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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.
41

Modification of the structure of wild boar populations by hunting and influence on reproductive processes / Modification de la structure des populations de sangliers par la chasse et influence sur les processus de reproduction

Gayet, Thibault 13 July 2018 (has links)
Le sanglier (Sus scrofa scrofa) est une espèce à part entière. C'est une espèce de gibier particulièrement appréciée des chasseurs, un cauchemar pour les agriculteurs et un sujet de débat pour la société en général. La multiplication par dix des populations au cours des dernières décennies en France et dans toute l'Europe, malgré une pression de chasse accrue, a engendré de nombreux conflits entre les humains et la faune sauvage. Le sanglier est responsable de grandes pertes économiques dues aux collisions avec les véhicules, à la transmission de maladies et de dommages aux cultures et écosystèmes. L'amélioration des stratégies de gestion devient un intérêt majeur pour éviter, ou contrôler, de tels conflits. La récolte d'informations sur l'espèce problématique est un premier pas vers de bonnes stratégies de gestion. L'objectif de mon travail est, dans un premier temps, de caractériser le système d’appariement du sanglier et d'identifier certains paramètres influençant les processus de reproduction, notamment la chasse. Dans un deuxième temps, mon travail se concentre sur l'étude de l'influence du système d’appariement sur les traits d'histoire de vie du sanglier. Mes recherches sont basées sur l'étude de plusieurs populations contrastées dans leurs pratiques de chasse et sur des données longitudinales d'une population intensivement suivie. L'étude est basée sur des données recueillies sur des sangliers tués à la chasse. Les génotypes ont été obtenus pour les femelles gestantes et leur portée et des analyses de paternité ont été réalisées pour mesurer le nombre de pères dans une portée et estimer les taux de paternité multiples (proportion de portées engendrées par plus d'un père). J'ai été en mesure de montrer que le système d’appariement est principalement de promiscuite (plusieurs mâles s'accouplent avec plusieurs femelles) contrastant avec la polygynie (un mâle dominant monopolisant un groupe de femelles) habituellement décrite chez cette espèce. De plus, les processus de reproduction, estimés par le nombre de partenaires d'une femelle et les taux de paternité multiples, sont influencés par les variations de chasse dans une population. J'ai aussi montré que le nombre de pères avait un effet positif sur la fécondité des femelles. Des taux élevés de paternité multiple et une grande diversité génétique ont été constatés ensemble dans une population fortement chassée, ce qui suggère que la paternité multiple peut tamponner les goulots d'étranglement annuels. Cependant, l'augmentation du nombre de père n'est pas associée à une augmentation de la variation intraportée / The wild boar (Sus scrofa scrofa) is a peculiar species. It is an appreciated game species for hunters, a nightmare for farmers and a subject of debate for the society in general. The tenfold increase of the population over the last decades in France and all over Europe, despite increased hunting pressure, generated great human-wildlife conflict. The wild boar is responsible for great economic losses due to vehicle collision, diseases transmission and damaged crops and ecosystems. Improving management strategies becomes a prime interest to avoid such conflicts, or at least keep them under control. Obtaining information on the species is a first step toward good management strategies. The objective of my work is, in a first part, to characterize the mating system of the wild boar and to identify some parameters, especially hunting, influencing the reproductive processes. The second part focus on the investigation of the influence of the mating system on wild boar life history traits. My researches are based on the study of several populations contrasting in their hunting practices and on longitudinal data of a highly monitored population. The study is based on data collected on wild boars killed by hunting. Genotypes were obtained for pregnant females and their litter and paternity analyses were realized to measure the number of fathers in a litter and estimate multiple paternity rates (proportion of litter sired by more than one father). I was able to show that the mating system is mainly promiscuous (several males mate with several females) contrasting with the polygyny (a dominant male monopolizing a group of females) usually described in this species. Moreover, reproductive processes, estimated by the number of mates of a female and the multiple paternity rates, are influenced by hunting variations in a population. I also showed that number of fathers has positive effect on female fecundity. High rates of multiple paternity together with high genetic diversity were found in a heavily hunted population, suggesting multiple paternity may buffer yearly bottlenecks. However, the increase of number of fathers is not associated with increase of within-litter variation
42

Genetic variation and sexual system evolution in the annual mercuries

Obbard, Darren J. January 2004 (has links)
The Mercurialis annua L. (Euphorbiaceae) species complex comprises a group of closely related lineages that present a wide range of sexual-systems, making it a valuable model for the study of plant sexual-system evolution. Within this polyploid complex, diploid populations are dioecious, and polyploid populations either monoecious or androdioecious (males coexist with functional hermaphrodites). The primary aim of this thesis was to use patterns of genetic diversity to elucidate the evolutionary origin and maintenance of the sexual-system diversity in M. annua. The phylogeny of the M. annua complex was reconstructed using chloroplast and ITS DNA sequence. This, in conjunction with morphometric analysis, showed that both hexaploid M. annua, and a novel species from the Canary Islands (newly described here as Mercurialis canariensis), were allopolyploid in origin. Such an origin for hexaploid M. annua suggests that androdioecy may have been able to arise in this group as a consequence of hybridisation between a monoecious lineage, tetraploid M. annua, and a dioecious lineage, M. huetii. Artificial crosses were used to show that hexaploid M. annua has disomic marker inheritance, and a statistical approach was developed to quantify genetic diversity and differentiation in polyploids with disomic inheritance. Strong gradients in genetic (allozyme) diversity at a pan-European scale were used to infer the existence of separate glacial refugia for dioecious and monoecious races of M. annua, at the eastern and western ends of the Mediterranean basin, respectively. A metapopulation model had previously been proposed to explain the ecological maintenance of androdioecy in M. annua. Here, population-level patterns of genetic diversity were used as an indirect test of this model. The discovery of lower within-population diversity, and of greater genetic differentiation between populations, for monoecious populations than for androdioecious populations was consistent with the metapopulation model, and suggests that androdioecy is maintained by the occurrence of regular local extinction.
43

Melhoramento em progênies de seringueira [Hevea brasiliensis (Willd. Ex Adr. de Juss.) Muell.- Arg.] por caracteres quantitativos e marcadores moleculares do tipo SSR em duas populações de diferentes procedência /

Dourado, Cecília Luzia. January 2016 (has links)
Orientador: Mario Luiz Teixeira de Moraes / Resumo: O objetivo principal do trabalho foi o de quantificar a variabilidade genética em progênies de seringueira fundamentando-se na avaliação de caracteres quantitativos e na caracterização molecular do tipo microssatélites (SSR). A primeira população do estudo é originária da floresta primária de Rio Branco- Acre (população selvagem-PS), e a outra, trata-se de uma população, originada de matrizes clonais (população melhorada-PM). Encontram-se instaladas na forma de teste de progênies na Fazenda de Ensino, Pesquisa e Extensão da Faculdade de Engenharia de Ilha Solteira/UNESP (FEPE), localizada em Selvíria, MS. Para as duas populações foram avaliados os seguintes caracteres silviculturais de crescimento, altura (ALT), altura comercial (AC), diâmetro médio de copa (DMC), forma do fuste (FOR), perímetro do caule (PAP e P50) e produção de borracha seca (PBS), aos oito (PM) e 23 (PS) anos de idade. O delineamento experimental utilizado foi o de blocos casualizados, compostos por 31 famílias, quatro repetições e parcelas lineares de 10 plantas, no espaçamento de 3 x 3 m (PM). Para PS o delineamento experimental foi de blocos causalizados com 37 famílias distribuídas em três repetições, de forma desbalanceada com no máximo 10 plantas por progênies no espaçamento de 5 x 3 m (PS). As estimativas dos parâmetros genéticos foram feitas utilizando-se a metodologia de modelo linear misto univariado aditivo REML/BLUP e ganhos na seleção pelo método índice multiefeitos (IME). O DNA genômico foi e... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The main objective of this work is to quantify the genetic variability in progenies of rubber tree, based on the quantitative characterization and the molecular characterization of the microsatellite type (SSR). The first population of the study originated in the primary forest of Rio Branco-Acre (wild population-PS), and the other population is a population originated from clonal matrices (improved population-PM). They are installed as progeny tests at the Teaching, Research and Extension Farm, That belongs to Engeneering College of the Julio Mesquita Filho State University of São Paulo, In Selvira, State of South Mato Grosso Brazil. For the two populations, the following silvicultural characteristics of growth, height (ALT), commercial height (AC), average crown diameter (DMC), stem shape (FOR), stem perimeter (PAP and P50) and dry rubber yield (PBS) at eight (PM) and 23 (PS) years old. The experimental design consisted of randomized blocks, composed of 31 families, four replications and linear plots of 10 plants, spaced 3 x 3 m (MP). For PS the experimental design was of causalized blocks with 37 families distributed in three replications, unbalanced with a maximum of 10 plants per progeny in the spacing of 5 x 3 m (PS). Estimates of the genetic parameters were made using the mixed linear univariate model (REML / BLUP) methodology and gains in selection by multi-effects index (MEI). Genomic DNA was extracted, quantified and genotyped for the two study populations. The anal... (Complete abstract click electronic access below) / Doutor
44

Caracterização e comparação da diversidade genética de populações de Eucalyptus grandis por meio de marcadores moleculares e características quantitativas / Characterization and comparison of genetic diversity of populations of Eucalyptus grandis using molecular markers and quantitative traits

Miranda, Aline Cristina [UNESP] 27 September 2016 (has links)
Submitted by ALINE CRISTINA MIRANDA null (alinemiranda7@bol.com.br) on 2016-11-17T14:08:46Z No. of bitstreams: 1 Tese_alinemiranda.pdf: 1667580 bytes, checksum: 7967a917b23de82f09723bb1a5bab71d (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-11-23T16:19:54Z (GMT) No. of bitstreams: 1 miranda_ac_dr_bot.pdf: 1667580 bytes, checksum: 7967a917b23de82f09723bb1a5bab71d (MD5) / Made available in DSpace on 2016-11-23T16:19:54Z (GMT). No. of bitstreams: 1 miranda_ac_dr_bot.pdf: 1667580 bytes, checksum: 7967a917b23de82f09723bb1a5bab71d (MD5) Previous issue date: 2016-09-27 / O objetivo desse estudo foi explorar a variabilidade genética existente entre e dentro de procedências e progênies da população estudada, conhecendo a estrutura genética da população de melhoramento, estimando parâmetros genéticos de caracteres quantitativos de crescimento e determinando a origem das populações de melhoramento de Eucalyptus grandis. O teste de progênies e procedências de Eucalyptus grandis com 153 progênies de polinização aberta, oriundas de dez procedências foi implantado em Anhembi como parte da rede experimental Projeto Cooperativo Populações Núcleo, sendo o delineamento experimental utilizado de blocos casualizados com quatro repetições e seis plantas lineares. A mensuração dos caracteres quantitativos como diâmetro à altura do peito, altura total das árvores, volume e sobrevivência ocorreram aos 12, 24, 36, 48 e 60 meses e as análises foram realizadas via RELM/BLUP. Para a avaliação do sistema de reprodução e identificação da diversidade genética existente nas procedências brasileiras, foram selecionadas 981 plantas para análise de nove locos microssatélites e para determinação das origens da espécie estudada foi realizado a genotipagem de 254 plantas de 18 populações da Austrália. Nas análises individuais em todos os períodos de avaliação, os caracteres de produção apresentaram-se significativos a um grau de liberdade pelo teste LRT, indicando a existência de variabilidade genética a ser explorada pelo melhoramento genético, tanto entre como dentro de progênies. Houve uma redução dos valores de herdabilidade individual para todas as características avaliadas aos 12 meses para 60 meses de mensuração. O valor de repetibilidade individual ( ) obtido apresentou magnitude alta (0,78). Das 20 progênies selecionadas pela média harmônica da performance relativa dos valores genéticos (MHPRVG), 14 dessas estão presentes em todas as análises mostrando que a seleção com base apenas na análise de interação genótipos x anos, pode ser errônea e/ou não capitalizar genótipos importantes. Das dez procedências avaliadas, a seleção realizada pela MHPRVG proporcionou a seleção de progênies de seis procedências. Estimativa da taxa de cruzamento multiloco foi alta (0,994), esse resultado está dentro do padrão observado para a taxa de cruzamento em outras populações, mas significativamente diferente de 1,0, sugerindo um sistema misto de reprodução, combinando autofecundações e cruzamentos, com predominância de cruzamento. As estimativas de diferenciação genética entre as populações foram significativamente diferentes de zero. A combinação da origem de diferentes procedências brasileiras associadas à seleção, indica potencial de reprodução, sendo que, os indivíduos de diferentes procedências podem ser utilizados para compor uma nova geração. / To explore the genetic variability between and within provenances and progenies of the population studied, the aim of this study was to understand the genetic structure of the population of breeding, to estimate genetic parameters of quantitative traits of growth and determine the origin of breeding populations Eucalyptus grandis. The provenances test and progenies of Eucalyptus grandis with 153 open-pollinated progenies, ten provenances, was established at Anhembi, as part of the experimental network (PCPN), the experimental design was a design randomized block with linear plots. The measurement of quantitative traits diameter at breast height, total tree height, cylindrical volume and survival were evaluates at 12, 24, 36, 48 and 60 months, the analyzes were performed by RELM / BLUP and evaluation of mating system and identification the genetic diversity of Brazilian provenances, 981 plants were selected for analysis of nine microsatellite loci and to determine the origins of studied species was conducted genotyping of 254 samples from 18 populations of Australia. In the individual analysis in all evaluation, yield traits showed a significant degree of freedom for the LRT test, indicating the existence of genetic variability to be exploited by breeding, both between and within progenies. There was a reduction of individual heritability values for all characteristics evaluated at 12 months to 60 months of measurement. The individual value of repeatability ( r ˆ ) obtained showed high magnitude (0.78). We selected the best 20 progenies classified in terms of individual genetic value by MHPRVG, 14 progenies were found are present in all analyzes showing that the selection based only on the analysis of genotype x years can be erroneous and / or to capitalize important genotypes. Of the ten evaluated provenances, the selection made by MHPRVG provided the selection of six provenances progenies. Estimated multilocus outcrossing rate was high (0.994), this result is within the pattern observed for the outcrossing rate in other populations, but significantly different from 1.0, suggesting a mixed system of reproduction, combining selfing and crosses, especially cross. Estimates of genetic differentiation among populations were significantly different from zero. The combination of different origin Brazilian origins associated with the selection, indicates reproductive potential, is that individuals of different origins may be used to compose a new generation.
45

Melhoramento em progênies de seringueira [Hevea brasiliensis (Willd. Ex Adr. de Juss.) Muell.- Arg.] por caracteres quantitativos e marcadores moleculares do tipo SSR em duas populações de diferentes procedência / Improvement in rubber tree progenies [Hevea brasiliensis (Willd. ex Adr. Than Juss.) Muell. - Arg.] by quantitative characters and molecular markers type SSR in two populations of different origin

Dourado, Cecília Luzia [UNESP] 10 November 2016 (has links)
Submitted by Cecília Luzia Dourado (douradocl.cl@gmail.com) on 2017-05-23T14:32:39Z No. of bitstreams: 1 Cecília_Dourado_Tese_final.pdf: 2809054 bytes, checksum: 3b7bae6fc7d04f1ab484508fc4a7496d (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-05-23T18:22:13Z (GMT) No. of bitstreams: 1 dourado_cl_dr_ilha.pdf: 2809054 bytes, checksum: 3b7bae6fc7d04f1ab484508fc4a7496d (MD5) / Made available in DSpace on 2017-05-23T18:22:13Z (GMT). No. of bitstreams: 1 dourado_cl_dr_ilha.pdf: 2809054 bytes, checksum: 3b7bae6fc7d04f1ab484508fc4a7496d (MD5) Previous issue date: 2016-11-10 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O objetivo principal do trabalho foi o de quantificar a variabilidade genética em progênies de seringueira fundamentando-se na avaliação de caracteres quantitativos e na caracterização molecular do tipo microssatélites (SSR). A primeira população do estudo é originária da floresta primária de Rio Branco- Acre (população selvagem-PS), e a outra, trata-se de uma população, originada de matrizes clonais (população melhorada-PM). Encontram-se instaladas na forma de teste de progênies na Fazenda de Ensino, Pesquisa e Extensão da Faculdade de Engenharia de Ilha Solteira/UNESP (FEPE), localizada em Selvíria, MS. Para as duas populações foram avaliados os seguintes caracteres silviculturais de crescimento, altura (ALT), altura comercial (AC), diâmetro médio de copa (DMC), forma do fuste (FOR), perímetro do caule (PAP e P50) e produção de borracha seca (PBS), aos oito (PM) e 23 (PS) anos de idade. O delineamento experimental utilizado foi o de blocos casualizados, compostos por 31 famílias, quatro repetições e parcelas lineares de 10 plantas, no espaçamento de 3 x 3 m (PM). Para PS o delineamento experimental foi de blocos causalizados com 37 famílias distribuídas em três repetições, de forma desbalanceada com no máximo 10 plantas por progênies no espaçamento de 5 x 3 m (PS). As estimativas dos parâmetros genéticos foram feitas utilizando-se a metodologia de modelo linear misto univariado aditivo REML/BLUP e ganhos na seleção pelo método índice multiefeitos (IME). O DNA genômico foi extraído, quantificado e genotipado para as duas populações de estudo. As análises do sistema de reprodução e diversidade foram baseadas no modelo misto de reprodução e modelo de cruzamentos correlacionados. Foram detectadas diferenças significativas pelo teste da razão de verossimilhança na análise de deviance das procedências para os caracteres, diâmetro médio de copa (DMC), perímetro a 50 cm do solo (P50), perímetro a 1,30m do solo (PAP) e produção de borracha seca (PBS), para PM. Para população selvagem foram significativos, os caracteres ALT, DMC, P50 e PAP. Os caracteres que apresentaram maior magnitude para as herdabilidades foram a PBS, para população melhorada e PAP, PBS para a população selvagem, com herdabilidades acima de 60%. As estratégias de seleção de 50%, 40% e 22% dos indivíduos para o caractere PBS e PAP utilizando o índice multiefeitos revelaram de altos e baixos ganhos na seleção as duas populações. Para PM foi mais indicado a estratégia de seleção entre e dentro e para PS a seleção individual. Os ganhos obtidos na seleção foram de 54% para o caráter PBS na população melhorada e de 0,46% para o caráter PAP para população selvagem. A heterozigosidade observada foi de 0,839 a 0,747 para adultos e de 0,425 a 0,399 para as progênies, para as duas populações estudas. A taxa de cruzamento multiloco ( ) variou de 0,726 (PM) a 0,798 (PS), indicando que grande parte das sementes foram originadas por cruzamentos, mas houve presença de autofecundação, caracterizado por um sistema de reprodução misto. A endogamia apresentada foi gerada por cruzamentos correlacionados e não por autofecundação. Devido ao ao tamanho efetivo (Ne) menor que 4, resultou na necessidade de coletar-se sementes para fins de conservação genética, recuperação ambiental e melhoramento florestal de pelo menos 94 e 89 árvores, para PM e PS respectivamente. / The main objective of this work is to quantify the genetic variability in progenies of rubber tree, based on the quantitative characterization and the molecular characterization of the microsatellite type (SSR). The first population of the study originated in the primary forest of Rio Branco-Acre (wild population-PS), and the other population is a population originated from clonal matrices (improved population-PM). They are installed as progeny tests at the Teaching, Research and Extension Farm, That belongs to Engeneering College of the Julio Mesquita Filho State University of São Paulo, In Selvira, State of South Mato Grosso Brazil. For the two populations, the following silvicultural characteristics of growth, height (ALT), commercial height (AC), average crown diameter (DMC), stem shape (FOR), stem perimeter (PAP and P50) and dry rubber yield (PBS) at eight (PM) and 23 (PS) years old. The experimental design consisted of randomized blocks, composed of 31 families, four replications and linear plots of 10 plants, spaced 3 x 3 m (MP). For PS the experimental design was of causalized blocks with 37 families distributed in three replications, unbalanced with a maximum of 10 plants per progeny in the spacing of 5 x 3 m (PS). Estimates of the genetic parameters were made using the mixed linear univariate model (REML / BLUP) methodology and gains in selection by multi-effects index (MEI). Genomic DNA was extracted, quantified and genotyped for the two study populations. The analyzes of the breeding and diversity system were based on the mixed breeding model and correlated crosses model. Significant differences were detected by the likelihood ratio test in the deviance analysis for the characters, mean crown diameter (DMC), stem perimeter at 50 cm from soil (P50), stem perimeter at 1,30m from soil (PAP) and dry rubber yield (PBS) for PM. For wild populations were significant, the characters ALT, DMC, P50 and PAP. The characters that presented the greatest magnitude for the heritabilities were PBS, for improved population and PAP, PBS for the wild population, with heritabilities above 60%. The selection strategies of 50%, 40% and 22% of individuals for the PBS and PAP using the multi-effects index revealed high and low gains in the selection of the two populations. For PM it was more indicated the strategy of selection between and within and for PS the individual selection. The gains obtained in the selection were 54% for the PBS character in the improved population and 0,46% for the PAP character for the wild population. The observed heterozygosity was 0,839 to 0,747 for adults and 0,425 to 0,399 for the progenies, for the two populations studied. The multilocus crossing rate ( ) varied from 0,726 (MP) to 0,798 (PS), indicating that most of the seeds originated by crosses, but there was a presence of self-fertilization, characterized by a mixed mating system.The presented inbreeding was generated by correlated crosses and not by self-fertilization. Due to the effective size (Ne) of less than 4, it resulted in the need to collect seeds for purposes of genetic conservation, environmental recovery and forest improvement of at least 94 and 89 trees, for PM and PS respectively. / FAPESP: 2013/03074-5
46

Estrutura genética intrapopulacional e dispersão de pólen em Hancornia speciosa Gomes (Apocynaceae) / Intrapopulation genetic structure and pollen dispersal in Hancornia speciosa Gomes (Apocynaceae)

Costa, Camila Fernanda 23 March 2013 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2016-06-02T17:26:11Z No. of bitstreams: 2 Dissertação - Camila Fernanda Costa - 2013.pdf: 2572672 bytes, checksum: 54a6e93e72c746e4888a6f3583d4f3ac (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Erika Demachki (erikademachki@gmail.com) on 2016-06-02T17:49:46Z (GMT) No. of bitstreams: 2 Dissertação - Camila Fernanda Costa - 2013.pdf: 2572672 bytes, checksum: 54a6e93e72c746e4888a6f3583d4f3ac (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-06-02T17:49:46Z (GMT). No. of bitstreams: 2 Dissertação - Camila Fernanda Costa - 2013.pdf: 2572672 bytes, checksum: 54a6e93e72c746e4888a6f3583d4f3ac (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-03-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Hancornia speciosa (Apocynaceae) is a fruit species which has a wide distribution in areas of Cerrado vegetation type restricted sense. Its flowers have a complex pollination mechanism and unique, co-adapted to pollination by moths and butterflies and their fruits are dispersed by mammals large and medium-sized. It has high economic potential and its use has been conducted in an exploratory way. To implement conservation programs, breeding and enabling the commercial use of species, knowledge about the genetic variability, the spatial genetic structure, the reproductive system and gene flow in natural populations are needed. In this context, in the present study was performed the molecular characterization of the genetic variability in three stages of individuals (adults, juveniles and seedlings) and the assessment of genetic structure spatial (adults and juveniles), of the system of crossing and of the gene flow via pollen in a subpopulation of Hancornia speciosa located in the State Park of Serra de Jaragua, Jaragua-GO. To this end, 113 adults and 100 juveniles were sampled and georeferenced in an area of approximately 2.5ha. Of the total number of adults, 20 trees were selected matrices to obtain seedlings and formation of families of open pollination. Genomic DNA was obtained from the leaves of all individuals (adults, juveniles and seedlings) and was amplified with the use of seven microsatellite loci for obtaining of genotypes. The analyzes of genetic diversity, of spatial structure, rates of cross-fertilization and distance of dispersal of pollen were obtained from these genotypes. The total number of alleles at seven loci evaluated was 125, with an average of 17.8 alleles per locus. For adults the mean allele was 15.8, for the juveniles was 13.5and the seedlings were 11alleles. The average total values of heterozigosidade expected (He) and observed (Ho) were equal to 0.750 and 0.698, respectively. In adults He = 0.750 and Ho =0.714, in juveniles He =0.744 and Ho =0.679 and in seedlings He = 0. 712 and Ho =0. 763. These values indicate that the subpopulation evaluated presents high levels of genetic diversity. The fixation index(f) waspositive and significantforthe generations ofadults(0.052, p <0.05)andjuvenile(0.087, p <0.05), indicating the existence of inbreeding in this subpopulation. The analysis of spatial autocorrelation evidenced that kinship is weakly related to the geographical distance in in bothstagesof lifeevaluated (adults: b= -0.00223, R2 = 0. 000514, p < 0.05 and juveniles: b: - 0.00440, R2 = 0.00148489; p < 0.001).Concomitantly the values of Sp were low and the size of neighborhoods (Nb) were high for the two generations. This result shows that there is no restriction of gene flow via seed and corroborates the hypothesis that the dispersal by animals have high potential to disperse the seeds over long distances.The rates of crossfertilization multilocus (tm= 1.000) and single locus (ts = 0.972 a 1.29) were high and significantly different from zero in all families. The difference in the rate of the crossfertilization multilocus and single locus combined for all families analyzed (tm-ts = 0. 077) was also positive and significant, suggesting that 7% of crossings that occur in this population are between related individuals. The correlation of selfing negative(rs=-0.999), indicates absence of selfing and the correlation of paternity(rp=0.107) not significantly different from zero (SD = 0.135) shows that this subpopulation no full siblings. Every subpopulation resulting outcrossing and individuals are evaluated relatives at least to the 15 level of half-brothers. The paternity analysis assigned pollen donors to 75.2% (64) seedlings, and 24 (37.5%) assignments at a confidence level of 85%, 30 (46.8%) assignments at 95% probability assignments and 10(15.6%) at a confidence level of 99%.This low assignment can be explained by sampling: due to the size of the total area of the population and distribution in aggregate, many individuals may not have been sampled. Moreover, the loci battery used in this analysis could not demonstrated the optimal values for the combined exclusion. Although the maximum distance of pollination has been of 292m and covers the entire area evaluated, most events of pollination (77%) occurred at distances less than 200m. The flowering in mass, the distribution in aggregate and the floral structure are the main responsible for predominance of events of cross-pollination at short distances. / Hancornia speciosa (Apocynaceae) é uma espécie frutífera que apresenta distribuição ampla em áreas de fitofisionomia de Cerrado sentido restrito. Suas flores possuem um mecanismo de polinização complexo e único, adaptado á polinização por mariposas e borboletas. Seus frutos são dispersos por mamíferos de grande e médio porte. Possui alto potencial econômico e sua utilização tem sido realizada de forma exploratória. Para implementar programas de conservação e melhoramento, conhecimentos a cerca da variabilidade genética, da estrutura genética espacial, do sistema reprodutivo e do fluxo gênico nas populações naturais são necessários. Nesse contexto, no presente estudo foi realizada a caracterização molecular da variabilidade genética em três estágios de indivíduos (adultos, juvenis e plântulas) e a avaliação da estrutura genética espacial (adultos e juvenis), do sistema de cruzamento e do fluxo gênico via pólen em uma subpopulação de Hancornia speciosa localizada na região do Parque Estadual da Serra de Jaraguá, Jaraguá-GO. Para tanto, 113 indivíduos adultos e 100 juvenis foram amostrados e georeferenciados em uma área de aproximadamente 2,5 ha. Do total de adultos, 20 árvores matrizes foram selecionadas para obtenção de plântulas e formação das famílias de polinização aberta. O DNA genômico foi obtido a partir das folhas de todos os indivíduos (adultos, juvenis e plântulas) e foi amplificado com o uso de sete locos microssatélites para obtenção dos genótipos. As análises de diversidade genética, de estrutura espacial, taxas de fecundação cruzada e distância de dispersão de pólen foram obtidas a partir desses genótipos. O número total de alelos nos sete locos avaliados foi de 125, com média de 17,8 alelos por loco. Para os indivíduos adultos a média de alelos foi de 15,8, para os juvenis foi de 13,5 e nas plântulas foi de 11 alelos. Os valores totais médios de heterozigosidade esperada (He) e observada (Ho) foram iguais a 0, 750 e 0, 698. Nos adultos He = 0, 750 e Ho =0, 714, nos juvenis He =0, 744 e Ho =0, 679 e nas plântulas He = 0, 712 e Ho =0, 763. Esses valores indicam que a subpopulação avaliada apresenta altos níveis de diversidade genética. O índice de fixação (f) foi positivo e significativo para as gerações de indivíduos adultos (0, 052; p < 0, 05) e juvenis (0, 087; p < 0, 05), indicando a existência de endogamia nessa subpopulação. A análise de autocorrelação espacial evidenciou que o parentesco está fracamente relacionado com a distância geográfica em ambas as gerações de indivíduos avaliadas (adultos: b= -0, 00223, R2 = 0, 000514, p < 0,05 e juvenis: b: - 0, 00440, R2 = 0, 00148489; p < 0, 001). Concomitantemente os valores de Sp foram baixos e o tamanho das vizinhanças (Nb) foram altos para as duas gerações. Esse resultado mostra que não existe restrição ao fluxo gênico via semente e corrobora com a hipótese de que a dispersão por animais tem alto potencial para dispersar as sementes a longas distâncias. As taxas de cruzamento multiloco (tm = 1, 000) e uniloco (ts =0, 972 a 1, 29) foram altas e significativamente diferentes de zero em todas as famílias. A diferença da taxa de fecundação cruzada multiloco e uniloco combinada para todas as famílias analisadas (tm-ts = 0, 077) também foi positiva e significativa, sugerindo que 7% dos cruzamentos que ocorrem nessa população são entre indivíduos aparentados. A correlação de autofecundação negativa (rs = -0,999) indica ausência de autofecundação e a correlação de paternidade (rp= 0,107) não significativamente diferente de zero (SD = 0,135) mostra que 13 nessa subpopulação não existem irmãos completos. Toda a subpopulação é resultante de fecundação cruzada e os indivíduos avaliados são parentes no mínimo ao nível de meiosirmãos. A análise de paternidade atribuiu doadores de pólen para 75,2 % (64) plântulas, sendo 24 (37,5 %) atribuições ao nível de confiança de 85%, 30 (46,8%) atribuições ao nível de 95% de probabilidade e 10 atribuições, 15,6% ao nível de confiança de 99%. Essa baixa atribuição pode ser explicada pela amostragem: devido ao tamanho da área total da população e a distribuição em agregado, muitos indivíduos podem não ter sido amostrados. Além disso, a bateria de locos usada nessa análise não apresentou os valores considerados ótimos de probabilidade de exclusão combinada. Embora a distância máxima de polinização tenha sido de 292m e abrange toda a área avaliada, a maior parte dos eventos de polinização (77%) ocorreu a distâncias inferiores a 200m. A floração em massa, a distribuição em agregado e a estrutura floral são os principais responsáveis pelo predomínio de eventos de polinização cruzada a curtas distâncias.
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Estudos genéticos de jatobá (Hymenaea courbaril L.) em área natural e restauração florestal com espécies nativas / Hymenaea courbaril L. (jatobá): genetic studies in natural population and forest restoration areas with native species

Lya Carolina da Silva Mariano Pereira 09 October 2017 (has links)
O bioma Mata Atlântica tem sofrido com a fragmentação florestal e como forma de reestabelecer ambientes florestais são realizados plantios de restauração. Porém, por muito tempo houve preocupação somente com a composição florística das áreas e a diversidade genética foi negligenciada. Além disso, muitas áreas são implantadas a partir de sementes coletadas em áreas florestais geralmente pouco conservadas, pequenas e isoladas, o que pode comprometer a qualidade genética das mudas, produzindo indivíduos menos adaptados em decorrência da depressão endogâmica. Assim este trabalho teve como objetivo principal analisar o aspecto genético em áreas de restauração na região do Pontal do Paranapanema e área natural de referência, o Parque Estadual Morro do Diabo (PEMD), utilizando o jatobá (Hymenaea courbaril L.) como espécie modelo. No capítulo 1 com o objetivo de verificar a diversidade genética de H. courbaril em áreas de restauração florestal, foram selecionadas duas áreas de plantio com espécies nativas. Nestas áreas e no PEMD foram coletadas amostras foliares de indivíduos adultos que foram genotipadas para oito locos microssatélites. No PEMD ainda foram coletados frutos em 12 matrizes para caracterização do sistema reprodutivo. As três áreas estudadas apresentaram diversidade genética e níveis de endogamia similares. Nas três áreas de estudo foi identificada baixa estruturação genética espacial. Houve predomínio de fecundação cruzada para a produção de frutos na área natural, porém a taxa de cruzamentos entre indivíduos aparentados foi até dez vezes maior que a observada em outras populações da espécie. No capítulo 2 com o objetivo de verificar se há depressão endogâmica em progênies provenientes do PEMD foram selecionadas 320 sementes de 12 matrizes. Estas e seus frutos foram medidos. As plântulas a que deram origem também foram mensuradas, mensalmente, durante 15 meses. Todos os indivíduos foram genotipadas para oito locos microssatélites. A coancestria, foi estimada e os indivíduos separados em: não aparentados (tu), aparentados (tr) e autofecundação (s). Foi verificada diferença entre as métricas das plantas de acordo com o nível de coancestria entre indivíduos. Também foram estimados os valores de depressão endogâmica (ID). A quantidade de indivíduos irmãos de autofecundação foi muito pequena, sendo a maioria proveniente de cruzamento entre indivíduos não aparentados. A depressão endogâmica por autofecundação foi mais evidente no peso e tamanho dos frutos, e amena ou inexistente para os demais caracteres. Isto provavelmente por estas sementes terem sido coletadas em um fragmento grande e bem conservado e que ainda não sofre as consequências da depressão endogâmica. Assim, nosso trabalho mostrou que áreas de restauração florestal que seguiram as recomendações genéticas de implantação, apresentam diversidade genética suficiente para H. courbaril, podendo estas áreas serem fonte de coleta de sementes no futuro. E que os indivíduos provenientes de sementes do PEMD não apresentaram efeito de depressão endogâmica até 15 meses de desenvolvimento em viveiro. / The Brazilian Atlantic Forest was severely deforested and restoration initiatives are necessary to reestablish environments. However, for a long time there is only concern over floristic composition and the genetic diversity has been neglected. In addition, several restoration areas are planted from seeds collected in forest areas that are generally poorly preserved, small and isolated, which may compromise the genetic quality of the seedlings, producing less adapted individuals due to inbreeding depression. The aim of this work was to analyze the genetic aspects of Hymenaea courbaril L. in restoration areas in Pontal do Paranapanema region, and a natural reference forest, the Morro do Diabo State Park (PEMD), where seeds were also collected. In Chapter 1, to verify the genetic diversity of H. courbaril in areas of forest restoration, using eight microsatellites, two restoration areas were selected. In these areas and in the PEMD, leaf samples from adult individuals were collected. In the PEMD, fruits were collected in 12 seed trees for mating system characterization. The three areas presented similar genetic diversity and levels of inbreeding. Low spatial genetic structure was identified in the three studied areas. In the natural forest, fruits were mainly produced through outcrossings, but the rate of mating among relatives was up to ten times higher than the observed in other H. courbaril populations. In Chapter 2, to verify the inbreeding depression in the PEMD were selected 320 seeds from eight seed trees. The seeeds and their fruits were measured. The seedlings were also measured monthly, during 15 months. All seedlings were genotyped with eight microsatellite loci. From the pairwise coancestry the seedlings were separated into three categories: outcrossing among unrelated individuals (tu), outcrossing among related individuals (tr), and selfing (s). We verified differences among groups in the metrics of seedlings according to the level of coancestry among individuals. The values of inbreeding depression (ID) were also estimated. The number of selfed seedlings were very small, and the majority were from outcrossing among unrelated individuals. Inbreeding depression by selfing was more evident in weight and size fruit, and was insignificant or non-existent for other characters. This is probably because these seeds were collected in a large and preserved forest fragment, that does not suffer the consequences of inbreeding depression yet. Thus, our work showed that forest restoration areas that followed the genetic recommendations present enough genetic diversity for H. courbaril, and these areas may be a source of seeds for collection in the future. Besides that, seedlings from seed trees in PEMD did not present inbreeding depression effect up to 15 months of nursery development.
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Modalités fonctionnelles et évolutives des parasitoses développées par les crabes Pinnotheridae aux dépens des échinides fouisseurs

De Bruyn, Colin 14 December 2010 (has links)
Ce travail s’est intéressé aux liens existant entre la stratégie d’exploitation développée par un crustacé ectoparasite et son comportement reproductif. Le crabe Pinnotheridae Dissodactylus primitivus exploite deux espèces Spatangidae vivant dans la Mer des Caraïbes, Meoma ventricosa et Plagiobrissus grandis. Des approches comportementales, démographiques et génétiques ont été adoptées afin de mettre en lumière le fonctionnement et la biologie de cette symbiose. Par son comportement alimentaire, le crabe occasionne des lésions tégumentaires sur ses hôtes. Celles-ci affectent la fitness de M. ventricosa, au travers de son développement gonadique. Dissodactylus primitivus exploite ses deux espèces hôtes de façon asymétrique. La reproduction des parasites se déroule sur les deux hôtes, alors que le recrutement ne s’effectue que sur M. ventricosa. Ce cycle vital asymétrique du crabe serait stabilisé par la qualité et la rareté de P. grandis. En outre, Le comportement sexuel du crabe sur M. ventricosa répondrait aux critères de la polygynandrie à femelles mobiles. Selon ce modèle, les mâles et les femelles se déplacent entre les hôtes à la recherche de partenaires multiples. Lors de ces déplacements, le crabe s’aiderait de son aptitude à localiser chimiquement ses hôtes. Néanmoins, ce mécanisme s’avère plastique et pourrait refléter l’asymétrie du cycle vital. En effet, cette différence n’a pas d’origine génétique, car les crabes vivant au sein du site d’étude constituent la même population quelle que soit l’espèce hôte considérée. Les marqueurs moléculaires microsatellites mis au point dans ce travail permettront lors de futurs travaux d’affiner les observations sur les modalités d’accouplement du crabe et d’estimer sa capacité de dispersion. / This work aimed to highlight the relationships between the host exploitation strategy of an ectoparasite crustacean and its mating system. The pea crab Dissodactylus primitivus exploits two Spatangidae species living in the Caribbean Sea, Meoma ventricosa and Plagiobrissus grandis. Behavioural, demographic and genetic approaches have been conducted to examine the functioning and biology of this symbiosis. Owing to its feeding behaviour, the crab wounds the host tegument. The wounds negatively affect M. ventricosa's fitness through its gonadic development. Dissodactylus primitivus asymmetrically exploits its two host species. The reproduction of the parasites happens on each host, but the recruitment only takes place on M. ventricosa. The asymmetrical life cycle would be stabilised par the quality and the scarcity of P. grandis. The mating system of crabs living on M. ventricosa would correspond to the Pure-search polygynandry of mobile females criteria. According to this model, the males and the females practice the host switching behaviour to find several sexual partners. During these movements, the crab could use its chemodetection ability to locate its hosts. However, this mechanism is plastic and presumably reflects the asymmetrical life cycle of the crab. This difference has indeed not a genetic cause because the crabs living inside the investigated region belong to the same population, whatever the regarded host species. In future studies, the microsatellites markers developed for this work could be used to test the mating system of D. primitivus and to estimate its dispersion ability.
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Sociální chování a akustická komunikace u netopýra velkého (Myotis myotis) / Social behaviour and acoustic communication in greater mouse-eared bat (Myotis myotis)

Porteš, Michal January 2014 (has links)
Order Chiroptera is characterized by great variability in foraging, roost and social strategies. Greater mouse-eared bat (Myotis myotis, Borkhausen 1797) is a model species of a bat in Europe and his seasonal organisation of population represents typical temperate bat cycle with females aggregated in large maternity colonies and solitery roosting males. Although the M.myotis is a model species, the majority of studies were focused on different aspects of maternity colonies biology and the biology of males is still poorly known. Recently founded aggregations of males of M. myotis in highway bridges allow to study social behaviour and acoustic communication of males on between individual level and discuss these findings with known information. While the bridge in Bernartice was inhabited by aggregation of males in individual roosts, in Voznice bridge we found besides males also a maternity colony of M. myotis. Harems of males were established from august until october. We found different pattern of seasonal roost occupancy in males with males with the highest level of mean occupancy having the highest level of female presence in roost. Vocalisation activity of males increased in august with highest level of activity in september. Males roosting closer to the flight entrance tended to have higher...
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Genetic basis and timing of a major mating system shift in Capsella

Bachmann, J.A., Tedder, Andrew, Laenen, B., Fracassetti, M., Désamoré, A., Lafon-Placette, C., Steige, K.A., Callot, C., Marande, W., Neuffer, B., Bergès, H., Köhler, C., Castric, V., Slotte, T. 13 September 2019 (has links)
Yes / A crucial step in the transition from outcrossing to self-fertilization is the loss of genetic self-incompatibility (SI). In the Brassicaceae, SI involves the interaction of female and male speci-ficity components, encoded by the genesSRKandSCRat the self-incompatibility locus (S-lo-cus). Theory predicts thatS-linked mutations, and especially dominant mutations inSCR, arelikely to contribute to loss of SI. However, few studies have investigated the contribution ofdominant mutations to loss of SI in wild plant species. Here, we investigate the genetic basis of loss of SI in the self-fertilizing crucifer speciesCapsella orientalis, by combining genetic mapping, long-read sequencing of completeS-hap-lotypes, gene expression analyses and controlled crosses. We show that loss of SI inC. orientalisoccurred<2.6 Mya and maps as a dominant trait totheS-locus. We identify a fixed frameshift deletion in the male specificity geneSCRand con-firm loss of male SI specificity. We further identify anS-linked small RNA that is predicted tocause dominance of self-compatibility. Our results agree with predictions on the contribution of dominantS-linked mutations toloss of SI, and thus provide new insights into the molecular basis of mating system transitions. / Work at Uppsala Genome Center is funded by 550 RFI / VR and Science for Life Laboratory, Sweden. The SNP&SEQ Platform is supported by 551 the Swedish Research Council and the Knut and Alice Wallenberg Foundation. V.C. 552 acknowledges support by a grant from the European Research Council (NOVEL project, 553 grant #648321). The authors thank the French Ministère de l’Enseignement Supérieur et de la 554 Recherche, the Hauts de France Region and the European Funds for Regional Economical 555 Development for their financial support to this project. This work was supported by a grant 556 from the Swedish Research Council (grant #D0432001) and by a grant from the Science for 557 Life Laboratory, Swedish Biodiversity Program to T.S. The Swedish Biodiversity Program is 558 supported by the Knut and Alice Wallenberg Foundation.

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