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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.
161

Détection de QTL d’expression de protéines de foie gras de canard mulard / Detection of protein expression QTL of mule duck “foie gras”

François, Yoannah, Coralie, Stéphanie 21 October 2014 (has links)
L’objectif de ce projet était de comprendre comment l’expression du génome influence les caractères de qualité du foie gras, tels que le poids de foie, le taux de fonte et les teneurs, en lipides et protéines, et d’identifier les mécanismes moléculaires sous-jacents. Afin de répondre à ces objectifs, nous avons dans un premier temps étudié l’expression différentielle de protéines selon les phénotypes des foies des canards mulards puis dans un second temps, nous avons entrepris d’identifier des QTL phénotypiques et protéiques (pQTL) à l’aide d’une nouvelle carte génétique composée de marqueurs SNP et microsatellites. Tout d’abord, une optimisation du dispositif expérimental a été entreprise : 3 famille F1, composées de 98 canes backcross et de leurs 294 fils mulards ont été sélectionnés pour leur contribution à des QTL existants liés à la qualité du foie gras. La première approche nous a permis de montrer que les foies ont des profils protéiques et métaboliques différents selon leur phénotype. Ainsi, les foies légers qui fondent peu, avec une faible teneur en lipides mais une forte teneur en protéines présentent un processus anabolique par la surexpression de protéines impliquées dans les métabolismes lipidiques, glucidiques, de synthèse. Au contraire, les foies lourds, fondant beaucoup, avec une forte teneur en lipides mais une faible teneur en protéines présentent des mécanismes de cytoprotection et de réponse au stress. La seconde approche nous a permis de mettre en évidence 30 QTL relatifs à des phénotypes de qualité du foie gras et 50 pQTL relatifs à différentes protéines. Sept chromosomes se démarquent par la ségrégation de plusieurs QTL et pQTL permettant d’émettre des hypothèses quant aux fonctions des gènes sous-jacents à ces QTL. Entre autres, le locus d’APL15 semble lié à la glycolyse et celui d’APL18 à des processus de survie cellulaire. L’ensemble de ces résultats permet ainsi non seulement d’identifier les voies métaboliques impliquées dans la qualité du foie, mais également d’établir un lien entre les caractères, les protéines et les loci des QTL suggérant un déterminisme génétique de ces voies métaboliques impliquées. Ces relations nécessitent d’être approfondies afin de préciser les processus et les gènes impliqués dans la qualité du foie gras. / The aim of this project was to understand how the genome expression influences liver quality traits such as liver weight, melting rate, lipid and protein rates, and to identify the molecular mechanisms underlying it. First, we studied the differential expression of proteins according to liver quality traits of mule ducks. Then we carried out detections of uni-trait and multi-traits phenotypic QTL and protein QTL using a new genetic map containing SNP and microsatellite markers. In preamble to the study, the optimization of the experimental disposal was necessary: 98 backcross dams and their 294 mule sons, composing 3 F1 families were selected because of their contribution to the likelihood of existing QTL related to foie gras quality. The first study showed that livers presented different protein and metabolic profiles according to their phenotypes. Indeed, light livers, with low melting rate, low lipid rate and high protein rate show an over-expression of proteins involved in lipid, glucid or in synthesis metabolism, suggesting an anabolism process. On the contrary, heavy livers, with high melting rate, high lipid rate and low protein rate show cytoprotection and response to stress mechanisms. The second study highlighted 30 QTL related to liver quality traits and 50 pQTL related to different proteins. In particular, 7 chromosomes segregated several QTL and pQTL, permitting to assess hypothesis on the functions of the genes underlying these QTL regions. As an example, the APL15 locus seems linked to glycolysis and the APL18 one seems linked to cell survival ones. All these results helped in identifying metabolic pathways implicated in liver quality as well as establishing a link between traits, proteins and the QTL loci, suggesting a genetic determinism of these pathways. These relationships need to be further studied in order to bring precision to the process and to determine more precisely the genes implicated in the foie gras quality traits.
162

IdentificaÃÃo de QTLs candidatos associados à qualidade pÃs-colheita do pedÃnculo de caju / Detection of candidate QTLs associated the postharvest quality of cashew apple

Francisco Herbeth Costa dos Santos 30 May 2008 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A identificaÃÃo de locos que controlam caracterÃsticas quantitativas (QTLs), e a seleÃÃo assistida por marcadores moleculares associados a esses QTLs, tem despertado grande interesse em programas de melhoramento visando à qualidade dos frutos. Objetivou-se com este estudo avaliar a qualidade de cajus em genÃtipos de cajueiro e identificar QTLs candidatos relacionados com estes caracteres, utilizando os mapas genÃticos jà desenvolvidos para o cajueiro. Para as anÃlises fÃsicas e fÃsico-quÃmicas foram coletados quinze cajus/planta em 66 plantas da geraÃÃo F1 originada do cruzamento CCP 1001 x CP 96 e no clone CCP 76, utilizado como testemunha. Foram avaliadas as seguintes caracterÃsticas: coloraÃÃo (luminosidade, intensidade de vermelho e amarelo), pesos (total, castanha e pedÃnculo), tamanho (comprimento, diÃmetros basal e apical), fenÃlicos oligomÃricos, sÃlidos solÃveis totais, acidez total titulÃvel, doÃura e vitamina C. Para identificaÃÃo dos QTLs candidatos foram utilizadas as metodologias de mapeamento nÃo paramÃtrico, mapeamento de intervalo e mapeamento de QTLs mÃltiplos. Os resultados demonstraram elevada variaÃÃo fenotÃpica na geraÃÃo F1 para todos os caracteres em estudo, com potencial para seleÃÃo de genÃtipos que atendam as exigÃncias do mercado in natura. As anÃlises de QTLs permitiram a identificaÃÃo de 54 QTLs associados a qualidade do pedÃnculo. O carÃter que apresentou o menor nÃmero de QTLs foi intensidade de vermelho, com dois, e o que apresentou o maior nÃmero foi o peso do pedÃnculo, com sete. Estes QTLs explicaram entre 3,15 % e 21,33 % da variaÃÃo fenotÃpica total. Os resultados obtidos suportam fortemente a presenÃa de QTLs verdadeiros. Estes QTLs estÃo em processo de validaÃÃo para que possam ser utilizados na seleÃÃo assistida por marcadores em programas de melhoramento genÃtico do cajueiro. / Detection of quantitative trait loci (QTLs) and marker assisted selection associated with theses QTLs have shown a great interest in breeding programs focused on fruit quality traits. The aim of this work were to study the quality of cashew apple in several genotypes and identify QTLs associated with these traits, using the cashew genetic maps already developed. For the physical and physical-chemical analyses, it was collected 15 cashew apple per plant, from 66 genotypes of the generation F1 originated from the cross CCP 1001 x CP 96 and from the clone CCP 76, used as a control. The following characteristics were evaluated: color (lightness, redness and yellowness), weight (whole, nut and apple), apple length and diameter (upper and lower), oligomeric phenolic, total soluble solids (TSS), total titratable acidity (TTA), TSS/TTA ration and vitamin C. Detection of candidate QTLs were realized using the methods non-parametric mapping, interval mapping and multiple QTL mapping. The results evidence high phenotypic variability in the generation F1 for all characters analyzed, with potential for the selection of genotypes with the best characteristics for fresh fruit market. The QTL analyses showed 54 QTLs associated with quality of cashew apple. The characteristic redness presented the lowest number of QTL (two), while apple weight demonstrated the highest number (seven). These QTLs explained 3.15 to 21.33 % of the total phenotypic variance. The results strongly support the presence of true QTLs. These QTLs are in the process of validation to be used in the marker assisted selection in cashew breeding programs.
163

ProteomicQTL (pQTL):Kopplungsanalyse zur Identifizierung genetischer Modulatoren des Plasmaproteoms

von Delft, Annette 02 May 2013 (has links) (PDF)
Ziel der vorliegenden Arbeit war die Identifizierung genetischer Faktoren, die das Plasmaproteom regulieren. Die Untersuchungen wurden im Modellsystem einer F2-Kreuzung zweier Inzucht-Mausstämme (FVB.LDLR-/-, C57BL/6.LDLR-/-) durchgeführt, die sich in ihrer Atheroskleroseausprägung unterscheiden. Von jedem der 453 Tiere der F2-Generation wurden Plasmaproteomprofile mittels Massenspektrometrie (MALDI-TOF) generiert. Diese Spektren wurden in zwei unabhängigen Datenanalysen ausgewertet und eine Kopplungsanalyse (QTL-Analyse, quantitative trait loci) der Phänotypen mit jeweils 192 genetischen Markern in jedem der F2-Tiere durchgeführt. So wurden die Datensätze von Proteom und Genom miteinander kombiniert, um Genorte, die mit unterschiedlich regulierten Proteinen in Verbindung stehen, zu identifizieren. Dieser Ansatz ist bisher in der Literatur nicht beschrieben worden. In der vorliegenden Arbeit wird sowohl die Methodik der statistischen Auswertung als auch die weitere Analyse der generierten Daten beschrieben. Es wurden zahlreiche hochsignifikante Kopplungssignale gefunden, von denen zwei durch die Identifizierung von Proteinen verifiziert werden konnten. Es handelt sich hierbei um das Apo-A2 des HDL auf Chromosom 1 und Hämoglobin subunit alpha auf Chromosom 11. Eine Kolokalisation der gefundenen Proteine mit Loci der Atherosklerosedisposition konnte nicht identifiziert werden. Dieser Ansatz zeigt erstmals, dass eine hypothesenfreie Verbindung proteomischer und genomischer Daten möglich ist und zur Identifizierung genetisch regulierter Plasmaproteine beitragen kann.
164

Etude de la maturation ovocytaire chez les vaches : effet de l'haplotype pour QTL-FERT-F-BTA3 et effet du métabolisme lipidique / Oocyte maturation study in cows : effects of the haplotype for the QTL-F-FERT-BTA3 and effect of lipid metabolism

Brisard, Daphné 28 March 2014 (has links)
Chez la vache Prim’Holstein, un QTL de fertilité a été localisé sur le chromosome 3, et deux haplotypes ont été déterminés : « Fertil+ » et « Fertil- ». Les « Fertil- » ont un plus fort taux d’échec de gestation précoce. Le 1er objectif de cette thèse était de déterminer si un dysfonctionnement des complexes ovocyte-cumulus (COC) pouvait expliquer l’échec précoce de gestation chez les « Fertil- ». L’analyse révèle un retard de maturation, une dérégulation de gènes appartenant aux voies des prostaglandines et des MAPK, et à la famille des Tribbles dans les CC ou l’ovocyte des « Fertil- ». Trois gènes composent la famille des Tribbles chez le bovin: TRIB1, TRIB2 et TRIB3, leur fonction est indéterminée dans le COC. Le 2nd objectif était de caractériser le patron d’expression des Tribbles et leur(s) fonction(s) au sein du COC bovin. Les Tribbles joueraient un rôle dans le métabolisme lipidique et l’inflammation au niveau folliculaire. Le métabolisme lipidique au sein du COC bovin étant peu caractérisé, le 3ème objectif était d’appréhender les profils des gènes du métabolisme des acides gras (AG) dans les CC au cours de la maturation. Ainsi, les CC expriment les gènes lipotytiques et lipogéniques. Enfin, la β-oxydation des AG est une fonction primordiale pour la maturation ovocytaire. / In Prim’Holstein cow, a fertility QTL was localized on chromosome 3 and two haplotypes were determined: « Fertil+ » and « Fertil- ». « Fertil- » have a higher early pregnancy failure rate. The 1st objective of the thesis was to define if complex oocyte-cumulus COC dysfunction could explain the early pregnancy failure in « Fertil- ». Analysis highlighted a maturation delay, a dysregulation of genes involved in prostaglandin and MAPK pathway along with one member of the Tribbles family in « Fertil- » CC or oocyte. In bovine, the Tribbles family is composed of three genes: TRIB1, TRIB2 and TRIB3, their function is unknown within the COC. The 2nd objective was to characterize the Tribbles expression pattern and their function in the bovine COC. The tribbles might play a role in lipid metabolism and in inflammation at the follicular level. Lipid metabolism within bovine COC is poorly understood, thus the third objective was to apprehend fatty acid (FA) genes pattern in CC during maturation. Thus, CC express lipolytic and lipogenic genes. Lastly, FA β oxidation is found to be important for oocyte maturation.
165

Caracterização de germoplasma, herança e identificação de marcadores SNP associados à resistência a Podosphaera xanthii em meloeiro / Germplasm characterization, inheritance and identification of SNP markers associated with resistance to Podosphaera xanthii in melon

Nunes, Elaíne Welk Lopes Pereira 04 April 2014 (has links)
Made available in DSpace on 2016-08-12T19:18:32Z (GMT). No. of bitstreams: 1 ElaineWLPN_TESE.pdf: 787916 bytes, checksum: 2087efc39ac35d1b19fedd7e4362e6bf (MD5) Previous issue date: 2014-04-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Powdery mildew, caused by Podosphaera xanthii, is the most important foliar disease of cucurbits in the Northeast Brazil. Breeding for resistance is one of the best ways to control this pathogen. The objectives aims these work were to characterize morphologically and by microsatellites markers resistant accessions of melon, to study the inheritance and to identify SNP markers associated to resistance in the accessions AM55-1A and C-AC-15. Fifty-six melon plant accessions with different geographical origins were evaluated for resistance to P. xanthii using artificial inoculation procedure under greenhouse conditions. The resistant accessions C-AC-02, C-AC-09, C-AC-15, C-AC-34 and AM55-1A were characterized with morphological traits and microsatellites markers. The accessions C-AC-02, C-AC-09, C-AC-15, C-AC-34 exhibited characteristics of momordica botanical variety while the accession AM55-1A exhibited characteristics of acidulus botanical variety. The molecular characterization confirmed he results observed in morphological characterization. The inheritance of resistance in AM55-1A and C-AC-15 in crosses with susceptible cultivar Véndrantais was studied under greenhouses conditions. The segregations ratios for resistance/susceptibility observed in the different populations (F1, F2, BC1 and BC2) indicated a monogenic and dominant inheritance in AM55-1A and two independent genes with epispastic interaction double recessive control resistance in C-AC-15. The backcross population (BC1) derived from AM55-1A x Véndrantais and F2 population from C-AC-15 x Véndrantais were utilized to identify QTLs associated to resistance to P. xanthii using bulked segregation analysis with 243 SNP molecular markers. Two QTLs (Pm-AM55-1A_1 and Pm-A55-1A_2) were identified on ligation group V from AM55-1A x Véndrantais . One QTL (Pm-C-AC-15_5) on ligation group V and other (Pm-C-AC-15_9) on ligation group IX / O oídio causado por Podosphaera xanthii, é a doença foliar mais importante das cucurbitáceas no Nordeste do Brasil. O melhoramento genético para resistência é uma das melhores maneiras de controlar esse patógeno. Os objetivos deste trabalho foram caracterizar morfologicamente e por marcadores microssatélites acessos resistentes de melão, estudar a herança e identificar marcadores SNP associados à resistência nos acessos AM55-1A e C-AC-15. Cinqüenta e seis acessos de meloeiro com diferentes origens geográficas foram avaliados para a resistência a P. xanthii usando inoculação artificial em casa de vegetação. Os acessos resistentes C-AC-02, C-AC-09, C-AC-15, C-AC-34 e AM55-1A posteriormente foram caracterizados utilizando descritores morfológicos e marcadores microssatélites. Os acessos C-AC-02 , C-AC-09, C-AC-15, C-AC-34 exibiram características da variedade botanica momordica, enquanto o acesso AM55-1A exibiu características da variedade botânica acidulus. A caracterização molecular confirmou os resultados observados na caracterização morfológica. A herança da resistência em AM55-1A e C-AC-15 em cruzamentos com a cultivar suscetível Véndrantais foi estudada em condições de casa de vegetação. As razões de segregação resistência/suscetibilidade observadas nas diferentes populações (F1, F2, RC1 e RC2) indicou herança monogênica e dominante em AM55-1A e dois genes independentes com interação epistática duplo recessiva no controle genético em C-AC-15. A população de retrocruzamento (RC1) derivado do cruzamento AM55 -1A x Véndrantais e a população F2 do cruzamento C-AC-15 x Véndrantais foram utilizados para identificar QTLs associados à resistência a P. xanthii usando análise de bulk segregante com 243 marcadores SNP. Dois QTLs (Pm-AM55-A_1 e Pm-A55-1A_2) foram identificados no grupo de ligação V no cruzamento AM55-1A x Véndrantais . Foram identificados um QTL (Pm-C-AC-15_5) no grupo de ligação V e outro (Pm-C-AC-15_9) no grupo de ligação IX
166

Le test toxinique : une méthode de phénotypage pour l’étude de l’interaction Hevea brasiliensis x Corynespora cassiicola et l'identification des facteurs génétiques de sensibilité / The toxinic test : a phenotyping method for studying interaction Hevea brasiliensis x Corynespora cassiicola

Tran, Dinh Minh 15 November 2016 (has links)
Hevea brasiliensis est la seule source commerciale du caoutchouc naturel. La maladie CLF (Corynespora Leaf Fall) provoquée par le champignon Corynespora cassiicola est une pathologie foliaire de l’hévéa importante en Asie et en Afrique. Les épidémies sont liées au développement de nouvelles variétés clonales très sensibles. Une méthode conductimétrique de phénotypage de la réponse de l’hévéa aux exsudats de C. cassiicola (filtrats de culture ou toxine purifiée) a été développée et caractérisée. Ce test toxinique, sans contact direct avec le champignon lui-même, peut être mis en œuvre sans risque sur les plantations. Après application de gouttes d’exsudats sur des folioles détachées d’un génotype d’hévéa, deux mesures de conductivité C1 et C2 sont réalisées avant et après autoclavage, et le pourcentage de fuite d’électrolyte dû au traitement, %FE = 100*C1/C2, est calculé. L’influence de différents facteurs tels que le stade foliaire et la durée d’incubation, a été précisée. Une corrélation positive a été trouvée entre les réponses au test toxinique et à l’inoculation par des conidies du champignon. La pertinence de la correction de C1 par C2 a été analysée.Deux études du test toxinique ont été réalisées pour une série de clones d’hévéa, d’une part en France avec des plantes en pots cultivées en serre, et d’autre part en Côte d’Ivoire, dans les conditions normalement envisagées pour ce test, avec des folioles provenant de jardins à bois de greffe. La répétabilité entre ces deux études est imparfaite mais néanmoins satisfaisante. Le critère %FE est apparu plus sensible et plus précis que la mesure de la surface de nécrose induite (SN). Une variabilité importante de la sensibilité des clones et de l’agressivité des exsudats a été observée, avec l’existence d’interactions. L’analyse du déterminisme génétique de la réponse au test toxinique a été menée par détection de QTL sur deux populations de la famille biparentale d’hévéa PB260 x RRIM600, analysées sur deux sites en Côte d’Ivoire. Une carte génétique a été construite au préalable avec 308 marqueurs SSR. Le phénotypage des deux populations a révélé un déterminisme polygénique, sans effet monolocus majeur, avec, pour l’ensemble des exsudats fongiques étudiés, 13 QTL répartis sur 10 groupes de liaison et présentant des pourcentages d’explication R2 variant de 10 à 20 %. Sur les deux sites, deux QTL ont été identifiés conjointement pour le filtrat CCP et pour la toxine Cas1 purifiée à partir du filtrat CCP, démontrant l’importance de Cas1 pour la toxicité de ce filtrat. Des corrélations positives entre certains filtrats ont été observées, avec des profils de réponse similaires et des QTL communsLe test toxinique pourrait remplacer avantageusement la méthode d’inoculation conidienne. Cependant, la valeur prédictive du test pour la sensibilité des clones d’hévéa à la maladie CLF en plantation reste à caractériser. Une meilleure connaissance de l’épidémiologie du pathosystème H. brasiliensis x C. cassiicola contribuerait à l’objectif de sélection, et plus largement à la conception de méthodes de lutte ou d’évitement. / Hevea brasiliensis is the only commercial source of natural rubber. The CLF (Corynespora Leaf Fall) disease caused by the fungus Corynespora cassiicola is an important foliar pathology of the rubber tree in Asia and Africa. The disease progression is related with the development of new highly sensitive clonal varieties. A phenotyping method based on the measurement of electrolyte leakage in response to C. cassiicola exudates (culture filtrates or purified toxin) was developed and characterized. This test, without direct contact with the fungus itself, can be implemented without risk for plantations. After application of exudate samples on detached leaflets, conductivity is measured before (C1) and after (C2) autoclaving, and the percentage of electrolyte leakage %FE=100*C1/C2 is calculated. The influence of different factors such as leaf stage or the duration of incubation has been clarified. A positive correlation was found between the responses to the toxin test and to conidial inoculation. The pertinence of C1 correction by C2 was analyzed.Two toxin test studies have been carried out for a set of rubber clones, in France, with potted plants in greenhouse, and also in Ivory Coast, under the conditions normally considered for this test, with leaflets from budwood gardens. Repeatability between these two experiments was not perfect but nevertheless satisfying. The %FE character was found more sensitive and accurate than surface necrosis (SN) measurement. A significant variability in clone susceptibility and treatment virulence was observed, with clone x treatment interactions. The genetic determinism of sensitivity to C. cassiicola exudates was analyzed using the toxin test, by QTL detection on two populations of the biparental rubber family PB260 x RRIM600, in two field trials in Ivory Coast. A genetic map was previously built, using 308 SSR markers. Phenotyping of the two progeny populations revealed a polygenic determinism, without major monolocus effect. Over all the fungal exudates, 13 QTL distributed over 10 different linkage groups were identified, with percentages of explanation R2 varying from 10 to 20 %. On both sites, two QTL have been identified jointly for both the culture filtrate CCP and the toxin Cas1 purified from CCP. Positive correlations have been observed between some of the filtrates, with similar response profiles and common QTL.The toxin test could usefully replace the conidial inoculation method. However, the value of the test for predicting rubber clones susceptibility to the CLF disease in field conditions remains to be better characterized. Better understanding of the epidemiology of the H. brasiliensis x C. cassiicola pathosystem would contribute to the breeding objective, and more broadly to the design of control or avoidance methods.
167

Mapeamento de QTLs associados a conteúdo de proteína, óleo e componentes de produção em soja / QTL mapping associated to protein content, oil and production components in soybean

Rodrigues, Josiane Isabela da Silva 26 February 2008 (has links)
Made available in DSpace on 2015-03-26T13:42:07Z (GMT). No. of bitstreams: 1 texto completo.pdf: 334704 bytes, checksum: 88b0cef0d0e14e1c75e6e5e034dca776 (MD5) Previous issue date: 2008-02-26 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The improvement programs have been concerned, more and more, with the development of productive varieties and with high protein content and oil. The use of molecular markers in studies of genetic mapping has been taking the identification of QTLs involved with the genetic control of several characteristics of interest in soybean, above all, productivity and protein content and oil of the grain. In spite of the considerable number of QTLs mapped for such characters available in the literature, it still exist limited and inconsistent information about the confirmation of these QTLs. This work had as objectives the identification of QTLs associated to protein content (PTN) and oil (OIL) and production components in soybean (weight of seeds for plant - WS; weigh of a hundred seeds - WH, number of nodules for plant - NN, number of seeds for plant - NS). The study of QTL mapping was permormed from 206 F2 individuals obtained of the crossing among the soybean line CS3035PTA276-1-5-2 (high protein and low oil content) and the variety UFVS2012 (low protein and high oil content). F3 plants were phenotypic evaluated for 11 characteristics of the soybean in an experiment that consisted of three repetitions or blocks, so that each F3 family was sowed in three repetitions. The results of the variance analyses and of the estimates of the genetic parameters of the characteristics indicated the existence of genetic variability in the population for the eleven characteristics at the level of significance of 1%. Besides, the existence of contrasts among the averages of the genitors was evidenced for most of the characteristics. With base in these results, the genetic potential of the population was confirmed for the study of QTL mapping. Forty eight microsatellite markers had his segregation assessed in the 206 F2 individuals. Were obtained nine linkage groups, formed by the grouping of 25 markers. The analyses of association of simple mark and simple and composed interval mapping were used to detect and to map genomic areas associated to the characteristics in subject. The analyses of QTL were driven by linkage group separately and addressed to the characteristics of the grain and to the production components, main focus of the work. Were identified four QTLs associated to the protein content in the linkage groups A1, D1a, G and I that explained among 6,24% and 18,94% of the phenotypic variation of the characteristic. Three QTLs for content oil were detected in the groups A1, I and O what explained among 17,26% and 25,93% of the variation of the characteristic. For production of grains were identified two QTLs in the linkage groups A1 and D1a that explained 12,32% and 9,03% of the phenotypic variation, respectively. In the linkage group A1 were still detected QTLs associated to the number of nodules by plant and number of seeds for plant. These QTLs explained 9,43% and 7,19% of the variation to these phenotypes, respectively. The population used in this work demonstrated great potential for the QTL mapping. And the considerable number of significant associations detected between markers and characteristics presupposes the existence of others QTLs that can be characterized by the analysis of more markers in certain areas. / Os programas de melhoramento têm se preocupado, cada vez mais, com o desenvolvimento de variedades produtivas e com altos conteúdos de proteína e óleo. A utilização de marcadores moleculares em estudos de mapeamento genético tem levado a identificação de QTLs envolvidos com o controle genético de diversas características de interesse em soja, sobretudo, produtividade e conteúdo de proteína e óleo do grão. Apesar do número considerável de QTLs mapeados para tais caracteres disponíveis na literatura, existe ainda informação limitada e inconsistente sobre a confirmação desses QTLs. Este trabalho teve como objetivos a identificação de QTLs associados a conteúdo de proteína (PTN) e óleo (OLEO) e componentes de produção em soja (peso de sementes por planta - PRO ; peso de cem sementes - PCS, número de vagens por planta - NVP, número de sementes por planta - NSP). O estudo de mapeamento de QTL foi realizado a partir de 206 indivíduos F2 obtidos do cruzamento entre a linhagem de soja CS3035PTA276-1-5-2 (alto teor de proteína e baixo teor de óleo) e a variedade UFVS2012 (baixo teor de proteína e alto teor de óleo). Plantas F3 foram avaliadas fenotipicamente para 11 características da soja em um experimento que constou de três repetições ou blocos, de forma que cada família F3 foi semeada em três repetições. Os resultados das análises de variância e das estimativas dos parâmetros genéticos das características indicaram a existência de variabilidade genética na população para as onze características ao nível de significância de 1%. Além disso, foi evidenciada a existência de contrastes entre as médias dos genitores para a maioria das características Com base nesses resultados, foi confirmado o potencial genético da população para o estudo de mapeamento de QTL. Quarenta e oito marcadores microssatélites tiveram sua segregação avaliada nos 206 indivíduos F2. Foram obtidos nove grupos de ligação, formados pelo agrupamento de 25 marcadores. As análises de associação de marca simples e mapeamento por intervalo simples e composto foram utilizadas para detectar e mapear regiões genômicas associadas as características em questão. As análises de QTL foram conduzidas por grupo de ligação separadamente e direcionadas as características do grão e aos componentes de produção, foco principal do trabalho. Foram identificados quatro QTLs associados ao conteúdo de proteína nos grupos de ligação A1, D1a, G e I que explicaram entre 6,24% e 18,94% da variação fenotípica da característica. Três QTLs para conteúdo óleo foram detectados nos grupos A1, I e O que explicaram entre 17,26% e 25,93% da variação da característica. Para produção de grãos foram identificados dois QTLs nos grupos de ligação A1 e D1a que explicaram 12,32% e 9,03% da variação fenotípica, respectivamente. No grupo de ligação A1 foram ainda detectados QTLs associados ao número de vagens por planta e número de sementes por planta. Estes QTLs explicaram 9,43% e 7,19% da variação para estes fenótipos, respectivamente. A população utilizada neste trabalho demonstrou grande potencial para o mapeamento de QTL. E o número considerável de associações significativas detectadas entre marcadores e características pressupõe a existência de outros QTLs que poderão ser caracterizados pela análise de mais marcadores em determinadas regiões.
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Genética da resistência à murcha-de-ceratocystis (Ceratocystis fimbriata) em Eucalyptus spp / Genetics of ceratocystis wilt (Ceratocystis fimbriata) resistance in Eucalyptus spp

Rosado, Carla Cristina Gonçalves 17 February 2009 (has links)
Made available in DSpace on 2015-03-26T13:42:16Z (GMT). No. of bitstreams: 1 texto completo.pdf: 591447 bytes, checksum: bc5b0512ef38e95e126af3f20c57ce47 (MD5) Previous issue date: 2009-02-17 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The ceratocystis wilt (Ceratocystis fimbriata) is currently, one of the most important diseases in commercial eucalypt plantations in Brazil. The main symptoms are wilting, canker and wood darkening. The use of resistant Eucalyptus genotypes is the best control method. Despite the existence of resistant genotypes, the genetic basis of resistance is unknown. Therefore, the present study aimed to: 1) determine the resistance level of Eucalyptus grandis and E. urophylla genotypes and estimate the possibility to transfer the resistance between these two species through controlled interspecific crosses, 2) build a genetic map, detect and quantify the effects of QTL on ceratocystis wilt resistance using microsatellite markers in an interspecific full sibling family. On the first part of this work five parents of E. grandis and 16 E. urophylla, and 30 progenies E. grandis x E. urophylla (18 to 25 plants per progeny) were evaluated. For resistance screening, five replicates of each parent and each individual progeny, were inoculated under controlled conditions with the SBS-1 C. fimbriata isolate. From 21 parents assessed, twelve were resistant and nine susceptible, independently on the pecies. Estimates of individual narrow (50%) and broad (59%) sense heritability suggested a high degree of genetic control and low allelic dominance of the trait. Wide genetic variation among and within families was detected, a fact that contributes to high heritability and genetic gain. A selection of the 50 clones most resistant in the evaluated families, indicated that the average lesion length in the progeny population can be reduced by 74.4%. On the second part, five replicates of 127 individuals of progeny DGxUGL [(E. grandis x E. dunnii) x (E. urophylla x E. globulus)] were evaluated for ceratocystis wilt resistance. The inoculations were conducted under controlled conditions using the C. fimbriata isolate SBS-1. The resistance response in individuals of the progeny followed a continuously variable allowing to analyze the characteristic quantitatively. Among the 114 microsatellite markers analysed, 110 were mapped on 15 linkage groups (LG), whose lengths ranged from 12.3 to 191.5 cM genetic distance. The genetic map was satisfactory saturated, with total length of 1352.01 cM and an average interval of 12.29 cM. For the simple mark analysis, four markers found located in the GL 3, 5, 8, and 10, had significant effect on the binding resistance QTL (F test, P ≤ 0.05). The method of Fulk & Cardon confirmed the four QTLs found and allowed to identify another one in the LG 1, which heritability ranged from 9.6 to 34.2. / A murcha-de-ceratocystis (Ceratocystis fimbriata) é atualmente uma das principais enfermidades em plantios comerciais de eucalipto no Brasil. Os principais sintomas causados pela doença são murcha, cancro, escurecimento radial do lenho e morte da planta. O uso de genótipos de eucalipto resistentes é a melhor alternativa de controle. Embora existam genótipos resistentes, a base genética da resistência não é conhecida. Sendo assim, no presente trabalho objetivou-se: 1) determinar o nível de resistência de genótipos de Eucalyptus grandis e E. urophylla e estimar a possibilidade de transferência da resistência por meio de cruzamentos interespecíficos controlados entre essas duas espécies; 2) construir um mapa genético, detectar e quantificar os efeitos de QTLs para resistência à murcha-de-ceratocystis utilizando marcadores microssatélites em uma família de irmãos completos proveniente de um cruzamento interespecífico. Na primeira parte do trabalho, avaliaram-se cinco genitores de E. grandis e 16 de E. urophylla, além de 30 progênies E. grandis x E. urophylla (18 a 25 plantas por progênie). Para a avaliação da resistência foram inoculadas, em condições controladas, cinco réplicas de cada genitor e de cada um dos indivíduos da progênie, com o isolodado SBS-1 de C. fimbriata. Dos 21 genitores avaliados, 12 foram resistentes e nove suscetíveis, independentemente da espécie. As estimativas das herdabilidades individuais no sentido amplo e restrito equivaleram a 59% e 50%, respectivamente, sugerindo que a resistência genética à murcha-deceratocystis apresenta alto grau de controle genético e baixa dominância alélica. Com a seleção dos 50 clones mais resistentes nas famílias avaliadas pode-se obter redução de 74,4% na média da extensão de lesões em relação à população das progênies. Na segunda parte do trabalho, cinco réplicas de 127 indivíduos da progênie DGxUGL [(E. dunnii x E. grandis) x (E. urophylla x E. globulus)] foram avaliadas quanto à resistência à murcha-de-ceratocystis. As inoculações foram realizadas em condições controladas utilizando o isolado SBS-1 de C. fimbriata. A resposta da resistência nos indivíduos da progênie seguiu uma variação contínua possibilitando analisar a característica de forma quantitativa. A progênie foi genotipada com 114 marcadores microssatélites, deste total, 110 foram mapeados em 15 grupos de ligação (GL), cujos comprimentos variaram de 12,3 a 191,5 cM. O mapa genético apresentou saturação satisfatória, com comprimento total de 1352,01 cM e intervalo médio de 12,29 cM. Pela análise de marca simples verificou-se que quatro marcadores, localizados nos GL 3, 5, 8 e 10, apresentavam efeito significativo quanto à ligação a QTL de resistência (Teste F; P≤0,05). O método de Fulker & Cardon confirmou os quatro QTLs encontrados, além de identificar mais um no GL 1, cujas herdabilidades variaram de 9,6 a 34,2.
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Detecção de locos de características quantitativas com efeito da origem parental dos alelos nos cromossomos 1, 2 e 4 de suínos / Detection of quantitative trait loci with parent-of-origin effects on pig chromosome 1, 2 and 4

Silva Filho, Miguel Inácio da 23 February 2010 (has links)
Made available in DSpace on 2015-03-26T13:42:16Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1580756 bytes, checksum: 350f6dfe8f9943efab139b47104445dc (MD5) Previous issue date: 2010-02-23 / Data from an F2 swine population, consisting of 600 animals derived from crosses between Piau sires and Commercial dams were used in order to detect QTL with parent-of-origin effects. Phenotypic data on performance, carcass, internal organs, viscera, carcass cuts and meat quality traits were collected in the F2 animals. The population was genotyped for 16 microsatellite loci covering the chromosomes 1, 2 and 144. Based on the genotypes a specific linkage map was constructed for this population. Association analyses were performed using interval mapping by regression for QTL detection. A decision tree for identifying QTL with parent-of-origin effects based on tests against the Mendelian mode of expression was used. Twenty three QTL were detected using the Mendelian model of analysis, three on the chromosome one, five on chromosome two and 15 on chromosome four. It was also detected 12 QTL with parentof-origin effects. Six of these QTL were identified on chromosome one, where three were paternally expressed and three were maternally expressed. Three QTL were detected on chromosome two, where one was paternally expressed and the other two were maternally expressed. The remaining three QTL were identified on chromosome four, all of them were paternally expressed. None of the QTL with parent-of-origin effects was detected by the Mendelian model. The results generated in this study may contribute to a better understanding of the genetic mechanisms involved in the control of quantitative traits. / Com o objetivo de detectar QTL com efeito da origem parental dos alelos, foram utilizados dados de uma população F2 de suínos, composta de 600 animais, obtidos a partir do cruzamento de machos Piau e fêmeas comerciais. Nos animais F2, foram avaliadas características de desempenho, carcaça, órgãos e vísceras, cortes de carcaça e qualidade de carne. Para a genotipagem de todos os animais, foram utilizados 16 locos de microssatélites distribuídos nos cromossomos 1, 2 e 4. Com o resultado da genotipagem, foi construído o mapa de ligação específico dos marcadores para a população desenvolvida. As análises de associação foram baseadas no mapeamento por intervalo usando métodos de regressão. Para identificar QTL com efeito da origem parental dos alelos, foi utilizada uma árvore de decisão baseada em testes contra o modelo de expressão Mendeliana. Usando o método de análise para esse tipo de expressão, foram detectados 23 QTL mendelianos: três no cromossomo 1, cinco no cromossomo 2 e 15 no cromossomo 4. Foram detectados também 12 QTL com efeito da origem parental dos alelos: seis no cromossomo 1 (três de expressão paterna e três de expressão materna), outros três no cromossomo 2 (um de expressão paterna e os outros dois de expressão materna) e três no cromossomo 4 (todos de expressão paterna). Nenhum dos QTL com efeito da origem parental dos alelos foi identificado pelo modelo Mendeliano. Os resultados obtidos podem contribuir para o melhor entendimento dos mecanismos genéticos envolvidos no controle das características quantitativas.
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Mapeamento de QTL para características de interesse industrial da madeira de Eucalyptus em progênie de híbridos interespecíficos / Genetic mapping of QTL for characteristics of industrial interest of the Eucalyptus’s wood in an interspecific hybrid progeny

Macedo , Luciano Medina 26 February 2009 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-09-21T11:32:31Z No. of bitstreams: 2 Dissertação - Luciano Medina Macedo - 2009.pdf: 2515834 bytes, checksum: e30a9d4d1538ea85e265eedf8a8e2396 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-09-21T11:32:53Z (GMT) No. of bitstreams: 2 Dissertação - Luciano Medina Macedo - 2009.pdf: 2515834 bytes, checksum: e30a9d4d1538ea85e265eedf8a8e2396 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-09-21T11:32:53Z (GMT). No. of bitstreams: 2 Dissertação - Luciano Medina Macedo - 2009.pdf: 2515834 bytes, checksum: e30a9d4d1538ea85e265eedf8a8e2396 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2009-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this work a genetic map and QTL mapping were built for growth and wood quality characters in a interspecific hybrids progeny of Eucalyptus. Samples of genomic DNA were isolated from 200 individuals belonging to a interspecific hybrids progeny. A screening of 300 pairs microsatellite loci (SSR) primers was done and from those 76 loci were selected to compose 19 tetraplex combinations, based in presence of valid polimorfism for QTL mapping and in quality of allele’s amplification. Among the 76 loci appraised in multiplex system, 14 presented significant distortion of segregation in χ2 test using "Criterion of Bonferroni" with 5% of significance, and they were excluded of mapping analyses. Using LOD 3 and recombination fraction of 0.40, 12 linkage groups compatible with described in other mapping works in Eucalyptus were identified. An integrated genetic map was obtained with total length of 1240 cM and medium distance among marks of 22 cM, It provides a covering genomic of approximately 75% in relation to genome size of Eucalyptus gender. A part of density appraised by pilodyn apparatus, all others characters showed QTL association through variance analysis (single marks analysis). For growth characters, four loci were associated to seven QTL and 19% for genotypic variation of diameter, 18% for height and 10% for volume these QTL were capable to explain. Among wood quality characters evaluated by NIRS, three QTL were capable to explain 17% of genotypic variance for density, while for yield cellulose, four QTL together were capable to explain 7,5% of this variance. For the characters related with lignin properties also evaluated by NIRS, were identified three QTL capable to explain 9% of genotypic variation for lignin quantity, and two QTL were capable to explain 6% of genotypic variation for siringil/guaiacil relationship. Most of identified QTL for different characters appraised in this work coincided with linkage groups and as well the amount of variance of QTL detected by other authors, which carried out QTL mapping for these same characters. Although comparatively the SAM showed inferior efficiency in relation to fenotypic selection, it can be useful for optimization of futures field experiments into progenies which QTL mapping already was accomplished, where only best genotypes can be stablished in field instead to whole progeny. The application of SAM in forest breeding programs is possible to be used in early selection starting from second breeding generation, using QTL information of crosses mapped in these breeding programs. However, QTL used for SAM should be robust in progenies where they were mapped, like as QTL identified in linkage group 9 for character DAP in this dissertation, that beside consistence datas in progeny DG x GL2, were capable to explain the same amount of variability for QTL mapped by Kirst et al. (2007) (12%), which used different genetic markers and techniques for QTL mapping. These results prove that application of SAM is viable in breeding programs, and apart of peculiarities in each crossing, certain linkage groups are stable among different progenies for a same character. / Neste trabalho foi construído um mapa genético e realizado o mapeamento de QTL para caracteres de crescimento e qualidade da madeira em uma progênie de híbridos interespecíficos de Eucalyptus. Foram isoladas amostras de DNA genômico de 200 indivíduos pertencentes a uma progênie de híbridos interespecíficos. A partir de 300 pares de primers microssatélites (SSR), foram selecionados com base na presença de polimorfismo válido para o mapeamento de QTL e na qualidade de amplificação de seus alelos, 76 locos para compor 19 combinações tetraplex. Dentre os 76 locos avaliados em sistema multiplex, 14 apresentaram distorção de segregação significativa no teste χ2 perante o “Critério de Bonferroni” com nível de significância de 5% e foram excluídos das análises de mapeamento. Utilizando LOD 3 e fração de recombinação de 0,40, foram identificados 12 grupos de ligação compatíveis com os descritos em outros trabalhos de mapeamento em Eucalyptus. Foi obtido um mapa genético integrado com comprimento total de 1240 cM e distância média entre marcas de 22 cM, que proporciona uma cobertura genômica de aproximadamente 75% em relação ao tamanho do genoma deste gênero. Com exceção da densidade avaliada por pilodyn, todos os outros caracteres avaliados apresentaram associação a QTL por análise de variância (análise de marcas simples). Para os caracteres de crescimento, quatro locos estiveram associados a sete QTL, sendo que o montante da variação genotípica que estes QTL foram capazes de explicar foi de 19% para diâmetro, 18% para altura e 10% para volume. Dentre os caracteres de qualidade da madeira avaliados por NIRS, três QTL foram capazes de explicar 17% da variância genotípica para densidade, enquanto para o rendimento de celulose quatro QTL foram capazes de explicar juntos 7,5% desta variância. Para os caracteres relacionados com as propriedades da lignina também avaliados por NIRS, foram identificados três QTL capazes de explicar 9% da variação genotípica do caráter teor de lignina, e dois QTL capazes de explicar 6% da variação genotípica para a relação siringil/guaiacil. A maioria dos QTL identificados para os diferentes caracteres avaliados neste trabalho coincidiram com os grupos de ligação e o montante da variância representada com QTL identificados nos trabalhos de outros autores que realizaram mapeamento de QTL para os mesmos caracteres avaliados. Embora comparativamente a seleção assistida por marcadores moleculares tenha apresentado eficiência inferior em relação à seleção fenotípica, ela pode ser muito útil na otimização de futuros experimentos de campo de progênies para as quais já foi realizado o mapeamento de QTL, onde somente os genótipos com desempenho superior poderão ser avaliados em campo ao invés de toda a progênie. A aplicação de SAM em programas de melhoramento genético florestal é possível para a seleção precoce a partir da segunda geração de melhoramento, sempre que forem utilizadas informações de QTL mapeados nos cruzamentos realizados por estes programas de melhoramento. No entanto, estes QTL que serão utilizados para SAM, devem ser robustos nas progênies onde eles foram mapeados, tal como os QTL identificados nesta dissertação no grupo de ligação 9 para o caráter DAP, que além da consistência dos dados da progênie DG x GL2, foram capaz de explicar o mesmo montante da variabilidade com QTL mapeados para este caráter (12%) por Kirst et al. (2007), que utilizaram diferentes marcadores genéticos e técnicas de mapeamento de QTL. Estes dados comprovam que a aplicação da SAM é viável em programas de melhoramento, e que apesar das peculiaridades únicas de cada cruzamento, determinados grupos de ligação apresentam estabilidade de QTL entre diferente progênies para um mesmo caráter.

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