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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.
1

DNA barcoding of different earthworms' species and their response to ecotoxicological testing / Laetitia Voua Otomo

Voua Otomo, Laetitia January 2015 (has links)
The ecotoxicological literature reveals that countless researchers worldwide rely upon informally identified commercial earthworm stocks for laboratory bioassays. The primary aim of this study was to investigate laboratory and commercial stocks of Eisenia species used in South Africa in order to confirm their taxonomy, assess their levels of genetic richness and differentiation. To do so, populations of potential Eisenia andrei and Eisenia fetida were purchased/obtained from vermiculturists and laboratories from four provinces of South Africa. DNA barcoding was used to investigate these taxonomic uncertainties. The COI gene was partially amplified and sequenced in selected earthworms from eight local populations (focal groups) and two European laboratory stocks (non-focal groups). Only nine COI haplotypes were identified from the 224 sequences generated. One of these haplotypes was found to belong to the Megascolecidae Perionyx excavatus. The remaining eight haplotypes belonged to the genus Eisenia although only a single Eisenia fetida haplotype, represented by six specimens, was found in one of the European populations. The other seven haplotypes, all occurring in South Africa, were Eisenia andrei. No Eisenia fetida was found in the South African based populations. One of the commercial stocks from South Africa and a laboratory culture from Europe were mixes of E. andrei - P. excavatus and E. andrei – E. fetida respectively. COI haplotype numbers were limited to two to three distinct sequences within each of the local groups. This translated into a haplotype diversity (H) lower than 0.45 in all the populations, which is very low when compared to other such earthworm studies in which COI polymorphism has been investigated. Of all the local populations investigated, only the lone field population included was genetically divergent from the other populations. This was explained by the haplotype distribution across the populations which indicated that this population was the only one not harbouring the haplotype which represented 75% or more of the COI sequences within the local populations. Because research suggests that earthworm populations with limited genetic diversity may suffer inbreeding depression which could affect traits such as reproduction and survival, the secondary aim was to test whether metal-sensitive earthworms were overly present in the populations investigated. To do so, the three most common COI haplotypes identified between the 8 local populations of E. andrei (called Hap1, Hap2 and Hap3) were paired up and exposed to cadmium. A total of six couples were exposed to 0, 25, 50 and 100 mg Cd/kg for 4 weeks at 20ºC. The survival, biomass variation, cocoon production and cocoon hatching success were assessed for all the couples. The results indicated that couple 6 (Hap3xHap3) was the most sensitive for three of the endpoints assessed whereas couple 4 (Hap1 x Hap3) was the least sensitive. Cocoon hatching success could not help differentiate the couples. The analysis of Cd tissue contents revealed that with increasing Cd concentration, Cp6 (Hap3xHap3) could accumulate significantly more Cd than any other couple (p ≤ 0.01). These findings indicate that earthworm populations may carry intrinsically metal-tolerant and metal-sensitive genotypes. In the context of ecotoxicological testing, the present results underline the importance of using genetically diverse populations in laboratory testing as Cp6 (Hap3xHap3) could have suffered from the deleterious effect of inbreeding. Because E. fetida could not be found in the local populations assessed, it is recommended that further earthworm DNA barcoding studies, covering a more representative geographical area of South Africa and including more field populations of Eisenia spp. be conducted. Because of the occurrence of genetic homogeneity in the populations studied, it is suggested that captive breeding initiatives be established using specimens obtained from several geographically distant field and reared populations. Further research investigating patterns of Cd accumulation/excretion kinetics between the Cd-tolerant and Cd-sensitive individuals reported in the present study, should be conducted to help determine whether inbreeding is the sole factor explaining the observed genotypic responses to Cd. Finally, the necessity of a standardised earthworm barcoding protocol that could help both to properly identify laboratory earthworm stocks and to select genetically diverse stocks suitable for laboratory testing, is discussed together with the relevance of the present work to ecotoxicological testing in general. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
2

DNA barcoding of different earthworms' species and their response to ecotoxicological testing / Laetitia Voua Otomo

Voua Otomo, Laetitia January 2015 (has links)
The ecotoxicological literature reveals that countless researchers worldwide rely upon informally identified commercial earthworm stocks for laboratory bioassays. The primary aim of this study was to investigate laboratory and commercial stocks of Eisenia species used in South Africa in order to confirm their taxonomy, assess their levels of genetic richness and differentiation. To do so, populations of potential Eisenia andrei and Eisenia fetida were purchased/obtained from vermiculturists and laboratories from four provinces of South Africa. DNA barcoding was used to investigate these taxonomic uncertainties. The COI gene was partially amplified and sequenced in selected earthworms from eight local populations (focal groups) and two European laboratory stocks (non-focal groups). Only nine COI haplotypes were identified from the 224 sequences generated. One of these haplotypes was found to belong to the Megascolecidae Perionyx excavatus. The remaining eight haplotypes belonged to the genus Eisenia although only a single Eisenia fetida haplotype, represented by six specimens, was found in one of the European populations. The other seven haplotypes, all occurring in South Africa, were Eisenia andrei. No Eisenia fetida was found in the South African based populations. One of the commercial stocks from South Africa and a laboratory culture from Europe were mixes of E. andrei - P. excavatus and E. andrei – E. fetida respectively. COI haplotype numbers were limited to two to three distinct sequences within each of the local groups. This translated into a haplotype diversity (H) lower than 0.45 in all the populations, which is very low when compared to other such earthworm studies in which COI polymorphism has been investigated. Of all the local populations investigated, only the lone field population included was genetically divergent from the other populations. This was explained by the haplotype distribution across the populations which indicated that this population was the only one not harbouring the haplotype which represented 75% or more of the COI sequences within the local populations. Because research suggests that earthworm populations with limited genetic diversity may suffer inbreeding depression which could affect traits such as reproduction and survival, the secondary aim was to test whether metal-sensitive earthworms were overly present in the populations investigated. To do so, the three most common COI haplotypes identified between the 8 local populations of E. andrei (called Hap1, Hap2 and Hap3) were paired up and exposed to cadmium. A total of six couples were exposed to 0, 25, 50 and 100 mg Cd/kg for 4 weeks at 20ºC. The survival, biomass variation, cocoon production and cocoon hatching success were assessed for all the couples. The results indicated that couple 6 (Hap3xHap3) was the most sensitive for three of the endpoints assessed whereas couple 4 (Hap1 x Hap3) was the least sensitive. Cocoon hatching success could not help differentiate the couples. The analysis of Cd tissue contents revealed that with increasing Cd concentration, Cp6 (Hap3xHap3) could accumulate significantly more Cd than any other couple (p ≤ 0.01). These findings indicate that earthworm populations may carry intrinsically metal-tolerant and metal-sensitive genotypes. In the context of ecotoxicological testing, the present results underline the importance of using genetically diverse populations in laboratory testing as Cp6 (Hap3xHap3) could have suffered from the deleterious effect of inbreeding. Because E. fetida could not be found in the local populations assessed, it is recommended that further earthworm DNA barcoding studies, covering a more representative geographical area of South Africa and including more field populations of Eisenia spp. be conducted. Because of the occurrence of genetic homogeneity in the populations studied, it is suggested that captive breeding initiatives be established using specimens obtained from several geographically distant field and reared populations. Further research investigating patterns of Cd accumulation/excretion kinetics between the Cd-tolerant and Cd-sensitive individuals reported in the present study, should be conducted to help determine whether inbreeding is the sole factor explaining the observed genotypic responses to Cd. Finally, the necessity of a standardised earthworm barcoding protocol that could help both to properly identify laboratory earthworm stocks and to select genetically diverse stocks suitable for laboratory testing, is discussed together with the relevance of the present work to ecotoxicological testing in general. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
3

História Demográfica e Estrutura de Populações para a Espécie Cactófila Drosophila meridionalis. / Demographic History and Population Structure for the Cactophilic Species Drosophila meridionalis.

Leal, Dora Yovana Barrios 01 March 2013 (has links)
Drosophila meridionalis é uma espécie endêmica da América do Sul, sendo amplamente distribuída na Costa Atlântica do Brasil. Com o objetivo de elaborar uma hipótese filogeográfica para esta espécie foram obtidas sequências do gene nuclear period e do gene mitocondrial COI. Foram calculados os índices de diversidade nucleotídica e realizados os testes: AMOVA, testes de neutralidade, a Mismatch Distribution, Bayesian Skyline Plot, NCPA. Foram obtidas três redes pelo gene COI, denominadas A (populações do interior), B (populações do litoral sul) e C (populações do litoral sudeste e oriental) e uma única rede obtida para o gene period, esta rede divide as populações em dois grupos sendo o primeiro congruente com a rede A e o segundo compreendendo as redes B e C, do gene COI. A AMOVA mostrou uma estruturação alta e significativa entre as populações do interior e o litoral para os dois genes (ct=0,72 gene COI; ct=0,70 gene period), que pode ser explicada pela presença de barreiras geográficas, como a Serra do Mar. Eventos de expansão populacional e de fluxo gênico restrito com isolamento por distância foram detectados nas populações do litoral e o interior respectivamente. A expansão da área de ocorrência de D. meridionalis provavelmente teve inicio com as populações do litoral do Rio Grande de Sul, em direção ao litoral de Santa Catarina com posterior colonização a longa distância dos estados de São Paulo, Rio de Janeiro e Bahia. Migrações assincrônicas de indivíduos de populações litorâneas de São Paulo e Santa Catarina provavelmente colonizaram o interior de São Paulo, e a partir destas populações, se iniciara uma expansão populacional em direção ao sul pelo interior, colonizando o Paraná e Rio Grande do Sul. A análise bayesiana (MCCT) indicou que o tempo do ancestral comum mais recente (TMRCA) para todos os haplótipos de D. meridionalis é de 81.700 anos atrás, data que marca a separação das populações do interior e do litoral aproximadamente no final do Pleistoceno. Eventos similares têm sido sugeridos para explicar a distribuição geográfica de espécies do cluster D. buzzatii, que ocorrem em simpatria em grande parte com populações de D. meridionalis. Esta espécie, como as espécies do cluster D. buzzatii, apresentou indicativos de flutuações demográficas, podendo estar associadas à expansão e contração da distribuição da vegetação xerofítica, durante as oscilações paleoclimáticas do Pleistoceno. / Drosophila meridionalis is an endemic species of South America, being widely distributed in the Atlantic Coast of Brazil. Aiming to develop a phylogeographic hypothesis for this species, sequences of mitochondrial COI and nuclear period genes were obtained. The diversity indexes, AMOVA, neutrality tests, Mismatch Distribution, Bayesan Skyline Plot and NCPA were calculated. We obtained three networks for the COI gene, denominated A (inland populations), B (south coast populations) and C (eastern and southeastern coast populations) and a single network obtained for the period gene, this network divides the population into two groups, being the first congruent with the network A of the COI gene and the second comprising the networks B and C of the COI gene. The AMOVA results, showed a high and significant structuring among inland and coastal populations, for both genes (ct=0,72 COI gene; ct=0,70 period gene), that can be explained by the presence of geographical barriers, such as Serra do Mar. Population expansion events and restricted gene flow with isolation by distance events were detected in coastal and inland populations respectively. The expansion of the area of occurrence of D. meridionalis probably was initiated with the populations of the coast of Rio Grande do Sul, towards the coast of Santa Catarina with subsequent long-distance colonization of the states of São Paulo, Rio de Janeiro and Bahia. Asynchronic migrations of individuals from coastal populations of São Paulo and Santa Catarina probably colonized the inland of São Paulo, and from these populations, a population expansion towards the south through the inland was initiated, colonizing the states of Paraná and Rio Grande do Sul. The bayesian analysis (MCCT) indicated that the time of the most recent common ancestor (TMRCA) for all haplotypes of D. meridionalis is from 81,700 years ago, a date that marks the separation of inland and coastal populations approximately at the end of the Pleistocene. Similar events have been suggested to explain the geographic distribution of species of the cluster D. buzzatii, occurring in sympatry largely with populations of D. meridionalis. This species, as the cluster D. buzzatii species, presented indicatives of demographic fluctuations, which can be associated with the expansion and contraction of the distribution of xerophytic vegetation, during the paleoclimatic fluctuations of the Pleistocene.
4

Use of molecular markers in biochemical taxonomy of Tischeriidae (Lepidoptera: Tischerioidea) and Elachistidae (Lepidoptera: Gelechioidea) / Molekulinių žymenų panaudojimas Tischeriidae (Lepidoptera: Tischerioidea) ir Elachistidae (Lepidoptera: Gelechioidea) drugių biocheminėje sistematikoje

Paulavičiūtė, Brigita 19 October 2010 (has links)
The field of molecular biology has expanded greatly in the last ten years and currently many entomologists want to use this technology since it is a new level of carrying out studies of insect ecological systems and taxonomy. The study of mitochondrial DNA (mtDNA) sequences has become the method for a wide range of taxonomic, population and evolutionary investigations in Lepidoptera (Lunt et al, 1996). The increasing popularity of molecular taxonomy will undoubtedly exert a major impact on conservation biology practice. The benefit of such approaches is undeniable since they will clearly be an asset to rapid biological assessments of poorly known taxa or unexplored areas, and to the discovery of cryptic biodiversity. The Tischeriidae and Elachistidae represent rather small families as compared to many other groups of Lepidoptera. Moths are with wingspan from 6–13 mm. They are found all over the world, but most species are known from Boreal, Palearctic and Neotropical regions. These moths are leaf-miners during all larval instars. Molecular tools can help to identify this group. A lot of Tischeriidae and Elachistidae species are siblings externally, and their identification is very problematic, so in this case the structure of the male genital is more popular. However, only two articles dealt with the results of the mitochondrial DNA analysis in Elachista species from Australia (Kaila and Ståhls, 2006) and Tisheria ptarmica from the United Arab Emirates (Nieukerken, 2010)... [to full text] / Molekuliniai žymenys yra polimorfinės DNR sekos lokalizuotos tam tikrose genomo vietose ir nustatomos naudojant įvairius molekulinės biologijos metodus. Jais nustatomi dviejų ar daugiau idividų ląstelėse esančios genetinės informacijos skirtumai. Morfologiniai žymenys naudojami ir šiandien, bet dėl įvairių trūkumų jų panaudojimas labai ribotas. Įvairūs molekuliniai tyrimo metodai vis dažniau naudojami entomologijoje (Loxdale, Lushai, 1998). Tiriant vabzdžių filogenezę ir sistematiką molekuliniai tyrimo metodai vis populiarėja, tačiau iki šiol jie nebuvo taikomi Tischeriidae ir Elachistidae šeimų drugių tokio pobūdžio tyrimuose. Šių šeimų drugiai filogenetiškai vieni primityviausių drugių būrio atstovai, jungiantys giminiškas šeimas. Tischeriidae ir Elachistidae drugiai plačiai paplitę tiek Baltijos regione, tiek visame pasaulyje, joms priklauso vieni mažiausių Žemėje mikro drugiai, kurie išsiskiria ne tik archaiška sandara, bet ir labai didele specializacija. Daugelio jų išskleistų sparnų ilgis tesiekia vos 6–13 mm. Daugelis Tischeriidae ir Elachistidae rūšių išoriškai yra panašios ir sunkiai atskiriamos, todėl pagrindinis dėmesys apibūdinant rūšį skiriamas patinų genitalijų struktūrai. Minuojantis gyvenimo būdas – svarbi primityvių Microlepidoptera biologinė adaptacija, suteikusi šiems vabzdžiams daug privalumų. Iki šiol molekulinių tyrimų su šiais drugiais atlikta ypač mažai, todėl visi publikuoti apžvalginiai darbai (tiek Lietuvos autorių, tiek užsienio mokslininkų), iki... [toliau žr. visą tekstą]
5

Molekulinių žymenų panaudojimas Tischeriidae (Lepidoptera: Tischerioidea) ir Elachistidae (Lepidoptera: Gelechioidea) drugių biocheminėje sistematikoje / Use of molecular markers in biochemical taxonomy of Tischeriidae (Lepidoptera: Tischerioidea) and Elachistidae Lepidoptera: Gelechioidea)

Paulavičiūtė, Brigita 19 October 2010 (has links)
Molekuliniai žymenys yra polimorfinės DNR sekos lokalizuotos tam tikrose genomo vietose ir nustatomos naudojant įvairius molekulinės biologijos metodus. Jais nustatomi dviejų ar daugiau idividų ląstelėse esančios genetinės informacijos skirtumai. Morfologiniai žymenys naudojami ir šiandien, bet dėl įvairių trūkumų jų panaudojimas labai ribotas. Įvairūs molekuliniai tyrimo metodai vis dažniau naudojami entomologijoje (Loxdale, Lushai, 1998). Tiriant vabzdžių filogenezę ir sistematiką molekuliniai tyrimo metodai vis populiarėja, tačiau iki šiol jie nebuvo taikomi Tischeriidae ir Elachistidae šeimų drugių tokio pobūdžio tyrimuose. Šių šeimų drugiai filogenetiškai vieni primityviausių drugių būrio atstovai, jungiantys giminiškas šeimas. Tischeriidae ir Elachistidae drugiai plačiai paplitę tiek Baltijos regione, tiek visame pasaulyje, joms priklauso vieni mažiausių Žemėje mikro drugiai, kurie išsiskiria ne tik archaiška sandara, bet ir labai didele specializacija. Daugelio jų išskleistų sparnų ilgis tesiekia vos 6–13 mm. Daugelis Tischeriidae ir Elachistidae rūšių išoriškai yra panašios ir sunkiai atskiriamos, todėl pagrindinis dėmesys apibūdinant rūšį skiriamas patinų genitalijų struktūrai. Minuojantis gyvenimo būdas – svarbi primityvių Microlepidoptera biologinė adaptacija, suteikusi šiems vabzdžiams daug privalumų. Iki šiol molekulinių tyrimų su šiais drugiais atlikta ypač mažai, todėl visi publikuoti apžvalginiai darbai (tiek Lietuvos autorių, tiek užsienio mokslininkų), iki... [toliau žr. visą tekstą] / The field of molecular biology has expanded greatly in the last ten years and currently many entomologists want to use this technology since it is a new level of carrying out studies of insect ecological systems and taxonomy. The study of mitochondrial DNA (mtDNA) sequences has become the method for a wide range of taxonomic, population and evolutionary investigations in Lepidoptera (Lunt et al, 1996). The increasing popularity of molecular taxonomy will undoubtedly exert a major impact on conservation biology practice. The benefit of such approaches is undeniable since they will clearly be an asset to rapid biological assessments of poorly known taxa or unexplored areas, and to the discovery of cryptic biodiversity. The Tischeriidae and Elachistidae represent rather small families as compared to many other groups of Lepidoptera. Moths are with wingspan from 6–13 mm. They are found all over the world, but most species are known from Boreal, Palearctic and Neotropical regions. These moths are leaf-miners during all larval instars. Molecular tools can help to identify this group. A lot of Tischeriidae and Elachistidae species are siblings externally, and their identification is very problematic, so in this case the structure of the male genital is more popular. However, only two articles dealt with the results of the mitochondrial DNA analysis in Elachista species from Australia (Kaila and Ståhls, 2006) and Tisheria ptarmica from the United Arab Emirates (Nieukerken, 2010)... [to full text]
6

Connectivity within a metapopulation of the foundation species, Ridgeia piscesae Jones (Annelida, Siboglinidae), from the Endeavour Hydrothermal Vents Marine Protected Area on the Juan de Fuca Ridge

Puetz, Lara 30 April 2014 (has links)
The natural instability of hydrothermal vents creates variable environmental conditions among habitat patches. Habitat differences correspond to phenotypic variation in Ridgeia piscesae, the only ‘vent tubeworm’ on the spreading ridges of the Northeast Pacific. Ridgeia piscesae that occupy high fluid flux habitats have rapid growth rates and high reproductive output compared to tubeworms in habitats with low rates of venting fluid delivery. As recruitment occurs in all settings, worms in the “optimal habitat” may act as source populations for all habitat types. Ridgeia piscesae is a foundation species in the Endeavour Hydrothermal Vents Marine Protected Area of the Juan de Fuca Ridge. The objective of this thesis was to assess fine scale population structure in Ridgeia piscesae within the Endeavour vent system using genetic data. Population structure was assessed by analysis of the mitochondrial COI gene in 498 individuals collected from three vent sites of the Juan de Fuca Ridge; Middle Valley (n=26), Endeavour Segment (n=444) and Axial Volcano (n=28). Genotyping using microsatellite markers was attempted but all loci developed for closely related tubeworm species failed to amplify microsatellites in Ridgeia piscesae. Sequence analysis identified 32 mitochondrial COI haplotypes; one dominant haplotype (68%), three common haplotypes (4%-7%) and the remainder were rare (<2%). Axial Volcano was differentiated from Middle Valley and Endeavour. Within Endeavour, genetic sub-structuring of Ridgeia piscesae occurred among vent fields (Clam Bed, Main Endeavour and Mothra) and habitat types < 10 km apart. Patterns of genetic variation and coalescent based models suggested that gene flow among vent fields moved in a north to south direction in individuals from high flux habitat but from south to north in individuals from low flux habitat. Tubeworms from low flux habitat had more nucleotide polymorphisms and haplotypes than those from high flux habitats. Estimates of the number of immigrants per generation moving from high flux to low flux subpopulations was four times higher than in the reverse direction. The effective population size was estimated to be three times greater in high flux habitat when the generation times for individuals from each habitat type were considered. Demographic tests for population equilibrium identified a recent and rapidly expanding metapopulation at Endeavour. Models of gene flow in Ridgeia piscesae reflected the general oceanographic circulation described at Endeavour. Genetic data illustrate that dispersing larvae exploit the bi-directional currents created through plume driven circulation within the Endeavour axial valley and suggest that adult position on or near chimneys may influence larval dispersal trajectories upon release. Building on known ecological and biological features, this study also showed that Ridgeia piscesae from limited and ephemeral high flux habitat act as sources to the overall metapopulation and that asymmetrical migration and habitat stability sustain high genetic diversity in low flux sinks. The overall metapopulation at Endeavour experiences frequent extinction and recolonization events, differences in individual reproductive success, and source-sink dynamics that decrease the overall effective size and genetic diversity within the population. These factors have important implications for the conservation of a foundation species. / Graduate / 0307 / 0329 / 0369 / lcpuetz@uvic.ca
7

Análise dos genes mitocondriais COI e 16S de populações de Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae) de diferentes localidades geográficas

Baggio, Mariah Valente [UNESP] 24 February 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-24Bitstream added on 2014-06-13T18:26:17Z : No. of bitstreams: 1 baggio_mv_me_jabo.pdf: 512063 bytes, checksum: 11244a431e6c0f8cc5195b1c7d20e1bd (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Chrysoperla externa é uma espécie de crisopídeo encontrada em diversos agroecossistemas brasileiros, capaz de se alimentar de diferentes pragas agrícolas. Em cada ambiente em que for encontrada poderá sofrer diferentes pressões seletivas do ambiente. Para a verificação das mutações genéticas presentes nas populações de C. externa podem ser usados marcadores moleculares, em especial os genes mitocondriais, que são de fácil manipulação. C. externa é de fácil criação e a mais estudada para multiplicação massal, por isso se faz necessário estudar a resposta das populações quando liberadas em ambientes diferentes, visto que estas podem não sobreviver em áreas biogeográficas distintas, inviabilizando o seu papel como agente de controle de pragas. O objetivo deste trabalho foi caracterizar geneticamente as populações de C. externa nos municípios de Brotas (SP), Jaboticabal (SP), Rifaina (SP), São Carlos (SP), São José dos Campos (SP) e São Sebastião do Paraíso (MG). Para o gene COI foram verificados oito haplótipos, seis mutações e a maior diversidade haplotípica foi encontrada em Brotas e São Sebastião do Paraíso. Para o gene 16S foram observadas quatro mutações, seis haplótipos e a maior diversidade haplotípica ocorreu no município de São Sebastião do Paraíso. A distância genética encontrada entre as populações de C. externa não foi significativa para os dois genes analisados, evidenciando que provavelmente as populações são geneticamente compatíveis. O estudo da estrutura genética dessas populações de C. externa, de ambos os genes, mostrou que essas populações não apresentam um padrão de distribuição haplotípica. Então, talvez sejam necessários outros estudos com populações desta espécie oriundas de localidades mais distantes geograficamente dos que as utilizadas neste trabalho / Chrysoperla externa is a species of green lacewing found in several Brazilian agroecosystems able to feed on various agricultural pests. In each environment that is found may experience different environmental selective pressures. In order to verify genetic mutations in C. externa populations it may be used molecular markers, in particular mitochondrial genes, which are easy handling and extraction. C. externa is easy to create and the most studied for mass multiplication, so it is necessary to study on the response of populations when released in different environments, since they may not survive in different biogeographic areas, derailing its role as a pest controller. The objective of this study was to characterize genetically the populations of C. externa from the cities of Brotas (SP), Jaboticabal (SP), Rifaina (SP), São Carlos (SP), São José dos Campos (SP) and São Sebastião do Paraíso (MG). For the COI gene it was found eight haplotypes, six mutations and greater haplotype diversity in Brotas and São Sebastião do Paraíso. In the 16S there were four mutations, six haplotypes and haplotype diversity was higher in São Sebastião do Paraíso. The genetic distance among populations of C. externa was not significant for the two genes analyzed, showing that the populations are probably genetically compatible. The study of the genetic structure of populations of C. externa, showed for both genes that these populations do not show a pattern of haplotype distribution. So, it may need further study on populations of this species originating from geographically more distant locations of those used in this work
8

Análise dos genes mitocondriais COI e 16S de populações de Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae) de diferentes localidades geográficas /

Baggio, Mariah Valente. January 2010 (has links)
Orientador: Sérgio de Freitas / Banca: Nilza Maria Martinelli / Banca: Karina Lucas da Silva Brandão / Resumo: Chrysoperla externa é uma espécie de crisopídeo encontrada em diversos agroecossistemas brasileiros, capaz de se alimentar de diferentes pragas agrícolas. Em cada ambiente em que for encontrada poderá sofrer diferentes pressões seletivas do ambiente. Para a verificação das mutações genéticas presentes nas populações de C. externa podem ser usados marcadores moleculares, em especial os genes mitocondriais, que são de fácil manipulação. C. externa é de fácil criação e a mais estudada para multiplicação massal, por isso se faz necessário estudar a resposta das populações quando liberadas em ambientes diferentes, visto que estas podem não sobreviver em áreas biogeográficas distintas, inviabilizando o seu papel como agente de controle de pragas. O objetivo deste trabalho foi caracterizar geneticamente as populações de C. externa nos municípios de Brotas (SP), Jaboticabal (SP), Rifaina (SP), São Carlos (SP), São José dos Campos (SP) e São Sebastião do Paraíso (MG). Para o gene COI foram verificados oito haplótipos, seis mutações e a maior diversidade haplotípica foi encontrada em Brotas e São Sebastião do Paraíso. Para o gene 16S foram observadas quatro mutações, seis haplótipos e a maior diversidade haplotípica ocorreu no município de São Sebastião do Paraíso. A distância genética encontrada entre as populações de C. externa não foi significativa para os dois genes analisados, evidenciando que provavelmente as populações são geneticamente compatíveis. O estudo da estrutura genética dessas populações de C. externa, de ambos os genes, mostrou que essas populações não apresentam um padrão de distribuição haplotípica. Então, talvez sejam necessários outros estudos com populações desta espécie oriundas de localidades mais distantes geograficamente dos que as utilizadas neste trabalho / Abstract: Chrysoperla externa is a species of green lacewing found in several Brazilian agroecosystems able to feed on various agricultural pests. In each environment that is found may experience different environmental selective pressures. In order to verify genetic mutations in C. externa populations it may be used molecular markers, in particular mitochondrial genes, which are easy handling and extraction. C. externa is easy to create and the most studied for mass multiplication, so it is necessary to study on the response of populations when released in different environments, since they may not survive in different biogeographic areas, derailing its role as a pest controller. The objective of this study was to characterize genetically the populations of C. externa from the cities of Brotas (SP), Jaboticabal (SP), Rifaina (SP), São Carlos (SP), São José dos Campos (SP) and São Sebastião do Paraíso (MG). For the COI gene it was found eight haplotypes, six mutations and greater haplotype diversity in Brotas and São Sebastião do Paraíso. In the 16S there were four mutations, six haplotypes and haplotype diversity was higher in São Sebastião do Paraíso. The genetic distance among populations of C. externa was not significant for the two genes analyzed, showing that the populations are probably genetically compatible. The study of the genetic structure of populations of C. externa, showed for both genes that these populations do not show a pattern of haplotype distribution. So, it may need further study on populations of this species originating from geographically more distant locations of those used in this work / Mestre
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História Demográfica e Estrutura de Populações para a Espécie Cactófila Drosophila meridionalis. / Demographic History and Population Structure for the Cactophilic Species Drosophila meridionalis.

Dora Yovana Barrios Leal 01 March 2013 (has links)
Drosophila meridionalis é uma espécie endêmica da América do Sul, sendo amplamente distribuída na Costa Atlântica do Brasil. Com o objetivo de elaborar uma hipótese filogeográfica para esta espécie foram obtidas sequências do gene nuclear period e do gene mitocondrial COI. Foram calculados os índices de diversidade nucleotídica e realizados os testes: AMOVA, testes de neutralidade, a Mismatch Distribution, Bayesian Skyline Plot, NCPA. Foram obtidas três redes pelo gene COI, denominadas A (populações do interior), B (populações do litoral sul) e C (populações do litoral sudeste e oriental) e uma única rede obtida para o gene period, esta rede divide as populações em dois grupos sendo o primeiro congruente com a rede A e o segundo compreendendo as redes B e C, do gene COI. A AMOVA mostrou uma estruturação alta e significativa entre as populações do interior e o litoral para os dois genes (ct=0,72 gene COI; ct=0,70 gene period), que pode ser explicada pela presença de barreiras geográficas, como a Serra do Mar. Eventos de expansão populacional e de fluxo gênico restrito com isolamento por distância foram detectados nas populações do litoral e o interior respectivamente. A expansão da área de ocorrência de D. meridionalis provavelmente teve inicio com as populações do litoral do Rio Grande de Sul, em direção ao litoral de Santa Catarina com posterior colonização a longa distância dos estados de São Paulo, Rio de Janeiro e Bahia. Migrações assincrônicas de indivíduos de populações litorâneas de São Paulo e Santa Catarina provavelmente colonizaram o interior de São Paulo, e a partir destas populações, se iniciara uma expansão populacional em direção ao sul pelo interior, colonizando o Paraná e Rio Grande do Sul. A análise bayesiana (MCCT) indicou que o tempo do ancestral comum mais recente (TMRCA) para todos os haplótipos de D. meridionalis é de 81.700 anos atrás, data que marca a separação das populações do interior e do litoral aproximadamente no final do Pleistoceno. Eventos similares têm sido sugeridos para explicar a distribuição geográfica de espécies do cluster D. buzzatii, que ocorrem em simpatria em grande parte com populações de D. meridionalis. Esta espécie, como as espécies do cluster D. buzzatii, apresentou indicativos de flutuações demográficas, podendo estar associadas à expansão e contração da distribuição da vegetação xerofítica, durante as oscilações paleoclimáticas do Pleistoceno. / Drosophila meridionalis is an endemic species of South America, being widely distributed in the Atlantic Coast of Brazil. Aiming to develop a phylogeographic hypothesis for this species, sequences of mitochondrial COI and nuclear period genes were obtained. The diversity indexes, AMOVA, neutrality tests, Mismatch Distribution, Bayesan Skyline Plot and NCPA were calculated. We obtained three networks for the COI gene, denominated A (inland populations), B (south coast populations) and C (eastern and southeastern coast populations) and a single network obtained for the period gene, this network divides the population into two groups, being the first congruent with the network A of the COI gene and the second comprising the networks B and C of the COI gene. The AMOVA results, showed a high and significant structuring among inland and coastal populations, for both genes (ct=0,72 COI gene; ct=0,70 period gene), that can be explained by the presence of geographical barriers, such as Serra do Mar. Population expansion events and restricted gene flow with isolation by distance events were detected in coastal and inland populations respectively. The expansion of the area of occurrence of D. meridionalis probably was initiated with the populations of the coast of Rio Grande do Sul, towards the coast of Santa Catarina with subsequent long-distance colonization of the states of São Paulo, Rio de Janeiro and Bahia. Asynchronic migrations of individuals from coastal populations of São Paulo and Santa Catarina probably colonized the inland of São Paulo, and from these populations, a population expansion towards the south through the inland was initiated, colonizing the states of Paraná and Rio Grande do Sul. The bayesian analysis (MCCT) indicated that the time of the most recent common ancestor (TMRCA) for all haplotypes of D. meridionalis is from 81,700 years ago, a date that marks the separation of inland and coastal populations approximately at the end of the Pleistocene. Similar events have been suggested to explain the geographic distribution of species of the cluster D. buzzatii, occurring in sympatry largely with populations of D. meridionalis. This species, as the cluster D. buzzatii species, presented indicatives of demographic fluctuations, which can be associated with the expansion and contraction of the distribution of xerophytic vegetation, during the paleoclimatic fluctuations of the Pleistocene.
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As Rotas de Dispersão de Drosophila buzzatii na América do Sul / The Dispersion Routes of Drosophila buzzatii in South America

Santos, Mateus Henrique 01 April 2011 (has links)
Drosophila buzzatii é uma espécie cactófila associada a diferentes espécies de cactos e distribuída nos diferentes Domínios fitogeográficos da América do Sul. Baseado na diversidade de inversões cromossômicas e densidade populacional, o Chaco foi considerado por alguns autores como o centro de origem da espécie. Entretanto, trabalhos recentes, utilizando aloenzimas e DNA mitocondrial, apontaram para uma possível origem na Caatinga. Os objetivos deste trabalho foram delinear rotas de dispersão da espécie para explicar sua distribuição atual e possível distribuição durante o último período glacial, na América do Sul. Foram obtidas seqüências de 714 pb da COI do mtDNA de 132 indivíduos em 44 localidades, gerando 36 haplótipos. Foram calculados os índices de diversidade nucleotídica, o teste AMOVA, testes de neutralidade, a Mismatch Distribution, Baesyan Skyline Plot, NCPA e o sentido dos movimentos migratórios (Migrate N) a fim de determinar parte da história evolutiva da espécie. As diversidades nucleotídicas encontradas por Domínio foram de 0,0030 Caatinga; 0,0019 - Mata Atlântica; 0,0020 Cerrado; 0,0011 - Pampas e 0,0004 - Chaco. A AMOVA mostrou que 68,33% da variação é intra-populacional e que uma porção significativa da variação é devido a diferenças inter-regionais (ct = 0,07124 p = 0,00196). Os testes de Neutralidade (D de Tajima = -2,4150, p = 0,0317 e Fs de Fu = -28,6719, p = 0,00001), a forma em estrela da rede e haplótipos, e a Mismatch Distribution confirmam um evento de expansão populacional estimado em aproximadamente 494.257,3 anos atrás, segundo modelo de Rogers e Harpending (1992). Entretanto, a Baesyan Skiline Plot demonstrou que esse movimento de expansão parece ser mais antigo, cerca de 550.000 650.000 anos atrás. A NCPA demonstrou que há fluxo gênico restrito com isolamento por distância, confirmado pelo teste de Mantel e alguma dispersão a longa distância em alguns dos clados analisados. O resultado do programa Migrate N indicou um padrão complexo migratório entre os domínios, porém um padrão norte/sul pôde ser verificado. A estruturação genética pode ser explicada devido à grande área de distribuição da espécie, gerando isolamento por distância e pela presença de barreiras geográficas e climáticas (entre o Cerrado e a Caatinga) e no estado do Rio de Janeiro e Espírito Santo (ao longo da Mata Atlântica) onde há pouco ou nenhum indivíduo da espécie. Os eventos de expansão ocorreram no Quaternário durante o período glacial conhecido como Ilinioian e suas subdivisões. A partir dos resultados deste trabalho foi possível traçar diversas rotas de migração possíveis entre os domínios utilizados, sendo que o movimento mais antigo partiu da Caatinga o que vai contra a hipótese de que o Centro de Origem seja o Chaco. / The fruit-fly Drosophila buzzatii is a cactophilic species in association with cactus species distributed along the Phytogeographic Domains of Caatinga, Cerrado, Atlantic Forest, Pampas and Chaco. Based in the diversity of chromosomal inversion and populational density of the species, the Chaco Domain was considered the Center of Origin of the D. buzzatii. However, recent works, using allozymes and DNAmt, showed a possible origin of the D. buzzatii in the Caatinga. The objectives of this work were trace historical dispersion routes of D. buzzatii, current and ancient areas of distribution in the South America. We obtained DNA sequences in 132 samples in 44 localities with 714 bp length from the COI mtDNA gene, generating 36 haplotypes. The diversity indexes, AMOVA, neutrality tests, Mismatch Distribution, Baesyan Skyline Plot, NCPA and sense of migration movements was calculated, to describe part of the evolutionary history of the species. The nucleotide diversity was 0,0030 - Caatinga, 0,0019 - Mata Atlântica, 0,0020 - Cerrado, 0,0011 - Pampas and 0,0004 - Chaco. The AMOVA results, grouped by Domain showed that 68,33% of the variation is intra-population and a significant portion of the variation is due to inter-regional differences (ct = 0,07124 p = 0,00196). The Neutrality tests (Tajimas D = -2,4150, p = 0,0317 and Fus Fs = -28,6719, p = 0,00001), the star-shape of the haplotype network, and Mismatch Distribution showed population expansion signs, estimated in 494.257,3 ybp, according Rogers and Harpending model (1992). However, the BSP showed that the movement is ancient, estimated in 550.000 650.000 ybp. The NCPA showed restricted gene flow with isolation by distance, confirmed by the Mantel Test and some long distance dispersion. The results of the program Migrate N showed a complex pattern of migration between the domains, but a north/south pattern could be identified. The genetic structure can be explained to the widespread distribution of the species, that could generate isolation by distance and by the presence of geographic and climatic barriers (between Cerrado and Caatinga domains) and in the States of Rio de Janeiro and Espírito Santo (along the Atlantic Forest) when there is none or few individuals of the species D. buzzatii. The expansion movements occurred in the Quaternary Period during glaciations events in the Illinoian and their subdivisions, due to the decrease of the global moisture that generated favorable conditions to the expansion of the dry vegetation and associated species. Based on the results of this work it was possible to delineate many migration routes between the phytogeographic domains, and the more ancient movement started in the Caatinga and this result not support the hypothesis that Chaco was the Center of Origin from D. buzzatii.

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