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The population structure of Thamnolia subuliformis and Dicranum elongatum in northeastern coastal regions of Wapusk National Park, Manitoba.Cassie, David M. 08 January 2007 (has links)
The population structure of a lichen, Thamnolia subuliformis and a moss, Dicranum elongatum, was examined in northeastern regions of Wapusk National Park. With the use of microsatellite molecular markers, it was reported that the sterile lichen had a level of variation similar to that of a sexually reproducing species. The variation reported for the moss, where sporophytes were not encountered, supported subdivided populations. It was concluded that these species have the genetic resources necessary to adapt to changing environmental conditions.
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Genealogy ReconstructionRiester, Markus 02 July 2010 (has links) (PDF)
Genealogy reconstruction is widely used in biology when relationships among entities are studied. Phylogenies, or evolutionary trees, show the differences between species. They are of profound importance because they help to obtain better understandings of evolutionary processes. Pedigrees, or family trees, on the other hand visualize the relatedness between individuals in a population. The reconstruction of pedigrees and the inference of parentage in general is now a cornerstone in molecular ecology. Applications include the direct infer- ence of gene flow, estimation of the effective population size and parameters describing the population’s mating behaviour such as rates of inbreeding.
In the first part of this thesis, we construct genealogies of various types of cancer. Histopatho- logical classification of human tumors relies in part on the degree of differentiation of the tumor sample. To date, there is no objective systematic method to categorize tumor subtypes by maturation. We introduce a novel algorithm to rank tumor subtypes according to the dis- similarity of their gene expression from that of stem cells and fully differentiated tissue, and thereby construct a phylogenetic tree of cancer. We validate our methodology with expression data of leukemia and liposarcoma subtypes and then apply it to a broader group of sarcomas and of breast cancer subtypes. This ranking of tumor subtypes resulting from the application of our methodology allows the identification of genes correlated with differentiation and may help to identify novel therapeutic targets. Our algorithm represents the first phylogeny-based tool to analyze the differentiation status of human tumors.
In contrast to asexually reproducing cancer cell populations, pedigrees of sexually reproduc- ing populations cannot be represented by phylogenetic trees. Pedigrees are directed acyclic graphs (DAGs) and therefore resemble more phylogenetic networks where reticulate events are indicated by vertices with two incoming arcs. We present a software package for pedigree reconstruction in natural populations using co-dominant genomic markers such as microsatel- lites and single nucleotide polymorphism (SNPs) in the second part of the thesis. If available, the algorithm makes use of prior information such as known relationships (sub-pedigrees) or the age and sex of individuals. Statistical confidence is estimated by Markov chain Monte Carlo (MCMC) sampling. The accuracy of the algorithm is demonstrated for simulated data as well as an empirical data set with known pedigree. The parentage inference is robust even in the presence of genotyping errors. We further demonstrate the accuracy of the algorithm on simulated clonal populations. We show that the joint estimation of parameters of inter- est such as the rate of self-fertilization or clonality is possible with high accuracy even with marker panels of moderate power. Classical methods can only assign a very limited number of statistically significant parentages in this case and would therefore fail. The method is implemented in a fast and easy to use open source software that scales to large datasets with many thousand individuals.
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Conservation genetics of a Gondwana relict rainforest tree, Nothofagus moorei (F. Muell.) KrasserSchultz, Lee January 2008 (has links)
Nothofagus moorei is a long-lived, Gondwana relict cool temperate rainforest tree. Nothofagus-dominated rainforests were widespread across much of eastern Australia during the mid-Tertiary but today, N. moorei occurs only as a series of disjunct, isolated populations in south-east Queensland and northern New South Wales. Clonal regeneration via coppicing is reported to be a common feature of most N. moorei populations, while successful sexual regeneration is believed to be rare, occurring largely only in niches with high light levels and limited competition. While clonal propagation enables population persistence and individual longevity, it cannot generate novel genotypes. Isolated populations, potentially high levels of clonality, low-potential for successful sexual regeneration, long-lived individuals and predicted global warming effects make N. moorei vulnerable to local, if not total, population extinction. The current study aimed to assess the relative conservation status of extant N. moorei populations in order to develop appropriate conservation management strategies for long-term population persistence. Levels of genetic diversity and population structure were examined across the remaining natural distribution of N. moorei using nuclear amplified fragment length polymorphism (AFLP), microsatellite and chloroplast DNA markers. In total 607 individuals were sampled from 20 populations and 5 geographical regions: Lamington/Border Ranges, Ballow, Dorrigo/New England, Werrikimbe and Barrington. Genetic results were then analysed to assess conservation status of each population and geographical region. Microsatellite and AFLP data identified comparatively high levels of genetic diversity in all remnant populations sampled. The prevalence of coppicing in the northern Lamington/Border Ranges populations appears to have had little impact on relative levels of genetic diversity, heterozygosity or population structure. Population differentiation was limited, with the majority of genetic variation retained within populations, no regional structuring and high levels of admixture. Analysis of cpDNA variation showed that the three Dorrigo/New England populations were divergent from all other populations, suggesting an ancient divergence in N. moorei prior to Pleistocene glaciations. While levels of genetic diversity were essentially the same across all populations, Bayesian analysis of genetic structure did identify four populations with differing gene pool proportions which would be important to include in conservation efforts in addition to individuals from other populations. Similarly, individuals from four significantly differentiated groups identified using traditional F-statistics suggests individuals from each of these four groups should be included in future conservation plans. In order to maintain ancient chloroplast lineages, populations from the Dorrigo/New England region should also be assigned special conservation value. Populations of N. moorei appear to have retained significant levels of genetic diversity and show little population divergence in spite of marked reductions in the natural distribution since the Early Miocene. Sampling of these ancient trees however, suggests current levels of diversity in N. moorei actually reflect past diversity and differentiation, and that there have been insufficient generations since the historical contraction in distribution for genetic diversity to be adversely affected and regional differentiation to evolve. Long-term persistence of N. moorei is still threatened by future accelerated climate change and the limited preferred habitat that remains where N. moorei can expand its range. While the ability to regenerate clonally may enable long-term persistence of N. moorei, populations are still likely to continue to decline as climatic conditions will increasingly favour sub-tropical and warm temperate species across much of N. moorei's northern distribution. Southern populations of N. moorei, in contrast, could expand their ranges into eucalypt woodlands as predicted climate becomes warmer and wetter. However, this will ultimately be determined by the frequency of fires, with increased fire frequencies favouring the expansion of eucalypts and contraction and possible local population extinction of N. moorei dominated cool temperate rainforests.
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Programmed cell death and genetic stability in conifer embryogenesis /Helmersson, Andreas, January 2007 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 5 uppsatser.
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Microsatellite genotyping of contributing broodstock and selected offspring of Haliotis midae submitted to a growth performance recording schemeRuivo, Nicola Ribeiro 12 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: The indigenous abalone Haliotis midae is one of the most remarkable and highly exploited species
of marine molluscs in South Africa. It is the only species of southern African Haliotidae to be
commercially reared and has been successfully cultured for almost two decades. Its short history of
domestication along with market demands and the need to develop efficiency in the production
process has resulted in an increased interest in the possible genetic improvement of this species.
The unhurried growth rate associated with H. midae is a cause of particular concern to the industry,
predominantly with regards to profitability and competitiveness in the market place. A modest
amount of work has so far been directed at establishing a means of enhancement for selective
breeding on the commercial level. Genetics plays a key role in the establishment of successful
improvement programmes in various aquaculture species. The aim of this study was to develop
species-specific microsatellite markers for the abalone and subsequently perform parentage
assignment on farm produced animals entered into a growth performance recording scheme.
Animals were obtained from the hatcheries of three commercial abalone farms situated in the
Walker Bay region in the Western Cape.
Microsatellites were isolated using the enrichment-based FIASCO method, and characterised into
perfect, imperfect and compound repeats according to the structural nature of their repetitive units.
From the partial gDNA libraries obtained and 365 screened colonies, a total of 54 loci were located.
PCR primers were designed for 36 markers and the 15 primer pairs that displayed loci with the
highest level of polymorphism were subsequently chosen for fluorescent labelling. The markers
were tested on a subset of 32 wild H. midae individuals to determine their usefulness and efficiency
in genotyping. Five markers, along with five others that were previously designed, were chosen for
assigning parentage to the animals submitted to the performance recording scheme. Three thousand
offspring from each of the three participating farms were equally divided and reared at five different
locations. From each location 20 fast growing and 20 slow growing juveniles, as well as the
broodstocks, were sampled and genotyped using the ten chosen microsatellite loci. Two farms had
60% of offspring unambiguously assigned to a single parental couple. Assignments showed
patterns of dominant male and female brooders, but no trend in brooders specifically contributing to
fast or slow growing offspring. Parentage assignment for the third farm was, however, unsuccessful
due to lack of broodstock data. In future, screening of all available broodstock will ensure
acquisition of relevant pedigree information. The results obtained in this study are an initial step in
the development of a genetic improvement programme for commercial Haliotis midae. / AFRIKAANSE OPSOMMING: Die inheemse skulpvis Haliotis midae is een van die mees merkwaardige en hoogs oorbenutte
mariene slakspesies in Suid-Afrika. Dit is die enigste suidelike Afrika Haliotidae spesie wat
kommersieel benut word en dit word al meer as twee dekades suksesvol geteel. Die spesie se kort
domestiseringsgeskiedenis, toenemende mark aanvraag en die behoefte om meer effektiewe
produksie daar te stel, het gelei tot toenemende belangstelling in die moontlike genetiese
verbetering van die spesie. Die stadige groeitempo geassosieer met H. midae is veral ‘n punt van
kommer vir die industrie, veral in terme van winsgewendheid en kompetering in die markplek.
Minimale werk is sover gedoen in die daarstelling van verbetering deur selektiewe teling op ‘n
kommersiële skaal. Genetika speel ’n sleutelrol in die daarstelling van suksesvolle
verbeteringsprogramme van verskeie akwakultuur spesies. Die doel van hierdie studie was om
spesie-spesifieke mikrosatelliet merkers vir perlemoen te ontwikkel en vervolgens
ouerskapsbepaling van kommersiële diere, wat deelneem aan ‘n groeiprestasie aantekenstelsel, uit
te voer. Diere is voorsien deur die teelstasies van drie kommersiële perlemoenplase geleë in die
Walker Bay omgewing in die Wes-Kaap.
Mikrosatelliete is geïsoleer deur die verrykings-gebaseerde FIASCO metode, en gekarakteriseer as
perfekte, onderbroke of saamgestelde herhalings gebaseer op die strukturele aard van die herhalings
eenhede. Vanaf die gedeeltelik gDNA biblioteke wat bekom is en 365 gesifte kolonies, is ‘n totaal
van 54 loki opgespoor. PKR inleiers is ontwerp vir 36 merkers en die 15 inleierpare, wat loki met
die hoogste polimorfisme geamplifiseer het, is vervolgens geselekteer vir fluoreserende merking.
Die merkers is getoets op ’n kleiner groep van 32 natuurlike H. midae individue om hulle
bruikbaarheid en genotiperingseffektiwiteit te bepaal. Vyf merkers is saam met vyf reeds
ontwikkelde merkers gekies vir ouerskapsbepaling van die diere in die prestasie aantekenstelsel.
Drieduisend nageslag diere vanaf elkeen van die drie deelnemde plase is gelykop verdeel en
grootgemaak op die vyf verskillende lokaliteite. ‘n Monster van 20 vinnig groeiende en 20 stadig
groeiende jong perlemoen, sowel as broeidiere, is vanaf elke lokaliteit geneem en gegenotipeer deur
middel van die 10 geselekteerde mikrosatelliet loki. Sestig persent van twee van die plase se
nageslag is onteenseglik toegesê aan ‘n enkele ouerpaar. Ouerskapstoekenning het patrone van
dominante vroulike en manlike broeidiere getoon, maar geen tendens in terme van bydrae tot vinnig
en stadig groeiende nageslag kon gevind word nie. Ouerskapstoekenning vir die derde plaas was
onsuksesvol as gevolg van ’n gebrek aan data vir die broeidiere. In die toekoms sal genotipering
van alle beskikbare broeidiere die daarstelling van relevante stamboominligting verseker. Die
resultate verkry in hierdie studie verteenwoordig ‘n eerste stap in die ontwikkeling van ’n genetiese
verbeteringsprogram vir kommersiële Haliotis midae.
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Microsatellite markers to identify two species of Tilapiine fish, Oreochromis mossambicus (Peters) and O. niloticus (Linnaeus)Esterhuyse, M. M. 03 1900 (has links)
Thesis (MScAgric)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: Forming part of a conservation programme, this study was concerned with two
species of Cichlid fish (Oreochromis mossambicus and O. ni/oticus), which were
brought into contact with each other by unnatural ways. They are now
hybridizing to some extent and there is also evidence that the foreign O. ni/oticus
may out compete the native O. mossambicus. To cast light on what the current
distribution is of both these species and the hybrids in Southern Africa, it is
important to identify specimens very accurately.
In attempting to find genetic markers to distinguish between two species of
Cichlids we tested 20 microsatellite dinucleotide (CAn) repeats during a
preliminary study and found five of these promising to exhibit little intra-specific
genetic diversity but large genetic variation between species. We amplified these
five loci in 145 individuals from 10 populations, which included the two species
and their hybrids. Exact sizes of the fragments were determined using an
automated DNA sequencer.
Between the two species, allele sizes were overlapping, but when data were
analyzed by statistical models, the differences could be seen for populations,
however on individual level there was overlap between the species. The hybrids
were found to be intermediate positioned between the two pure species. Our
attempt to assign individuals to populations provided doubtful results. Thus,
using this set of markers, populations can be ascribed to one of these species,
but not individuals by themselves. / AFRIKAANSE OPSOMMING: As deel van 'n natuurbewarings program, word daar in hierdie studie twee
spesies van vis ondersoek was in kontak met mekaar gekom het op onnatuurlike
wyse. Hierdie twee visspesies vanuit die CICHLIDAEfamilie (Oreochromis
mossambicus en 0. ni/oticus) kan hibridiseer wanneer hul saam voorkom, maar
dit is ook bekend dat die uitheemse O. ni/oticus die inheemse O. mossambicus
kan bedreig in terme van leefruimte, kos en broeispasie. Om die voorkoms van
hibriede tussen die twee spesies te ondersoek in Suider Afrika se varswater
opvangsgebiede, is dit baie belangrik om individue baie akkuraat te identifiseer.
In hierdie poging om genetiese merkers te vind wat die twee spesies van mekaar
onderskei, het ons 20 mikrosateliet di-nulkleotied (CAn) herhalende volgordes op
verskillende loci ondersoek. Vyf daarvan het belowend voorgekom om as spesie
spesifieke merkers te dien. Die fragmente op die vyf loci is ge-amplifiseer in 145
individue vanuit 10 populasies. Presiese groottes van die fragmente is bepaal
met behulp van 'n ge-outomatiseerde DNA volgorde bepaler waarna genotiepes
vir elke individu toegeken is.
Tussen die twee spesies het alleel groottes oorvleuel, maar wanneer data geanaliseer
word met behulp van statistiese metodes, was verskille tussen die
spesies duidelik op populasie vlak. Die hibriede het intemediêr tussen die twee
spesies voorgekom. Dus met behulp van hierdie stel merkers kan onderskei
word tussen die twee spesies op populasie vlak, hoewel individue nie op sig self
identifiseer kan word nie.
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Variabilidade genética e química entre e dentro de populações de Casearia sylvestris Sw. (Salicaceae) no estado de São PauloCavallari, Marcelo Mattos [UNESP] 22 August 2008 (has links) (PDF)
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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)
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Mapeamento molecular do loco Rpp5 de resistência à ferrugem asiática da sojaMorceli, Thaiza Galhardo Silva [UNESP] 04 August 2008 (has links) (PDF)
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morceli_tgs_dr_jabo.pdf: 699244 bytes, checksum: f1671e3db3a2b611f86d79aaccfe36e0 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A ferrugem asiática da soja, causada pelo fungo Phakopsora pachyrhizi (Sidow & P. Sidow) foi relatada no Brasil ao final da safra 2001 e já nas safras seguintes, ocasionou severas perdas de produtividade. Cinco genes de resistência à ferrugem asiática da soja (Rpp1 a Rpp5) estão descritos na literatura. O objetivo geral deste trabalho foi identificar marcadores moleculares microssatélites ligados ao gene de resistência a P. pachyrhizi presente na linhagem de soja PI 200526. Uma população de plantas F2 derivada do cruzamento entre esta linhagem e a cultivar suscetível Coodetec 208, foi artificialmente inoculada e avaliada quanto à sua reação de resistência à ferrugem. Marcadores microssatélites foram testados nos genitores e em dois bulks contrastantes para possibilitar a identificação de possíveis marcadores ligados. Os três marcadores polimórficos que foram caracterizados como potencialmente associados com a resistência à ferrugem asiática foram, posteriormente, avaliados em toda a população. A resistência comportou-se como governada por um gene com dominância completa. O gene de resistência da PI 200526 foi mapeado no grupo de ligação N da soja, estando próximo ao marcador Sat_166. Existe grande possibilidade de que o gene mapeado neste estudo corresponda ao novo loco de resistência à ferrugem asiática da soja, denominado de Rpp5, recentemente descrito. / The Asian soybean rust caused by the Phakopsora pachyrhizi (Sidow & P. Sidow) fungus was related in Brazil at the end of 2001 crop year, and already in the following seasons, caused severe losses in productivity. Five distinct resistance genes to Asian rust (Rpp1 to Rpp5) are described. The main objective of this work was to identify microsatellite markers linked to a resistance gene to P. pachyrhizi present in the soybean line PI 200526. One population of F2 plants originated from the cross between this resistant line and the suscetible cultivar Coodetec 208 was artificially inoculated and evaluated for the Asian rust resistance. Microsatellite markers were tested on parents and in the two contrasting bulks to enable the identification of linked markers. The three polymorphic markers that were identified potentially associated with resistance to Asian rust were then evaluated throughout the progeny. The resistance showed to be governed by a gene with complete dominance. The resistance gene of PI 200526 was mapped on the soybean linkage group N, being close to Sat_166 marker. Possibly, the gene mapped on this linkage group is part of the new locus of resistance to Asian soybean rust, called Rpp5, recently described.
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Comportamento reprodutivo de espécies de Trypargilum e análises de parentesco genético intranidal e genética de populações de Trypoxylon (Trypargilum) albitarse (Hymenoptera: Crabronidae)Bergamaschi, Antônio Carlos Bragato 23 August 2013 (has links)
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Previous issue date: 2013-08-23 / Financiadora de Estudos e Projetos / The genus Trypoxylon consists of solitary wasps that build mud nests or nest in preexisting cavities, which brood cells positioned linearly are stored with paralyzed spiders. The male in species of the subgenus Trypargilum presents a singular behavior among Hymenoptera, playing the role of guard in active nests, which guarantees repeated copulations with the partner that interacts, especially before oviposition. It is expected that this behavior increases the chances of reproductive success of the guarding male. However, the constant presence of satellite males in nesting areas, associated to reports obtained in behavioral studies that pointed the receptivity of females assisted by a guarding male to extra-pair copulations, lay doubts in the effectiveness of reproductive tactics adopted by the guard. The aim of this study was to contribute to the knowledge of natural history of Trypoxylon (Trypargilum) species, through behavioral records, genetic analyzes of intranidal relatedness and analyzes of diversity and population structure. The nesting behavior of Trypoxylon agamemnon, Trypoxylon aurifrons and Trypoxylon nitidum in trap nests was recorded, mainly focusing on the interaction between the guarding male and the nesting female, beyond the role of the satellite male, who was constantly positioned near active nests. Genetic analysis of intranidal relatedness using species-specific microsatellite loci for Trypoxylon albitarse indicated that this species has a predominantly monogamous mating system, although extra-pair copulations have been detected. Since little is known about the population genetics of this group of wasps, we also present data from the genetic diversity and structure of five populations of T. albitarse, sampled in four states in Brazil, which indicated high levels of genetic diversity and significantly population structure. / O gênero Trypoxylon e constituido de vespas solitárias que constroem ninhos de barro ou nidificam em cavidades preexistentes, onde células de cria dispostas linearmente são estocadas com aranhas paralisadas. O macho em especies do subgênero Trypargilum apresenta um comportamento singular entre os Hymenoptera, exercendo o papel de guarda em ninhos ativos, o que lhe garante copulas repetidas com a parceira que interage, especialmente antes da oviposição. E de se esperar que este comportamento aumente as chances de sucesso reprodutivo do macho guarda. No entanto, a presença constante de machos patrulheiros em áreas de nidificação, aliada a relatos de estudos comportamentais que apontaram a receptividade de fêmeas já assistidas por um macho guarda a copulas extrapar, coloca em duvida a efetividade da tática reprodutiva adotada pelo guarda. O objetivo deste estudo foi contribuir para o conhecimento da historia natural de especies de Trypoxylon (Trypargilum), através de registros comportamentais, analises genéticas de parentesco intranidal e analises de diversidade e estruturacao populacional. O comportamento de nidificacao de Trypoxylon agamemnon, Trypoxylon aurifrons e Trypoxylon nitidum foi registrado em ninhos-armadilha, focando principalmente a interação entre o macho guarda e a fêmea construtora, alem do papel do macho patrulheiro, que esteve constantemente posicionado próximo a ninhos ativos. Analises genéticas de parentesco intranidal utilizando locos microssatelites especie específicos de Trypoxylon albitarse indicaram que esta especie possui um sistema de acasalamento predominantemente monogâmico, apesar de copulas extrapar terem sido detectadas. Uma vez que pouco se conhece sobre a genética de populações desse grupo de vespas, apresentamos também dados referentes a diversidade e estrutura genéticas de cinco populações de T. albitarse, provenientes de quatro estados do Brasil, os quais indicaram altos índices de diversidade genética e estruturação populacional significativa.
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Diversidade genética em populações de Myracrodruon urundeuva Fr. All., sob diferentes tipos de perturbação antrópica /Perez Viegas, Michele. January 2009 (has links)
Resumo: Os marcadores de microssatélites tem sido utilizados com grande freqüência como ferramenta efetiva para estudos de estrutura genética de populações, fluxo gênico, parentesco e para quantificar os efeitos da fragmentação de habitats e guiar estratégias de conservação e melhoramento genético. Este trabalho teve como objetivo avaliar a diversidade genética e o sistema reprodutivo em progênies de duas populações de Myracrodruon urundeuva, procedentes de Aramina-SP e Selvíria-MS, assim como verificar os efeitos da ação antrópica sobre estas populações. Foram avaliadas 25 progênies de cada população, cada uma com 17 a 20 indivíduos, sendo analisados oito locos polimórficos de regiões microssatélites. Observouse 118 alelos nas duas populações e o número efetivo por loco ( e A ∧ = 4,05) foi inferior ao número médio de alelos por loco ( ∧A= 14,75), indicando elevado número de alelos em baixa freqüência. O índice de fixação (F = 0,210 e 0,107, respectivamente para Aramina e Selvíria) foi positivo, relativamente alto e significativamente diferente de zero. A taxa de cruzamento multilocos ( ∧ m t = 1,000 e ∧ m t = 1,000) e unilocos ( ∧ s t = 0,989 e ∧ s t = 0,999) para as populações de Aramina e Selvíria, respectivamente, foram altos, confirmando que a espécie é obrigatoriamente de cruzamento. A diferença entre a taxa de cruzamento multilocos e unilocos indicam cruzamentos entre indivíduos aparentados na população de Aramina. 9 Entretanto, as duas populações apresentaram alta diversidade genética, o que as qualifica para utilização em programas de conservação e melhoramento genético da espécie. / Abstract: The microsatellite markers has been often employed as effective tool for studies of genetic structure of populations, gene flow, relationship and also for to quantify environmental fragmentation effects and to outline strategies for conservation and breeding. This study aimed to evaluate the genetic diversity and mating system in progenies of two Myracrodruon urundeuva populations from Aramina-SP and Selvíria-MS, as well as verify the effects of antropic action on these populations. From each population were evaluated 25 progenies, with 15-20 individuals each, using genetic data from 8 microsatellite loci. There was 118 alleles in both populations and the actual number per locus ( e A ∧ = 4.05) was lower than the average number of alleles per locus ( ∧A = 14.75), indicating high number of alleles in low frequency. The fixation index (F = 0,210 e 0,107, respectively for Aramina and Selvíria) was positive, relatively high and significantly different from zero. The multilocus outcrossing rate ( ∧ m t = 1,000 e ∧ m t = 1,000) single-locus ( ∧ s t = 0,989 e ∧ s t = 0,999) for the populations for Aramina and Selvíria, respectively, they were high, confirming that the species is obligatorily for outcrossing. The difference between the multilocus outcrossing rates and single-locus outcrossing rate indicates mating among relatives in the Aramina population. Meanwhile, the 11 two populations had high genetic diversity, which qualifies them for use in programs for conservation and breeding of this species. / Orientador: Mário Luiz Teixeira de Moraes / Coorientador: Cristina Lacerda Soares Petrarolha Silva / Banca: Alexandre Magno Sebbenn. / Banca: Karina Martins. / Mestre
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