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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.
181

[en] (DES)CONSTRUCTIONS OF THE INVISIBILIZATION OF REFUGEES IN RIO DE JANEIRO: AN APPROACH ON CULTURAL INTEGRATION / [pt] (DES)CONSTRUÇÕES DA INVISIBILIZAÇÃO DOS REFUGIADOS NO RIO DE JANEIRO: UMA ABORDAGEM ACERCA DA INTEGRAÇÃO CULTURAL

LETICIA CRISTINA PEREIRA DE CASTRO 17 April 2020 (has links)
[pt] Das últimas décadas para os dias atuais, o fluxo de refugiados vindo para o Brasil vem aumentando cada vez mais. Preocupados com a inserção dos refugiados dentro da cidade, o governo, as instituições e a sociedade civil trabalham para integrar esse grupo de pessoas. Apesar de existirem diversas formas de integração, a maneira mais visada desde então é a integração econômica, ou seja, a obtenção de um emprego no país de acolhida e consequente empoderamento econômico do(a) refugiado(a). Assim, outras formas de integração tão importantes quanto esta acabam por ficar esquecidas. Este trabalho, com o intuito de contribuir para o debate de políticas públicas voltadas para a integração dos imigrantes forçados, parte da premissa que a desatenção às políticas culturais ligadas à integração dos refugiados no Rio de Janeiro se relacionam às dificuldades de pertencimento e visibilidade dentro da cidade. Em primeiro lugar, é discutido a importância desse debate nos dias atuais, seguido de uma revisão bibliográfica que discute processos de integração e a importância da cultura nesse cenário. Em segundo lugar, o relatório traz, dentro do seu estudo de caso, um olhar mais aprofundado sobre o deslocamento dos congoleses diante desse quadro e como o ensino da língua portuguesa é peça-chave na integração cultural. Por fim, são feitas algumas recomendações, dando ênfase na preponderância da atuação dos atores governamentais, a fim de que o processo integratório seja feito de maneira mais humana. / [en] From the last decades to the present day, the flow of refugees to Brazil has been increasing. Concerned about the inclusion of refugees within the city, government, institutions and civil society are working to integrate this group of people. Although there are various forms of integration, the most targeted approach since then is economic integration, ie obtaining employment in the host country and consequent economic empowerment of the refugee. Thus, other forms of integration as important as this are eventually forgotten. This work, with the aim of contributing to the debate of public policies aimed at the integration of forced immigrants, starts from the premise that the lack of attention to the cultural policies related to the integration of refugees in Rio de Janeiro are connected to the difficulties of belonging and visibility within the city. Within this work, firstly, the importance of this debate in the present day is discussed, followed by a bibliographical review that discusses integration processes and the importance of culture in this scenario. Secondly, the report brings, in its case study, a more indepth look at the displacement of Congolese in this context and how the teaching of the Portuguese language is a key element in cultural integration. Finally, some recommendations are made, emphasizing the preponderance of the performance of governmental actors, so that the integration process is done in a more humaneway.
182

[pt] VENEZUELANOS/AS NO BRASIL: ACOLHIMENTO E CONTROLE – FACES DA POLÍTICA DE PROTEÇÃO AOS REFUGIADOS / [en] VENEZUELANS IN BRAZIL: RECEPTION AND CONTROL – FACETS OF REFUGEE PROTECTION POLICY

ANA GABRIELA DE PAIVA GONCALVES 04 August 2022 (has links)
[pt] Esta dissertação de mestrado resulta de uma pesquisa documental e bibliográfica realizada durante a pandemia mundial ocasionada pela COVID-19 (2020-2022). O objetivo deste trabalho foi analisar qualitativamente os direcionamentos dados pelas políticas migratórias brasileiras durante a pandemia e suas repercussões ao grupo de nacionalidade venezuelana, visto ser este o maior fluxo migratório para o Brasil neste período. Utilizamos a análise documental como ferramenta metodológica, que possibilitou a reunião de documentos jurídiconormativos relacionados ao acolhimento humanitário da migração venezuelana pelo Estado brasileiro no período de 2018 a 2021 e após um panorama geral do material produzido pelos órgãos federais, selecionamos os documentos a serem analisados no contexto da pandemia. Os países do Sul-Global têm sido as principais rotas da migração de cidadãos venezuelanos e o que podemos observar a respeito das políticas migratórias implementadas, é que as formas de concebê-las e executá-las são muito diversificadas e estão vinculadas ao processo de formação regional, e de aspectos sociais, políticos e econômicos de cada país, apesar dos tratados internacionais de proteção humanitária e de refúgio. No caso brasileiro, a recepção de migrantes venezuelanos é atravessada pela militarização e ordenamento das fronteiras e por práticas precárias de acolhimento, muito embora, haja uma mudança de paradigma no arcabouço jurídico que caminha em direção a consolidação do Brasil com uma legislação mais democrática e protetiva em relação as migrações internacionais. Durante a pandemia percebe-se uma inflexão na recepção aos migrantes a partir do fechamento das fronteiras territoriais por sucessivas portarias interministeriais sob o pretexto de prevenção epidemiológica. Diante dos retrocessos na garantia dos direitos, observou-se que o desenho da política migratória na atualidade ainda é fragmentado e contraditório, com desafios e problemáticas que não garantem ao migrante e/ou refugiado o acesso universal ao sistema de proteção social brasileiro, além da ausência de implementação de políticas públicas intersetoriais nas três esferas governamentais que acolham os migrantes a partir das suas especificidades, vulnerabilidades, demandas, desejos e modos de vida / [en] This master s thesis is the result of a documentary and bibliographic research conducted during the global pandemic caused by COVID-19 (2020-2022). The objective of this work was to qualitatively analyze the directions given by Brazilian migration policies during the pandemic and its repercussions on the Venezuelan nationality group, since this is the largest migratory flow to Brazil in this period. We used documentary analysis as a methodological tool, which enabled the gathering of legal- normative documents related to the humanitarian reception of Venezuelan migration by the Brazilian State in the period from 2018 to 2021 and after an overview of the material produced by federal agencies, we selected the documents to be analyzed in the context of the pandemic. The countries of the Global-South have been the main routes of migration of Venezuelan citizens and what we can observe regarding the implemented migration policies, is that the ways of conceiving and executing them are very diverse and are linked to the process of regional formation, and social, political and economic aspects of each country, despite international humanitarian protection and refugee treaties. In the Brazilian case, the reception of Venezuelan migrants is crossed by the militarization and regulation of the borders and by precarious practices of reception, even though there is a change of paradigm in the legal framework that moves towards the consolidation of Brazil with a more democratic and protective legislation in relation to international migration. During the pandemic, we can see an inflexion in the reception of migrants as of the closing of territorial borders by successive interministerial ordinances under the pretext of epidemiological prevention. Given the setbacks in the guarantee of rights, it was observed that the design of migration policy today is still fragmented and contradictory, with challenges and problems that do not guarantee the migrant and/or refugee universal access to the Brazilian social protection system. The lack of implementation of intersectoral public policies in the three spheres of government that welcome migrants based on their specificities, vulnerabilities, demands, desires and ways of life.
183

[en] ASYLUM AND EPISTEMIC INJUSTICE IN BRAZIL / [pt] REFÚGIO E INJUSTIÇA EPISTÊMICA: UMA ANÁLISE A PARTIR DO BRASIL

FLAVIA RODRIGUES DE CASTRO 28 May 2020 (has links)
[pt] Esta tese é o resultado de uma pesquisa de inspiração etnográfica sobre o refúgio como prática de injustiça epistêmica, analisado por meio do universo brasileiro da elegibilidade e dos processos de produção de significados sociais. A concepção de injustiça epistêmica está relacionada a duas importantes práticas epistêmicas: produzir e compartilhar o conhecimento com outros por meio do testemunho e fazer sentido das próprias experiências sociais. A tese busca, assim, examinar a produção e a transmissão do conhecimento nos processos burocráticos da elegibilidade, isto é, na determinação do status de refugiado, e as formas de representação midiática em torno da figura do refúgio e seus sujeitos. Para tanto, a análise contou com uma pluralidade metodológica composta por trabalho de campo por meio da realização de entrevistas e abordagem com corpus através do uso de softwares específicos. A partir disso, a tese analisa o espaço das práticas epistêmicas que atravessam a categoria do refugiado e podem contribuir para a produção de injustiças, afetando a vida de solicitantes de refúgio e refugiados no Brasil. / [en] This thesis is the result of a research on asylum as epistemic injustice, analyzed through the Brazilian eligibility process and the practices of media representation in the country. The concept of epistemic injustice is intimately related to two crucial epistemic practices: conveying knowledge to others and making sense of our own social experiences. Hence, the two main aims of the research are the analysis of knowledge production in the bureaucratic process of eligibility (or refugee status determination process, RSD) and the investigation on how the Brazilian mainstream media represents refugees. To this end, the pluralistic research methods used consist of interview-based fieldwork and corpus linguistics with the help of specific software. The thesis therefore analyzes the space of epistemic practices that have an impact on the refugee category and may contribute to the production of injustices, affecting the lives of asylum seekers and refugees in Brazil.
184

[pt] O (DES)ENCONTRO ENTRE O REFÚGIO E O PROBLEMA DA DIFERENÇA NAS RELAÇÕES INTERNACIONAIS: UM MOVIMENTO DESCONSTRUTIVO / [en] THE (DIS)ENCOUNTER BETWEEN REFUGE AND THE PROBLEM OF DIFFERENCE IN INTERNATIONAL RELATIONS: A DECONSTRUCTIVE MOVEMENT

ANDRESSA MACIEL CORREA 26 August 2024 (has links)
[pt] Como compreender as marcas da diferença e suas fronteiras que separam quem faz parte ou não, quem é bem-vindo ou não, e como configuram rastros de divisões de mundo e subjetividades? Como tal diferença foi pensada, quais os enquadramentos foram usados para posicionar diversas populações em deslocamento migratório forçado, produzindo um jogo entre um suposto eu e um suposto outro? É possível (re)pensar o problema da diferença pela chave de inteligibilidade e movimento da desconstrução, da différance? É dentro desta trajetória que pretendo construir e traduzir tal percurso de (des)encontros com a temática, a partir de uma escrita que se esforça a não recalcar as aporias, e faz uso deste recenseamento dos próprios encontros e desencontros que precipitam as seguintes reflexões, no esforço de contribuir para os estudos sobre migração e refúgio, seja dentro ou fora do campo de saber das Relações Internacionais. Em outros termos, é um movimento possível de prestar atenção às linhas de demarcação (sejam geográficas, dialéticas, coloniais, raciais, dentre outras), fraturas e seus territórios indesignáveis das experiências vividas, como uma maneira de fazer ecoar a dimensão do (des)encontro com o contexto do refúgio, e encontrar-se diante de si mesmo, o risco, a responsabilidade de decompor em miríades de partículas tal viagem (sem pretensões de dar conta desta) a ser empreendida quando se fala, estuda e trabalha no cenário do refúgio. As linhas deste trabalho propõem destacar a dimensão relacional da pesquisa, principalmente nos encontros e desencontros com o contexto do refúgio – e (re)considerar tais subjetividades viandantes em situação de refúgio, não como substâncias a serem capturadas, mas como formas radicais de relacionalidade, que são sempre ao mesmo tempo singular e plural, irredutíveis a uma entidade pressuposta a um encontro e desencontro totalizantes –, e como (re)olhar esta relação a partir de uma constatação pelo movimento da desconstrução desse (des)encontro constitutivo e ético. / [en] How can we understand the marks of difference and the borders that separate who belongs and who doesn t, who is welcome and who isn t, and how they create traces of world dividions and subjectivities? How has this difference been thought of, what frameworks have been used to position various populations in forced migratory displacement, producing a game between a supposed self and a supposed Other? Is it possible to (re)think the problem of difference through the key of intelligibility and movement of deconstruction, of différance? It is within this trajectory and that I intend to construct and translate such a journey of (dis)encounters with the theme from a criting that strives not to repress the aporias and makes use of this census of the very encounters and disagreements that precipitate the following reflections in an effort to contribute to studies on migration and refuge, whether inside or outside the field of knowledge of International Relations. In other words, it is possible move to pay attention to the lines of demarcation, fractures and their undesignable territoriesof lived experiences, as a way of echoing the dimension of the (dis)encounter with the context of refuge, and finding oneself a journey (without pretending to be able to account for it) to be undertaken when talking about, studing and working in the refuge scenario. The lines (whether geographical, dialectical, colonial, racial, among others), of this work lead to and propose some attempts to grasp these facets based on a movement and language of crossing and opening up to diffrent logics, scenarios and theoretical frameworks of contact, not only within the field of International Relations. It s a dialogue that brings together horizons of possibility for thinking about the context of refuge and its borders, demarcations, possibilities, impossibilities and negotiations present in the relationship with difference itself. The lines of this work propose to highlight the relational dimension of research, especially in the encounters and disencounters with the context of refuge – and to (re)consider these subjectivities in displacement, not as substances to be captured, but as radical forms of relationality, which is always at the same time singular and plural, irreducible to an entity presupposed by a totalizing encounter and disagreement – and how to (re)look at this relationship from a point of view of the movement of deconstruciton of this constitutive and ethical (dis)encounter.
185

Effectiveness of varied refugia configurations for the genetically modified maize (Zea mays L.) in Kwa-Zulu-Natal midlands

Moodley, Odeshnee 11 1900 (has links)
Genetically modified (GM) white and yellow maize, Zea mays, has been commercially released and cultivated in South Africa since 1997/1998. The traits expressed are insect resistance and herbicide tolerance conferred by the bacteria Bacillus thuringiensis (Bt) Cry genes and Agrobacterium 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase gene, respectively. The Cry genes have been used widely to control lepidopteran insect pests but insect resistance to GM Bt crops has been a concern since the introduction of this technology. A management strategy includes refugia planting of 5% non-Bt plants, with no insecticide application, and 20%, where insecticide application is allowed. These refugia are designed to allow the survival of insect pests within restricted planted zones. However, in South Africa there are reports of Bt-resistant stem borer (Busseola fusca) (Fuller) (Lepidoptera: Noctuidae) and non-compliance with refuge planting. The aims of this study were two-fold: 1. To conduct a survey among KwaZulu-Natal (KZN) GM maize growers to ascertain information such as level of compliance with refuge planting and to determine which refugia were predominantly planted and reasons thereof; 2. To conduct a replicated field trial to determine yield, insect borer damage and economic benefit of the 5% unsprayed and 20% sprayed refuge options (including three configurations namely strip, perimeter and block and a 5 and 20% ‘refuge-in-a-bag’ option). The survey indicated that 28 out of 29 (96.6%) KZN Bt maize growers plant the 5% non-sprayed refuge with 27 (96.4%) of those respondents planting the strip configuration for the purpose of insect management (75%) and ease of planting (32.2%). The survey also showed that 7 (seven) i.e. 21.9% of KZN Bt maize growers observed borer damage and although growers are now fully compliant with refugia planting requirements, initially 7 respondents (24.1%) did not comply with or plant refugia correctly. Furthermore, 7 respondents reported insect borer damage in their maize with 4 of the 7 instances (57.1%) likely stemming from incorrectly planted refugia. vii No significant differences in yield or insect damage were observed between the 5 and 20% refugia for any of the planting configurations in the field trial. However due to costs involved with insecticide application and labour required for the operation in the 20% option, these treatments were less economically advantageous than the non-Bt control. The 20% block and strip configurations had a cost benefit ratio of ZAR 7.21 and ZAR 6.67 respectively, earned per R1 spent by the grower compared with ZAR 7.76 in the sprayed control. The cost-benefit comparison for the 5% block and strip configurations was ZAR 8.48 and ZAR 7.71, respectively compared with ZAR 9.44 in the unsprayed control. In addition, the 20% seed mixture limited borer damage to 4.95% when compared with 15.77% damage in the sprayed control (ANOVA, F pr = 0.124). The seed mixtures are not available commercially and the results from the survey indicated that some education and marketing by the seed companies would be advisable prior to their release to the farming community. In order to determine which of the refuge options between 5 and 20% would be more advantageous for growers overall, regardless of the planting configuration; data were grouped and analysed. There were no significant differences in either the yield or insect damage for the 5 and 20% refugia, but the cost-benefit calculations indicated that the 5% option was more cost effective – for the 5 and 20% refugia, ZAR 7.97 and ZAR 7.15 respectively, earned per ZAR 1 spent by the grower (ANOVA, F pr. = 0.03). This is because no insecticide was used in the 5% treatments. Mean ear damage comparisons between the 5 and 20% refugia showed that the 20% refuge in the perimeter configuration incurred the least damage (2.65% ear damage) compared with 5% perimeter (10.86% ear damage), although the reasons for this are not clear. While the results of the field trials showed no significant differences in insect damage and yield with regard to choice of refuge configuration, monitoring insect resistance management remains an integral part of Bt maize crops in South Africa, in order to delay further resistance development and to prolong the viability of Bt technology. / Agriculture and  Animal Health / M. Sc. (Agriculture)
186

Predicting leatherback sea turtle sex ratios using spatial interpolation of nesting beach temperatures

Unknown Date (has links)
Sex determination in leatherback sea turtles is directed primarily by the temperatures a clutch experiences during the middle third of development. Warmer temperatures tend to produce females will cooler temperatures yield males. Nest temperatures can vary spatially and temporally. During the 2010 and 2011 nesting seasons, this study estimated the hatchling sex ratio of leatherback sea turtles on Sandy Point National Wildlife Refuge (SPNWR), St. Croix, U.S. Virgin Islands. I measured sand temperatures from May- August and across the spatial range of leatherback nesting habitat. I spatially interpolated those temperatures to create maps that predicted temperatures for all nests incubating on SPWNR. Nest temperatures were also directly measured and compared with predicted nest temperatures to validate the prediction model. Sexes of dead-in-nest hatchlings and full term embryos were used to confirm the sex-temperature response. The model showed that microclimatic variation likely impacts the production of both sexes on SPNWR. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2013.
187

The distribution of predaceous fire ant species on important sea turtle nesting beaches in St. Croix, U.S. Virgin Islands

Unknown Date (has links)
The tropical fire ant, Solenopsis geminata is a New World species with a wide native range including South America as well as several Caribbean islands. The red imported fire ant, Solenopsis invicta is native to parts of South America. Both species are known for preying on sea turtles’ eggs and hatchlings. The objectives of this thesis research were to conduct follow-up and baseline ant species distribution surveys on four sea turtle nesting beaches in St. Croix, U. S. Virgin Islands. Tuna baits were set out at beaches; specimens were collected, frozen, preserved then identified. Results show that there was a significant change in the fire ants’ distribution at Sandy Point National Wildlife Refuge (SPNWR) while none were found at Jack Bay. Fire ants were also present on the other two baseline surveyed nesting beaches. The displacement of S. geminata by S. invicta was observed at SPNWR, which also was presumed by previous surveys. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
188

Effectiveness of varied refugia configurations for genetically modified maize (Zea mays L.) in KwaZulu-Natal midlands

Moodley, Odeshnee 11 1900 (has links)
Genetically modified (GM) white and yellow maize, Zea mays, has been commercially released and cultivated in South Africa since 1997/1998. The traits expressed are insect resistance and herbicide tolerance conferred by the bacteria Bacillus thuringiensis (Bt) Cry genes and Agrobacterium 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase gene, respectively. The Cry genes have been used widely to control lepidopteran insect pests but insect resistance to GM Bt crops has been a concern since the introduction of this technology. A management strategy includes refugia planting of 5% non-Bt plants, with no insecticide application, and 20%, where insecticide application is allowed. These refugia are designed to allow the survival of insect pests within restricted planted zones. However, in South Africa there are reports of Bt-resistant stem borer (Busseola fusca) (Fuller) (Lepidoptera: Noctuidae) and non-compliance with refuge planting. The aims of this study were two-fold: 1. To conduct a survey among KwaZulu-Natal (KZN) GM maize growers to ascertain information such as level of compliance with refuge planting and to determine which refugia were predominantly planted and reasons thereof; 2. To conduct a replicated field trial to determine yield, insect borer damage and economic benefit of the 5% unsprayed and 20% sprayed refuge options (including three configurations namely strip, perimeter and block and a 5 and 20% ‘refuge-in-a-bag’ option). The survey indicated that 28 out of 29 (96.6%) KZN Bt maize growers plant the 5% non-sprayed refuge with 27 (96.4%) of those respondents planting the strip configuration for the purpose of insect management (75%) and ease of planting (32.2%). The survey also showed that 7 (seven) i.e. 21.9% of KZN Bt maize growers observed borer damage and although growers are now fully compliant with refugia planting requirements, initially 7 respondents (24.1%) did not comply with or plant refugia correctly. Furthermore, 7 respondents reported insect borer damage in their maize with 4 of the 7 instances (57.1%) likely stemming from incorrectly planted refugia. vii No significant differences in yield or insect damage were observed between the 5 and 20% refugia for any of the planting configurations in the field trial. However due to costs involved with insecticide application and labour required for the operation in the 20% option, these treatments were less economically advantageous than the non-Bt control. The 20% block and strip configurations had a cost benefit ratio of ZAR 7.21 and ZAR 6.67 respectively, earned per R1 spent by the grower compared with ZAR 7.76 in the sprayed control. The cost-benefit comparison for the 5% block and strip configurations was ZAR 8.48 and ZAR 7.71, respectively compared with ZAR 9.44 in the unsprayed control. In addition, the 20% seed mixture limited borer damage to 4.95% when compared with 15.77% damage in the sprayed control (ANOVA, F pr = 0.124). The seed mixtures are not available commercially and the results from the survey indicated that some education and marketing by the seed companies would be advisable prior to their release to the farming community. In order to determine which of the refuge options between 5 and 20% would be more advantageous for growers overall, regardless of the planting configuration; data were grouped and analysed. There were no significant differences in either the yield or insect damage for the 5 and 20% refugia, but the cost-benefit calculations indicated that the 5% option was more cost effective – for the 5 and 20% refugia, ZAR 7.97 and ZAR 7.15 respectively, earned per ZAR 1 spent by the grower (ANOVA, F pr. = 0.03). This is because no insecticide was used in the 5% treatments. Mean ear damage comparisons between the 5 and 20% refugia showed that the 20% refuge in the perimeter configuration incurred the least damage (2.65% ear damage) compared with 5% perimeter (10.86% ear damage), although the reasons for this are not clear. While the results of the field trials showed no significant differences in insect damage and yield with regard to choice of refuge configuration, monitoring insect resistance management remains an integral part of Bt maize crops in South Africa, in order to delay further resistance development and to prolong the viability of Bt technology. / Agriculture and  Animal Health / M. Sc. (Agriculture)
189

Hurricane Storm Surge Sedimentation on the McFaddin National Wildlife Refuge, Texas: Implications for Coastal Marsh Aggradation

Hodge, Joshua B. 05 1900 (has links)
This study uses the storm surge sediment beds deposited by Hurricanes Audrey (1957), Carla (1961), Rita (2005) and Ike (2008) to investigate spatial and temporal changes in sedimentation rates on the McFaddin National Wildlife Refuge in Southeast Texas. Fourteen sediment cores were collected along a transect extending from 90 to 1230 meters inland from the Gulf Coast. Storm-surge-deposited sediment beds were identified by texture, organic content, carbonate content, the presence of marine microfossils, and Cesium-137 dating. The hurricane-derived sediment beds are marker horizons that facilitate assessment of marsh sedimentation rates from nearshore to inland locations as well as over decadal to annual timescales. Near the shore, on a Hurricane Ike washover fan, where hurricane-derived sedimentation has increased elevation by up to 0.68 m since 2005, there was no measurable marsh sedimentation in the period 2008-2014. Farther inland, at lower elevations, sedimentation for the period 2008-2014 averaged 0.36 cm per year. The reduction in sedimentation in the period 2008-2014 on the nearshore part of the marsh is likely due to reduced flooding in response to increased elevation from hurricane storm surge sediment deposition. These results provide valuable knowledge about the sedimentary response of coastal marshes subject to storm surge deposition and useful guidance to public policy aimed at combating the effects of sea level rise on coastal marshes along the Gulf of Mexico.
190

Migration patterns and survival of Busseola fusca larvae in maize plantings with different ratios of Bt and non-Bt seed / Jaco Marais

Marais, Jaco January 2014 (has links)
The high-dose/refuge strategy is used globally to manage insect resistance development in genetically modified crops with insecticidal properties (Bt crops). The “refuge in a bag” (RIB) strategy is also being considered for deployment against several pest species. Busseola fusca, the target pest of Bt maize in South Africa, evolved resistance to Cry1Ab proteins. The objective of this study was to determine whether migrating B. fusca larvae are effectively controlled using the RIB strategy. A field study with a single-gene event (Cry1Ab) and a “pyramid” event (Cry1A.105 + Cry2Ab2) was conducted in which the migration patterns of B. fusca larvae in plots with different seed mixture treatments were studied. The experiment consisted of five seed mixture ratios (5%, 10%, 15%, 20% non-Bt seed and 100 % non-Bt seed as control). Natural infestation was augmented by artificial inoculation with neonate larvae into the central non-Bt maize plant of each plot. Rate of larval survival and migration, measured in terms of increase in number of plants per plot that exhibited borer damage was recorded at weekly intervals until flowering. A laboratory study was conducted to determine larval growth and survival when simulating migration between Bt and non-Bt maize plants. A feeding experiment in which larvae were reared on different types of maize (Bt and non-Bt) was conducted and larval survival and mass recorded after a 7-day feeding period. The incidence of damaged ears, stem damage and damaged internodes per stem were recorded and relationships between these variables determined by means of correlation analyses. A review was conducted in order to identify and discuss similarities and differences between the high-dose/refuge and seed mixture strategies. This was done to determine which strategy would be the most appropriate insect resistance management (IRM) strategy against B. fusca. The rate of survival and migration of B. fusca larvae was significantly higher in the plots with maize expressing Cry1Ab and control plots, than in plots with the pyramid Bt event. Older larvae exhibited improved growth and survival in the laboratory experiment when they were transferred from non-Bt to Bt plants. Positive correlations were found between early and late season damage, although some weaker than others. Plants of the “pyramid event” suffered less late-season damage than those of the single-gene event. Since the increase in number of damaged maize plants over time is associated with migration of older and larger larvae, the observed tendencies may indicate that the assumed high-dose does not kill larvae above a certain developmental stage. The high-dose refuge strategy seems to be the better option for delaying resistance development. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2014

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