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Genetically modified (GM) crops were introduced in South Africa in 1989 and commercially available by 1998. Legislation to control the use of GM crops was only implemented in 1999, with the genetically modified organisms (GMO) act (15 of 1999). In 2012 2.9 million ha of GM crops were planted in South Africa alone. GM Crops, such as Bt maize, are promoted as safer for the environment since no chemical pesticides are needed. However, recently GM crops have been making headlines as more and more studies find adverse effects of these crops on non-target organisms. The effects on aquatic environments have not yet been fully determined, even though traces of Bt residue have been found in water systems surrounding agricultural lands. The aim of this study was to establish the effects of the Bt toxin on fecundity, development and growth of Bulinus tropicus, a freshwater snail. The experiment made use of a static renewal tests to expose B. tropicus to 50 cm2 Bt maize and cotton leaves in 900 ml of synthetic freshwater. The snails were exposed for the duration of one full life cycle (embryo to adult). Endpoints measured included the development, growth, fecundity, and deformities of the reproductive organs. The results obtained showed retarded development and low embryo survival when the snails were exposed to cotton leaves, irrespective of the presence or absence of Bt, indicating to the possibility of trace residues of chemical pesticides may have been present on the leaves. Initial stimulated growth of hatchlings was observed for both Bt cotton and maize exposures, but after sexual maturity has been reached, ‘surplus’ energy was probably shared between growth and fecundity, resulting in a reduction of growth rate. Energy is gained from their diet, thus a sub-optimal diet would result in less energy available to functions such as growth and fecundity. Signs of developmental instability were found in the formation of the shell opening of the snails exposed to Bt. Fecundity decreased significantly after snails had been exposed to Bt maize / cotton leaves. No differences were found in the penis sheath-preputium length ratio, indicating that Bt had no deleterious effects on the reproductive organs. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2014

Genetically modified (GM) crops were introduced in South Africa in 1989 and commercially available by 1998. Legislation to control the use of GM crops was only implemented in 1999, with the genetically modified organisms (GMO) act (15 of 1999). In 2012 2.9 million ha of GM crops were planted in South Africa alone. GM Crops, such as Bt maize, are promoted as safer for the environment since no chemical pesticides are needed. However, recently GM crops have been making headlines as more and more studies find adverse effects of these crops on non-target organisms. The effects on aquatic environments have not yet been fully determined, even though traces of Bt residue have been found in water systems surrounding agricultural lands. The aim of this study was to establish the effects of the Bt toxin on fecundity, development and growth of Bulinus tropicus, a freshwater snail. The experiment made use of a static renewal tests to expose B. tropicus to 50 cm2 Bt maize and cotton leaves in 900 ml of synthetic freshwater. The snails were exposed for the duration of one full life cycle (embryo to adult). Endpoints measured included the development, growth, fecundity, and deformities of the reproductive organs. The results obtained showed retarded development and low embryo survival when the snails were exposed to cotton leaves, irrespective of the presence or absence of Bt, indicating to the possibility of trace residues of chemical pesticides may have been present on the leaves. Initial stimulated growth of hatchlings was observed for both Bt cotton and maize exposures, but after sexual maturity has been reached, ‘surplus’ energy was probably shared between growth and fecundity, resulting in a reduction of growth rate. Energy is gained from their diet, thus a sub-optimal diet would result in less energy available to functions such as growth and fecundity. Signs of developmental instability were found in the formation of the shell opening of the snails exposed to Bt. Fecundity decreased significantly after snails had been exposed to Bt maize / cotton leaves. No differences were found in the penis sheath-preputium length ratio, indicating that Bt had no deleterious effects on the reproductive organs. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2014

A planta daninha Amaranthus palmeri é nativa dos Estados Unidos, porém foi pela primeira vez relatada no Brasil no ano de 2015. Embora comprovadamente com resistência múltipla aos herbicidas inibidores da ALS e da EPSPS, até o momento não foram investigadas as bases moleculares da resistência. Além disso, por causa da recente introdução da planta daninha no país, alternativas de manejo com culturas tolerantes a herbicidas necessitam ser estudadas. Sendo assim, os objetivos desse trabalho são de caracterizar a espécie de planta daninha introduzida no país, identificar os mecanismos de resistência aos herbicidas inibidores da ALS e da EPSPS presentes no biótipo, e propor abordagens de manejo em ambientes dos novos eventos transgênicos resistentes a herbicidas. Um bioensaio utilizando marcadores genéticos foi desenvolvido para confirmar que a população coletada no estado do Mato Grosso (BR-R) é A. palmeri, e não A. tuberculatus, outra espécie dióica do gênero Amaranthus. Os resultados de experimentos de curvas de dose-resposta e acúmulo de chiquimato indicaram que a BR-R possui alto nível de resistência, com DL50 de 4.426 e 3.400 g glyphosate ha-1 no primeiro e segundo experimento, respectivamente, mais que o dobro da dose típicamente recomendada para o controle da espécie e, adicionalmente, observou se acúmulo mínimo de chiquimato a concentração de 1 mM nos tecidos das plantas tratadas com o herbicida. BR-R também foi resistente a herbicidas dos grupos químicos das sulfoniluréias e imidazolinonas. O mecanismo de resistência ao glyphosate encontrado nesta população foi a super expressão gência, através do aumento no número de cópias do gene da EPSPS no genoma da planta BR-R, entre 50 e 179 cópias adicionais. Além disso, duas substituições de aminoácidos foram observadas na sequência da ALS, W574L e S653N, conferindo resistência tanto a sulfoniluréias quanto a imidazolinonas. No experimento utilizandos os herbicidas correspondentes às culturas geneticamente modificadas com novos traits de tolerância a herbicidas observou se, de uma forma geral, que as associações de herbicidas apresentaram níveis de controle mais satisfatórios. Assim, esta pesquisa confirma a introdução de da espécie A. palmeri no Brasil, assim como a resistência múltipla aos herbicidas inibidores da EPSPS e da ALS. Seu manejo é mais eficaz através da associação de herbicidas, garantindo assim o uso racional das novas tecnologias de culturas geneticamente modificadas com tolerância a herbicidas. / Palmer Amaranth (Amaranthus palmeri) is a weed species native to the United States, but it was reported in Brazil for the first time in 2015. Despite this population being resistant to EPSPS and ALS inhibitors, the molecular basis of its multiple resistance is unknown up to date. Because of this species introduction to Brazil, alternatives of management with the new herbicide-tolerant crops technologies need to be studied. The objectives of this research are to characterize the weed species introduced to Brazil, identify the mechanisms conferring resistance to ALS and EPSPS inhibitors herbicides, and to propose management approaches in environments with the new genetically modified herbicide-tolerant crops. A genotyping bioassay using genetic markers was developed to confirm that the species collected in the state of Mato Grosso (BR-R) is indeed A. palmeri and not A. tuberculatus, another dioceous species in the Amaranthus genus. Dose-response experiments and shikimate accumulation bioassay data indicate high level of resistance, with LD50 of 4,426 and 3,400 g glyphosate ha-1 in the first and second experiments, respectively, higher than the double rate tipically recommended to control it, and minimal accumulation in BR-R with 1 mM of glyphosate in treated plants in the leaf disks assay. BR-R also was resistanto to sulfonilurea and imidazolinone herbicides. The mechanism conferring resistance to glyphosate identified in this population was gene amplification, with increased EPSPS copy number - between 50 and 179 more copies in BR-R. Besides, two target-site mutations were identified in the ALS gene sequencing, W574L and S653N, conferring resistance to sulfonilureas and imidazolinones. The weed control experiment, overal, herbicide tank mixtures achieved higher levels of control. Therefore, this research confirms the introduction of A. palmeri to Brazil, as well as its multiple resistance to EPSPS and ALS inhibitor herbicides. Its control is more efficient with herbicide mixtures, which guarantees more susteinable use of the new herbicide-tolerant crop technologies.

A planta daninha Amaranthus palmeri é nativa dos Estados Unidos, porém foi pela primeira vez relatada no Brasil no ano de 2015. Embora comprovadamente com resistência múltipla aos herbicidas inibidores da ALS e da EPSPS, até o momento não foram investigadas as bases moleculares da resistência. Além disso, por causa da recente introdução da planta daninha no país, alternativas de manejo com culturas tolerantes a herbicidas necessitam ser estudadas. Sendo assim, os objetivos desse trabalho são de caracterizar a espécie de planta daninha introduzida no país, identificar os mecanismos de resistência aos herbicidas inibidores da ALS e da EPSPS presentes no biótipo, e propor abordagens de manejo em ambientes dos novos eventos transgênicos resistentes a herbicidas. Um bioensaio utilizando marcadores genéticos foi desenvolvido para confirmar que a população coletada no estado do Mato Grosso (BR-R) é A. palmeri, e não A. tuberculatus, outra espécie dióica do gênero Amaranthus. Os resultados de experimentos de curvas de dose-resposta e acúmulo de chiquimato indicaram que a BR-R possui alto nível de resistência, com DL50 de 4.426 e 3.400 g glyphosate ha-1 no primeiro e segundo experimento, respectivamente, mais que o dobro da dose típicamente recomendada para o controle da espécie e, adicionalmente, observou se acúmulo mínimo de chiquimato a concentração de 1 mM nos tecidos das plantas tratadas com o herbicida. BR-R também foi resistente a herbicidas dos grupos químicos das sulfoniluréias e imidazolinonas. O mecanismo de resistência ao glyphosate encontrado nesta população foi a super expressão gência, através do aumento no número de cópias do gene da EPSPS no genoma da planta BR-R, entre 50 e 179 cópias adicionais. Além disso, duas substituições de aminoácidos foram observadas na sequência da ALS, W574L e S653N, conferindo resistência tanto a sulfoniluréias quanto a imidazolinonas. No experimento utilizandos os herbicidas correspondentes às culturas geneticamente modificadas com novos traits de tolerância a herbicidas observou se, de uma forma geral, que as associações de herbicidas apresentaram níveis de controle mais satisfatórios. Assim, esta pesquisa confirma a introdução de da espécie A. palmeri no Brasil, assim como a resistência múltipla aos herbicidas inibidores da EPSPS e da ALS. Seu manejo é mais eficaz através da associação de herbicidas, garantindo assim o uso racional das novas tecnologias de culturas geneticamente modificadas com tolerância a herbicidas. / Palmer Amaranth (Amaranthus palmeri) is a weed species native to the United States, but it was reported in Brazil for the first time in 2015. Despite this population being resistant to EPSPS and ALS inhibitors, the molecular basis of its multiple resistance is unknown up to date. Because of this species introduction to Brazil, alternatives of management with the new herbicide-tolerant crops technologies need to be studied. The objectives of this research are to characterize the weed species introduced to Brazil, identify the mechanisms conferring resistance to ALS and EPSPS inhibitors herbicides, and to propose management approaches in environments with the new genetically modified herbicide-tolerant crops. A genotyping bioassay using genetic markers was developed to confirm that the species collected in the state of Mato Grosso (BR-R) is indeed A. palmeri and not A. tuberculatus, another dioceous species in the Amaranthus genus. Dose-response experiments and shikimate accumulation bioassay data indicate high level of resistance, with LD50 of 4,426 and 3,400 g glyphosate ha-1 in the first and second experiments, respectively, higher than the double rate tipically recommended to control it, and minimal accumulation in BR-R with 1 mM of glyphosate in treated plants in the leaf disks assay. BR-R also was resistanto to sulfonilurea and imidazolinone herbicides. The mechanism conferring resistance to glyphosate identified in this population was gene amplification, with increased EPSPS copy number - between 50 and 179 more copies in BR-R. Besides, two target-site mutations were identified in the ALS gene sequencing, W574L and S653N, conferring resistance to sulfonilureas and imidazolinones. The weed control experiment, overal, herbicide tank mixtures achieved higher levels of control. Therefore, this research confirms the introduction of A. palmeri to Brazil, as well as its multiple resistance to EPSPS and ALS inhibitor herbicides. Its control is more efficient with herbicide mixtures, which guarantees more susteinable use of the new herbicide-tolerant crop technologies.

This thesis looks at the divergent policy decisions on the commercial release of two genetically modified (GM) crops in India. Bt cotton was introduced in India in 2002, and has spread widely across the country, though not without controversy. In 2010, the first GM food crop – Bt Brinjal (eggplant) – was put forward for approval. In contrast to the Bt cotton decision, and following heated debate and a series of public consultations across the country, an indefinite moratorium was placed on the crop. In this thesis, I unpack the various factors that shaped both decisions and the politics that accompanied them. To facilitate this analysis, I use a conceptual framework that combines four key forces that are often the focus of food governance analysis, but which are not always considered together. I argue that the divergence in outcomes can be explained by a confluence of shifts in key elements of the policy process. These dimensions of influence can be understood in four related categories: corporate actors, institutional mechanisms, science and science networks, and discursive elements. Changes that took place in each of these dimensions in the period between the two decisions align to explain divergent outcomes that no individual influence could. The conceptual framework I develop in this thesis presents a useful structure to analyse the often-complex and multi-causal processes and outcomes related to food and environmental issues. The results of this research have implications for the future direction of agricultural GMO policy in India, as well as in other countries in the global South.

This thesis looks at the divergent policy decisions on the commercial release of two genetically modified (GM) crops in India. Bt cotton was introduced in India in 2002, and has spread widely across the country, though not without controversy. In 2010, the first GM food crop – Bt Brinjal (eggplant) – was put forward for approval. In contrast to the Bt cotton decision, and following heated debate and a series of public consultations across the country, an indefinite moratorium was placed on the crop. In this thesis, I unpack the various factors that shaped both decisions and the politics that accompanied them. To facilitate this analysis, I use a conceptual framework that combines four key forces that are often the focus of food governance analysis, but which are not always considered together. I argue that the divergence in outcomes can be explained by a confluence of shifts in key elements of the policy process. These dimensions of influence can be understood in four related categories: corporate actors, institutional mechanisms, science and science networks, and discursive elements. Changes that took place in each of these dimensions in the period between the two decisions align to explain divergent outcomes that no individual influence could. The conceptual framework I develop in this thesis presents a useful structure to analyse the often-complex and multi-causal processes and outcomes related to food and environmental issues. The results of this research have implications for the future direction of agricultural GMO policy in India, as well as in other countries in the global South.