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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Faderskapsanalys av tallfrö från Västerhus fröplantage : Skillnaden i pollenkontaminering mellan öppen pollinering och pollinering inom ett avgränsat system

Dahlberg, Helena January 2014 (has links)
In this study, pollen contamination (measured by the number of seeds pollinated by pollen not belonging to any of the clones on the seed orchard) is compared between open pollination and isolated pollination environments in a Scots pine (Pinus sylvestris) seed orchard called Västerhus, located outside Önsköldsvik. In this seed orchard a tent experiment is taking place. Skogforsk has built six large tents covering 12-14 trees with each tent. Fertilization patterns were compared between one tree in a tent with a supplementation of pollen from five clones not represented in the tent and another tree of the same clone subject to open pollination outside the tents. By using DNA markers the paternity was determined for 48 seeds from each tree. The results show a big difference in pollen contamination between the two trees. The tree inside the tent showed a contamination rate of 0% and the tree from the open pollination had a contamination rate of 20,5%. No difference was found in the numbers of different fathers although the selfing rate of 4,26% was higher in the tent than the selfing rate of 2,56% observed in the open pollination environment. These results match the results of other studies done on the same orchard pretty well and therefore tent isolation with a supplementary pollination can be a good way to reduce unwanted pollen contamination.
2

Faderskapsanalys av tallfrö från Västerhus fröplantage : Skillnad i pollenkontaminering mellan öppen pollinering och pollinering inom ett avgränsat system

Dahlberg, Helena January 2014 (has links)
In this study, pollen contamination (measured by the number of seeds pollinated by pollen not belonging to any of the clones on the seed orchard) is compared between open pollination and isolated pollination environments in a Scots pine (Pinus sylvestris) seed orchard called Västerhus, located outside Önsköldsvik. In this seed orchard a tent experiment is taking place. Skogforsk has built six large tents covering 12-14 trees with each tent. Fertilization patterns were compared between one tree in a tent with a supplementation of pollen from five clones not represented in the tent and another tree of the same clone subject to open pollination outside the tents. By using DNA markers the paternity was determined for 48 seeds from each tree. The results show a big difference in pollen contamination between the two trees. The tree inside the tent showed a contamination rate of 0% and the tree from the open pollination had a contamination rate of 20,5%. No difference was found in the numbers of different fathers although the selfing rate of 4,26% was higher in the tent than the selfing rate of 2,56% observed in the open pollination environment. These results match the results of other studies done on the same orchard pretty well and therefore tent isolation with a supplementary pollination can be a good way to reduce unwanted pollen contamination.
3

Acacia saligna as a sustainable agroforestry crop for southern Australia: a genetic assessment.

Millar, Melissa Ann January 2008 (has links)
Acacia saligna is a native species complex with a widespread natural distribution throughout the south west of Western Australia. It is being developed as an agroforestry crop to produce low value, bulk biomass products in the low rainfall agricultural areas of southern Australia. This thesis develops knowledge to assist the domestication and breeding program of A. saligna as an agroforestry cultivar. It also furthers development of a risk management plan for utilisation of the Acacia saligna species complex. Highly informative microsatellite markers for A. saligna were developed for use in mating system studies, paternity analysis and in the development of a diagnostic tool for the identification of individuals and populations at the subspecific level. Microsatellites developed in other Acacia species were also screened for utility in A. saligna. A high level of outcrossing (mean multilocus outcrossing rate of 0.98) and little true selfing was found for a planted stand of A. saligna subspecies saligna. Paternity analysis indicated heterogeneity in pollen clouds experienced by maternal trees and an essentially random pattern of mating within the stand. Inter-subspecific pollen immigration into the stand from trees of subspecies lindleyi was detected for 14% of progeny analysed and occurred over distances greater than 1500 m. Extensive intra-subspecific pollen-mediated gene flow is maintained between remnant natural populations of A. saligna subspecies lindleyi, and a high level of inter-subspecific pollen immigration from trees in the planted stand of A. saligna subspecies saligna was detected in remnant populations of subspecies lindleyi (32% of analysed progeny) occurring over distances greater than 1500 m. Polymorphic microsatellite markers used to investigate genetic structuring within A. saligna revealed a high level of genetic divergence between subspecific entities congruent with a taxonomic reclassification of the species complex. Selected microsatellite markers also proved suitable for use as a rapid diagnostic tool that can be used to characterise populations into one of the proposed subspecies of A. saligna with high probability. These results indicate that high levels of outcrossing and essentially random patterns of mating that maintain genetic diversity in seed crops should be achievable with the suitable management of seed production stands of A. saligna. Appropriate management techniques that limit genetic contamination into seed production stands will need to be employed to achieve this goal. Management techniques will also be required to minimise the risk of genetic contamination from stands planted for agroforestry purposes into remnant natural populations. Isolation distances greater than 1500 m between genetically divergent agroforestry crops and natural populations are suggested in both cases and key areas of further research are suggested. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1336865 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2008
4

Pollination ecology and spatial genetic population structure of wild and cultivated species of cacao (Theobroma) in Bolivia

Chumacero de Schawe, Claudia 18 September 2013 (has links)
Der tropische Regenwald im südwestlichen Amazonasgebiet ist durch den zunehmenden Bevölkerungsdruck, die wirtschaftliche Ausbeutung, die Abholzung und das Abbrennen großer Flächen für die Viehwirtschaft bedroht. Allgemein zeichnen sich tropische Regenwälder durch eine hohe Diversität von Baumarten und daraus folgenden niedrigen Populationsdichten und entsprechend hohen Distanzen zwischen den Artgenossen aus. Die räumliche Verteilung der Individuen hat grundlegende Konsequenzen auf die Bewegung der Bestäuber und den intraspezifischen Genfluss, was somit die sexuelle Fortpflanzung beeinflusst. Daher ist das Wissen über den Genfluss grundlegend für das Verständnis von Reproduktionserfolgen und dem Management tropischer Baumarten. In dieser Studie untersuchte ich unterschiedliche Aspekte der sexuellen Fortpflanzung von wildem und kultiviertem Kakao (Theobroma cacao) und zwei weiteren Theobroma-Arten in Bolivien. Folgende Hypothesen wurden angenommen: 1) Wilde und kultivierte Pflanzen von T. cacao in Bolivien sind genetisch unterschiedlich; 2) Die Verteilungsdistanz der Pollen wilder Kakaopflanzen ist größer als die der kultivierten Pflanzen; 3) Es existiert ein gewisser Genfluss zwischen den wilden und den kultivierten Pflanzen von T. cacao; 4) Die Ansammlung der Bestäuber unterscheidet sich zwischen den Populationen wilder und kultivierter Pflanzen von T. cacao, sowohl in Bezug auf die taxonomische Zusammensetzung als auch in der Abundanz der Blütenbesucher; 5) Die kleinräumige genetische Struktur der Theobroma-Arten ist aufgrund der Abhängigkeit von Tieren bezüglich Bestäubung und Samenverbreitung gemäßigt. Zu diesem Zweck wurden im Tiefland von Bolivien drei verbreitete Arten der Gattung Theobroma ausgewählt: T. cacao L. (wild und kultiviert), T. speciosum Willd. ex Spreng und T. subincanum Mart. Diese Arten sind stammblütige Bäume des Unterwuchses. Sie haben zahlreiche kleine Blüten und schwere Früchte mit essbaren Samen, welche von Fruchtfleisch umgeben sind. Um den Pollenfluss des Kakaos zu untersuchen, schätzte ich den Grad der Selbstbestäubung und die Distanz der Pollenverbreitung sowie den Genfluss zwischen wildem und kultiviertem Kakao. Ich untersuchte zudem, ob sich die wilden von den kultivierten Kakaobäumen genetisch unterscheiden. Um die Kakaobestäuber zu identifizieren, dokumentierte ich die Zusammensetzung der Blütenbesucher auf wildem und kultiviertem Kakao. Weiterhin ermittelte ich die genetische Diversität und die kleinräumige genetische Struktur (SGS) der drei Theobroma-Arten, um die Distanzen der genetischen Verbreitung aus den Mustern der SGS zu schätzen. Die Ergebnisse zeigen, dass wilder und kultivierter Kakao sich genetisch unterscheiden, woraus geschlussfolgert wird,  dass die „wilden“ Populationen des Kakaos im Tiefland Boliviens tatsächlich wilde Formen oder zumindest sehr alte Sorten darstellen. Wilde Populationen zeigten eine geringere genetische Diversität als kultivierter Kakao, was möglicherweise durch die unterschiedliche Herkunft der kultivierten Sorten (z.B. Costa Rica, Trinidad y Tobago) begründet ist. Im Unterschied zu früheren Studien konnte ich Hinweise für die Selbstbestäubung in wildem und kultiviertem Kakao finden, auch wenn die Fremdbestäubung klar dominiert. Selbstbestäubung war häufiger in kultiviertem als im wilden Kakao festzustellen. Die gesamtdurchschnittliche Distanz der Pollenverbreitung betrug 867 m. Die Distanz der Pollenverbreitung des wilden Kakaos lag in einem Bereich von 10 und 3007 m, während die der Pollen des kultivierten Kakaos über Distanzen von 13 bis 2360 m verbreitet wurden. Die Bestäubungsdistanzen des Kakaos waren höher als die der typischen Unterwuchsbaumarten, wenn man die geringen Größen der bestäubenden Mücken berücksichtigt. Der relativ hohe Pollenaustausch von kultiviertem zu wildem Kakao (20%) gefährdet die genetische Identität der wilden Populationen. Weiterhin wurde eine große Auswahl an Blütenbesuchern dokumentiert und erhebliche Unterschiede zwischen den Besuchern des wilden und des kultivierten Kakaos festgestellt. Die Ergebnisse lassen vermuten, dass die Mücken als Haupt- oder gar alleinige Bestäuber in unserem Untersuchungsgebiet nicht in Betracht kommen, da sie zu selten vorkommen. Potenzielle zusätzliche Bestäuber sind die kleine Diptera (z.B. Chloropidae und Phoridae) und Hymenoptera (z.B. Eulophidae und Platygastridae). Die wilden Verwandten des T. cacao, T. speciosum und T. subincanum zeigten eine relativ hohe genetische Diversität. Die Arten von Theobroma hatten eine niedrige, aber signifikant kleinräumige genetische Struktur. T. speciosum zeigte die höchste Distanz der Pollenverbreitung, was auf eine effiziente Samen- und Pollenverbreitung hindeutet, wohingegen T. subincanum die strukturiertere Art mit der geringsten Distanz der Genverbreitung war.  Abschließend sollten bei verbessertem Management der Kakao-Populationen folgende Punkte beachtet werden: Die hohe Distanz der Pollenverbreitung bei Kakao und der relativ hohe Pollenaustausch von kultiviertem zu wildem Kakao zeigt die Notwendigkeit des Schutzes weitläufiger Naturwälder. Um die genetische Identität des wilden Kakaos in Bolivien zu schützen und zusätzlich den genetischen Austausch zwischen den wilden Populationen zu unterstützen, sollte die genetische Variabilität lebensfähiger Populationen zu erhalten werden. Die kleinräumige genetische Struktur in Theobroma macht die Bedeutung des Schutzes der samenverbreitenden Tiere deutlich, um die genetischen Ressourcen dieser tropischen Baumgattung zu erhalten.
5

Efeitos do corte seletivo de árvores sobre o sistema de reprodução e dispersão de pólen em uma população de Hymenaea courbaril na Amazônia brasileira /

Carneiro, Francimary da Silva. January 2010 (has links)
Resumo: Este estudo investigou os efeitos do corte seletivo sobre a diversidade genética, sistema de reprodução e dispersão de pólen em uma população de Hymenaea courbaril L., situado na Floresta Nacional do Tapajós, Estado do Pará, utilizando nove locos microssatélites. A espécie é uma das mais importantes na Amazônia Brasileira devido o alto valor comercial de sua madeira. Antes do corte seletivo, todas as árvores adultas foram mapeadas, amostradas e genotipadas e 367 sementes foram coletadas de 20 árvores matrizes. Após o corte seletivo de 61% das arvores com DAP>81 cm, foram amostradas e genotipadas 250 sementes de 14 árvores reprodutivas. A análise da herança, ligação e desequilíbrio de ligação mostraram que os nove locos utilizados segregam conforme as leis mendelianas, não estão ligados e estão em equilíbrio gamético.As plantas não reprodutivas tinham maior número de alelos (122 alelos) do que as plantas reprodutivas (103) e as progênies (84). Destes alelos, 29 alelos eram exclusivos as plantas não reprodutivas, nove as plantas reprodutivas e 14 as progênies. O número médio de alelos por locos e a heterozigosidade esperada foram significativamente menores nas progênies antes ( k =16,7; Ho =0,710) e após a exploração madeireira ( k =9,33; Ho =0,555). O índice de fixação foi positivo e significativamente diferente de zero em todas as amostras ( F ad=0,111 , F juv=0,160 e F prog=0,045 ), sugerindo endogamia. A estimativa da taxa de cruzamento multilocos populacional ( tm ) foi significativamente menor do que a unidade ( tm =0,962) e a diferença entre a taxa de cruzamento multilocos e unilocos ( tm−t s =0,066) sugere que ocorreram cruzamentos entre parentes. A estimativa do número efetivo de árvores doadoras de pólen antes da exploração ( Nep =3,79) foi significativamente menor que após a exploração de ( Nep =7,2). A taxa de imigração ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study evaluated the effects of selective logging on the genetic diversity, reproductive system and pollen dispersal of a Hymenaea courbaril L. population by using nine microsatellite loci. Because of the characteristics of the wood, this species is one of the most logged in the Amazon resulting in significant reductions in its natural population. The study is located in the Tapajós National Forest, Para State, Brazil, in a 546 ha stand that is part of a governmental initiative for public forest concessions. To determine the effects of logging, both pre- and post-logging populations were analysed. Before logging, all adult trees of H. courbaril were mapped, sampled and genotyped; additionally progeny was analysed based on 367 seeds collected from 20 matrices. After logging took place (61% of the population above 81cm diameter at breast height), 250 seeds from 14 trees were collected and genotyped. Initially, tests for Mendelian inheritance, linkage and gametic disequilibrium were carried out which confirmed no linkage, deviation or disequilibrium for the used loci. The results for genetic diversity showed that the non-reproductive population presented a higher number of alleles (122) than the reproductive population (103) and progenies (84). From all alleles, 29 were exclusive to non-reproductive trees, nine to reproductive and 14 to progeny. The average number of alleles and expected heterozygosity were significantly lower for progenies in both pre- and post-logging situations ( k =16,7; Ho =0,710; k =9,33; Ho =0,555, respectively). The fixation index was positive and significantly different from zero for all sampled populations which suggests endogamy ( F ad=0,111 , F juv=0, 160 e F prog=0,045 ). The multilocus crossing rate was statistically significant ( tm =0,962) and the difference between multilocus and single-locus outcrossing rate was also significant ... (Complete abstract click electronic access below) / Orientador: Alexandre Magno Sebbenn / Coorientador: André Eduardo Biscaia de Lacerda / Banca: Miguel Luiz Menezes Freitas / Banca: Milton Kanashiro / Mestre
6

Estudo hierárquico do sistema de reprodução entre e dentro de frutos, fluxo de pólen e estrutura genética espacial em um fragmento e em árvores isoladas na pastagem de hymenaea stigonocarpa mart. ex hayne na região de cerrado / Hierarchical study of mating system between and within of fruit, pollen flow and spatial genetic structure in a fragment and in trees isolated of hymenaea stigonocarpa mart. ex hayne in the savanna region

Moraes, Marcela Aparecida de [UNESP] 05 February 2016 (has links)
Submitted by MARCELA APARECIDA DE MORAES null (ma_apmoraes@yahoo.com.br) on 2016-03-14T18:12:59Z No. of bitstreams: 1 Tese_MarcelaMoraes_11-03-2016.pdf: 3817894 bytes, checksum: dc95b3a70da2ac90d7bed012881cfc8b (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-03-15T12:31:11Z (GMT) No. of bitstreams: 1 moraes_ma_dr_ilha.pdf: 3817894 bytes, checksum: dc95b3a70da2ac90d7bed012881cfc8b (MD5) / Made available in DSpace on 2016-03-15T12:31:11Z (GMT). No. of bitstreams: 1 moraes_ma_dr_ilha.pdf: 3817894 bytes, checksum: dc95b3a70da2ac90d7bed012881cfc8b (MD5) Previous issue date: 2016-02-05 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Os objetivos deste trabalho foram verificar o sistema de reprodução entre e dentro de frutos, a distância e padrões de fluxo de pólen, os níveis de endogamia e diversidade genética, a depressão por endogamia e a distribuição espacial de genótipos em duas populações de Hymenaea stigonocarpa: a primeira está presente em um fragmento e a segunda em árvores isoladas na pastagem. Para tanto, foram mapeadas e medidas todas as árvores adultas reprodutivas existentes nos dois locais. Foram coletadas sementes de 15 árvores matrizes no fragmento florestal e em 20 árvores matrizes isoladas na pastagem, sendo 30 sementes por árvore. Esta coleta propiciou a instalação de um teste de progênies na Fazenda de Ensino, Pesquisa e Extensão da FEIS/UNESP. Foram feitas a genotipagem de todas as árvores adultas de ambas as populações e de todas as progênies. Adicionalmente, dentro do fragmento foram também amostrados, mapeados e medida a altura de juvenis. As análises genéticas permitiram avaliar os efeitos da depressão por endogamia para altura e sobrevivência, e as análises dos genótipos foram feitas para seis locos microssatélites, já transferidos para a espécie. O estudo do sistema de reprodução foi baseado no modelo misto de reprodução e modelo de cruzamentos correlacionados. A análise de paternidade das sementes permitiu determinar a distância e o padrão de fluxo efetivo de pólen dentro das populações, bem como o fluxo gênico externo das áreas amostradas. A análise da distribuição espacial dos genótipos foi realizada para árvores adultas localizadas dentro dos fragmentos, utilizando-se estimativas do coeficiente de coancestria entre pares de indivíduos dentro de diferentes classes de distância, tornando-se possível estimar o tamanho efetivo de variância e, assim, estabelecer estratégias para a coleta de sementes. Os resultados permitiram entender o processo de reprodução que indica a presença marcante de progênies de irmãos-completos, formação da estrutura genética espacial, vizinhança genética reprodutiva e depressão por endogamia na geração descendente proveniente de ambas as populações de H. stigonocarpa. A coleta de sementes deve ser feita em árvores espaçadas de pelo menos 350 m de distância em 78 árvores com 30 sementes cada árvore para reter o tamanho efetivo de referência de 150 nas amostras para garantir o estabelecimento destas gerações futuras em longo prazo na conservação “ex situ” e/ou reflorestamento em áreas degradadas. / The aim of this work were to study the mating system within and among fruits, distance and pollen flow patterns, inbreeding levels and genetic diversity, inbreeding depression and the spatial distribution of genotypes in two populations of Hymenaea stigonocarpa: first is present in a fragment and the second in isolated trees in the pasture. Therefore, were mapped and measures all existing reproductive adult trees in both sites. It was collected seed of 15 seed trees in the forest fragment and in 20 isolated trees in the pasture, with 30 seeds per tree. This collection allowed the installation of a progeny test in Farm of Teaching, Research and Extension from FEIS/UNESP. It was made genotyping of all adult trees of both populations and all progenies. Additionally, within the fragment were also sampled, mapped and measured the height of juveniles. Genetic analysis allowed to evaluate the effects of inbreeding depression for height and survival, and analysis of genotypes were made for six microsatellite loci, already transferred for the species. The mating system study was based on the mixed mating model and correlated mating model. The paternity analysis of the seeds allowed to determine the distance and the pattern of effective flow of pollen within the fragments, as well as the outside gene flow of the sampled areas. The spatial distribution analysis of genotypes was done for adult trees located within of the fragments, using estimates coancestry coefficient between pairs of individuals within different distances classes, making it possible to estimate the variance effective size and thereby establish strategies for seed collection. The results allowed understanding the process of mating that indicates the strong presence of progeny full-sibs, formation of spatial genetic structure, reproductive genetic neighborhood and inbreeding depression in the descending generation from both populations of H. stigonocarpa. Seed collection should be done in trees spaced of at least 350 m away in 78 trees with 30 seeds each tree to retain the effective size of the reference 150 in the samples to ensure the establishment of these future generations in the long-term conservation "ex situ "and / or reforestation in degraded areas. / CNPq: 141028/2012-2
7

Estudo hierárquico do sistema de reprodução entre e dentro de frutos, fluxo de pólen e estrutura genética espacial em um fragmento e em árvores isoladas na pastagem de hymenaea stigonocarpa mart. ex hayne na região de cerrado /

Moraes, Marcela Aparecida de. January 2016 (has links)
Orientador: Alexandre Magno Sebbenn / Resumo: Os objetivos deste trabalho foram verificar o sistema de reprodução entre e dentro de frutos, a distância e padrões de fluxo de pólen, os níveis de endogamia e diversidade genética, a depressão por endogamia e a distribuição espacial de genótipos em duas populações de Hymenaea stigonocarpa: a primeira está presente em um fragmento e a segunda em árvores isoladas na pastagem. Para tanto, foram mapeadas e medidas todas as árvores adultas reprodutivas existentes nos dois locais. Foram coletadas sementes de 15 árvores matrizes no fragmento florestal e em 20 árvores matrizes isoladas na pastagem, sendo 30 sementes por árvore. Esta coleta propiciou a instalação de um teste de progênies na Fazenda de Ensino, Pesquisa e Extensão da FEIS/UNESP. Foram feitas a genotipagem de todas as árvores adultas de ambas as populações e de todas as progênies. Adicionalmente, dentro do fragmento foram também amostrados, mapeados e medida a altura de juvenis. As análises genéticas permitiram avaliar os efeitos da depressão por endogamia para altura e sobrevivência, e as análises dos genótipos foram feitas para seis locos microssatélites, já transferidos para a espécie. O estudo do sistema de reprodução foi baseado no modelo misto de reprodução e modelo de cruzamentos correlacionados. A análise de paternidade das sementes permitiu determinar a distância e o padrão de fluxo efetivo de pólen dentro das populações, bem como o fluxo gênico externo das áreas amostradas. A análise da distribuição espacial d... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of this work were to study the mating system within and among fruits, distance and pollen flow patterns, inbreeding levels and genetic diversity, inbreeding depression and the spatial distribution of genotypes in two populations of Hymenaea stigonocarpa: first is present in a fragment and the second in isolated trees in the pasture. Therefore, were mapped and measures all existing reproductive adult trees in both sites. It was collected seed of 15 seed trees in the forest fragment and in 20 isolated trees in the pasture, with 30 seeds per tree. This collection allowed the installation of a progeny test in Farm of Teaching, Research and Extension from FEIS/UNESP. It was made genotyping of all adult trees of both populations and all progenies. Additionally, within the fragment were also sampled, mapped and measured the height of juveniles. Genetic analysis allowed to evaluate the effects of inbreeding depression for height and survival, and analysis of genotypes were made for six microsatellite loci, already transferred for the species. The mating system study was based on the mixed mating model and correlated mating model. The paternity analysis of the seeds allowed to determine the distance and the pattern of effective flow of pollen within the fragments, as well as the outside gene flow of the sampled areas. The spatial distribution analysis of genotypes was done for adult trees located within of the fragments, using estimates coancestry coefficient between pairs of ... (Complete abstract click electronic access below) / Doutor
8

Evoluce sociality a rodičovské péče u včel rodu Ceratina / Evolution of sociality and parental care in bees of the genus Ceratina

Mikát, Michael January 2020 (has links)
Small carpenter bees (genus Ceratina) are an excellent model taxon for the study of evolution of parental care and origin of eusociality. Prolonged offspring care is typical for this bee genus. Females usually guard their offspring until adulthood and later feed their adult offspring pollen and nectar. Moreover, most of studied species are facultatively eusocial, a trait probably inherited from the common ancestor of the genus. Although Ceratina bees have generally very interesting behavior, detailed studies were performed in only a few species, usually from North America, Japan and Australia. Only anecdotal observations of natural history existed for a few European species, and detailed research has not been performed before my thesis. The goal of my thesis is to explore the natural history of European species of Ceratina and to identify possible costs and benefits of this species' behavioral traits. I focused on following these behavioral traits: social nesting, guarding of offspring until adulthood, and feeding of mature offspring. Through my master project, I discovered biparental care in species C. nigrolabiata, therefore the most important goal of my Ph.D. project is the evaluation of costs and benefits of this behavior. Guarding of offspring by mother significantly influences their survival,...
9

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
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Self-incompatibility of olive.

Seifi, Esmaeil January 2008 (has links)
The olive (Olea europaea L.) is one of the most ancient fruit trees and has been cultivated for its oil in the Mediterranean area for thousands of years. Today, the consumption of olive oil and table olives is increasing both in traditional producing countries and the entire world. Most olive cultivars are self-incompatible and do not produce a commercial yield after self pollination. In this thesis, inflorescence architecture and sexual compatibility relationships of some olive cultivars, and gene expression in olive pistils during flowering were studied. To study the inflorescence architecture of olive, 45 inflorescences in each of the cultivars Manzanillo, Mission, and Frantoio were checked every morning from flower opening to petal fall. The flower position on the inflorescence had a highly significant effect on the opening day in all cultivars. Terminal flowers and the flowers located on the primary branches opened earlier than flowers located on the secondary branches. Flower position also had a highly significant effect on gender in Manzanillo and Mission. In Manzanillo, the secondary branches had fewer perfect flowers than the primary branches. In Mission, the secondary branches had no perfect flowers at all. In Manzanillo, perfect flowers had significantly longer petal persistence than staminate flowers. To study flower competition within the inflorescence, the distal halves, on which the flowers tend to be perfect, of 120 inflorescences in three trees of Manzanillo were removed about one month before full bloom. This resulted in a highly significant increase in the percentage of perfect flowers on the proximal halves. The effects of shoot orientation and inflorescence location on inflorescence characteristics in the cultivars Frantoio, Kalamata, and Koroneiki were also studied. For each cultivar, inflorescence characteristics in three sections of shoots (top, middle, and base) and four sides of the three selected trees (north, south, east, and west) were recorded. The statistical analysis showed that basal inflorescences were shorter and with fewer flowers but with the same percentage of perfect flowers. Shoot orientation did not have any influence on these characteristics in any of the cultivars. Sexual compatibility was assessed using two methods. In the first method, controlled crossings were performed in the cultivars Frantoio, Koroneiki, and Kalamata. The pistils were harvested one week after hand pollination and stained with 0.1% aniline blue. The styles and ovules were separated, mounted in 80% glycerol, and observed under a fluorescence microscope. In Frantoio and Koroneiki, the number of ovules penetrated by a pollen tube was used to estimate the level of sexual compatibility. In Kalamata, the numbers of ovules penetrated by pollen tubes were not significantly different between treatments; therefore, the number of pollen tubes in the lower style was used. All the cultivars studied were self- incompatible. Frantoio (as a host) was incompatible with Koroneiki and Barnea but partially compatible with Mission. Koroneiki (as a host) was incompatible with Barnea but partially compatible with Frantoio and Mission. Kalamata (as a host) was compatible with Barnea, incompatible with Mission and Koroneiki in 2004, but partially compatible with them in 2005. In the second method, eight microsatellite markers were used for genotyping three Kalamata mother trees, 40 embryos per mother tree, and all the potential pollen donors. Genotyping data were analysed using FaMoz software, and the number of embryos assigned to each putative pollen donor was determined. Paternity analysis showed that Kalamata (as a host) was self-incompatible, compatible with Barnea, Benito, and Katsourela, but incompatible with Arbequina, Azapa, and Picual. To study the gene expression in olive pistils during flowering, a genomic approach was initiated using cDNA subtractive array analysis. Total RNA was isolated from olive pistils at two developmental stages, where self-incompatibility (SI) genes are expected to be differentially expressed: 1) small green flower buds (expression of SI genes not expected) and 2) large white flower buds containing receptive pistils just prior to opening (expression of SI genes expected). From each stage, cDNA libraries were prepared and put through forward and reverse subtractive hybridisations to enrich for differentially expressed cDNAs in stage 2. Macroarrays were prepared by printing 2304 differentially expressed cDNAs onto nylon membranes and hybridised with forwardand reverse-subtracted probes. The analysis identified 90 up-regulated cDNA clones highly expressed in receptive pistils. Further subtracted and unsubtracted hybridisations confirmed up-regulation of the majority of these cDNAs. Gene expression profiles across different tissues showed that most of the genes were pistil-specific. The expression pattern of the genes showed high similarity in Kalamata, Frantoio, Barnea, and Pendolino. All the screened genes were sequenced and their similarities were searched in the NCBI database. The most redundant and interesting up-regulated clones were those similar to a receptor protein kinase-like protein. Some versions of this protein play a role in the sporophytic SI system of Brassica and the gametophytic SI system of Papaver and rye. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1325369 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2008

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