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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Mapeamento de QTLs para teor de proteína em feijoeirocomum (Phaseolus vulgaris L.) / Mapping QTLs for protein content in common beans (Phaseolus vulgaris L.)

LEÃO, Ariane Castro Mendes 15 December 2006 (has links)
Made available in DSpace on 2014-07-29T15:16:27Z (GMT). No. of bitstreams: 1 Ariane_Castro_Mendes_Leao[1].pdf: 899082 bytes, checksum: 0b19f24baa0e56f0caae9f29a959bb7a (MD5) Previous issue date: 2006-12-15 / The common bean besides being one of the basic meals of brazilian´s population, it is one of the main products that provide protein in the nutritional diet from the society share which is economically less favorable. The identification of molecular markers linked to controlling genes of the protein content in common beans (Phaseolus vulgaris L.) is a very important tool to help breeding programs, raising the efficiency and agility. This way, this work was made with two main goals: a) to map SSR and RAPD markers linked to loci (QTLs) that control protein content in two generations of a segregating population of common beans and b) to compare detection procedures of markers linked to QTLs using the ANOVA method and the process of interval mapping. For that reason, 94 families were taken from the F2 generation and 90 families from the F2:3 generation derived from the cross of genitors CNFC 7812 e CNFC 8056. Results indicated that there is the possibility of identifying molecular markers related to protein content in common beans, utilizing both detection procedures. The ANOVA method identified a greater number of QTLslinked markers than the process of interval mapping in both generations. There was coincidence between the identified loci obtained with the two methods for each generation. Loci that were associated with protein content were different for the F2 and F2:3 generations. However, there was a stable detection of a genomic region of the linkage group 4, indicating a possible role of this region of the common bean genome in the control of seed protein content. The proportion of the trait s phenotypic variation explained by QTLs varied from 5,5% to 9,5%, considering both generation. / O feijão, além de se constituir um dos alimentos básicos da população brasileira, é um dos principais produtos fornecedores de proteína na dieta alimentar dos estratos sociais economicamente menos favorecidos. A identificação de marcadores moleculares ligados a genes controladores de teor de proteína em feijoeiro-comum (Phaseolus vulgaris L.) é uma importante ferramenta para auxiliar os programas de melhoramento, aumentando sua eficiência e agilidade. Desta forma, este trabalho foi realizado com os objetivos: a) mapear marcadores SSR e RAPD ligados aos locos gênicos (QTLs) controladores de teor de proteína em duas gerações de uma população segregante de feijoeiro-comum e b) comparar os processos de detecção dos marcadores ligados aos QTLs utilizando o método de ANOVA e o método de mapeamento por intervalo. Para tanto, foram utilizadas 94 famílias da geração F2 e 90 famílias da geração F2:3 provenientes do cruzamento entre os genitores CNFC 7812 e CNFC 8056. Os resultados mostraram a possibilidade de identificar marcadores moleculares ligados ao teor de proteína em feijoeiro, utilizando ambos os métodos. O método de ANOVA identificou mais marcadores ligados a QTLs do que o processo de mapeamento por intervalo em ambas as gerações. Houve concordância entre os locos identificados pelos dois métodos para cada geração. Os locos que foram associados com o teor de proteína foram distintos para as gerações F2 e F2:3. Entretanto, houve uma detecção estável de uma região genômica do grupo de ligação 4, indicando um possível papel desta região do genoma do feijoeiro no controle do teor de proteína no grão. A proporção da variância fenotípica desta característica explicada pelos QTLs variou de 5,5% a 9,5%, considerando as duas gerações.
42

Identificação de QTLs em soja associados à resistência ao nematoide-das-lesões-radiculares / QTL identification in soybean related to root lesion nematode

José Maurício Terasawa 26 February 2018 (has links)
Soja (Glycine max (L.) Merrill) é uma das mais importantes oleaginosas no mundo e sua relevância pode ser também mensurada pela extensão da sua produção no Brasil, onde representa quase a metade do total da área plantada com grãos. A importância da soja está também associada à multiplicidade de utilização do grão, como por exemplo, na alimentação humana e animal, na indústria química e na geração de energia como biodiesel. A produtividade da soja tem sido frequentemente impactada devido ao ataque de pragas e doenças. Dentre as espécies de fitonematoides, o nematoide-das-lesões-radiculares (Pratylenchus brachyurus Godfrey), tem gerado significativas perdas econômicas aos produtores, variando entre 30 a 50%, dependendo da infestação da cultura. Este trabalho teve como objetivo identificar QTLs (Quantitative Trait Loci), a partir de um conjunto de fenótipos associados à resistência ao nematoide-das-lesões-radiculares utilizando a abordagem de mapeamento multivariado. Uma população de 174 indivíduos F2, obtidos a partir do cruzamento entre duas linhagens de soja FTPG06A e FTPG12X (com baixo fator de reprodução do nematoide), foi utilizada para a obtenção dos valores genéticos preditos (BLUPs - Best Linear Unbiased Predictions) de cinco características estudadas e também para a genotipagem com o SoySNP6k Bead Chip. As características avaliadas foram: fator de reprodução (FR), peso fresco (PA) e comprimento (CA) da parte aérea, peso fresco (PR) e comprimento (CR) da raiz. Um total de 1.240 marcadores SNP (Single Nucleotide Polymorphism) foram mapeados nos 20 grupos de ligação (GLs) da soja. O comprimento total do mapa foi de 3.084,46 centiMorgans (cM), com intervalo médio de 2,54 cM entre marcadores adjacentes. A identificação de QTLs (Quantitative Trait Loci) para os caracteres fenotípicos foi realizada utilizando-se o mapeamento de intervalos múltiplos univariado (MIM) e multivariado (MT-MIM), com estimativa dos efeitos principais dos QTLs e análises de epistasia envolvendo pares de QTLs. Na abordagem MIM foram identificados três QTLs associados à variável CR, nos GLs (Grupos de Ligação) A2 e E (2 QTLs), explicando um total de 34,22% da variação fenotípica dessa variável para a população em estudo. Na abordagem MT-MIM, foram selecionados dois conjuntos de variáveis, de acordo com a correlação entre as mesmas. Três regiões genômicas foram reveladas, sendo estatisticamente significativas para as variáveis CR, FR e CA. A comparação dos seis QTLs identificados no presente estudo com o banco de dados de QTLs do Soybase forneceu evidências de que cinco QTLs, ainda não foram descritos na literatura. Uma busca por sequências candidatas em duas regiões de interesse, associadas à variável FR, foi realizada, com base na plataforma de dados genômicos PlantGDB. Várias sequências candidatas indicam relação com mecanismos importantes na resposta das plantas a estresses bióticos. Dessa forma, os resultados obtidos no presente estudo forneceram informações para auxiliar na melhor compreensão da arquitetura genética dos caracteres quantitativos analisados. / Soybean (Glycine max (L.) Merrill) is one of the most important oil crop worldwide and its relevance can also be measured by the extension of soybean grain production in Brazil, where it represents almost half of the total planting area with grains crops. Importance of soybean is also related to a multiplicity of usage of the grain, for example, in human consumption, animal feed, chemical industry and for energy generation as biofuel. Soybean yield has been frequently reduced by occurrence of pest and diseases. Among phytonematodes species, root lesion nematode (Pratylenchus brachyurus Godfrey) has caused significant economic losses to farmers, ranging from 30 to 50%, depending on crop infestation. This research aimed to identify QTLs (Quantitative Trait Loci), from a set of phenotypes associated with resistance to root lesion nematode, using the multivariate multiple interval mapping. A mapping population of 174 F2 plants derived from a by-parental cross between two soybean breeding lines FTPG06A and FTPG12X (with low nematode reproduction factor), was used for prediction of genetic values (BLUPs - Best Linear Unbiased Predictions) for five traits studied and also for genotyping with SoySNP6k Bead Chip. Traits evaluated were reproduction factor (FR), shoot weight (PA), shoot length (CA), root weight (PR) and root length (CR). A total of 1,240 SNP (Single Nucleotide Polymorphism) markers were mapped into 20 soybean linkage groups (LG). A total map length was 3,084.46 centiMorgans (cM) with an average of 2.54 cM between flanking markers. QTL mapping for those traits was performed using univariate (MIM) and multivariate (MT-MIM) multiple-interval mapping, with main QTL effects estimates and epistasis analysis between QTL pairs. MIM analysis identified three QTLs associated to CR trait at LG A2 and LG E (2 QTL), explaining 34,22% of phenotypic variation estimated for this mapping population. For MT-MIM analysis, two sets of traits were selected, according to the correlation among them. Three genomic regions statistically significant for CR, FR and CA traits were identified. Comparison between six identified QTL and QTL database at Soybase provided evidence that five QTL have not been published yet. Search for candidate sequences located in two regions associated with FR trait were further performed on the PlantGDB genomic data platform. Several candidate sequences indicate relationships with important plant response mechanisms to biotic stresses. Thus, results obtained in the present study provided information to improve knowledge of the genetic architecture of the analyzed quantitative traits.
43

Desequilíbrio de ligação, análise de associação genômica ampla e sinais de seleção em soja / Linkage disequilibrium, genome-wide association analysis and signals of selection on soybean

Maisa Curtolo 02 April 2018 (has links)
Com a disponibilidade de tecnologias de genotipagem robustas, fornecendo milhares de marcadores moleculares a um baixo custo por amostra, tornou-se mais acessível escanear o genoma todo. Logo, as abordagens de mapeamento associativo, baseado no cálculo do desequilíbrio de ligação, e a busca de regiões do genoma que apresentam sinais de seleção foram favorecidas. Essas ferramentas apresentam um grande potencial a ser explorado em programas de melhoramento de soja, auxiliando na obtenção de informações valiosas em relação à arquitetura genética dos caracteres de interesse agronômico e à dinâmica dos processos de seleção. Portanto, os objetivos deste estudo foram: (i) verificar os efeitos da relação genética entre genótipos no desequilíbrio de ligação; (ii) obter informações em relação a arquitetura genética para dez caracteres por meio da abordagem de mapeamento associativo; e (iii) identificar regiões sob seleção diferencial em uma população representada por cultivares brasileiras comparadas a de uma população de genótipos exóticos de diferentes origens geográficas. Para isto, 95 genótipos de soja foram genotipados utilizando a plataforma da Affymettrix (180 K Axiom® Soybean Genotyping Array). O efeito da estrutura populacional sobre DL foi investigado utilizando como correções as matrizes resultantes do software STRUCTURE, DAPC, PCA e a matriz de parentesco. Para o mapeamento associativo, os genótipos foram fenotipados para dez caracteres. Foram realizadasvárias abordagens para detecção de sinais de seleção: estimação da diferenciação populacional nas regiões do genoma por meio do índice de fixção (FST) e cross-population composite likelihood ratio test (XP-CLR); identificação de regiões do genoma com redução de diversidade nucleotídica (μ); e a presença de blocos de haplótipos. Ao utilizar medidas de correções para estimação do DL no genoma da soja observamos a influência da estrutura da população e do parentesco nos padrões de DL. Pelo mapeamento associativo, foram identificados 181 marcadores associados para dez caracteres avaliados em soja. Além disso, foi verificada a complexa interação entre regiões envolvidas no controle de caracteres quantitativos (QTL) e ambientes. Regiões diferencialmente selecionadas foram identificadas entre a população de genótipos brasileiros e de materiais de origens diversas, demonstrando que essas passaram por processos de seleção divergente. / The availability of robust genotyping technologies providing thousands of markers with a low-cost per sample, whole-genome scans are becoming more accessible. Hence, associative mapping approaches, based on the calculation of linkage disequilibrium (LD), and the detection of signals of selection were favored. These tools have a great potential to be explored in soybean breeding programs, helping to obtain valuable information about the genetic architecture of the characters of agronomic interest and of the dynamics of selection processes. Therefore, the objectives of this study were: (i) to verify the effects of the genetic relationship among genotypes on soybean linkage disequilibrium; (ii) to obtain information about the genetic architecture in ten soybean traits with an association mapping approach; and (iii) to identify regions under differential selection between a population represented by Brazilian cultivars compared to a population of exotic genotypes from different geographic origins. For this, 95 soybean genotypes were genotyped using an Affymetrix (180 K Axiom® Soybean Genotyping Array) platform. The effect of the population structure on LD was investigated using as corrections the matrices resulting from the software STRUCTURE, DAPC, PCA and a kinship matrix. We phenotyped ten soybean traits in order to carry the association mapping. Several approaches were carried aiming to detect selection signals: estimation of population genetic differentiation in the genomic regions with fixation index (FST) and cross-population composite likelihood ratio test (XP-CLR); identification of genomic regions with reduced nucleotide diversity (μ); and the presence of haplotype blocks.Using the LD corrections, it was showed the influence of population structure and kinship on LD patterns in soybean. By the association mapping, we identified 181 markers associated with the ten traits evaluated in soybean. In addition, complex interactions between QTL and environments were verified. Differentially selected regions were identified between theBrazilian genotypes population and the population of materials from diverse origins, demonstrating that they underwent divergent selection processes.
44

Identificação de QTLs em soja associados à resistência aos percevejos e a caracteres agronômicos utilizando a abordagem de mapeamento multivariado / QTL identification in soybean related to stink bug resistance and agronomic traits using the multivariate multiple interval mapping approach

Milene Möller 10 April 2017 (has links)
A soja é a cultura agrícola brasileira que mais se expandiu nas últimas três décadas. Atualmente é uma commodity comercializada em larga escala na forma de grão, farelo e óleo. Por ser uma importante fonte de proteína, possui papel fundamental na indústria alimentícia, tanto humana quanto animal. O monocultivo em extensas áreas tem ocasionado o aumento da vulnerabilidade da cultura a patógenos e insetos-praga, com consequências relevantes na produção dos grãos. Dentre tais insetos-praga, os percevejos fitófagos representam um dos grupos de maior relevância para a cultura, pois podem comprometer o rendimento, a qualidade e a sanidade dos grãos. As perdas no rendimento da cultura devido ao ataque por percevejos são superiores a 30%, e o comprometimento no valor germinativo das sementes pode ser superior a 50%. Este trabalho teve como objetivo identificar QTLs (Quantitative Trait Loci), a partir de um conjunto de fenótipos associados à resistência aos percevejos e a caracteres agronômicos, utilizando a abordagem de mapeamento multivariado. Uma população de 228 indivíduos F2, obtida a partir do cruzamento entre as cultivares IAC-100 e CD-215, foi utilizada para a obtenção dos dados genotípicos. Os caracteres agronômicos avaliados na geração F2:3 foram: número de dias para o florescimento (NDF), altura da planta no florescimento (APF), número de dias para a maturidade (NDM), altura da planta na maturidade (APM), acamamento (AC), valor agronômico (VA) e produtividade de grãos (PG). Oito caracteres associados à resistência aos percevejos foram avaliados: período de granação (PEG), retenção foliar (RF), número de vagens por planta (NVP), índice percentual de dano nas vagens (IPDV), número de sementes (NS), peso de cem sementes (PCS), peso de sementes boas (PSB) e peso de sementes manchadas (PSM). O mapa genético obtido, representando os 20 grupos de ligação (GLs) da soja, foi constituído por 417 marcadores SNP (Single Nucleotide Polymorphism), 61 SSR (Simple Sequence Repeat), 30 AFLP (Amplified Fragment Length Polymorphism) e 8 marcadores TRAP (Target Region Amplification Polymorphism). A cobertura do genoma da soja foi de 2.814,82 centiMorgans (cM), com um intervalo médio de 5,46 cM entre marcadores adjacentes. A identificação de QTLs (Quantitative Trait Loci) para os caracteres fenotípicos foi realizada utilizando-se o mapeamento de intervalos múltiplos univariado (MIM) e multivariado (MT-MIM), com estimativa dos efeitos principais dos QTLs. A abordagem MIM revelou um total de 60 QTLs, distribuídos por 13 GLs da soja, sendo 29 QTLs associados a caracteres de resistência aos percevejos e 31 QTLs relacionados a caracteres agronômicos. A percentagem da variação fenotípica explicada pelos QTLs (R2) variou de 14,27% para AC a 65,45% para NDM. Na abordagem MT-MIM, foram selecionados nove conjuntos de variáveis, de acordo com a correlação entre as mesmas. Foram reveladas 20 regiões genômicas distintas, com uma alta tendência de concentração de QTLs em posições similares. No geral, para a maioria das características, os valores marginais de R2 obtidos para os modelos MT-MIM foram superiores em relação aos modelos MIM, variando de 27,98% para APF a 65,30% para NDM. A abordagem MT-MIM permitiu a identificação de 13 novas posições genômicas, com efeito em pelo menos uma das variáveis analisadas, que não foram reveladas nos modelos MIM. Uma comparação com o banco de dados do Soybase forneceu evidências de que muitos QTLs, identificados nesta população em estudo, coincidem com QTLs descritos em outros backgrounds genéticos. No entanto, 56 QTLs identificados no presente estudo ainda não foram descritos na literatura. A maioria dos QTLs identificados explicam, individualmente, até 10% da variação fenotípica das características avaliadas. No entanto, QTLs presentes em oito novas regiões identificadas pela abordagem MT-MIM e oito novos QTLs identificados pela abordagem MIM contribuíram para explicar uma maior percentagem da variação dos fenótipos estudados. Esses QTLs devem ser melhor investigados considerando sua relevância para a seleção simultânea de características de interesse, permitindo uma maior eficiência de seleção e um maior ganho genético. Os resultados obtidos no presente estudo forneceram informações para auxiliar na melhor compreensão da arquitetura genética dos caracteres quantitativos analisados, bem como sobre a relação genética entre os mesmos. / Soybean is the Brazilian crop with the most expansion along the past three decades. Currently, it is a commodity commercialized in large scale as grain, bran and oil. Because it is an important source of protein, it plays a fundamental role in the food industry, both human and animal. Soybean monoculture in large areas has increased crop vulnerability to pathogens and insect pests, with significant consequences on grain production. Among such pest insects, stink bugs are considered a major pest of soybean crop, feeding directly on seeds, reducing yield and seed quality. Losses in crop yield due to stink bugs attack are greater than 30% and seed germination compromising can be greater than 50%. This study aimed to identify QTL (Quantitative Trait Loci), for stink bug resistance traits and agronomic traits using the multivariate multiple interval mapping. An F2 mapping population of 228 plants derived from a biparental cross between IAC-100 and CD-215 was used for genotyping. An F2:3 population was developed to evaluate eight stink bug resistant traits such as graining period, leaf retention, pod number per plant, percentage of pod damage, number of seeds, hundred seed weight, weight of healthy seeds and spotted seed weight. Other seven agronomic traits were evaluated such as number of days to flowering, plant height at flowering, number of days to maturity, plant height at maturity, lodging, agronomic value and grain yield. A total of 417 SNP (Single Nucleotide Polymorphism) markers, 61 SSR (Simple Sequence Repeat), 30 AFLP (Amplified Fragment Length Polymorphism) and 8 TRAP (Target Region Amplification Polymorphism) markers were mapped into 20 soybean linkage groups. The total map length was 2,814.82 cM with an average of 5.46 cM between markers. QTL mapping for those traits was performed using univariate (MIM) and multivariate (MT-MIM) multiple interval mapping, with main QTL effects estimates. MIM analysis identified a total of 60 QTL, through 13 soybean linkage groups, with 29 QTL related to stink bug resistant traits and 31 QTL related to agronomic traits. Phenotypic variation explained by QTL ranged from 14.27% for lodging to 65.45% for number of days to maturity. The traits were divided into nine groups for MT-MIM analysis considering their correlation coefficient. Twenty different genomic regions were identified showing a very high QTL clustering. For most of the traits phenotypic variation estimates for MT-MIM models were higher than MIM models, ranging from 27.98% to 65.30% for plant height at flowering and number of days to maturity, respectively. MT-MIM analysis showed 13 genomic regions controlling at least one of the evaluated traits which were not identified at MIM analysis. Comparison between identified QTL and QTL database at Soybase demonstrated that some QTL were similar to those described in different genetic background. However, 56 QTL detected in the present study were described for the first time in literature. Most of the QTL identified explain, individually, less than 10% of phenotypic variation. However, eight genomic regions identified with MT-MIM analysis and eight QTL identified with MIM analysis explain a great amount of phenotypic variation. These QTL should be investigated considering their importance for simultaneous selection for a high genetic gain. Results obtained in the present study provided information for a better understand of genetics architecture underlying quantitative traits studied and the genetic relation among them.
45

Vliv genotypu na průběh infekce Trypanosoma brucei brucei u myši / Genetic influenceof Trypanosoma brucei brucei infection in mice

Šíma, Matyáš January 2010 (has links)
Genetic influence of Trypanosoma brucei brucei infection in mice The African trypanosomes are zoonotic parasites transmitted by Tse-Tse flies. Two of the three subspecies, Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense, cause sleeping sickness in humans whereas the third subspecies, Trypanosoma brucei brucei is not infective to humans. These parasites are members of Kinetoplastida. Trypanosomes are extracellular parasite witch have complex life cycles involving both insect and mammalian hosts. African trypanosomes after infection penetrate mainly vascularized organs and get into brain where cause serious pathology. Parasite can manipulate with immune system of mammal host in wide spectrum of interactions witch are not clearly understood so far. Discovering of a new immune mechanisms, whitch participite in reaction on african trypanosomes, can reveal some general characteristics of immune system. The results of these studies can help to prepare effective drugs and vaccines against this disease. The best way to observe pathological manifestation and genetical analysis is study on animal models . Study on suitable animal model to find genes which are responsible for control of immune response to T. brucei can help us to find homologous genes in humans. It was found that immune responces to...
46

Desarrollo de líneas de introgresión en melón para la mejora de la calidad de esta especie

Perpiñá Martín, Gorka 27 May 2021 (has links)
[ES] El melón (Cucumis melo L.) es actualmente uno de los cultivos con mayor importancia económica en el mundo. La amplia variabilidad genética intraespecífica que presenta permite el estudio para su explotación del control genético de un amplio abanico de caracteres tanto agronómicos como de calidad del fruto. En los últimos años se han desarrollado un gran número de marcadores moleculares y de herramientas genómicas en melón, que facilitan el desarrollo de nuevas poblaciones de mejora. Las líneas de introgresión (ILs) son un conjunto de líneas que contienen un fragmento cromosómico de un parental donante, normalmente exótico, en un fondo genético común normalmente de una variedad de élite. Estas colecciones son apropiadas para el estudio de caracteres cuantitativos y para la introducción de alelos exóticos favorables en cultivares comerciales. En la presente tesis doctoral se describe el desarrollo de una colección de ILs empleando la entrada japonesa 'Ginsen makuwa', como parental donante y el cultivar francés 'Vedrantais' como parental recurrente. Los sucesivos genotipados en generaciones tempranas mediante la plataforma Agena Bioscience y High Resolution Melting, han mejorado la eficiencia en el proceso de obtención de las ILs (cinco generaciones). Esta colección incluye 27 ILs, que posteriormente se han caracterizado mediante un genotipado de alta densidad (Genotyping by Sequencing). Éstas presentan un promedio de 2,7 introgresiones/IL con un 94% de recuperación del fondo genético 'Vedrantais', representando un 96,8% del genoma donante. El análisis de los datos de fenotipado en tres ambientes y el genotipado dió lugar a la detección de 86 QTLs (Quantitative Tratit Loci), de los que 74 fueron estables en al menos dos ambientes. De éstos, 3 QTLs están relacionados con aspectos de floración, 4 con la precocidad de maduración del fruto, 33 con aspectos morfológicos (forma del fruto, reticulado y espesor de la corteza), 12 con el proceso de maduración (presencia de aroma, capa de abscisión, firmeza de la pulpa), 16 con el color de la pulpa, 5 con el color interno de la corteza y 1 con el contenido en sólidos solubles. Algunos de los QTLs descritos en esta tesis han sido identificados en trabajos previos, lo que da solidez a las regiones detectadas, otros, en cambio, resultan novedosos y, por tanto, muy interesantes, pues constituyen un recurso muy valioso tanto para la búsqueda de genes candidatos como para el empleo de estos alelos en programas de mejora. De entre las ILs más prometedoras, destaca MAK_10-1 por presentar un bloqueo del climaterio, lo cual se traduce en una mayor vida postcosecha, característica muy buscada en el mercado internacional. Los efectos de la introgresión en el cromosoma 10 son la ausencia de aroma externo y la mayor firmeza de la pulpa, además del mayor contenido de sólidos solubles en pulpa. Además, se han localizado varios genes candidatos involucrados en la regulación transcripcional y de señalización de etileno durante la maduración del fruto. Por otro lado, se describen otras líneas potencialmente interesantes, así como genes candidatos, para proporcionar diversidad de tamaños, formas, color de la pulpa y perfil aromático al mercado de tipos cantalupo. Respecto al perfil de compuestos volátiles (VOCs) analizado en las ILs, se encontró que las introgresiones Makuwa en general disminuyeron el contenido en compuestos aromáticos. A pesar del efecto ambiental notable, se pudieron asociar ciertas regiones genómicas a ciertos perfiles de VOCs, identificando a su vez algunos genes candidatos involucrados en diferentes rutas de biosíntesis de aromas. La dificultad de recuperar ciertos perfiles aromáticos en los programas de mejora se pone de manifiesto por el elevado número de regiones y genes implicados, así como por efectos pleiotrópicos que afectan a la producción de aromas y que se describen en esta tesis como el bloqueo del climaterio o / [EN] Melon (Cucumis melo L.) is one of the most economically important crops in the world. The wide intraspecific genetic variability that it presents allows the study of a wide range agronomic and fruit quality traits. In recent years, a large number of molecular markers and genomic tools have been developed in melon, which is a resource that facilitates the development of new breeding populations. Introgression Lines (ILs) are a set of lines that contain a chromosomal fragment of a donor parent, usually wild or exotic, in a common genetic background usually an elite variety. These collections are appropriate for the study of quantitative traits and, above all, for the introduction of exotic alleles in modern cultivars. This doctoral thesis describes the development of a collection of ILs using the Japanese accesion 'Ginsen makuwa', as an exotic donor parent, and the French cultivar 'Vedrantais' as a recurrent parent. Successive genotyping in early generations through the Agena Bioscience platform and High Resolution Melting, have improved efficiency in the process of obtaining ILs (five generations). This collection includes 27 ILs, which have subsequently been characterized by high-density genotyping (Genotyping by Sequencing). These have an average of 2.7 introgressions / IL with a 94% 'Vedrantais' genetic background, representing 96.8% of the donor genome 'Ginsen makuwa'. The analysis of phenotyping data in three environments and genotyping resulted in the detection of 86 QTLs (Quantitative Tratit Loci), of which 74 were stable in at least two environments. Of these, 3 QTLs related with flowering aspects, 33 QTLs related with the mophological fruit (fruit shape, netting and rind thickness), 12 QTLs related with ripening behaviour (presence/absence of aroma, abscission layer and flesh firmness), 16 QTLs were related with flesh color, 5 QTLs related with color of the inner rind and 1 related with the soluble solid concentration. Some of the QTLs described in this thesis have been identified in previous works, giving greater confidence to the detected regions, others, however, are novel and, therefore, very interesting, becouse they constitute a very valuable resource for the search for candidate genes and for the use of these alleles in improvement programs. Of the entire ILs collection, MAK_10-1 presented a blockade of the climacteric, which can translate into a longer post-harvest life, trait that is very in the international market. The effects of introgression on chromosome 10 are the absence of external aroma and the greater flesh firmness, in addition the higher soluble solids content in flesh. In addition, several candidate genes involved in transcriptional regulation and ethylene signaling during fruit ripening have been located. On the other hand, other potentially interesting lines and candidate genes, are described to provide diversity of sizes, shapes, flesh color and aromatic profile to the cantaloupe type market. Regarding the profile of volatile compounds (VOCs) analyzed in ILs, it was found that Makuwa introgressions generally decreased the content of aromatic compounds. Despite the remarkable environmental effect, certain genomic regions could be associated with certain VOCs profiles, identifying some candidate genes involved in different aromatic biosynthetic pathways. The difficulty of recover certain aromatic profiles in breeding programs is evidenced by the high number of regions and genes involved, as well as by pleiotropic effects that affect the aroma production and which are described in this thesis as the blocking of the climacteric or the flesh color due to the presence of carotenes. / [CA] El meló (Cucumis melo L.) és actualment un dels cultius amb major importància económica en el món. La seua gran variabilitat genètica intraespecífica permet l'estudi per a la seua explotació del control genètic d'un gran ventall de caràcters tant agronòmics com de qualitat del fruit. En els últims anys s'han desenvolupat un gran nombre de marcadors moleculars i de ferramentes genòmiques en meló, que faciliten el desenvolupament de noves poblacions de millora. Les línies de introgressió (ILs) són un conjunt de línies que contenen un fragment cromosòmic d'un parental donant, normalment exòtic, en un fons genètic normalment d'una varietat d'èlit. Estes col·leccions són útils per a l'estudi de caràcters quantitatius, a més de per a la introducció d'al·lels exòtics favorables en cultivars comercials. En la present Tesi Doctoral es descriu el desenvolupament d'una col·lecció d'ILs amb l'entrada japonesa 'Ginsen makuwa' com parental donant i el cultivar francés 'Vedrantais' com parental recurrent. Els successius genotipatges en generacions primerenques, mitjançant la plataforma Agena Bioscience i High Resolution Melting, han millorat l'eficiència en el procés d'obtenció de les ILs (cinc generacions). Esta col·lecció inclueix 27 ILs que posteriorment s'han caracteritzat mitjançant genotipatge per seqüenciació. Estes presenten un promedi de 2,7 introgressions/IL amb un 94% de recuperació del fons genètic 'Vedrantais', representant un 96,8% del genoma donant. L'anàlisi de les dades de fenotipatge en tres ambients i el genotipatge, facilità la detecció de 86 QTLs (Quantitative Trait Loci), dels quals 74 foren estables en al menys dos ambients. D'estos, 3 QTLs estan relacionats amb aspectes de floració, 4 amb la precocitat de maduració del fruit, 33 amb aspectes morfològics (forma del fruit, reticulat, espessor pell), 12 amb el procés de maduració (presència d'aroma, capa d'abscisió, fermesa de la polpa), 16 amb el color de la polpa, 5 amb el color intern de la pell i 1 amb el contingut en sòlids solubles. Alguns dels QTLs descrits en la Tesi han sigut identificats en treballs previs, el que dóna solidesa a les regions detectades, altres en canvi, resulten nous i, per tant, molt interessants, ja que constitueixen un recurs valuós tant per a la recerca de gens candidats com per a l'ús d'estos al·lels en programes de millora. D'entre les ILs prometedores, destaca MAK_10-1 per presentar un bloqueig del climateri, el qual es tradueix en una major vida postcollita, característica molt buscada en el mercat internacional. Els efectes de la introgressió en el cromosoma 10 són l'absència d'aroma extern i la major fermesa de la polpa, a més del major contingut en sòlids solubles. S'han localitzat diversos gens candidats involucrats en la regulació transcripcional i de senyalització d'etilè durant la maduració del fruit. Per altra banda, es descriuen altres línies potencialment interessants, així com gens candidats, per a proporcionar diversitat de grandària, forma, color de la polpa i perfil aromàtic al mercat de tipus cantalupo. Respecte al perfil de compostos volàtils (VOCs) analitzat en les ILs, es trobà que les introgressions Makuwa en general van disminuir el contingut en compostos aromàtics. Malgrat el efecte ambiental notable, es pogueren associar certes regions genòmiques a certs perfils de VOCs, identificant alguns gens candidats en diferents rutes de biosíntesis d'aromes. La dificultat de recuperar certs perfils aromàtics en els programes de millora es posa de manifest per l'elevat nombre de regions i gens implicats, així com pels efectes pleiotròpics que afecten a la producció d'aromes i que es descriuen en esta Tesi, com el bloqueig del climateri o la coloració de la polpa per presència de carotens. / Perpiñá Martín, G. (2020). Desarrollo de líneas de introgresión en melón para la mejora de la calidad de esta especie [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/147113 / TESIS
47

Designing Genomic Solutions for Abiotic Traits in Flax (Linum usitatissimum L.)

Khan, Nadeem 15 December 2022 (has links)
Flax (Linum usitatissimum L.) is a self-pollinated crop widely cultivated for fiber and oil production. Flaxseed is renowned for its health attributes but the presence of compounds, such as the heavy metal cadmium (Cd), is undesirable. Genomic studies in flax have produced large amounts of data in the last 15 years, providing useful resources to improve the genetic of this crop using genomics-based technologies and strategies. The goal of this thesis is therefore to capitalize on these advances to address the Cd problem and to propose solutions to improve breeding efficiencies. To find genomic-based solutions to Cd content, to the currently low breeding efficiency and to abiotic stress resistance in flax, this study utilized four major strategies: (1) genomic cross prediction, (2) gene family identification, (3) genome-wide association study (GWAS) and (4) genomic selection (GS). Characterization of the ATP-binding cassette (ABC) transporter and heavy metal associated (HMA) gene families was performed using the flax genome sequence. A total of 198 ABC transporter and 12 HMA genes were identified in the flax genome, of which nine were orthologous to Cd-associated genes in Arabidopsis, rice and maize. A transcriptomic analysis of eight tissues provided some support towards the functional annotation of these genes and confirmed the expression of these ABC transporter and HMA genes in flax seeds and other tissues. A diversity panel of 168 flax accessions was grown in the field at multiple locations and years and the seed content of 24 heavy metals (HMs) was measured. The panel was also sequenced and a single nucleotide polymorphism (SNP) dataset of nearly 43,000 SNPs was defined. A GWAS was conducted using these genotypic and phenotypic data and a total of 355 non-redundant quantitative trait nucleotides (QTNs) were identified for ten of the 24 metal contents. Overall, a total of 24 major and 331 minor effect QTNs were detected, including 11 that were pleiotropic. After allelic tests, 108 non-redundant QTNs were retained for eight of the ten metals and ranging from one for copper (Cu) to 70 for strontium (Sr). A total of 20 candidate genes for HM accumulation were identified at 12 of the 24 major QTN loci, of which five belonged to the ABC transporter family. Many of the metal contents, including Cd, appeared to be controlled by many genes of small effects; hence, GS is better suited than marker-assisted selection for application in breeding. To test this, predictive ability using ten GS statistical models was evaluated using trait-specific QTN and the random genome-wide 43K SNP datasets. Significantly higher predictive abilities were observed from the GS models built with the dataset made of QTNs associated with metal contents (70-80%) compared to that of the 43K dataset (10-25%). This study showed the feasibility of using GS to improve the predictive ability of polygenic traits such as metal content in seeds. GS can be applied in early generation selection to accelerate the improvement of abiotic stress resistance and either select low-Cd lines or discard high-Cd lines. These findings validate the use of a QTL-based strategy as a highly effective method for improving the efficiency of predictive ability of GS for highly complex traits such as resistance or tolerance to HM accumulation. Identification of both large and minor effect QTNs and/or pleiotropic effects hold potential for flax breeding improvement. Candidate gene functional validation can be performed using methods such as genome editing or targeting induced local lesions in genomes (TILLING).
48

Characterization and Enhancement of Genetic Resources for the Improvement of Nutritional and Organoleptic Quality in Solanaceae Vegetable Crops

Rosa Martínez, Elena 26 April 2022 (has links)
Tesis por compendio / [ES] En la presente tesis doctoral nos hemos centrado en estudiar la variabilidad y aportar nuevos recursos útiles para la mejora de la calidad nutricional y organoléptica de los frutos de tomate, berenjena y pimiento, adaptando los cultivos a menores aportes de nitrógeno (N). Para lograr este propósito, llevamos a cabo una caracterización exhaustiva de la composición de los frutos, junto con importantes rasgos agronómicos, de un conjunto de recursos genéticos escasamente explorados hasta la fecha. En el primer capítulo de esta tesis, se llevó a cabo una caracterización exhaustiva de 36 compuestos y parámetros de composición del fruto, que incluían azúcares, ácidos orgánicos, antioxidantes y minerales, en un conjunto de 10 accesiones por cultivo de tomate, pimiento y berenjena, cultivados en las mismas condiciones y prácticas ecológicas. Los resultados mostraron un perfil de composición considerablemente distinto entre las tres especies, principalmente en el perfil antioxidante. Además, se encontró una gran variabilidad dentro de cada especie, lo cual es de interés para la selección de variedades con mejores perfiles nutricionales y organolépticos. En el segundo capítulo de esta tesis, se abordó la caracterización de un conjunto de líneas de introgresión (ILs) de berenjena con Solanum incanum L. como parental donante. El uso de las ILs en la mejora de la berenjena requiere asegurar que los niveles de glicoalcaloides del fruto están por debajo de los límites de seguridad. En un ensayo en dos ambientes, evaluamos 25 rasgos de composición del fruto, incluyendo composición proximal, azúcares, ácidos, compuestos fenólicos, glicoalcaloides y minerales en un conjunto de 16 ILs de berenjena con S. incanum, junto con los padres recurrente y donante, y el híbrido. Los resultados mostraron que los frutos producidos por las ILs eran seguros para el consumo, con una composición similar a la del parental recurrente. También evaluamos un conjunto de 10 de estas ILs, junto con el parental recurrente S. melongena, bajo dos dosis de fertilización de N suministradas con el sistema de riego (8.25 mM de NH4NO3 añadido al agua de riego, y ningún suministro de N externo al agua de riego). Aunque se produjo una limitación significativa en el crecimiento de la planta, en la distribución de N y C, en la carga de frutos y en la materia seca como respuesta a la minimización de los aportes de N, las ILs alcanzaron, en promedio, rendimientos finales similares bajo ambos tratamientos de N, así como produjeron frutos con similar morfología, peso y contenido en compuestos fenólicos. Estos resultados potencian las ILs como materiales de mejora útiles para la adaptación de la berenjena a bajos aportes de N. Gracias a la disponibilidad del genotipado de las ILs de berenjena, las investigaciones realizadas con esta población permitieron identificar varios QTLs asociados a caracteres morfo-agronómicos y de composición del fruto, lo que proporciona nueva información relevante para ampliar el conocimiento genético de la berenjena. En el último capítulo se presenta la primera evaluación de parámetros de calidad de fruto y rendimiento de una colección de 44 variedades del tomate resiliente 'de penjar' bajo dos niveles de fertilización de N (162 kg N ha-1 y 49 kg N ha-1). Se observó una gran variación. La reducción de los aportes de N tuvo un efecto significativo en el hue, cuya media aumentó ligeramente, y en los compuestos y parámetros relacionados con el dulzor, cuya media disminuyó en un 11-16%, mientras que el rendimiento y la mayoría de los rasgos de calidad no se vieron afectados. Estos son resultados prometedores que promueven la conservación del tomate 'de penjar' y a su utilización en programas de mejora. En definitiva, creemos que estos trabajos proporcionarán nuevos recursos fenómicos y genómicos útiles para futuros programas de mejora de las hortalizas de la familia Solanaceae. / [CAT] En la present tesi doctoral ens hem centrat en estudiar la variabilitat i aportar nous recursos útils per a la millora de la qualitat nutricional i organolèptica dels fruits de tomaca, albergínia i pimentó, adaptant els cultius a menors aportacions de nitrogen (N). Per a aconseguir aquest propòsit, duem a terme una caracterització exhaustiva de la composició dels fruits, juntament amb importants trets agronòmics, d'un conjunt de recursos genètics escassament explorats fins hui. En el primer capítol d'aquesta tesi, es va dur a terme una caracterització exhaustiva de 36 compostos i paràmetres de composició del fruit, que incloïen sucres, àcids orgànics, antioxidants i minerals, en un conjunt de 10 accessions per cultiu de tomaca, pimentó i albergínia, cultivats en les mateixes condicions i pràctiques ecològiques. Els resultats van mostrar un perfil de composició considerablement diferent entre les tres espècies, principalment en el perfil antioxidant. A més, es va trobar una gran variabilitat dins de cada espècie, la qual cosa és d'interés per a la selecció de varietats amb millors perfils nutricionals i organolèptics. En el segon capítol d'aquesta tesi, es va abordar la caracterització d'un conjunt de línies de introgressió (ILs) d'albergínia amb Solanum incanum L. com a parental donant. L'ús de les ILs en la millora de l'albergínia requereix assegurar que els nivells de glucoalcaloides del fruit estan per davall dels límits de seguretat. En un assaig en dos ambients, avaluem 25 trets de composició del fruit, incloent composició proximal, sucres, àcids, compostos fenòlics, glucoalcaloides i minerals en un conjunt de 16 ILs d'albergínia amb S. incanum, juntament amb els pares recurrent i donant, i l'híbrid. Els resultats van mostrar que els fruits produïts per les ILs eren segurs per al consum, amb una composició similar a la del parental recurrent. També avaluem un conjunt de 10 d'aquestes ILs, juntament amb el parental recurrent S. melongena, sota dues dosis de fertilització de N subministrades amb el sistema de reg (8.25 mM de NH4NO3 afegit a l'aigua de reg, i cap subministrament de N extern a l'aigua de reg). Encara que es va produir una limitació significativa en el creixement de la planta, en la distribució de N i C, en la càrrega de fruits i en la matèria seca com a resposta a la minimització de les aportacions de N, les ILs van aconseguir, en mitjana, rendiments finals similars sota tots dos tractaments de N, així com van produir fruits amb similar morfologia, pes i contingut en compostos fenòlics. Aquests resultats potencien les ILs com a materials de millora útils per a l'adaptació de l'albergínia a baixes aportacions de N. Gràcies a la disponibilitat del genotipat de les ILs d'albergínia, les investigacions realitzades amb aquesta població van permetre identificar diversos QTLs associats a caràcters morf-agronòmics i de composició del fruit, la qual cosa proporciona nova informació rellevant per a ampliar el coneixement genètic de l'albergínia. En l'últim capítol es presenta la primera avaluació de paràmetres de qualitat de fruit i rendiment d'una col·lecció de 44 varietats de la tomaca resilient 'de penjar' sota dos nivells de fertilització de N (162 kg N ha-1 i 49 kg N ha-1). Es va observar una gran variació. La reducció de les aportacions de N va tindre un efecte significatiu en el hue, la mitjana del qual va augmentar lleugerament, i en els compostos i paràmetres relacionats amb la dolçor, la mitjana de la qual va disminuir en un 11-16%, mentre que el rendiment i la majoria dels trets de qualitat no es van veure afectats. Aquests són resultats prometedors que promouen la conservació de la tomaca 'de penjar' i a la seua utilització en programes de millora. En definitiva, creiem que aquests treballs proporcionaran nous recursos fenòmics i genòmics útils per a futurs programes de millora de les hortalisses de la família Solanaceae. / [EN] In the present doctoral thesis, we have focused on studying the variability and providing new useful resources for the improvement of the nutritional and organoleptic quality of tomato, eggplant and pepper fruits, adapting crops to lower nitrogen (N) inputs. To achieve this purpose, we carried out a comprehensive characterization of fruit composition, together with important agronomic traits, of a set of genetic resources scarcely explored up to date. In the first chapter of this thesis, a comprehensive characterization of 36 compounds and fruit compositional parameters, including sugars, organic acids, antioxidants and minerals, was carried out on a set of 10 accessions per cultivar of tomato, pepper and eggplant, grown under the same organic farming practices. The results showed a considerably different composition profile among the three species, mainly in the antioxidant profile. In addition, a great variability was found within each species, which is of interest for the selection of varieties with better nutritional and organoleptic profiles. In the second chapter of this thesis, the characterization of a set of eggplant introgression lines (ILs) with Solanum incanum L. as the donor parent was addressed. The use of ILs in eggplant breeding requires ensuring that fruit glycoalkaloid levels are below safety limits. In a two-environment trial, we evaluated 25 fruit compositional traits, including proximal composition, sugars, acids, phenolic compounds, glycoalkaloids, and minerals in a set of 16 eggplant ILs with S. incanum, along with the recurrent and donor parents, and the hybrid. The results showed that the fruits produced by the ILs were safe for consumption, with a composition similar to that of the recurrent parent. We also evaluated a set of 10 of these ILs, along with the recurrent parent S. melongena, under two doses of N fertilization supplied with the irrigation system (8.25 mM NH4NO3 added to the irrigation water, and no external N supply to the irrigation water). Although there was a significant limitation in plant growth, N and C distribution, fruit load and dry matter in response to minimized N inputs, the ILs achieved, on average, similar final yields under both N treatments, as well as produced fruits with similar morphology, weight and phenolic content. These results enhance ILs as useful breeding materials for the adaptation of eggplant to low N inputs. Thanks to the availability of genotyping of eggplant ILs, the investigations carried out using this population enabled the identification of several QTLs associated with morpho-agronomic and fruit composition traits, providing new relevant information to expand the genetic knowledge of eggplant. The last chapter presents the first evaluation of fruit quality and yield parameters of a collection of 44 varieties of the resilient tomato 'de penjar' under two levels of N fertilization (162 kg N ha-1 and 49 kg N ha-1). A large variation was observed. Reduced N inputs had a significant effect on hue, whose mean increased slightly, and on sweetness-related compounds and parameters, whose mean decreased by 11-16%, while yield and most quality traits were unaffected. These are promising results that promote the conservation of the 'de penjar' tomato and its use in breeding programs. Ultimately, we believe that this work will provide new phenomic and genomic resources useful for future breeding programs of vegetables of the Solanaceae family. / Elena Rosa Martínez is grateful to the Ministerio de Economía, Industria y Competitividad (MINECO) for a pre-doctoral grant (no. BES-2016-077482), which has funded the doctoral thesis presented herein. This predoctoral grant is part of the research project “Mejora genética de la calidad funcional y aparente de la berenjena”, which has been funded by the Ministerio de Economía, Industria y Competitividad and the European Regional Development Fund (MINECO/FEDER) under grant no. AGL2015- 64755-R. The work presented in this thesis was also undertaken as part of the initiative “Adapting Agriculture to Climate Change: Collecting, Protecting and Preparing Crop Wild Relatives” (http://www.cwrdiversity.org/), which is supported by the Government of Norway and managed by the Global Crop Diversity Trust with the Millennium Seed Bank of the Royal Botanic Gardens, Kew; as part of three European projects, namely, G2PSOL (“Linking genetic resources, genomes and phenotypes of Solanaceous crops”) and BRESOV (“Breeding for resilient, efficient and sustainable organic vegetable production”), which have been funded by the European Union’s Horizon 2020 Research and Innovation Programme under grant agreements no. 677379 and no. 77424, respectively, and SOLNUE (“Tomato and eggplant nitrogen utilization efficiency in Mediterranean environments”), in the framework of the H2020 call SusCrop-ERA-Net; ID#47, which has been funded by the Spanish Agencia Estatal de Investigación under grant agreement no. PCI2019-103375; and finally as part of the national project “Las variedades tradicionales de tomate para el desarrollo de una horticultura biodiversa y sostenible en un contexto de cambio climático”, funded by Generalitat Valenciana (Conselleria d’Innovació, Universitats, Ciència I Societat Digital) under grant agreement no. AICO/2020/042. / Rosa Martínez, E. (2022). Characterization and Enhancement of Genetic Resources for the Improvement of Nutritional and Organoleptic Quality in Solanaceae Vegetable Crops [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/182169 / TESIS / Compendio
49

TOMATO FLESHY FRUIT QUALITY IMPROVEMENT: CHARACTERIZATION OF GENES AND GENOMIC REGIONS ASSOCIATED TO SPECIALIZED METABOLISM IN TOMATO FLESHY FRUIT

Fernández Moreno, Josefina Patricia 18 September 2016 (has links)
Tesis por compendio / [EN] Until recently, the genetic improvement of tomato (Solanum lycopersicum) was focused in agronomic traits, such as yield and biotic or abiotic stresses; therefore the interest in tomato fruit quality is relatively new. The tomato fruit surface can be considered both an agronomic trait as well as a quality trait, because it has an effect on consumer impression in terms of color and glossiness but also it underlies the resistance/sensitivity to cracking or water loss with consequences on fruit manipulation (e.g. transport and processing). The cuticle is deposited over the cell wall surrounding the epidermal cells and it is the first barrier in the plant-environment interface. The cuticle composition includes two main groups of metabolites: cuticular waxes and cutin. Other metabolites can be founded into the cuticle matrix, as triterpenoids and flavonoids. Those minor cuticular components are involved in the correct functionality of the cuticle. Understanding cuticle biosynthesis and genetic regulation requires the development of fast and simple analytical methodologies to study those specialized metabolites using large populations (e.g. mutant collections or introgression lines), together with the identification of genes and genomic regions responsible of their production. This thesis aims to contribute to our understanding of the molecular programs underlying tomato fruit quality by providing: i) a general protocol to profile cuticular waxes in different species, including tomato; ii) a QTL map for cuticular composition (i.e. cuticular waxes and cutin monomers) using the Solanum pennellii introgression line population; iii) a detailed protocol of the reverse genetic tool so-called Fruit-VIGS to assist in the study of gene function in tomato fruit; and iv) a thorough characterization of the first null allele for the transcription factor SlMYB12 (i.e. Slmyb12-pf) in tomato fruit which provides new insights into the regulation of the flavonoid biosynthetic pathway in the fruit peel by high resolution mass spectrometry and RNA-Seq approaches. / [ES] Hasta hace poco, la mejora genética del cultivo del tomate (Solanum lycopersicum) había estado centrada principalmente en caracteres agronómicos, como la productividad y la resistencia a estreses, tanto bióticos como abióticos. Así, el interés en la calidad del fruto de tomate es relativamente reciente. La superficie del fruto del tomate puede considerarse tanto un carácter agronómico como de calidad, pues influye en la primera impresión de los consumidores en términos de color y brillo, así como también en los procesos de resistencia o sensibilidad a la rotura ('cracking') o a la pérdida de agua. Estos factores determinan el aspecto del fruto y condicionan atributos relacionados con su manipulación (transporte y procesado). La cutícula se deposita sobre la pared celular de las células epidérmicas y es la primera barrera que interacciona con el ambiente. Está constituida por dos grandes tipos de metabolitos: las ceras cuticulares y la cutina. Otros metabolitos pueden aparecer embebidos en la matriz cuticular, como es el caso de los triterpenoides y los flavonoides. Estos metabolitos contribuyen a la correcta funcionalidad de la cutícula. La compresión de la biosíntesis y regulación génica de la cutícula requiere del desarrollo de metodologías de análisis sencillas y rápidas para el estudio de estos metabolitos especializados en grandes poblaciones (colecciones de mutantes o líneas de introgresión), así como para la identificación de genes y regiones génicas responsables de la producción y acumulación de dichos compuestos, pudiendo ser muy útiles para implementar programas de mejora de la calidad del tomate. El objetivo de esta tesis es contribuir a la comprensión sobre los programas moleculares subyacentes a la calidad del fruto de tomate, proporcionando: i) un protocolo general de análisis del contenido de ceras cuticulares en diferentes especies, incluyendo el tomate; ii) un mapa de QTL de la composición cuticular (incluyendo ceras y monómeros de cutina) obtenido con la población de líneas de introgresión de Solanum pennellii; iii) un protocolo detallado de uso de la herramienta de genética reversa Fruit-VIGS con el que realizar estudios de funciones génicas en fruto de tomate; y iv) una minuciosa caracterización de un nuevo alelo nulo del factor de transcripción SlMYB12 (Slmyb12-pf) en fruto de tomate, proporcionando nueva información sobre la regulación de la ruta biosintética de los flavonoides en la piel del fruto, utilizando espectrometría de masas de alta resolución y de nuevas tecnologías de secuenciación. / [CA] Fins fa poc de temps, la millora genètica de la tomata (Solanum lycopersicum) anava dirigida fonamentalment als caràcters de tipus agronòmic, com la productivitat i la tolerància a estressos biòtics o abiòtics, resultant que l'interés per la qualitat dels fruits és relativament nou. La superfície de la tomata pot ser considerada tant com un caràcter agronòmic com un de qualitat, ja que és l'aspecte de la superfície del fruit el que confereix al consumidor la primera impressió de color, brillantor, però és també la pell del fruit la responsable de la diferent susceptibilitat del fruit a desenvolupar clevills o que el fruit sofrisca més o menys pèrdues d'aigua, tot tenint importants conseqüències en la manipulació (i.e. transport i processament del fruit). La cutícula és dipositada per sobre de la paret cel·lular que envolta la capa de cèl·lules epidèrmiques i constitueix la primera barrera en la interfase planta-medi ambient. La composició de la cutícula presenta dos grups principals de metabòlits: les ceres i la cutina. També es poden trobar altres metabòlits els triterpenoids i el flavonoids. Aquests darrers components cuticulars menors són implicats en el correcte funcionament de la cutícula. Per tal de comprendre la biosíntesi i la regulació genètica de la cutícula cal desenvolupar tecnologies analítiques senzilles i rapides que permeten estudiar aquests metabòlits especialitzats en poblacions grans de plantes (i.e. Col·leccions de mutants o de línies d'introgressió), a més de la identificació de gens i regions genòmiques que són responsables de la seua producció. Aquesta tesi té com a objectiu contribuir a millorar la nostra comprensió dels programes moleculars que afecten determinats aspectes de la qualitat de la tomata mitjançant els següents objectius: i) proporcionar un protocol general per obtenir perfils de ceres cuticulars en diferents espècies, inclosa la tomata; ii) obtenir un mapa de QTL per a la composició cuticular (i.e. ceres cuticulars i monòmers de cutina) mitjançant la utilització de la població de línies d'introgressió de Solanum pennelli; iii) descriure amb detall el protocol d'una eina de revers genètica denominada Fruit-VIGS que resulta molt adequada per estudiar funció gènica a la tomata; y iv) fer una caracterització exhaustiva del primer al·lel nul del factor de transcripció SlMYB12 (ie. Slmyb12-pf) en tomata la qual proporciona informació nova sobre la regulació de la ruta de biosíntesi de flavonoides en la pell de la tomata mitjançant espectrometria de masses d'alta resolució i RNAseq. / Fernández Moreno, JP. (2015). TOMATO FLESHY FRUIT QUALITY IMPROVEMENT: CHARACTERIZATION OF GENES AND GENOMIC REGIONS ASSOCIATED TO SPECIALIZED METABOLISM IN TOMATO FLESHY FRUIT [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/55505 / TESIS / Premios Extraordinarios de tesis doctorales / Compendio
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Characterization of Corn Fibres for Manufacturing Automotive Plastic Parts

Riaz, Muhammad 04 January 2013 (has links)
The study examined the properties of stalk and cob fibres from recombinant inbred corn lines and their parents, grown at two locations, in a polylactic acid (PLA) matrix. The objectives were to: determine fibre compositions; evaluate the effects of fibres on the functional properties of biocomposites and identify quantitative trait loci (QTLs) and gene markers for fibre performance in biocomposites. Significant Genotype*Location effects were observed. Composites had lower strength (impact, tensile, and flexural) but higher tensile/flexural modulus values than pure PLA. The latter were positively affected by cellulose and hemicellulose but negatively affected by free phenolic levels and 93 fibre QTLs and 62 composite markers were detected. This study identified fibre traits and markers for genes that may be important for the use of corn fibres in biocomposites. / Ontario BioCar Initiative Project funded by Ontario Ministry of Research and Innovation, Agriculture and Agri-Food Canada, The Natural Sciences and Engineering Research Council, The Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) and Ontario Public Sector

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