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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.
131

Ecology and biological control of an apomictic invasive plant, Chondrilla juncea (Asteraceae) /

Campanella, Donald Michael. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 112-121). Also available on the World Wide Web.
132

RESÍDUOS DE FUNGICIDAS EM VINHOS DE DIFERENTES PROPRIEDADES VITIVINÍCOLAS DO RIO GRANDE DO SUL, BRASIL, FRENTE AO USO DA TECNOLOGIA THERMAL PEST CONTROL A CAMPO / FUNGICIDE RESIDUES IN WINES OF WINE PROPERTIES OF RIO GRANDE DO SUL, BRAZIL, REGARDING THE USE OF THERMAL PEST CONTROL TECHNOLOGY IN THE FIELDS

Mozzaquatro, Joseane de Oliveira 06 March 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The use of chemical compounds in the wine industry is extremely high, thus, it is appropriate to identify and quantify pesticide residues in wine because grapes are one of the fruits with the highest number of pesticide applications in the country's agriculture. In order to reduce the use of pesticides, some winemakers have been using the Thermal Pest Control (TPC) technology in the management of their vineyards as an alternative to control pests. It is a technology that provides the high temperatures vines, providing a greater antimicrobial resistance. The objective of this study was to identify and quantify fungicides in white and red wines produced from grapes with and without the use of TPC technology for their cultivation in different wine properties of Rio Grande do Sul. Samples of Tannat, Chardonnay and Cabernet Sauvignon varieties from the 2011/2012, 2012/2013 and 2013/2014 harvests were collected in three wine properties of RS. Vinification process was performed in laboratory scale separately for grapes using no TPC technology (control) and grapes using TPC (TPC). The modified QuEChERS acetate method was used for sample preparation. Afterwards, analyzes were carried out using UHPLC-MS/MS for determination of fungicides. Boscalid, procymidone, pyraclostrobin, pyrimethanil, thiophanate-methyl and tetraconazole were detected above the LOQ in both treatments. In control and with TPC, pyrimethanil presented higher frequency (85.71%) and averages (26.33 and 30.16 μg L-1), respectively. There was no significant difference between the white and red wines. In Chardonnay wines, 2012/2013 harvests, the fungicide pyrimethanil was statistically different, with an average of 64.67 μg L-1 (control), and 111.12 μg L-1 (TPC), thus, higher levels for wines with the use of TPC technology were observed. In Chardonnay wines, 2013/2014 harvests, showed the higher average of procymidone in control (6.47 μg L-1) than in treatment with TPC (0.46 μg L-1). In Cabernet Sauvignon wines, 2013/2014 harvests, presented a higher average of procymidone in treatment with TPC (129.73 μg L-1) than in control (3.69 μg L-1). Therefore, the presence of fungicide residues was observed in this study, but none of the compounds presented levels above the MRL established for grapes considering their mass corrections. These results show higher concentrations of residues for those wines produced from grapes submitted to TPC technology. We found no references in literature about fungicide residues in wine whose grapes were submitted to this technology, which leads us to believe this is the first study on the subject. / O uso de compostos químicos em vitivinicultura é extremamente elevado. Neste sentido, torna-se oportuno identificar e quantificar resíduos de pesticidas em vinhos, pois as uvas figuram a lista de maior número de aplicações de pesticidas na agricultura do país. Com intuito de reduzir o uso de pesticidas, alguns vitivinicultores utilizam a tecnologia Thermal Pest Control (TPC) no manejo de seus vinhedos, como forma alternativa no combate às pragas. Trata-se de uma tecnologia que gera e fornece elevadas temperaturas às videiras, conferindo uma maior resistência microbiana. O objetivo deste estudo foi identificar e quantificar fungicidas em vinhos brancos e tintos, oriundos de diferentes propriedades vitivinícolas do Rio Grande do Sul, produzidos a partir de uvas com e sem o emprego da tecnologia TPC durante o seu cultivo. Foram cedidas amostras das variedades Tannat, Chardonnay e Cabernet Sauvignon nas safras 2011/2012, 2012/2013 e 2013/2014. Realizaram-se vinificações em escala laboratorial e separadamente para aquelas uvas sem o emprego da tecnologia TPC (controle) daquelas que fizeram uso desta (com TPC). No preparo das amostras utilizou-se o método QuEChERS acetato modificado. Após, as análises procederam-se em UHPLC-MS/MS para determinação dos fungicidas. Boscalida, procimidona, piraclostrobina, pirimetanil, tetraconazol e tiofanato-metílico foram detectados acima do LOQ em ambos os tratamentos. Nos tratamentos, controle e com TPC, o pirimetanil obteve maior frequência (85,71%) e médias (26,33 e 30,16 μg L-1), respectivamente. Não houve diferença significativa para os dois tipos de vinhos (tintos e brancos). Nos vinhos da cv. Chardonnay, safra 2012/2013, o fungicida pirimetanil diferiu estatisticamente (p=0,021), com média de 64,67 μg L-1 (controle), e de 111,12 μg L-1 (com TPC), apresentando níveis superiores para os vinhos com a utilização da tecnologia TPC. Já nos vinhos da cv. Chardonnay, safra 2013/2014, o procimidona apresentou média superior no controle (6,47 μg L-1), do que no tratamento com TPC (0,46 μg L-1). E nos vinhos da cv. Cabernet Sauvignon, safra 2013/2014, cujas uvas foram produzidas na propriedade vitivinícola C‟, o composto procimidona obteve média superior para o tratamento com TPC (129,73 μg L-1), do que em relação ao controle (3,69 μg L-1). Diante do exposto, a presença de resíduos de fungicidas foi confirmada neste estudo, porém nenhum dos compostos mostrou-se acima dos LMRs estabelecidos para as uvas, considerando suas correções de massa. Tais resultados demonstraram concentrações de resíduos superiores para aqueles vinhos produzidos a partir de uvas submetidas à tecnologia TPC. Não foram encontradas referências na literatura que abordem resíduos de fungicidas em vinhos, cujas uvas fossem submetidas a esta tecnologia, o que nos leva a deduzir que este seja o primeiro estudo realizado sobre o tema.
133

Application of RNA Interference for the Study of Lethal Genes and Dynamic Processes

Ulrich, Julia 20 July 2015 (has links)
No description available.
134

Cricket Management

Bradley, Lucy, Gibson, Roberta 04 1900 (has links)
2 pp. / Indian house crickets and field crickets are the two most common crickets in Arizona. Although these crickets do not bite or carry diseases, they are considered a nuisance because of their "chirping". This publication focuses on common crickets found in Arizona, including the Indian house crickets, field crickets, and Jerusalem crickets. It also discusses the problems they cause and the strategies to control them.
135

Alfalfa Herbicide Trial Greenlee County, 1989

Clark, L. J., Heathman, E. S., DeRosa, E., Cluff, R. E. 09 1900 (has links)
Replicated herbicide experiments were carried out on alfalfa fields in Graham and Greenlee counties in the winter of 1989. Five herbicides were tested; tanzy mustard and (oxtail barley were the mails target weed species. Velpar L applied on at a rate of 4 pints per acre in 20 gallons of water provided the best control with 99% control of the broad -leafed weeds and 86% of the grassy weeds just prior to the first cutting. Better control of foxtail barley probably would have been achieved by several of the herbicides if they had been applied earlier, before the weeds germinated and /or if the materials had been incorporated by an adequate irrigation or rainfall.
136

Effect of Fungicides on Development of Cercospora Summer Black Stem and Leaf Spot in Alfalfa

Matheron, M., Winans, S., Rethwisch, M. 09 1900 (has links)
Cercospora summer black stem and leaf spot, a fungal disease of alfalfa, has been associated with a stand decline problem in La Paz County. In a continuation of a study initiated in 1987, we examined the ability of three fungicides to control the disease and decline problem. Bravo, Funginex, and Kocide significantly reduced the severity of Cercospora summer black stem and leaf spot. In addition, significant increases in yield were recorded on plots treated with fungicides.
137

Influence of predator and food chemical cues in the behaviour of the house mouse (Mus musculus)

Grau Paricio, Carlos 11 January 2019 (has links) (PDF)
Rodent commensal species produce great damage in agriculture and urban areas. As invasive species they can endanger local species and are carriers and vectors of several important zoonoses. Control methods rely mainly on the use of warfarins, which can be inadvertently be taken up by untargeted species. Warfarins have also lost their efficacy in rodents due to the development of genetic resistance. In addition, these methods are considered inhumane as they cause a slow and painful death due to haemorrhages. Olfaction is a main source for environmental risk assessment by rodents, and it can be used to modify their use of space. My aim in this thesis was to identify behavioural reactions of the house mouse (Mus musculus), using laboratory strains as models of wild animals, to ecologically meaningful chemical messages, including predator and plant chemical olfactory cues. My results showed that mice avoided complex ferret olfactory cues and ethanol which is a ubiquitous chemical related to fruit rotting and ripening. The feline protein Fel d 1, which belongs to the secretoglobin family and is a major cat allergen in humans, did not elicit significant avoidance or alter foraging behaviour in mice. However, Trimethylthiazoline purified from fox faeces, elicited clear avoidance behaviour and stress responses. I carried out a bibliographic review to evaluate and discuss rodent pest control methods from an ethical standpoint. This literature showed that many of the current methods of pest control are considered inhumane, and do not tally with current society concerns and welfare standards in other domains such as farms or laboratory animals. These results raise new research questions to identify ferret and plant chemical compounds that can induce rodent avoidance, and to carry out next stage of research with wild animals both under laboratory and field conditions.
138

Uso de geoestatística para aprimorar o controle de pragas na citricultura. / Use of geoestatistical to improve the pests control in citrus plants.

Okumura, Miriam Harumi 24 October 2007 (has links)
A preocupação com o desenvolvimento de novas tecnologias que priorizem o menor impacto ambiental, é cada vez maior. Esta tendência também ocorre na agroindústria, onde a preocupação com a redução de uso de defensivos agrícolas já é grande. Os problemas fitossanitários sempre foram barreiras que impediram o desenvolvimento da produtividade da citricultura, apenas ácaro da leprose (Brevipalpus phoenicis) representa cerca de 80 % dos custos destinados ao controle de pragas. O desenvolvimento de novas tecnologias, que colaborem com o controle de pragas e doenças já existentes, e outras que podem surgir, são uma necessidade deste setor. Nesta pesquisa foram utilizadas ferramentas informatizadas, utilizadas com sucesso no setor mineiro, no estudo dos ácaro da falsa ferrugem (Phyllocoptruta oleiva), ácaro branco (Plyphagotarsonemus latus) e ácaro da leprose (Brevipalpus phoenicis) com o objetivo de aprimorar o planejamento e gerenciamento da aplicação localizada de defensivos agrícolas, permitindo a verificação das variações espaciais e temporais dos fatores relacionados ao controle dessas pragas que prejudicam a produção citrícola. Estas ferramentas possuem análises geoestatísticas, que são primordiais para a modelagem espacial de fenômenos naturais, como as pragas e doenças, com características regionalizadas, a partir de amostras georreferenciadas. Como resultado tem-se a melhoria do processo de tomada de decisões na utilização de insumos agrícolas (defensivos), a partir do desenvolvimento de metodologia específica, testada e calibrada junto a um importante empreendimento no interior de São Paulo. / There is a great concern nowadays with the development of new technologies that prioritize environmental impact. This trend also occurs in the agribusiness, where one of the main concerns is the reduction in the use of agrochemicals. Phytosanitary issues have traditionally been a barrier for the increase in productivity of the citrus plants, as the leprosis mite (Brevipalpus phoenicis) responds for approximately 80 % of the pests control costs. The development of new technologies to control existing pests and diseases that affect citrus production is a major challenge of the agribusiness. In this research, software successfully developed for the mining industry has been applied to model the spatial distribution of citrus rust mite (Phyllocoptruta oleiva), broad mite (Plyphagotarsonemus latus) and leprosis mite (Brevipalpus phoenicis) with the objective of improving the planning and management of the localized application of agrochemicals. The resulting analysis have allowed the measurement of spatial variations of these pests and diseases. The spatial variation has then been used as the basis for planning the controlled application of agrochemicals for these pests and diseases. The research has applied geostatistical analysis for the detailed modeling of the regionalized behaviour of citrus pests and diseases according to the spatial positions of the field samples. The results obtained in the research include the improvement of the decisionmaking process of planning the application of agrochemicals and the development of a specific methodology which has been tested and calibrated in a test-implementation at an important agribusiness company in São Paulo.
139

Simbiontes de insetos como endofíticos: a interação Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) - Zea mays L. (Poales: Poaceae) / Symbionts of insects as endophytes: the interaction Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) - Zea mays L. (Poales: Poaceae)

Achre, Diandra 15 February 2018 (has links)
Insetos representam a maioria dos seres vivos na Terra. O sucesso biológico desses organismos está, em parte, relacionado às associações com microrganismos que influenciam aspectos de sua bioecologia, incluindo as relações com o primeiro e terceiro níveis tróficos. Assim como os insetos, plantas também apresentam associações com microrganismos que podem interferir na sua nutrição e relação com patógenos e herbívoros. Esse trabalho buscou analisar a capacidade de simbiontes associados a insetos de atuar como endofíticos de planta e influenciar, assim, o potencial biótico da planta e a sua capacidade de defesa contra a herbivoria, utilizando o modelo milho - Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae). Quatro simbiontes de insetos foram selecionados. Três deles (IIL-Sfm05, IILSfc-sus01 e IIL-Sfb05) associados ao trato digestivo de S. frugiperda e outro (IIL-ASP45) de Acromyrmex coronatus (IIL-ASP45). Adicionalmente, um endofítico (IILzm-Idp03) isolado do próprio milho foi adicionado como controle positivo. Os ensaios foram conduzidos após cultivo de sementes inoculadas com os diferentes microrganismos via bio-priming, aplicação no solo e aplicação foliar. Dos cinco isolados testados, três (IILSfc-sus01, IIL-Sfb05 e IILzm-Idp03) induziram maior crescimento em plantas de milho; porém, a forma de disponibilização dos microrganismos influenciou a resposta da planta. O isolado IILzm-Idp03 induziu o maior crescimento da planta pela sua disponibilização via bio-priming; IILzm-Idp03 e IIL-Sfb05 via inoculação do solo; e o isolado IILSfc-sus01 via inoculação foliar. Testes biológicos com S. frugiperda em plantas de milho inoculadas ou não com os microrganismos selecionados indicaram que dois deles (isolados IIL-Sfb05 e IIL-ASP45) resultaram em relações patogênicas, chegando à induzir a completa mortalidade de insetos alimentados em tecidos foliares de plantas inoculadas com esses microrganismos. Testes de preferência alimentar demonstraram que as lagartas não foram influenciadas pela alimentação com folhas de plantas inoculadas com as bactérias via bio-priming. Estudos comparativos dos índices nutricionais de plantas tratadas com as diferentes bactérias, indicaram que aquelas tratadas com IIL-ASP45 resultaram no menor crescimento e desenvolvimento larval de S. frugiperda, corroborado pelo menor consumo e índices nutricionais alcançados nessa fonte de alimento. A alimentação em plantas tratadas com IIL-Sfb05 causou 100% de mortalidade larval, não sendo possível a avaliação dos índices nutricionais. Os resultados desse trabalho demonstram o potencial de manipulação da planta hospedeira por bactérias associadas ao herbívoro, bem como o potencial biocida de microrganismos associados a insetos. / Insects represent most of the living things on Earth. The biological success of these organisms is in part related to associations with microorganisms that influence aspects of their bioecology, including relationships with the first and third trophic levels. Like insects, plants also have associations with microorganisms that may interfere in their nutrition and interactions to pathogens and herbivores. This work sought to assess the potential of symbionts associated with insects to act as plant endophytes and thus to influence plant growth and its utilization by the herbivory using the maize - Spodoptera frugiperda (JE Smith, 1797) (Lepidoptera: Noctuidae) model system. Four insect symbionts were selected. Three of them (IIL-Sfm05, IILSfc-sus01 and IIL-Sfb05) associated with the digestive tract of S. frugiperda and another (IIL-ASP45) with the cuticle of Acromyrmex coronatus (IIL-ASP45). Additionally, an endophyte (IILzm-Idp03) from maize was added as a positive control. Experiments were conducted after inoculation of the different microorganisms via bio-priming, soil application and foliar application. Of the five isolates tested, three (IILSfc-sus01, IIL-Sfb05 and IILzm-Idp03) induced higher growth in maize plants; however, the inoculation of the seeds with the microorganisms influenced the plant response. The isolate IILzm-Idp03 induced the highest plant growth when inoculated via bio-priming; IILzm-Idp03 and IIL-Sfb05 via soil inoculation; and IILSfc-sus01 via foliar inoculation. Biological tests with S. frugiperda on maize plants inoculated or not with the selected microorganisms indicated that two of them (IIL-Sfb05 and IIL-ASP45 isolates) were highly pathogenic, inducing very high larval mortality. Our analysis indicated no changes in larval feeding preference. Comparative analysis of larval food consumption and utilization indicated that plants inoculated with IIL-ASP45 resulted in the lowest growth and larval development of S. frugiperda, corroborated by the lower consumption and nutritional indexes reached in this food source. Feeding in plants inoculated with IIL-Sfb05 caused 100% larval mortality, and it was not possible to evaluate the nutritional indexes. Our data demonstrate the potential for manipulation of the host plant by bacteria associated with the herbivore, as well as the biocidal potential of insect - associated microorganisms.
140

Identificação de métodos e produtos utilizados, bem como o perfil das empresas especializadas no controle de vetores e pragas urbanas, com ênfase em percevejos de cama (hemiptera:cimicidae) / Identification of Methods and Products Used, as well as the Profile of the Pest Control Companies, with Emphasis on Bed Bugs (Hemiptera: Cimicidae)

Bocalini, Sérgio dos Santos 13 October 2015 (has links)
Os percevejos de cama são insetos pertencentes a ordem Hemiptera e a família Cimicidae, com metamorfose hemimetábola, possuem comportamento antropofílico e exercem a hematofagia nas fases de ninfa e adulto, o que desperta interesse em saúde pública. O reaparecimento desta praga tem levado diversas pessoas a buscarem nas empresas especializadas uma forma de exercer o controle. O presente estudo teve como objetivo identificar, no período de maio de 2013 a maio de 2015, as formas de controle e produtos utilizados, bem como o perfil das empresas especializadas no controle de vetores e pragas urbanas instaladas no Brasil. O estudo foi realizado por meio de uma enquete enviada a 2136 empresas brasileiras e questionário eletrônico enviado para as empresas. Foram encaminhadas 2136 cartas convites para participação. Como resultado foi obtido 158 enquetes respondidas e estas empresas foram então convidadas a responder um questionário com perguntas direcionadas ao controle de percevejos de cama. Apenas 13 questionários foram recebidos de empresas localizadas na região Sul, Sudeste, Centro-Oeste e Nordeste. A maioria das empresas que realiza o controle de percevejos de cama está na área de controle de pragas urbanas a mais de 21 anos e utiliza preferencialmente pesticidas para o controle dos insetos. Quase 50 por cento dos responsáveis técnicos dessas empresas não fizeram qualquer treinamento sobre controle de cimicídeos nos últimos dois anos e informações sobre o inseto e seu manejo não são passadas ao cliente. O baixo retorno dos questionários preenchidos nesta pesquisa pode ser devido ao pouco conhecimento que as empresas têm sobre o controle de percevejos de cama, o que pode tê-las inibido em fornecer informações. Desta maneira, informações técnicas e treinamentos sobre o controle de percevejos de cama se faz necessário, uma vez que o controle ainda está pautado na utilização de produtos químicos e que esta estratégia pode incorrer em riscos de intoxicação quando feita de maneira inadequada principalmente pela falta de capacitação dos responsáveis técnicos. / Bed bugs belong to the order Hemiptera and family Cimicidae with hemimetabolous metamorphosis; they show anthropophilic behavior and are hematophagous at nymph and adult stages, which causes interest in public health. The reappearance of this pest has led many people to seek for pest control companies to control it. This study aimed to identify, from May 2013 to May 2015, which are the control strategies and used products as well as the profile of the pest control companies in Brazil. The study was made through an electronic survey sent to 2136 Brazilian companies, One hundred and fifty eight companies answered the survey and were invited to fill in a questionnaire on bed bug control. Only 13 questionnaires were received from companies located in the South, Southeast, Midwest and Northeast regions of Brazil. Most companies that make bed bug control are in the area for more than 21 years and they use mainly pesticides to control the insects. Almost 50 per cent of the technical managers of these companies did not attend to any training on bed bug control in the last two years, and information on their management is not given to their clients. The few questionnaires received are probably due to the little knowledge that pest control companies have on bed bugs, which may have inhibited them to provide information. In this way, technical information and training on the bed bug control is necessary, since the control is still founded on the use of chemicals and that this strategy may incur intoxication risk when done improperly mainly by lack of training of technical experts.

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