Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2017-01-30T17:45:00Z No. of bitstreams: 1 texto completo.pdf: 382121 bytes, checksum: 19aebf930d73168cc2840a57f9eb672c (MD5) / Made available in DSpace on 2017-01-30T17:45:00Z (GMT). No. of bitstreams: 1 texto completo.pdf: 382121 bytes, checksum: 19aebf930d73168cc2840a57f9eb672c (MD5) Previous issue date: 2016-08-16 / O tomateiro é reconhecido como planta modelo para o estudo do desenvolvimento do fruto de outras espécies que possuem anteras com deiscência poricida, sendo esta uma característica que dificulta o processo de polinização. A polinização mecânica é uma prática que facilita a liberação do pólen, melhorando a produção e qualidade dos frutos. Porém, reduzidas informações acerca da eficiência deste tipo de polinização na produção de frutos restringem seu uso. Nesse sentido, o objetivo desta proposta, é estudar os efeitos da polinização mecânica na produção e qualidade de tomates de três grupos varietais comerciais destinados ao consumo in natura em duas épocas de plantio. O experimento foi conduzido em campo, na Unidade de Pesquisa e Extensão de Hortaliças do Departamento de Fitotecnia da Universidade Federal de Viçosa. O delineamento experimental foi o de blocos casualizados, em esquema fatorial 2 (épocas de plantio) x 2 (polinização natural e polinização mecânica). Os ensaios foram realizados em outono/inverno e verão/outono para cada grupo, avaliando-os separadamente. Foram avaliadas variáveis referentes a: produtividade, qualidade, massa seca de sementes e número de sementes. Observou-se aumento na produtividade com o uso da polinização mecânica em ambas épocas de plantio para os grupos varietais Salada e Italiano, enquanto no grupo Santa Cruz apenas verificou-se esse aumento na época de outono/inverno. A polinização mecânica só aumentou o número de sementes no grupo Salada. Independentemente da época de plantio para os grupos varietais Salada e Italiano, a polinização mecânica atua eficientemente aumentando a produção sem alterar a qualidade do tomate. / The tomato plant is recognized as a model to study the development of the fruit of other species that have anther dehiscence poricida with this being a characteristic which complicates the process of pollination. Mechanical pollination is a practice that facilitates the release of pollen, improving production and quality of fruit. However, reduced information about the efficiency of this type of pollination in fruit production restrict its use. In this sense, the objective of this proposal is to study the effects of mechanical pollination on yield and quality of tomatoes three commercial varieties groups intended for fresh consumption in two planting seasons. The experiment was conducted in the field, the Research Unit and Crop Science Department of Horticultural Extension of the Universidade Federal de Viçosa. The experimental design was in casualised blocks in factorial scheme 2 (planting dates) x 2 (natural pollination and mechanical pollination). The tests were carried out in autumn / winter and summer / fall for each group evaluating them separately. Variables were evaluated regarding: productivity, quality, dry seed weight and number of seeds. If you notice an increase in productivity with the use of mechanical pollination in both planting dates for groups Salada and Italiano, while in Santa Cruz group only there was this increase during the autumn/winter. Mechanical pollination only increase the number of seeds in the group Salada. Regardless of the planting season for the groups Salada and Italiano, mechanical pollination operates efficiently increasing production without changing the quality of the tomatoes.

N-acylethanolamines (NAEs) are fatty acid ethanolamides that occur in a wide range of eukaryotes and their composition is specific to species, developmental stage and tissue type. In plants, NAEs negatively regulate growth and mediate stress responses. The function of NAEs is terminated by a highly conserved enzyme fatty acid amide hydrolase (FAAH). In plants, FAAH homologue has been characterized only for model plant Arabidopsis. Under normal growth conditions, AtFAAH overexpressor seedlings showed enhanced growth suggesting that FAAH might act as a modulator of endogenous NAE levels and regulate growth. Because of the significant role NAEs were shown to play in model plant Arabidopsis, it is pertinent to elucidate this conserved metabolic pathway in crop species such as tomato (Solanum lycopersicum) that may lead to improved productivity. We hypothesized that there is a functional FAAH in tomato that hydrolyzes NAEs. With AtFAAH as a template and using BLASTX, we identified two putative FAAH sequences in tomato. CLUSTALW alignment showed conserved amidase signature sequence and the catalytic triad. Molecular visualization system (PyMOL) revealed that the protein structures of putative SlFAAH1and 2 were similar in domain structure to AtFAAH, with minor differences in spatial arrangement. For further biochemical characterization, full-length coding sequence of SlFAAH1 and SlFAAH2 were isolated and cloned into a heterologous expression system. The expressed protein will be characterized for its hydrolytic activity against radiolabelled NAE substrates. This research is expected to lead to characterization of NAE pathway in a crop plant. Long-term implications of this study include development of molecular and biochemical tools necessary to improve tolerance to abiotic stress and increase crop productivity.

No description available.

Tomato (Solanum lycopersicum) is a member of the Solanaceae family. In this research project tomato, more specifically the M82 cultivar was chosen as a model plant for Agrobacterium-mediated gene transfer by cotyledon inoculation. Our objective was to transform tomato with a T-DNA construct bearing a transposon from maize that can be used for mutagenesis when it transposes or moves around the genome of the tomato. The vector used is a two-component in-cis Ac-Ds system which needs a single transformation event. It was proved that it worked in Arabidopsis and rice according to Trijatmiko (2005). The construct consists of the BAR gene conferring resistance to herbicide Basta, hygromycin (HYG) gene conferring resistance to the antibiotic hygromycin and the green fluorescent protein (GFP) gene, which are driven by specific plant promoters. The selectable marker genes such as HYG and BAR were used to select the rare transformation events by making the transformed tomato tissue resistant to the toxic chemicals (antibiotic and herbicide) compared to the untransformed tissue in which growth was inhibited. The results described consist of developing a transformation protocol which enabled the production of transgenic tomato lines by the help of the antibiotic augmetin (amoxicillin/clavulanic acid). The transgenic lines were tested through polymerase chain reaction (PCR) and herbicide bioassays. / Master of Science

La tomate (Solanum lycopersicum) est l’espèce modèle pour l’étude des fruits charnus. Le développement du fruit de tomate a été décrit comme une succession de phases de développement distinctes, dans lesquelles les régulations hormonales jouent un rôle crucial. Afin de mieux comprendre la régulation du développement du fruit de tomate, des approches ciblées sur des catégories particulières de protéines régulatrices (F-Box) ainsi que des approches non ciblées de génomique fonctionnelle ont été menées dans le laboratoire. L'objectif de cette thèse est de contribuer à la validation fonctionnelle de gènes candidats mis en évidence dans ces travaux: trois protéines à F-Box (SlFB2, SlFB11 et SlFB24) et deux facteurs de transcription (SlHAT22 et SlTGA2.1). Au cours de cette thèse, la caractérisation de lignées RNAi précédemment générés pour les protéines SlFB2, SlFB11 et SlFB24 a été poursuivie. Ce travail n’a pas permis pas de conclure sur le rôle de ces protéines à F-Box dans le développement du fruit de tomate. Mais elle a permis d'isoler un mutant d'insertion dans une lignée RNAi SlFB2, spécifiquement affecté au niveau des fruits. Ce mutant est caractérisé par l'absence de développement de tissu loculaire, ce qui entraine une altération de la forme des graines, ainsi qu'une augmentation de la fermeté du fruit. Le site d'insertion de l'ADN-T dans ce mutant n'est pas encore identifié. En outre, la caractérisation des lignées RNAi SlFB11, a permis de proposer l'implication de cette protéine dans la régulation des méristèmes apicaux et floraux. La caractérisation fonctionnelle de SlHAT22 et SlTGA2.1 a été initiée par la génération de lignées transgéniques présentant une altération du niveau d'expression de ces facteurs de transcription (sur-expression et RNAi) ou une altération de la fonction du facteur de transcription par utilisation de la technologie CRES-T. La caractérisation phénotypique des lignées transgéniques, ainsi que des analyses métaboliques préliminaires ont révélé que SlTGA2.1 et SlHAT22 sont impliqués dans des processus de régulation au cours du développement précoce du fruit de tomate. En outre, ils ont également suggéré que SlTGA2.1 est impliqué dans la régulation du murissement du fruit de tomate. / Tomato (Solanum lycopersicum) is a model species for the study of fleshy fruits. Tomato fruit development has been described as a sequence of distinct developmental phases where different hormones play crucial regulatory roles. To further gain insight into the regulation of tomato fruit development, targeted approaches focused on particular classes of regulatory proteins (F-Box) as well as global functional genomics approaches were undertaken in the laboratory. The aim of this thesis was to contribute to the functional validation of candidate genes isolated from such approaches: three F-Box proteins (SlFB2, SlFB11 and SlFB24) and two transcription factors (SlHAT22 and SlTGA2.1).During this PhD thesis, the characterization of SlFB2, SlFB11 and SlFB24 RNAi lines previously generated was pursued. This work does not allow to conclude about the role of these F-Box in tomato fruit development. But it allowed to isolate an insertion mutant in a SlFB2 RNAi line, specifically affected at the fruit level. This mutant is characterized by the absence of locular tissue development and subsequent alteration of seed shape, as well as by an increase in fruit firmness. The insertion site of the T-DNA in this mutant is not yet identified. In addition, characterization of SlFB11 RNAi lines, allowed to propose the implication of this protein in the regulation of the shoot apical and floral meristems.Functional characterization of SlHAT22 and SlTGA2.1 was initiated by the generation of transgenic lines carrying an alteration of the transcription factor (TF) expression level (OE and RNAi lines) or with an alteration of TFs function using the CRES-T technology. Phenotypical characterization of the transgenic lines, together with preliminary metabolic analyses revealed that SlTGA2.1 and SlHAT22 are implicated in regulatory processes during tomato early fruit development. In addition, they also suggested that SlTGA2.1 is involved in the regulation of tomato fruit ripening.

La transformation de la paroi de l’ovaire en un péricarpe charnu implique une coordination entre les divisions cellulaires et l’expansion cellulaire. Des données considérables sur le développement et la maturation du fruit de tomate ont été établies, mais la coordination des divisions cellulaires, de l’expansion cellulaire et de l’endoréduplication durant la mise à fruit ainsi que durant la croissance du fruit de tomate reste grossièrement caractérisée au sein du péricarpe et de nombreuses questions ne sont pas résolues : comment ces deux processus sont-ils régulés et coordonnés durant le développement du fruit d’un point de vue cellulaire? Quand commence l’endoréduplication dans les tissus du fruit et quelle est sa fonction? La première partie de ce mémoire concerne la coordination des divisions cellulaires et de l’expansion cellulaire durant la fin du développement de l’ovaire et le début du développement du fruit. Une différenciation précoce des assises cellulaires composant la paroi de l’ovaire puis le péricarpe a été démontrée. Les divisions cellulaires se font principalement au sein de l’épiderme externe et montrent une synchronisation partielle tandis que l’expansion cellulaire se fait principalement dans le mésocarpe. L’endoréduplication semble être initiée avant l’anthèse. La deuxième partie est consacrée à l’analyse du RNA-seq nucléaire en fonction de quatre niveaux de ploïdie (4, 8, 16 et 32C). La majorité des gènes montrent une augmentation proportionnelle de leurs expressions en fonction des niveaux de ploïdie. Cependant, certains gènes révèlent une surexpression ou une sous-expression en fonction des niveaux de ploïdies. / The transformation of the ovary wall into a fleshy pericarp involves a coordinated pattern of cell division and cell expansion. Considerable data have been reported on tomato fruit development and ripening, but the pattern of cell division, cell expansion and endoreduplication at the tomato fruit set and during fruit growth remains grossly appreciated at the whole pericarp level and many questions are not yet resolved: How are cell division and cell expansion coordinated in tomato fruit a cellular level and according to developmental time? When does endoreduplication begin in fruit tissues and what is its function? The first part of this deals with the coordination of cell division and cell expansion during the end of tomato ovary development and the beginning of fruit growth. Evidence for early differentiation of cell layers in the ovary wall and then in fruit pericarp are presented. Cell division happens mainly in the external epidermis and shows partial synchronization, whereas cell expansion happens mostly in mesocarp cell layers. Endoreduplication is initiated as soon as before anthesis. The second part of this work is devoted to RNA-seq based transcriptome profiling of pericarp nuclei which have been sorted according to four ploidy levels (4, 8, 16 and 32C). We demonstrate that the expression of most of the pericarp-expressed genes shows a proportional increase according to ploidy level, on a nuclear basis. However, a significant amount of genes has been identified as over-expressed or under-expressed according to ploidy level.

Embora o cultivo de tomate seja muito antigo e amplamente distribuído, ainda enfrenta desafios para o melhoramento dos níveis de produção e, da qualidade para o processamento e consumo fresco. A grande maioria das características de interesse agronômico está determinada por loci de caracteres quantitativos (QTL), dificultando ainda mais a identificação e transferência gênica. Diversas características tornam o tomateiro um bom modelo para estudos de dissecação dos determinantes genéticos de QTL. Primeiro, a disponibilidade de fontes de germoplasma selvagens ainda inexploradas que podem aumentar a variabilidade genética, somada à possibilidade de cruzamento entre espécies não simpátricas e à autogamia. Segundo, a grande quantidade de informação genética como mapas, coleções de ESTs, QTL, e populações de mapeamento. Terceiro, o genoma de S. lycopersicum está completamente sequenciado. Por fim, devido a suas diferenças morfogenéticas em relação à espécie modelo Arabidopsis thaliana, o tomate se torna uma alternativa para estudos de eudicotiledonias, principalmente em estudos relacionadas a metabolismo de frutos carnosos. A partir da abundante plataforma de dados disponível e por meio de ferramentas de genômica, e genética reversa, este trabalho aborda o estudo de duas regiões do genoma do tomateiro envolvidas no metabolismo de aminoácidos e na determinação da estrutura da parede celular. O estudo de genômica comparativa de uma região do cromossomo 7 permitiu revelar a perfeita sintenia existente entre S. lycopersicum e a espécies selvagem S. pennellii e estimar o tempo de divergência em 2,7 MAA. Complementarmente, foi possível determinar que as diferenças fenotípicas entre as espécies são maiormente devidas a mudanças nas regiões regulatórias e à presença de SNPs. O estudo funcional do gene LFP (Low Free Putrescine) permitiu caracterizar uma proteína plastidial, até o momento desconhecida em tomateiro, que participa do metabolismo de poliaminas. O silenciamento de LFP resultou na redução da disponibilidade de putrescina livre e no aumento da biomassa vegetativa. Por outro lado, os resultados obtidos do estudo do gene GAUT4 (galacturonosiltransferase 4) demonstraram que a enzima codificada se localiza em Golgi e participa do metabolismo das pectinas. Em frutos, a redução dos níveis de GAUT4 resultou na diminuição de pectina e na alteração da sua composição, porém estes se apresentaram mais firmes. Adicionalmente, o silenciamento do gene GAUT4 modificou o particionamento de açúcares provocando o aumento de massa vegetativa em detrimento do índice de colheita, revelando assim um mecanismo regulatório que comunica o metabolismo da parede celular ao controle da relação fonte-dreno. Desta forma, os resultados obtidos aportam dados fundamentais para a melhor compreensão de caracteres de interesse agronômico, assim como de processos fisiológicos complexos e pouco explorados até o momento no tomateiro / Although tomato is an old and widely distributed culture, it still faces challenges to improve production levels and quality for processing and consumption. The vast majority of agronomical important characteristics are determine by quantitative trait loci (QTL), further hindering the gene identification and transfer. Several features make tomato a good model for studying the genetic determinants underneath QTL. First, the availability of unexploited sources of wild germplasm that can increase genetic variability, coupled with the possibility of interbreeding between no sympatric species and autogamy. Second, the large amount of available genetic information as maps, EST collections, QTL, and an extensive collection of mapping populations. Third, the genome of S. lycopersicum is completely sequenced. Finally, due to their morphogenetic differences in relation to model species Arabidopsis thaliana, tomato becomes an alternative to eudicotyledons studies, especially in studies related to fleshy fruits metabolism. From the abundant data platform available and by means of genomic tools, and reverse genetics, this work addresses the study of two tomato genomic regions involved in amino acids and cell wall metabolisms. The comparative genomic study in a region of chromosome 7 has revealed the perfect synteny between S. lycopersicum and the wild species S. pennellii, and estimated the time of divergence between both species in 2.7 MYA. Additionally, it was possible to determine that the phenotypic differences between species are mostly due to changes in regulatory regions and the presence of SNPs. The functional study of LFP gene (Low Free Putrescine) allowed us to characterize a plastid protein, yet unknown in tomato, which participates in the metabolism of polyamines. The LFP silencing resulted in reduced availability of free putrescine and increased vegetative biomass. Furthermore, the functional characterization of the GAUT4 (galacturonosyltransferase 4) gene demonstrated that the encoded enzyme is located in the Golgi apparatus and participates in the pectin metabolism. In fruits, the reduced levels of GAUT4 resulted in decreased pectin and in the change of its composition. Additionally, GAUT4 gene silencing modified sugars partitioning leading to an increased vegetative biomass together with a drastic reduction of the harvest index. Thus, revealing a regulatory mechanism that communicates the cell wall metabolism to source-sink relationship control. Concluding, the results obtained contribute to a better understanding of agronomical important traits, as well as of complex physiological processes little explored in tomato so far

Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2017-07-05T14:11:03Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação Final.pdf: 2449316 bytes, checksum: 3ddf1827ab91a2c84692f64d9ae89d4b (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-07-11T20:58:59Z (GMT) No. of bitstreams: 2 Dissertação Final.pdf: 2449316 bytes, checksum: 3ddf1827ab91a2c84692f64d9ae89d4b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-07-11T20:58:59Z (GMT). No. of bitstreams: 2 Dissertação Final.pdf: 2449316 bytes, checksum: 3ddf1827ab91a2c84692f64d9ae89d4b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-21 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Os minitomates têm conquistado espaço no mercado devido a sua aptidão para o consumo in natura. No entanto, estudos acerca da melhor forma de condução das plantas, sistemas de cultivo, práticas de manejo e seus efeitos sobre a produtividade, necessidades climáticas, e normas de classificação dos frutos são assuntos a serem esclarecidos. A adoção de técnicas de cultivo de baixo custo e baixo impacto ambiental são preconizadas, e os sistemas de cultivo sem solo com recirculação da solução nutritiva drenada são os mais adequados. Diante disto dois experimentos foram conduzidos em estufa, no Campo Didático do Departamento de Fitotecnia, da Faculdade de Agronomia Eliseu Maciel, da Universidade Federal de Pelotas, nos anos de 2015 e 2016. O primeiro experimento teve como objetivos avaliar o crescimento, o comportamento produtivo e a qualidade de frutos de minitomates dos tipos Grape e Cereja cultivados em dois sistemas fechados de cultivo (vasos e calhas), em substrato de casca de arroz in natura sob diferentes intensidades de desfolha (sem desfolha, uma e duas folhas removidas por simpódio). Também foi realizada a classificação dos frutos por tamanho, empregando-se um grupo de cinco peneiras com perfurações específicas para cada cultivar. O segundo experimento objetivou definir a influência da temperatura e da radiação solar sobre o crescimento das plantas de minitomateiro em estufa em ciclo de outono-inverno, bem como, encontrar o menor valor de radiação solar em que houvesse acúmulo significativo de massa seca pelas plantas. A cultivar Cereja apresentou maior crescimento com acúmulo de massa seca total entre 958 e 1623 g planta-1 , produção entre 7 e 11 kg planta-1 , e tamanho médio de frutos entre 9,7 e 12,0 g. A cultivar Grape acumulou entre 728 e 1015 g planta-1 de massa seca total, teve produção entre 4,62 e 5,84 kg planta-1 , e entre 6 e 7 g fruto-1 de peso médio. Os valores variaram conforme o nível de desfolha. A cultivar Grape apresenta frutos com maior concentração de açúcares, e a retirada de uma folha do simpódio não afeta as respostas produtivas. Entretanto, para cultivar Cereja é necessária a manutenção do simpódio completo. O sistema de cultivo em calhas melhora o crescimento e eleva as respostas produtivas, enquanto que o sistema de vasos aumenta a concentração de açúcares dos frutos. A desfolha diminui a quantidade de frutos classificados como grandes para ambas as cultivares. O sistema de calhas favorece a produção de frutos da cultivar Grape classificados como grandes. As peneiras 1, 2 e 3 são adequadas para a classificação de frutos. É possível classificar frutos de minitomates com o uso de peneiras específicas para cada tipo de fruto. As cultivares apresentam respostas semelhantes à variação da radiação solar e da temperatura. Porém, a cultivar Cereja apresenta maior área foliar e crescimento. A temperatura apresenta influência indireta sobre o metabolismo das plantas, enquanto a radiação solar exerce influência direta sobre todas as variáveis de crescimento. O limiar de radiação solar para as cultivares Cereja e Grape de minitomateiro é de aproximadamente 3,63 MJ m-2 d-1. / Mini tomatoes have gained space in the market due to their flavor for in natura consumption. However, studies on the best way of conducting plants, cropping systems, management practices and their effects on yield, climatic requirements, and fruit grading standards are matters to be clarified. The adoptions of low cost and low environmental impact techniques are recommended, and soilless cropping systems with recirculation of the nutrient solution drained are the most appropriate. Before this, two experiments were conducted in greenhouse, at the Campo Didático do Departamento de Fitotecnia, of Faculdade de Agronomia Eliseu Maciel, in Universidade Federal de Pelotas during 2015 and 2016. The first experiment had as objectives to evaluate the growth, productive behavior and fruit quality of Grape and Cherry mini tomatoes cultivated in two closed growing systems (pots and troughs), in substrate of raw rice husk under different intensities of defoliation (without defoliation, removal of one and two leaves of the sympodium). The classification of fruits by size was also performed, using a group of five sieves with specific drilling for each cultivar. The second experiment aimed to define the influence of temperature and solar radiation on the growth of mini tomato plants in a greenhouse in autumn-winter cycle, as well as to find the lowest value of solar radiation in which there is a significant accumulation of dry matter by the plants. Cherry cultivar presented the highest growth with total dry matter accumulation between 958 and 1623 g plant-1 , production between 7 and 11 kg plant-1 , and mean fruit size between 9.7 and 12.0 g. Grape cultivar accumulated between 728 and 1015 g plant-1 of total dry matter, had production between 4.62 and 5.84 kg plant-1 , and between 6 and 7 g fruit-1 of mean weight. Values varied according to the level of defoliation. Grape cultivar presented fruits with higher sugar concentration, and the removal of one leaf of the sympodium did not affect the productive responses. However, for Cherry cultivar it is necessary to maintain the complete sympodium. The troughs system improved growth and increased productive responses, while the pots growing system increased the sugar concentration of the fruits. Defoliation decreases the amount of fruits grading as large for both cultivars. Troughs system favored the production of Grape cultivars grading as large. Sieves 1, 2 and 3 are suitable for the grading of fruits. It is possible to grading fruits of mini tomatoes with the use of specific sieves for each type of fruit. Cultivars presented responses similar to the variation of solar radiation and temperature. However, Cherry cultivar presented greater leaf area and growth. The temperature had an indirect influence on the plant metabolism, while the solar radiation exerted a direct influence on all the growth variables. The solar radiation threshold for cultivars Cherry and Grape of mini tomato plant is around 3.63 MJ m-2 d-1.

Dans un contexte de limitation de l'utilisation des pesticides, une voie de recherche prometteuse porte sur le déterminisme environnemental actionnant les mécanismes de défense de la plante, entre autres, la production de métabolites secondaires. L'objectif de mon travail de thèse a été d'étudier le compromis entre croissance et défense (métabolisme primaire vs. secondaire) dans les tissus de la plante saine ou attaquée par différents bioagresseurs, sous différentes conditions de disponibilité en ressources. Pour cela, nous avons mesuré différents paramètres de croissance, les ratios C/N des tissus, les concentrations en principaux métabolites primaires (glucides simples, amidon) et en composés de défense (acide chlorogénique, rutine, kaempferol-rutinoside et tomatine) dans différents organes de tomate en culture hydroponique en serre ou phytotron. Nous avons observé que les variations des ratios C/N total et de ressources sont positivement corrélées à celles de nombreux composés de défense quelle que soit leur composition en N et C. De plus, nous avons montré qu'en présence d'un bioagresseur, les concentrations des composés primaires et secondaires ne suivent pas la même évolution selon leur nature. La synthèse de caffeoyl putrescine est fortement induite lors de l'attaque par P. syringae alors que la concentration en acide chlorogénique est diminuée. L'inoculation de P. syringae réduit les concentrations en glucose et fructose alors que P. corrugata stimule leur synthèse. Enfin, nous avons observé qu'une faible disponibilité en azote altère le développement de P. syringae, P. corrugata et Tuta absoluta mais favorise le développement de Botrytis cinerea. Nos résultats ont montré que le ratio C/N est un indicateur fiable du compromis croissance/défense dans le cas d'une plante saine. Dans le cas d'une plante attaquée, la répartition des ressources entre les différents métabolites varie en fonction du bioagresseur. Et chaque bioagresseur réagit de façon différente aux variations de disponibilité en azote de la plante. La maîtrise des conditions de culture apparaît comme un levier agronomique pertinent pour raisonner la lutte contre les bioagresseurs même s'il est difficile d'appliquer des règles générales sur l'interaction plante/environnement/bioagresseurs / Nowadays, limiting the use of pesticides is mandatory. A promising way for research deals with the environmental determinism of plant defence mechanisms, among others, production of secondary metabolites. The aim of my PhD work was to study the trade-off between growth and defence (primary vs. secondary metabolism) in healthy plant tissues or attacked by different pests, under different conditions of resources availabilities. We measured different growth parameters, C:N ratios of tissue, concentrations of main primary metabolites (simple carbohydrates, starch) and defence metabolites (chlorogenic acid, rutin, kaempferol-rutinoside and tomatine) on healthy or attacked tomato plant grown in hydroponic culture in greenhouse or phytotron. We observed that variations of total and resources C:N ratios were positively correlated to that of several defence compounds whatever their composition in carbon and nitrogen. Moreover, we showed that, during pests attack, concentrations of primary and secondary metabolites did not follow the same evolution, depending on their nature. Caffeoyl putrescine synthesis was strongly induced by P. syringae inoculation whereas chlorogenic acid concentration decreased. Inoculation of P. syringae induced a strong decrease of concentration of glucose and fructose whereas inoculation of P. corrugata enhanced their synthesis. We observed that a low N availability alters the development of P. syringae, P. corrugata and Tuta absoluta but promotes the development of B. cinerea. Our results showed that C:N ratio is a reliable indicator of the trade-off between growth and defence in the case of healthy plant. In attacked plant, the resources allocation between different metabolites varies with pests. And each pests reacts specifically to changes of N availability for the plant. Control of culture conditions appears to be a relevant agronomic tool to monitor the control of pests even if it is difficult to apply general rules to the interaction plant/environment/pests

Made available in DSpace on 2017-07-10T17:37:38Z (GMT). No. of bitstreams: 1 Juliana_de_Jesus_Silva_Davi.pdf: 2712919 bytes, checksum: 9af947f2bdd1f277be5274ffa0e2819e (MD5) Previous issue date: 2010-06-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of this study was to evaluate the effect of four plant spacing, associated with four systems of tip pruning, yield and quality of tomato fruit in the system of organic production in protected environment. The experiment was conducted in a protected environment, in the Sector of Organic Culture of the Experimental Station Prof. Dr. Antonio Carlos dos Santos Pessoa of the Universidade Estadual do Oeste do Paraná (UNIOESTE), in the city of Marechal Cândido Rondon-PR, in the period November of 2008 until April of 2009. The experiment was arranged in a randomized block, in project of parcels split-split plot design in the space, with four repetitions. The treatments had been constituted by the combination of four plant spacing (0,2, 0,3, 0,4 and 0,5 m), in the plot, with four tip pruning (3, 4, 5 and 6 clusters for plant), in split plot , and six clusters (1, 2, 3, 4, 5 and 6 clusters in the plant), in split-split plot. The seedlings of the hybrid of tomato Alambra were transplanted on the 26th day after the sowing (DAS). The harvest began at 64 th days after transplanting (DAT) and finished on 119 th DAT. The following parameters were evaluated: fruit mass marketable and total for plant, fruit number marketable and total for plant, fruit individual mass marketable and total, fruit yield marketable and total, longitudinal diameter of normal fruits, transversal diameter of normal fruits, percentage of abnormal fruits, soluble solid text, pH, titratable acidity, height of plants and stem diameter. The data were subjected to analysis of variance of linear models to verify the significance of the effects of plant spacing, tip pruning, cluster and their interactions. Considering the conditions where the experiment was developed it can conclude that the fruits of the first clusters of the plant have a higher mass of fruit, independent of the tip pruning and adopted spacing; the tip pruning after the third cluster reduces marketable yield of tomato fruits, the plant spacing of 0,2 and 0.3 m provide higher total yield, and the tip pruning and planting density have a variable effect on fruit quality of tomato / O presente trabalho teve como objetivo principal avaliar o efeito de quatro espaçamentos entre plantas, associados a quatro sistemas de poda apical, na produtividade e qualidade dos frutos de tomateiro, no sistema de produção orgânica, sob cultivo protegido. O experimento foi conduzido em ambiente protegido, no Setor de Cultivo Orgânico da Estação Experimental Prof. Dr. Antônio Carlos dos Santos Pessoa, da Universidade Estadual do Oeste do Paraná, no Município de Marechal Cândido Rondon-PR, no período novembro de 2008 a abril de 2009. O experimento foi conduzido em delineamento de blocos casualizados, em esquema de parcelas subsubdivididas no espaço, com quatro repetições. Os tratamentos foram constituídos pela combinação de quatro espaçamentos entre plantas (0,2, 0,3, 0,4 e 0,5 m), na parcela, com quatro podas apicais (3, 4, 5 e 6 cachos por planta), na subparcela, e seis cachos (1, 2, 3, 4, 5 e 6 cachos na planta), na subsubparcela. As mudas da cultivar Alambra foram transplantadas aos 26 dias após a semeadura (DAS). A colheita iniciouse aos 64 dias após o transplantio (DAT) e terminou aos 119 DAT. Foram avaliadas as seguintes variáveis: massa de fruto comerciável e total por planta, número de fruto comerciável e total por planta, massa individual de fruto comerciável e total, produtividade de fruto comerciável e total, diâmetro longitudinal de frutos normais, diâmetro transversal de frutos normais, porcentagem de frutos anormais, teor de sólidos solúveis, pH, acidez titulável, altura de plantas e diâmetro de caule. Os dados foram submetidos à análise de variância de modelos lineares para verificação da significância dos efeitos de espaçamento entre plantas, poda apical, cacho e suas respectivas interações. Considerando as condições em que o experimento foi desenvolvido pode se concluir que os frutos dos primeiros cachos da planta apresentam maior massa de frutos, independente da poda apical e espaçamento entre plantas adotado; a poda apical após o terceiro cacho reduz a produtividade comercial de frutos de tomateiro; os espaçamentos de 0,2 e 0,3 m entre plantas proporcionam maior produtividade total, e a poda apical e a densidade de plantio possuem efeito variável sobre a qualidade dos frutos do tomateiro