Self-incompatibility (SI) is an important genetic mechanism to prevent the inbreeding of flowering plants and also an excellent system for studying cell-cell recognition and signal transduction. During evolution, several SI systems have been evolved. A unique SI system widely spreads in the grasses. In the grasses, two unlinked, multi-allelic loci (S and Z) determine SI specificity. A putative self-incompatibility gene (Bm2) was previously cloned. In this study, the role of Bm2 in self-incompatibility was investigated first. The cDNA homologues of Bm2 were sequenced from two pollen-only mutants. The results indicated that Bm2 is not the one of SI genes in Phalaris, but represents a subclass of thioredoxin h. Thus a map-based cloning strategy was then adopted to clone the SI genes from Phalaris. Fine linkage maps of the S and Z regions were constructed. RFLP probes from wheat, barley, oat and rye were screened and the S locus was delimited to 0.26 cM and the Z locus to 1.0 cM from one side using specially designed segregating populations. The S locus was located to the sub-centromere region of triticeae chromosome group 1 and the Z locus to the middle of the long arm of group 2. Finally, barley and rice bacterial artificial chromosome (BAC) clones corresponding to the S and Z region were identified to analyse the chromosome structures and to seek candidate SI genes. The abundant repetitive sequences in the identified barley BAC clones limit their usefulness. Identification of Rice BAC clones orthologous to the S and Z regions open the gate to use rice genome information to clone SI genes from the grasses. A positive rice clone (139.9 kb) orthologous to the S region contained 19 predicted genes. Several of these genes might be involved in pollen tube germination and pollen-stigma interaction, which are the major parts of SI reaction. A positive clone (118.9 kb) orthologous to the Z region gave 16 predicted genes. The predicted genes on the outmost ends of these clones could be used to construct contigs to cover the S and Z regions and delimit the S and Z loci in the grasses. / Thesis (Ph.D.)--Department of Plant Science, 2001.

Self-incompatibility (SI) is an important genetic mechanism to prevent the inbreeding of flowering plants and also an excellent system for studying cell-cell recognition and signal transduction. During evolution, several SI systems have been evolved. A unique SI system widely spreads in the grasses. In the grasses, two unlinked, multi-allelic loci (S and Z) determine SI specificity. A putative self-incompatibility gene (Bm2) was previously cloned. In this study, the role of Bm2 in self-incompatibility was investigated first. The cDNA homologues of Bm2 were sequenced from two pollen-only mutants. The results indicated that Bm2 is not the one of SI genes in Phalaris, but represents a subclass of thioredoxin h. Thus a map-based cloning strategy was then adopted to clone the SI genes from Phalaris. Fine linkage maps of the S and Z regions were constructed. RFLP probes from wheat, barley, oat and rye were screened and the S locus was delimited to 0.26 cM and the Z locus to 1.0 cM from one side using specially designed segregating populations. The S locus was located to the sub-centromere region of triticeae chromosome group 1 and the Z locus to the middle of the long arm of group 2. Finally, barley and rice bacterial artificial chromosome (BAC) clones corresponding to the S and Z region were identified to analyse the chromosome structures and to seek candidate SI genes. The abundant repetitive sequences in the identified barley BAC clones limit their usefulness. Identification of Rice BAC clones orthologous to the S and Z regions open the gate to use rice genome information to clone SI genes from the grasses. A positive rice clone (139.9 kb) orthologous to the S region contained 19 predicted genes. Several of these genes might be involved in pollen tube germination and pollen-stigma interaction, which are the major parts of SI reaction. A positive clone (118.9 kb) orthologous to the Z region gave 16 predicted genes. The predicted genes on the outmost ends of these clones could be used to construct contigs to cover the S and Z regions and delimit the S and Z loci in the grasses. / Thesis (Ph.D.)--Department of Plant Science, 2001.

This essay contains two stories that reflect the reality I face as an educator, as well as a reflective discussion about my self-perceived dilemma. The dilemma reflects a classroom situation where I as an educator have trouble dividing my focus, my focus is either put on entire the class or on the child with special needs. Through this self-perceived situation I have started to question how children with special needs find their place in the school today. I discuss how I can handle and look at the unique situation that occurs when meeting this child. Terms like integration, inclusion, segregation, social rights and the expression "a school for everyone" will be discussed in this text, as well as how we can connect these terms and expressions to the problems I find in the school system’s way of handling children with special needs. I also highlight my dilemma from different ethical perspective. I chose to use Kants duty ethics, Mills utilitarianism (commercial ethics) and Aristotle’s virtue ethics to bring light on my dilemma, but also to find help in my professional role as a leisure pedagogue. The main question my essay deals with is this: How can you, as an educator, have a focus on the class as a whole, but at the same time pay attention to the child with special needs?

The education in Swedish schools today should be for all children. This means that even if a pupil has reading and writing disabilities the education should be in the classroom with the rest of the pupils. The education should include every one. The aim of my study was to investigate the education with pupils that have reading and writing disabilities. I wanted to get a deeper knowledge about working methods that are used for pupils with these problems. In my study I have used qualitative research methods. I have used group interviews and observational studies. In addition to this I have also used informal interviews during the observational studies. One class teacher and one special teacher was interviewed and observed in the study. My results showed that pupils with reading and writing disabilities often were excluded from the classroom during a few lessons per week. The results also showed that the working methods that the class teacher and the special teacher use are different. The class teacher worked with the same working methods for all the children in the class while the special teacher was using the computer as a compensatory aid. For pupils with reading and writing disabilities the work with a computer as a compensatory aid is a motivating working method. The result also showed that cooperation between the class teacher and the special teacher is of great importance.

Made available in DSpace on 2016-12-08T16:44:37Z (GMT). No. of bitstreams: 1 PGPV12MA067.pdf: 824912 bytes, checksum: 361d8ffed5b35ef045437bfc7b0cdc47 (MD5) Previous issue date: 2012-04-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In view of the climate changes that have been intensified, especially water stress, this way, is extremely important to create cultivars that shows greater tolerance to this deficiency. This tolerance is acquired through a dense and deep root system. In this sense the selection of plants with promising root systems in segregating populations is one of the primordial steps in the process of the obtainment in a new cultivar. Another factor with extreme importance is the study of characters of the aerial part with shows the highest correlation with the root system. Thus the objective of this study was to: i) to identify three depths in the soil profile, genotypes in the first segregating generation with higher root system and verify the occurrence of heterosis for the root system. character. ii) identify the phenotypic correlation and yours direct and indirect effects of aerial part characters with the highest correlation with the root distribution, to facilitate the indirect selection for this character. The evaluations were carried out in segregating genotypes (F2) of beans from the crossing in full diallel of the three accessions of the Bean Active Germplasm Bank IMEGEM / UDESC: (BAF 07, BAF 09, BAF 50 and a commercial cultivar IPR Uirapuru). The evaluation of the root system was performed by BOHM (1979) method at three depths (0-10, 10-20 and 20-30 cm) with binary counting form. The components of the aerial part were evaluated when the plants reached the point of harvest. The characters stem diameter, plant height and first pod for having the highest correlation with the root distribution may help in the indirect selection. The low coefficients of determination indicate that the breeder should not be based only on indirect selection for genotypes with higher root system. At the conditions of this work, the selection of plants aiming to increase the root distribution and yield concurrently has not viable, since plants with high production of grains tend to have smaller root distribution. The genotypes measured not present a complete list of your characters, so that indirect selection only by single characters does not guarantee good results in the selection of plants. The propitiate genotypes to the advancement of generations are: two, seven and three for up to 20 cm depth and three for the depth up to 30 cm. The crossing between the parents BAF 07 (black group) and BAF 50 (Rio Group) showed wide genetic diversity, providing a significant increase of the root system in its progenies. The selection of superior genotypes in the 20-30 cm layer is limited because the majority genotypes has a similar distribution and less pronounced. In virtue of the high efect of dominance component occurred heterosis for root distribution in early generations, this could complicate the selection in autogamous species for the character / Tendo em vista as variações climáticas que vem se intensificando, principalmente a deficiência hídrica, é de extrema importância a criação de cultivares que apresentem maior tolerância a esta deficiência. Esta tolerância é adquirida através de um sistema radicular profundo e com melhor distribuição perante a outros genótipos. A seleção de plantas com sistema radicular promissor em populações segregantes é uma das etapas primordiais no processo de obtenção do novo cultivar. Outro fator de extrema importância, é o estudo dos caracteres da parte aérea que apresentam maior correlação com o sistema radicular. Deste modo o objetivo deste trabalho foi: i) identificar em três camadas no perfil do solo, genótipos na primeira geração segregante com sistema radicular superior e verificar a ocorrência da heterose para o caráter sistema radicular. ii) identificar a correlação fenotípica e seus efeitos diretos e indiretos dos caracteres da parte aérea que apresentam maior correlação com a distribuição radicular, visando facilitar a seleção indireta para este caráter. As avaliações foram realizadas em genótipos segregante (F2) de feijão oriundos do cruzamento em dialélo completo de três acessos pertencentes ao Banco Ativo de Germoplasma de Feijão do IMEGEM/UDESC: (BAF 07, BAF 09, BAF 50 e um cultivar comercial IPR Uirapuru). A avaliação do sistema radicular foi realizada pelo método do perfil descrito por (BOHM 1979) em três camadas (0-10; 10-20 e 20-30 cm) com contagem de forma binária. Os componentes da parte aérea foram avaliados quando as plantas atingiram o ponto de colheita. Os caracteres diâmetro do caule, estatura de planta e inserção do primeiro legume por apresentarem as maiores correlações com a distribuição radicular podem auxiliar na seleção indireta. Os baixos coeficientes de determinação indicam que o melhorista não deve basear-se apenas na seleção indireta para obter genótipos com sistema radicular superior. A seleção de plantas visando aumento da distribuição radicular e produção de grãos concomitantemente não se apresenta viável, uma vez que plantas com alta produção de grãos tendem a apresentar menor distribuição radicular. Os genótipo avaliados não apresentam relação completa entre seus caracteres, de maneira que a seleção indireta apenas por caracteres isolados não garante resultados promissores na seleção. Os genótipos propícios para o avanço de gerações são: dois, sete e três para camada até 20 cm e três para a camada até 30 cm. O cruzamento entre os genitores BAF 07 (grupo preto) e BAF 50 (grupo carioca) tem ampla divergência genética, proporcionando incremento significativo do sistema radicular nas suas progênies avaliadas. A seleção de genótipos superiores na camada de 20-30 cm é limitada, pois a maioria dos genótipos apresenta distribuição similar e pouco pronunciado. Em virtude do elevado efeito do componente de dominância ocorreu heterose para a distribuição radicular em gerações iniciais, tal fato pode dificultar a seleção em espécies autógamas para o caráter

<p>This work investigates the assignment of unknown sequences to their species of origin. In particular, I examine four questions: Is existing (GenBank) data reliable for accurate species identification? Does a segregating sites algorithm make accurate species identifications and how does it compare to another Bayesian method? Does broad sampling of reference species improve the information content of reference data? And does an extended model (of the theory of segregating sites) describe the genetic variation in a set of sequences (of a species or population) better? Though we did not find unusually similar between-species sequences in GenBank, there was evidence of unusually divergent within-species sequences, suggesting that caution and a firm understanding of GenBank species should be exercised before utilizing GenBank data. To address challenging identifications resulting from an overlap between within- and between species variation, we introduced a Bayesian treeless statistical assignment method that makes use of segregating sites. Assignments with simulated and <em>Drosophila</em> (fruit fly) sequences show that this method can provide fast, high probability assignments for recently diverged species. To address reference sequences with low information content, the addition of even one broadly sampled reference sequence can increase the number of correct assignments. Finally, an extended theory of segregating sites generates more realistic probability estimates of the genetic variability of a set of sequences. Species are dynamic entities and this work will highlight ideas and methods to address dynamic genetic patterns in species.</p> / Doctor of Philosophy (PhD)

As frutíferas nativas do Brasil são subexploradas comercialmente, sendo que os programas de melhoramento genético são bastante incipientes, devido a muitas limitações associadas à fisiologia e biologia dessas espécies, embora apresentem potencial econômico tanto para o consumo in natura como para o processamento industrial. No Brasil, o maracujá-doce (Passiflora alata) está conquistando novos clientes e mercados, e tem atingido preços até três vezes maiores do que os do maracujá-azedo, amplamente cultivado no país. Os frutos do maracujá-doce são muito apreciados, embora apenas a seleção empírica tenha sido praticada. Evidentemente, seria muito vantajoso obter uma variedade geneticamente superior em termos de qualidade e produção de frutos. Nesse sentido, nosso grupo de pesquisa tem focado esforços visando a caracterizar geneticamente uma população segregante de maracujá-doce. Aqui, foram avaliados 30 genótipos desta população, previamente selecionados como superiores. Estes foram plantados sob três condições experimentais: Anhumas (2014/2015 e 2015/2016) e Piracicaba (2015/2016). Foi utilizado o delineamento em blocos casualizados, sendo que as análises genético-estatísticas tiveram por base a abordagem de modelos mistos para a predição dos valores genéticos (BLUPS). Foram estimados parâmetros genéticos e fenotípicos, herdabilidade, correlações genéticas e resposta esperada à seleção relativamente a peso (PF), comprimento (CF) diâmetro (DF) do fruto, espessura (EC) e peso (PC) da casca, peso (PP) e rendimento de polpa (RP), teor de sólidos solúveis totais (SST) e Produtividade. Os resultados mostraram haver altas correlações genéticas entre os principais atributos do fruto, assim como valores elevados de herdabilidade (desde 0,45 para PF a 0,94 para EC), valores que favorecem a prática de seleção. Em seguida, foi aplicado índice multiplicativo para fins de seleção e seis genótipos foram indicados como superiores, quais sejam: 49, 21, 107, 125, 140 e 122. Nossos resultados devem auxiliar outros estudos e iniciativas de seleção de genótipos mais produtivos, evidenciando a grande utilidade de ferramentas estatísticas modernas para se obter maior resposta à seleção. Em paralelo, foi estudada a resposta do maracujá-doce à infecção causada por Xanthomonas axonopodis. Dois genes, previamente identificados como superexpressos no maracujá-azedo, e que codificam as enzimas lipoxigenase-2 e (+)-neomentol desidrogenase foram aqui analisados via qPCR. No maracujá-doce observou-se maior expressão da (+)-neomentol desidrogenase, enzima associada à resposta de hipersensibilidade. Os sintomas da doença sugerem que a resposta de hipersensibilidade é particular no maracujá-doce, já que ocorre a queda precoce das folhas, evitando a disseminação sistêmica da bactéria. / Brazilian native fruit species are under-exploited commercially, and breeding programs are quite incipient due to many limitations associated with the physiology and biology of these species, although having economic potential both for in natura consumption as well as for industrial processing. In Brazil, the sweet passion fruit (Passiflora alata) is conquering new customers and markets, and has riched up to triple the sour passion fruit prices, widely grown in the country. The fruits of the sweet passion fruit are much appreciated, although only empirical selections have been practiced. Evidently, it would be very beneficial to obtain a genetically superior variety in terms of fruit quality and production. In this scenario, our research group has focused efforts to genetically characterize a segregating population of sweet passion fruit. Here, we evaluated 30 genotypes previously selected from this population by field-cultivating them under three experimental conditions: Anhumas (2014/2015 and 2015/2016) and Piracicaba (2015/2016). A randomized block design was used, and the genetic-statistical analyzes were based on a mixed-effects model approach in order to predict the genetic values (BLUPS). We estimated genetic and phenotypic parameters, as heritability, genetic correlations and expected response to selection for weight (WF), length (LF) diameter (DF) of the fruit, thickness (TS) and weight (WS) of the shell, weight (WP) and pulp yield (PY), total soluble solids (SS) and fruit yield. We found high genetic correlations between the main fruit attributes, as well as high values of heritability (from 0.45 for WF up to 0.94 for TS), values that may favor selection practices. Then, we applied a multiplicative selection index and six superior genotypes were selected, which are: 49, 21, 107, 125, 140 and 122. Our results may assist other studies and initiatives of selection of more productive genotypes, showing the great usefulness of modern statistical tools to obtain greater responses to selection. In parallel, we studied the response of sweet passion fruit to infection caused by Xanthomonas axonopodis. Two genes, previously identified as overexpressed in sour passion fruit, and that encode the enzymes lipoxygenase-2 and (+)-neomentol dehydrogenase were herein analyzed via qPCR. In the sweet passion fruit an increased expression of (+)- neomentol dehydrogenase, an enzyme associated with hypersensitivity response, was observed. The disease symptoms suggest that the response of hypersensitivity is particular in sweet passion fruit, since it provokes the premature fall of the leaves, thereby preventing the systemic bacterial dissemination.

Made available in DSpace on 2014-08-20T14:06:14Z (GMT). No. of bitstreams: 1 Tese_ Igor_ Valerio.pdf: 990885 bytes, checksum: 6b9bd709ded7ec022e6445c220d43a98 (MD5) Previous issue date: 2008-05-20 / Many selection strategies have contributed for the continuous progress in wheat breeding programs. On the other hand, the main yield component (number of fertile tillers), has still been underexploited. In this sense, in order to investigate this issue, this work was planned to report the state of the art processes involved in tiller production and development. This information was crucial to the design of the next experiments on genotypes contrasting for tiller number and their response in segregating generations, when subjected to artificial crosses. The seeding density influences greatly grain yield, since it is directly related to fertile tiller production potential, and has a direct effect on number of ears per unit area. Likewise, the genotype and environment effects were important for the adjustment of seeding density and maximum yield obtained. It is essential that the best seeding rate be found for a given genotype at a given location. Genotypes with reduced tillering potential, revealed a larger buffering effect. However, only at seeding density higher than 400 seeds m-2. The genotypes with high tillering potential revealed the best grain production performance at low seeding density. However, these genotypes have a long developing cycle, with high tillering senescence rate when subjected to high seeding density. The use of genotypes contrasting for tillering ability enabled one to find in the segregating generations, wide genetic variability for tillering ability and consequently for the yield components. The selection for high or low number of tillers and the bulk selection vary their efficiency with the crop management system to which the segregating population is subjected. The best grain yield performance is achieved in the selection for low number of tillers, with high average grain weight under competition. / Diversas estratégias de seleção têm contribuído para o contínuo progresso da cultura do trigo nos programas de melhoramento. Por outro lado, o principal componente do rendimento (número de afilhos férteis), ainda revela severos questionamentos sobre o seu real aproveitamento em condições de lavoura. Neste sentido, por entender a fundamental importância deste assunto, foi buscado neste trabalho, primeiramente, relatar o estado da arte dos processos envolvidos na produção e desenvolvimento de afilhos, o que permitiu trazer, posteriormente, contribuições importantes para o desenvolvimento dos demais trabalhos em genótipos contrastantes para afilhamento e a resposta destes, em gerações segregantes, quando submetidos a cruzamentos artificiais. A densidade de semeadura revela a maior variação na produtividade da cultura, uma vez que está diretamente relacionada ao potencial do genótipo em produzir afilhos férteis, com efeito direto no número de espigas produzidas por unidade de área. Da mesma forma, o efeito do genótipo e do ambiente foram determinantes na densidade de semeadura obtida com o máximo rendimento de grãos, destacando a necessidade de implementar, para cada condição de cultivo e genótipo utilizado, uma densidade ideal. Genótipos com reduzido potencial de afilhamento revelam o maior efeito compensatório, porém, com aproveitamento somente em densidade superior a 400 sementes m-2. Os genótipos com elevado potencial de afilhamento revelam o melhor comportamento para rendimento de grãos em reduzidas densidades, porém, evidenciam um longo ciclo de desenvolvimento, com senescência elevada de afilhos quando submetidos a elevadas densidades. O uso de genótipos contrastantes para o afilhamento, possibilitou encontrar em gerações segregantes, ampla variabilidade genética para o caráter e consequentemente para os componentes do rendimento. A seleção para elevado ou reduzido número de afilhos e a seleção em bulk são dependentes do sistema de manejo em que a população segregante for submetida. O melhor desempenho em rendimento de grãos é alcançado na seleção para reduzido número de afilhos, com média elevada para massa de grãos em competição.

Tesis por compendio / [ES] El cambio climático, impulsado por actividades humanas, intensifica el estrés abiótico en la agricultura, afectando la productividad y la salud del ecosistema. La creciente demanda de productos vegetales expande las tierras agrícolas, empeorando el cambio climático y la desertificación. El estrés por sequía afecta gravemente la productividad de los cultivos, mientras que la fertilización excesiva con nitrógeno altera el ciclo del nitrógeno, causando problemas ambientales y de salud. La berenjena (Solanum melongena L.) es una hortaliza importante, y el uso de recursos genéticos, incluidos los parientes silvestres, es crucial para los programas que buscan mejorar la tolerancia a la sequía y la eficiencia en el uso del nitrógeno. Los avances en secuenciación y genotipado han mejorado nuestra comprensión de los rasgos relacionados con el estrés en los cultivos. Esta tesis doctoral explora el potencial de los parientes silvestres de la berenjena para mejorar la tolerancia a los estreses abióticos. El objetivo es identificar nuevas variaciones genéticas para programas de mejora, centrándose en recursos genéticos, regiones genómicas y genes candidatos para obtener variedades de berenjena más resilientes mediante análisis genómicos, transcriptómicos y fenotípicos. El capítulo I evalúa retrocruzamientos avanzados (ABs) de berenjena y parientes silvestres para mejorar la eficiencia en el uso del nitrógeno (NUE) en condiciones de bajo nitrógeno (N). El estudio de S. elaeagnifolium y los ABs en el fondo genético de la berenjena en condiciones de bajo N reveló diferencias significativas entre los parentales. La alta diversidad fenotípica en los ABs mostró algunos individuos transgresivos con mayores rendimientos y NUE que el parental cultivado. Las evaluaciones de ABs de diferentes bancos genéticos (S. insanum, S. dasyphyllum y S. elaeagnifolium) en condiciones de bajo N destacaron el potencial de estas especies silvestres. La alta diversidad en los ABs respalda el potencial de los parientes silvestres para mejorar la resiliencia de la berenjena bajo estrés abiótico. Los datos de genotipado y fenotipado permitieron la identificación y validación de QTLs para varios rasgos, ampliando la comprensión genómica de la berenjena. El capítulo II investiga los mecanismos de respuesta a la sequía en la berenjena cultivada (S. melongena) y su pariente silvestre S. dasyphyllum. Evaluados en condiciones hidropónicas con concentraciones de polietilenglicol (PEG) en diferentes etapas fenológicas, la secuenciación de ARN (RNA-Seq) analizó los patrones de expresión génica. S. dasyphyllum demostró una tolerancia superior al estrés osmótico en comparación con S. melongena, con más genes diferencialmente expresados (DEGs) bajo estrés. Los análisis de enriquecimiento GO y las vías KEGG revelaron que ambas especies activaron varios factores de transcripción y vías de respuesta al estrés, con S. dasyphyllum mostrando una regulación génica más extensa. Las vías clave incluyeron la señalización de ABA, la señalización de MAPK y varias vías de biosíntesis. Estos resultados destacan el potencial de S. dasyphyllum como fuente genética para desarrollar variedades de berenjena tolerantes a la sequía, enfatizando la importancia de usar parientes silvestres para mejorar la tolerancia de los cultivos. En general, esta tesis doctoral demuestra el potencial de los parientes silvestres de la berenjena para la mejora de la tolerancia a estreses abióticos. El desarrollo de retrocruzamientos avanzados a partir de diferentes parientes silvestres amplió la variación genética, mostrando efectos significativos de las dosis de nitrógeno en varios rasgos e identificando individuos transgresivos con características agronómicas mejoradas. La detección y validación de QTLs proporcionó conocimientos sobre la productividad de la berenjena, la eficiencia en el uso del nitrógeno y los mecanismos de respuesta a la sequía, contribuyendo a variedades de berenjena más sostenibles. / [CA] El canvi climàtic, impulsat per activitats humanes, intensifica l'estrès abiòtic en l'agricultura, afectant la productivitat i la salut de l'ecosistema. La creixent demanda de productes vegetals expandeix les terres agrícoles, empitjorant el canvi climàtic i la desertificació. L'estrès per sequera afecta greument la productivitat dels cultius, mentre que la fertilització excessiva amb nitrogen altera el cicle del nitrogen, causant problemes ambientals i de salut. L'albergínia (Solanum melongena L.) és una hortalissa important, i l'ús de recursos genètics, inclosos els parents silvestres, és crucial per als programes que busquen millorar la tolerància a la sequera i l'eficiència en l'ús del nitrogen. Els avanços en seqüenciació i genotipat han millorat la nostra comprensió dels caràcters relacionats amb l'estrès en els cultius. Aquesta tesi doctoral explora el potencial dels parents silvestres de l'albergínia per a millorar la tolerància als estressos abiòtics. L'objectiu és identificar noves variacions genètiques per a programes de millora, centrant-se en recursos genètics, regions genòmiques i gens candidats per a obtindre varietats d'albergínia més resilients mitjançant anàlisis genòmiques, transcriptòmiques i fenotípiques. El capítol I avalua retrocreuaments avançats (ABs) d'albergínia i parents silvestres per a millorar l'eficiència en l'ús del nitrogen (NUE) en condicions de baix nitrogen (N). L'estudi de S. elaeagnifolium i els ABs en el fons genètic de l'albergínia en condicions de baix N va revelar diferències significatives entre els parentals. L'alta diversitat fenotípica en els ABs va mostrar alguns individus transgressius amb majors rendiments i NUE que el parental cultivat. Les avaluacions d'ABs de diferents bancs genètics (S. insanum, S. dasyphyllum i S. elaeagnifolium) en condicions de baix N van destacar el potencial d'aquestes espècies silvestres. L'alta diversitat en els ABs recolza el potencial dels parents silvestres per a millorar la resiliència de l'albergínia sota estrès abiòtic. Les dades de genotipat i fenotipat van permetre la identificació i validació de QTLs per a diversos caràcters, ampliant la comprensió genòmica de l'albergínia. El capítol II investiga els mecanismes de resposta a la sequera en l'albergínia cultivada (S. melongena) i el seu parent silvestre S. dasyphyllum. Avaluats en condicions hidropòniques amb concentracions de polietilenglicol (PEG) en diferents etapes fenològiques, la seqüenciació d'ARN (RNA-Seq) va analitzar els patrons d'expressió gènica. S. dasyphyllum va demostrar una tolerància superior a l'estrès osmòtic en comparació amb S. melongena, amb més gens diferencialment expressats (DEGs) sota estrès. Les anàlisis d'enriquiment GO i les vies KEGG van revelar que ambdues espècies van activar diversos factors de transcripció i vies de resposta a l'estrès, amb S. dasyphyllum mostrant una regulació gènica més extensa. Les vies clau van incloure la senyalització d'ABA, la senyalització de MAPK i diverses vies de biosíntesi. Aquests resultats destaquen el potencial de S. dasyphyllum com a font genètica per a desenvolupar varietats d'albergínia tolerants a la sequera, emfatitzant la importància d'usar parents silvestres per a millorar la tolerància dels cultius. En general, aquesta tesi doctoral demostra el potencial dels parents silvestres de l'albergínia per a la millora de la tolerància a estressos abiòtics. El desenvolupament de retrocreuaments avançats a partir de diferents parents silvestres va ampliar la variació genètica, mostrant efectes significatius de les dosis de nitrogen en diversos caràcters i identificant individus transgressius amb característiques agronòmiques millorades. La detecció i validació de QTLs va proporcionar coneixements sobre la productivitat de l'albergínia, l'eficiència en l'ús del nitrogen i els mecanismes de resposta a la sequera, contribuint a varietats d'albergínia més sostenibles. / [EN] Climate change, driven by human activities, intensifies abiotic stress in agriculture, impacting productivity and ecosystem health. Rising demands for plant products expand agricultural lands, worsening climate change and desertification. Drought stress severely affects crop productivity, while excessive nitrogen fertilization disrupts the nitrogen cycle, causing environmental and health issues. Eggplant (Solanum melongena L.) is an important vegetable, and using genetic resources, including wild relatives, is crucial for breeding programs aimed at enhancing drought tolerance and nitrogen use efficiency. Advances in sequencing and genotyping have improved our understanding of stress-related traits in crops, supporting resilient cultivar development. This doctoral thesis explores the potential of wild eggplant relatives to improve tolerance to abiotic stresses. The goal is to identify new genetic variations for breeding programs, focusing on valuable genetic resources, genomic regions, and candidate genes for more resilient eggplant varieties through genomic, transcriptomic, and phenotypic analyses. Chapter I evaluates advanced backcrosses (ABs) of eggplant and wild relatives to improve nitrogen use efficiency (NUE) under low nitrogen (N) conditions. The study of S. elaeagnifolium and ABs in the eggplant genetic background under low N conditions revealed significant differences among parentals. High phenotypic diversity in ABs showed some transgressive individuals with higher yields and NUE than the cultivated parent. Evaluations of ABs from different genepools (S. insanum, S. dasyphyllum, and S. elaeagnifolium) under low N conditions highlighted the potential of these wild species for low nitrogen input breeding. Low N conditions decreased chlorophyll content but increased flavonol and anthocyanin levels, reducing aerial biomass, stem diameter, yield, and nitrogen and carbon content in plants and fruits. The high diversity in ABs supports the potential of wild relatives to enhance eggplant resilience under abiotic stress. Genotyping and phenotyping data enabled the identification and validation of QTLs for various traits, expanding the genomic understanding of eggplant. Chapter II investigates drought response mechanisms in cultivated eggplant (S. melongena) and its wild relative S. dasyphyllum. Evaluated under hydroponic conditions with polyethylene glycol (PEG) concentrations (20% and 30%) at different phenological stages, RNA sequencing (RNA-Seq) analyzed gene expression patterns. S. dasyphyllum demonstrated superior tolerance to osmotic stress compared to S. melongena, with more differentially expressed genes (DEGs) under stress. GO enrichment and KEGG pathway analyses revealed that both species activated various transcription factors and stress response pathways, with S. dasyphyllum showing more extensive gene regulation. Key pathways included ABA signaling, MAPK signaling, and various biosynthesis pathways. These findings highlight S. dasyphyllum's potential as a gene source for developing drought-tolerant eggplant varieties, emphasizing the importance of using wild relatives to enhance crop tolerance and sustainability. Overall, this doctoral thesis demonstrates the potential of wild eggplant relatives for breeding tolerance to abiotic stresses. Developing advanced backcrosses from different crop wild relatives expanded genetic variation, showing significant effects of nitrogen doses on various traits and identifying transgressive individuals with improved agronomic characteristics. The detection and validation of QTLs provided insights into eggplant productivity, nitrogen use efficiency, and drought response mechanisms, contributing to more resilient and sustainable eggplant varieties. / Villanueva Párraga, G. (2024). Evaluation of Eggplant, Wild Relatives and Introgression Breeding Materials for Tolerance to Abiotic Stresses [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/209414 / Compendio