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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

Seletividade de herbicidas aplicados nas culturas do milho e do eucalipto em insetos de controle biol?gico. / Selectivity of herbicides applied in maize and eucalyptus under insect of biological control.

Menezes, Claubert Wagner Guimar?es de 11 July 2012 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-27T13:30:35Z No. of bitstreams: 5 48.pdf: 312989 bytes, checksum: d64deaf4dec63e71c21cf34cb462dbbf (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-27T19:04:02Z (GMT) No. of bitstreams: 5 48.pdf: 312989 bytes, checksum: d64deaf4dec63e71c21cf34cb462dbbf (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Made available in DSpace on 2015-02-27T19:04:05Z (GMT). No. of bitstreams: 5 48.pdf: 312989 bytes, checksum: d64deaf4dec63e71c21cf34cb462dbbf (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) Previous issue date: 2012 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes) / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / O manejo das plantas daninhas ? necess?rio nas culturas agr?colas para que se evite a competi??o e perdas na produ??o. O uso de herbicidas ? comum no controle das plantas daninhas, e pode causar impacto negativo ao meio ambiente. O objetivo desse trabalho foi avaliar a seletividade de herbicidas, aplicados nas culturas do milho e do eucalipto, sobre os insetos de controle biol?gico de pragas Podisus nigrispinus Dallas, 1851 (Heteroptera Pentatomidae) e Palmistichus elaeisis Delvare & LaSalle, 1993 (Hymenoptera: Eulophidae). Foram realizados tr?s experimentos em laborat?rio. No primeiro, avaliou-se a seletividade dos herbicidas atrazine e nicosulfuron e a mistura destes, e mais o controle (?gua), aplicados em posturas e em diferentes est?dios biol?gicos de P. nigrispinus. A viabilidade dos ovos de P. nigrispinus diminuiu sob a??o dos herbicidas, sem diferirem quanto ao tempo de eclos?o. A sobreviv?ncia de ninfas foi baixa sob a??o dos herbicidas, sendo mais afetada negativamente com a mistura de herbicidas. Para a aplica??o em cada est?dio, observou-se baixa sobreviv?ncia de ninfas do primeiro ao terceiro est?dios com o herbicida atrazine isolado, ou em mistura, e at? o segundo est?dio para o nicosulfuron. Observou-se em todos os demais est?dios do inseto a menor seletividade ? mistura dos herbicidas comparados ao efeito isolado. O segundo experimento avaliou-se a seletividade de herbicidas registrados para a cultura do milho para o inimigo natural P. elaeisis. Os tratamentos foram pupas do hospedeiro alternativo Tenebrio molitor Linnaeus, 1758 (Coleoptera: Tenebrionidae) pulverizadas com os herbicidas atrazine, nicosulfuron, paraquat e tembotrione, na dose comercial, mais o tratamento controle com ?gua. Pupas de T. molitor foram submergidas em solu??o herbicida e logo ap?s, expostas ao parasitismo por seis f?meas de P. elaeisis. Os herbicidas atrazine e paraquat n?o foram seletivos a P. elaeisis, apresentando elevada toxicidade. J? o herbicida nicosulfuron reduziu a raz?o sexual de P. elaeisis, o que pode comprometer as gera??es subsequentes. O herbicida tembotrione foi seletivo a P. elaeisis apresentando menor risco quando indicado em programas de manejo integrado de insetos. No terceiro experimento avaliou-se a seletividade de herbicidas usados na cultura do eucalipto no parasitoide P. elaeisis. Os tratamentos constaram das doses comerciais dos herbicidas sulfentrazone, oxyfluorfen, glyphosate, glufosinato sal de am?nio e isoxaflutole, al?m do controle, apenas com ?gua. Os herbicidas foram aspergidos em pupas do hospedeiro alternativo T. molitor, as quais foram expostas ao parasitismo por seis f?meas de P. elaeisis. Os herbicidas glufosinato sal de am?nio e oxyfluorfen n?o foram seletivos ?s f?meas de P. elaeisis, e reduziram o parasitismo e a emerg?ncia desse parasitoide. O n?mero de indiv?duos e f?meas produzidas por f?mea foram maiores com isoxaflutole, portanto apresentando menor risco quando utilizado em programas de manejo integrado de pragas na cultura do eucalipto. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2012. / ABSTRACT The management of weeds in agricultural crops is necessary to avoid competition and yield losses. Herbicide use is common in weed control, and can negatively impact the environment. The aim of this study was to evaluate the toxicity of herbicides applied on corn [Zea mays L. (Poaceae)] and eucalyptus [Eucalyptus sp. (Myrtaceae)] on the Podisus nigrispinus Dallas, 1851 (Heteroptera Pentatomidae) and Palmistichus elaeisis Delvare & LaSalle, 1993 (Hymenoptera: Eulophidae). Three experiments were conducted in the laboratory. At first, we evaluated the selectivity of the herbicides atrazine and nicosulfuron and mixture, in commercial dosage, applied in different postures and biological stages of P. nigrispinus. The viability of eggs of P. nigrispinus decreased under the action of herbicides, without differences regarding the time of hatching. The survival of nymphs was low in the herbicides being more adversely affected with the herbicide mixture. For the application at each stage there was low survival of nymphs of the first to third stage with the herbicide atrazine, alone or in mixture until the second stage to nicosulfuron. It was observed in all other stages of the insect to lower selectivity compared to the herbicide mixture to the isolated effect. The second chapter assessed the selectivity of herbicides registered for corn for the natural enemy of P. elaeisis. The treatments were pupae of the alternative host Tenebrio molitor Linnaeus, 1758 (Coleoptera: Tenebrionidae) sprayed with the herbicide atrazine, nicosulfuron, paraquat and tembotrione in commercial dosage over the control treatment with water. Pupae of T. molitor were overwhelmed with the solution herbicidica and soon after exposed to parasitism by six females of P. elaeisis. The herbicides atrazine and paraquat were not selective to P. elaeisis, with high toxicity. The herbicide nicosulfuron reduced the sex ratio of P. elaeisis, which may affect subsequent generations. The herbicide tembotrione was selective to P. elaeisis and can be displayed in integrated pest management of insects. In the third chapter we evaluated the selectivity of herbicides used in the cultivation of eucalyptus, to the parasitoid, P. elaeisis. The treatments consisted of doses of commercial herbicides sulfentrazone, oxyfluorfen, glyphosate, glufosinate ammonium salt and isoxaflutole, beyond control, with water only. The herbicides were sprayed in pupae of the alternative host T. molitor, which were exposed to six female parasitism by P. elaeisis. The herbicide glufosinate ammonium salt and oxyfluorfen were not selective in females of P. elaeisis, and reduced parasitism and emergence of this parasitoid. The number of individuals and females produced per female were higher with glyphosate and isoxaflutole and can be used in programs of Integrated Pest Management (IPM) in the culture of eucalyptus.
2

Desenvolvimento de artr?podes n?o alvos e estresse fisiol?gico em algodoeiro geneticamente modificado expressando as prote?nas CRY1F e CRY1AC / Development of non-targeted arthropods and physiological stress in genetically modified cotton expressing CRY1F and CRY1AC proteins

Valadares, Nermy Ribeiro 17 February 2017 (has links)
?rea de concentra??o: Manejo integrado de pragas. / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-07-24T19:32:10Z No. of bitstreams: 2 nermy_ribeiro_valadares.pdf: 721013 bytes, checksum: 6f53437940ebff37fcc6b98c4109987e (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-07-28T18:01:04Z (GMT) No. of bitstreams: 2 nermy_ribeiro_valadares.pdf: 721013 bytes, checksum: 6f53437940ebff37fcc6b98c4109987e (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-07-28T18:01:04Z (GMT). No. of bitstreams: 2 nermy_ribeiro_valadares.pdf: 721013 bytes, checksum: 6f53437940ebff37fcc6b98c4109987e (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017 / O Brasil ? um dos maiores produtores mundiais de algod?o, n?o apenas em volume, mas tamb?m em qualidade e inova??o. Por?m, o ataque de insetos pragas ? um dos principais entraves para a produtividade das lavoras de algod?o, o que ? acentuado pelas grandes ?reas de monocultivo. Uma das t?ticas de manejo que est? sendo empregada ? a resist?ncia de plantas. A cultura hospeda diversos organismos, dentre eles um grande n?mero de artr?podes como o pulg?o Aphis gossypii Glover 1877 (Hemiptera: Aphididae) e o ?caro fit?fago Tetranychus ludeni zacher, 1913 (Acari: Tetranychidae), que se alimentam da parte a?rea das plantas, podendo causar preju?zos econ?micos. As variedades transg?nicas utilizadas no manejo de pragas s?o desenvolvidas para controlar determinado grupo de insetos, de acordo com a toxina que expressam. Por?m ao serem expressas continuamente, essas toxinas ficam expostas aos demais herb?voros que se hospedam na planta, surgindo uma preocupa??o de que o uso em larga escala desta tecnologia possa ter efeitos adversos sobre artr?podes n?o alvos. O impacto das prote?nas Bt em artr?podes n?o visados ? menos compreendido do que os seus efeitos nos organismos alvos, onde o mecanismo da a??o t?xica ? conhecido. H? pouca informa??o sobre efeitos de transg?nicos Bt sobre popula??es de pulg?es e ?caros, e sobre o estresse causado pelo ataque desses artr?podes. Com isso, esse trabalho teve por objetivo avaliar o desenvolvimento de organismos n?o alvos em algod?o geneticamente modificado. E avaliar o estresse fisiol?gico causado pelo ataque de ?caros e pulg?es em algod?o transg?nico e convencional. De acordo com os resultados obtidos ? poss?vel concluir que as toxinas Cry1F e Cry1Ac n?o exercem qualquer efeito no desenvolvimento do T. ludeni, e que o algod?o Bt foi menos infestado por A. gossypii. A severidade da infesta??o desses artr?podes causa altera??es nos par?metros da fluoresc?ncia da clorofila, promovendo estresse fisiol?gico nas plantas, tanto do algod?o Bt como da isolinha. Coletivamente, esses resultados fornecem fortes evid?ncias de que a tecnologia Bt pode complementar outras t?ticas integradas de controle de pragas, especialmente se em conjunto com o controle biol?gico. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / Brazil is one of the world's largest cotton producers, not only in terms of volume but also in quality and innovation. However, insect pest attack is one of the main barriers to cotton productivity, which is accentuated by large areas of monoculture. One of the management tactics that is being used is the resistance of plants. The culture hosts several organisms, including a large number of arthropods such as the aphid Aphis gossypii Glover 1877 (Hemiptera: Aphididae) and the phytophagous spider mite Tetranychus ludeni zacher, 1913 (Acari: Tetranychidae), which feed on the aerial part of the plants. Cause economic losses. The transgenic varieties used in pest management are developed to control a particular group of insects, according to the toxin they express. However, when expressed continuously, these toxins are exposed to other plant-eating herbivores, raising concerns that large-scale use of this technology may have adverse effects on non-target arthropods. The impact of Bt proteins on non-target arthropods is less understood than its effects on target organisms where the mechanism of toxic action is known. There is little information on the effects of Bt transgenics on populations of aphids and mites, and on the stress caused by the attack of these arthropods. The objective of this work was to evaluate the development of non-target organisms in genetically modified cotton and to evaluate the physiological stress caused by the attack of spider mites and aphids in transgenic and conventional cotton. According to the results obtained it is possible to conclude that the toxins Cry1F and Cry1Ac have no effect on the development of T. ludeni, and that Bt cotton was less infested by A. gossypii. The severity of the infestation of these arthropods causes changes in chlorophyll fluorescence parameters, promoting plant Physiological stress in both Bt cotton and isoline. Collectively, these results provide strong evidence that Bt technology can complement other integrated pest control tactics, especially if coupled with biological control.

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