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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

Genetic Engineering of Lactobacillus casei for Surface Displaying the Green Fluorescent Protein: An Effort towards Monitoring the Survival and Fate of Probiotic Bacteria in the Gastrointestinal Tract Environment

Chan, Colin H. L. 28 February 2014 (has links)
With the introduction of antibiotics in animal feed becoming less popular, the agricultural industry has begun a shift towards the use of probiotics in animal feed. Since there is no current method to evaluate the risks of using genetically modified probiotics in animal feed. The goal of this project was to create a genetically modified model organism for risk assessment. The genetic marker for that was chosen was GFP that was to be expressed on the surface of the cell. The fluorescent properties allow for visualisation of the genetically modified bacteria and the surface expression would allow for the easy capture and recovery of the bacteria for culturing and cell counts. Genome wide screens were performed using the CW PRED algorithm to locate proteins with LPXTG motif for cell wall anchoring. 16 hypothetical proteins were detected and 6 were selected as candidates for possible surface display of GFP. Of these candidates, the novel L. casei protein LSEI_2320 was found to be expressed at the mRNA during early growth by RT PCR and at then protein level during stationary phase with western blot. This LPXTG protein was found at the surface of L. casei ATCC334 during stationary phase and late stationary phase with immunofluorescence microscopy. A genetically modified L. casei ATCC334 was constructed using the surface protein LSEI_2320 locus as a region for recombination with the pRV300 suicide plasmid. Genetic modification of the locus by the insertion of a GFP reporter region just before the predicted signal peptide site resulted in the abrogation of the expression of LSEI_2320 from the cell surface at the late stationary phase. It appears that this particular gene is not necessary to cell survival even though it is abundantly expressed on the cell surface and can be used as a location for genetic modification in L. casei ATCC334.
182

The international political economy of the Cartagena Protocol on biosafety

Du Plessis, Marthinus Johannes 03 1900 (has links)
Thesis (MA)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: The development of the global biotechnology industry largely coincided with the development of the US biotechnology industry. This resulted in this industry's oligopolistic and centralised nature where only a few multinational chemical and pharmaceutical companies control most biotechnology processes and production of commodities emanating from these processes. The governance of biotechnology has, until recently, been dominated by state actors who have endeavoured to secure national interests, including those of large multinational corporations (MNCs) based within their boundaries. The technological ability of developed states to exploit and use unevenly distributed resources to their advantage means that an uneven relationship exists between these and poor developing countries. This has been highlighted by differences in public opinion about the role and application of biotechnology in society. While some opinions favour the use and application of biotechnology to enhance food supplies and boost production levels and trade, other opinions caution against the possible hazards that genetically manipulated organisms (GMOs) hold for the environment and human existence. The commercialisation of biotechnology has resulted in the exponential growth of genetically manipulated crops in especially the United States and countries like Argentina and Canada. These countries produce large surpluses of staple grains such as corn and soya and try to sell these to countries with food supply problems. The clash in commercial interests stemming from developed countries' insistence on the protection of intellectual property rights (IPR) on genetically manipulated (GM) seeds has caused considerable conflict with poor farmers who will not be able to sustain their livelihoods if they cannot save seeds for future harvests. This is one aspect of the problems surrounding the protection of knowledge products that is exacerbated by the scientific uncertainty pertaining to the risk involved with biotechnology. While some observers agitate for precaution with the use of GMOs, others feel that a lack of scientific proof of harm is sufficient grounds for proceeding with developments in biotechnology. Conversely, there are some that feel that biotechnology is market driven instead of human needs driven, ultimately resulting in developing countries receiving very little benefit from it. The Cartagena Protocol on biosafety was drafted to address some of the difficulties involved with the transboundary movement of GMOs. Although it holds very specific advantages for developing countries, as a regulatory framework it is limited in its scope and application. Developing countries are limited in their policy options to address their need to protect biodiversity and secure their food supply. This means that considerable challenges and constraints await these countries in utilising global governance of public goods and building their human and technological capacities. / AFRIKAANSE OPSOMMING: Die ontwikkeling van die globale biotegnologie-industrie het grootliks saamgeval met die ontwikkeling van die Verenigde State se biotegnologie-industrie. Dit het aanleiding gegee tot hierdie industrie se oligopolistiese en gesentraliseerde aard waar slegs enkele multinasionale chemiese en farmaseutiese maatskappye die meeste biotegnologie prosesse en die vervaardiging van kommoditeite uit daardie prosesse beheer. Die regering van biotegnologie was tot onlangs oorheers deur staatsakteurs wie gepoog het om nasionale belange te beskerm, insluitend die belange van multinasionale korporasies (MNK) wat vanuit hulle grondgebied funksioneer. Die tegnologiese vermoë van ontwikkelde state om oneweredig verspreide hulpbronne tot eie gewin te benut beteken dat 'n ongelyke verhouding bestaan tussen hierdie en arm ontwikkelende state. Dit word beklemtoon deur verskille in openbare mening oor die rol en aanwending van biotegnologie in die samelewing. Terwyl sekere opinies ten gunste van die aanwending van biotegnologie vir die verbetering van voedselbronne en produksievlakke en handel is, dui ander opinies op die moontlike gevare wat geneties gemanipuleerde organismes (GMOs) vir die omgewing en menslike voortbestaan inhou. Die kommersialisering van biotegnologie het gelei tot die eksponensiële groei van geneties gemanipuleerde gewasse in veral die Verenigde State en state soos Argentinië en Kanada. Hierdie state produseer groot hoeveelhede stapelgrane soos mielies en soja en poog om dit te verkoop aan state met voedselvoorsieningsprobleme. Die botsing in kommersiële belange wat spruit uit ontwikkelde state se aandrang op die beskerming van intellektuele eiendomsreg op geneties gemanipuleerde saad veroorsaak beduidende konflik met arm landbouers wie nie hulle lewensonderhoud kan verseker as hulle nie saad kan berg vir toekomstige saaiseisoene nie. Dit is een aspek van die problematiek rondom die beskerming van kennisprodukte wat vererger word deur die wetenskaplike onsekerheid wat gepaard gaan met die risiko's van biotegnologie. Terwyl sekere waarnemers vir waaksaamheid pleit in die gebruik van GMOs, is daar ander wat voel dat 'n gebrek aan wetenskaplike bewyse van skade genoegsame gronde is vir die voortsetting van ontwikkelings in biotegnologie. Insgelyks is daar diegene wat meen dat biotegnologie markgedrewe in plaas van menslike behoefte gedrewe is, wat uiteindelik daartoe lei dat ontwikkelende state baie min voordeel daaruit trek. Die Kartagena Protokoloor bioveiligheid is opgestel om van die probleme betrokke by die oorgrens verskuiwing van GMOs aan te spreek. Hoewel dit spesifieke voordele vir ontikkelende state inhou is dit as reguleringsraamwerk beperk in omvang en aanwending. Ontwikkelende state het beperkte beleidsopsies om hulle behoefte om biodiversiteit te beskerm en voedselvoorsiening te verseker, aan te spreek. Dit beteken dat beduidende uitdagings en beperkings hierdie state in die benutting van globale regering van openbare goedere vir die bou van menslike en tegnologiese kapasiteite in die gesig staar.
183

Food Democracy and The Construction of Risk in The Canadian and U.K. Media

Chénier, Lynn A. 11 December 2009 (has links)
Using a critical discourse analysis (CDA), this thesis examines how risks and food security, in relation to Genetically Modified (GM) foods, are constructed within the media context. The project analyzes news articles that appeared in two Canadian newspapers, The Globe and Mail and The Toronto Star, and two British newspapers, The London Times and the Guardian, during three particular time periods between 1997 and 2005. I evaluate whether or not the selected articles contribute to the public’s understanding of science, and how journalism constructs risk and uncertainty. I also evaluate the use of expert knowledge by journalists. Using the theory of Risk Society, as proposed by sociologist Ulrich Beck, the project explores the connections between political, social, and economic issues connected to globalization. This thesis concludes that journalism in both Canada and Britain does not appear to adequately inform their citizens on matters of food security and the risks of GMOs.
184

Genmat i fokus : analyser av fokusgruppssamtal om genförändrade livsmedel /

Wibeck, Victoria, January 2002 (has links) (PDF)
Diss. Linköping : Univ., 2002.
185

Genetic transformation of the apple rootstock M26 with genes influencing growth properties /

Holefors, Anna, January 1900 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniv. / Härtill 4 uppsatser.
186

Genetic engineering of sugarcane for increased sucrose and consumer acceptance

Conradie, Tobie Tertius 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: Sugarcane is a crop that is farmed commercially due to the high amounts of sucrose that is stored within the mature internodes of the stem. Numerous studies have been done to understand sugar metabolism in this crop as well as to enhance sucrose yields. Until now sugarcane improvement strategies have been implemented through either breeding programs or transgenic manipulation. Public mistrust and regulatory hurdles, however, have made the commercialisation of transgenic crops difficult, expensive and timeconsuming. In this thesis two projects will address issues relating to the above. The first will address an effort to increase sucrose accumulation within the sugarcane culm. This was attempted via the expression of an Arabidopsis thaliana vacuolar pyrophosphatase (AtV-PPase) gene, linked to the maize ubiquitin promoter, in sugarcane callus. It was anticipated that increased activity of the tonoplast-bound AtV-PPase will result in increased sucrose accumulation in the vacuole. Transgenic sugarcane callus lines were tested for soluble sugar content which suggested no significant increase in sucrose content. However, this may change upon further assessment of sugarcane suspension cultures and glasshouse plants. The second project was concerned with the development of a novel sugarcane transformation technology that utilises only sugarcane sequences. This ‘cisgenic’ approach to sugarcane transformation will require a native sugarcane promoter, terminator, vector backbone and selection marker. It was attempted to first isolate a functional promoter as well as developing a selection system based on an endogenous selection marker. A promoter was amplified from sugarcane, using primers designed on a sorghum template, and its expression assessed using a GFP reporter gene. Unfortunately expression could not be confirmed in transgenic sugarcane callus. Currently, an alternative approach is followed by using short fragments of constitutively expressed genes to screen sugarcane Bacterial Artificial Chromosome (BAC) libraries to isolate their corresponding promoters. Lastly, it was attempted to develop a selection system for transgenic sugarcane based on resistance to the herbicide chlorosulfuron. A mutant acetolactate synthase (alsb) gene from tobacco, which has shown to confer resistance to the tobacco, was transformed into sugarcane callus. It was anticipated that this gene will confer chlorosulfuron resistance to transgenic sugarcane. If resistance is achieved, the corresponding sugarcane gene will be mutated via site-directed mutagenesis and checked if it also confers resistance to sugarcane. Results showed that although transgenic lines were generated, resistance development is still inconclusive. / AFRIKAANSE OPSOMMING: Suikerriet is ‘n kommersiële gewas wat verbou word as gevolg van die hoë hoeveelhede sukrose wat gestoor word in die volwasse tussenknope van die stam. Verskeie studies is al gedoen om suiker metabolisme in die gewas te ondersoek, sowel as om die sukrose opbrengs te verhoog. Huidige strategieë vir suikerriet verbetering word beywer deur middel van teel-programme of transgeniese manipulasie. Die kommersialiseëring van transgeniese gewasse word egter bemoeilik deur publieke wanpersepsies, sowel as regulatoriese uitdagings. Hierdie tesis beoog om boenoemde kwessies aan te spreek, deur middel van twee projekte. Die eerste projek poog om sukrose akkumulasie in sukerriet te verhoog. Dit was onderneem om die Arabidopsis thaliana vakuolere pirofosfatase (AtV-PPase) geen, wat verbind is met die mielie ubiquitien promoter, uit te druk in suikerriet kallus. Daar was verwag dat die verhoogde aktiwiteit van die tonoplast-gebonde AtV-PPase sal veroorsaak dat meer sukrose in die vakuool akkumuleer. Oplosbare suiker inhoud was getoets in transgeniese suikerriet kallus lyne, maar geen merkbare verhoging in sukrose inhoud was waargeneem nie. Hierdie mag egter verander met verdere ondersoeke in suikerriet suspensie-kulture en glashuis-plante. Die tweede projek het beywer om ‘n nuwe suikerriet transformasie tegnologie te ontwikkel, wat slegs van suikerriet genetiese materiaal gebruik maak. Hierdie ‘cisgeniese’ benadering tot suikerriet transformasie sal ‘n inheemse suikerriet promoter, terminator, vektor ruggraat en seleksie-merker, benodig. Dit was eers beoog om ‘n funksionele promoter te isoleer, sowel as om ‘n seleksie sisteem, gebasseer op ‘n inheemse seleksie merker, te ontwikkel. Deur gebruik te maak van primers wat op ‘n sorghum templaat gebasseer is, was ‘n promotor geisoleer vanuit suikerriet; die uitdrukking hiervan is bepaal deur gebruik te maak van ‘n GFP verklikker geen. Ongelukkig kon uitdrukking nie bevestig word in transgeniese suikerriet kallus nie. Tans word suikerriet Kunsmatige Bakterieële Chromosoom (KBC) biblioteke geskandeer, deur gebruik te maak van geen-fragmente van globaal-uitgedrukte gene, om ooreenstemmende suikerriet promoters te isoleer. Die tweede deel van die cisgeniese projek het beoog om ‘n seleksie sisteem vir transgeniese suikerriet te ontwikkel, wat gebasseer is op weerstand teen die plantdoder chlorosulfuron. Suikerriet kallus was getranformeer met ‘n mutante tabak geen – asektolaktaat sintase (alsb) – wat chlorosulfuron weerstand in tabak meebring. Daar was verwag dat die geen chlorosulfuron weerstand aan transgeniese suikerriet sou oordra. Indien weerstand ontwikkel, sal die ooreenstemende suikerriet geen deur gerigte mutagenese gemuteer word; dan sal dit kan bepaal word of weerstand ook oorgedra word aan suikerriet. Daar is bevind dat alhoewel transgeniese lyne gegenereer is, daar steeds nie ‘n konklusiewe bevestiging van weerstand ontwikkeling is nie.
187

Comportamento da associação entre os herbicidas glifosato e atrazina em um Latossolo vermelho-escuro do bioma cerrado brasileiro / Behavior of glyphosate and atrazine herbicides applied in association in a Oxisoil from Brazilian Cerrado

Eloana Janice Bonfleur 18 June 2010 (has links)
O uso da associação entre glifosato e atrazina para a cultura do milho geneticamente modificado tolerante ao glifosato é uma das opções de controle de plantas daninhas nesta cultura. Portanto, o objetivo principal desse trabalho foi avaliar a influência do uso desta associação em um Latossolo vermelho-escuro proveniente do bioma Cerrado do Brasil através dos ensaios de degradação e mineralização desses herbicidas, carbono da biomassa microbiana e carbono mineralizado pelo solo. Os tratamentos para os ensaios de mineralização e degradação constaram da combinação entre 14C-glifosato na dose de campo (2,88Kg ha-1) a 0, 1/2, 1 e 2 vezes a dose de campo de atrazina (3,00Kg ha-1) e 14C-atrazina na dose de campo a 0, 1/2, 1 e 2 vezes a dose de campo de glifosato. A mineralização dos herbicidas foi medida aos 0, 3, 7, 14, 21, 28, 35, 42, 49, 56 e 63 dias e a degradação aos 0, 7, 28 e 63 dias após o início do experimento. A avaliação do carbono da biomassa microbiana foi realizada aos 21 e 63 dias após o início do ensaio e foram utilizados os mesmos tratamentos com a inclusão de uma prova em branco (solo sem herbicida). O ensaio de mineralização de carbono pelo solo foi feito através da quantificação do CO2 desprendido aos 3, 7, 14, 21, 28, 35, 42, 49, 56 e 63 dias após o início do ensaio, e também teve a inclusão de uma prova em branco. Os resultados demonstraram influência na degradação e mineralização da atrazina devido a presença do glifosato. A meia-vida de mineralização de atrazina teve uma variação de aproximadamente 100 dias quando foi comparada a aplicação individual de atrazina a associação com o dobro da dose de glifosato. A influência da atrazina na degradação e mineralização de glifosato não foi nítida. A presença de atrazina provocou queda no carbono da biomassa microbiana do solo e ocorreu um aumento na velocidade e quantidade de carbono mineralizado pelo solo. Não houve alteração no carbono da biomassa microbiana do solo e mineralização de carbono pelo solo devido a adição de glifosato. Nos tratamentos em associação, a presença do glifosato no sistema impediu a redução da biomassa microbiana devido ao efeito da atrazina. A associação entre glifosato e atrazina favoreceu a mineralização de carbono pelo solo comparada a aplicação individual de glifosato. Esses resultados demonstram a necessidade por parte da pesquisa em considerar a possibilidade de interação entre os diversos xenobióticos, o que pode alterar seus comportamentos individuais no solo. / The use of glyphosate and atrazine in association for transgenic corn tolerant to glyphosate is an option to weed control in this case. Therefore, the aim of this work was to assess the influence of this association in an Oxisoil from Brazil through the degradation, mineralization, microbial biomass and carbon mineralization of soil tests. The treatments of mineralization and degradation tests consisted of the combination between 14C-glyphosate in the field rate (2,88Kg ha-1) and 0, ½, 1 and 2 times the field rate of atrazine (3,00Kg ha-1). The mineralization of herbicides was measured at 0, 3, 7, 14, 21, 28, 35, 42, 49, 56, and 63 days and the degradation was measured at 0, 7, 28 and 63 days after the beginning of the tests. The evaluation of microbial biomass was performed at 21 and 63 days after the beginning of the test and was used the same treatments of the degradation and mineralization tests, but it was included a control (soil without application of herbicides). The test of carbon mineralization of soil was done by measuring the CO2 evolved at 0,7, 14, 21, 28, 35, 42, 49, 56 and 63 days after the beginning of the test and had the same control of the microbial biomass test. The results showed an influence on degradation and mineralization of atrazine due to the presence of glyphosate. The half-life of atrazine mineralization had a variation of about 100 days when it was compared the atrazine application alone to its association with glyphosate at double rate. The influence of atrazine in degradation and mineralization of glyphosate wasnt clear. The presence of atrazine caused decrease in the microbial biomass of soil and occurred an increase in speedy and amount of carbon mineralized by soil. No change was observed in microbial biomass and carbon mineralized by soil due to glyphosate application. In the treatments that was used the association, the presence of glyphosate in the system prevented decrease of microbial biomass due to the effect of atrazine. The association between glyphosate and atrazine favored the carbon mineralization by soil when compared to glyphosate applied alone. These results demonstrate a need to consider the possibility of interactions between several xenobiotics, wich can modify their behaviors in the soil.
188

Transformações no espaço agrário paraibano: práticas agroecológicas e luta pela soberania alimentar das Guardiãs das Sementes da Paixão do Polo da Borborema

Alves, Luciene Andrade 31 August 2018 (has links)
Submitted by FABIANA DA SILVA FRANÇA (fabiana21franca@gmail.com) on 2018-02-01T15:49:16Z No. of bitstreams: 1 Arquivo Total.pdf: 2396297 bytes, checksum: 67ed3b1d6a12c462e89a5cafd47fe5e5 (MD5) / Made available in DSpace on 2018-02-01T15:49:16Z (GMT). No. of bitstreams: 1 Arquivo Total.pdf: 2396297 bytes, checksum: 67ed3b1d6a12c462e89a5cafd47fe5e5 (MD5) Previous issue date: 2018-08-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This dissertation presents the strategy of collective organization of Polo da Borborema, with reference to the promotion of agroecological practices. The production of the foods that are in the table of the Brazilians comes from the work of the peasants and, in the case of Polo, these foods are produced from the action of rescue and maintenance of the creole seeds, known in the state of Paraíba as “Sementes da Paixão”. Among the strategies adopted by Polo in order to guarantee food sovereignty, there is the creation of Community Seed Banks. The valorization of agrobiodiversity from the specificity of Polo da Borborema organization serves as the basis for the analysis of the worldwide diffusion of research development and use of Genetically Modified Organisms in agriculture. Currently, Brazil has the second largest area planted with seeds of this type, which encourages debate on agrobiodiversity. The objective of this research was to understand how the actions of Polo da Borborema focused on the valorization of agroecology and protection of agrobiodiversity have influenced the awareness of the women of Polo as to their role for the peasant family agriculture. The research was carried out between the years of 2015 and 2017, when fieldwork was carried out, in which the farmers and leaders of the union were interviewed, as well as participation in events, with emphasis on the " March for Women's Lives and for Agroecology. " The encouragement of the participation of women in the various activities organized by Polo has represented an important movement to raise awareness about their contribution to the production of healthy foods, the valorization of the "Sementes da Paixão", as well as in awakening to the collective struggle and organized by the construction of egalitarian gender relations. / Esta dissertação apresenta a estratégia de organização coletiva do Polo da Borborema, tendo como referência a promoção de práticas agroecológicas. A produção dos alimentos que estão na mesa dos brasileiros é proveniente do trabalho dos (as) agricultores (as) camponeses (as) e, no caso do Polo, estes alimentos são produzidos a partir da ação de resgate e manutenção das sementes crioulas, conhecidas no estado da Paraíba como “Sementes da Paixão”. Dentre as estratégias adotadas pelo Polo no intuito de se garantir soberania alimentar, está a criação dos Bancos de Sementes Comunitários. A valorização da agrobiodiversidade a partir da especificidade da organização do Polo da Borborema serve de base para a análise sobre a difusão mundial do desenvolvimento de pesquisas e uso de Organismos Geneticamente Modificados na agricultura. Atualmente, o Brasil possui a segunda maior área plantada de sementes deste tipo, o que fomenta o debate a respeito da agrobiodiversidade. O objetivo desta pesquisa foi compreender como as ações do Polo da Borborema voltadas à valorização da agroecologia e proteção da agrobiodiversidade têm influenciado na tomada de consciência das mulheres do Polo quanto ao seu papel para a agricultura familiar camponesa. A pesquisa foi desenvolvida entre os anos de 2015 e 2017, quando foram realizados trabalhos de campo, em que foram entrevistados (as) agricultores (as) e lideranças da organização sindical, além de ter ocorrido a participação em eventos, com destaque para a “Marcha pela Vida das Mulheres e pela Agroecologia”. O incentivo à participação das mulheres nas diversas atividades organizadas pelo Polo tem representado importante movimento de tomada de consciência das mesmas quanto à sua contribuição na produção de alimentos saudáveis, na valorização das “Sementes da Paixão”, bem como no despertar para a luta coletiva e organizada pela construção de relações de gênero igualitárias.
189

Genetically modified (GM) maize cultivation by smallholders in the Eastern Cape Province of South Africa: Effects on target and non-target organisms and adoption challenges

Kotey, Daniel Ashie January 2017 (has links)
The use of genetically modified (GM) maize technology is subject to compliance with stewardship requirements and the adoption of specific management practices that promote the long-term effectiveness and environmental sustainability of the technology. For smallholders to comply with these requirements and adopt the desired management practices to ultimately benefit from the technology, they require information that creates awareness of the value of these requirements. To determine what information farmers receive about GM maize and how this information is disseminated to farmers, face to face interviews were conducted with 81 extension personnel and 210 smallhoder GM maize farmers in the Eastern Cape Province of South Africa. The effect of Bt maize introduction and management practices in smallholder maize agroecosystems in the Eastern Cape on Bt maize target [Busseola fusca (Fuller) (Lepidoptera: Noctuidae)] and non-target insect pests [Agrotis segetum (Denis & Schiffermüller) (Lepidoptera: Noctuidae), Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)] and a snail species, [Cornu aspersum (Müller) (Gastropoda: Helicidae)] was determined through laboratory, field and cage experiments. The effect of smallhoder farmers‟ GM maize cultivation practices on the profitability of GM maize technology was also determined through on-farm trials in different localities of the Eastern Cape identified as hot-spots for stem borer and weed infestation. Results of surveys indicated that extension personnel had a low level of awareness of GM maize technology stewardship requirements. GM maize technology was also largely disseminated to smallholder farmers through non-participatory approaches and print media sourced from GM seed companies. Although farmers had a high level of contact with extension services, they lacked access to information about GM maize technology. Smallholder farmers‟ level of awareness about GM maize and compliance with the requirement for the planting of non-Bt maize refuge areas adjacent to Bt maize was also very low. While Bt maize event (MON810) commonly cultivated by smallholder farmers in the Eastern Cape Province had a variable effect on A. segetum under laboratory conditions, it had no effect on the incidence of plants damaged by A. segetum and C. aspersum under field conditions. The incidence of H. armigera damage on Bt maize plants was however significantly affected by Bt maize. Populations of B. fusca collected from smallholder maize fields in the province were observed to be still highly susceptible to Bt maize. Results of on-farm evaluation of the profitability of GM maize revealed that stem borer pressure, growing conditions, input supplies and market access affect the productivity and profitability of GM maize cultivation. Challenges within the extension and advisory services of the Eastern Cape which can militate against smallholder farmers‟ ability to benefit from GM maize technology and sustain the long-term efficacy of the technology were identified during this study. Given these challenges and the fact that the cultivation of GM maize may not be profitable under typical smallholder maize cultivation conditions and management practices, dissemination approaches that provide farmers the opportunity to evaluate GM maize technology alongside alternate technologies under their conditions, may prove beneficial.
190

Vývoj a optimalizace metodiky pro detekci GMO brambor / Development and optimalization of methodology for detection of GMO potatoes

ČERMÁKOVÁ, Jitka January 2008 (has links)
Genetically modified (GM) or transgenic crops, now more often called ``Biotech crops{\crqq} they are commercially cultivated since 1996. And also since 1996, the first year of commercialization of biotech crops, GM potatoes were cultivated in USA, Mexico, Canada and later in South Africa, China and India. The global area of approved biotech crops in 2006 was 102 million hectares and 22 countries grew biotech crops, 11 developing countries and 11 industrial countries. The Czech Republic is on of the six EU countries where biotech crops are cultivated at present. The most compelling case for biotechnology, and more specifically biotech crops, is their capability to contribute to: increasing crop productivity and stability of productivity and production; conserving biodiversity, as a land-saving technology; the production of renewable resource based bio-fuels. This diploma paper was focused on developing of fast, precise and cheap method based on PCR to detect the presence of transgenes in potatoes {--} tubers and leaves, allows monitoring the presence of GM potatoes in market, environment, etc. and to quantify ``contamination{\crqq} of ware potatoes (tubers) with GM ones.

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