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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.
81

Population genetic analyses in the orchid genus <i>Gymnadenia</i> : a conservation genetic perspective

Gustafsson, Susanne January 2003 (has links)
<p>Small populations are facing a particular risk of extinction due to a lack of appropriate genetic diversity and associated negative effects, factors dealt with in the discipline of conservation genetics. Many orchid species exhibit characteristics that make them a perfect study object in the scope of conservation genetics. The aim with this thesis was to investigate genetic structure at different levels in two orchid species <i>Gymnadenia conopsea</i>, geographically widespread, although diminishing and <i>G. odoratissima</i> with a long history of being rare. Microsatellite markers, developed in and used in studies of <i>G. conopsea</i> were also used in the study of <i>G. odoratissima</i>.</p><p>Populations of <i>G. conopsea</i> expressed high levels of genetic variation and a certain amount of gene flow, although investigated mating pattern in a small population indicated non-random mating among individuals, with the majority of pollen exchange between near neighbours, and noticeable levels of geitonogamous pollinations. Further a pronounced year to year variation in flowering frequency among individuals was found. </p><p>It was also discovered that flowering time variants (early and late) within the species <i>G. conopsea</i> were highly differentiated and seem to have had a more ancient historical separation than the separation between the two different species, <i>G. conopsea</i> and <i>G. odoratissima. </i></p><p>Levels of genetic variation in the rare congener, <i>G. odoratissima</i> differed between island and mainland populations where the more numerous island populations expressed larger levels of genetic variation and were less differentiated compared to the few remaining and genetically depauperated mainland populations.</p><p>Uppsala University Library, Box 510, 75120, Uppsala, Sweden </p>
82

Population genetic analyses in the orchid genus Gymnadenia : a conservation genetic perspective

Gustafsson, Susanne January 2003 (has links)
Small populations are facing a particular risk of extinction due to a lack of appropriate genetic diversity and associated negative effects, factors dealt with in the discipline of conservation genetics. Many orchid species exhibit characteristics that make them a perfect study object in the scope of conservation genetics. The aim with this thesis was to investigate genetic structure at different levels in two orchid species Gymnadenia conopsea, geographically widespread, although diminishing and G. odoratissima with a long history of being rare. Microsatellite markers, developed in and used in studies of G. conopsea were also used in the study of G. odoratissima. Populations of G. conopsea expressed high levels of genetic variation and a certain amount of gene flow, although investigated mating pattern in a small population indicated non-random mating among individuals, with the majority of pollen exchange between near neighbours, and noticeable levels of geitonogamous pollinations. Further a pronounced year to year variation in flowering frequency among individuals was found. It was also discovered that flowering time variants (early and late) within the species G. conopsea were highly differentiated and seem to have had a more ancient historical separation than the separation between the two different species, G. conopsea and G. odoratissima. Levels of genetic variation in the rare congener, G. odoratissima differed between island and mainland populations where the more numerous island populations expressed larger levels of genetic variation and were less differentiated compared to the few remaining and genetically depauperated mainland populations. Uppsala University Library, Box 510, 75120, Uppsala, Sweden
83

Effects of Agriculture on Abundance, Genetic Diversity and Fitness in the Common Frog, Rana temporaria

Johansson, Markus January 2004 (has links)
The aims of this thesis were to evaluate the effects of agriculture on amphibians in terms of (i) population genetic consequences of agriculture-induced spatial changes of the landscape and (ii) local adaptation and tolerance to frequently used agrochemicals. The study was performed using the common frog Rana temporaria as a model. Abundance, occurrence, genetic diversity and gene flow were negatively affected by agriculture in southern Sweden, but unaffected or even positively affected by agriculture in the central and northern regions, respectively. These test parameters correlated positively with landscape diversity both in the south and in the north. Moreover, the size and occurrence of R. temporaria populations decreased towards the north i.e. the margin of the species’ distribution range. In accordance with theoretical expectations, genetic variability decreased and population substructuring increased as a negative function of (effective) population size. Southern Swedish common frogs are naturally exposed to higher levels of nitrates, and thus have a higher tolerance to high nitrate levels than their northern conspecifics. This suggests local adaptation to naturally varying nitrate levels. Consequently, increased anthropogenic supplementation of nitrate could impact more the northern than the southern Swedish common frog populations. Exposure to the pesticides azoxystrobin, cyanazine and permethrin at ecologically relevant concentrations had small or no effects on R. temporaria tadpoles. The populations with lowest microsatellite variation (fragmented populations) in southern Sweden had considerably lower fitness in terms of survival and growth as compared to those with the highest genetic variability (non-fragmented populations). The results indicate that populations with low levels of neutral genetic variability were phenotypically less differentiated than populations with higher levels of variability. One possible explanation for this is that the degree of population differentiation in low variability populations has been constrained due to lack of suitable genetic variation or inefficiency of selection relative to genetic drift.
84

Investigation into population genetic structure of eel Anguilla anguilla (L.) and perch Perca fluviatilis L. within the context of anthropogenic activity / Ungurio Anguilla anguilla (L.) ir ešerio Perca fluviatilis L. populiacinės-genetinės struktūros tyrimai antropogeninio poveikio kontekste

Ragauskas, Adomas 25 June 2013 (has links)
Seeking for a sustainable exploitation of the populations of commercialy valuable fish species without causing danger to their genetic resources it is necessary to amass extensive data about the population genetic structure of this fish species. When preparing the thesis a total of 221 eels and 262 perch were analysed. Fish samples collected in Lithuania and Latvia were studied using microsatellite DNA, the mtDNA D-loop region and mtDNA cyt b markers. Original primer pairs Ang1 and Ang2 have been designed for the mtDNA analysis of the eel. On the basis of the Anguilla genus species mtDNA D-loop region data obtained during work it can be stated that inland and territorial water bodies of Lithuania contain no A. japonica and A. rostrata species. The molecular investigations carried out indicate that the population genetic structure of the European eel is characterized by the genetic mosaic, which is formed due to the existence of reproductively isolated groups. Statistically significant genetic differentiation between the eel groups naturally recruited to Lithuania and Latvia and introduced to Lithuanian lakes has not been determined (p > 0.05). However, the eels stocked into different lakes of Lithuania differ in their genetic diversity. Pairwise comparisons of the Lithuanian and Latvian perch populations based on the mtDNA D-loop region data revealed that the perch population of Lake Drūkšiai was statistically significantly (p < 0.05) different from all other perch... [to full text] / Siekiant tvariai eksploatuoti verslinių žuvų populiacijas nesukeliant pavojaus jų genetiniams resursams būtina sukaupti daug duomenų apie šių rūšių populiacinę-genetinę struktūrą. Iš viso tyrimams panaudoti 221 unguriai ir 262 ešeriai. Lietuvoje ir Latvijoje surinkti žuvų audinių pavyzdžiai tirti naudojant mikrosatelitinės DNR, mtDNR D-kilpos regiono ir mtDNR cyt b žymenis. Ungurių mtDNR analizei sukurtos originalios Ang1 ir Ang2 pradmenų poros. Remiantis disertacinio darbo metu atliktais Anguilla genties rūšių mtDNR D-kilpos regiono tyrimais, galima teigti, jog šiuo metu A. japonica ir A. rostrata rūšių, tiek tirtuose Lietuvos vidaus vandens telkiniuose, tiek Lietuvos teritoriniuose vandenyse nėra. Atlikti molekuliniai tyrimai rodo, kad europinio upinio ungurio populiacinė-genetinė struktūra pasižymi genetine mozaika, kurios susiformavimą lemia reproduktyviai izoliuotos grupės. Tarp natūraliai į Lietuvą ir Latviją atplaukusių ir introdukuotų Lietuvos ežeruose ungurių grupių statistiškai patikima genetinė diferenciacija nenustatyta (p > 0,05), tačiau skirtinguose Lietuvos ežeruose gyvenantys unguriai pasižymi skirtinga genetine įvairove. Atliktų Perca fluviatilis mtDNR D-kilpos regiono tyrimų rezultatai rodo, jog Drūkšių ežero ešerių populiacija statistiškai patikimai (p < 0,05) skiriasi nuo visų kitų Lietuvos ir Latvijos ešerių populiacijų. Nustatyta, kad nuo Lietuvos pietvakarinės dalies iki Latvijos centrinės dalies plyti kelių skirtingų ešerių genetinių linijų kontaktinė... [toliau žr. visą tekstą]
85

Ungurio Anguilla anguilla (L.) ir ešerio Perca fluviatilis L. populiacinės-genetinės struktūros tyrimai antropogeninio poveikio kontekste / Investigation into population genetic structure of eel Anguilla anguilla (L.) and perch Perca fluviatilis L. within the context of anthropogenic activity

Ragauskas, Adomas 25 June 2013 (has links)
Siekiant tvariai eksploatuoti verslinių žuvų populiacijas nesukeliant pavojaus jų genetiniams resursams būtina sukaupti daug duomenų apie šių rūšių populiacinę-genetinę struktūrą. Iš viso tyrimams panaudoti 221 unguriai ir 262 ešeriai. Lietuvoje ir Latvijoje surinkti žuvų audinių pavyzdžiai tirti naudojant mikrosatelitinės DNR, mtDNR D-kilpos regiono ir mtDNR cyt b žymenis. Ungurių mtDNR analizei sukurtos originalios Ang1 ir Ang2 pradmenų poros. Remiantis disertacinio darbo metu atliktais Anguilla genties rūšių mtDNR D-kilpos regiono tyrimais, galima teigti, jog šiuo metu A. japonica ir A. rostrata rūšių, tiek tirtuose Lietuvos vidaus vandens telkiniuose, tiek Lietuvos teritoriniuose vandenyse nėra. Atlikti molekuliniai tyrimai rodo, kad europinio upinio ungurio populiacinė-genetinė struktūra pasižymi genetine mozaika, kurios susiformavimą lemia reproduktyviai izoliuotos grupės. Tarp natūraliai į Lietuvą ir Latviją atplaukusių ir introdukuotų Lietuvos ežeruose ungurių grupių statistiškai patikima genetinė diferenciacija nenustatyta (p > 0,05), tačiau skirtinguose Lietuvos ežeruose gyvenantys unguriai pasižymi skirtinga genetine įvairove. Atliktų Perca fluviatilis mtDNR D-kilpos regiono tyrimų rezultatai rodo, jog Drūkšių ežero ešerių populiacija statistiškai patikimai (p < 0,05) skiriasi nuo visų kitų Lietuvos ir Latvijos ešerių populiacijų. Nustatyta, kad nuo Lietuvos pietvakarinės dalies iki Latvijos centrinės dalies plyti kelių skirtingų ešerių genetinių linijų kontaktinė... [toliau žr. visą tekstą] / Seeking for a sustainable exploitation of the populations of commercialy valuable fish species without causing danger to their genetic resources it is necessary to amass extensive data about the population genetic structure of this fish species. When preparing the thesis a total of 221 eels and 262 perch were analysed. Fish samples collected in Lithuania and Latvia were studied using microsatellite DNA, the mtDNA D-loop region and mtDNA cyt b markers. Original primer pairs Ang1 and Ang2 have been designed for the mtDNA analysis of the eel. On the basis of the Anguilla genus species mtDNA D-loop region data obtained during work it can be stated that inland and territorial water bodies of Lithuania contain no A. japonica and A. rostrata species. The molecular investigations carried out indicate that the population genetic structure of the European eel is characterized by the genetic mosaic, which is formed due to the existence of reproductively isolated groups. Statistically significant genetic differentiation between the eel groups naturally recruited to Lithuania and Latvia and introduced to Lithuanian lakes has not been determined (p > 0.05). However, the eels stocked into different lakes of Lithuania differ in their genetic diversity. Pairwise comparisons of the Lithuanian and Latvian perch populations based on the mtDNA D-loop region data revealed that the perch population of Lake Drūkšiai was statistically significantly (p < 0.05) different from all other perch... [to full text]
86

The Impact of Migration on the Evolution and Conservation of an Endemic North American Passerine: Loggerhead Shrike (Lanius ludovicianus)

CHABOT, AMY A 26 January 2011 (has links)
Migration acts as a selective force on the ecology and evolutionary trajectory of species, as well as presenting fundamental challenges for conservation. My thesis examines the impact of migration by exploring patterns of differentiation among and within migratory and non-migratory populations of the Loggerhead Shrike (Lanius ludovicianus). First, I use morphological, genotypic, stable isotope and leg band recovery data to quantify migratory connectivity in the species. Comparison across markers reveals a generally concordant pattern of moderate connectivity to the Gulf Coast, but overall mixing among populations on the wintering grounds. Combining data from multiple markers in a Bayesian framework improves the resolution of assignment of wintering birds to a breeding ground origin. Information on the species’ migratory patterns provides an explicit framework for interpreting patterns of genetic and ecological variation. I test two hypotheses regarding the interaction of gene flow and migratory habit: (1) migration facilitates gene flow; and (2) gene flow will occur most often along the axis of migration. Genetic population structure in migratory populations is weaker than in non-migratory populations, with gene flow facilitated by dispersal movements of females and first year breeders. As predicted, gene flow occurs most often along the north-south axis of migration, likely due either to opportunistic settling of dispersers or potentially, pairing on the wintering grounds. I investigate variation in the extent and scheduling of moult in relation to underlying genetic differences among populations, age, sex, body size, food availability and migratory habit. I find a pattern of interrupted moult across migratory populations, which may represent a trade-off between time allocated to breeding versus molt and migration. Loggerhead Shrikes in eastern and more southerly migratory populations undergo a greater extent of their moult on the breeding grounds and non-migratory individuals undergo a more extensive pre-formative moult than migratory individuals. I interpret this as suggesting a trade-off between resources allocated to molt versus those required for reproduction. / Thesis (Ph.D, Biology) -- Queen's University, 2011-01-25 15:54:36.593
87

Evidências do efeito da fragmentação da mata atlântica na variabilidade e estruturação genética de Chiroxiphia caudata

Niero, Leonardo Paes 20 October 2014 (has links)
Made available in DSpace on 2016-06-02T19:32:13Z (GMT). No. of bitstreams: 1 6436.pdf: 1547654 bytes, checksum: 6f984d349332adbb8920bb20ab338180 (MD5) Previous issue date: 2014-10-20 / Universidade Federal de Sao Carlos / Habitat fragmentation is one of the main threats to biodiversity and one of the main challenges faced by conservation biology. This study assessed the habitat fragmentation effects on the genetic variability of Chiroxiphia caudata, which is an Atlantic Forest endemic bird species. Nine microsatellite loci were used for the analysis of individuals from five Atlantic Forest areas. We found departure from HWE is due to heterozygotes deficit and positive values for the inbreeding coefficient (Fis) for all populations. Private alleles were found in all areas. Fst, Dest, Bayesian and factorial correspondence analyses indicated that populations are genetically structured, but the distance could not explain the differentiation between areas. Apparently, this species did not suffered from a reduction in its variability because of the habitat fragmentation process. The fragmentation and its consequences as the reduction of gene flow may be acting in order to increase the differentiation between areas, including nearby areas that already show evidence of early differentiation.The choice of C. caudata for this study concerning the Atlantic Forest revealed the most fragmented areas played an important role for the specie by sheltering great genetic diversity within itself. Although not considered a very specialized specie as to their habits, the study model based on C. caudata showed that even more generalist species may be affected by fragmentation. When dealing with more specialized species, this scenario can become even worse. / A fragmentação de habitats é uma das principais ameaças à biodiversidade e um dos principais desafios enfrentados pela biologia da conservação. Este estudo avaliou os efeitos da fragmentação de habitat sobre a variabilidade genética de Chiroxiphia caudata, uma espécie endêmica da Mata Atlântica. Foram utilizados 9 loci de microssatélites para a análise de 78 indivíduos inseridos em cinco áreas de Mata Atlântica. Encontramos desvios no equilíbrio de Hardy-Weinberg para déficit de heterozigotos e valores positivos de FIS em todas as populações. Foram encontrados alelos privados em todas as áreas. Quanto a estruturação populacional, as análises de Fst, Dest, análise Bayesiana e análise de correspondência fatorial indicam que as populações são estruturadas geneticamente e que somente a distância não pode explicar a diferenciação entre as áreas. Aparentemente esta espécie não teve sua variabilidade reduzida a partir do processo de fragmentação. A fragmentação e suas consequências quanto a diminuição do fluxo gênico pode estar atuando de maneira a aumentar a diferenciação entre áreas, inclusive áreas próximas que já apresentam indícios de início de diferenciação. A utilização de C. caudata como modelo de estudo da Mata Atlântica mostra que áreas mais fragmentadas possuem um papel muito importante para espécie, abrigando grande diversidade genética. Mesmo não sendo considerada uma espécie muito especializada quanto aos seus hábitos, o modelo de estudo baseado em C. caudata mostrou que mesmo espécies mais generalistas podem ser afetadas pela fragmentação. Quando tratamos de espécies mais especializadas, este panorama pode se tornar ainda pior.
88

REML/BLUP para predição de valores genotípicos de topcrosses e seleção de testadores em milho / REML/BLUP for the prediction of topcross genotypic values and selection of testers in corn

Silva, Flávia Alves Marques da [UNESP] 18 February 2016 (has links)
Submitted by Flávia Alves Marques da Silva null (flavia_alvesms@hotmail.com) on 2016-04-12T00:49:43Z No. of bitstreams: 1 Dissertação FAMS.pdf: 1151230 bytes, checksum: ca0a6199d3ff01fbcb0f85441e03066b (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-04-13T14:04:07Z (GMT) No. of bitstreams: 1 silva_fam_me_jabo.pdf: 1151230 bytes, checksum: ca0a6199d3ff01fbcb0f85441e03066b (MD5) / Made available in DSpace on 2016-04-13T14:04:07Z (GMT). No. of bitstreams: 1 silva_fam_me_jabo.pdf: 1151230 bytes, checksum: ca0a6199d3ff01fbcb0f85441e03066b (MD5) Previous issue date: 2016-02-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Nos programas de melhoramento de milho, a avaliação das linhagens em cruzamentos é uma etapa de alto custo, sendo que o uso e a escolha dos testadores mais adequados podem reduzir a demanda de recursos. Assim, o objetivo desse trabalho foi utilizar a abordagem REML/BLUP de modelos mistos para predição de valores genotípicos de topcrosses, combinando testadores com estruturas genéticas diversificadas. Foram avaliados 234 topcrosses (39 linhagens x 6 testadores), no ano agrícola 2012/13, no delineamento experimental de blocos ao acaso para o caráter produtividade de grãos de milho (t ha-1), altura de plantas (cm) e acamamento e quebramento de plantas (%). Foram realizadas análises de variância e, com as médias fenotípicas dos topcrosses, obteve-se os valores dos BLUPs considerando diferentes níveis de eliminação de testadores. Para verificar a eficiência dos BLUPs foram estimadas as correlações entre as médias fenotípicas e os valores genotípicos preditos com diferentes números e combinação de testadores, bem como os coeficientes de determinação, a coincidência no ordenamento dos topcrosses para seleção e descarte, com 10 e 20% de intensidade, e classificações dos topcrosses quanto à média fenotípica. O método de REML/BLUP se mostra adequado na predição dos valores genotípicos dos topcrosses nas situações com todos os testadores e com diferentes níveis de eliminação de testadores, com resultados variados em função das diversas combinações obtidas, para todos os caracteres avaliados. É possível estipular um padrão quanto à origem e estrutura genética dos testadores mais recomendados para cada caráter e, considerando todos, é observada uma boa precisão experimental a partir do nível com conjuntos formados por 3 testadores, independente da origem dos constituintes. A predição genotípica, através do REML/BLUP, auxilia na seleção de testadores, sendo que o número de testadores utilizados tem maior influência do que a origem e estrutura dos mesmos. / In maize breeding programs the evaluation of lines at crosses is a costly step, and the use and the choice of the most appropriate testers can reduce the demand for resources. The objective of this work was to use the REML/BLUP approach of mixed models to predict genotypic values of topcrosses using testers with diverse genetic structures. Were evaluated 234 topcrosses (39 lines x 6 testers) in the agricultural year of 2012/13, under the experimental design of randomized blocks for the traits as grain yield (t ha-1 ), plant height (cm) and lodging and breakage of plants (%). Analyses of variance were conducted, and with the phenotypic means of topcrosses were obtained BLUPs values considering different levels of elimination of the testers. In order to check the efficiency of BLUPs, the correlations were estimated between the average phenotypic and the genotypic predicted values with different numbers and combination of the testers, as well as the coefficients of determination, the coincidence in the ranking of topcrosses for selection and discard, with 10 and 20% of intensity, and the classification of the topcrosses as to the phenotypic average. The method of REML/BLUP shown adequate to predict the genotypic values of topcrosses in situations with all testers and with different levels of testers elimination, with varying results depending on the various combinations obtained for all traits. Is possible to set a standard as to the origin and genetic structure of the most recommended testers for each trait, and considering all, a good experimental precision is observed from level with joint formed by three testers, regardless of the origin of the constituents. The genotype prediction, by REML/BLUP, assists in the selection of testers, and the number of testers used has greater influence than the origin and structure of the same.
89

Variabilidade genética e química entre e dentro de populações de Casearia sylvestris Sw. (Salicaceae) no estado de São Paulo

Cavallari, Marcelo Mattos [UNESP] 22 August 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-22Bitstream added on 2014-06-13T19:42:39Z : No. of bitstreams: 1 cavallari_mm_dr_botib.pdf: 2341412 bytes, checksum: 25cb49e35e82d3a208a4d24cb3f50d39 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O presente trabalho teve como objetivo produzir ferramentas e informações úteis para a conservação e exploração racional de Casearia sylvestris Sw. (Salicaceae), uma espécie que produz diterpenos clerodânicos de grande importância farmacológica (casearinas), e que é explorada por extrativismo. Tal objetivo foi alcançado através do desenvolvimento de marcadores microssatélites específicos para C. sylvestris e de um estudo da diversidade genética e química existente entre e dentro de populações do Estado de São Paulo. Tradicionalmente são reconhecidas duas variedades em C. sylvestris (var. sylvestris e var. lingua), o que é motivo de debate devido à existência de formas intermediárias. Este trabalho objetivou, adicionalmente, contribuir com argumentos genéticos para esta discussão. Foi construída uma biblioteca enriquecida em microssatélites, a partir da qual obtiveram-se e validaram-se dez pares de iniciadores (primers) microssatélites específicos para C. sylvestris. Estes pares de iniciadores foram utilizados para o estudo da estrutura genética de populações de C. sylvestris através da amostragem de 376 indivíduos em nove populações distribuídas em quatro ecossistemas (Floresta Ombrófila Densa, Floresta Estacional Semidecidual, Cerrado e ecótonos). As duas variedades foram amostradas de acordo com sua distribuição nestes ecossistemas. A genotipagem dos indivíduos para os locos amostrados foi realizada através de eletroforese em gel de acrilamida lido a 700 e 800 nm por um seqüenciador IR2-DNA Analyser (LI-COR). Os dados foram analisados através de abordagens frequentistas, bayesianas e baseadas na teoria de coalescência, utilizando-se diversos programas computacionais. Para o estudo da diversidade química, as mesmas populações foram amostradas, selecionando-se 12 indivíduos por população, totalizando 108 indivíduos. Adicionalmente, foram... / This work aimed obtaining tools and information for the conservation and rational exploitation of Casearia sylvestris Sw. (Salicaceae), a tree species which produces casearins, pharmacologically important clerodane diterpenes. This goal was achieved through the development of a set of polymorphic microsatellite markers, and through the study of chemical and genetic diversity in populations of C. sylvestris from São Paulo State. Also, we aimed contributing for the debate on the existence of two varieties within this species (var. sylvestris e var. lingua). A genomic library was constructed and 10 primer pairs were obtained. Those primers were utilized for a population genetic structure analysis, in which 376 individuals from nine populations distributed on four different ecosystems (Evergreen Atlantic Forest, Semideciduous Atlantic Forest, Cerrado and ecotones) were sampled. The two varieties were sampled according to its distribution among these populations. Genotyping was performed at 700 and 800 nm by electrophoresis on an IR2-DNA Analyser (LI-COR). The data were analyzed through frequentist, Bayesian and coalescence-based approaches, through the use of several softwares. Chemical diversity was studied by sampling in the same populations (12 individuals per population, i.e. 108 individuals). Also, cuttings of these individuals were prepared, aiming to verify its’ chemical compounds after a year of green-house cultivation. Cuttings’ rooting was problematic and a methodology was developed. Only 46 cuttings survived. Casearins from these 154 individuals (108 + 46) were extracted and analyzed by HPLC. Genetic analysis results suggests a partial genome duplication, as more than two alleles for the same locus were observed in 8% of var. sylvestris individuals and in 70% of var. lingua individuals. Additional studies are necessary to verify the hypothesis of partial genome duplication... (Complete abstract click electronic access below)
90

Colonização e dispersão nos sítios de ocorrência, a genética das populações e história natural de Partamona ailyae Camargo, 1980 (Hymenoptera: Apidae: Meliponini)

Cardoso, Pedro Filipe Menezes 03 June 2016 (has links)
Submitted by Alison Vanceto (alison-vanceto@hotmail.com) on 2017-02-06T11:13:07Z No. of bitstreams: 1 DissPFMC.pdf: 4800471 bytes, checksum: 74835d4fcfc7ca47be3c875080c89712 (MD5) / Approved for entry into archive by Camila Passos (camilapassos@ufscar.br) on 2017-02-08T12:03:44Z (GMT) No. of bitstreams: 1 DissPFMC.pdf: 4800471 bytes, checksum: 74835d4fcfc7ca47be3c875080c89712 (MD5) / Approved for entry into archive by Camila Passos (camilapassos@ufscar.br) on 2017-02-08T12:08:06Z (GMT) No. of bitstreams: 1 DissPFMC.pdf: 4800471 bytes, checksum: 74835d4fcfc7ca47be3c875080c89712 (MD5) / Made available in DSpace on 2017-02-08T12:09:02Z (GMT). No. of bitstreams: 1 DissPFMC.pdf: 4800471 bytes, checksum: 74835d4fcfc7ca47be3c875080c89712 (MD5) Previous issue date: 2016-06-03 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Particular biological features of different bee groups can affect how a certain area will be occupied by them and this can affect directly the genetics of their populations over the long term. In Brazil, there are few studies about gene variation and genetic structure of bee natural populations, as well as on the genetic differentiation levels between eusocial bee populations. The Partamona genus comprises 33 species, distributed from Southern Mexico to Southern Brazil. Partamona ailyae, the model species of this study, occurs in rainforests of Southwestern Amazonia, Central Brazil and xeric regions of Piauí. Its wide distribution, as well as the ability to occupy such heterogeneous environments, piqued our interest to take P. ailyae as a study model. This work aimed to analyze the occupation process at the P. ailyae occurrence sites, population genetics and interpopulational gene flow, and the natural history of this species. Eight expeditions were carried out, and 41 localities of 10 states of Brazil were visited. Among them, active colonies of P. ailyae were found only in 17 localities, being collected specimens of 75 nests. To identify the mitochondrial lineages present in the sampled colonies, five gene regions were used (COI, CytB, 12S, 16S and COI-COII). Estimates of polymorphism levels showed COI and CytB as the most variable regions (11 and seven haplotypes, respectively). For the ribosomal genes, only a few samples were analyzed, because few differences were identified among the sequences. All the 31 samples analyzed for the 12S showed a five bases insertion starting from the position 25 of the sequence, a result not observed in other Partamona species. The most informative genes (COI and CytB) had their sequences concatenated (1114pb). For these regions, 13 haplotypes were observed, two of them were shared and 11 characterized as exclusive of localities. The AMOVA showed that 94.3% of the gene variation is due to interpopulacional differences, revealing a high differentiation among the populations (ΦST = 0.9426; P = 0.000). In addition, one individual from each colony was analyzed for eight heterologous microsatellite loci designed from Melipona bicolor and Partamona helleri. A moderate and statistically significant XIV interpopulational genetic differentiation (ΦST = 0.1491; P = 0.000) was found. The cluster analysis identified four groups by ΔK as the ideal model, and STRUCTURE software showed that all individuals could belong to more than one group, corroborating the “Assignment test”, which indicated that only 50% of the samples were correctly assigned to their original population. Phenotypic segregation analysis was realized in some offsprings, revealing a monoginic/monandric familial structure. From the mitochondrial data, the Mantel test showed a significant correlation between genetic distance and geographic distance (r = 0.2589; P = 0.0231), whereas on basis of the nuclear data, the Mantel test did not indicate significant correlation between genetic distance and geographic distance (r = 0.2090; P = 0.0610). Fu’s Fs and R2 tests did not show significant values. The Bayesian Skyline Plot analysis (BSP) did not show significant fluctuations in the effective size populations of P. ailyae, indicating population stability over time. The values of ΦST estimated for mitochondrial genes and microsatellites were compared, being detected evidence of sex-asymmetric dispersal, in which females are responsible for the areas occupation, and males constitute the disperser sex. In addition, some relevant aspects of the natural history of P. ailyae are shown. / Características inerentes à biologia dos diferentes grupos de abelhas podem afetar como uma determinada área será ocupada e isso pode influenciar diretamente a genética de suas populações no longo prazo. No Brasil, poucos são os estudos que tratam da variabilidade e estrutura genéticas das populações naturais de abelhas, assim como os níveis de diferenciação entre as populações de abelhas eussociais. O gênero Partamona compreende 33 espécies descritas, distribuídas do sul do México ao sul do Brasil. Partamona ailyae ocorre nas matas úmidas do sudoeste da Amazônia, região central do Brasil e regiões xéricas do Piauí. A sua grande distribuição, bem como a capacidade de ocupar ambientes tão heterogêneos, despertou nosso interesse em utilizar P. ailyae como modelo de estudo. O objetivo deste trabalho foi analisar o processo de ocupação nos diversos sítios de ocorrência de P. ailyae, a genética de suas populações e o fluxo gênico interpopulacional; adicionalmente, conhecer um pouco da história natural da espécie. Foram realizadas oito expedições, sendo visitadas 41 localidades de 10 estados brasileiros. Dentre estas localidades, em apenas 17 foram encontradas colônias ativas de P. ailyae, sendo coletados espécimes de 75 ninhos. Para identificar as linhagens mitocondriais presentes nas localidades amostradas, cinco regiões gênicas foram utilizadas (COI, CytB, 12S, 16S e COI-COII). Os níveis de polimorfismo estimados neste estudo mostraram COI como a região mais variável (11 haplótipos), seguido de CytB (sete haplótipos). Para os genes ribossomais, apenas algumas amostras foram analisadas, pois foram identificadas poucas diferenças entre as sequências. Todas as 31 amostras analisadas para o gene 12S apresentaram repetição/inserção de cinco bases a partir da posição 25 da sequência, resultado não observado nas demais espécies de Partamona analisadas. Os genes que forneceram maiores informações (COI e CytB) tiveram suas sequências concatenadas (1114pb) e para estas regiões, foram observados 13 haplótipos; destes, dois foram compartilhados e 11 caracterizados como exclusivos de localidades. A AMOVA demonstrou que 94,3% da variação genética é resultado de diferenças interpopulacionais, revelando uma XII elevada diferenciação entre as populações analisadas (ΦST = 0.9426; P = 0,000). Além disso, um indivíduo de cada colônia foi analisado para oito locos microssatélites, delineados para Melipona bicolor e Partamona helleri. As populações apresentaram moderada diferenciação interpopulacional (ΦST = 0,1491; P = 0,000). A análise de agrupamento identificou quatro grupos por meio do ΔK como sendo o modelo ideal, e através do STRUCTURE, foi verificado que todos os indivíduos das respectivas populações têm probabilidade de pertencer a mais de um grupo, corroborando o “Assignment test”, o qual indicou que apenas 50% das amostras foram corretamente identificadas à sua população de origem. Foi realizada análise da segregação fenotípica nas progênies de vários ninhos, revelando uma estrutura familial monogínica/monândrica. Para os dados mitocondriais, o teste de Mantel mostrou uma correlação significativa entre distância genética e distância geográfica (r = 0,2589; P = 0,0231). Já para os dados nucleares, esse teste não indicou correlação significativa entre as distâncias genéticas e geográficas (r = 0,2090; P = 0,0610). Os testes de Fs de Fu e R2 não apresentaram valores significativos. Na análise do Bayesian Skyline Plot (BSP), não foram observadas oscilações marcantes no tamanho efetivo das populações de P. ailyae, indicando estabilidade populacional ao longo do tempo considerado. Os valores do ΦST estimados para genes mitocondriais e para os microssatélites foram comparados, sendo detectadas evidências de dispersão sexo-assimétrica, em que as fêmeas são as responsáveis pela ocupação de áreas, e os machos constituem o sexo dispersor. Além disso, são apresentados alguns aspectos relevantes da história natural de P. ailyae.

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