References of "Francis, Frédéric"
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See detailDevelopment of a test to assess the Banana Bunchy Top Virus transmissibility through direct analysis of its aphid vector Pentalonia nigronervosa
De Clerck, Caroline ULg; Francis, Frédéric ULg; Lepoivre, Philippe ULg et al

in Communications in Agricultural and Applied Biological Sciences (2013), 78(1), 49-54

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See detailImpact de substances informatives utilisées pour le contrôle des pucerons de céréales sur la diversité et l’abondance de l’entomofaune non cible
Bayendi-Loudit, Sandrine ULg; Bodson, Bernard ULg; Francis, Frédéric ULg

in Entomologie Faunistique = Faunistic Entomology (2013), 65

Wheat is one of the most cultivated cereals in the world. However, this crop is under attack by many pests and pathogens. In order, to avoid the massive use of the chemicals, other cropping systems ... [more ▼]

Wheat is one of the most cultivated cereals in the world. However, this crop is under attack by many pests and pathogens. In order, to avoid the massive use of the chemicals, other cropping systems semiochemicals can be adopted for a better management of the pests. This study aims to evaluate the use of three semiochemicals ((E)-β-farnesene (EBF), garlic extract and (Z)-3-hexenol) and paraffin on the entomofauna of wheat. This study was conducted at Gembloux Agro-Bio Tech’s experimental farm for nine weeks. Two techniques were used for collecting insects: yellow traps and visual monitoring. The collected insects were sorted, counted and classified taxonomically to the family or species level. This study highlighted the presence of a great diversity of families with EBF treatment and a better proportion of pest and beneficial insects with the smallest quantity of Aphididae. The latter are the most abundant pests on the entire field whatever the considered treatment. The main encountered pests are from Curculionidae, Cecidomyiidae and Chloropidae. Although Chrysomelidae was not high, some damages were observed at the field. [less ▲]

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See detailSymbiont Diversity in Reticulitermes santonensis (Isoptera: Rhinotermitidae): Investigation Strategy Through Proteomics.
Bauwens, Julien ULg; Millet, Catherine ULg; Tarayre, Cédric ULg et al

in Environmental entomology (2013), 42(5), 882-7

The complex microbial community living in the hindgut of lower termites includes prokaryotes, flagellates, yeasts, and filamentous fungi. Many microorganisms are found in the termite gut, but only a few ... [more ▼]

The complex microbial community living in the hindgut of lower termites includes prokaryotes, flagellates, yeasts, and filamentous fungi. Many microorganisms are found in the termite gut, but only a few are thought to be involved in symbiotic association to participate in cellulose digestion. Proteomics provides analyses from both taxonomical and functional perspectives. We aimed to identify symbiont diversity in the gut of Reticulitermes santonensis (Feytaud), via complementary electrospray ionization associated to ion trap tandem mass spectrometry (LC-MS/MS) and two-dimensional gel electrophoresis associated to matrix-assisted laser desorption-ionization-time-of-flight mass spectrometry analysis. One specific challenge to the study of lower termites is the relatively few data available on abundant symbiotic flagellates. Analysis based on LC-MS/MS revealed few protein families showing assignments to eukaryotes and the taxonomic origin of highly represented actins could not be established. Tubulins proved to be the most suitable protein family with which to identify flagellate populations from hindgut samples using LC-MS/MS, compared with other protein families, although this method targeted few prokaryotes in our assay. Similarly, two-dimensional gel electrophoresis associated to matrix-assisted laser desorption-ionization-time-of-flight mass spectrometry did not succeed in identifying flagellate populations, but did permit the identification of most of the prokaryotic components of the symbiotic system. Finally, fungi and yeasts were identified by both methods. Owing to the lack of sequenced genes in flagellates, targeting tubulins for LC-MS/MS could allow fingerprints of flagellate populations to be established. Experimental and technical improvements might increase the efficiency of identification of prokaryotic populations in the near future, based on metaproteomic development. [less ▲]

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See detailComparative analyses of salivary proteins from three aphid species
Vandermoten, Sophie ULg; Harmel, Nicolas; Mazzucchelli, Gabriel ULg et al

in Insect Molecular Biology (2013), under publication

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See detailInfluence of Garlic Intercropping or Active Emitted Volatiles in Releasers on Aphid and Related Beneficial in Wheat Fields in China
Haibo, Zhou; Chen, Julian; Yong, Liu et al

in Journal of Integrative Agriculture (2013), 12(3)

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See detailVariation in the transmission of barley yellow dwarf virus-PAV bydifferent Sitobion avenae clones in China
Yu, Wenjuan; Zhaohuan, Xu; Francis, Frédéric ULg et al

in Journal of Virological Methods (2013), 194

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See detailInfluence of lignin in Reticulitermes santonensis: symbiotic interations investigated through proteomics
Bauwens, Julien ULg; Tarayre, Cédric ULg; Brasseur, Catherine ULg et al

in Symbiosis (2013)

The gut of lower termites is populated by numerous microbial species belonging to prokaryotes, fungi, yeasts and protists. These micro-organisms are organized in a complex symbiotic system, interacting ... [more ▼]

The gut of lower termites is populated by numerous microbial species belonging to prokaryotes, fungi, yeasts and protists. These micro-organisms are organized in a complex symbiotic system, interacting together and with the insect host. Their likely ability to degrade ligno-cellulosic compounds could lead to improvements in second generation biofuels production. Lignin elimination represents a critical point as this polymer significantly interferes with industrial process of cellulose. Although host produces its own lignin-degrading enzymes, some symbionts may participate in digestion of lignin and its degradation products in termite gut. Here, we compared gut proteomes from R. santonensis after rearing on artificial diets composed of cellulose with and without lignin. The effect of lignin in artificial diets on different parts of the digestive tract was compared through liquid chromatography associated with tandem mass spectrometry (LC-MS/MS) experiments. Enzymatic assays were performed to characterize activities present in R. santonensis digestive tract after feeding on artificial diets. Microscopic observations of microbial communities provided some information on population balances after feeding experiment. [less ▲]

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See detailDirect and indirect use of GFP whole cell biosensors for the assessment of bioprocess performances: design of milliliter scale-down bioreactors
Brognaux, Alison ULg; Neubauer, Peter; Twizere, Jean-Claude ULg et al

in Biotechnology Progress (2013), 29(1), 48-59

Substrate limitation responsive biosensors have been used for the development of a mini-bioreactor platform that can be used as a scale-down tool. Three green fluorescent protein (GFP) transcriptional ... [more ▼]

Substrate limitation responsive biosensors have been used for the development of a mini-bioreactor platform that can be used as a scale-down tool. Three green fluorescent protein (GFP) transcriptional reporters have been chosen in Escherichia coli, i.e., uspA::gfp, csiE::gfp and yciG::gfp. Our previous studies have shown that these kinds of promoters are induced in response to substrate limitation and are significantly repressed when cultures are carried out in heterogeneous bioreactors. This sensitivity to substrate limitation has been confirmed in the case of the csiE and yciG biosensors. A mini-scale-down platform is proposed as a high throughput tool to rapidly investigate the usefulness of a given microbial biosensor. This platform is composed of shake flasks able to operate in fed-batch mode either using the slow release or the intermittent feeding principle. Local heterogeneities were reproduced at the level of these mini-bioreactors (operating under the intermittent feeding principle) and caused a decrease in GFP expression as in conventional scale-down reactors. The presence of GFP in supernatants was also noted and seems to be correlated with the substrate limitation signal for the three cultivation systems considered in this work (i.e., chemostat, conventional and mini-bioreactors) and with membrane permeability. [less ▲]

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See detailChemical composition of silage residues sustaining the larval development of the Culicoides obsoletus/Culicoides scoticus species (Diptera: Ceratopogonidae)
Zimmer, Jean-Yves ULg; Saegerman, Claude ULg; Losson, Bertrand ULg et al

in Veterinary Parasitology (2013), 191(1-2), 197-201

Culicoides (Diptera: Ceratopogonidae) are biological vectors of bluetongue virus (BTV). Bluetongue is a viral disease that affects domestic and wild ruminants. Since its recent emergence in northern ... [more ▼]

Culicoides (Diptera: Ceratopogonidae) are biological vectors of bluetongue virus (BTV). Bluetongue is a viral disease that affects domestic and wild ruminants. Since its recent emergence in northern Europe, this disease has caused considerable economic losses to the sheep and cattle industry. The biotopes, and more particularly the chemical characteristics which are suitable for larval development of the main vector species, are still relatively unknown. This study shows that the larvae of biting midges belonging to the species Culicoides obsoletus and Culicoides scoticus are able to breed in different types of silage residue (maize, grass, sugar beet pulp and their combinations). The chemical composition of substrates strongly influences the presence of the immature stages of these biting midges. Higher lignin and insoluble fibre contents seem to favour their presence and could play the role of a physical support for semi-aquatic larvae. In contrast, higher concentrations of magnesium and calcium are negatively correlated with the presence of these two species. These data will help to locate and monitor the breeding sites of these species and could contribute to the control of these insects on farms. [less ▲]

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See detailUtilisation des termites comme source de microorganismes dans la filière de production du bioéthanol de seconde génération
Tarayre, Cédric ULg; Bauwens, Julien ULg; Brasseur, Catherine ULg et al

Poster (2012, November 14)

Les termites abritent une microflore symbiotique qui intervient dans la dégradation des fibres constitutives du bois, synthétisant des enzymes capables d’hydrolyser ses composants. Les sucres ... [more ▼]

Les termites abritent une microflore symbiotique qui intervient dans la dégradation des fibres constitutives du bois, synthétisant des enzymes capables d’hydrolyser ses composants. Les sucres fermentescibles libérés suite à cette hydrolyse sont utilisables dans le cadre de la production du bioéthanol de seconde génération. [less ▲]

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See detailDiversité de l’abeille & sélection de souches tolérantes à Varroa destructor
Leclercq, Gil ULg; Francis, Frédéric ULg; Haubruge, Eric ULg et al

Conference given outside the academic context (2012)

Présentation des 2 volets de recherche du projet "Selapis" (D31-1280) : la diversité de l'abeille et la sélection de souches tolérantes au Varroa

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See detailDiversity and breeding sites of mosquitoes (Diptera, Culicidae) potentially vectors of arboviruses in Belgian equestrian farms
Boukraa, Slimane ULg; De la Grandière de Noronha Cotta, Maria Ana ULg; Bawin, Thomas ULg et al

Poster (2012, October 08)

This study aims to determine the potential importance of the livestock farms, especially equestrian, to welcome and favor the proliferation of certain species of mosquito responsible for transmission of ... [more ▼]

This study aims to determine the potential importance of the livestock farms, especially equestrian, to welcome and favor the proliferation of certain species of mosquito responsible for transmission of arboviruses. The study of biodiversity of Culicidae in the horse farms in Belgium is carried out on species sampled at 64 biotopes in six stations study. Five surveys were realized during 2011 (June, July, August and October) and one in 2012 (June). The morphotaxonomic and molecular study of mosquitoes collected showed the presence of ten species: Culisata annulata Schrank, 1776; Anopheles claviger s.s. Meigen, 1804; An. maculipennis s.s. Meigen, 1818; An. messae Falleroni, 1926; Culex pipiens molestus Forskal, 1775; Cx. pipiens pipiens Linné, 1758; Cx. torrentium Martini, 1925; Cx. hortensis hortensis Ficalbi, 1889; Cx. territans Walker, 1856 and Coquillettidia richardii Ficalbi, 1889. Among the 24893 individuals examined in 2011, Cx. pipiens sl and Cx. torrentium represent 68.00% and 22.38% respectively of total harvest. These last species with Cs. annulata, are dominants and ubiquitous in all the horse farms visited. The species of the genus Anopheles have strong ecological requirements and are therefore associated with some special habitats; other species however have a strong ability to adapt and therefore attend a wide variety of biotopes (Cx. pipiens, Cx. torrentium and Cs. annulata). At the horse farms, water troughs and ponds are the most favorable habitats for larval development of Culicidae. The species potentially vectors of arboviruses that can cause problems in epidemiological equestrian farms are Cx. pipiens sl, Cx. torrentium and Cs. annulata. [less ▲]

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See detailLaboratory and field preliminary tests of Metarhizium anisopliae formulated with neem oil (Suneem) against Anopheles gambiae sl adult emergence
Seye, Fawrou; NDIONE, Raymond; Touré, Mamour et al

Poster (2012, October 08)

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See detailLaboratory and field preliminary tests of Metarhizium anisopliae formulated with neem oil (Suneem) against Anopheles gambiae sl adult emergence
Seye, Fawrou; Ndione, Raymond; Touré, Mamour et al

Poster (2012, October 08)

Metarhizium anisopliae have shown great potential for the control of malaria vectors. However, their ability to control aquatic stages of anopheline vectors with conidial formulation is need. In ... [more ▼]

Metarhizium anisopliae have shown great potential for the control of malaria vectors. However, their ability to control aquatic stages of anopheline vectors with conidial formulation is need. In laboratory condition (25°C and 76%RH), we formulated M. anisopliae with emulsifian neem oil (Suneem 1%) before application on An. gambiae larvae at 4, 6, 8, 10 and 12 % (v/v) to determine the LD90. We applied in semi-field environment, the LD90 of the formulation into artificial vats on the Anopheles gambiae sl larvae collected from many breeding sites at dry and rain seasons. In laboratory condition, the LD 50 was 4.4 x 10^6 spores/ml and the LD90 was not obtained 24 after exposure. The probite line equation was Y=1.61 x – 0.55 and R²= 0.9793. The LD 50 was 3.1 x 10^6 and the LD90 was 5.3 X 10^6 spores/ml 48 h after exposure. The probite line equation was then Y= 1.69 x + 1.79 and R²= 0.9757. Microscope magnifying revealed also the fungal attack via cuticle and mycelia germination one dead larvae and pupae. In semi-field environment, treatment revealed that, at 5.3 x 10^6 spores/ml, the formulation has a great emergence inhibition of mosquito adult formation. No significant difference was observed between dry and rain season application of M. anisopliae on the larvae. Therefore, a combination of M. anisopliae with Suneem may provide a more sustainable management strategy for malaria vectors control at the larval stages. [less ▲]

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See detailStudy of the virulence of african horse sickness virus serotypeS 4 and 9 in two mouse models
De la Grandière de Noronha Cotta, Maria Ana ULg; Francis, Frédéric ULg; Caij, Ann Brigitte et al

Poster (2012, September)

Objectives African horse sickness is an infectious disease caused by a double stranded positive RNA virus which belongs to the family Reoviridae, genus Orbivirus. The virus has nine known antigenically ... [more ▼]

Objectives African horse sickness is an infectious disease caused by a double stranded positive RNA virus which belongs to the family Reoviridae, genus Orbivirus. The virus has nine known antigenically distinct serotypes and is transmitted by a culicoides biting midge, principally Culicoides imicola. African horse sickness causes severe morbidity and mortality up to 95 % in horses with severe economic losses. The establishment of an experimental mouse model is needed for the investigation of the pathogenesis of this infection. Methods Two mouse models, interferon-α receptor knock-out mice and immunocompetent mice, were tested. The used virus for mice inoculations belonged to the two serotypes which caused epidemics in Europe, serotypes 4 and 9. The virus was inoculated by subcutaneous route and/or by intra-nasal route. Samples of whole blood were taken for each infected and knock-out mice at regular intervals. The organs (liver, spleen, kidney, lung and brain) were taken at the end of experience of when the most affected mices were euthanasied. All these samples were tested by a qRT-PCR targeting African horse sickness genome segment 7. Results The results demonstrate the potential of the immunodeficient mouse model for both clinical and biological features. Both serotypes of African horse sickness were detected by qRT-PCR until three weeks post-infection (corresponding with the end of the experience) in blood. Conclusions The setting up of this mouse model has developed a tool for efficient in vivo study to characterize the in vivo virulence of this virus, to monitor the evolution of viral populations during in vivo replication cycles and to test the competence or vectorial capacity of indigenous Culicoides. Acknowledgement Research supported by the Belgium Federal Public Service, Health, Food Chain Safety and Environment. [less ▲]

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