Dissertations / Theses on the topic 'Arthropodes'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Arthropodes.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
François, Sarah. "Diversité et écologie des virus associés aux arthropodes : des communautés aux génomes." Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTT106/document.
Full textHigh throughput sequencing technologies have revealed the extraordinary diversity of viral sequences in hitherto largely unexplored host groups. Thus, our knowledge about arthropod viruses, infecting the most diverse and abundant animals on Earth, was hitherto essentially reduced to species of economical and medical interest. New data on viral diversity in arthropods illustrate the need to expand viral inventory at the scale of the ecosystem and to include viruses as an essential component of their functioning and their evolution.In my thesis, I developed and applied two approaches to study the diversity of viruses in arthropods and how virus circulate in ecosystems, focusing on species of agronomic interest: (i) a virus-centered approach by exploring nucleotidic sequence databases, searching for the presence of a group of small DNA viruses infecting arthropods, the densoviruses (ii) an arthropod-centered approach at the scale of the ecosystem, using a viral metagenomic method to analyze viral communities associated with arthropods from different trophic levels from the same agroecosystems.My results showed that:(i) Densoviruses are spread throughout the animal kingdom - particularly in a wide diversity of arthropods - and are highly diverse genetically, which led to a better understanding of the evolutionary history of this group of viruses;(ii) A number of new viruses can be described in pests: the spider mite (Tetranychus urticae, Acari) from laboratory populations, as well as the green pea aphid (Acyrthosiphon pisum, Hemiptera), the alfalfa weevil (Hypera postica, Coleoptera) and the cotton bollworm (Helicoverpa armigera, Lepidoptera) from natural populations sampled from alfalfa crops and grasslands. These studies also highlighted that specific viromes are associated with each pest species, and I characterized the distribution of some of these viruses in arthropod communities. In total, more than 60 new species of arthropod and plant viruses were discovered. Their evolutionary links with known virus species was characterized by phylogenetic analyzes.(iii) The work realized in (ii) also contributed to optimize a methodology to prepare and analyze viromes from multiplexed samples, that is particularly suitable to optimize the taxonomic allocation of sequences and thus reduce the "dark matter" that is inherent to viral metagenomics analyses
Marty, Christian. "Arthropodes venimeux en Guyane française." Nice, 1988. http://www.theses.fr/1988NICE6047.
Full textEl, Hamzaoui Basma. "Identification des arthropodes et pathogènes associés par MALDI-TOF MS et étude des relations entre arthropodes et bactéries." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0696.
Full textThis work focuses on three main parts, a first part presents an epidemiological study of bacteria associated with soft ticks in Algeria, or we identified morphologically and confirmed by molecular biology six species of Argasidae. In addition, looking further we could detect Borrelia hispanica in Ornithodoros occidentalis and Borrelia cf turicatae in Carios Carpensis. On the other hand, in Argas persicus a new genotype of Bartonella spp has been identified as well as a new species of Anaplasmatacea bacteria.A second part evaluates the vectorial capacity of bed bugs to transmit Borrelia recurrentis, the agent of the relapsing fever. For this reason an experimental model of artificial infection of Cimex lectularius by Borrelia recurrentis has been developed, to study the presence of bacteria in feces. In this model, four approaches were used: qPCR, fece’s culture, FDA (Fluorescein Diacetate) and fece’s inoculation to mice. Immunofluorescence was also used to detect the location of the bacteria in the body of the bed bug. We confirmed that bed bugs acquire the bacteria and excrete live microorganisms in the feces. They can be considered as potential vector of Borrelia recurrentis.The third part is an assessment of the capacity of MALDI-TOF MS to identified fleas, bed bugs and associated pathogens. This innovative tool, which has revolutionized medical entomology and has shown its efficiency to identify several species of arthropods, has also been able to distinguish between infected and uninfected fleas and bugs, and even distinguish between fleas and bugs infected by the same species of bacteria
Nebbak, Amira. "Développement expérimental et application sur terrain d'outils innovants pour l'identification des arthropodes." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0605.
Full textHematophagous arthropods such as mosquitoes, ticks, and fleas are of significant importance in public health because of their ability to transmit major diseases to humans and animals. Vector control and epidemiological vector surveillance are essential in the strategy of combating vector-borne diseases. The latter is successful only by a correct and precise identification of the vectors. Thus in this work, we have developed and improved the protocols of samples preparation for the identification of adult mosquitoes and their aquatic stages, ticks, and fleas by MALDI-TOF MS. This tool has been already distinguished as being reliable for the arthropods identification. The second part of our work consisted in the application of these protocols on mosquito larvae collected in the field during an entomological investigation carried out in the city of Marseille. In this study, the relevance and reliability of MALDI-TOF MS for the identification of mosquito larvae collected in the field were verified. Finally, we carried out the inventory of the viral communities of three mosquito species collected in Marseille by metagenomics, which revealed the presence of numerous new viruses. All the results presented in this thesis emphasize that the use of innovative tools such as MALDI-TOF MS and metagenomics to study vectors and the agents they carry is a promising strategy that will contribute to the knowledge of zoonotic transmission cycles and the potential risks of the emergence of vector-borne diseases in human populations
Gambart, Thomas Alliot Anne. "Les arthropodes vecteurs de maladies infectieuses chez l'Homme." [S.l.] : [s.n.], 2005. http://theses.univ-nantes.fr/thesemed/PHgambart.pdf.
Full textGauthier, Maxime. "Implication de l’acide rétinoïque dans la reproduction et le développement et perturbations par des pesticides chez le gammare (Gammarus fossarum) et l’abeille domestique (Apis mellifera)." Electronic Thesis or Diss., Lyon 1, 2023. http://www.theses.fr/2023LYO10072.
Full textThe presence of pesticides in both terrestrial and aquatic ecosystem compartments is of significant concern for non-target wildlife species. The use of biomarkers allows an effective biomonitoring and points out early imbalances in these organisms. Retinoids (RETs, vitamin A and their derivatives) are essential compounds for vertebrates and are used as biomarkers to assess the chemical pressure in ecosystems. Several studies suggested the involvement of retinoic acid (RA, active form of vitamin A) in the development and reproduction of arthropods. In order to establish the potential of RETs in view of biomarkers development, we studied two arthropods, the gammarid Gammarus fossarum (crustacean) and the honey bee Apis mellifera (insect). The obectives orour study was to 1) identify and measure the RETs of these models, 2) study the involvement of AR in reproduction and development, and 3) evaluate the effects of pesticides on the RETs and on these two functions in G. fossarum and A. mellifera. A new analytical method (UHPLC-MS/MS) allowed the observation of a decrease in the RET precursors retinaldehyde (RALD) and retinol (ROL) during the reproduction of G. fossarum and the development of A. mellifera, respectively, as wel as an increase in RA metabolites. The upward and downward fluctuations in RA concentrations affected the growth of bees and the oogenesis, embryogenesis and molting of gammarids following exposure to AR and citral (CIT, a RA synthesis inhibitor) suggesting endogenous functions of RA in these arthropods. Exposure to MET altered the RA isomers ratio in G. fossarum which may be associated with the observed effects on oogenesis and molting. Exposures to MET and GLY induced disturbances in the bee’s RETs (larvae, pupae, and adults), but only MET interfered with its development. The results suggest an involvement of RA in the reproduction and molting of G. fossarum and in the development of A. mellifera. Here, we demonstrate that the RETs system of these models is influenced by the presence of pesticides. These results open a research avenue for RET-based biomarkers in arthropods
Gers, Charles. "Écologie et biologie des arthropodes terrestres du milieu souterrain superficiel : fonctionnement et écologie évolutive." Toulouse 3, 1992. http://www.theses.fr/1992TOU30097.
Full textFraj-Lagha, Mehdia. "Biodiversité des arthropodes dans les agroécosystèmes. Application à l'échelle de la basse vallée Majerda en Tunisie." Thesis, Poitiers, 2013. http://www.theses.fr/2013POIT2266/document.
Full textIn Tunisia, few studies on the macrofauna and species diversity of terrestrial isopods in the agroecosystems were performed. To fill this gap, the spatio-tempral (plots, sectors and season) diversity of macrofauna and Oniscidea was analysed. We studied the distribution of Isopods in Majerda agroecosystems related to cultivation types (orchards, market gardening, vegetable crops), irrigations systems (sprinkler, surface and drip) and soil physico-chemical characteristics. Sampling was carried out with pitfalls traps during in 15 plots during 2008-2009 and 11 plots during 2009-2010. Nineteen groups of macrofauna was found. Coleoptera, Oniscidea, Hymenoptera, Diptera, Othoptera and Aranea were the most present and abundant. Isopods were abundant in autum in the vegetable crops cultivation. In the coastal plots (Ghar El Melh sector) diversity was higher than in the terrestrial plots (Utique sector). Nine species of terrestrial isopods belonging to 6 genera were identified. Porcellio laevis was the most frequent species in all seasons. According to cultivation types, the number of individuals and the species richness were important in vegetable crops and barely cultivation. The spatial distribution of Oniscidea showed that isopods were abundant in the plots of Pont of Bizerte irrigated by sprinkler systems and wastewater. Year factor affected the diversity of fauna and isopods. Oniscidea species distribution was correlated to conductivity, texture and the content of Mg2+ Ca2+ and K+ of soil
Dieme, Constentin. "Etude des relations entre arthropodes et rickettsia felis." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM5042/document.
Full textVector control is one of the most important aspects of medical entomology and requires accurate identification of vectors. Within the past decade, the MALDI-TOF MS technique has proven its potential as a fast and effective tool for identification of adult blood-sucking arthropods. From then on we were interested in the development of an identification protocol of aquatic stages of mosquitoes by MALDI-TOF MS. On the other hand, the detection of a pathogen in an arthropod does not necessarily mean its ability to transmit. Incrimination of an arthropod as vector follows certain rules ranging from suspicion to demonstrate its vector competence in the laboratory. To better understand the epidemiology of R. felis we first participated in an investigation conducted in Reunion, testing fleas, the only biological vectors known to date. We demonstrated the potential role of the mosquito particularly Anopheles gambiae, in the transmission of R. felis. Finally, we used the MALDI-TOF MS for the determination of the Anopheles gambiae infection status to R. felis. We also offer a probable transmission cycle of R. felis to man including psocids and mosquitoes
Veeraragoo, Nyanapragassen. "Les repulsifs : indications, formulations, utilisations." Université Louis Pasteur (Strasbourg) (1971-2008), 1994. http://www.theses.fr/1994STR1M049.
Full textLecq, Stéphane. "Importance de la structure des haies, des lisières, et de la disponibilité en abris sur la biodiversité, implications en termes de gestion." Phd thesis, Université de Poitiers, 2013. http://tel.archives-ouvertes.fr/tel-00938190.
Full textSantorufo, Lucia. "Effects of land use transformation on microarthropod community structure in Mediterranean area." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0086/document.
Full textThe effects of human-mediated activities on soil quality and functioning have been assessed. Composition and changes in arthropod community structure and laboratory bioassays were performed on urban soils in order to understand the roles of metal contamination on soil organism activities and distribution. Then, comparison of urban, agricultural, industrial and forest soils were performed, monitoring Collembola species and functional traits composition, in order to assess if the impact of urban environment is greater than other kinds of anthropization. Soil organism community was analysed twice a years for evaluating the role of seasonality on anthropic impacted soils. The different kinds of anthropization firstly affected the abiotic properties of the sites. Agricultural and urban soils were the most impacted soils by human activities, which cause changes in vegetation cover, organic matter amounts and accumulation of hazardous elements and compounds. Soils organisms responded to soil abiotic modifications. In particular, in urban environment soil organisms were strongly reduced at high level of metal contamination, whereas organic matter content and climatic conditions played the main role at low-intermediate soil contamination. Collembola community showed a strong reduction in species richness in agricultural soils, with a consequent domination of few tolerant species. Collembola functional trait distribution was mainly affected by the presence and the type of litter and inputs of contaminants. In particular, agricultural environment favoured organisms with traits adapted to soil life surface, whereas forest soils favoured organisms with euedaphic characteristics. Industrial and urban soils showed organisms with both epiedaphic and euedaphic characteristics
Jeanson, Raphaël. "Dynamique d'agrégation et prises de décisions collectives chez les arthropodes." Toulouse 3, 2003. http://www.theses.fr/2003TOU30069.
Full textDiarra, Zan Adama. "Développement et utilisation d’outils innovants en entomologie médicale." Thesis, Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0523.
Full textBlood-sucking arthropods ensure the active biological transmission of many pathogens from one animal to another, including humans. Vector control and epidemiological surveillance of vectors are essential for the control and monitoring of vector-borne diseases.The correct identification of arthropods, the determination of the origin of the blood meal and the associated pathogens are crucial steps in vector control. Our work thus focused on a combination of methods (morphology, molecular and MALDI-TOF MS) for the identification, determination of blood meals and pathogens associated with hosts and their arthropods. The first part of our work was to use the MALDI-TOF MS tool to identify ticks collected in Mali and stored in 70% ethanol. Ticks were also tested by molecular biology to look for microorganisms. We also identified by MALDI-TOF MS mosquitoes collected in Chad and preserved with silicagel. The animal origin of the blood meal of these mosquitoes could also be studied by this tool. The second part allowed us to detect microorganisms in domestic and wild animals and their ectoparasites in Algeria and Mali through molecular biology. Our work therefore enabled us to confirm the interest of MALDI-TOF MS in medical entomology, with for the first time its application on mosquitoes collected in the field in the south and preserved with siligalel, and to complete the directory of pathogens associated with arthropods in Mali and Algeria
Rousset, François. "Les facteurs determinant la distribution des wolbachia, bacteries endosymbiotiques des arthropodes." Paris 11, 1993. http://www.theses.fr/1993PA112006.
Full textDobson, C. M. "Insecticides from sprayers and the effect on beneficial arthropodes in winter wheat." Thesis, Imperial College London, 1986. http://hdl.handle.net/10044/1/37994.
Full textBaldaia, Luis. "Role des ecdysteroides dans les processus de differenciation tegumentaire chez les arthropodes." Paris 6, 1988. http://www.theses.fr/1988PA066037.
Full textLeulmi, Hamza. "Etude des relations entre arthropodes et bactéries : épidémiologie moléculaire et modèles expérimentaux." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM5020/document.
Full textThis work focuses on three areas; the first is a contribution to the study of the repertoire of bacteria associated with arthropod vectors (tick and flea) in North Africa (Algeria) and in Sub-Saharan Africa (Benin, Tanzania and the Democratic Republic of Congo). We could thus detected by molecular tools (qPCRs, standard PCR and sequencing) and for the first time in Benin, Rickettsia typhi (the agent of murine typhus) and Bartonella sp in fleas collected from rodents in Cotonou. In this work, we have also associated the agent of plague (Yersinia pestis), and for the first time in fleas of DR of Congo, and we detected also R. felis (the causative agent of spotted fever). In Tanzania, we have highlighted the presence of R. typhi and R. felis fleas on rodents. In Algeria, we described for the first time the presence of Lyme disease agent (Borrelia garinii) in hard ticks. We confirmed the presence of R. massiliae, R. monacensis, R. aeschlimannii, R. slovaca and R. felis, we also detected for the first time Bartonella tamiae and Coxiella burnetii associated with bat ticks in Algeria.Regarding the second part we was interested in the evaluation of vector competence of cat fleas (Ctenocephalides felis) and bed bugs (Cimex lectularius) in the transmission of trench fever agent (Bartonella quintana) that is known to be transmitted by lice. Three approaches have been tested; qPCR, culture and immunohistochemistry
Mahari, Saâdia. "Etude synécologique des niveaux de peuplement arthropodien de l'écosystème chêne-liège dans les suberaies de la Mamora et de Ben Slimane (Maroc)." Aix-Marseille 3, 1992. http://www.theses.fr/1992AIX3A004.
Full textGuilbert, Éric, and Simon Tillier. "Biodiversite des arthropodes de la canopee dans deux forets primaires en nouvelle-caledonie." Paris, Muséum national d'histoire naturelle, 1994. http://www.theses.fr/1994MNHN0015.
Full textGARCIA, MACHADO ERIK. "Genome mitochondrial de la crevette penaeus notialis. Reflexion sur la phylogenie des arthropodes." Paris 11, 1997. http://www.theses.fr/1997PA112015.
Full textGARCIA, MARIA. "Recherches sur l'origine, metabolisme et fonction des ecdysteroides chez les invertebres non-arthropodes." Paris 6, 1991. http://www.theses.fr/1991PA066495.
Full textYssouf, Amina. "Identification des arthropodes vecteurs et des micro-organismes associés par MALDI-TOF-MS." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM5031/document.
Full textArthropods are vectors bloodsucking and can ensure the active biological transmission of a pathogen responsible of human or veterinary diseases. The vector control and vectors epidemiological surveillance are essential in the strategy against the vectors-borne diseases. Accurate, reliable and rapid identification of vectors and associated pathogens are essential. Thus, in this project we evaluated the use of MALDI-TOF MS for the arthropods vectors identification as well as for the detection of associated pathogens. This proteomics technology emerged since few years ago and is currently used in routine for bacteria identification in many microbiology laboratories. In the first part of our work, we used the MALDI TOF to identify the tick, mosquito and flea species. For each arthropod, we determined which part allowed obtaining reproducible spectra by MALDI TOF and correct identification by blind test, after reference database creation. The second part consisted to use the MALDI-TOF MS to detect the associated Rickettsia in ticks including Rickettsia conorii and R. slovaca, two human pathogens transmitted by Rhipicephalus sanguineus and respectively Dermacentors marginatus. The spectral variations were obtained between infected and non infected specimens with specific masses related to the tick infection by Rickettsia. The identification technique of not or infected ticks was validated by blind tests. The obtained results allowed concluding that the MALDI-TOF MS could be used in the future to identify the ticks removed from patient, the arthropods vectors and during entomological survey and determine the prevalence of infection of these arthropods
Lebrun, Bruno. "Etude de toxines alcaloi͏̈diquesd'arthropodes : étude physico-chimique et toxicologique du venin des myriapodes du genre Glomeris et analyse électrophysiologique du mécanisme d'action d'un dérivé synthétique d'alcaloi͏̈des présents dans le venin des fourmis du genre Monomorium." Aix-Marseille 1, 1994. http://www.theses.fr/1994AIX11081.
Full textObame-Nkoghe, Judicaël. "Caractérisation de l'entomofaune hématophage cavernicole du Gabon et implication dans la transmission d'agents infectieux." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT159/document.
Full textThe man's ecological mark on natural forest environments of central Africa has been increasing in recent decades, and only few natural areas remain non exploited yet. Thus, even supposedly hostile environments such as caves meet the primary needs of surrounding populations (hunting, fishing, shamanic practices), or economical needs (mining and ecotourism). That anthropization is likely to increase the exposure of human populations to multiple infectious agents carried by cave fauna. The presence of wild or domestic animals in the surroundings of caves also increase that risk. Among these infectious agents, some can be transmitted by direct contact with animal reservoirs, whereas others may require the involvement of blood-sucking insects. The role of these insects in the epidemiology of many pathogens is well known in Africa, particularly in epigeic environments, but remains largely investigated in caves. In this thesis work, we proposed to address that issue. In six caves of Gabon we firstly explored the diversity of blood-sucking Diptera, and we studied temporal dynamics of species assemblages. Secondly, we undertook a molecular screening of haemosporidia, bacteria and viruses using nested PCR and high-throughput sequencing.The work carried out has enable to make a taxonomic inventory of the Diptera fauna of the investigated caves. Our study revealed a significant diversity of the blood-sucking Diptera fauna, accounting for more than 60 percent of blood-sucking Diptera species currently known in Gabon, in all types of areas. Our data showed that the composition of Diptera communities was different from one cave to another, and that Diptera assemblages varied over time according to micro-climate fluctuations within caves. The screening of infectious agents in Diptera collected helped 1) to explore the parasitic, viral and bacterial diversity they host, and 2) to assess their involvement in transmission
Baringou, Stéphane. "Diversité et fonctionnalité de « nouveaux types » de Heat Shock Protein-70 kDa chez les arthropodes." Thesis, Le Mans, 2016. http://www.theses.fr/2016LEMA1009/document.
Full textThe 70 kDa Heat Shock Proteins (HSP70) are considered the most conserved members of the HSP family. These molecular chaperones are primordial to living beings, because of their implications in many cellular pathways and the management of multiple environmental stress factors (e. g., temperature, pollutants, salinity, radiations). Widely used in ecology as a biomarker of environmental stress, the HSP70 family is also a privileged therapeutic target for neurodegenerative diseases and cancers. In the cytosol, a wide variety of HSP70 is observed in few model species (Drosophila, human, yeast). Nevertheless, the diversity of cytosolic HSP70 remains unclear amongst the Arthropoda phylum, especially within decapods. The diversity studies of cytosolic HSP70 were based on 735 sequences from 198 arthropod species, including 142 sequences from decapods obtained during this work. Molecular phylogeny analyses revealed at least three distinct groups of HSP70 within arthropods, comprising several unrecognised subdivisions. This study proposes a new classification and an evolutionary model of cytosolic HSP70 amongst the Arthropoda phylum. The expression profiles observed in each group lead to reconsider the HSP70 classification according to their constitutive (HSC70) or inducible (HSP70) features. The observed structural specificities of genes and proteins, relative to each form of HSP70, will probably have to be linked to distinct interactions with cochaperones or other co-factors
Kumsa, Bersissa. "Molecular investigation of arthropods and vector-borne bacteria from Ethiopia." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM5054/document.
Full textOur study to explore bacteria in ixodid ticks collected from domestic animals in Ethiopia revealed an overall prevalence of 6% (46/767) SFG rickettsiae, 3.8% (29/767) Borrelia DNA and 6.4% (54/842) C. burnetii in different tick species. The study to investigate bacteria in 303 fleas collected from domestic dogs and cats in Ethiopia that were morphologically identified as Ctenocephalides felis felis, Ctenocephalides canis, Pulex irritans and Echidnophaga gallinacean showed Rickettsia felis in 21% of fleas, mainly in Ctenocephalides felis, with a similar prevalence in fleas from dogs and cats. The study to investigate bacteria in lice and sheep ked (Melophagus ovinus) revealed Acinetobacter spp. in M. ovinus, Heterodoxus spiniger, Bovicola ovis and Linognathus vituli. Partial rpoB gene sequence revealed A. soli, A. lowffii, A. pitti and 3 new Acinetobacter spp. in the lice and keds. Molecular identification of lice using an 18S rRNA gene analysis confirmed the morphological methods of lice identification. Bartonella melophagi was identified by standard PCR followed by sequencing of fragments of the gltA and rpoB genes in M. ovinus.Overall, our findings alert physicians managing patients with fever of unknown aetiology in Ethiopia and those who care for travellers from Ethiopia to consider the presence of several vector-borne zoonotic species of bacteria including SFG rickettsiae, C. burnetii, R. felis, B. henselae and B. melophagi as potential causative agents
Pichon, S. "Système de sécrétion de type IV et protéines à domaines ankyrines dans les interactions Wolbachia-arthropodes." Phd thesis, Université de Poitiers, 2009. http://tel.archives-ouvertes.fr/tel-00551985.
Full textPichon, Samuel. "Système de sécrétion de type IV et protéines à domaines ankyrines dans les interactions Wolbachia-arthropodes." Poitiers, 2009. http://theses.edel.univ-poitiers.fr/theses/2009/Pichon-Samuel/2009-Pichon-Samuel-These.pdf.
Full textWolbachia are intracellular Gram(-) bacteria that are reproductive manipulators of many arthropods. In the isopod Armadillidium vulgare, the Wolbachia wVulC strain induces male feminization. Here, we characterized two vir operons which are expressed in all host tissues and which encode a type IV secretion system (T4SS) used to translocate bacterial effectors into host cytoplasm. Gene organization and sequence comparison in 37 Wolbachia strains highlighted the high conservation of both vir operons and their importance for the biology of the bacteria. We also identified in the on-going assembly of the wVulC genome, 66 ankyrin domain-encoding genes. Ankyrin motifs are known to mediate protein-protein interactions in eukaryotic organisms and thus are suggested to mediate in Wolbachia the interaction with host molecules. We showed that one of the three copies of the wVulC pk2 gene is only expressed in feminizing strains but not in the three strains inducing cytoplasmic incompatibility in terrestrial isopods. The associated Pk2 protein could be involved in male feminization. We thus tested the interaction between three T4SS proteins and five ankyrins (including Pk2) via the yeast twohybrid and CRAfT (Cre-recombinase Reporter Assay for Translocation) methods. None of the five ankyrin proteins were revealed to be secreted by the wVulC strain. Nevertheless, this promising approach may enable us to identify Wolbachia effectors
Vila, Bruno. "Influence d'un grand mammifère phytophage sur la dynamique forestière. Etude dendroécologique des conséquences actuelles et passées de l'introduction du cerf à queue noire sur la végétation ligneuse de l'archipel de Haida Gwaii (Canada)." Aix-Marseille 3, 2002. http://www.theses.fr/2002AIX30072.
Full textThe aim of this study is to identify and assess the consequences of browsing by a large mammal on forest vegetation in order to understand how a large herbivore can modify forest dynamics. Using the introduction of black-tailed deer to Haida Gwaii islands (Canada), the dendrochronological approach combined with chemical analyses show that there is (1) a cessation in shrub recruitment; (2) an alteration in tree species recruitment ruled by physical defences in spruce and hemlock and (3) a selection of individuals better capable of chemical defence in western red cedar. Historical approach shows that although deer colonisation was rapid across the archipelago, spatial and temporal differences do occur. They are linked to isolation, human pressure, habitat characteristics and climate. Disproportionate changes between species triggered by deer over several decades have resulted in substantial changes in forest dynamics
Montagné, Nicolas. "Evolution moléculaire d'une famille de neuropeptides au sein des arthropodes : l'exemple de la CHH (Crustacean Hyperglycemic Hormone)." Paris 6, 2008. http://www.theses.fr/2008PA066488.
Full textKabakibi, Mhd Maher. "Les communautés des arthropodes frondicoles sur chêne liège et sur chêne vert dans le massif des Maures (Var) : composition, structure, évolution spatio-temporelle." Aix-Marseille 3, 1989. http://www.theses.fr/1989AIX3A002.
Full textLewis, Graham Allan. "Development of a protocol for sampling arthropod diversity in areas of native vegetation /." Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09ACH/09achl674.pdf.
Full textRocher, Léo. "Identification des paramètres de la végétation favorisant les arthropodes bénéfiques et les fonctions écologiques associées en viticulture : approche corrélative et expérimentale." Electronic Thesis or Diss., Avignon, 2024. http://www.theses.fr/2024AVIG0375.
Full textBiodiversity decline within agroecosystems is mainly attributed to modern agriculture. The main causes include the destruction of semi-natural structures, the increase in field size and the high use of agrochemicals for fertilisation and pest control. Arthropods contribute significantly to the key ecosystem services such as pest control and pollination. They largely depend on the vegetation within fields and in the surroundings. Plants provide food resources and other habitat functions that are crucial for the survival and reproduction of arthropods. Semi-natural structures are important to maintain species-rich vegetation, and thus arthropods with associated ecological functions. In permanent crops such as vineyards, semi-natural structures can be established in inter-rows within fields. However, in the French Mediterranean, inter-rows are often tilled to remove non-crop vegetation since winegrowers are afraid of water competition and the spread of undesirable weeds. This thesis aims to better understand how inter-row vegetation promotes beneficial arthropods and predation of pest insects while limiting the spread of undesirable plant species in Mediterranean vineyards of South-Eastern France (Luberon). The present thesis addresses three major research questions: (1) Do inter-row vegetation cover and its floristic composition affect ant species and diversity, that were found to be vineyard predators? (2) Which functional groups of the vegetation are related to the abundance of predators, parasitoids, pollinators and predation sentinel prey? (3) Does species-richinter-row vegetation increase the abundance of such beneficial arthropods, improve predation of sentinel prey and limit the spread of undesirable plant species? In the first chapter, we studied the ant response to inter-row vegetation in 23 vineyards. We tested the effects of three types of inter-row vegetation management on ant diversity and frequency: fully, partially, and non-vegetated vineyards. We showed that partially vegetated vineyards had greater ant species richness compared to non-vegetated ones. Grass and perennial plant cover positively influenced ant species richness, demonstrating the importance of inter-row vegetation and itsmanagement. In the second chapter, we examined which characteristics of spontaneous vegetation affect beneficial arthropods and sentinel prey predation in 37 vineyards. We found that nectariferous flower cover and plant species richness favoured most groups of beneficial arthropods, as well as predation. These results underline the importance of floral resources and plant diversity in promotingthe studied beneficial arthropods. The last chapter focuses on a sowing experiment that was analysed for two years. Three types of inter-row vegetation were compared: high diversity sowing, spontaneous vegetation, and inter-rows without vegetation. In agreement with the second chapter, our results highlight the positive effects of plant species richness and flower cover on weed control, beneficial arthropod abundance, and predation of sentinel prey. The overall results of the different studies conducted in this thesis converge and highlight the importance of considering vegetation characteristics to promote beneficial arthropods in vineyard ecosystems
Fischer, Luc. "Étude comparée de l'incidence de trois insecticides : deltamethrine, dimethoate, phosalone sur la faune des arthropodes épiges des Agrosystèmes céréaliers : cas d'un traitement à la floraison en culture de blé d'hiver." Paris 11, 1987. http://www.theses.fr/1987PA112047.
Full textFischer, Luc. "Etude comparée de l'incidence de trois insecticides, delthaméthrine, diméthoate, phosalone sur la faune des arthropodes épiges des agrosystèmes céréaliers." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37605090c.
Full textMarty, Patrick. "Rapports entre Eucalyptus camaldulensis et E. gomphocephala, leurs arthropodes corticoles, Phoracantha semipunctata et le milieu dans deux arboretums marocains." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37615906b.
Full textDassou, Anicet. "Effet de la diversité des cultures sur les réseaux trophiques des arthropodes et la régulation du charançon du bananier par des prédateurs généralistes dans les systèmes pluri-spécifiques à base de plantain." Thesis, Montpellier, SupAgro, 2014. http://www.theses.fr/2014NSAM0043/document.
Full textFunctional diversity and associated biodiversity in agroecosystems provide and promote important services to human society such as pollination, biological control, and nutrient cycling. Intercropping is a practical way to increase plant diversity in agroecosystems and participates to provide alternative foods and to structure arthropod communities, including generalist predators involved in pest control. To better understand how plant diversity structures the arthropod food web and how the control of pest may be optimized, we first made one meta-analysis to understand the mechanisms linking plant diversity to pest control by generalist predators at local scale. We second studied the effect of plant diversity on the arthropod community in contrasted plantain fields. We showed that predator abundance was positively correlated with plant diversity while herbivore abundance was negatively correlated with plant diversity. This strong and inverse effect of plant diversity on herbivore and predator abundance suggests that top-down forces structure the arthropod community in plantain fields and that it should be possible to structure the predator community to better control herbivores including pests. In a third step, we measured the effect of combinations of three associated crops maize Zea mays, cocoyam Xanthosoma sagittifolium and gourd Lagenaria siceraria as intercrops on ant community structure and then the effect relation between ant abundances with Cosmopolites sordidus damages. The three associated plants had a significant effect on abundance of all ant species but in different magnitudes and with either negative or positive effect showing that the selection of plant species that are intercropped is an efficient way to structure the ant community. The abundances of all species of ants were positively or negatively correlated with the damages of C. sordidus larvae. The abundances of Camponotus spp., Monomorium spp., Paratrechina longicornis and Tetramorium sp. were negatively correlated to C. sordidus damage. These ants appear to be the best candidates for C. sordidus control. These findings will help in the design of plantain agroecosystems that enhance pest control services.Keywords: Plant diversity, intercropping, arthropod food webs, ants, interspecific interactions, habitat structure
Fagan, William Fredric. "Population dynamics, movement patterns, and community impacts of omnivorous arthropods /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/5270.
Full textBernard, Alexandre. "De l'activité individuelle à la coopération auto-organisée chez les arthropodes : exemple de la construction d'une toile chez les araignées." Nancy 1, 2002. http://docnum.univ-lorraine.fr/public/SCD_T_2002_0232_BERNARD.pdf.
Full textCariou, Marie. "Développement et utilisation de marqueurs RADseq pour l'étude de l'impact de Wolbachia sur l'évolution des génomes mitochondriaux chez les Arthropodes." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10092/document.
Full textThe spread of endosymbiotic bacteria can drive that of the linked mitochondrial genomes within the cytoplasm. This hitchhiking selection can lead to a reduction of the effective population size of the mitochondrial genomes (Ne). 1t can also facilitate mitochondrial introgression, following the introduction of exogenous mitochondria in a species by hybridization. The main objective of my thesis is to quantify these different effects, on a global scale, using a large sample of Arthropods. Mitochondrial introgressions can lead to discrepancies between the evolutionary histories of mitochondrial and nuclear genomes. To investigate such patterns, we used RADseq genomic markers, that allow reconstructing population histories, and developed improvements for the library preparation and data analysis. Using in silico experiments, 1 showed that RADseq data is suitable for phylogenetic inferences (Cariou et al. 2013). Adjustments in the RADseq protocol also allowed us to demonstrate the applicability of this method for highly multiplexed libraries (Henri et al. 2015). The impact of various biases related the estimation of population genetic diversity using RADseq was also investigated in silico, which lead me to propose an ABC method to correct some of them. Following these developments, 1 showed on 30 species of Diptera and Lepidoptera that nuclear markers always confirmed the mitochondrial genetic relatedness, ruling out the hypothesis of recent mitochondrial introgressions. On a larger sample, we detected a reduction of the mitochondrial Ne in Wolbachia infected lineages. This reduction caused a significant decrease in the polymorphism of infected populations, but appeared insufficient to reduce the efficacy of natural selection
Fang, Rong. "Production and application of monoclonal antibodies : immunological detection of Rickettsiae from their associated arthropod vectors." Aix-Marseille 2, 2003. http://www.theses.fr/2003AIX20681.
Full textHafidi, Najat. "Relation entre l'hétérogénéité de la structure des litières et le peuplement de macroarthropodes édaphiques en forêt tempérée." Paris 11, 1989. http://www.theses.fr/1989PA112127.
Full textVakanas, Guillaume. "Les mécanismes de la coopération chez les Arthropodes sociaux : étude de la prédation chez une araignée sociale "Anelosimus eximius" ("Araneae,Theridiidae)." Nancy 1, 2002. http://www.theses.fr/2002NAN10025.
Full textPredation in a social species of spider, Anelosimus eximius, is characterised by 3 steps: during the first spiders are recruited, thus it capture and finally transport the prey. The organisation observed during capture and transport is explained by a coordination of individual acts that results of an adjustment of their behaviours to the state of the prey and to its environment (stimergic process). This is confirmed by computer simulation. The regulation of the number of individuals participating in every stage of the predation is also explained by auto-organisation phenomena. It is the prey features (vibrations, weight and size) that regulate the individual involvement. The nutritional status of individuals is also involved in this regulation. Small spiders are more active than large one. Thus, cooperation during predation emerges from group living and doesn't require sophisticated communication mechanisms between individuals. It permits to understand better how the passage from solitary to social species has been realised without important modifications of individual behaviours
Franc, Serge. "Savoirs, affectivité et comportements : articulation de trois dimensions pour comprendre comment se construisent les apprentissages dans le contexte de l'éducation à la biodiversité : le cas de l'étude d'arthropodes à l'école primaire en France." Phd thesis, Université Montpellier II - Sciences et Techniques du Languedoc, 2012. http://tel.archives-ouvertes.fr/tel-00743867.
Full textDoherty, Jean-François. "Phénologie et modèles prévisionnels d'éclosion printanière pour trois arthropodes ravageurs en plantation commerciale d'arbres de Noël dans un contexte de changements climatiques." Master's thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/27826.
Full textThe balsam twig aphid Mindarus abietinus and the spruce spider mite Oligonychus ununguis are two pests of economic importance for the Christmas tree industry in Québec. Current climate change could affect their biology and physiology in such a way that, if their local densities in commercial fir plantations grow in the future, potential damage to cultivated firs could increase substantially. In order to study the interactions between M. abietinus, its host tree, and ambient temperature, I followed populations of the aphid during three consecutive summers in commercial fir plantations of southern Québec. I found it possible to separate overlapping generations of different morphs of this aphid in growing colonies on fir shoots, which allowed to record a proportion of wingless daughters several times larger than previously known for this aphid in its complex life cycle. Based on a field experiment, a warmer environment surrounding the aphids on balsam fir shoots increased spring colony growth rates significantly, when compared to unaltered colonies on neighbouring trees. These results support the hypothesis that a warmer climate, caused by anthropogenic change, would promote higher densities of M. abietinus on fir shoots, which could increase esthetic damage to Christmas trees. In a laboratory experiment, I studied the effect of ambient temperature on postdiapause development of the overwintering eggs of both aphid and mite species, along with that of another conifer-feeding pest, the pine needle scale Chionaspis pinifoliae, which led to parametrise new linear and nonlinear development rate models for postdiapause egg development of all three species. Finally, by following fresh mass of M. abietinus overwintering eggs throughout their diapause of several months, it was possible to observe a substantial increase in size and mass of these eggs in early spring, suggesting that water could trigger diapause termination and/or initiate embryogenesis of the first active stage.
Kreher, Felix. "Molecular and functional analysis of the auxiliary proteins generated from the M segment of Rift Valley fever virus : Impact of proteins P14/NSm and P78/NSm-GN on virus propagation in the mammalian and arthropod hosts." Paris 7, 2013. http://www.theses.fr/2013PA077260.
Full textRift Valley fever virus (RVFV) is an arbovirus endemic in Africa, which has an economic and; public health impact by affecting ruminants and humans. The viral genome is divided into three segments, L, M and S, in negative or ambisense polarity. The M segment encodes the two major structural glycoproteins, GN and Gc, and at least two additional proteins, P78/NSm-GN and P14/NSm which are non-essential for virus growth in vitro. We identified an additional 13 kDa protein, referred to as NSm', which corresponds to a N-terminally truncated form of P14/NSm. We further assessed the role of the NSm-related proteins on 1 RVFV propagation by comparing mutant viruses expressing various sets of the NSm related proteins to a rescued wild-type virus in experimentally infected mice and mosquitoes. Only the lack of P14/NSm and P13/NSm' proteins affected virulence drastically in the mouse model, identifying these proteins as the major virulence factor encoded by the M segment. These observations correlated with reduced growth of a P14/NSm and P13/NSm' KO mutant in murine macrophages. Additionally, P78/NSm-GN appeared as a major determinant of virus dissemination in infected mosquitoes and a mutant virus lacking P78/NSm-GN was found to show altered virus production during acute and persistent infection of mosquito cells. This study demonstrates the differential contribution of the NSm- related proteins to virus propagation in mammalian and arthropod hosts, the NSm/NSm' protes being essential for viral virulence in mice and the P78/NSm-GN glycoprotein conditioning virus spread in the mosquito vector
Lhéritier, Mickaël. "Une fenêtre évolutive sur la terrestrialisation des arthropodes : étude des Myriapodes du gisement à préservation exceptionnelle de Montceau-les-Mines (Carbonifère, 305 Ma)." Electronic Thesis or Diss., Lyon 1, 2024. http://www.theses.fr/2024LYO10224.
Full textTerrestrialisation (colonisation of terrestrial environments) is a major step in the history of life. It goes along an explosion of biological diversity in continental environment (land and aerial environment), and reshape the superficial envelopes of Earth. In the animal kingdom, arthropods are one of the main actors of this ecological revolution (ex : insects, arachnids) that begins surely since the Ordovician (485-444 Ma) and increases during the Carboniferous (359-299 Ma). Another main part of this arthropod fauna, the myriapods (millipedes and centipedes), seems to colonise land early and play a crucial role in initial development of soils and nutriments cycle, leading the way to new floral and faunal colonisations. The exceptionnally preserved locality of Montceau-les-Mines (Saône-et-Loire; Carboniferous ~ 305 Ma) yields a rich and diversified flora and fauna preserved in 3D in nodules and offer an evolutive window on terrestriaisation. This PhD goal is to study the three groups of myriapods present in Montceau-les-Mines: the diplopods ("millipedes"), the arthropleurids and the euthycarcinoids to reconstruct with accuracy their morphology, their life mode, their adaptations to continental life, their role in continental ecosystem as well as their phylogenetic relationships (with extant representatives)
Azarbayjani, Fathollah Fathi, of Western Sydney Hawkesbury University, Faculty of Science and Technology, and School of Science. "Assessment of estimators and factors affecting arboreal arthropod biodiversity on Melaleuca Linariifolia." THESIS_FST_SS_Azarbayjani_F.xml, 1997. http://handle.uws.edu.au:8081/1959.7/246.
Full textDoctor of Philosophy (PhD)
Kabakibi, Mhd Maher. "Les Communautés des arthropodes frondicoles sur chêne liège et sur chêne vert dans le massif des Maures (Var) composition, structure et évolution spatio-temporelle /." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37614601j.
Full text