Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2016-10-10T18:02:00Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Vera - TESE (Com ficha catalográfica).pdf: 1807916 bytes, checksum: b10e55b1c51122e4e4037d88c42bda62 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2016-10-11T20:53:39Z (GMT) No. of bitstreams: 2 Vera - TESE (Com ficha catalográfica).pdf: 1807916 bytes, checksum: b10e55b1c51122e4e4037d88c42bda62 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-10-11T20:53:39Z (GMT). No. of bitstreams: 2 Vera - TESE (Com ficha catalográfica).pdf: 1807916 bytes, checksum: b10e55b1c51122e4e4037d88c42bda62 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2014-03-27 / Sem bolsa / O Brasil é considerado um dos países que mais produz resíduos agroindustriais, devido à intensa atividade agrícola. Como exemplo deste fato destaca-se a quirera de arroz,o bagaço de uva ea farinha de soja que podem ser aproveitados como ingredientes na elaboração de novos produtos para a alimentação humana. Objetivou-se com esteestudo, caracterizar nutricionalmente misturas à base de arroz parboilizado, farinha de soja desengordurada e bagaço de uva e seus efeitos nos parâmetros biológicos de ratos Wistar após desmame, visando alternativas para uma alimentação saudável na fase de crescimento. O trabalho foi estruturado em dois experimentos, onde no Experimento I foram comparados, parâmetros nutricionais e microbiológicos, compostos fenólicos,antocianinas e atividade antioxidante em arroz parboilizado, farinha de soja desengordurada e bagaço de uva. No Experimento II foram avaliadas as respostas biológicas de ratos machos Wistarem crescimento,alimentados com dietas contendo diferentes proporções de arroz parboilizado, farinha de soja e bagaço de uva. Os resultados permitem concluir que a maior concentração de soja no suplemento, causa ganho de peso, aumento no colesterol, na glicose e na gordura epididimal, entretanto promove o crescimento.O aumento da concentração de arroz e bagaço de uva no suplemento, provoca aumento na área do fêmur, diminui os níveis de triglicerídeos e não altera os níveis de colesterol e gordura epididimal.A suplementação com arroz, soja e bagaço de uva, não provoca alteração na função hepática, sendo possível a sua utilização na alimentação no período de crescimento. / Brazil is considered one of the countries that more agro-industrial waste produced, due to the intense agricultural activity. As an example of this fact is the Grits of grape bagasse, rice and soy flour that can be used as ingredients in the preparation of new products for human consumption. The objective of this study, to characterize nutritionally mixtures with a basis of parboiled rice, defatted soy flour and grape Marc and their effects on biological parameters of Wistar rats after weaning, seeking alternatives for a healthy nutrition in growth phase. The work was structured in two experiments, where in experiment I were compared, nutritional and microbiological parameters, phenolic compounds, anthocyanins and antioxidant activity in parboiled rice, soy flour, defatted and grape marc. In experiment II were evaluated the biological responses of male Wistar rats in growth, fed with diets containing different proportions of parboiled rice, soy flour and grape marc. The results allow to conclude that the greatest concentration of soybean in the supplement, cause weight gain, increase in cholesterol, glucose and epididymal fat, however promotes growth. The increase in concentration of rice and grape Marc in the supplement, causes an increase in the area of the femur, decreases triglyceride levels and does not alter the levels of cholesterol and epididymal fat. Supplementation with rice, soya and grape residue, does not cause change in liver function and its use in feed on growth period.

Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2017-02-08T14:22:01Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertação.pdf: 1451490 bytes, checksum: 8db111be8fc2a2a277ed6aa88f84a6e6 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-02-15T16:51:40Z (GMT) No. of bitstreams: 2 dissertação.pdf: 1451490 bytes, checksum: 8db111be8fc2a2a277ed6aa88f84a6e6 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-02-15T16:51:40Z (GMT). No. of bitstreams: 2 dissertação.pdf: 1451490 bytes, checksum: 8db111be8fc2a2a277ed6aa88f84a6e6 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2013-06-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / As raízes possuem uma grande variedade de funções nas plantas, incluindo absorção de água, nutrientes e suporte estrutural. A combinação de métodos clássicos de genética e melhoramento com tecnologias moleculares de análise genômica abre uma nova perspectiva para a ampliação do conhecimento das bases genéticas e aceleração de programas de melhoramento. A maioria dos conhecimentos sobre as redes gênicas envolvidas no desenvolvimento radicular vem sendo acumuladas na espécie Arabidopsis thaliana, modelo de planta dicotiledônea. O entendimento dos mecanismos envolvidos na regulação da expressão dos genes é essencial para compreender a forma e a função dos sistemas. Os elementos cis-acting são regiões do DNA que atuam como interruptores moleculares envolvidos na regulação da transcrição de uma rede gênica dinâmica. Embora freqüentemente tenham somente cinco a 20 pb de tamanho, os elementos cis-acting são críticos para o entendimento da regulação gênica. O conhecimento destes elementos presentes na região promotora de famílias gênicas, poderá contribuir para a compreensão dos sistemas reguladores da expressão da rede gênica envolvida na formação do sistema radicular. O objetivo desse trabalho é identificar os elementos cis-acting presentes na região promotora de genes de arroz (Oryza sativa subsp japonica cv. Nipponbare) similares aos genes das famílias Argonauta, Cullin e Arade Arabidopsis thaliana. A região promotora dos genes destas famílias no arroz foi investigada quanto à abundância destes elementos. As seqüências foram analisadas utilizando o programa “Signal Scan Search” do portal “Plant Cis-acting Regulatory DNA Elements” (PLACE) para a identificação dos diferentes elementos cis-acting. Foram detectados 96 diferentes elementos, sendo cinco destes (GAREAT (TAACAAR), TGACGTVMAMY (TGACGT), CCAATBOX1 (CCAAT), LECPLEACS2 (TAAAATAT) e SV40COREENHAN (GTGGWWHG), comuns as famílias gênicas Argonauta, Cullin e Ara. / The roots have a large range of functions in plants, including acquisition of water and nutrients, as well as structural support. The combination of classical methods of genetics and breeding with molecular technologies for genomic analysis opens a new perspective to expand the knowledge of the genetic basis and to accelerate breeding programs. The most advanced knowledge regarding gene networks involved in root development has been obtained in the model dicotyledon plant species Arabidopsis thaliana. Understanding the mechanisms involved in regulation of gene expression is essential to predict the form and function of systems. Cis-actingelements are DNA regions that act as molecular switches involved in the regulation of transcription of dynamic gene network. Although often having only five to 20 bp in size, cis-actingelements are critical to the understanding of gene regulation. Knowledge of the cis-acting elements present in the promoter region of gene families, can contribute to the understanding of the expression regulatory systems of these genes and others, involved with the root system. The objective of this study is to identify the cisacting elements present in the upstream region of rice (Oryza sativa subsp japonica cv. Nipponbare) genes, similar to gene families Argonauta, Cullin and Arain Arabidopsis thaliana. The promoter region of these rice gene families were investigated for the abundance of cis-acting elements. The sequences were analyzed using the software “Signal Scan Search” ofthe website “Plant Cis-acting Regulatory DNA Elements” (PLACE) to the identification of different cis-acting elements. It were detected 96 different cis-acting elements, and five of these, (GAREAT (TAACAAR), TGACGTVMAMY (TGACGT), CCAATBOX1 (CCAAT), LECPLEACS2 (TAAAATAT) e SV40COREENHAN (GTGGWWHG) were common to the gene families Argonauta, Cullin andAra.

Made available in DSpace on 2014-08-20T13:44:37Z (GMT). No. of bitstreams: 1 dissertacao_clarissa_da_silva.pdf: 333325 bytes, checksum: 487ed9f3127ccb664dcea12fed6e7838 (MD5) Previous issue date: 2007-03-15 / This work was conducted to evaluate the quality of rice seeds treated whit fungicide in different moisture contents during of stored period. Were used two rice seeds lots, cv EL PASO 144, produced in Pelotas/RS during 04/05. For the formularization of fungicide, were additioned 10mL (1%), 20mL (2%) e 30mL (3%) of water in mixed with fungicide Carboxin/Thiram (300mL/ 100Kg of seeds). Same water percentages, without addition of the fungicide, besides one control, had constituted the seven treatments. The seeds were stored in hermetic recipient during eight months period. The quality of seeds was submitted to moisture determination, standard germination, vigor and health. Biochemical evaluation of the seeds was obtained by the technique of electrophoresis of enzymatic systems, being evaluated the activity of the enzymes Acid Phosphates, Alcohol Dehydrogenize, Glutamate Oxalacetate Transaminase, Esterase and a- amylase. The statistic model was of randomizes completely blocks with three replications. The benefic effect of fungicide on physiological quality are evident immediately after the treatment of seeds. The results indicate the germination and vigor reduction of treated seeds increase after 60 days of storage. The fungicide used in treatments of seeds is efficient in reduction of the fungi associates on the rice seeds. Wasn t possible to identify the effect of fungicide in the expression of enzymes of viable seeds. / Este trabalho foi conduzido com objetivo avaliar a qualidade de sementes de arroz tratadas com fungicida em diferentes graus de umidade durante o período de armazenamento. Foram utilizados dois lotes de sementes da cultivar EL PASO 144, de diferentes graus de umidade e sanidade, produzidos na região de Pelotas, RS, na safra 04/05. Para a formulação da calda fungicida foram adicionados 10mL(1%), 20mL (2%), e 30mL (3%) de água em mistura com fungicida Carboxin/Thiram (300mL/100Kg de sementes). Mesmas percentagens de água, sem adição do fungicida, além de uma testemunha, constituíram os sete tratamentos. Após, foram embaladas em recipientes herméticos, durante o período de oito meses de armazenamento. A qualidade das sementes foi monitorada através do teste para determinação do grau de umidade, germinação, vigor e sanidade. Avaliações bioquímicas das sementes, através da técnica de eletroforese de sistemas enzimáticos, determinou-se a atividade das enzimas Fosfatase Ácida, Álcool Desidrogenase, Glutamato Oxalacetato Transaminase, Esterase e Alfa -amilase. O modelo estatístico utilizado foi o completamente casualizado, com três repetições. Os efeitos benéficos do tratamento fungicida sobre a qualidade fisiológica são evidentes logo após o tratamento das sementes. Os resultados obtidos demonstram decréscimo na porcentagem de germinação e vigor das sementes tratadas, intensificado a partir do 60º dia de armazenamento. O fungicida utilizado no tratamento de sementes é eficiente na redução da incidência de fungos associados à semente. Não foi possível detectar o efeito do fungicida na expressão das enzimas das sementes viáveis.

Made available in DSpace on 2014-08-20T13:59:08Z (GMT). No. of bitstreams: 1 dissertacao_cristina_larre.pdf: 291548 bytes, checksum: b01c0fd3c6e2185e8da8574384127853 (MD5) Previous issue date: 2008-05-30 / The objective of the research was evaluate the importance 24-epibrassinolide in physiological performance of rice seeds, for this two experiments were conducted in laboratory and a greenhouse. The first assessed the performance of different concentrations of 24-epibrassinolide in physiological quality of seeds and seedlings grow th in tw o lots of rice cv. IRGA 422CL. The seeds of both lots were treated with increasing concentrations of 24-epibrassinolide, zero, 0.01, 0.1, 0.4 and 1.0 µM, for a period of two hours and evaluated through the tests of germination, the first counting of germination, the speed of germination index , emergency , speed of emergency index , length of shoot and root and fresh and dry mass of shoot and root. Generally in all characteristics determined, concentrations less than or equal to 0.4 µM 24- epibrassinolide produced a positive response in physiological quality seeds of rice cv. IRGA 422CL. The second ex periment w as conducted w it h seed rice of tw o cultivars, BRS Querência, genoty pe susceptible to salinity and BRS Bojurú, tolerant to salt, in order to determine the effect of the 24-epibrassinolide on the germination, seedling grow th, leaf area and concentration of chlorophy ll under salt stress condition. Seeds w ere soaked for tw o hours in w ater, 100mM NaCl and solutions of 100 mM NaCl supplemented w ith 24-epibrassinolide at concentrati ons of 0.01, 0.1 and 1.0 µM. The viability and vigor of rice seeds of cv. BRS Querên cia w ere reduced by salinity and w ere restored by the application of the 24-epibrass inolide in concentration 1.0 µM. While in cv. BRS Bojurú the vigor w as reduced by th is concentration. The application of the 24-epibrassinolide in cv. BRS Querência incr eased the concentration of chlorophy ll, leaf area, length of root and shoot, f resh and dry mass of root and shoot, reducing the deleterious effects caused by salinity. H ow ever, in cv. BRS Bojurú, tolerant to salinity , the application of the 24-epi brassinolide 0.01 µM reversed or did not affect the characteristics of grow th, although, concentrations of 0.1 e 1,0 µM reduced the characteristics of grow th, but did not affect the chlorophy ll concentration. Based on the results, it can be inferred that the supplementation of saline solution w ith 24-epibrassinolide improves the q uality of see d varieties susceptible to salinity , not acting the same w ay in more tolerant cultivars. / O objetivo da pesq uisa foi avaliar a importância do 24-epibrassinolídeo no desempenho fisiológico de sementes de arroz, sendo realizados dois ex perimentos, em laboratório e casa de vegetação. O primeiro aval iou o desempenho de diferentes concentrações de 24-epibrassinolídeo na q ualidade f isiológica de sementes e no crescimento de plâ ntulas de arroz em dois lotes da cv. IRGA 422CL. As sementes de ambos os lotes foram tratadas com concentrações crescentes de 24- epibrassinolídeo (zero; 0,01; 0,1; 0,4 e 1,0 µM), por um período de duas horas e avaliadas por meio dos testes de germinação, primeira contagem da germinação, índice de velocidade de germinação, índice de velocidade de emergência, emergência, comprimento de parte aérea e raiz e massas fresca e seca de parte aérea e raiz. De modo geral em todas as características determinadas, concentrações menores ou iguais a 0,4 µM de 24-epibrassinolídeo produziram respostas positivas na q ualidade fisiológica das se mentes de arroz cv. IRGA 422CL. O segundo ex perimento foi conduzido com sementes de arroz de duas cultivares, BRS Querência, genótipo suscetível a salinidade e B RS Bojurú, tolerante ao sal, de modo a determinar o efeito do 24-epibrassinolídeo na germinação, crescimento de plântulas, área foliar e concentração de clorofila em condição de estresse salino. As sementes foram embebidas, por duas horas, em água, NaCl 100 mM e soluções de NaCl 100 mM suplementadas com 24-epibrassinolídeo nas concentrações de 0,01; 0,1 e 1,0 µM. A viabilidade e o vigor das sementes de arroz da cv. BRS Querência, foram reduzidos pela salinidade e restabelecidos pela aplicação do 24- epibrassinolídeo na concentração 1,0 µM. Enq uanto, na cv. BRS Bojurú, a aplicação desta concentração reduziu o vigor. Na cv. BRS Quer ência, suscetível ao sal, a aplicação do 24-epibrassinolídeo incrementou a concentração de clorofila, área foliar, comprimento de raiz e parte aérea, massas fresca e seca de raiz e parte aérea, reduzindo os efeitos deletérios causados pela salinidade. No entanto, na cv. BRS Bojurú, tolerante a salinidade, a aplicação do 24-epibrassinolídeo 0,01 µM reverteu ou não afetou as características de crescimento, porém, concentrações de 0,1 e 1,0 µM reduziram as características de cresci mento, mas não afetaram a concentração de clorofila. Com base nos resultados, pode-se inferir q ue a suplementação da solução salina com 24-epibrassinolídeo melhora a q ualidade das sementes de cultivares suscetíveis a salinidade, não atuando da mesma forma em cultivares mais tolerantes.

Made available in DSpace on 2014-08-20T13:59:09Z (GMT). No. of bitstreams: 1 dissertacao_cristina_ferreira_larre.pdf: 314474 bytes, checksum: 7bcfb3b381c500d52e92c9e1a37d5d9b (MD5) Previous issue date: 2008-05-30 / The objective of the research was evaluate the importance 24-epibrassinolide in physiological performance of rice seeds, for this two experiments were conducted in laboratory and a greenhouse. The first assessed the performance of different concentrations of 24-epibrassinolide in physiological quality of seeds and seedlings growth in two lots of rice cv. IRGA 422CL. The seeds of both lots were treated with increasing concentrations of 24-epibrassinolide, zero, 0.01, 0.1, 0.4 and 1.0 μM, for a period of two hours and evaluated through the tests of germination, the first counting of germination, the speed of germination index, emergency, speed of emergency index, length of shoot and root and fresh and dry mass of shoot and root. Generally in all characteristics determined, concentrations less than or equal to 0.4 μM 24- epibrassinolide produced a positive response in physiological quality seeds of rice cv. IRGA 422CL. The second experiment was conducted with seed rice of two cultivars, BRS Querência, genotype susceptible to salinity and BRS Bojurú, tolerant to salt, in order to determine the effect of the 24-epibrassinolide on the germination, seedling growth, leaf area and concentration of chlorophyll under salt stress condition. Seeds were soaked for two hours in water, 100mM NaCl and solutions of 100 mM NaCl supplemented with 24-epibrassinolide at concentrations of 0.01, 0.1 and 1.0 μM. The viability and vigor of rice seeds of cv. BRS Querência were reduced by salinity and were restored by the application of the 24-epibrassinolide in concentration 1.0 μM. While in cv. BRS Bojurú the vigor was reduced by this concentration. The application of the 24-epibrassinolide in cv. BRS Querência increased the concentration of chlorophyll, leaf area, length of root and shoot, fresh and dry mass of root and shoot, reducing the deleterious effects caused by salinity. However, in cv. BRS Bojurú, tolerant to salinity, the application of the 24-epibrassinolide 0.01 μM reversed or did not affect the characteristics of growth, although, concentrations of 0.1 e 1,0 μM reduced the characteristics of growth, but did not affect the chlorophyll concentration. Based on the results, it can be inferred that the supplementation of saline solution with 24-epibrassinolide improves the quality of seed varieties susceptible to salinity, not acting the same way in more tolerant cultivars. / O objetivo da pesquisa foi avaliar a importância do 24-epibrassinolídeo no desempenho fisiológico de sementes de arroz, sendo realizados dois experimentos, em laboratório e casa de vegetação. O primeiro avaliou o desempenho de diferentes concentrações de 24-epibrassinolídeo na qualidade fisiológica de sementes e no crescimento de plântulas de arroz em dois lotes da cv. IRGA 422CL. As sementes de ambos os lotes foram tratadas com concentrações crescentes de 24- epibrassinolídeo (zero; 0,01; 0,1; 0,4 e 1,0 μM), por um período de duas horas e avaliadas por meio dos testes de germinação, primeira contagem da germinação, índice de velocidade de germinação, índice de velocidade de emergência, emergência, comprimento de parte aérea e raiz e massas fresca e seca de parte aérea e raiz. De modo geral em todas as características determinadas, concentrações menores ou iguais a 0,4 μM de 24-epibrassinolídeo produziram respostas positivas na qualidade fisiológica das sementes de arroz cv. IRGA 422CL. O segundo experimento foi conduzido com sementes de arroz de duas cultivares, BRS Querência, genótipo suscetível a salinidade e BRS Bojurú, tolerante ao sal, de modo a determinar o efeito do 24-epibrassinolídeo na germinação, crescimento de plântulas, área foliar e concentração de clorofila em condição de estresse salino. As sementes foram embebidas, por duas horas, em água, NaCl 100 mM e soluções de NaCl 100 mM suplementadas com 24-epibrassinolídeo nas concentrações de 0,01; 0,1 e 1,0 μM. A viabilidade e o vigor das sementes de arroz da cv. BRS Querência, foram reduzidos pela salinidade e restabelecidos pela aplicação do 24- epibrassinolídeo na concentração 1,0 μM. Enquanto, na cv. BRS Bojurú, a aplicação desta concentração reduziu o vigor. Na cv. BRS Querência, suscetível ao sal, a aplicação do 24-epibrassinolídeo incrementou a concentração de clorofila, área foliar, comprimento de raiz e parte aérea, massas fresca e seca de raiz e parte aérea, reduzindo os efeitos deletérios causados pela salinidade. No entanto, na cv. BRS Bojurú, tolerante a salinidade, a aplicação do 24-epibrassinolídeo 0,01 μM reverteu ou não afetou as características de crescimento, porém, concentrações de 0,1 e 1,0 μM reduziram as características de crescimento, mas não afetaram a concentração de clorofila. Com base nos resultados, pode-se inferir que a - x - suplementação da solução salina com 24-epibrassinolídeo melhora a qualidade das sementes de cultivares suscetíveis a salinidade, não atuando da mesma forma em cultivares mais tolerantes.

La recherche analyse l'aspect de la commercialisation du point de vue du petit producteur. Selon le recensement agricole, 80% des exploitations agricoles consacrées à la production de riz ont moins des 20 hectares, ce qui représente 50% de la surface totale occupée dans la production de riz et génèrent 49% de la production totale nationale (Chiriboga, 2008).Les systèmes de commercialisation sont fortement liés aux formes de financement, de sorte que ces mécanismes sont nommés comme un système de négociation institutionnelle qui permet d’entrapercevoir une relation étroite entre les acteurs du financement et de la commercialisation de la production. Dans un tel système institutionnel on observe comment l’acte d’échange va au-delà du terme économique et se crée une structure sociale d’interaction continue et prolongée.De cette façon on peut voir comment l'action économique est encastrée “embbeded” dans le tissu non-économique, les institutions, les relations et ainsi l'échange se produit dans un environnement institutionnalisée. Le système institutionnel est caractérisé par des règles, normes, conventions, la confiance, la réciprocité, le pouvoir et l'inégalité. L'objectif de la thèse est de montrer comment le petit agriculteur fait face à la commercialisation de sa production conditionnés par le financement dans un système institutionnel qui se développe avec les autres acteurs de la chaîne de valeur du riz et déterminer si ce système, caractérisé par un échange économique encastré dans un contexte social non économique, lui génère des bénéfices ou préjudices. / The research analyzes the aspect of commercialization from the small producer perspective. According to the agricultural census, 80% of farms devoted to rice production are under 20 hectares, representing 50% of the total area occupied in rice production and generate 49% of the national total production (Chiriboga, 2008).Marketing systems are strongly linked to forms of financing, so that these mechanisms are named as an institutional trading system that allows to understand the close relationship between the actors that finance along the rice chain. In such an institutional system we observe how the act of exchange goes beyond economic term and creates a social structure of continuous and prolonged interaction.This way we can see how the economic action is embedded in the non-economic relations, institutions, and thus the exchange occurs in an institutionalized environment. The institutional system is characterized by rules, norms, conventions, trust, reciprocity, power and inequality.The aim of the thesis is to show how the small farmer faces the commercialization of its production conditioned by informal funding an institutional system that develops with the other actors in the rice value chain and determine if this system, characterized by the economic exchange in a non-economic social, which can generates benefits or losses to small farmers.

Xanthomonas oryzae pv. oryzae (Xoo), l'agent causal de bactériose vasculaire du riz (BLB), injecte des protéines de liaison à l'ADN, appelées Transcription Activator-Like Effectors (TALEs) dans les cellules hôtes afin de moduler l'expression de gènes cibles. Certains TALEs agissent comme des facteurs de virulence majeurs, indispensables à la mise en place du BLB et ciblent des gènes de sensibilité du riz. Les TALEs majeurs de Xoo ciblent universellement les gènes de sensibilité de la famille SWEET. Il existe dans la nature un polymorphisme des séquences ADN des gènes SWEET reconnues par les TALEs qui confère une résistance à la maladie. L’utilisation de la technologie TALEN a permis d'introduire artificiellement ce type de mutation dans le promoteur du gène de sensibilité SWEET14 le rendant insensible aux TALEs et conférant une résistance à certaines souches de Xoo asiatiques. La caractérisation des populations de Xoo africaines montrent qu'elles sont distinctes de celles d’Asie. L’objectif du projet de thèse était de créer à l'aide des technologies d'édition des génomes des sources de résistances efficaces contre un large panel de Xoo maliennes.Dans une première partie, l'édition des boites ADN de SWEET14 ciblées par des TALEs majeurs de souches africaines a effectivement permis d'obtenir des résistances contre les souches utilisant le TALE TalF (initialement appelé Tal5) mais pas contre celles utilisant TalC. La caractérisation du répertoire de TALEs des souches maliennes par des approches fonctionnelles (sensibilité des lignées éditées, expression de SWEET14 et autres gènes cibles de TALEs) et in silico (séquençage du génome de 8 souches) à révélé une diversité fonctionnelle de ces répertoires et la présence simultanée quasi systématique de versions actives et redondantes de TalF et TalC. La caractérisation de la sensibilité de variétés de riz locales aux souches de Xoo maliennes a montré que ces dernières possèdent un large spectre de virulence et qu'à une exception près, toutes les variétés testées sont sensibles au BLB. L'édition en multiplex par la technique CRISPR/Cas9 des boites TalF et TalC a aboli l'induction de SWEET14 en réponse à une souche malienne. Cependant, les lignées correspondantes sont restées sensibles à cette souche. Dans la dernière partie, pour expliquer ce résultat, nous avons postulé l'existence d'au moins un gène de sensibilité, cible de TalC et redondant avec SWEET14. Une approche bioinformatique a permis d'identifier un locus dont plusieurs caractéristiques en faisaient un candidat intéressant. Ce locus, nommé ATAC (pour Alternative TalC Target) est composé de deux gènes, ATAC1 et ATAC2 induits de façon bidirectionnelle par TalC. Nous avons montré qu'ATAC2, qui code pour un facteur de transcription bHLH atypique potentiellement impliqué dans l’élongation cellulaire et l'immunité chez le riz, se comporte comme un locus de sensibilité lorsqu'il est induit par des TALE artificiels dans un système gain de fonction. Nous avons édité simultanément le promoteur SWEET14 et le locus ATAC. Ces éditions devraient empêcher la reconnaissance du promoteur SWEET14 et du locus ATAC par TalC et TalF afin de conférer une résistance large au BLB au Mali. / Xanthomonas oryzae pv. oryzae (Xoo), the causal agent of bacterial leaf blight of rice (BLB), injects DNA binding proteins called Transcription Activator-Like Effectors (TALEs) into host cells to manipulate plant genes expression. Some TALEs behave as major virulence factors essential for BLB to occur by binding directly to target DNA boxes of rice susceptibility genes and inducing their expression. Xoo major TALEs universally target susceptibility genes of the SWEET family. In nature, polymorphism in the DNA sequence of SWEET genes recognized by TALEs confers resistance to BLB. Using the TALEN technology, this type of mutations has been artificially introduced in the promoter of the SWEET14 susceptibility gene to make it TALE-unresponsive and confer resistance to some Asian Xoo. The characterizations of Malian Xoo populations show that they are distinct from the Asian ones. The PhD project aimed to create broad tailored BLB resistance against Malian Xoo using genome editing technologies.First, editing SWEET14 DNA boxes targeted by major TALEs of African strains indeed yielded resistance against strains relying on TalF (initially named Tal5) but not against those relying on TalC. The characterization of Malian strains TALE repertoires using functional (edited lines susceptibility assays, SWEET14 and other TALE target expression studies) and in silico (genome sequencing of 8 strains) approaches uncovered functional diversity in these repertoires and, the almost systematic, simultaneous presence of active and redundant versions of TalF and TalC. In susceptibility assays of local rice varieties, Malian Xoo strains exhibited a broad virulence spectrum and, with one exception, all tested varieties were susceptible to BLB. Multiplex editing of TalF and TalC target boxes with the CRISPR/Cas9 technology abolished SWEET14 induction in response to a Malian strain. However the corresponding rice lines remained susceptible to this strain. Finally, to explain these results, we postulated the existence of, at least, a TalC target susceptibility gene redundant with SWEET14. Bioinformatics analysis identified a rice locus with several features electing it as a high priority candidate. This locus named ATAC (Alternative TalC Target) is composed of two genes, ATAC1 and ATAC2, bidirectionally upregulated by TalC. We further showed that ATAC2 which is predicted to code for an atypical bHLH transcription factor potentially involved in rice cell elongation and immunity, behaves as a susceptibility gene upon artificial TALEs-mediated induction in a gain of function assay. We used the CRISPR/Cas9 system to simultaneously edit the SWEET14 promoter and the ATAC locus. These mutations should prevent the recognition of the SWEET14 promoter and the ATAC locus by TalC and TalF, compromise their transcriptional induction and ultimately provide broad BLB resistance in Mali.

Le débat à propos de la contribution des chaînes de valeur domestiques à la sécurité alimentaire nationale dans les pays en développement a été ravivé par les dernières crises alimentaires. En Asie, les entreprises du segment intermédiaire réalisent un changement technique et intègrent de nouvelles fonctions, ce qui provoque une augmentation de la valeur ajoutée et un prix de vente au consommateur plus bas. L’objectif général de cette thèse est de contribuer à la connaissance de l’organisation des chaînes de valeur alimentaires domestiques en Afrique et leurs implications économiques et sociales pour les petits producteurs. Elle traite trois questions. Premièrement, la thèse analyse l’organisation de la chaîne de valeur du riz au Sénégal dans le but d’estimer si elle connaît une modernisation similaire à celle observée en Asie. Deuxièmement, la thèse examine l’inclusion des petits producteurs dans l’agriculture contractuelle, avec un intérêt particulier pour la combinaison de modes de commercialisation. Troisièmement, la thèse évalue l’impact des contrats sur les revenus et la sécurité alimentaire des petits producteurs. Le cadre théorique est celui de la gouvernance des Chaînes Globales de Valeur, qui analyse l’influence du pilote de la qualité sur la répartition des tâches et compétences entre les acteurs de la chaîne. Il est combiné avec les cadres théoriques des formes plurielles et des moyens d’existence pour traiter la seconde question. Le cas étudié est celui de la chaîne du riz dans la vallée du fleuve Sénégal. Les analyses de données sont basées sur 154 entretiens qualitatifs et des données quantitatives concernant 913 acteurs de la chaîne de valeur. La participation des producteurs dans les contrats est analysée par un modèle logit multinomial, et le biais de sélection est corrigé avec les modèles de la variable instrumentale et de l’appariement au score de propension. Le premier résultat est que la modernisation de la chaîne de valeur du riz du Sénégal est similaire à celle ayant lieu en Asie. Néanmoins, au Sénégal, (1) la situation de référence est une transaction spot (et non une transaction dans laquelle les intrants et le produit sont liés), et les transformateurs réalisaient la collecte du paddy avant la modernisation, (2) les politiques de crédit contribuent directement au changement de gouvernance et (3) la chaîne de valeur moderne n’est pas compétitive par rapport aux importations de riz brisé. Le second résultat est que les petits producteurs participent aux contrats afin de sécuriser le financement agricole. La segmentation du marché du crédit est liée à l’endettement des petits producteurs auprès de la banque nationale. L’incertitude est un déterminant de second ordre des formes plurielles. De plus, les producteurs commercialisent aussi le paddy par des transactions spots qui peuvent être adaptées aux besoins du ménage. Le troisième résultat est que les impacts des contrats sur les petits producteurs sont différents. Le contrat de commercialisation est un dispositif financier qui n’a pas d’impact sur les pratiques agricoles, les rendements, la qualité du produit et le revenu. Néanmoins, il améliore légèrement la sécurité alimentaire par l’atténuation de la saisonnalité des prix. Le contrat de production a un impact positif sur le revenu des producteurs exclus du crédit bancaire. Néanmoins, il inclut des coûts implicites d’intérêt et d’assurance qui impliquent que ces producteurs obtiennent un profit moins important que celui des producteurs financés par la banque. Dans le but de soutenir la modernisation, les politiques publiques devraient favoriser l’élaboration d’un système d’assurance approprié au crédit agricole. Elles devraient aussi inclure les petits transformateurs dans la modernisation par la promotion de techniques semi-industrielles et l’ouverture de crédit au fonctionnement et à l’équipement. / The debate about the contribution of domestic food chains to national food security in developing countries was revived by the last food price crises. In Asia, midstream enterprises implement technical changes and integrate new functions, resulting in increased added value and lower prices for consumers. The general objective of the thesis is to contribute to knowledge about the organization of domestic food value chains in Africa and their economic and social implications for small-scale farmers. It addresses three issues. First, it analyzes the organization of the rice value chain in Senegal to determine if it follows the same modernization pattern as the Asian one. Second, the thesis examines the inclusion of small-scale producers in contract farming, with a specific focus on the combination of marketing modes. Third, the thesis assesses the impacts of contracts on small-scale farmer incomes and food security. The theoretical framework is the governance of the Global Value Chain, which analyzes the influence of the driver of the quality on the distribution of tasks and skills among the actors of the chain. It is combined with the theoretical frameworks of plural forms and livelihoods to address the second issue. The case studied is the Senegal River Valley rice value chain. Data analyses are based on 154 qualitative interviews and a body of quantitative data involving over 913 actors in the value chain. Producer participation in contracts is analyzed with a multimodal logit model and the selection bias is corrected with instrumental variable and propensity score models. The first result is that modernization of the Senegalese value chain is in step with what is taking place in Asia. Nevertheless, in Senegal, (1) the benchmark situation is a spot transaction (and not a tied output-credit transaction), and processors carried out paddy collection before the modernization, (2) credit policies directly contribute to the change in governance, and (3) the modernization of the rice value chain does not make it competitive relative to imports of broken rice. The second result is that small-scale producers participate in contracts to secure agricultural financing. The segmentation of the credit market is linked to the indebtedness of small-scale producers to the national agriculture bank. Uncertainty is a second order driver towards plural forms. Besides, producers continue marketing through spot transactions which can be adapted to household needs. The third result is that the impacts of contracts on small-scale farmers are different. The marketing contract is a financial device which has no impact on agricultural practices, yields, product quality and income. It nevertheless slightly improves food security by mitigating price seasonality. The production contract has a positive impact on the income of producers who were excluded from bank credit. It nevertheless includes implicit interest and insurance costs, meaning that these producers make less profit than those financed by the bank. In order to support the modernization, policies should enhance the design of an appropriate insurance system for agricultural credit. They should also include small-scale processors in the modernization through the promotion of semi-industrial technics and the opening up of operating and equipment loans. Finally, they should fund studies about the use of small-scale mechanization.

Abstract In this essay I look at the change in the symbolic function of vampires, and to see this I use Bram Stoker’s Dracula and Anne Rice’s The Vampire Lestat. My argument is that the difference between Dracula and Lestat is basically that they represent different ideologies, with Dracula being an imperialist, and Lestat being an anarchist. The difference is shown by taking examples from the text of the two novels, and also taking information about the ideologies, and seeing if the actions and thoughts of the characters match the suggested ideology. First, the essay looks at Dracula and his connection with imperialism, and then it turns to Lestat and his connection with anarchism. The conclusion is that the facts derived from the novels make it quite clear where the political hearts of the vampires lie.

Human exposure to methylmercury (MeHg) through diets (e.g., fish and rice) is a global health concern. Although MeHg exposure through fish consumption has long been considered the major route of mercury health risks, studies concerning the long-term changes in MeHg exposure from fish remain lacking. In sharply contrast to the fish MeHg issue, the presence of MeHg in rice has only been reported recently and its implications on MeHg exposure, albeit probably important, are still in infancy. Focusing on the discrepancies in the studies of MeHg exposure through fish and rice consumption, this study was aimed to assess the MeHg exposure of human infants through consumption of rice cereals and to evaluate the long-term changes in fish MeHg. The presence of MeHg in rice prompted the studies on MeHg concentrations and bioaccessibility in rice cereals and potential infant dietary exposure to MeHg through cereal consumption, which is believed to be the first of its kind. The analysis of a variety of infant cereals sampled from the common markets in the United States and China showed that the concentrations of MeHg in the cereals ranged from 0.07 to 13.9 µg/kg with a mean of 1.61 µg/kg. On the basis of these MeHg concentrations, the daily intake of MeHg through rice cereal consumption for infants was estimated to be 4-122% of the reference dose (RfD). The MeHg bioaccessibility in the cereals, determined using an in vitro digestion method, ranged from 25 to 74% with a mean of 48±16%. A further examination on these results, however, revealed the occurrence of MeHg re-adsorption during extraction steps, which leads to the underestimation of MeHg bioaccessibility and warrants cautions to be exercised when using these procedures to evaluate bioaccessibility in general. The long-term changes in fish MeHg were investigated through conducting a comprehensive data analysis on datasets for the Everglades, a well-studied aquatic ecosystem for Hg contamination. The results showed a clear decline of MeHg in mosquitofish in the Everglades during the past two decades, which was probably related to changes in environmental conditions (e.g., periphyton, dissolve organic matter, and sulfate) instead of mercury deposition.