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See detailDiversity and ecology survey of mosquitoes potential vectors in Belgian equestrian farms: A threat prevention of mosquito-borne equine arboviruses
Boukraa, Slimane ULg; de la Grandière, Maria Ana ULg; Bawin, Thomas ULg et al

in Preventive Veterinary Medicine (2016), 124

Emergence of West Nile Virus was recently recorded in several European countries, which can lead to severe health problems in horse populations. Europe is also at risk of introduction of mosquito-borne ... [more ▼]

Emergence of West Nile Virus was recently recorded in several European countries, which can lead to severe health problems in horse populations. Europe is also at risk of introduction of mosquito-borne equine alphavirus from Americas. Prevention of these arboviruses requires a clear understanding of transmission cycles, especially their vectors. To characterize mosquito fauna, their ecology and identify potential vectors of equine arboviruses in Belgium, entomological surveys of six equestrian farms located in the Wolloon Region were conducted during 2011–2012. The harvest of mosquitoes was based on larval sampling (272 samples from 111 breeding sites) and monthly adults trapping (CO2-baited traps, Mosquito Magnet Liberty Plus). Among 51,493 larvae and 319 adult mosquitoes collected, morphological identification showed the presence of 11 species: Anopheles claviger (Meigen), An. maculipennis s.l. (Meigen), An. plumbeus (Stephens), Culex hortensis (Ficalbi), Cx. territans (Walker), Cx. pipiens s.l. L., Cx. torrentium (Martini), Coquillettidia richiardii (Ficalbi), Culiseta annulata (Schrank), Aedes cantans (Meigen), Ae. geniculatus (Olivier). Molecular identification of Cx. pipiens species complex allowed the detection of three molecular forms, Pipiens (92.3%), Molestus (4.6%) and Hybrid (3.1%). Larvae of Cx. pipiens sl and Cx. torrentium were omnipresent and the most abundant species. Water troughs, ponds and slurry (liquid manure) were the most favorable breeding sites of mosquito larvae. Based upon behavior and ecology of the identified mosquito species, Studied Belgian equestrian farms seem to provide a suitable environment and breeding sites for the proliferation of potential vectors of arboviruses and those being a real nuisance problem for horses and neighboring inhabitants. [less ▲]

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See detailTowards sustainable food systems: the concept of agroecology and how it questions current research practices. A review
Hatt, Séverin ULg; Artru, Sidonie ULg; Brédart, David ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment (2016), 20(Special issue 1), 215-224

Introduction. Multiple environmental and socio-economic indicators show that our current agriculture and the organization of the food system need to be revised. Agroecology has been proposed as a ... [more ▼]

Introduction. Multiple environmental and socio-economic indicators show that our current agriculture and the organization of the food system need to be revised. Agroecology has been proposed as a promising concept for achieving greater sustainability. This paper offers an overview and discussion of the concept based on existing literature and case studies, and explores the way it questions our current research approaches and education paradigms. Literature. In order to improve the sustainability of agriculture, the use of external and chemical inputs needs to be minimized. Agroecological farming practices seek to optimize ecological processes, thus minimizing the need for external inputs by providing an array of ecosystem services. Implementing such practices challenges the current structure of the food system, which has been criticized for its lack of social relevance and economic viability. An agroecological approach includes all stakeholders, from field to fork, in the discussion, design and development of future food systems. This inclusion of various disciplines and stakeholders raises issues about scientists and their research practices, as well as about the education of the next generation of scientists. Conclusions. Agroecology is based on the concept that agricultural practices and food systems cannot be dissociated because they belong to the same natural and socio-economic context. Clearly, agroecology is not a silver-bullet, but its principles can serve as avenues for rethinking the current approaches towards achieving greater sustainability. Adapting research approaches in line with indicators that promote inter- and transdisciplinary research is essential if progress is to be made. [less ▲]

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See detailConsumer acceptance of insect-based alternative meat products in Western countries
Caparros Megido, Rudy ULg; Gierts, Chloé; Blecker, Christophe ULg et al

in Food Quality & Preference (2016)

During the past few years, entomophagy has been increasing in significance. As insects are generally high in protein, they are principally considered as meat substitutes. Nevertheless, in Western ... [more ▼]

During the past few years, entomophagy has been increasing in significance. As insects are generally high in protein, they are principally considered as meat substitutes. Nevertheless, in Western countries, meat substitute consumption is actually very low, principally due to food neophobia and poor sensory qualities in comparison with meat. In insect particular case, food neophobia is clearly high. To reduce insect food neophobia, previous studies suggest to insert invisible insect in food preparation and/or to associate them with known flavors. In this study, a survey on entomophagy perception and hedonic tests were realized to assess the level of sensory-liking of hybrid insect-based burgers (beef, lentils, mealworms and beef, mealworms and lentils). Participants’ overall liking of the four burgers differed between genders and was influenced by burger appearance and taste. Women clearly preferred beef burger appearance, whereas men preferred the appearance of beef and insect-based burgers. Concerning insect-based burger taste, participants (men and women) rated it intermediately, between that of the beef and lentil burger, with a preference for the mealworm and beef burger. Results also showed that people with previous entomophagy experience was limited but that they gave globally higher ratings to all preparations. In conclusion, insect tasting sessions are important to decrease food neophobia, as they encourage people to “take the first step” and become acquainted with entomophagy. Nevertheless, insect integration into Western food culture will involve a transitional phase with minced or powdered insects incorporated into ready-to-eat preparations, as people are not ready to add insects to their diets in “whole form.” [less ▲]

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See detailOptimization of a cheap and residential small-scale production of edible crickets with local by-products as an alternative protein-rich human food source in Ratanakiri Province (Cambodia)
Caparros Megido, Rudy ULg; Alabi, Taofic ULg; Nieus, Clément et al

in Journal of the Science of Food and Agriculture (2016)

Background - Health status of the indigenous people of the Ratanakiri Province, Cambodia, is significantly lower compared to the rest of the nation. The domestication and mass production of insects may ... [more ▼]

Background - Health status of the indigenous people of the Ratanakiri Province, Cambodia, is significantly lower compared to the rest of the nation. The domestication and mass production of insects may represent a sustainable, cost effective and high quality alternative source of protein to traditional livestock. This study aimed to optimise a cheap and residential cricket breeding system based on unused wild resources. The cricket development, Teleogryllus testaceus (Walker), under seven diets composed of taro aerial parts, young cassava leaves, young cashew leaves and brown rice flour (with or without banana slices), versus a traditionally used broiler feed diet was studied. Results - Cricket mortality was low in all diets, except the two cashew-based diets. Total biomass was significantly higher under the broiler feed, in addition to the two diets containing a combination of cassava leaf powder and brown rice. Yet, crickets fed with the taro diet had the highest percentage of protein. Concerning the breeding system cost, units using cassava leaves were the cheapest ones. Conclusion – Diets based of cassava leaves seems to be the most promising ones. Nevertheless, to produce crickets with a high body mass and a high protein level, a new experiment must be realised in which the cassava leaf maturity will be adapted to fit with the cricket growth stage. Moreover, to reduce the cost of the breeding units, handmade local products should be used instead of purchased components. [less ▲]

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See detailPreliminary report of mosquitoes survey at Tonga Lake (North-East Algeria)
Amara Korba, Raouf; Boukraa, Slimane ULg; Alayat, Moufdia Saoucen et al

in Advances in Environmental Biology (2016), 9(27), 288-294

Background: Mosquitoes are transmitters of several human diseases including, malaria, filariasis, West Nile virus and Rift Valley fever virus. To planified and succeful any mosquito vector control, a good ... [more ▼]

Background: Mosquitoes are transmitters of several human diseases including, malaria, filariasis, West Nile virus and Rift Valley fever virus. To planified and succeful any mosquito vector control, a good understanding of the occurrence of specific important vector species, their abundance and distribution are needed. Objectives: The present study aimed to identify the mosquito potential vectors distributed throughout Tonga Lake region, a part of National Park of El-Kala situated in northeastern Algeria and to discuss the epidemiological importance of these insects. Results: Thirteen species representing five genera were identified: Ae. brelandi, Ae. vexans, An. plumbeus, An. labranchiae, Cx. pipiens s. l., Cx. perexiguus, Cx. theileri, Cx. pusillus, Cx. modestus, Cx. impudicus, Cs. longiareolata, Cs. annulata, Ur. unguiculata. The dominant species was Cx. pipiens s. l. with more than 70%. Conclusion: The occurrence of Aedes, Anopheles and Culex is suggestive of the presence of a risk for vector-borne diseases such as malaria, West Nile fever, Rift Valley Fever and filariasis in the area. In this study, results on species diversity may help in the future planning of vector control measures. [less ▲]

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See detailMolecular detection of six (endo-) symbiotic bacteria in Belgian mosquitoes: first step towards the selection of appropriate paratransgenesis candidates
Raharimalala, Fara Nantenaina; Boukraa, Slimane ULg; Bawin, Thomas ULg et al

in Parasitology Research (2016)

Actually, the use of symbiotic bacteria is one of alternative solution to avoid vector resistance to pesticides. In Belgium, among 31 identified mosquito species, 10 were considered as potential vectors ... [more ▼]

Actually, the use of symbiotic bacteria is one of alternative solution to avoid vector resistance to pesticides. In Belgium, among 31 identified mosquito species, 10 were considered as potential vectors. Given to introduction risks of arbovirosis, the purpose of this study was to investigate the presence of symbiosis bacteria in potential mosquito vectors. Eleven species caught from 12 sites in Belgium were used: Culex pipiens s.l., Culex torrentium, Culex hortensis, Anopheles claviger, Anopheles maculipennis s.l., Anopheles plumbeus, Culiseta annulata, Ochlerotatus geniculatus, Ochlerotatus dorsalis, Aedes albopictus, and Coquillettidia richiardii. Six genera of symbiotic bacteria were screened: Wolbachia sp., Comamonas sp, Delftia sp., Pseudomonas sp., Acinetobacter sp., and Asaia sp.Atotal of 173 mosquito individuals (144 larvae and 29 adults) were used for the polymerase chain reaction screening. Wolbachia was not found in any Anopheles species nor Cx. torrentium. A total absence of Comamonas and Delftia was observed in all species. Acinetobacter, Pseudomonas, and Asaia were found in most of species with a high prevalence for Pseudomonas. These results were discussed to develop potential strategy and exploit the variable occurrence of symbiotic bacteria to focus on them to propose biological ways of mosquito control. [less ▲]

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See detailImpact of climatic factors on the release of E-β-caryophyllene from alginate beads
Daems, Frédéric ULg; Bera, François ULg; Lorge, Stéphanie ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2016), 20(2),

Description of the subject. Alginate beads that release semiochemical compounds are interesting biological control devices used to attract the natural enemies of aphids in infested crops. Little ... [more ▼]

Description of the subject. Alginate beads that release semiochemical compounds are interesting biological control devices used to attract the natural enemies of aphids in infested crops. Little information, however, is available about the impact of climatic factors on the release of semiochemicals from this diffusive system. Objectives. The objective of this scoping study was to investigate the impact of temperature, relative humidity and wind speed, on the release of E-β-caryophyllene from alginate beads. Method. The impact of the three climatic factors on the release of E-β-caryophyllene from alginate beads was evaluated using a Box-Behnken experimental design and a laboratory scale volatile collection system. The influence of relative humidity on bead water content and size, with and without this semiochemical, was also investigated using a gravimetric method and an easy-to-use photographic device, respectively. Results. The results showed that an increase in temperature caused a significant increase in the E-β¬-caryophyllene release rate. Neither relative humidity nor airflow, however, had a significant effect on the release of this semiochemical when relative humidity and wind speed ranged from 33% to 75% and from 6.61 x10-4 m.s-1 to 2.05 x10-2 m.s-1, respectively. The isotherm curves obtained were characteristic of food products and biopolymer materials. The isotherm shapes were not modified by the incorporation of the semiochemical into alginate beads, and showed an important increase in water content when relative humidity values exceeded 85%. Fortunately, this water content increase did not affect bead size, which facilitates the calculation of E-β-caryophyllene release. Conclusion. The present study shows for the first time the impact of the three main climatic factors on the release of E-β-caryophyllene from alginate beads. It allows learning more about how these biological control devices operate in order to optimize future field trials. [less ▲]

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See detailClé d'identification des principales familles d'insectes d'Europe
Mignon, Jacques ULg; Haubruge, Eric ULg; Francis, Frédéric ULg

Book published by Presses agronomiques de Gembloux (2016)

Quelques insectes particuliers sont identifiables du premier coup d’œil ou par comparaison avec des illustrations de qualité. Malheureusement, il s’agit là d’exceptions et l’étude des insectes est souvent ... [more ▼]

Quelques insectes particuliers sont identifiables du premier coup d’œil ou par comparaison avec des illustrations de qualité. Malheureusement, il s’agit là d’exceptions et l’étude des insectes est souvent rendue complexe par la nécessité d’utiliser une loupe binoculaire et de maîtriser un vocabulaire spécifique difficilement accessible aux néophytes. Principalement destinée à l’enseignement de l’entomologie, la présente clé d’identification permet de donner un nom à quelque 180 familles ou super-familles d’insectes parmi les plus couramment rencontrées en Europe. Le vocabulaire utilisé est accessible à toute personne ayant des notions de base de la morphologie des insectes. Un glossaire et des figures permettent de combler certaines lacunes et de donner sens aux critères d’identification rencontrés. Reconnaître un insecte au niveau de la famille permet d’obtenir rapidement des précisions sur sa biologie et constitue une étape indispensable vers une connaissance approfondie des différentes espèces. [less ▲]

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See detailEarthworms Eisenia fetida affect the uptake of heavy metals by plants Vicia faba and Zea mays in metal-contaminated soils
Lemtiri, Aboulkacem ULg; Liénard, Amandine ULg; Alabi, Taofic ULg et al

in Applied Soil Ecology (2015)

Earthworms increase the availability of heavy metals in some situations and aid in maintaining the structure and quality of soil. The introduction of earthworms into metal-contaminated soils has been ... [more ▼]

Earthworms increase the availability of heavy metals in some situations and aid in maintaining the structure and quality of soil. The introduction of earthworms into metal-contaminated soils has been suggested as an aid for phytoremediation processes. In Wallonia, Belgium, a century of industrial metallurgic activities has led to the substantial pollution of soils by heavy metals, including copper (Cu), zinc (Zn), lead (Pb) and cadmium (Cd), due to atmospheric dusts. Two plant species, Vicia faba and Zea mays, and earthworms (Eisenia fetida) (Savigny, 1826) were exposed to different concentrations of long-term-contaminated soils for 42 days. The soil samples, which were collected from the land surrounding a former Zn-Pb ore-treatment plant, exhibited different levels of heavy metals. Our aim was to evaluate the role of earthworms E. fetida on the availability of metals in soils and their effects on metal uptake by V. faba and Z. mays plants at different soil concentrations. The results suggest that earthworms and plants modified the availability of metals in contaminated soils after 42 days of exposure. Earthworm life-cycle parameters were affected by metal contamination and/or the addition of plants; cocoon production and weight were more responsive to adverse conditions than earthworm survival or weight change. The concentrations of Pb and Cd in earthworm tissues decreased in the presence of plants. Results showed that metal accumulation in plants depended on the metal element considered and the presence of earthworms. However, the presence of earthworms did not change the concentrations of metals in plants, except for Cd. In the presence or absence of earthworms, V. faba accumulated higher concentrations of Cu and Zn compared with Z. mays, which accumulated higher concentrations of Cd. These findings have revealed that earthworm activities can modify the availability of heavy metals for uptake by plants in contaminated soils. Moreover, the study results show that the ecological context of phytoremediation should be broadened by considering earthworm-plant-soil interaction, which influence both the health of the plant and the uptake of heavy metals by plants. [less ▲]

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See detailA metagenomic approach from aphid’s hemolymph sheds light on the potential roles of co-existing endosymbionts
De Clerck, Caroline ULg; Fujiwara, Akiko; Joncour, Pauline et al

in Microbiome (2015), 3(63),

Background: Aphids are known to live in symbiosis with specific bacteria, called endosymbionts which can be classified as obligate or accessory. Buchnera aphidicola is generally the only obligatory ... [more ▼]

Background: Aphids are known to live in symbiosis with specific bacteria, called endosymbionts which can be classified as obligate or accessory. Buchnera aphidicola is generally the only obligatory symbiont present in aphids, supplying essential nutrients that are missing in the plants phloem to its host. Pentalonia nigronervosa is the main vector of the banana bunchy top virus, one of the most damageable viruses in banana. This aphid is carrying two symbionts: B. aphidicola (BPn) and Wolbachia sp. (wPn). The high occurrence of Wolbachia in the banana aphid raises questions about the role it plays in this insect. The goal of this study was to go further in the understanding of the role played by the two symbionts in P. nigronervosa. To do so, microinjection tests were made to see the effect of wPn elimination on the host, and then, high-throughput sequencing of the haemolymph was used to analyze the gene content of the symbionts. Results: We observed that the elimination of wPn systematically led to the death of aphids, suggesting that the bacterium could play a mutualistic role. In addition, we identify and annotate 587 and 250 genes for wPn and BPn, respectively, through high-throughput sequencing. Analysis of these genes suggests that the two bacteria are working together for the production of several essential nutrients. The most striking cases are for lysin and riboflavin which are usually provided by B. aphidicola alone to the host. In the banana aphid, the genes involved in the production pathways of these metabolites are shared between the two bacteria making them both essential for the survival of the aphid host. Conclusions: Our results suggest that a co-obligatory symbiosis between B. aphidicola and Wolbachia occurs in the banana aphid, the two bacteria acting together to supply essential nutrients to the host. This is, to our knowledge, the first time Wolbachia is reported to play an essential role in aphids. [less ▲]

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See detailUpdated checklist of the mosquitoes (Diptera: Culicidae) of Belgium
Boukraa, Slimane ULg; Dekoninck, Wouter; Versteirt, Veerle et al

in Journal of Vector Ecology : Journal of the Society for Vector Ecology (2015), 40(2), 398-407

Most information about the systematics and bioecology of Belgian mosquitoes dates back from before 1950, and only scattered information was produced during the last decades. In this paper we review and ... [more ▼]

Most information about the systematics and bioecology of Belgian mosquitoes dates back from before 1950, and only scattered information was produced during the last decades. In this paper we review and update the list of mosquito species recorded in Belgium, from first report (1908) to 2015. Six genera and 31 species were recorded so far, including 28 autochthonous species and three invasive alien species recently recorded in Belgium: Aedes albopictus (Skuse 1894), Ae. japonicus japonicus (Theobald 1901), and Ae. koreicus (Edwards 1917). The six genera are Anopheles (five species), Aedes (sixteen species), Coquillettidia (one species), Culex (four species), Culiseta (four species), and Orthopodomyia (one species). [less ▲]

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See detailLes insectes dans l'agriculture
Hatt, Séverin ULg; Francis, Frédéric ULg

Conference given outside the academic context (2015)

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See detailImpact of Regiella insecticola infection on EBF production in Acyrthosiphon pisum Harris
Bauwens, Julien ULg; Mazzucchelli, Gabriel ULg; De Pauw, Edwin ULg et al

Conference (2015, November 06)

Symbionts of aphids influence their host from many points of view. We investigate the potential influence of bacterial symbionts on the production and emission of the aphid alarm pheromone, E-β-franesene ... [more ▼]

Symbionts of aphids influence their host from many points of view. We investigate the potential influence of bacterial symbionts on the production and emission of the aphid alarm pheromone, E-β-franesene. Some trends could be observed in the total EβF production. Particularly, aphid strains infected by Buchnera only seemed to produce less alarm pheromone. By contrast, the presence of Regiella insecticola seemed to increase EβF production. Mevalonate pathway was investigated by RT-qPCR. This analysis showed a slightly lower transcription level o mIPPS in Regiella-infected strains. This enzyme is involved in the last step of EβF production. By contrast, two enzymes involved respectively in the linkage and release of farnesyl moeities on proteins c-terminal ends. Escape tests were conducted to assay if these results were traduced by differential behavior in front of a predator. Preliminary results showed significantly higher dropping behavior for Regiella-infected strains. [less ▲]

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See detailDo changes in atmospheric CO2 concentration affect aphid alarm signaling?
Boullis, Antoine ULg; Appeldoorn, Claire; Oostrom, Marjolein et al

Conference (2015, November 06)

The effects of global atmospheric changes on vegetation and associated insect populations are increasingly studied, but how these gases affect the interactions between herbivore insects and their natural ... [more ▼]

The effects of global atmospheric changes on vegetation and associated insect populations are increasingly studied, but how these gases affect the interactions between herbivore insects and their natural enemies is less clear. As the efficacy of natural enemies is governed largely by behavioral mechanisms, changes in the behavior of insect prey defenses can change the dynamics of insect populations. The impact of increases in atmospheric carbon dioxide (CO2) concentrations on aphid population dynamic is well documented. However, few publications about their chemical ecology are reported. Aphids are using many chemical signals to communicate with each other or with their environment. For example aphids produce an alarm pheromone to signal the presence of a natural enemy in the colony. For our experiments, aphids Acyrthosiphon pisum (Harris) were reared on Vicia faba L. in home-made Plexiglas® chambers, allowing us to control the CO2 concentration, temperature and humidity. Aphids were reared under both ambient (aCO2 ≈ 400 ppm) and elevated (eCO2 ≈ 800 ppm) CO2 concentration for several generations. Here we quantified the emission of (E)-β-Farnesene (EβF - main compound of alarm pheromone) released by predated aphids reared under ambient or elevated CO2 concentration, with two different methods: a real-time analysis, and the total amount analysis. The EβF content of whole aphid bodies was also analyzed, as well as the escape behavior of aphid colony according to the growing conditions of aphid populations. These results will be discussed in terms of biological control in future climate. [less ▲]

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See detailHemipteran - host plant interactions: focus on some model insect saliva
Serteyn, Laurent ULg; Moreau, Sophie; Delatour, Anaïs et al

Poster (2015, November)

Insect salivary components play important roles in plant-insect interactions, stimulating the plant defence or promoting infestation by manipulating plant physiology. Indeed, a variety of enzymes and ... [more ▼]

Insect salivary components play important roles in plant-insect interactions, stimulating the plant defence or promoting infestation by manipulating plant physiology. Indeed, a variety of enzymes and organic components in saliva of herbivory insects can induce series of biochemical responses in damaged plants. In our lab, several studies have been screening proteins in different aphid species saliva. The purpose of our current and future works is to widen that field of study to other piercing-sucking pests and host plants models. Three models will be compared: the pea aphid (Acyrtosiphon pisum Harris), the invasive Asian brown marmorated stink bug (Halyomorpha halys Stål) and the invasive South American green vegetable stink bug (Nezara viridula L.). A preliminary study showed differential expressions in bacterial proteins in salivary glands when N. viridula were exposed to tomato with or without glandular trichomes. This led to questioning whether the internal symbionts influence the adaptability of the pest to the host by manipulating saliva compounds. Then, a study can be led to assess the impact of symbiont profiles on pea aphid saliva proteins. We also began to analyse the impact of several diets on stink bugs salivary glands proteome. We use especially proteomic techniques, such as SDS-PAGE and 2D-DIGE followed by LC-MS/MS and MALDI-TOF analysis, but also liquid chromatography gel free approaches. The perspective would be applying saliva or salivary glands extracts on plant in order to screen its defensive responses by complementary “omic” approaches and, in term, to identify candidate proteins playing a role in plant defence induction or bypass. [less ▲]

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See detailSpecies diversity and abundance of aphids and their natural enemies in a crop association
Chevalier Mendes Lopes, Thomas ULg; Hatt, Séverin ULg; Starý, Petr et al

Poster (2015, November)

Crop associations can be efficient to reduce aphid populations, by disrupting the visual and olfactory location of host plants. However, increasing the chemical and structural complexity of vegetation can ... [more ▼]

Crop associations can be efficient to reduce aphid populations, by disrupting the visual and olfactory location of host plants. However, increasing the chemical and structural complexity of vegetation can also decrease the searching efficiency of predators and parasitoids, which are not always more abundant in complex habitats. Using attractive semiochemicals such as methyl salicylate (MeSA) combined with a crop association seems promising to maximise aphid control. We compared the abundances of aphids and their natural enemies between a wheat-pea mixture (with and without MeSA) and pure stands, using yellow traps and observations on plants. Significantly higher numbers of pea aphids (Acyrthosiphon pisum) were observed in the pure stand of pea compared with the mixture (with and without MeSA) in 2013 and 2014. Concerning aphid natural enemies, hoverfly larvae abundance was not significantly different between treatments in both years. Parasitoid mummies were significantly more abundant in the pure stand of pea compared with the mixture (with and without MeSA) in 2014. Fifty-two aphid species were collected in yellow traps, as well as 12 Aphidiinae and four Aphelinus species. Acyrthosiphon primulae, Aphelinus daucicola, Aphelinus fusciscapus, Aphidius asteris, Aphidius eadyi, Metopolophium frisicum, Praon barbatum, and Trioxys auctus were recorded for the first time in Belgium. Besides determining the effects of a wheat-pea mixture (with or without MeSA) on aphid control, this study contributed to increase the knowledge on aphid and their parasitoid diversity in Belgium, by recording new species and establishing the first Aphidiinae and Aphelinus national checklist. [less ▲]

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See detailFungal biofilm reactor improves the quality of a fusion protein GLA::GFP produced by Aspergillus oryzae
Zune, Quentin ULg; Delepierre, Anissa ULg; Bauwens, Julien ULg et al

Poster (2015, October)

Fungal biofilm is known to promote the excretion of secondary metabolites, in accordance with solid-state related physiological mechanisms. In this work, the potentialities of fungal biofilm will be ... [more ▼]

Fungal biofilm is known to promote the excretion of secondary metabolites, in accordance with solid-state related physiological mechanisms. In this work, the potentialities of fungal biofilm will be investigated in the context of the production of a Gla::GFP fusion protein by Aspergillus oryzae. Since the production of this protein is under the control of the promoter glaB, specifically induced in solid-state fermentation, biofilm mode of culture is expected to enhance the global productivity. However, we found that the glaB promoter is also activated in submerged bioreactor and the fusion protein production is higher in this mode of culture. This result is related to the high shear stress leading to biomass autolysis and leakage of intracellular fusion protein into the extracellular medium. Moreover, 2D-gel electrophoresis highlights preservation of the fusion protein integrity produced in biofilm conditions whereas proteolysis strongly affects fusion protein recovery in the submerged cultures performed at high stirring rate. Fungal biofilm reactor design was then further investigated and the scale-up potentialities were evaluated. Indeed, the specific design investigated in this work involves the use of metal structured packing exhibiting a high specific area and that can be easily expanded to large-scale bioprocessing conditions. [less ▲]

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