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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.
151

A DNA-based approach to study predator-prey trophic interactions within Brassica crops : a search for predators of diamondback moth (Plutella xylostella).

Hosseini, Reza January 2007 (has links)
Title page, contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / Brassica vegetables and oilseeds are economically important crops worldwide. These crops are associated with several destructive and widespread insect pests. In Australia these pests include six species, Plutella xylostella (Linnaeus), Pieris rapae (Linnaeus), Hellula hydralis Guenée, Helicoverpa punctigera (Wallengren), Brevicoryne brassicae (Linnaeus) and Myzus persicae (Sulzer), which are the focus of this research. Among them P. xylostella (diamondback moth or DBM) is the most serious and destructive insect pest. Little is known about the potential of predators, which may be able to contribute to control diamondback moth, although some field studies have shown the overall importance of predators in controlling this key pest. The aim of this study was to develop a method that allows study of predator-prey trophic interactions in the field. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1294814 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2007
152

Patch exploitation by the parasitoids of Plutella xylostella (L.): from individual behaviour to population dynamics / Xin-geng Wang.

Wang, Xin-geng January 2001 (has links)
Includes bibliographical references (leaves 204-230). / xvi, 230 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Investigates the behaviour and ecology of the two major larval parasitoids of the diamondback moth, Plutella xylostella; Cotesia plutellae and Diadegma semiclausum. / Thesis (Ph.D.)--University of Adelaide, Dept. of Applied and Molecular Ecology, 2001
153

A DNA-based approach to study predator-prey trophic interactions within Brassica crops : a search for predators of diamondback moth (Plutella xylostella).

Hosseini, Reza January 2007 (has links)
Title page, contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / Brassica vegetables and oilseeds are economically important crops worldwide. These crops are associated with several destructive and widespread insect pests. In Australia these pests include six species, Plutella xylostella (Linnaeus), Pieris rapae (Linnaeus), Hellula hydralis Guenée, Helicoverpa punctigera (Wallengren), Brevicoryne brassicae (Linnaeus) and Myzus persicae (Sulzer), which are the focus of this research. Among them P. xylostella (diamondback moth or DBM) is the most serious and destructive insect pest. Little is known about the potential of predators, which may be able to contribute to control diamondback moth, although some field studies have shown the overall importance of predators in controlling this key pest. The aim of this study was to develop a method that allows study of predator-prey trophic interactions in the field. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1294814 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2007
154

Control of the grape berry moth, Paralobesia viteana, using reduced-risk insecticides, cultural controls, and conservation of natural enemies

Jenkins, Paul E. January 2006 (has links)
Thesis (M.S.)--Michigan State University. Dept. of Entomology, 2006. / Title from PDF t.p. (viewed on June 19, 2009) Includes bibliographical references (p. 106-117). Also issued in print.
155

Quelques expériences sur l'évaporation de spray dense et la chimiotaxie de la mite / Some experiments on dense spray evaporation and moth chemotaxis

Rivas, Aloïs, de 12 July 2017 (has links)
Ce manuscrit présente des études expérimentales sur l'évaporation de gouttes et la chimiotaxie de la mite.Une première partie s'intéresse à l'évaporation de spray dense au moyen d'une nouvelle approche, par analogie avec le mélange scalaire. Dans cette limite de forte densité en gouttes, où il y a saturation en vapeur au sein des structures constituantes, l'évaporation est principalement fonction de l'étirement auxquelles ces structures sont soumises. C'est en effet celui-ci qui conditionne le taux d'évacuation de cette vapeur interstitielle, ce qui permet de mettre les gouttes en contact avec un environnement plus sec, déclenchant ainsi leurs évaporations.Une deuxième partie s'intéresse à une application de la compréhension de cette dynamique d'évaporation de spray dense à un contexte d'entomologie: la chimiotaxie de la mite. Il s'agit du processus par lequel l'animal va se repérer dans un champ de concentration, pour localiser la source d'une substance attractive par exemple (ici de la phéromone sexuelle). Cette partie a tendu vers l'obtention d'une visualisation conjointe de la trajectoire de l'animal et du champ de concentration sous-jacent par la visualisation des gouttes. / This thesis present some experiments on droplets evaporation and moth chemotaxis.In a first part, dense spray evaporation is explained through a new approach, drawing an analogy with scalar mixing. In this high density droplets limit, where vapor saturation is reached within the structures, evaporation is mainly controlled by the intensity at which these structures are stretch. It is indeed the stretching that controls the rate at witch interstitial vapor is evacuated: droplets are thus in contact with a dryer environment, so they can start to evaporate.A second part take an interest in applying dense spray evaporation dynamic understanding to an entomologist situation: moth chemotaxis. This is the process by which animals find their way in a concentration field, such at finding a chemoattractant source for instance (sexual pheromone in our case). This part tended towards visualizing animal trajectory and concentration field underlying through droplets visualization simultaneously.
156

Izolace, charakterizace a lokalizace ortologní sekvence genu \kur{Notch} u obaleče jablečného, \kur{Cydia pomonella} / Isolation, characterization and localization of orthologous sequence of the \kur{Drosophila Notch} gene in codling moth, \kur{Cydia pomonella}

KŮTA, Václav January 2011 (has links)
The codling moth, Cydia pomonella (Tortricidae) is a significant pest in apple orchards. In the 1990ies, a control programme using the Sterile Insect Technique (SIT) has been established, based on bisexual releases of sterile insects into wild populations of this pest. Male-only releases are not possible due to the lack of an efficient system to produce male-only progeny. Recently, a new approach has been proposed for the development of genetic sexing strains in Lepidoptera. It is based on insertion of a dominant conditional lethal mutation of the Notch gene, derived from the N60g11 allele of Drosophila, into the female W chromosome by means of transgenesis. This study deals with isolation, characterization, and chromosomal localization of a codling moth orthologue of the Drosophila Notch gene with the aim to prepare a mutant sequence of the orthologue to be used in plasmid constructs for germline transformation of this pest.
157

Expressão gênica em resposta ao dano causado por Plutella xylostella (L., 1758) em plantas de repolho inoculadas com Kluyvera ascorbata /

Crialesi, Paula Cristina Brunini. January 2009 (has links)
Resumo: A traça-das-crucíferas (Plutella xylostella) é uma praga que ataca culturas de brássicas, causando enormes prejuízos econômicos aos agricultores. O aparecimento de populações resistentes a inseticidas tem dificultado seu manejo, fazendo-se necessário a busca por alternativas de controle que viabilizem a economia do custo de produção, preservando o ambiente de inseticidas químicos em altas doses. As plantas possuem um mecanismo constitutivo de resistência que atua na sua defesa frente às diferentes adversidades bióticas e abióticas, o que representa altos gastos metabólicos. O mecanismo de resistência pode ser melhorado com a indução de resistência por um ou mais elicitores, como é o caso das bactérias promotoras de crescimento. O objetivo deste estudo foi detectar sequências gênicas expressas em resposta à indução de resistência de repolho à traça das crucíferas. A bactéria utilizada como indutora das respostas de defesa foi a Kluyvera ascorbata devido à ação já descrita anteriormente com repolho e traça-das-cruciferas, onde ficou evidente sua influência na defesa contra essa praga. Por meio do sequenciamento de cDNA foi possível identificar uma significativa alteração no metabolismo de plantas que abrigavam esta bactéria, suprimindo da ação de muitos genes, durante o processo de defesa da planta contra o estresse causado pela injúria de lagartas de P. xylostella / Abstract: The diamondback moth Plutella xylostella is a pest that attacks brassics causing great economic losses to the growers. The rise of resistant populations to the chemical insecticides imposes difficulties on this pest management, so the search of other ways to overcame this situation became quite relevant so as to help to reduce production costs and at the same time avoiding the use of high dosage of the commonly used pesticides. Plants exhibit a constitutive resistance mechanism that acts favoring their defense towards biotic and abiotic stress situations, which involves high metabolic energetic challenges. The defense mechanisms may be improved with the induction of resistance by a number of different elicitors, such as the use of plant growth promoting bacteria. The aim of the present work was to detect plant gene sequences in response to cabbage resistance induction against the diamondback moth. Kluyvera ascorbata was used to induce the plant's growth promotion elicitor due to previously described influence. Analyzing DNA sequencing procedures from cDNA library samples, it was possible to observe drastic differences on the plants metabolism when such bacteria was used, either by suppressing the action of several genes while the plant's defense mechanisms was in action against injuries caused by P. xylostella larvae / Orientador: Manoel Victor Franco Lemos / Coorientador: Robson Thomaz Thuler / Banca: Janete Apparecida Desidério Sena / Banca: João Roberto Spotti Lopes / Mestre
158

Temperatura como parâmetro para armazenamento de Plutella xylostella (L., 1758) (Lepidoptera: Plutellidae) em criação de laboratório

Otuka, Alessandra Karina [UNESP] 19 May 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-05-19Bitstream added on 2014-06-13T18:53:11Z : No. of bitstreams: 1 otuka_ak_me_jabo.pdf: 1152577 bytes, checksum: 8e07d08c9d9ef5d2ba47566363186697 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O trabalho foi desenvolvido no Laboratório de Biologia e Criação de Insetos (LBCI) da FCAV-Unesp, para avaliar a influência de diferentes temperaturas e períodos de exposição no desenvolvimento de Plutella xylostella, para viabilizar o armazenamento de ovos, lagartas e pupas e facilitar o manejo da criação em laboratório. Avaliou-se a biologia de P. xylostella armazenando ovos e lagartas nas temperaturas de 3, 5, 8, 10, 12, 16, 20 e 24°C por 0, 5, 10, 15, 20, 25 e 30 dias de exposição, sendo “0” a testemunha, mantida em 25±1°C, 70±10% UR e 12 horas de fotofase. Avaliou-se também a biologia de P. xylostella armazenando pupas nas temperaturas de 3, 5 e 8°C por 0, 5, 10, 15, 20, 25 e 30 dias de exposição. O armazenamento de ovos e pupas de P. xylostella pode ser realizado por até 15 dias a 8ºC sem que ocorram perdas consideráveis nas suas características biológicas. O armazenamento de lagartas de 1° ínstar de P. xylostella pode ser realizado até 10 dias a 20ºC, já as de 2° ínstar podem ser armazenadas por até 15 dias a 16ºC, as de 3º ínstar por até 20 dias a 20ºC e as de 4º ínstar por até 5 dias a 20ºC, acima desses períodos e abaixo dessas temperaturas ocorrem reduções significativas no número de ovos colocados por fêmea / The work was conducted in the Laboratory of Insect Biology and Rearing (LBCI), FCAV-Unesp, to evaluate the influence of different temperatures and exposure periods on development of Plutella xylostella, trying to enable the storage of eggs, larvae and pupae to facilitate the management of laboratory rearing. For this, we evaluated the biology of P. xylostella larvae and storing eggs at temperatures of 3, 5, 8, 10, 12, 16, 20 and 24°C for 0, 5, 10, 15, 20, 25 and 30 days of exposure, and 0 the check, maintained at 25±1°C, 70±10% RH and 12 hours photophase. We also evaluated the biology of P. xylostella storing pupae at temperatures of 3, 5 and 8°C for 0, 5, 10, 15, 20, 25 and 30 days of exposure. The storage of eggs and pupae of P. xylostella can be done 15 days at 8°C without significant losses that occur in biological characteristics. The storage of a larval first instar of P. xylostella can be performed up to 10 days at 20°C, already the second instar can be stored for 15 days at 16°C, third instar for up to 20 days at 20°C and fourth instar for 5 days at 20°C, above this periods and below these temperatures are reduced significantly the number of eggs per female
159

Expressão gênica em resposta ao dano causado por Plutella xylostella (L., 1758) em plantas de repolho inoculadas com Kluyvera ascorbata

Crialesi, Paula Cristina Brunini [UNESP] 25 September 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-09-25Bitstream added on 2014-06-13T19:54:05Z : No. of bitstreams: 1 crialesi_pcb_me_jabo.pdf: 717305 bytes, checksum: ddf9d322f3798935db316f769791eac7 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A traça-das-crucíferas (Plutella xylostella) é uma praga que ataca culturas de brássicas, causando enormes prejuízos econômicos aos agricultores. O aparecimento de populações resistentes a inseticidas tem dificultado seu manejo, fazendo-se necessário a busca por alternativas de controle que viabilizem a economia do custo de produção, preservando o ambiente de inseticidas químicos em altas doses. As plantas possuem um mecanismo constitutivo de resistência que atua na sua defesa frente às diferentes adversidades bióticas e abióticas, o que representa altos gastos metabólicos. O mecanismo de resistência pode ser melhorado com a indução de resistência por um ou mais elicitores, como é o caso das bactérias promotoras de crescimento. O objetivo deste estudo foi detectar sequências gênicas expressas em resposta à indução de resistência de repolho à traça das crucíferas. A bactéria utilizada como indutora das respostas de defesa foi a Kluyvera ascorbata devido à ação já descrita anteriormente com repolho e traça-das-cruciferas, onde ficou evidente sua influência na defesa contra essa praga. Por meio do sequenciamento de cDNA foi possível identificar uma significativa alteração no metabolismo de plantas que abrigavam esta bactéria, suprimindo da ação de muitos genes, durante o processo de defesa da planta contra o estresse causado pela injúria de lagartas de P. xylostella / The diamondback moth Plutella xylostella is a pest that attacks brassics causing great economic losses to the growers. The rise of resistant populations to the chemical insecticides imposes difficulties on this pest management, so the search of other ways to overcame this situation became quite relevant so as to help to reduce production costs and at the same time avoiding the use of high dosage of the commonly used pesticides. Plants exhibit a constitutive resistance mechanism that acts favoring their defense towards biotic and abiotic stress situations, which involves high metabolic energetic challenges. The defense mechanisms may be improved with the induction of resistance by a number of different elicitors, such as the use of plant growth promoting bacteria. The aim of the present work was to detect plant gene sequences in response to cabbage resistance induction against the diamondback moth. Kluyvera ascorbata was used to induce the plant’s growth promotion elicitor due to previously described influence. Analyzing DNA sequencing procedures from cDNA library samples, it was possible to observe drastic differences on the plants metabolism when such bacteria was used, either by suppressing the action of several genes while the plant’s defense mechanisms was in action against injuries caused by P. xylostella larvae
160

Influência de gerações de Plutella xylostella (L.) (Lepidoptera: Plutellidae) e de radiação no desempenho de isolados de Bacillus thuringiensis Berliner

Viana, Cácia Leila Tigre Pereira [UNESP] 16 December 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-12-16Bitstream added on 2014-06-13T20:42:38Z : No. of bitstreams: 1 viana_cltp_dr_jabo.pdf: 3925525 bytes, checksum: 481305986effd42e171c9be8a7117ddf (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O trabalho foi desenvolvido no Laboratório de Biologia e Criação de Insetos (LBCI) da FCAV - Unesp com objetivo geral de estudar influência de gerações de Plutella xylostella (L.) (Lepidoptera: Plutellidae) e de radiação no desempenho de isolados de Bacillus thuringiensis Berliner. A linhagem e os isolados foram provenientes do estoque do Laboratório de Biologia de Bactéria e Biotecnologia Aplicada da FCAV - Unesp. A concentração de esporo-cristal para iniciar a metodologia de pressão de seleção foi determinada pela análise de probit, sendo o valor de 6x106 esporos/mL. Esta população foi submetida a bioensaios com diferentes concentrações da linhagem HD-1, do isolado T08.024 e do produto comercial Agree® (Bacillus thuringiensis var. aizawai e proteína cristal de B. thuringiensis var. kurstaki) em várias gerações da seleção. Paralelamente, avaliou-se a suscetibilidade de lagartas de P. xylostella da criação mantida no LBCI a diferentes isolados patogênicos e com potencial de virulência. Também se realizou um estudo sobre ação da radiação ultravioleta na patogenicidade do isolado T08.024 por diferentes intervalos de exposição a radiação em laboratório e em campo. A metodologia de pressão de seleção foi estabelecida a partir da oitava geração onde se obteve mais que 50% de sobrevivência. Da geração 8 em diante passou-se a pulverizar concentrações mais altas desta linhagem, de acordo com o padrão de mortalidade apresentado em cada bioensaio na geração anterior. A viabilidade larval foi significativamente influenciada pelos tratamentos dentro das gerações. Entre gerações houve redução na mortalidade para o tratamento HD-1 na concentração de 3x108 esporos/mL. O padrão de suscetibilidade da criação estoque do LBCI foi alto (100% de mortalidade) para todas as concentrações testadas... / This work was conducted at the Laboratório de Biologia e Criação de Insetos (LBCI) of FCAV - Unesp (LBCI), with the general objective of studying the influence of generations of Plutella xylostella (L.) (Lepidoptera: Plutellidae) and the radiation performance of Bacillus thuringiensis Berliner. The strain and the isolates were from the Laboratório de Biologia de Bactéria e Biotecnologia Aplicada da FCAV-Unesp stock. The concentration of sporecrystal to the method of selection pressure was determined by probit analysis, and the value used was 6x106 spores / mL. This population was subjected to bioassays using different concentrations of HD-1 strain, Agree® and of T08.024 strain on several generations of selection. In parallel, it was evaluated the susceptibility of larvae of P. xylostella maintained in the LBCI different to pathogenic isolates and virulence potential. Also it was conducted a study in verify he action of ultraviolet radiation on the isolate T08.024 pathogenicity for different intervals of exposure to radiation in laboratory and field. The methodology of selection pressure was established from the eight generation where was obtained more than 50% of survival. From generation eight began the spray higher concentrations of HD-1 strain, according to the standard mortality presented in each test in the previous generation. The larval survival was significantly influenced by treatments within the generations. Between generations, mortality has been reduced to the HD-1 treatment at a concentration of 3x108 spores / mL. The susceptibility of LBCI standard population was high (100% mortality) for all concentrations tested to the eight strains. Ultraviolet radiation did not affect the pathogenicity of the T08.024 strain.

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