References of "Francis, Frédéric"
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See detailA push–pull strategy to control aphids combines intercropping with semiochemical releases
Xu, Qingxuan ULg; Hatt, Séverin ULg; Chevalier Mendes Lopes, Thomas ULg et al

in Journal of Pest Science (in press)

Even if insect pest populations can be reduced by increasing plant diversity through intercropping, natural enemies are not always favored in such systems. Alternatively, semiochemical substances have ... [more ▼]

Even if insect pest populations can be reduced by increasing plant diversity through intercropping, natural enemies are not always favored in such systems. Alternatively, semiochemical substances have been tested to enhance biological control, with inconsistent results. Combining both strategies can be an interesting way to maximize pest control. In this work, a 2-year setup involving wheat–pea strip intercropping combined with the release of E-b-farnesene (EBF) or methyl salicylate (MeSA) was tested as a push–pull strategy to simultaneously repel aphids and attract beneficials. Two types of slow-release formulation (i.e., oil and alginate beads) containing EBF or MeSA were deployed with the intercropping. The abundance of aphids was significantly decreased, while hoverfly larvae and mummified aphids increased on both pea plants and wheat tillers by the release of oil-formulated EBF and MeSA. The proportion parasitism of the aphid-parasitism rate [mummies/(aphids + mummies)] was also increased by treating both crops in both years. Releasing EBF through oil rather than alginate beads proved significantly better for attracting natural enemies and reducing aphids. Aphids were negatively correlated with the density of hoverflies (both adults and larvae) and numbers of mummies. All these results showed that combining intercropping with the release of EBF or MeSA formulated in oil can significantly reduce aphid density and attract their natural enemies. Therefore, the combination of both strategies could help farmers reduce the use of insecticides. [less ▲]

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See detailNine facultative endosymbionts in aphids. A review
Guo, Jianqing ULg; Hatt, Séverin ULg; He, Kanglai et al

in Journal of Asia-Pacific Entomology (in press)

Aphids are frequently engaged in mutualistic associations with endosymbionts. Symbionts are bacterial or fungal microorganisms that can be obligate or facultative to aphids. Research showed facultative ... [more ▼]

Aphids are frequently engaged in mutualistic associations with endosymbionts. Symbionts are bacterial or fungal microorganisms that can be obligate or facultative to aphids. Research showed facultative (or secondary) symbionts have numerous effects on their host aphids such as resistance to heat shock, parasitoids and fungus etc., which may consequently promote a co-evolution between symbionts and hosts. However, this symbiotic relation may be affected by several factors, such as the ability of symbionts to spread from aphids to others within and across populations, and the cost of infections for hosts. Moreover, aphid-symbionts interactions may be affected by aphid living environment such as its host plant, the presence of natural enemies or the temperature. Here we firstly described the functions of nine facultative symbionts (Serratia symbiotica, Hamiltonella defensa, Regiella insecticola, Rickettsia, Rickettsiella, PAXS (pea aphid X-type symbiont), Spiroplasma, Wolbachia and Arsenophonus) studied in aphids one by one, and discussed the associations between these symbionts and aphids, plants and environment. We aim to have a better knowledge of the roles the facultative symbionts play in aphid biology, ecology and evolution, which we believe can provide new inspirations for aphid control. [less ▲]

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See detailIdentification of proteins from wild cardoon flowers (Cynara cardunculus L.) by a proteomic approach
Ben Amira, Amal; Bauwens, Julien ULg; De Pauw, Edwin ULg et al

in Journal of Chemical Biology (in press)

Proteomic approach was applied to identify total proteins, particularly the enzymatic content, from wild cardoon flowers. As the selection of an appropriate sample preparation method is the key for ... [more ▼]

Proteomic approach was applied to identify total proteins, particularly the enzymatic content, from wild cardoon flowers. As the selection of an appropriate sample preparation method is the key for getting reliable results, two different extraction/precipitation methods (trichloroacetic acid and phenol/ammonium acetate) were tested on fresh and lyophilized flowers. After two-dimensional electrophoresis (2D–E) separations, a better protein pattern was obtained after phenol extraction from lyophilized flowers. Only 46 % of the total analyzed spots resulted in a protein identification by mass spectrometry MALDI-TOF. Four proteases (cardosins A, E, G, and H), which have become a subject of great interest in dairy technology, were identified. They presented molecular weights and isoelectric points very close and high levels of homology between matched peptides sequences. The absence of the other cardosins (B, C, D, and F) could be an advantage, as it reduces the excessive proteolytic activity that causes bitter flavors and texture defects, during cheese making. [less ▲]

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See detailInsect fatty acids: A comparison of lipids from three Orthopterans and Tenebrio molitor L. larvae
Paul, Aman ULg; Frederich, Michel ULg; Caparros Megido, Rudy ULg et al

in Journal of Asia-Pacific Entomology (2017), 20(2), 337-340

In order to explore some potential insect sources of food lipids, the lipid compositions of three Orthopterans (Acheta domesticus, Conocephalus discolor and Chorthippus parallelus) were analyzed and ... [more ▼]

In order to explore some potential insect sources of food lipids, the lipid compositions of three Orthopterans (Acheta domesticus, Conocephalus discolor and Chorthippus parallelus) were analyzed and compared with those of Tenebrio molitor larvae. A. domesticus, Co. discolor, Ch. parallelus and T. molitor larvae were found to contain approximately 15%, 13%, 10% and 32% lipids on dry weight, respectively. The lipids from three Orthopterans contain much higher amounts of essential fatty acids than those of T. molitor larvae. The two Orthopterans of the suborder Ensifera i.e., A. domesticus and Co. discolor contain linoleic acid in major quantities, while Ch. parallelus of the suborder Caelifera, contain α-linolenic acid in major quantities. The consumption of linoleic and α-linolenic fatty acid is linked with numerous health promoting effects. The factors that contribute to differences in fatty acid profiles of these insects are being discussed. At last the nutritional parameters including polyunsaturated to saturated and omega 6 to omega 3 fatty acid ratios of these insect lipids are also being discussed to understand the potential role of these lipids in human nutrition. [less ▲]

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See detailStress indicator gene expression profiles, colony dynamics and tissue development of honey bees exposed to sub-lethal doses of imidacloprid in laboratory and field experiments
De Smet, Lina; Hatjina; Ioannidis, Pavlos et al

in PLOS One (2017), 10(137),

In this study, different context-dependent effects of imidacloprid exposure on the honey bee response were studied. Honey bees were exposed to different concentrations of imidacloprid during a time period ... [more ▼]

In this study, different context-dependent effects of imidacloprid exposure on the honey bee response were studied. Honey bees were exposed to different concentrations of imidacloprid during a time period of 40 days. Next to these variables, a laboratory-field comparison was conducted. The influence of the chronic exposure on gene expression levels was determined using an in-house developed microarray targeting different immunity-related and detoxification genes to determine stress-related gene expression changes. Increased levels of the detoxification genes encoding, CYP9Q3 and CYT P450, were detected in imidacloprid- exposed honey bees. The different context-dependent effects of imidacloprid exposure on honey bees were confirmed physiologically by decreased hypopharyngeal gland sizes. Honey bees exposed to imidacloprid in laboratory cages showed a general immunosuppression and no detoxification mechanisms were triggered significantly, while honey bees infield showed a resilient response with an immune stimulation at later time points. However, the treated colonies had a brood and population decline tendency after the first brood cycle in the field. In conclusion, this study highlighted the different context-dependent effects of imidacloprid exposure on the honey bee response. These findings warn for possible pitfalls concerning the generalization of results based on specific experiments with short exposure times. The increased levels of CYT P450 and CYP9Q3 combined with an immune response reaction can be used as markers for bees which are exposed to pesticides in the field. [less ▲]

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See detailStructure and distribution of the sensilla on the antennae of Tuta absoluta (Lepidoptera: Gelechiidae)
Bawin, Thomas ULg; Collard, France ULg; De Backer, Lara ULg et al

in Micron (2017), 96

The tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), is a widespread devastating pest that develops on tomato and other economically important solanaceous crops. Current semiochemically-based ... [more ▼]

The tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), is a widespread devastating pest that develops on tomato and other economically important solanaceous crops. Current semiochemically-based management strategies still fail to significantly reduce damages and need to be improved. Here we describe under scanning and transmission electron microscopy the structure and distribution of the sensilla that are displayed on adult antennae. These were similar in size between males (3424.4 ± 135.3 μm) and females (3292.1 ± 111.5 μm), being segmented into a scape, a pedicel, and a distal filiform flagellum. Eight morphological sensilla types were observed on both sexes: Böhm’s bristles, sensilla squamiformia, sensilla trichodea, sensilla basiconica (two subtypes), sensilla chaetica, sensilla coeloconica, sensilla auricillica, and sensilla styloconica. The main sexual dimorphism was related to the higher abundance of sensilla trichodea in males, twice as abundant as in females. The putative functional significance of the different sensilla types regarding the insect ecology is discussed based on the available literature. This work provides descriptions of the antennae and related sensory structures. We expect these results to help develop further electrophysiological investigations aiming to a better understanding of T. absoluta olfaction. [less ▲]

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See detailMicrobiological load of edible insects found in Belgium
Caparros Megido, Rudy ULg; Desmedt, Sandrine; Blecker, Christophe ULg et al

in Insects (2017)

Edible insects are gaining more and more attention as a sustainable source of animal protein for food and feed in the future. In Belgium, some insect products can be found on the market, and consumers are ... [more ▼]

Edible insects are gaining more and more attention as a sustainable source of animal protein for food and feed in the future. In Belgium, some insect products can be found on the market, and consumers are sourcing fresh insects from fishing stores or towards traditional markets to find exotic insects that are illegal and not sanitarily controlled. From this perspective, this study aims to characterize the microbial load of edible insects found in Belgium (i.e., fresh mealworms and house crickets from European farms and smoked termites and caterpillars from a traditional Congolese market) and to evaluate the efficiency of different processing methods (blanching for all species and freeze-drying and sterilization for European species) in reducing microorganism counts. All untreated insect samples had a total aerobic count higher than the limit for fresh minced meat (6.7 log cfu/g). Nevertheless, a species-dependent blanching step has led to a reduction of the total aerobic count under this limit, except for one caterpillar species. Freeze-drying and sterilization treatments on European species were also effective in reducing the total aerobic count. Yeast and mold counts for untreated insects were above the Good Manufacturing Practice limits for raw meat, but all treatments attained a reduction of these microorganisms under this limit. These results confirmed that fresh insects, but also smoked insects from non-European trades, need a cooking step (at least composed of a first blanching step) before consumption. Therefore, blanching timing for each studied insect species is proposed and discussed. [less ▲]

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See detailElevated carbon dioxide concentration reduces alarm signaling in aphids
Boullis, Antoine ULg; Fassotte, Bérénice ULg; Sarles, Landry ULg et al

in Journal of Chemical Ecology (2017), 43

Insects often rely on olfaction to communicate with surrounding conspecifics. While the chemical language of insects has been deciphered in recent decades, few studies have assessed how changes in ... [more ▼]

Insects often rely on olfaction to communicate with surrounding conspecifics. While the chemical language of insects has been deciphered in recent decades, few studies have assessed how changes in atmospheric greenhouse gas concentrations will impact pheromonal communication by insects. Here, we hypothesize that changes in the concentration of atmospheric carbon dioxide (CO2) affect the whole dynamics of alarm signaling in aphids, including: (1) the production of the active compound (E)-β-farnesene (Eβf), (2) emission behavior when under attack, (3) perception by the olfactory apparatus, and (4) the escape response. We reared two strains of the pea aphid Acyrthosiphon pisum under ambient and elevated CO2 concentrations for several generations. We found that an increase in CO2 concentration reduced the production (i.e., individual content) and emission of Eβf (released under predation events). While no difference in Eβf neuronal perception was observed, we found that an increase in CO2 strongly reduces the escape behavior expressed by an aphid colony following exposure to natural doses of the alarm pheromone. In conclusion, our results confirm that changes to greenhouse gases do impact chemical communication in insects, and could potentially have a cascade effect on interactions with higher trophic levels. [less ▲]

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See detailLooking for phosphate-accumulating bacteria in activated sludge processes : a multidisciplinary approach
Tarayre, Cédric ULg; Charlier, Raphaëlle; Delepierre, Anissa ULg et al

in Environmental Science and Pollution Research (2017)

Over the past decades, an increasing need in renewable resources has progressively appeared. This trend concerns not only fossil fuels but also mineral resources. Wastewater and sewage sludge contain ... [more ▼]

Over the past decades, an increasing need in renewable resources has progressively appeared. This trend concerns not only fossil fuels but also mineral resources. Wastewater and sewage sludge contain significant concentrations in phosphate and can be considered as a fertilizer source of the utmost importance. In wastewater treatment plants, the biological uptake of phosphate is performed by a specific microbiota: the phosphate-accumulating organisms. These microorganisms are recovered in sewage sludge. Here, we aimed to investigate the occurrence of phosphate accumulators in four wastewater treatment plants. A 16S metagenetic analysis identified the main bacterial phyla extracted from the aerobic treatment: α-Proteobacteria, β-Proteobacteria, and Sphingobacteria. An enrichment stage was performed to stimulate the specific growth of phosphate-accumulating bacteria in an acetate medium. An analysis of metabolic activities of sulfur and phosphorus highlighted strong modifications related to phosphorus and much less distinguishable effects with sulfur. A solid acetate medium containing 5-Br-4-Cl-3-indolyl phosphate was used to select potential phosphate-accumulating bacteria from the enriched consortia. The positive strains have been found to belong in the genera Acinetobacter, Corynebacterium, and Pseudomonas. Finally, electron microscopy was applied to the strains and allowed to confirm the presence of polyphosphate granules. Some of these bacteria contained granules the size of which exceeded 100 nm. [less ▲]

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See detailUsutu virus, Belgium, 2016
Garigliany, Mutien-Marie ULg; Linden, Annick ULg; Gilliaux, Gautier ULg et al

in Infection, Genetics and Evolution : Journal of Molecular Epidemiology and Evolutionary Genetics of Infectious Diseases (2017), 48(1), 116-119

During late summer 2016, in a northwest European region extending over Belgium, the Netherlands and the eastern border of the German state of North Rhine Westphalia, an outbreak of wild bird deaths ... [more ▼]

During late summer 2016, in a northwest European region extending over Belgium, the Netherlands and the eastern border of the German state of North Rhine Westphalia, an outbreak of wild bird deaths occurred similar to those reported on the continent since 1996. Dead birds were necropsied and examined by complementary methods. Pathologic and immunohistological investigations strongly suggested an infection by Usutu virus. Subsequently, genomic segments of the said virus were detected, the virus was isolated and its complete genome was sequenced. The strain, designated Usutu-LIEGE, is a close phylogenetic relative of those isolated in Germany which form a distinct group within the USUV phylogeny, the so-called Europe_3 lineage. Should this outbreak recapitulate the characteristics of those in southwest Germany in 2011 and in/around Vienna (Austria) in 2001, it is expected that specific avian populations in the affected area will face a significant reduction in size for a few years. [less ▲]

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See detailThe Odor of Death: An Overview of Current Knowledge on Characterization and Applications
Verheggen, François ULg; Perrault, Katelynn ULg; Caparros Megido, Rudy ULg et al

in Bioscience (2017)

After death, the human body undergoes various processes that result in the emission of volatile organic compounds (VOCs). The interest in these VOCs has increased substantially in recent years because ... [more ▼]

After death, the human body undergoes various processes that result in the emission of volatile organic compounds (VOCs). The interest in these VOCs has increased substantially in recent years because they are key attractants for necrophagous insects and vertebrate scavengers. Identifying cadaveric VOCs has required the effective development of analytical tools for collecting, separating, identifying, and quantifying the suite of VOCs released throughout decomposition. Analytical developments for studying cadaveric VOCs in vertebrates, ecological interactions of cadaveric VOCs with the abiotic and biotic environment, and the necessity for convergence of these two areas for the progression of future knowledge are discussed herein. [less ▲]

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See detailParasitisme d’Apis mellifera adansonii (Latreille 1804) et de Meliponula bocandei (Spinola 1853) par Aethina tumida (Murray 1867): premier recensement au Gabon et impact sur la domestication
Fabre Anguilet, Edgard ULg; Alabi, Taofic ULg; Haubruge, Eric ULg et al

in Entomologie Faunistique = Faunistic Entomology (2017), 70

The small hive beetle, Aethina tumida (Murray 1867), has been reported in many countries in sub-Saharan Africa. This parasite is considered as a minor threat to strong Apis mellifera (Linnaeus 1758 ... [more ▼]

The small hive beetle, Aethina tumida (Murray 1867), has been reported in many countries in sub-Saharan Africa. This parasite is considered as a minor threat to strong Apis mellifera (Linnaeus 1758) colonies in Africa and as a major threat during the transfer of wild colonies of Meliponula bocandei (Spinola 1853) in hives. There is no data for Gabon and the state of wild colonies is still poorly known. Then, this study aims (1) to make a first prevalence assessment of A. tumida in wild colonies of A. mellifera and M. bocandei in Gabon; (2) to verify the effectiveness of quarantine implementation during the transfer of M. bocandei in hives against A. tumida. For that, 59 nests of A. mellifera and 25 nests of M. bocandei were inspected in two locations. Twelve nests of M. bocandei were transferred in hives with a quarantine for 4 days while 12 nests were transferred without quarantine. Aethina tumida was observed in more than 70 % of A. mellifera nests and in a single nest of M. bocandei. No damage was observed in nests of A. mellifera. More than 60 % of brood sections in quarantine or not were destroyed by A. tumida in hives. This study provided first evidence of the presence of A. tumida in Gabon and the need to develop a more effective method to domesticate M. bocandei in hives. [less ▲]

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See detailIdentification of walnut husk (Juglans regia L.) volatiles and the behavioural response of the invasiveWalnut Husk Fly, Rhagoletis completa Cresson
Sarles, Landry ULg; Boullis, Antoine ULg; Fassotte, Bérénice ULg et al

in Pest Management Science (2017)

Abstract BACKGROUND: Several European countries are important walnut (Juglans regia L.) producers. However, these countries must contendwith the recent introduction of theWalnut Husk Fly,Rhagoletis ... [more ▼]

Abstract BACKGROUND: Several European countries are important walnut (Juglans regia L.) producers. However, these countries must contendwith the recent introduction of theWalnut Husk Fly,Rhagoletis completa Cresson (Diptera, Tephritidae),which is causing severe economic losses, especially in organic production. Because most Tephritid fruit flies use kairomones in their search for host plants, we hypothesise that this highly specialist species orients toward the volatile blend released by walnut husks. RESULTS:We collected, identified, and quantified the volatile organic chemicals (VOCs) released by walnut husks from themost commonly cultivated variety in France (Franquette). Then, the behavioural response of R. completa toward synthetic odour blends was recorded in dual choice assays conducted in net cages. A total of 26 VOCs were identified, with 𝜶-pinene, 𝜷-pinene, trans-linalool, eugenol, and tetradecane representing the major constituents. In the dual choice assay, male and female R. completa were strongly attracted to synthetic blend that includedmost of the identified husk VOCs. CONCLUSION:When searching for a host plant, R. completa use host fruit kairomones. The potential of these semiochemicals in monitoring andmanagement of this quarantine pest is discussed. [less ▲]

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See detailAbondance et diversité des communautés lombriciennes dans la Réserve et Domaine de Chasse de Bombo-Lumene (Kinshasa)
Milau Empwal, Fils; Lemtiri, Aboulkacem ULg; KIFUKIETO MANZANZA, Carmel et al

in Int. J. Biol. Chem. Sci (2017)

Les vers de terre sont des espèces importantes des écosystèmes édaphiques dotées des capacités de transformer leur biotope et même parfois de créer de nouveaux habitats pour d’autres organismes. En effet ... [more ▼]

Les vers de terre sont des espèces importantes des écosystèmes édaphiques dotées des capacités de transformer leur biotope et même parfois de créer de nouveaux habitats pour d’autres organismes. En effet, ils modifient la morphologie, la structure et la composition du sol par leur action à la fois physique, chimique et biologique. Ils ont ainsi une implication intéressante dans la fertilité et le cycle des nutriments du sol. Cette étude a été effectuée dans la Réserve et Domaine de Chasse de Bombo-Lumene (RDCBL) à Kinshasa. Elle avait pour objectif d’évaluer l’effet de l’occupation du sol sur la composition et la structure des communautés lombriciennes. Dix-huit parcelles regroupées en 6 biotopes ont été échantillonnées: les forêts denses semi décidues, les galeries forestières, les recrûs forestiers, les savanes arborescentes, les savanes herbeuses, et les sols sous culture. Au total, 10 espèces de vers de terre ont été identifiées. Elles appartiennent aux deux grandes familles tropicales : celle des Acanthodrilidae et celle des Eudrilidae. Les biotopes naturels sont les plus riches en termes de richesse d’espèces comparés aux biotopes les plus anthropisés. Dans cette étude, le type d’occupation du sol affecte considérablement la diversité des vers de terre. [less ▲]

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See detailCooking Has Variable Effects on the Fermentability in the Large Intestine of the Fraction of Meats, Grain Legumes, and Insects That Is Resistant to Digestion in the Small Intestine in an in Vitro Model of the Pig’s Gastrointestinal Tract
POELAERT, Christine ULg; Despret, Xavier; Sindic, Marianne ULg et al

in Journal of Agricultural and Food Chemistry (2017), 65

This study aimed to evaluate the fermentation in the large intestine of indigestible dietary protein sources from animal, insect, and plant origin using an in vitro model of the pig’s gastrointestinal ... [more ▼]

This study aimed to evaluate the fermentation in the large intestine of indigestible dietary protein sources from animal, insect, and plant origin using an in vitro model of the pig’s gastrointestinal tract. Protein sources were used raw and after a cooking treatment. Results showed that the category of the ingredient (meats, insects, or grain legumes) exerts a stronger impact on enzymatic digestibility, fermentation patterns, and bacterial metabolites such as short-chain fatty acids (SCFA) and hydrogen sulfide (H2S) than the cooking treatment. The digestibility and the fermentation characteristics of insects were more affected by the cooking procedure than the other categories. Per gram of consumed food, ingredients from animal origin, namely, meats and insects, were associated with fewer fermentation end-products (gas, H2S, SCFA) than ingredients from plant origin, which is related to their higher small intestinal digestibility. [less ▲]

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See detailDo flower mixtures with high functional diversity enhance aphid predators in wildflower strips?
Hatt, Séverin ULg; Uyttenbroeck, Roel ULg; Chevalier Mendes Lopes, Thomas ULg et al

in European Journal of Entomology (2017), 114

Among semi-natural elements in agricultural landscapes, wildflower strips sown at field margins or within fields represent potential habitats for the natural enemies of insect pests. As insects are ... [more ▼]

Among semi-natural elements in agricultural landscapes, wildflower strips sown at field margins or within fields represent potential habitats for the natural enemies of insect pests. As insects are sensitive to a variety of flower traits, we hypothesised that mixtures with high functional diversity attract and support a higher abundance and species richness of aphid flower visiting predators compared to mixtures with low functional diversity. During a field experiment, repeated over two years (2014 and 2015) in Gembloux (Belgium), aphid predators (i.e., lacewings, ladybeetles and hoverflies) were pan-trapped in five sown flower mixtures (including a control mixture, with three replicates of each mixture) of low to high functional diversity based on seven traits (i.e., flower colour, ultra-violet reflectance and pattern, blooming start and duration, height and flower class, primarily based on corolla morphology). In both years, flower species in the sown mixtures (i.e., sown and spontaneous flowers) were listed, and the realised functional diversity of each plot was calculated. Over the two years, an increase in functional diversity did not result in an increase in the abundance and richness of aphid predators. Moreover, ladybeetles, representing the majority of trapped predators, were more abundant in mixtures with very low or intermediary functional diversity at sowing, especially in 2014. We hypothesise that certain flower species, which were abundant in certain mixtures (and not in those exhibiting the highest functional diversity), attracted predators and were sufficiently represented to support them. Our results present novel information that could be used to the development of flower mixtures that provide effective ecosystem services, such as pest control. [less ▲]

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See detailPest regulation and support of natural enemies in agriculture: Experimental evidence of within field wildflower strips
Hatt, Séverin ULg; Chevalier Mendes Lopes, Thomas ULg; Boeraeve, Fanny ULg et al

in Ecological Engineering (2017), 98

tRestoring ecosystem services in agriculture is vital to reach a sustainable food production. More specif-ically, developing farming practices which enhance biological pest control is a main issue for ... [more ▼]

tRestoring ecosystem services in agriculture is vital to reach a sustainable food production. More specif-ically, developing farming practices which enhance biological pest control is a main issue for today’sagriculture. The aim of this study was to assess whether the two strategies of complicating the search ofhost plants by pests by increasing plant diversity, and of supporting their natural enemies by managinghabitats, could be combined simultaneously at the field scale to restore biological pest control and reducechemical insecticide use. In Gembloux (Belgium), wildflower strips (WFS) were sown within wheat cropsin which pests (i.e., aphids), their predators (i.e. aphidophagous hoverflies, lacewings and ladybeetles)and parasitoid wasps were monitored for 10 weeks in the period of May through July 2015 as indicatorsof the ES of pest control. Aphids were significantly reduced and adult hoverflies favoured in wheat inbetween WFS, compared to monoculture wheat plots. No significant differences were observed for adultlacewings, ladybeetles and parasitoids. In all treatments, very few lacewing and ladybeetle larvae wereobserved on wheat tillers. The abundance of hoverfly larvae was positively correlated with the aphid den-sity on tillers in between WFS, showing that increasing food provisions by multiplying habitats withinfields, and not only along margins, can help supporting aphidophagous hoverflies in crops. By enhancingthe ecosystem services of biological pest control, this study shows that increasing both plant diversityand managing habitats for natural enemies may reduce aphid populations, hence insecticide use. Futureresearch should continue this vein of work by quantifying the link between agricultural practices and thedelivery of ecosystem services in order to guide future measures of agricultural policies. [less ▲]

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See detailInsects complex associated with the tropical basil, Ocimum gratissimum L. (Lamiaceae) in southern Benin.
Yarou, Boni Barthélémy ULg; Bokonon-Ganta, H. Aimé; Assogba Komlan, Françoise et al

Poster (2016, December 16)

Tropical basil is an aromatic leafy vegetable used for its medicinal and therapeutic properties in numerous countries in West Africa (Benin, Nigeria, Togo, etc.). In Benin, it is produced on almost all ... [more ▼]

Tropical basil is an aromatic leafy vegetable used for its medicinal and therapeutic properties in numerous countries in West Africa (Benin, Nigeria, Togo, etc.). In Benin, it is produced on almost all urban and periurban garden throughout the year for fresh market. Until now there are few or nearly no publications about the arthropod community of this specie, even less in the context of Benin. Thus, to assess this community, basil plots were mowed using a sweep net in three localities (Ouidah, Togba and Sèmè) of southern Benin. Preliminary results focus on the different insect families that colonized tropical basil in southern Benin environmental conditions. These include: Aphididae (Homoptera), Cercopidae (Homoptera), Chrysomelidae (Coleoptera), Coccinelledidea (Coleoptera), Meloidae (Coleoptera), Braconidae (Hymenoptera), Ichneumonidae (Hymenoptera), Formicidae (Hymenoptera), Vespidae (Hymenoptera), Apoidae (Hymenoptera), Reduviidae (Heteroptera), Pentatomidae (Heteroptera), Pyrgomorphidae (Orthoptera), Acrididae (Orthoptera), Syrphidae (Diptera), Diopsidae (Diptera). Among these families, there are pests: Aphis gossypii G. (Homoptera: Aphididae), Zonocerus variegatus L. (Orthoptera: Pyrgomorphidae), etc.; predators: Ischiodon aegyptius W. (Diptera: Syrphidae), Cheilomenes spp. (Coleoptera: Coccinelledidea), Rhynocoris spp. (Heteroptera: Reduviidae), etc.; parasitoids and pollinators. From this study, it appeared that there is a large diversity of families and functional groups (pests, predators, parasitoids and pollinators) associated with tropical basil . Moreover, the presence of natural enemies could be an advantage for farmers in intercropping systems. This would help reduce the use of synthetic insecticides. This result, which is a first knowledge of the insect fauna associated with tropical basil under the environmental conditions of Southern Benin, will be supplemented by a spatio temporal study to assess the variability and the dynamics of this insect fauna. [less ▲]

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See detailTuta absoluta (Lepidoptera: Gelechiidae) ability to develop on potato tubers
Bawin, Thomas ULg; De Backer, Lara ULg; Yarou, Boni Barthélémy ULg et al

Poster (2016, December 16)

Tuta absoluta (Lepidoptera: Gelechiidae) is a widespread pest that threatens commercial production of solanaceous crops. Larvae feed on the mesophyll of all aerial parts of the plants resulting in ... [more ▼]

Tuta absoluta (Lepidoptera: Gelechiidae) is a widespread pest that threatens commercial production of solanaceous crops. Larvae feed on the mesophyll of all aerial parts of the plants resulting in significant yield losses and cosmetic damages.It is classically assumed that underground plant parts are not affected but larval development on potato tubers has recently been suspected. However, this assumption is poorly supported in the literature. Potato tubers might represent an unsuspected mean of persistence and dispersal in agricultural environments.Oviposition tests were here conducted using dormant and active (sprouts less than 5 cm) potato tubers in net cages. Oviposition only occurred on the sprouts of active tubers, supporting larval growth until adult emergency. Tuber dissection revealed burrows starting from sprouts inside the flesh. Additional fitness assays were conducted on non-sprouted tubers and revealed that first instar larvae were able to enter the skin and create burrows, living inside and feeding on potato flesh, although none of them survived. [less ▲]

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See detailThe Impact of Diseases Transmission in Pollinators Decline
Noël, Grégoire ULg; Bebermans, Julien ULg; Colinet, Frédéric ULg et al

Scientific conference (2016, December 02)

Ongoing global biodiversity loss is a growing concern for our society. This involves also the pollinators community which ensures insect-pollinated plant reproduction in our natural environment and ... [more ▼]

Ongoing global biodiversity loss is a growing concern for our society. This involves also the pollinators community which ensures insect-pollinated plant reproduction in our natural environment and provides a great ecosystem service to mankind, particularly for food safety and human welfare. The aim of this study is two-fold: i) to produce a comprehensive update of the decline of pollinators at global scale and ii) to focus especially on the issue of pollinators disease transmission. In this research we argue that the cause of insect-pollinator decline is multi-factorial, including anthropogenic pressures such as land-use change (habitats loss, agricultural intensification…), climate change, pesticides and the spread of alien species and diseases. It also appears that the high prevalence of a broad range of insects and commercial use of pollinators are key drivers of pathogens transmission (virus, parasites …). However, the dynamics of pathogens transmission is still poorly known and, in turn, more scientific research must be performed to have a better insight of this issue. Finally, pollinators decline results from synergetic actions among these stress generators at different spatio-temporal levels emphasized by the globalization of commercial exchanges. [less ▲]

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