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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.
191

Implications of Local Puumala Hantavirus Genetics and Epidemiology for Diagnostics and Vaccine Development

Johansson, Patrik January 2005 (has links)
Puumala viruses, a member of the Hantavirus genus in the Bunyaviridae family, are enveloped by a lipid bilayer and possesses a tripartite single stranded RNA genome with negative polarity. The hantaviruses encode four proteins: a nucleocapsid protein (N), two membrane spanning glycoproteins (GN and GC) and a RNA dependent RNA polymerase (RdRp). Hantaviruses cause two forms of diseases, hemorrhagic fever with renal syndrome (HFRS) in Europe and Asia, and hantavirus pulmonary syndrome (HPS) in the Americas. The hantaviruses are mainly rodent borne, and humans are mostly infected by inhalation of aerosolized rodent secrete. Human Puumala virus infection results in nephropathia epidemica (NE), a mild haemorrhagic disease. It is of importance to have a good understanding of the epidemiology and genetics of these viruses for the development of new diagnostic methods and for future vaccine development. In this thesis we determined the complete viral genome sequence and characterized the structural proteins based on studies of expression and glycosylation patterns, for a unique human virus isolate; performed a genomic analysis of local Puumala viruses and their individual rodent host, Clethrionomys glareolus, from six different locations was performed. It was seen that the virus genetic variation between different locations could be stable over relatively large distances while there could be large variation over a short distance. For the bank voles no such variation could be seen; developed and evaluated Genetic vaccines, based on PCR-generated linear DNA. We showed that it was important to protect these fragments against nuclease degradation at that attachment of a nuclear localization signal peptide further improved the immune response. We also designed, fabricated and evaluated a 2000 probe cDNA-microarray for identification and differentiation of hantaviruses. The chips was based on 12 different strains of six hantaviruses and could differentiate between both different hantaviruses and strains within one hantavirus serotype.
192

Classes Alléliques d’Haplotypes et Sélection Positive dans le Génome Humain

Hussin, Julie 12 1900 (has links)
L'identification de régions génomiques cibles de la sélection naturelle positive permet de mieux comprendre notre passé évolutif et de trouver des variants génétiques fonctionnels importants. Puisque la fréquence des allèles sélectionnés augmente dans la population, la sélection laisse des traces sur les séquences d'ADN et ces empreintes sont détectées lorsque la variabilité génétique d'une région est différente de celle attendue sous neutralité sélective. On propose une nouvelle approche pour analyser les données de polymorphismes : le calcul des classes alléliques d’haplotypes (HAC), permettant d'évaluer la diversité globale des haplotypes en étudiant leur composition allélique. L'idée de l'approche est de déterminer si un site est sous sélection positive récente en comparant les distributions des HAC obtenues pour les deux allèles de ce site. Grâce à l'utilisation de données simulées, nous avons étudié ces distributions sous neutralité et sous sélection en testant l'effet de différents paramètres populationnels. Pour tester notre approche empiriquement, nous avons analysé la variation génétique au niveau du gène de lactase dans les trois populations inclues dans le projet HapMap. / Natural selection eliminates detrimental and favors advantageous phenotypes. This process leaves characteristic signatures in the underlying genomic segments that can be recognized through deviations in the allelic or in haplotypic frequency spectra. We introduce a new way of looking at the genomic single nucleotide polymorphisms : the haplotype allelic classes (HAC). The model combine segregating sites and haplotypic informations in order to reveal useful characteristics of the data, providing an identifiable signature of recent positive selection that can be detected by comparison with the background distribution. We compare the HAC distribution's partition between the haplotypes carrying the selected allele and the remaining ones. Coalescence simulations are used to study the distributions under standard population models assuming neutrality, demographic scenarios and selection models. To test, in practice, the performance of HAC and the derived statistic in capturing deviation from neutrality due to selection, we analyzed the genetic variation in the locus of lactase persistence in the three HapMap populations.
193

Bacillus thuringiensis: diversidade gênica, estrutura genética de populações e eficiência no controle de Plutella xylostella (L., 1758) (Lepidoptera: Plutellidae)

Thuler, Ana Maria Guidelli [UNESP] 21 September 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-09-21Bitstream added on 2014-06-13T20:24:20Z : No. of bitstreams: 1 thuler_amg_dr_jabo.pdf: 1407432 bytes, checksum: d7e6ed286b2d4a2ad8e9b2120b24b7ca (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O trabalho foi desenvolvido no Laboratório de Genética de Bactérias e Biotecnologia Aplicada (LGBBA) da FCAV-UNESP. Foram caracterizados geneticamente, por PCR, isolados de Bacillus thuringiensis, provenientes de três coleções brasileiras, quanto aos tipos de genes cry1, avaliando-se o efeito dos mesmos sobre uma população de Plutella xylostella caracterizando-se também os isolados de B. thuringiensis quanto à presença de enterotoxinas HBL, NHE e o regulador pleitrópico PLC, por verificação biomolecular, avaliando a variabilidade, bem como a estruturação genética de populações de B. thuringiensis, por PCR-RFLP. Verificou-se que existe uma distribuição homogênea das subclasses cry1 dentro do banco de isolados de B. thuringiensis, com maior porcentagem de isolados portadores dos genes cry1Ab (42,12%) e com menor porcentagem de representantes da subclasse cry1Db (0,6%). Nos bioensaios observou-se 100% de mortalidade para lagartas de P. xylostella com os isolados utilizados, indicando que combinações de tipos diferentes de genes cry1 apresentam ação tóxica para larvas de P. xylostella. Analisando a estrutura populacional de B. thuringiensis foram obtidos 78 haplótipos, definidos para as populações das diferentes coleções, e 76 haplótipos, definidos para as populações de diferentes regiões brasileiras, retratando a variabilidade genética para os loci hblA, plcR, nheBC e cry1 analisados. Segundo valores FSTs, de comparação duas a duas, diferenças significativas entre coleções e populações de B. thuringiensis provenientes das regiões brasileiras foram verificadas. Mesmo assim, alguns grupos formados são constituídos por uma população clonal de isolados da bactéria. / The work was developed in the Laboratory of Bacterias’ Genetics and Applied Biotechnology (LGBBA) at UNESP/ Jaboticabal Campus. There were genetically characterized, by PCR, isolates of B. thuringiensis, belonging to three Brazilian collections basead on cry1 gene content, evaluating their effects on Plutella xylostella. They were also characterized concerning their enterotoxins production such as HBL, NHE and the PLC virulence factor, using molecular techniques, so as to evaluate their gene diversities, as well as their population genetic, using the PCR-RFLP approach. It was observed a homogeneous distribution of the cry1 subclasses within B. thuringiensis strain collections studied, with bigger percentage of isolates showing the cry1Ab genes (42.12%) and with lower percentage of isolates for subclass cry1Db (0.6%). The bioassays have revealed 100% mortality to P. xylostella larvae meaning that the effectiveness of B. thuringiensis as a biological control agent does not depend at the cry genes content. When the B. thuringiensis population structure was considered, 78 haplotypes were defined for the strains contents of different collections and 76 haplotypes were defined for strains of different Brazilian regions, exhibiting the great genetic variability for hblA, plcR, nheBC and cry1 loci. According to the FSTs values for establish pair comparisons, significant differences among the B. thuringiensis collections and populations, were observed. Nevertheless some of the formed groups were considered as bacterial clonal population.
194

Desenvolvimento de clones de cajazeiras sobre diferentes porta-enxertos e diversidade genética de acessos quanto a compostos bioativos nas cascas e folhas / Development of yellow mombin clones onto different rootstocks and diversity of genetic accessions as to the bioactive compounds in the bark and leaves

Ramires, Christiane Mendes Cassimiro 03 March 2016 (has links)
Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-03-02T14:51:05Z No. of bitstreams: 1 ChristianeMCR_TESE.pdf: 1824459 bytes, checksum: 8d67db5817b6096ad2d44e2a3043a10d (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-03-21T15:02:11Z (GMT) No. of bitstreams: 1 ChristianeMCR_TESE.pdf: 1824459 bytes, checksum: 8d67db5817b6096ad2d44e2a3043a10d (MD5) / Made available in DSpace on 2017-03-21T15:02:28Z (GMT). No. of bitstreams: 1 ChristianeMCR_TESE.pdf: 1824459 bytes, checksum: 8d67db5817b6096ad2d44e2a3043a10d (MD5) Previous issue date: 2016-03-03 / Emepa - Empresa Estadual de Pesquisa Agropecuária / The social and economic importance of yellow mombin is due to the marketing of its raw fruits and derivatives. The non-existence of commercial clones and the high plant size are the main obstacles to its rational cultivation being necessary to make the cloning a viable instrument through the interspecific rootstocks in order to downsize the plants heights. Studies done with yellow mombin grafted onto rootstocks of yellow mombin and hog-plum did not markedly downsize the plant height but these clones were not evaluated in other enviroments. The yellow mombin shows potential for remedies. In the pharmaceutical industry it is used as phytotherapics against the Herpes virus. In works done with this species some bioactive compounds were found in the leaves such as flavonoids and tannins. Although this potential, some researches on chemical characterization and genetic diversity among genotypes are incipient. The objective of this study was to evaluate the vegetative growth of yellow mombin clones grafted onto interspecific rootstocks in different environments and the genetic diversity as to bioactive compounds among accessions of the Emepa-PB´s germplasm bank. In order to evaluate the clones development two trials with a completely randomized block design were performed. The trial 1 was conducted in a 3 x 4 x 3 factorial design with four repetitions, totaling 36 treatments, being three different interspecific rootstocks with yellow mombin (S. mombin), hog-plum (S. tuberosa) and coarse mombin (S. venulosa), four graftings of yellow mombin clones (Itaitinga, Gereau, Lagoa Redonda and Genipabu) and three different places (João Pessoa, PB, Ipanguaçu, RN and Itabuna, BA). The trial 2 was conducted in a 4 x 3 factorial design, with four repetitions, totaling 12 treatments. Three graftings of yellow mombin (Emepa 8.2, Emepa 8.6 and Emepa 20) obtained from the grafting between yellow mombin clones, grafted onto yellow mombin, plus one genotype of ungrafted yellow mombin, were used in the same places. The evaluated variables for the two trials at the 8, 39 and 46 months old were plant height, stem circumference, crown spread, crown format, number of branches and percentage of dead plants. The conclusions are that the environment, the grafting and the rootstocks did not influence the size and vigor of the clones allowing the identification of the morphological characteristics variations in each environment; that in Trial 1, for the three enviroments, the graftings of yellow mombin onto yellow mombin, hog-plum and coarse mombin rootstocks did not form clones with ideal sizes so that they cannot be recommended for commercial plantation; that in Trial 2, in the three enviroments, the Emepa 8.2 showed smaller size, bigger crown spread, major number of branches, 100% crown in a spread format and it can be recommended for new studies and later multiplication for commercial plantation. Leaves and barks of 27 yellow mombin accessions of the Emepa´s germplasm bank, in João Pessoa, PB, were used. The extractions were performed with methanol and the identification and quantification of bioactive compounds were checked through the High-Performance Liquid Chromatography (HPLC). For the grouping of accessions were used the Principal Components Analysis (PCA) and the UPGMA method. The standardized Euclidean distancewas used as a measure of genetic diversity. Rutin, quercetin, ellagic acid and geraniin compounds were quantified in leaves and ellagic acid and geraniin compounds were quantified inbarks. The highest amounts were found in leaves. Seven groups were formed. The accession group A3 was the most divergent with high amounts of rutin, quercetin and ellagic acid in leaves. The conclusion is that there is variability among accessions and it must be preserved and exploited through the genetic improvement programs / A importância socioeconômica da cajazeira é devido à comercialização dos frutos e do consumo de seus derivados. A inexistência de clones comerciais e o porte alto da planta constituem-se em entraves ao seu cultivo racional, necessitando viabilizar a clonagem com porta-enxertos interspecíficos visando reduzir o porte das plantas. Estudos realizados com a cajazeira enxertada na própria espécie e em umbuzeiro não demonstraram a diminuição significativa do porte da planta. No entanto, esses clones não foram avaliados em outros ambientes. A cajazeira apresenta potencial para medicamentos. Na indústria farmacêutica é utilizada como fitoterápico contra o vírus do Herpes. Em trabalhos realizados por outros pesquisadores, foram identificados compostos bioativos nas folhas tais como flavonoides e taninos. Apesar desse potencial, as pesquisas sobre a caracterização química e a divergência genética entre os genótipos são incipientes. O objetivo deste trabalho foi avaliar o desenvolvimento de clones de cajazeira enxertados sobre porta-enxertos interespecíficos em diferentes ambientes e a diversidade genética quanto a compostos bioativos entre acessos do banco de germoplasma da Emepa-PB. Para avaliação do desenvolvimento dos clones, foram realizados dois ensaios em delineamento inteiramente casualizado. O Ensaio 1 foi conduzido em esquema fatorial 3 x 4 x 3, com quatro repetições, totalizando 36 tratamentos, sendo três porta-enxertos interespecíficos com cajazeira (S. mombin), umbuzeiro (S. tuberosa) e cajazeira-grande (S. venulosa), quatro enxertos de clones de cajazeira (Itaitinga, Gereau, Lagoa Redonda e Genipabu), e três locais (João Pessoa, PB, Ipanguaçu, RN e Itabuna, BA). O Ensaio 2 foi conduzido em esquema fatorial 4 x 3, com quatro repetições, totalizando 12 tratamentos. Foram utilizados três exertos de acessos de cajazeira (Emepa 8.2, Emepa 8.6 e Emepa 20) enxertados sobre cajazeira, mais um pé-franco de cajazeira, nos mesmos locais. As variáveis avaliadas, aos 8, 39 e 46 meses de idade, para os Ensaios 1 e 2, foram altura de planta, perímetro de caule, largura e formato de copa, número de ramos e mortalidade de plantas. Concluiu-se que o ambiente, os enxertos e os porta-enxertos de espécies de Spondias influenciaram no desenvolvimento dos clones, permitindo identificar variabilidade nas características morfológicas em cada ambiente; no Ensaio 1, nos três ambientes, a enxertia da cajazeira sobre porta-enxertos de cajazeira, cajazeira-grande e umbuzeiro não formaram clones com porte ideal para recomendação comercial; no Ensaio 2, nos três ambientes, o clone Emepa 8.2 apresentou menor porte, maior largura de copa, maior número de ramos e 100% de formato de copa esgalhada, podendo ser recomendado para novos estudos e posterior multiplicação para exploração comercial. Para avaliação da diversidade genética, foram utilizadas folhas e cascas de cajazeira de 27 acessos do banco de germoplasma da Emepa, em João Pessoa, PB. As extrações foram realizadas com metanol e a quantificação foi determinada por Cromatografia Líquida de Alta Eficiência (CLAE). Para o agrupamento dos acessos utilizou-se a Análise de Componentes Principais (ACP) e o método aglomerativo UPGMA. Foi utilizada a distância euclidiana média padronizada como medida de dissimilaridade genética. Foram quantificados nas folhas os compostos rutina, quercetina, ácido elágico e geraniina e foram quantificados nas cascas os compostos ácido elágico e geraniina. Os maiores valores foram obtidos nas folhas. Foram formados 7 grupos. O acesso A3 foi o mais divergente com valores elevados de rutina, quercetina e geraniina nas folhas. Concluiu-se que há variabilidade entre os acessos e que esta deve ser preservada e explorada em programas de melhoramento genético / 2017-02-24
195

Genetická variabilita entomopatogenních hub rodu \kur{Isaria} v České republice / Genetic variability of \kur{Isaria} genus in Czech Republic

ČÁPOVÁ, Aneta January 2015 (has links)
My diploma thesis deals with genetic variability of entomopathogenic fungi of the Isaria genus encountered in the Czech Republic. Individual representative of the genus can be found in soil where they attack all developmental stages of insects, giving preference to larvae and pupae. The Isaria fungi find application first and foremost where plants have to be provided biological protection. In case of mitosporic fungi is the precise identification very difficult, taxonomy is often unclear in many genera, including the genus Paecilomyces/Isaria to demonstrate their polyphyletic nature. The fungi are classified primarily with reliance on morphological studies. The most common markers used to identify fungi are the shapes and sizes of their conidia and the biological properties (germination of spores, tests of biological efficiency). Identification made in consideration of the morphological markers is inaccurate and very variable. To overcome those accuracies, there are very useful molecular DNA markers, which can be relevant in ecology, biology and in fungi genetics. This paper relies on applying the ITS region (Internal Transcribed Spacer) as a molecular marker. ITS regions are partial constituent rDNA carrying no code - that is why the regions are likely to accumulate evolutionary changes in the DNA sequence, which makes them suitable for extensive use in taxonomic analyses of many organisms. The study results in a phylogenetic trees constructed by comparing different sequences of ITS regions obtained from the samples of entomopathogenic fungi of the Isaria genus gathered in the Czech Republic during the monitoring stage 2013 to 2014. Thereunder detection of Isaria sp. occurring in the Czech Republic.
196

Detecção, caracterização molecular e diversidade genética de begomovirus que infectam fava (Phaseolus lunatus L.) / Detection, molecular characterization and genetic diversity of the begomovirus the infect lima bean (Phaseolus lunatus)

Silva, Sarah Jacqueline Cavalcanti da 29 March 2006 (has links)
Lima bean (Phaseolus lunatus L.) is one of the four major important grain legumes in Brazil. The occurrence of diseases has difficulted its culture and has affected grain quality of this crop. Among the most important diseases are the viruses, especially those generated from Geminivirus. The high severity of the Geminiviruses diseases is especially due to both the absence of pathogen resistance varieties and increase in the population of a new biotype (biotype B), of the insect vector, commonly named whitefly (Bemisia tabaci). This biotype transmitis the virus more efficiently and it presents a host range larger than biotype A. The present estudy objected the detection, molecular characterization and analisys of the genetic diversity of Begomovirus isolates that infects lima bean plats in Alagoas and Pernambuco States. The detection was realized by PCR technique utilizing as a mold DNA extracted from plants presenting symptoms of geminivirus infection which were colleted from seven locations of Alagoas and one of Pernambuco. It was identified Begomovirus infection in seventeen collected samples. The analisys of genetic diversity, based in PCR-RFLP, revealed that exists diversity among the isolates of Begomovirus that were infecting these plants. According to differences in the patterns of bands generated by PCR-RFLP, it was chosen three isolates (fava Maceió, fava Recife and fava União dos Palmares), in an attempt to sequence analysis. The comparison of the obtained sequences with other deposited in GenBank/NCBI allowed the classification of these isolates as Bean golden mosaic virus, the last one being the first report of infection caused this species in lima bean plants in Alagoas and Pernambuco State. / Fundação de Amparo a Pesquisa do Estado de Alagoas / A fava (Phaseolus lunatus L.) está entre as quatro espécies de leguminosas de grãos mais importantes no Brasil. A ocorrência de doenças tem dificultado o cultivo e afetado a qualidade dos grãos dessa cultura. Entre as doenças mais importantes, estão as viroses, destacando-se aquelas ocasionadas por Geminivirus. A alta severidade das doenças causadas por geminivírus, deve-se principalmente à ausência de variedades resistentes ao patógeno e também ao aumento populacional de um novo biótipo (biótipo B) do inseto vetor, vulgarmente denominado, "mosca branca" (Bemisia tabaci). Este biótipo transmite o vírus mais eficientemente e apresenta uma gama de hospedeiros mais ampla do que o biótipo A. O presente trabalho teve como objetivos principais a detecção, caracterização molecular e a análise da diversidade genética de isolados de Begomovirus que infectam plantas de fava no Estado de Alagoas e Pernambuco. A detecção foi realizada mediante a técnica de PCR utilizando como molde o DNA extraído de plantas com sintomas de infecção por geminivírus, coletadas em sete municípios de Alagoas e em um de Pernambuco. Foi diagnosticada infecção por Begomovirus em dezessete amostras coletadas. A análise da diversidade genética, baseada em PCR-RFLP, demonstrou que existe diversidade entre os isolados de begomovírus que estavam infectando estas plantas. A partir das diferenças nos padrões de bandas gerados através da PCR-RFLP, foram escolhidos três isolados (Fava Maceió, Fava Recife e Fava União dos Palmares), para fins de seqüenciamento. A comparação das seqüências obtidas, com outras seqüências depositadas do GenBank/NCBI permitiu a classificação desses isolados como Bean golden mosaic virus, sendo este o primeiro relato de infecção por esta espécie em plantas de fava, nos estados de Alagoas e Pernambuco.
197

Análise de espécies de Curvularia associadas à cultura do inhame no estado de Alagoas / Analysis of species of Curvularia associated with yam in Alagoas state

Moraes, Edlene Maria da Silva 25 September 2009 (has links)
The yam (Dioscorea cayennensis Lam.) is an important staple crop in the Northeast region of Brazil, mainly in the states of Alagoas, Pernambuco, and Paraíba, the highest producing areas in the region. The crop is affected by pathogens that reduce yield and leaf blight, caused by the fungus Curvularia eragrostidis, can cause considerable crop losses. In the socio-economic context in which this crop is placed, the use of resistant varieties is the most effective control strategy. However, for this strategy to be successful, knowledge of the genetic variability of the pathogen is required. Samples of infected yam leaves were collected in 2005 and 2008, from fields in Chã Preta, Paulo Jacinto, and Viçosa and 73 isolates were obtained. Based on morphological characteristics all isolates were identified as C. eragrostidis. All isolates were pathogenic to yam and there were differences in the values of area under the disease progress curve (P= 0.02). When different isolates were paired in culture, mycelia compatibility in the majority of pairings. Similarity and phylogenetic analyses supported the identification of the species associated to yam leaf blight. The AFLP markers were used to investigate the genetic structure of the population of C. eragrostidis. Gene diversity was high (Ht = 0.31) and there was low differentiation between populations (Gst = 0.06). The population was not structured according to geographical origin. The genetic variability within populations of C. eragrostidis was high. / Fundação de Amparo a Pesquisa do Estado de Alagoas / O inhame (Dioscorea cayennensis Lam.) é cultura importante no Nordeste do Brasil, principalmente nos estados de Alagoas, Pernambuco e Paraíba, que se destacam como os maiores produtores. A cultura é afetada por patógenos que reduzem a produtividade. A queima das folhas, causada pelo fungo Curvularia eragrostidis, pode causar perdas significativa de produção. Considerando o contexto sócio-econômico no qual se insere a cultura do inhame, o plantio de variedades resistentes é a estratégia mais adequada de controle da queima foliar. Contudo, o sucesso desta estratégia depende, entre outros fatores, do conhecimento da variabilidade genética do patógeno. Nos anos de 2005 e 2008, coletaram-se amostras de folhas afetadas nos municípios de Chã Preta, Paulo Jacinto e Viçosa e 73 isolados foram obtidos e baseado em características morfológicas, foram identificados como C. eragrostidis. Todos os isolados utilizados no teste de patogenicidade foram patogênicos e houve variação quanto aos valores de AACPD ( P=0,02). Quando diferentes isolados foram pareados em meio de cultura, a maioria mostrou reação de compatibilidade micelial. Análises de similaridade e filogenéticas confirmaram a identificação da espécie associada à queima foliar do inhame. O marcador molecular AFLP foi utilizado com o objetivo de determinar a estrutura genética da população de C. eragrostidis. A diversidade gênica total foi alta (Ht =0,31) com baixa diferenciação entre as populações (Gst = 0,06). Não foi detectada estruturação da população conforme os municípios. A variabilidade genética dentro das populações de C. eragrostidis estudada foi alta.
198

Caracterização molecular da estrutura genética de populações e espécies camarões palemonídeos Macrobrachium do gênero Macrobrachium

Guerra, Ana Letícia [UNESP] 05 August 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-05Bitstream added on 2014-06-13T18:29:24Z : No. of bitstreams: 1 guerra_al_me_sjrp.pdf: 4594193 bytes, checksum: 441ad838c49d255aeb995cc415bbc92e (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os camarões do gênero Macrobrachium pertencem à família Palaemonidae. Habitam as proximidades do litoral e, também, ambientes de água doce. Com mais de cem espécies amplamente distribuídas pelas regiões tropicais e subtropicais do mundo, os palemonídeos possuem hábitos crípticos e noturnos. Particularmente na região noroeste do Estado de São Paulo, podemos encontrar várias espécies com importância econômica e ecológica consideráveis. Entretanto, existem poucos estudos na literatura relacionados ao conhecimento da biologia desses crustáceos. Assim, o presente trabalho objetivou analisar a variabilidade genética intra e interpopulacional, de amostras de duas espécies de camarões palemonídeos do gênero Macrobrachium (M. amazonicum e M. jelskii), coletadas em diferentes localidades, utilizando-se a análise das seqüências dos genes mitocondriais COI e rRNA 16S e, ainda, devido à problemática taxonômica existente entre essas duas espécies, também foi analisada a variabilidade genética interespecífica, utilizando-se os mesmos genes.. O cálculo dos índices de divergência genética intrapopulacionais apresentou valores baixos, refletindo uma provável estruturação genética destas populações. Apenas as populações de MjME e do CAUNESP apresentaram valores de divergência genética mais elevados, sugerindo um desequilíbrio na estruturação genética das mesmas, provavelmente causado por interferência antrópica e situação de cativeiro, respectivamente. Nas comparações interpopulacionais, envolvendo M. amazonicum, as taxas de divergência genética apresentaram uma ampla variação, também com média elevada. Os valores elevados nas comparações envolvendo a população do CAUNESP, permitiram descartar a hipótese da provável origem comum das populações de Macrobrachium, a partir de espécimes trazidos do Pará. Da mesma forma, as comparações... / The genus Macrobrachium (Bate, 1868) belongs to the Palaemonidae family. Their species are widely distributed in lakes, floodplains and rivers in tropical and subtropical regions of South America, having cryptic and nights habits. This genus presents nearly 210 known species with ecological and economic importance. Particulary in the northwestern state of São Paulo, we can find several species with considerable importance. However, there are few studies related to knowledge of the biology of these crustaceans. The aim this work was to analyze the genetic variability interpopulation, and interspecific of two Macrobrachium species (M. amazonicum and M. jelskii), using the mitochondrial gene sequence COI and 16S rRNA. Also, due to taxonomic problems between these two species we analyzed interspecific genetic variability, using the same genes. The intrapopulation rates of genetic divergence values were low, reflecting a probable genetic structure of these populations. Only populations MjME and CAUNESP showed higher divergence values, suggesting changes in their genetic structure of the same, probably caused by human interference and situation of captivity, respectively. In comparisons inferences involving M. amazonicum, rates of genetic divergence showed a wide range, also with high average. High values in comparisons involving the population of CAUNESP, allowed to reject the hypothesis of a probable common origin of populations the Macrobrachium specimens brought from State of Para. Interpopulation comparisons involving M. jelskii also showed high values of divergence, especially for the population collected from the Mendonça dam, whose genetic alteration in population structure was attributed to the frequent introduction of exotic specimens. The values of interspecific genetic divergence in the samples collected in the same geographic location were low for populations Adolfo (0.3%) ...(Complete abstract click electronic access below)
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Variação genética para caracteres silviculturais em banco ativo de germoplasma de espécies arbóreas do cerrado e da floresta estacional semidecidual

Rodrigues, Carlos José [UNESP] 27 August 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-27Bitstream added on 2014-06-13T20:26:27Z : No. of bitstreams: 1 rodrigues_cj_dr_ilha.pdf: 1658043 bytes, checksum: 2ad97ce0bc47360910cd7c904ad1c71d (MD5) / A construção da Usina Hidrelétrica Engenheiro Sergio Motta, na região do Pontal do Paranapanema, promoveu severos impactos aos ambientes naturais, especialmente sobre as comunidades florestais remanescentes. Com a finalidade de compensar a perda das espécies florestais na área de inundação do reservatório, desenvolveu-se por meio do convênio CESP – ESALQ/USP-IPEF, o Projeto Banco Ativo de Germoplasma (BAG), implantando-se em forma de teste de progênies, delineamento de blocos ao acaso, constituído por três repetições, contendo parcelas lineares de oito plantas de trinta progênies de cada uma das espécies eleitas para conservação. O presente estudo objetivou verificar o comportamento, variação genética e propor estratégia adequada de seleção para caracteres silviculturais de 32 espécies do Banco Ativo de Germoplasma de espécies de Floresta Estacional Semidecidual (BAG – SP), implantado em Rosana – SP e de 31 espécies conservadas no Banco Ativo de Germoplasma de espécies do Cerrado (BAG - MS), implantado em Anaurilândia – MS. Foram avaliados os caracteres DAP (diâmetro a altura do peito), altura e sobrevivência. Os resultados, obtidos por meio do programa estatístico SELEGEN-REML/BLUP, possibilitaram observar que o sistema de plantio adotado na implantação do Banco Ativo de Germoplasma da Floresta Estacional Semidecidual (BAG – SP) e do Banco Ativo de Germoplasma do Cerrado (BAG - MS), mostra-se promissor para as espécies que se encontram conservadas nestes. Aos 9,3 anos após o início da implantação o BAG – SP apresenta, em média, 67,5% de sobrevivência, DAP de 5,42 cm e 5,73 m de altura. Aos 8,3 anos após o início da implantação o BAG – MS apresenta, em média, 65% de sobrevivência, DAP de 7,51 cm e 5,79 m de altura. A variação genética presente nas populações que compõe o... / The construction of the Hydroeletric Power Plant Engenheiro Sergio Motta; in the region of Pontal do Paranapanema, caused severe impacts to natural environments, especially on the remaining forest communities. To compensate the loss of forest species in the floodplain of the reservoir, was developed, through the partnership CESP – ESALQ/ USP-IPEF, the Project Active Germplasm Bank (AGB), implemented in the form of a progeny test, designed random blocks, consisting of three replicates, containing linear parcels of eight plants from thirty progenies of each one of the elected species for conservation. This work aimed to study the genectic variation for the silvicultural characters of 32 species from the Active Germplasm Bank of species of Semideciduous Seasonal Forest (AGB – SP), implemented in Rosana – SP and 31 species conserved in the Active Germplasm Bank of Cerrado species (AGB-MS), implemented in Anaurilândia – MS. Were evaluated the DBH (diameter at breast height), height and survival. The results obtained through the statistical program SELEGEN-REML/BLUP, allowed to observe that the plantation system adopted in the implementation of the Active Germplasm Bank of the Semideciduous Seasonal Forest (AGB-SP) and the Active Germplasm Bank of Cerrado (AGB-MS) shows promise for the species that are conserved in these. At 9.3 years after the beginning of the implementation, the AGB – SP showed 67.5% of survival, DBH of 5.42 cm and 5.73 m of height and the AGB-MS, at 8.3 years after the beginning of the implementation showed 65% of survival, DBH of 7.51cm and 5.79 m of height. The genetic variation present in populations that make up the AGBSP and AGB-MS validates the ex situ conservation program that was proposed and enables the development of an improving program for these species, in order to produce improved seeds. The strategy... (Complete abstract click electronic access below)
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Effet des restaurations des écosystèmes, de la trophie et de la connectivité hydrologique sur la diversité génétique des plantes aquatiques / Impact of ecosystem restorations, trophy and hydrologic connectivity on aquatic plant genetic variability

Oudot-Canaff, Jehanne 06 February 2014 (has links)
La conservation des zones humides fortement modifiées par les pratiques anthropiques, nécessite l’acquisition de données scientifiques sur leur diversité et leur fonctionnement. Cette thèse vise à relier l’anthropisation des zones humides à la diversité génétique, niveau de base de la biodiversité lié à la capacité adaptative des populations et au maintien des espèces. L’effet de l’anthropisation sur la diversité génétique de végétaux aquatiques est étudié à plusieurs échelles d’espaces (zone humide et bassin versant) et de temps (études synchroniques et diachroniques). La diversité génétique de populations de deux espèces rudérales (Berula erecta et Apium nodiflorum) et une compétitive (Nuphar lutea) est comparée dans deux plaines alluviales contrastées (trophie, connectivité hydrologique et restauration), à l’aide de marqueurs microsatellites adaptés à l’étude d’espèces clonales. La diminution de la connectivité hydrologique augmente la différenciation génétique et diminue la diversité génétique pour les espèces rudérales étudiées alors qu’elle n’a pas d’effet sur l’espèce compétitive. L’impact de la connectivité est donc dépendant de la stratégie de reproduction. La diversité génétique des espèces rudérales diminue également dans les zones humides plus eutrophes. L’augmentation de la diversité génétique post-restauration chez B. erecta est corrélée à la fréquence des perturbations (assecs) qui créent des niches favorisant le recrutement des graines. Cette étude propose des préconisations de gestion pour les zones humides et apporte des connaissances sur la dynamique de la diversité génétique des plantes aquatiques en lien avec leur environnement / The conservation of wetlands which are strongly modified by human practices, requires the acquisition of knowledge about their diversity and functioning. This thesis aimed to link the human pressures and plant genetic diversity in wetlands, which is the basic level of biodiversity linked to the adaptive capacity of populations and species maintenance. The effect of anthropization on the genetic diversity of aquatic plants is studied at several spatial and temporal scales (wetland and watershed; synchronic vs. diachronic studies). The genetic diversity of populations of two ruderal (Berula erecta and Apium nodiflorum) and one competitive species (Nuphar lutea) in two contrasting floodplains (in terms of trophic status, hydrological connectivity and restoration) is compared using microsatellite markers suitable for the study of clonal species. A reduction in hydrological connectivity increases genetic differentiation and decreases genetic diversity for ruderal species studied, while it did not affect the competitive species. The impact of connectivity is related to plant reproductive strategy. The genetic diversity of ruderal species also decreases in most eutrophic wetlands. The increase of genetic diversity of B. erecta after restoration is correlated with the frequency of disturbances (dewatering) that create niches for seed recruitment. This study provides management recommendations for the impacted wetlands and provides knowledge about the dynamics of the genetic diversity of aquatic plants in relation to their environment

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