by drivers that are time- or context-dependent. To gain more profound insights into these dynamics, one has to study the patterns they create and their underlying processes at all relevant scales.Occurring on the five continents and highly invasive on at least two of them, Asian knotweeds (Reynoutria spp.) are acknowledged as being among the most invasive species in the world. Gifted with a large environmental tolerance and high abilities for vegetative multiplication, these giant herbaceous plants can quickly form large clonal monocultures that exclude the other plant species, modify biogeochemical cycles, and affect various anthropic activities. Target of management campaigns for decades, knotweeds display an insolent resilience to the great despair of many stakeholders. Despite having been extensively studied, many aspects of their dynamics are still elusive. Consequently, in this thesis, we have tried to highlight what the drivers of the spatiotemporal dynamics of knotweeds across scales are, and how their management could benefit from a better understanding of these dynamics?To answer these questions, we first focused our attention on the clonal dynamics of knotweeds and on their variations when they experience differing conditions in terms of light availability and disturbance (repeated mowing). We have shown that although shade or mowing affects the vigour and the development of clones, it does not prevent their establishment or their growth. In fact, knotweeds seem able to adopt different growth strategies to cope with environmental heterogeneity, suggesting some management avenues. In a second study, we tried to identify the drivers that controlled the expansion of knotweed stands along an elevational gradient. If we showed that the lateral expansion of stands is mostly constrained by their size (and thus, possibly their age) and the vicinity of roads and rivers, we also brought evidences that knotweeds could have the potential to invade mountain regions. Then, to help for the acquisition of large-scale datasets on knotweeds’ distribution, we developed a procedure to accurately detect and map knotweeds using satellite or drone imagery. Our results were quite encouraging and could be useful to both the basic research and to the detection of newly invaded areas, enabling earlier control operations and more efficient management.Finally, we tried to draw a full picture of the current knowledge on the invasion dynamics of knotweeds by reviewing the literature on the movement of these plants across spatial and temporal scales, to discuss and expand the reach of the insights gained in the various chapters of this thesis.

Orientador: Silvano Bianco / Resumo: O objetivo do estudo é a interação entre a tecnologia de mudas pré-brotadas (MPB) de cana-de-açúcar e o controle de plantas daninhas, especificamente do capim-camalote (Rottboellia cochinchinensis). Nesse compasso forão realizados cinco experimentos em ambiente aberto no Centro de Cana/IAC, utilizando as tecnologias de plantio por tolete, MPB IAC, Plene Evolve e Plene PB da cultivar IACSP95 5000 de cana-de-açúcar e sementes de capim-camalote. Dois experimentos na área de matocompetição, um sobre densidade do capim-camalote, e outro de distância do capim-camalote da MPB de cana-de-açúcar. Foram plantadas as MPB ao centro de vasos de 40 litros e depois distribuídos os tratamentos, diferentes densidades de capim-camalote (0, 1, 2, 4 e 8 plantas/vaso) e nos de distância, os tratamentos 7,5 e 15 cm da MPB. Eles seguirão o padrão de delineamento inteiramente casualizado em esquema fatorial com quatro repetições e foram analisadas aos 60 e 120 dias após o plantio (DAP) a altura, diâmetro e perfilhamento das plantas e a massa seca do capim-camalote e da cana-de-açúcar aos 120 DAA. Outros dois experimentos de tolerância foram instalados, um com os herbicidas em pré-plantio e outro em pós-plantio da cana-de-açúcar, os herbicidas testados foram os utilizados no tratamento convencional dos canaviais comerciais. Nesses experimentos foram analisadas aos 60, 90 e 120 DAA, os sintomas visuais de intoxicação, a altura, o diâmetro e perfilhamento das plantas; e 120 DAA, a massa seca do capim-c... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of the study is the interaction between sugarcane pre-sprouted seedling (MPB) technology and weed control, specifically of Rottboellia cochinchinensis. In this measure five experiments were conducted in open environment in the Center of Cana / IAC, using the technologies of tillage, MPB IAC, Plene Evolve and Plene PB of the sugarcane cv. IACSP95 5000 and seeds of itchgrass. Two experiments in the area of matocompetition, one on the density of the itchgrass, and the other one away from the sugarcane MPB itchgrass. The MPB were planted in the center of 40 liters pots and then the treatments, different densities of itchgrass (0, 1, 2, 4 and 8 plants/pot) were distributed and in the distance, the treatments 7.5 and 15 cm. of MPB. They will follow the completely randomized design in a factorial scheme with four replications and were analyzed at 60 and 120 days after planting (DAP) the plant height, diameter and tillering and the dry mass of itchgrass and sugarcane at 120 DAA. Two other tolerance experiments were installed, one with pre-planting and the other with post-planting sugarcane. The herbicides tested were those used in the conventional treatment of commercial sugarcane fields. In these experiments were analyzed at 60, 90 and 120 DAA, the visual symptoms of intoxication, plant height, diameter and tillering; and 120 DAA, the dry mass of itchgrass and sugarcane. Finally, a control experiment in pre-emergence of itchgrass will again use the recommended herbicides for... (Complete abstract click electronic access below) / Doutor

Orientador: Ricardo de Souza Cavalcante / Resumo: Introdução. A candidemia tem-se tornado cada vez mais frequente nos hospitais e apresentado elevada mortalidade. Conhecer a epidemiologia e os fatores prognósticos permite melhor manejo clínico desta infecção. Diante disto, este estudo teve por objetivo avaliar a incidência da candidemia em um hospital de ensino durante os últimos anos, a mortalidade, a prevalência das espécies causadoras da infecção, bem como os fatores prognósticos. Métodos. Este foi um estudo de coorte não concorrente, com pacientes atendidos no Hospital das Clínicas da Faculdade de Medicina de Botucatu (HCFMB), que apresentaram diagnóstico de candidemia durante sua internação, entre os anos de 2012 e 2019. Os dados clínicos foram obtidos a partir do prontuário médico. Para a avaliação dos fatores associados ao prognóstico, em análise univariada e múltipla, foi utilizado o modelo de Regressão Proporcional de Cox. Foram consideradas significativas as variáveis com valores de p inferiores a 0,05. Resultados. Ocorreram 314 episódios de candidemia em 288 pacientes. A taxa de incidência foi de 1,66/1000 admissões. A espécie mais prevalente foi Candida albicans (38,8%), seguida de complexo C. parapsilosis (20,4%), C. tropicalis (15,3%), C. glabrata (10,8%) e C. krusei (2,5%). Na população pediátrica houve predomínio de complexo C. parapsilosis (p<0,0001) e C. glabrata nos adultos (p=0,002). A taxa de mortalidade em 30 dias foi de 43,4%, sendo maior em adultos do que pacientes pediátricos (19,3% vs 54,0%; p<0,01)... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Introduction. Candidemia has become increasingly frequent in hospitals and has shown high mortality. Knowing the epidemiology and prognostic factors allows better clinical management of this infection. In view of this, this study aimed to evaluate the incidence of candidemia in a teaching hospital during the past few years, mortality, the prevalence of species causing the infection, as well as prognostic factors. Methods. Non-concurrent cohort study was carried out, with inpatients at the Hospital das Clínicas, Faculdade de Medicina de Botucatu (HCFMB), who presented a diagnosis of candidemia during their hospitalization, between the years 2012 and 2019. The clinical data were obtained from the medical records. For the assessment of factors associated with prognosis, in univariate and multiple analysis, the Cox Proportional Regression model was used. Variables with p values below 0.05 were considered significant. Results. There were 314 episodes of candidemia in 288 patients. The incidence rate was 1.66 / 1000 admissions. The most prevalent species was Candida albicans (38.8%), followed by C. parapsilosis complex (20.4%), C. tropicalis (15.3%), C. glabrata (10.8%) and C. krusei (2.5%). In the pediatric population, there was a predominance of the C. parapsilosis complex (p <0.0001) and C. glabrata in adults (p=0.002). The 30-day mortality rate was 43.4%, being higher in adults than pediatric patients (19.3% vs 54.0%; p<0.01). Independent factors of mortality were liver cirrhos... (Complete abstract click electronic access below) / Mestre

Orientador: Pedro Luis da Costa Aguiar Alves / Resumo: É prática comum durante o cultivo da cana-de-açúcar o uso de maturadores de forma antecipar a colheita. No entanto, considerando que pode haver cultivos próximos, como o de hortaliças, é importante ressaltar os cuidados necessários quando dá aplicação destes produtos, que é realizada por via aérea, a fim de evitar a deriva. Culturas sensíveis, como a da alface, podem sofrer efeitos deletérios. Sendo assim, objetivou-se com este trabalho avaliar o efeito da deriva dos maturadores glyphosate, trinexapac-ethyl e sulfometuron comumente utilizados em cana-de-açúcar no crescimento da alface ‘Lucy Brown’ e ‘Vanda’. O experimento foi instalado em ambiente aberto do Laboratório de Plantas Daninhas (LAPDA), UNESP/FCAV nos meses de outubro e novembro. Mudas de alface foram transplantadas para vaso com capacidade para 5 L, sendo cada planta a parcela experimental. O experimento foi constituído de 15 tratamentos estabelecidos no delineamento em blocos casualizados em esquema fatorial 3x5, com cinco repetições. O primeiro fator correspondeu aos maturadores e o segundo às subdoses, de forma a simular a deriva, sendo essas de 0, 3%, 6%, 9% e 12% da dose recomendada de cada produto, sendo aplicados quando as mudas apresentavam ao início da formação da cabeça, para a cultivar Lucy Brown e o estádio de 6 a 7 folhas para a cultivar Vanda. Após aplicação, as avaliações ocorreram aos 5, 10, 15 e 20 dias após aplicação (DAA). Foram realizadas avaliações visuais, com base na escala EWRC (1964), teor... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: It is common practice during the cultivation of sugarcane to use ripeners in order to anticipate the harvest. However, considering that there may be crops nearby, such as vegetables, it is important to emphasize the necessary care when applying these products, which is carried out by air, in order to avoid drifting. Sensitive crops, such as lettuce, can suffer deleterious effects. Therefore, the aim of this work was to evaluate the effect of the glyphosate, trinexapac-ethyl and sulfometuron ripening effects commonly used in sugarcane on 'Lucy Brown' and 'Vanda' lettuce growth. The experiment was installed in an open environment at the Laboratory of Weeds (LAPDA), UNESP / FCAV in the months of October and November. Lettuce seedlings were transplanted to a 5 L pot, each plant being the experimental plot. The experiment consisted of 15 treatments established in a randomized complete block design in a 3x5 factorial scheme, with five replications. The first factor corresponded to the ripeners and the second to the subdoses, in order to simulate the drift, being 0, 3%, 6%, 9% and 12% of the recommended dose of each product, being applied when the seedlings presented at the beginning of the head formation, for the Lucy Brown cultivar and the 6 to 7 leaf stage for the Vanda cultivar. After application, the evaluations occurred at 5, 10, 15 and 20 days after application (DAA). Visual evaluations were performed based on the EWRC scale (1964), chlorophyll content, quantum efficiency of ... (Complete abstract click electronic access below) / Mestre

Microbial infections are a major threat to public health particularly in developing countries due to the relative unavailability of medicine and the emergence of widespread drug resistance. Serious invasive fungal infections caused by Candida albicans, Cryptococcus neoformans and Aspergillus spp. represents an increasing threat to human health. They have increased significantly during the past decade, especially in immunocompromised individuals, due to the increased occurrence of HIV infections and resistance development. The toxicity of available antifungal drugs/agents has contributed greatly to the need for new antifungal drugs. Cryptococcus neoformans is a yeast organism that causes cryptococcosis in both humans and animals. This disease develops following inhalation and dissemination of the organism from the lungs to the central nervous system. Infection with C. neoformans often produces pneumonia and cryptococcal meningitis in HIV-infected patients. The problem with this fungus is that AIDS patients respond poorly to treatment and need lifelong therapy to suppress the infection and the drug treatment may be expensive in developing countries. This indicates an urgent need to develop new specific fungicidal antimicrobial agents for the treatment of cryptococcosis. Plants synthesize a large number of secondary metabolites for protecting themselves against microbe infections caused by bacteria, fungi and viruses. These substances may be useful in the treatment of microbial infections in humans and animals. Plants can be considered as potential sources of therapeutic extracts or active pure chemical compounds for the development of medicines. During this project, ten plant species (Zanthoxylum capenses, Morus mesozygia, Calodendron capenses, Catha transvaalensis, Cussonia zuluensis, Ochna natalitia, Croton sylvaticus, Maytenus undata, Celtis africana and Cassine aethiopica) were screened for activity against C. neoformans using both bioautography and the microdilution assay. The most active plant species was selected for the isolation of active metabolites. The selection of plant species was based on the lowest MIC value, presence of clear zones on bioautograms indicating antifungal activity, and high total activity against C. neoformans. M. undata indicated the presence of clear zones on bioautograms, a low average MIC value of 0.09 mg/ml and high total activity. C. sylvaticus and C. transvaalensis had lower or equal average MIC values to M. undata of 0.07 mg/ml and 0.09 mg/ml respectively. However a lack of clear bands to identify the position of active compounds on bioautography plates disqualified them for further analysis in this study. The leaves of M. undatawere exhaustively extracted with hexane, dichloromethane, acetone and methanol respectively. The hexane extract indicated the lowest MIC value of 0.02 mg/ml and was used for isolation of the active constituents. Column chromatography and bioassay-guided fractionation led to the isolation of six triterpene-like compounds.The structure of the isolated compounds was elucidated using the NMR and MS techniques and the compounds were identified as friedelin (1), epifriedelanol (2), taraxerol (3), 3-oxo-11á-methoxyolean-12-ene-30-oic acid (4), 3-oxo-11á-hydroxyolean-12-ene-30-oic acid (5)&3,11-dihydroxyolean-12-ene-30-oic acid (6). Friedelin (1) and epifriedelanol (2) belong to the friedelane group of triterpenoids, taraxerol (3) belongs to the taraxerane group and 3-oxo-11á-methoxyolean-12-ene-30-oic acid (4), 3-oxo-11á-hydroxyolean-12-ene-30-oic acid (5)&3,11-dihydroxyolean-12-ene-30-oic acid (6) belong to the 12-oleanene group. These groups have been isolated previously from plants that belong to the Celastraceae family. Four of the six isolated compounds 1,3,5 and 6 were isolated in sufficient quantity to be assayed against two fungal species (Candida albicans and Cryptococcus neoformans), two Gram-positive bacterial species (Staphylococcus aureus, ATCC 29213 and Enterococcus faecalis, ATCC 29212) and two Gram-negative bacterial species (Escherichia coli, ATCC 27853 and Pseudomonas aeruginosa, ATCC 25922).Two of the compounds, 3-oxo-11á-hydroxyolean-12-ene-30-oic acid (5)&3,11-dihydroxyolean-12-ene-30-oic acid (6), showed clear bands against all the tested organisms on bioautograms indicating microbial growth inhibition. MIC values ranged from 24 µg/ml to 63 µg/ml except for S. a ureus which was resistant. All the tested microorganisms showed resistance against friedelin (1) and taraxerol (3) with MIC values of >250 µg/ml, except for E. faecalis with an MIC value of 130 µg/ml for taraxerol. The cytotoxicity of the hexane extract and the isolated compounds were investigated using the tetrazolium-based colorimetric assay (MTT) using Vero monkey kidney cells and the hemagglutination assay using formaldehyde-fixed erythrocytes (RBCs). The hexane plant extract indicated toxicity towards the Vero monkey cells with an LC50 of 0.076 mg/ml. Compounds 1 and 3 indicated no toxicity against the cells with an LC50 greater than 200 µg/ml. However compounds 5 and 6 indicated toxicity with an LC50 of 6.16 µg/ml and 3.36 /ml, respectively. Also the hemagglutination assay indicates that hexane extract is toxic towards the RBCs with a HA titer value of 1.6. Both compounds 1 and 3 indicated no agglutination and compounds 5 and 6 indicated HA titer values of 1.33 and 0.67, respectively. / Dissertation (MSc)--University of Pretoria, 2007. / Paraclinical Sciences / unrestricted