References of "Francis, Frédéric"
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See detailConsumer acceptance of insect-based alternative meat products in Western countries
Caparros Megido, Rudy ULiege; Gierts, Chloé; Blecker, Christophe ULiege 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 ULiege; Alabi, Taofic ULiege; 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 ULiege; 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 ULiege; Bawin, Thomas ULiege 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 ULiege; Bera, François ULiege; Lorge, Stéphanie ULiege 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 ULiege; Haubruge, Eric ULiege; Francis, Frédéric ULiege

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 detailA metagenomic approach from aphid’s hemolymph sheds light on the potential roles of co-existing endosymbionts
De Clerck, Caroline ULiege; 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 ULiege; 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 ULiege; Francis, Frédéric ULiege

Conference given outside the academic context (2015)

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See detailDo changes in atmospheric CO2 concentration affect aphid alarm signaling?
Boullis, Antoine ULiege; 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 detailImpact of Regiella insecticola infection on EBF production in Acyrthosiphon pisum Harris
Bauwens, Julien ULiege; Mazzucchelli, Gabriel ULiege; De Pauw, Edwin ULiege 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 detailMultitrophic interactions between plants-viruses-aphidiphagous
Bosquée, Emilie ULiege; Chevalier Mendes Lopes, Thomas ULiege; Boullis, Antoine ULiege et al

Conference (2015, November 06)

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See detailHemipteran - host plant interactions: focus on some model insect saliva
Serteyn, Laurent ULiege; 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 ULiege; Hatt, Séverin ULiege; 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 ULiege; Delepierre, Anissa ULiege; Bauwens, Julien ULiege 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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See detailWildflowers sown at field margins have positive and negative effects on pests and parasitoids
Hatt, Séverin ULiege; Uyttenbroeck, Roel ULiege; Chevalier Mendes Lopes, Thomas ULiege et al

Conference (2015, September 03)

Wildflower strips are sown at field margins throughout Europe to support insect conservation in agricultural areas. Among other insects, parasitoids may favor a biological regulation of pests. On an ... [more ▼]

Wildflower strips are sown at field margins throughout Europe to support insect conservation in agricultural areas. Among other insects, parasitoids may favor a biological regulation of pests. On an experimental field of the research platform AgricultureIsLife in Gembloux (University of Liège, Belgium), three replications of five wildflower seed mixtures were sown in strips adjacent to crops in spring 2013. Insect pests and their parasitoids were pan-trapped in spring 2014 in both wildflower strips and oilseed rape crops and identified at the species level. Flower species and cover were monitored in the strips using 1 m² quadrats, before mowing. Meligethes spp. were found abundantly in crops when oilseed rape was blooming. Meligethes’ parasitoids occurred later and their abundance was positively correlated with that of Meligethes in the flower strips. At the crop ripening stage, weevils Ceutorhynchus spp. occurred and were followed by an increase in abundance of their parasitoids in both crops and flowers. Positive as well as negative correlations were found between the abundance of these pests, their parasitoids and different flower species blooming at this time. The link between these results with flower species’ functional traits will be discussed. [less ▲]

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See detailDoes combining a wheat and pea mixture with methyl salicylate reduces aphid populations in both crops?
Chevalier Mendes Lopes, Thomas ULiege; Fassotte, Bérénice ULiege; Hatt, Séverin ULiege et al

Conference (2015, August 25)

Aphids are important pests of wheat and pea. Among the alternative methods to control them with less reliance on insecticides, crop associations already proved to be efficient. However, if increasing the ... [more ▼]

Aphids are important pests of wheat and pea. Among the alternative methods to control them with less reliance on insecticides, crop associations already proved to be efficient. However, if increasing the chemical and structural complexity of vegetation can disrupt their host plants location, the searching efficiency of predators and parasitoids can also be reduced. Therefore, these beneficials may not always be more abundant in such systems. Combining crop associations with attractive semiochemicals for natural enemies can be interesting to solve this problem. In this research, we compared the effect of a wheat and pea pure stand, wheat and pea mixture, and wheat and pea mixture combined with methyl salicylate (MeSA) formulated in alginate gel beads, on the abundance and diversity of aphids and their natural enemies. These were weekly observed on plants during 2013 and 2014 growing seasons. Over these two years, significantly higher numbers of pea aphids (Acyrthosiphon pisum (H.)) were observed in the pure stand of pea compared with both mixtures (with and without MeSA). No significant differences were observed between treatments for wheat aphids (Sitobion avenae (F.), Metopolophium dirhodum (W.) and Rhopalosiphum padi (L.)), which were significantly less abundant than pea aphids. Aphid natural enemies were mainly observed on pea plants. Hoverfly larvae abundance was not significantly different between treatments during both years. The same phenomenon occurred with hoverfly pupae in 2013, while these were significantly more abundant in both mixtures compared with the pure stand in 2014. However, their number did not differ significantly between the mixture with and without MeSA. Few ladybirds and lacewings were observed. No significant differences were observed between treatments for parasitoid mummies in 2013. Their abundance was significantly higher in the pure stand of pea compared with both mixtures in 2014. Results from this study show that mixing wheat and pea is an efficient method to maintain aphid populations at a very low level on pea. The use of MeSA did not show significant effects on natural enemies. However, mixing these crops may be enough to reduce aphid populations under an acceptable threshold. [less ▲]

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See detailTuta absoluta (Lepidoptera: Gelechiidae) development on wild and cultivated plant species
Bawin, Thomas ULiege; Dujeu, David ULiege; Fagan, Maud et al

Conference (2015, August 24)

Introduction: The tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), is a widespread invasive species damaging economically important solanaceous crop plants, including tomatoes and potatoes ... [more ▼]

Introduction: The tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), is a widespread invasive species damaging economically important solanaceous crop plants, including tomatoes and potatoes. Little is known about the ability of the microlepidoptera to encounter and develop on alternative wild and agricultural plant species. These plants could provide refuges and have to be identified for more efficient integrated management strategies. Objectives: In the present study, we assessed under laboratory conditions the ability of T. absoluta to develop on such plant species referred as potential hosts in the literature, including Solanaceae, Chenopodiaceae, Convolvulaceae, Fabaceae, and Malvaceae. Materials and methods: For each plant species, fitness tests were performed in Petri dishes by isolating single individuals with excised leaf. Two choice behavioral assays were performed in flying tunnels. Volatile organic compounds released by solanaceous plants were trapped using a dynamic collection system, and analyzed by GC-MS. Results: We found that Solanum species allowed higher larval survivability and shorter development time (from egg to adult emergency) compared to the other plants. Non-solanaceous plants were not able to sustain T. absoluta larvae. Two choice behavioral assays revealed that adult distribution and female oviposition did not differ between Solanum species, which were preferred to other tested solanaceous plants. The hypothesis that female host plant choice is influenced by plant volatile organic compounds was tested. Solanum volatile profiles showed similarities, and were presenting quantitative and qualitative differences with the other tested solanaceous plants, providing some explanations in the observed behavioral discrimination. Further electrophysiological and behavioral assays are required to confirm the effect of specific chemicals on the choice of the oviposition site in T. absoluta. Conclusion: It can be concluded that Solanum species are the more suitable hosts for T. absoluta development. Other solanaceous plant species could be opportunistically colonized with little incidence but care should be taken in these results as genetic variability in insects and plants, as well as plant physiological state, might have an impact on the pest survivability. [less ▲]

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