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Mapeamento de genes associados à resistência da soja a ferrugem asiática (Phakopsora pachyrhizi) / Mapping of genes associated to Asian soybean rust (Phakopsora pachyrhizi)Batista, Carlos Eduardo de Araujo 18 June 2008 (has links)
O custo ferrugem que engloba gastos com fungicidas, os custos operacionais das aplicações, perdas de produção, e redução na arrecadação de impostos representa um elevado valor para sojicultura mundial. Assim, a ferrugem asiática da soja apresenta-se como um dos grandes desafios para a pesquisa agrícola nos próximos anos, pois o controle químico da doença é alternativa obrigatória enquanto não se dispõe de cultivares resistentes. Porém a prática representa aumento considerável no custo de produção. No Brasil estima-se que este custo, para duas aplicações gire, em torno de US$ 40,00.ha-1, sem contar os gastos operacionais com máquinas e combustível, ou seja, gasto apenas o fungicida. Considerando o exposto, este trabalho tem como objetivo avaliar duas fontes de resistência à ferrugem asiática da soja (PI 200487 e PI 459025A), e verificar se os genes responsáveis pela reação ao patógeno já foram descritos na literatura, ou seja, identificar seus respectivos grupos de ligação. A estratégia de segregantes agrupados (Bulked segregant analysis) foi utilizada para mapear os genes de interesse. Os resultados obtidos permitiram chegar as seguintes conclusões: a) a técnica BSA foi eficiente para detectar locos relacionados com a resistência à ferrugem asiática da soja; b) a PI 459025 (Bing Nam) apresenta o gene de resistência Rpp4 localizado no grupo de ligação G e c) A PI 200487 (Kinoshita) apresenta um gene diferente daqueles descritos na literatura, sendo este localizado no grupo de ligação N. Este gene pode ser denominado de Rpp5. / The costs due to Asian soybean rust, which consists of fungicides, operational application costs and reduction in paid taxes, represent severe losses for worldwide soybean production. Thus, Asian soybean rust represents one of the most challenging problems for agricultural research in the future, since chemical control of the disease is the obligated alternative while resistant cultivars are unavailable. However, fungicide application significantly increases production costs. In Brazil, it is estimated that the costs of two applications are of approximately US$ 40,00.ha-1, aside the operational costs incurred due to machinery and fuel, that is, the figure represents solely fungicide costs. Taking into account the previous considerations, the present work aims to evaluate two sources of resistance to Asian soybean rust (PI 200487 and PI 459025A), and to verify if the genes involved in pathogen-responses have already been described in previous work, by identifying their respective linkage groups. Bulked segregant analysis was used to map the genes of interest. The results allowed the following conclusions: a) BSA was effective to detect loci associated to Asian soybean rust resistance; b) PI 459025A (Bing Nam) carries the resistance gene Rpp4 mapped to the linkage group G and c) PI 200487 (Kinoshita) has a novel resistance gene mapped to the linkage group N. The identified gene is denominated Rpp5.
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Mapas de ligação e identificação de Locos Controladores de Características Quantitativas (QTLs) associados à resistência a Crinipellis perniciosa em acessos de cacaueiro (Theobroma cacao) originários da Amazônia Brasileira / Linkage Maps and Identification of Quantitative Trait Loci (QTL) associated with resistance to Crinipellis perniciosa in cacao (Theobroma cacao) acessions from the Brazilian AmazonAlbuquerque, Paulo Sérgio Bevilaqua de 18 May 2006 (has links)
A vassoura-de-bruxa (Crinipellis perniciosa) é a doença mais importante da cacauicultura no Brasil. Sua principal forma de controle é o emprego de variedades resistentes, entretanto, devido à estreita base genética encontrada nos plantios comerciais de cacaueiro, esta resistência tem sido freqüentemente quebrada. Os objetivos deste trabalho foram: selecionar novas fontes de resistência a C. perniciosa entre acessos de cacaueiro originalmente coletados na Amazônia Brasileira (série CAB), identificar por mapeamento genético locos controladores de características quantitativas (QTLs) associados a esta resistência nos genótipos selecionados; e avaliar a relação genética dos clones CAB utilizados como genitores resistentes nos cruzamentos contrastantes com os acessos selecionados por agricultores do Sul da Bahia e as fontes tradicionais de resistência a C. perniciosa. Com base na proporção de infecção de vassoura-de-bruxa, foram avaliados os níveis de resistência a C. perniciosa de 44 famílias de cacaueiro em condições de casa de vegetação e campo. Nos ensaios de casa de vegetação, as médias das proporções de infecção foram comparadas através de contrastes pelo teste de Wald, e nos de campo por análise de medidas repetidas e contrastes. Dentre as famílias avaliadas em casa de vegetação e campo, as que apresentaram menores incidências de sintomas de vassoura-de-bruxa foram aquelas derivadas de CAB 0169, CAB 0208, CAB 0214, CAB 0270, CAB 0371, CAB 0388, CAB 0392 e CAB 0410. Foram desenvolvidos dois mapas de ligação conjuntos para as populações dos cruzamentos contrastantes entre os acessos selecionados como mais resistentes a C. perniciosa e o genitor suscetível ICS 39. Nas construções dos mapas de ligação foram utilizados 65 locos de microssatélites. Para a família derivada do cruzamento de ICS 39 x CAB 0208 foram formados 11 grupos de ligação com cobertura total de 541 cM e distância média entre marcas de 14 cM. O mapa de ligação ICS 39 x CAB 0214 apresentou cobertura total de 501 cM nos 10 grupos de ligação formados com distância média entre marcas de 11,4 cM. Dectataramse três QTLs associados à resistência a C. perniciosa, um no grupo de ligação VIII de ICS 39 x CAB 0208 e dois no mapa de ICS 39 x CAB 0214, sendo um no grupo de ligação IV e outro no grupo IX. A relação genética entre os dois clones CAB genitores das populações contrastantes e 81 genótipos de cacaueiro utilizados como fontes de resistência a C. perniciosa foram baseadas nas freqüências alélicas de 20 locos de microssatélites. As análises de dissimilaridade genética entre os acessos de cacaueiro originaram dois grupos. Os CAB 0208 e CAB 0214 não fizeram parte dos grupos formados. O grau de parentesco entre estes dois acessos foi muito alto, chegando próximo ao de irmãos-germano, não sendo aparentados com nenhum dos outros acessos. Os clones selecionados por agricultores derivam na sua maioria de Scavina 6, a fonte de resistência comumente empregada. / The witches broom (Crinipellis perniciosa) is the most important disease of cacao in Brazil. The main method of disease control is the use of resistant cultivars, however due to the narrow genetic basis found in commercial cacao growing areas, the resistance is frequently broken. The objectives of this work were: to select new sources of resistance to C. perniciosa among cacao accessions originally collected in the Brazilian Amazon (CAB series); to identify by genetic mapping, quantitative trait loci (QTLs) associated with resistance in selected genotypes; and to evaluate the genetic relationship between the selected accessions and clones selected by cacao growers from Southern Bahia with traditional resistance sources against C. perniciosa. Based on the proportion of witches broom infection, the levels of resistance to C. perniciosa were estimated in 44 cacao families under greenhouse and field conditions. Under greenhouse conditions, the average proportion of infection was compared based on Wald test, and under field conditions using an analysis of repeated measures and contrast. Among the families evaluated under greenhouse and field conditions, the ones with least incidence of witches broom symptoms derived from CAB 0169, CAB 0208, CAB 0214, CAB 0270, CAB 0371, CAB 0388, CAB 0392 and CAB 0410. Two linkage maps were developed for populations derived from crosses between contrasting accessions selected as the most resistant to C. perniciosa (CAB 0208 and CAB 0214) and a susceptible accession ICS 39. The linkage maps were developed using 65 microsatellite loci, applying the software JoinMap 3.0®. The identification and localization of QTLs associated with resistance to C. perniciosa were performed using MAPQTLTM 4.0. For the family derived from ICS 39 x CAB 0208, 11 linkage groups were formed, with total coverage of 541 cM and 14 cM average distance between markers. The linkage map from ICS 39 x CAB 0214 presented a total coverage of 501 cM in 10 linkage groups formed with an average distance between markers of 11.4 cM. Three QTLs associadted with resistance to C. perniciosa were detected, with one at linkage group VIII of ICS 39 x CAB 0208, and two for the ICS 39 x CAB 0214 family, with one located at linkage group IV and another at group IX. The genetic relationship between these two CAB accessions and 81 genotypes used as source of resistance to C. perniciosa were determined using genetic dissimilarity and co-ancestry based on allele frequencies of 20 microsatellite loci. The dissimilarity analyses among the accessions generated two distinct groups. CAB 0208 and CAB 0214 did not belong to any of the two groups. The co-ancestry between the two accesions were high, close to full-sib, but without any relationship with any of the other genotypes. The clones selected by growers derived mostly from Scavina 6, a commonly used source of resistance to C. perniciosa.
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Soutien à l'autodétermination, personnalité et conséquences émotionnelles chez les patients hospitalisés en service de soins de suite et réadaptation : apport de la théorie de l'autodétermination / Autonomy support, personnality, and emotionals outcomes in older people hospitalized in after-care and rehabilitation services : contribution of the Self-Determination theorySouesme, Guillaume 07 December 2018 (has links)
L’hospitalisation représente une étape de vie à laquelle doit faire face une grande majorité des personnes âgées. Cette expérience trop souvent accompagnée d’un déclin physique et psychologique marque pour beaucoup le début de la fin. Basé sur les fondements théoriques de la théorie de l’autodétermination (TAD), ce travail doctoral a deux objectifs. (1) Définir qualitativement le soutien à l’autodétermination dans les services de soins de suite et réadaptation (SSR). (2) Connaître l’impact des orientations de causalité́ des patients sur la perception de soutien ou de contrôle à l’autodétermination et les conséquences motivationnelles et émotionnelles associées. L’étude 1 a montré que les professionnels de santé mettaient en avant une image idéalisée de leur environnement de soins. Les patients (étude 2) ont indiqué de nombreuses contraintes qui atténuent l’effet de cette vision positive. L’étude 3 a démontré que les orientations de causalité du patient étaient une variable qui en interaction avec la perception de l’environnement, n’aboutissait pas aux mêmes conséquences motivationnelles et émotionnelles. De par le rôle déterminant octroyé par la TAD à la motivation, les professionnels de santé se doivent d’être capables de nourrir, entretenir et soutenir la motivation des patients. Une réflexion sur les recommandations pratiques et des axes de recherches futurs seront proposés. / Hospitalization is a life stage that faces a large majority of older people. This experience is often accompanied by both physical and psychological declines and means, for most of older people the beginning of the end. Based on the self-determination theory (SDT), this doctoral dissertation has two objectives. (1) To qualitatively define an autonomy supportive environment in after-care and rehabilitation services (ACRS). (2) To know the impact of causality orientations on patients' perceptions of an autonomy supportive or controlled environment and the associated motivational and emotional consequences. Study 1 showed that healthcare professionals conveyed an idealized image of their work environment and the care they provide. Patients (study 2) indicated many constraints that mitigated the effect of this positive view of an autonomy supportive environment and reduced their ability to experience it. Study 3 demonstrated that patient's causality orientations were a variable which interacted with the perception of ACRS environment, did not induce the same motivational and emotional consequences. Thus, these studies contribute to the self-determination theory in the health setting by showing the determining role of patients’ motivation. It is therefore necessary for healthcare professionals to be able to feed, maintain and support patients’ motivation. In the light of the contribution of the self-determination theory, a reflection about practical recommendations and future lines of research will be proposed.
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Utilisation de l'espèce sauvage diploide Gossypium australe F. Muell. pour l'amélioration de l'espèce cultivée tétraploïde G. hirsutum L. par la méthode des lignées monosomiques d'additionSarr, Djibril 12 September 2008 (has links)
Summary : The wild diploïd species Gossypium australe carry interesting agronomic characters such as resistance to wilt fusarium and "delay of the gossypol glands morphogenesis in the seed " that makes it an important source of variability for the genetic improvement of the main cultivated cotton species G. hirsutum. One of the approach to introgress these characters is to isolate and exploit monosomic alien addition lines (MAAL). In order to isolate new MAAL of G. australe in G. hirsutum, the [2(G.hirsutum x G.australe)x G.hirsutum] pentaploid was backcrossed as male parent to G. hirsutum. Among the 253 BC1 derivatives obtained, 106 plants (42%) presented morphological alterations attributed to presence of G. australe chromatin. To define an SSR linkage group for each of the 13 G. australe chromosomes, 42 plants representative of the phenotypic variability observed in the BC1 generation and seven alien addition lines already isolated in our laboratory were analyzed using SSR markers developed from the G. hirsutum species. Out of the 150 SSR markers used, 100 % amplified G. australe DNA and 84 (56 %) generated 89 polymorphic loci. All these loci but two have been assigned, by means of an cluster algorithm, to 13 linkage groups assumed to match up to the 13 chromosomes of the diploid species. On this basis, about 60% of the analyzed plants were multisomic addition lines, 20%, MAAL while 20 % carrying no markers were supposed to be euploid. The newly isolated MAAL appeared to be the same as those already available.
Five disomic alien addition plants carrying at least one additional chromosome different from the chromosomes of G. australe previously isolated in a monosomic addition configuration were selfed and the BC1S1 progenies obtained have been analyzed with SSR markers and GISH. Five new MAAL of G. australe in G. hirsutum have thus been isolated. In order to monitor the potentialities of using MAAL for the transfer of genetic material from the additional chromosome to the genetic background, the transmission frequency and integrity of the supernumerary chromosome have been analyzed with SSR markers in the self-progeny of five MAAL. Three of them revealed a transmission frequency significantly lower than the 3:1 expected ratio, one MAAL presented an exclusive preferential transmission of the additional chromosome. In these four MAAL the alien chromosome was transmitted almost unaltered. With the fifth MAAL the alien chromosome was normally transmitted but was altered in half of the plants containing G. australe chromatin. One of the investigated MAAL characterized by its brown fiber produced few plants carrying also white fibers. It has been shown that this mosaicism was due to the loss of the alien supernumerary chromosome. The complete loss of this chromosome seems to be linked to its fragmentation.
Résumé : L'espèce diploïde sauvage Gossypium australe possède des caractères agronomiques d'intérêt tels que la résistance au fusarium et le "retard à la morphogenèse des glandes à gossypol" qui en font une importante source de variabilité pour l'amélioration génétique de la principale espèce de cotonnier cultivé G. hirsutum. Une des approches pour l'introgression de ces caractères est la production et l'exploitation de lignées monosomiques d'addition (LMA). Pour isoler les LMA de G. australe sur G. hirsutum, le pentaploïde [2(G.hirsutum x G.australe)x G.hirsutum] a été rétrocroisé comme parent mâle avec l'espèce tétraploïde. Sur les 253 graines obtenues, 106 (42%) ont donné des plantes présentant une morphologie nettement distincte de celle de G. hirsutum. Cette différence a été attribuée à la présence de chromosomes de G. australe.
Afin de définir des groupes de liaison pour chacun des chromosomes de G. australe, 42 plantes représentatives de la variabilité phénotypique observée ainsi que 7 lignées d'addition déjà isolées ont été sélectionnées et analysées avec des marqueurs SSR développés sur l'espèce tétraploïde. Tous les 150 marqueurs utilisés ont amplifié l'ADN de G. australe et 84 (56%) ont généré 89 loci polymorphes. Tous ces loci, sauf deux, ont pu être assignés, par classification numérique, à 13 groupes de liaison supposés correspondre aux 13 chromosomes de l'espèce diploïde. Sur cette base, 60% des plantes analysées sont des plurisomiques d'addition; 20%, des LMA tandis que 20 % ne portant aucun marqueur ont été supposées euploïdes. Les nouvelles LMA isolées s'étant révélées être identiques à celles déjà isolées, 5 plantes disomiques d'addition portant au moins un chromosome non-encore isolé à l'état monosomique d'addition ont été autofécondées et leur descendance analysée avec des marqueurs SSR et par la GISH. Cinq nouvelles LMA ont pu ainsi être isolées. Afin d'étudier les potentialités d'utilisation de la méthode des LMA pour le transfert de matériel génétique de l'espèce sauvage vers l'espèce cultivée, la fréquence de transmission et l'intégrité du chromosome surnuméraire, a été analysée avec des marqueurs SSR dans une génération autofécondée de cinq LMA. Trois lignées ont donné un taux de transmission inférieur au ratio attendu de 3:1, chez la quatrième lignée le chromosome surnuméraire a été transmis à toute la descendance. Pour ces quatre lignées le chromosome additionnel a été transmis presque inaltéré. Avec la cinquième lignée, le chromosome additionnel a été transmis suivant le taux attendu mais a été altéré dans la moitié des plantes contenant de la chromatine de G. australe. Une des lignées analysées caractérisée par la couleur brune de ses fibres a produit quelques plantes portant également des fibres blanches. Il a été montré que ce mosaïcisme de la couleur des fibres était dû à la perte du chromosome additionnel. Cette perte semble être liée à une fragmentation du chromosome.
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Molecular Characterization Of Strawberry By Applying Dna Fingerprinting Technique Using Simple Sequence Repeats (ssrs) MarkersDernaika, Maher 01 December 2009 (has links) (PDF)
In this study, strawberry fruit was taken as the studied model. An attempt was carried on trying to identify a unique DNA fingerprint in each of the selected different strawberry cultivars of Fragaria x ananassa Duch species available in Turkey. The basis of the study was to examine the fruit characteristics at the molecular level rather than at the morphological level. It is of great importance to differentiate and trace the origin of any variety by examining its DNA by using a very sophisticated molecular technique. In this case, DNA fingerprinting technique depending on the Simple Sequence Repeats (SSRs) markers which are also called Microsatellite markers were used. DNA fingerprinting technique reveals the specific DNA profile which is unique as a fingerprint for a fruit specimen and this DNA profile is the same and constant throughout different parts of the fruit as well as its developmental stages. In this thesis work, nine primers flanking the SSR markers already available in the online databases were designed hoping to detect SSRs that could differentiate among the five selected cultivars of strawberry.
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Genetic Basis of Tocopherol Accumulation in Soybean (Glycine Max [L.] Merr.) SeedsShaw, Eric 23 November 2012 (has links)
This thesis is an investigation of the genetic basis of tocopherol accumulation in soybean (Glycine max [L.] Merrill) seeds. Soybean is the world’s most widely grown protein and oilseed crop and the principle source of vitamin E (tocopherols) as a supplement. Tocopherols (α-, β-, γ- and δ-isomers) are powerful antioxidants that contain human health benefits, including a decrease in the risk of lung cancer, heart disease and osteoporosis. The purpose of this research was to identify genetic and biochemical components affecting tocopherol accumulation in soybean seeds. The objectives were to: 1) investigate location and year effects on soybean seed tocopherol levels in the field; 2) determine environmental factors affecting soybean seed tocopherol levels under controlled conditions; 3) identify simple sequence repeat (SSR) markers that tag quantitative trail loci (QTL) for individual and total tocopherols; and 4) evaluate the potential role of VTE1, VTE3 and VTE4 genes in tocopherol accumulation using the candidate gene approach. Seventy nine recombinant inbred lines (RILs) derived from the cross between OAC Bayfield and OAC Shire were grown in the field at Elora, Woodstock and St. Pauls, ON, in 2009 and 2010. The tocopherol components were quantified using high performance liquid chromatography (HPLC). The results showed a significant (p < 0.001) genotype, environment and genotype x environment effect for each tocopherol component. It was discovered that a 2 x phosphate fertilizer (K2SO4 at 1.0M/150mL) and 30 ˚C temperature treatment increased each tocopherol component, whereas drought had no effects. Single marker analysis identified 42 QTL and interval mapping identified 26 QTL across 17 chromosomes. Significant two-locus epistatic interactions were found with a total of 122 and 152 in the 2009 and 2010 field seasons, respectively. The multiple locus models explained 18.4% to 72.2% with an average of 45.7% of the total phenotypic variation. The candidate gene approach using nucleotide sequences from the coding regions identified two single nucleotide polymorphisms (SNPs) in VTE1, five SNPs in VTE4 and none in VTE3. The SNPs were predicted to cause functional protein changes and the genes co-localized with some of the identified QTL. The results of this study provide a better understanding of the environmental factors and genetic mechanisms that influence the accumulation of tocopherols in soybean seeds. / Grain Farmers of Ontario, Vitamin Research Award
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Scaffolded Self-Selected ReadingJanuary 2011 (has links)
abstract: The federal No Child Left Behind Act has set the goal that all students in every state shall be proficient in reading by 2014. Arizona teachers face the challenge of having 100 percent of their students meeting or exceeding grade level reading standards assessed by Arizona's Instrument to Measure Standards (AIMS). One of my goals as a reading teacher is to widen the range of options my students will have. My goal every year is to have my students read at or above grade level. I also am committed to inspiring students to become motivated to love literacy because voluntary lifelong reading is important in peoples' lives. The purpose of this study was to investigate conducting brief, interactive, weekly reading conferences during daily Scaffolded Self-Selected Reading (ScS-SR) sessions while incorporating Transactional Strategy Instruction with a pair-share with a partner, and to see if it would improve my students' reading motivation and comprehension. Data were collected via the Motivation to Read Profile Survey and Interview, informal observations, Dynamic Indicators of Basic Early Literacy Skills Oral Reading Fluency Test (DIBELS: ORF), and Oral Reading Records used by my school district. Findings concluded that students tended to become more willing readers, with several of them explicitly attributing their newfound willingness to read to my efforts. Most students became somewhat more aware of their reading experiences, explaining how different types of books in ScS-SR affected them. All students' reading comprehension performance improved, with measureable increases in students' instructional reading levels, retellings, and meaningful miscues that students attributed to leveled books, strategy instruction, and retellings. / Dissertation/Thesis / Ed.D. Leadership and Innovation 2011
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Building other people's armies : military capacity building and civil-military relations during international interventionsNeads, Alexander Stephen January 2016 (has links)
Following state-building campaigns in Iraq and Afghanistan, the UK has increasingly eschewed large-scale intervention in favour of local proxy forces. Whilst this strategy might appeal to the war-weary and cash strapped interventionist, frequent use of military capacity building as a tool of foreign policy inevitably raises questions about the accountability of those local forces being trained. This thesis examines the exportation of Western concepts of civil-military relations into the Republic of Sierra Leone Armed Forces (RSLAF), carried out by the British-led International Military Advisory and Training Team (IMATT) during intervention and post-conflict stabilisation in Sierra Leone. It argues that external interventionists can reshape local military culture, to promote both democratic civil-military norms and professional military effectiveness, but only through extensive institutional change. In Sierra Leone, IMATT attempted to change the organisational culture of the RSLAF by reforming its institutional mechanisms for socialisation, training, education and promotion. By inculcating a new normative ethos in a cohort of junior RSLAF officers, IMATT sought to promulgate cultural change throughout the military via a structured process of intra-service competition and generational replacement. This novel blend of internal and external processes of military change challenges existing scholarship on military innovation and adaptation, advancing our understanding of the relationship between military culture, military change, and external intervention. However, this process of institutional redevelopment and cultural change in the RSLAF proved to be both heavily contested and deeply political, ultimately leading to partial results. Consequently, IMATT’s experience of RSLAF reform holds important implications for the study of civil-military relations and security sector reform, and with it, the conduct of contemporary military capacity building and liberal intervention.
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Análise comparativa da variação genética entre os estoques cultivado e natural de Prochilodus argenteus : implicações para o repovoamento de riosCampos, Wagner Narciso de 24 July 2009 (has links)
Made available in DSpace on 2016-06-02T20:21:21Z (GMT). No. of bitstreams: 1
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Previous issue date: 2009-07-24 / Financiadora de Estudos e Projetos / Introduction of hatchery fish in river has been the major using strategy for river fishery rehabilitation, working to attenuate river damage in short time. But there are effective risks
about their efficiency and results, concerning the pool gene preservation and illness proliferation, beyond others ecologies and economics aspects. At São Francisco river, during two decades it was used this kind of procedure with some species of fish, but there are no quantitative data about their efficiency. Prochilodus argenteus, popular known as Curimatápacu, is pointed as the most important economic specie at São Francisco basin, responsible for 50% of all fishery production. Therefore, this project goals to trace the genetic profile of a Prochilodus argenteus hatchery population, looking for identify stock genetic variability
through 13 SSR loci previous described, and to compare theses data with others described in literature from wild stocks. Tests made with Microchecker, Genepop, and Fsat softwares detected low homozygosis; reduced allelic variability when compared with wild population; increase in heterozygosis when compared with expected; and negative inbreed coefficient, these data got a trace for bottleneck phenomena in a cultured population, and Bottleneck software tests confirm this hypothesis. When the same test was ruled with wild population data results very far from those found in hatchery populations, give a high reliability. To conclude, at cultured and/or management programs are necessary the knowledge of genetic profile population (hatchery or wild) to prevent damaging introgression in wild population and consequently extinction. These data can be used to made fishery river rehabilitation program more efficient, and so, adding with information to fish procreation, industrial fishery
and biologic fish conservation studies. / O repovoamento de rios é uma das estratégias que vem sendo frequentemente usada para a reabilitação pesqueira, atuando como uma medida mitigadora de curto prazo, embora envolva
riscos relativos à eficiência do programa quanto aos seus resultados, à preservação do pool genético e à possibilidade de introdução de doenças, além de outros aspectos ecológicos e econômicos. No rio São Francisco, esta prática vem sendo realizada há mais de duas décadas com algumas espécies de peixes. No entanto, não existem relatos quantitativos de sua eficiência. Prochilodus argenteus, conhecido popularmente como curimatã-pacu, constitui
uma espécie de relevante valor econômico para a bacia do São Francisco, representando cerca de 50% de toda produção de pescado. O presente trabalho teve como objetivo traçar o perfil genético de uma população de cultivo de Prochilodus argenteus, visando identificar a variabilidade genética deste estoque. Foram utilizados 13 loci de microssatélites previamente descritos na literatura e seus dados foram comparados com os de população selvagem de
trabalhos anteriores. Testes feitos com os programas Microchecker, Genepop e Fstat detectaram baixa homozigose, redução da variabilidade alélica quando comparada a estoques
naturais, um número aumentado de heterozigotos quando comparado com o esperado e coeficiente de endogamia negativo, tais dados apontam para um possível efeito gargalo
(bottleneck) recente na população cultivada. Testes feitos com o programa Bottleneck confirmaram essa hipótese. Resultado de tais teste se tornaram muito expressivos, quando o mesmo teste foi feito com dados de uma população selvagem para parâmetros de comparação. Os dados obtidos no presente trabalho demonstram que programas de manejo e cultivo do Prochilodus argenteus necessitam de um conhecimento do perfil genético da população (de cultivo ou selvagem), para que não haja introgressão deletéria na população selvagem com seu posterior declínio. Discussões sobre recuperação de ambientes aquáticos mostram que
ações integradas são necessárias para que de fato se tenha uma efetiva recuperação desses ambientes. Dados genéticos poderão subsidiar e viabilizar programas de peixamentos mais
eficientes e, assim, contribuir com estudos relacionados ao manejo de pesca, piscicultura e conservação biológica deste peixe.
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Mapas de ligação e identificação de Locos Controladores de Características Quantitativas (QTLs) associados à resistência a Crinipellis perniciosa em acessos de cacaueiro (Theobroma cacao) originários da Amazônia Brasileira / Linkage Maps and Identification of Quantitative Trait Loci (QTL) associated with resistance to Crinipellis perniciosa in cacao (Theobroma cacao) acessions from the Brazilian AmazonPaulo Sérgio Bevilaqua de Albuquerque 18 May 2006 (has links)
A vassoura-de-bruxa (Crinipellis perniciosa) é a doença mais importante da cacauicultura no Brasil. Sua principal forma de controle é o emprego de variedades resistentes, entretanto, devido à estreita base genética encontrada nos plantios comerciais de cacaueiro, esta resistência tem sido freqüentemente quebrada. Os objetivos deste trabalho foram: selecionar novas fontes de resistência a C. perniciosa entre acessos de cacaueiro originalmente coletados na Amazônia Brasileira (série CAB), identificar por mapeamento genético locos controladores de características quantitativas (QTLs) associados a esta resistência nos genótipos selecionados; e avaliar a relação genética dos clones CAB utilizados como genitores resistentes nos cruzamentos contrastantes com os acessos selecionados por agricultores do Sul da Bahia e as fontes tradicionais de resistência a C. perniciosa. Com base na proporção de infecção de vassoura-de-bruxa, foram avaliados os níveis de resistência a C. perniciosa de 44 famílias de cacaueiro em condições de casa de vegetação e campo. Nos ensaios de casa de vegetação, as médias das proporções de infecção foram comparadas através de contrastes pelo teste de Wald, e nos de campo por análise de medidas repetidas e contrastes. Dentre as famílias avaliadas em casa de vegetação e campo, as que apresentaram menores incidências de sintomas de vassoura-de-bruxa foram aquelas derivadas de CAB 0169, CAB 0208, CAB 0214, CAB 0270, CAB 0371, CAB 0388, CAB 0392 e CAB 0410. Foram desenvolvidos dois mapas de ligação conjuntos para as populações dos cruzamentos contrastantes entre os acessos selecionados como mais resistentes a C. perniciosa e o genitor suscetível ICS 39. Nas construções dos mapas de ligação foram utilizados 65 locos de microssatélites. Para a família derivada do cruzamento de ICS 39 x CAB 0208 foram formados 11 grupos de ligação com cobertura total de 541 cM e distância média entre marcas de 14 cM. O mapa de ligação ICS 39 x CAB 0214 apresentou cobertura total de 501 cM nos 10 grupos de ligação formados com distância média entre marcas de 11,4 cM. Dectataramse três QTLs associados à resistência a C. perniciosa, um no grupo de ligação VIII de ICS 39 x CAB 0208 e dois no mapa de ICS 39 x CAB 0214, sendo um no grupo de ligação IV e outro no grupo IX. A relação genética entre os dois clones CAB genitores das populações contrastantes e 81 genótipos de cacaueiro utilizados como fontes de resistência a C. perniciosa foram baseadas nas freqüências alélicas de 20 locos de microssatélites. As análises de dissimilaridade genética entre os acessos de cacaueiro originaram dois grupos. Os CAB 0208 e CAB 0214 não fizeram parte dos grupos formados. O grau de parentesco entre estes dois acessos foi muito alto, chegando próximo ao de irmãos-germano, não sendo aparentados com nenhum dos outros acessos. Os clones selecionados por agricultores derivam na sua maioria de Scavina 6, a fonte de resistência comumente empregada. / The witches broom (Crinipellis perniciosa) is the most important disease of cacao in Brazil. The main method of disease control is the use of resistant cultivars, however due to the narrow genetic basis found in commercial cacao growing areas, the resistance is frequently broken. The objectives of this work were: to select new sources of resistance to C. perniciosa among cacao accessions originally collected in the Brazilian Amazon (CAB series); to identify by genetic mapping, quantitative trait loci (QTLs) associated with resistance in selected genotypes; and to evaluate the genetic relationship between the selected accessions and clones selected by cacao growers from Southern Bahia with traditional resistance sources against C. perniciosa. Based on the proportion of witches broom infection, the levels of resistance to C. perniciosa were estimated in 44 cacao families under greenhouse and field conditions. Under greenhouse conditions, the average proportion of infection was compared based on Wald test, and under field conditions using an analysis of repeated measures and contrast. Among the families evaluated under greenhouse and field conditions, the ones with least incidence of witches broom symptoms derived from CAB 0169, CAB 0208, CAB 0214, CAB 0270, CAB 0371, CAB 0388, CAB 0392 and CAB 0410. Two linkage maps were developed for populations derived from crosses between contrasting accessions selected as the most resistant to C. perniciosa (CAB 0208 and CAB 0214) and a susceptible accession ICS 39. The linkage maps were developed using 65 microsatellite loci, applying the software JoinMap 3.0®. The identification and localization of QTLs associated with resistance to C. perniciosa were performed using MAPQTLTM 4.0. For the family derived from ICS 39 x CAB 0208, 11 linkage groups were formed, with total coverage of 541 cM and 14 cM average distance between markers. The linkage map from ICS 39 x CAB 0214 presented a total coverage of 501 cM in 10 linkage groups formed with an average distance between markers of 11.4 cM. Three QTLs associadted with resistance to C. perniciosa were detected, with one at linkage group VIII of ICS 39 x CAB 0208, and two for the ICS 39 x CAB 0214 family, with one located at linkage group IV and another at group IX. The genetic relationship between these two CAB accessions and 81 genotypes used as source of resistance to C. perniciosa were determined using genetic dissimilarity and co-ancestry based on allele frequencies of 20 microsatellite loci. The dissimilarity analyses among the accessions generated two distinct groups. CAB 0208 and CAB 0214 did not belong to any of the two groups. The co-ancestry between the two accesions were high, close to full-sib, but without any relationship with any of the other genotypes. The clones selected by growers derived mostly from Scavina 6, a commonly used source of resistance to C. perniciosa.
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