References of "Heuskin, Stéphanie"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailQuantification of four Isoflavones in Forages with UPLC®-MS/MS, using the Box-Behnken Experimental Design to Optimize Sample Preparation
Daems, Frédéric ULg; Romnee, Jean-Michel; Rasse, Catherine et al

in Chromatographia (in press)

A performant method for the simultaneous quantification of daidzein, genistein, formononetin and biochanin A in forages using an UPLC®-MS/MS was developed and fully validated. The ultrasound-assisted ... [more ▼]

A performant method for the simultaneous quantification of daidzein, genistein, formononetin and biochanin A in forages using an UPLC®-MS/MS was developed and fully validated. The ultrasound-assisted extraction and enzymatic hydrolysis used in the sample preparation step were optimized using the Box-Behnken experimental design. The optimal extraction conditions used for a representative mix of forage plants were 80°C, 10 min and 55% methanol, and for hydrolysis they were 20°C, 18 h and pH=6. The chromatographic separation was achieved using an Acquity® UPLC® HSS T3 column, with a water/methanol linear gradient containing 0.01% of formic acid at a 0.55 mL min-1 flow rate. The four isoflavones were detected by ESI mass spectrometry in positive ion MRM mode. The method allows high throughput analyses of samples and showed an adequate linear regression model for all isoflavones over a range from 5 to 125 ng mL-1. There was good intra- and inter-day precision (≤ 8.2% and ≤ 7.6%) and accuracy (≤ 11.4% and ≤ 7.1%). The recovery rates were in an acceptable range of 70-120%, except for biochanin A, where the rate was about 50%. Good method repeatability was also observed, and there was no matrix effect or carry-over problem. The sample extracts were stable for at least 6 days of storage at -21°C and 6°C. The method proved to be sensitive, precise and accurate for discriminating a wide variety of forages likely to be grazed by ruminants according to their isoflavone content and to observe the impact storage process on isoflavone content in forages. [less ▲]

Detailed reference viewed: 43 (4 ULg)
Full Text
Peer Reviewed
See detailInfluence of the secondary endosymbiont Serratia Symbiotica on the resistance to the parasitism in the aphid Acyrthosiphon pisum
Attia, Sabrine; Foray, Vincent; Louâpre, Philippe et al

in Journal of Entomology and Zoology Studies (in press)

Aphids have an obligate association with the primary symbiont Buchnera aphidicola and is known to affect aphid fitness. Aphids commonly harbour other facultative bacterial endosymbionts and may benefit ... [more ▼]

Aphids have an obligate association with the primary symbiont Buchnera aphidicola and is known to affect aphid fitness. Aphids commonly harbour other facultative bacterial endosymbionts and may benefit from their presence through increased resistance to parasitoids [1]. Present results suggest that the ability of hosts to defend against natural enemies depend not only on the presence of symbionts but also on the host genotype. Aphids represent a complex micro-environment for the parasitoid larvae and both the aphid physiology and endosymbiont influence their survival until mummification. [less ▲]

Detailed reference viewed: 87 (5 ULg)
Full Text
See detailCan tropical basil be integrated in vegetable crop pest management?
Yarou, Boni Barthélémy ULg; Verheggen, François ULg; Heuskin, Stéphanie ULg et al

Poster (2016, May 17)

To address human and environmental health issues related to the use of synthetic pesticides, it is important to explore other ecological pest management approaches. Within this context, a study was ... [more ▼]

To address human and environmental health issues related to the use of synthetic pesticides, it is important to explore other ecological pest management approaches. Within this context, a study was conducted to evaluate the toxic and repellent effect of Ocimum gratissimum L. (Lamiaceae) on Myzus persicae S. (Aphididae). The toxicity of O. gratissimum essential oil (EO) was evaluated on M. persicae comparing 3 concentrations (0.001%; 0.01% and 0.1%) to a control (15% sucrose). Mortality rate and fecundity were assessed for each concentration. The observations were made daily, for 4 days, on 12 replicates per treatment. To test the repellent effect of O. gratissimum plants, 2 treatments were compared: a group of 8 Amaranthus cruentus L. (Amaranthaceae) plants with 1 plant of O. gratissimum in the middle and a group of 9 A. cruentus plants (control). The distribution of aphids was analyzed 12 days after the middle plant infestation (20 aphids per plant) for each treatment (6 replicates per treatment). O. gratissimum EO was found toxic from a concentration of 0.01%, with a mortality rate of 34% versus 12% for the control ; The fecundity felt from 30 larvae after 4 days (control) to 15 larvae for the 3 doses of the EO. The analysis with the generalized linear mixed model with Poisson error distribution followed by Turkey test (5 %) showed that EO is significantly more toxic than the control, both for mortality and fecundity (p <0.001). In association test, the population of M. persicae (15 aphids per plant) was significantly (p<0,001) lower when A. cruentus plants was associated with O. gratissimum plant than with the control (22 aphids per plant). Furthermore, the population increases gradually as one moves away from the infestation point in association test whereas it decreases in the control. With regards to these results, it appears that O. gratissimum has biocide effects on M. persicae. This plant may be used in an integrated pest management strategy in the production of vegetable to reduce the use of synthetic pesticides and avoid chemicals residues. [less ▲]

Detailed reference viewed: 13 (2 ULg)
See detailDevelopment of a semiochemical-based control method against the walnut husk fly
Sarles, Landry ULg; Heuskin, Stéphanie ULg; Verheaghe, Agnès et al

Conference (2016, May 17)

Detailed reference viewed: 8 (1 ULg)
Full Text
Peer Reviewed
See detailAnalytical methods used to quantify isoflavones in cow's milk: a review
Daems, Frédéric ULg; Romnee, Jean-Michel; Heuskin, Stéphanie ULg et al

in Dairy Science and Technology (2016)

This paper provides an update and comprehensive review of the analytical methods used for quantifying isoflavones and their metabolites in cow’s milk. Isoflavones are secondary plant metabolites that are ... [more ▼]

This paper provides an update and comprehensive review of the analytical methods used for quantifying isoflavones and their metabolites in cow’s milk. Isoflavones are secondary plant metabolites that are similar to 17 β-estradiol in chemical structure. They form one of the most common categories of phytoestrogens. Numerous health benefits have been attributed to isoflavones, but many of these compounds are also considered to be endocrine disruptors, with adverse effects on health. These contradictory trends offer an attractive prospect for future research, and therefore, sensitive and reliable analytical methods are required to clarify various issues about isoflavones. For this review, a structured methodology was used to select 26 relevant articles published between 2005 and 2015 from the Scopus and CAB Abstract databases. The review discusses individual steps of the analytical procedures described in these articles, including sample preparation, instrumental analysis and validation. The most commonly used analytical procedure is sample preparation involving liquid-liquid extraction and an enzymatic hydrolysis step followed by liquid chromatography with mass spectrometry analysis. Currently, however, there is no standardized procedure for the sample preparation and analysis of isoflavones in milk. [less ▲]

Detailed reference viewed: 26 (12 ULg)
Full Text
Peer Reviewed
See detailChemical composition of essential oils and floral waters of Mentha longifolia (L.) Huds. from Senegal
Diop, Serigne Mbacké; Guèye, Momar Talla; Ndiaye, Ibrahima et al

in American Journal of Essential Oils and Natural Products (2016), 4(1), 46-49

Essential oils of Mentha longifolia from Senegal were extracted from fresh plants and dried plants in the shade for 7 days. The yields were of 0.39 and 0.32% in the fresh and dried plants respectively ... [more ▼]

Essential oils of Mentha longifolia from Senegal were extracted from fresh plants and dried plants in the shade for 7 days. The yields were of 0.39 and 0.32% in the fresh and dried plants respectively. Analysis of the essential oils, floral waters and the assay of pulegone were carried out by GC/FID and GC/MS. The major compounds identified in the oils were pulegone (52.0 and 42.4%), menthone (14.3 and 21.2%), 1, 8-cineole (13.1 and 11.4%) and isomenthone (9.0 and 13.2%) in the fresh and dried plants, respectively. Analyses revealed that floral waters were also characterized by the same major compounds as essential oils but at different rates. In these floral waters, pulegone constituted 60.2 and 47.0%, 1,8- cineole 7.9 and 19.6%, isomenthone 7.2 and 10.7%, menthone 6.4 and 9.2%, chrysanthenone 6.4 and 3.2% and α-terpineol 3.0 and 2.7% in the fresh and dried plants, respectively. The assay results of pulegone, a hepatotoxic compound, have shown very high levels (444.6 and 393.3mg/g) in both fresh and dried plants. [less ▲]

Detailed reference viewed: 27 (1 ULg)
Full Text
Peer Reviewed
See detailInsecticidal activity of Lavandula angustifolia Mill. against the pea aphid Acyrtosiphum pisum
Attia, Sabrine; Lognay, Georges ULg; Heuskin, Stéphanie ULg et al

in Journal of Entomology and Zoology Studies (2016), 4(1), 118-122

The essential oil of Lavandula angustifolia was investigated for its biocide activity against Acyrtosiphum pisum by fumigation. The oil was characterised by GC-MS revealing that linalool was the most ... [more ▼]

The essential oil of Lavandula angustifolia was investigated for its biocide activity against Acyrtosiphum pisum by fumigation. The oil was characterised by GC-MS revealing that linalool was the most abundant component (38.57%), followed by linalyl acetate (29.95%), 1,8-cineole (13,66%), camphor (13,13%), -pinene (3,14%) and terpinene-4-ol (1,54%). The Mortality was measured upon treatment with oil concentrations ranging from 5 to 25 µl.l-1 of air. The mortality of aphids increased with oil concentration and LC50 values were determined to be 11.2 µl.l-1 of air. The full mixture was also prepared and toxicity was compared with individual constituents. The results showed that the presence of all constituents were necessary to equal the toxicity of the natural oils L. angustifolia oil can provide valuable pesticide activity with significantly lower LC50 values [less ▲]

Detailed reference viewed: 43 (8 ULg)
Full Text
Peer Reviewed
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 ▲]

Detailed reference viewed: 43 (7 ULg)
Full Text
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 ▲]

Detailed reference viewed: 69 (10 ULg)
Full Text
Peer Reviewed
See detailA PHEROMONE TRAP MONITORING SYSTEM FOR THE SADDLE GALL MIDGE, Haplodiplosis marginata (von Roser) (DIPTERA: CECIDOMYIIDAE)
Censier, Florence ULg; Heuskin, Stéphanie ULg; SAN MARTIN Y GOMEZ, Gilles et al

in Crop Protection (2015), 80

Outbreaks of saddle gall midge, Haplodiplosis marginata (von Roser) (Diptera: Cecidomyiidae) have been reported in Belgium and other European countries since 2010. Because of the sporadic nature of this ... [more ▼]

Outbreaks of saddle gall midge, Haplodiplosis marginata (von Roser) (Diptera: Cecidomyiidae) have been reported in Belgium and other European countries since 2010. Because of the sporadic nature of this pest, which can sometimes be very harmful to cereal crops, an effective monitoring tool is required, both to determine the optimal timing for insecticide applications, and to understand the enigmatic population dynamics of this insect. Following the recent identification of the major sex pheromone component of the saddle gall midge, non-2-yl butanoate, a slow-release dispenser was developed using rubber septa. The release rates of 5 mg and 10 mg-loaded dispensers were initially measured under laboratory conditions, and their effectiveness in terms of pheromone loading and use duration was assessed in the field. The experiments showed that sticky traps baited with 5 mg pheromone-loaded rubber dispensers, renewed every 6 weeks, are suitable for accurately monitoring male H. marginata flights. [less ▲]

Detailed reference viewed: 61 (23 ULg)
See detailComment évaluer un arôme: approche analytique
Heuskin, Stéphanie ULg

Scientific conference (2015, October)

Detailed reference viewed: 14 (0 ULg)
Full Text
See detailDoes combining a wheat and pea mixture with methyl salicylate reduces aphid populations in both crops?
Chevalier Mendes Lopes, Thomas ULg; Fassotte, Bérénice ULg; Hatt, Séverin ULg 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 ▲]

Detailed reference viewed: 50 (14 ULg)
Full Text
Peer Reviewed
See detailKin recognition and inbreeding avoidance in a butterfly
Fischer; Karl, Isabell; Heuskin, Stéphanie ULg et al

in Ethology (2015), 121

Detailed reference viewed: 51 (2 ULg)
Peer Reviewed
See detailEfficiency of pheromone-based formulations against phytophagous pests
Fassotte, Bérénice ULg; Vandereycken, Axel ULg; Chevalier Mendes Lopes, Thomas ULg et al

Conference (2015, May 19)

Innovative integrated pest management methods are needed to overcome market withdrawal of synthetic pesticides. Therefore, the identification of environment-friendly bio-products carrying direct or ... [more ▼]

Innovative integrated pest management methods are needed to overcome market withdrawal of synthetic pesticides. Therefore, the identification of environment-friendly bio-products carrying direct or indirect biocide activity is one promising alternative option. Our researches focus on the identification of appropriate formulations releasing volatile organic compounds that are attractant for natural enemies of insect pests. However, the elaboration of slow-release devices that ensure stable and controlled release of active volatile compounds is quite challenging. Here, we developed a formulation based on E-β-farnesene and (-)-β-caryophyllene, these two semiochemicals having strong attractive potential on aphid natural enemies including lady beetles and hoverflies. Both compounds were encapsulated together in alginate gel beads. The blend efficiency was first evaluated through laboratory assays, and then in wheat and broad bean fields, by considering the abundance and diversity of aphids and their natural enemies. [less ▲]

Detailed reference viewed: 71 (12 ULg)
Full Text
See detailFood Compounds from Meadow Grasshoppers
Paul, Aman ULg; Frederich, Michel ULg; Uyttenbroeck, Roel ULg et al

Poster (2015, March 15)

Eating insects as food, particularly grasshopper is practiced in many cultures throughout the world. Meadow grasshopper (Chorthippus parallelus) is commonly found in Europe and some part of Asia. It is ... [more ▼]

Eating insects as food, particularly grasshopper is practiced in many cultures throughout the world. Meadow grasshopper (Chorthippus parallelus) is commonly found in Europe and some part of Asia. It is already known that grasshoppers of Chorthippus species are consumed as food in countries such as Thailand. With the aim of evaluating the nutritional potential of this insect species the proximate nutritional composition of grasshoppers caught from the local fields was realized. Besides this, the fatty acid profile of extracted lipids, amino acid profile and mineral composition of the insect was also revealed. Results suggest that meadow grasshopper is an excellent source of protein and essential amino acids. Lipids extracted from the grasshopper have an interesting fatty acid composition. Also the grasshopper contains some minerals that are important for body. With such protein content, amino acid profile, fatty acid profile of the lipids and mineral content this grasshopper species could present an interesting alternate to conventional protein sources. [less ▲]

Detailed reference viewed: 93 (27 ULg)
Full Text
Peer Reviewed
See detailAn analysis of potential resistance of the phytophagous mite, Tetranychus urticae Koch (Acari: Tetranychidae) to four botanical pesticides
Attia, Sabrine; Lebdi, KL; Heuskin, Stéphanie ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2015), 19(3), 232-238

Description of the subject. Synthetic acaricides have been widely used to manage Tetranychus urticae. Due to the excessive use of biocide and the associated problems of pesticide resistance and ... [more ▼]

Description of the subject. Synthetic acaricides have been widely used to manage Tetranychus urticae. Due to the excessive use of biocide and the associated problems of pesticide resistance and environmental pollution, there is an increasing demand for sustainable, environmentally-friendly control methods. Among the current alternative strategies aimed at decreasing the pest populations, the pesticides based on plant extracts are currently one of the most promising methods. Essential oils with acaricidal properties have been categorized as green pesticides because they are biodegradable and predominantly non-toxic to vertebrates. Objectives. With an aim to reduce the use of synthetic pesticides, they represent a promising approach for eco-chemical control of mites. Method. The aim of the present work was to analyze the risk of resistance emergence of T. urticae to repeated treatments with four plant extracts: Deverra scoparia Coss. & Durieu (Araliales: Apiaceae), Hertia cheirifolia (L.) Kuntze (Asterales: Ateraceae), Santolina africana Jord. & Fourr. (Asterales: Asteraceae) essential oils and garlic distillate Allium sativum L. (Asparagales: Alliaceae) after 20 generations. Results. Repeated treatments with S. africana essential oil during 20 generations did not provoke an emergence of resistance while a low development of resistance was observed with H. cheirifolia, A. sativum and D. scoparia extracts. Conclusions. The efficacy of these extracts against the two spotted spider mite and their low development of resistance make them a promising use for pest management. [less ▲]

Detailed reference viewed: 57 (7 ULg)
Full Text
See detail10. Perspectives - 1. La Lutte contre les pucerons grâce aux odeurs: développement d'une formulation phéromonale
Fassotte, Bérénice ULg; Vandereycken, Axel ULg; Chevalier Mendes Lopes, Thomas ULg et al

in Watillon, Bernard; Bodson, Bernard (Eds.) Livre Blanc Céréales (2015, February 25)

Detailed reference viewed: 44 (12 ULg)
Full Text
Peer Reviewed
See detailMyzus persicae feeding on water stressed Arabidopsis affects the emission profile of plant volatile organic compounds
Truong, Dieu-Hien; Delaplace, Pierre ULg; Brostaux, Yves ULg et al

in Journal of Environment and Ecology (2014), 5(2),

Emissions of volatile organic compounds (VOCs) by water-controlled or water-stressed Arabidopsis thaliana infested or not infested with Myzus persicae were evaluated by headspace solid phase ... [more ▼]

Emissions of volatile organic compounds (VOCs) by water-controlled or water-stressed Arabidopsis thaliana infested or not infested with Myzus persicae were evaluated by headspace solid phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). The infestations were maintained for 0–24 h, 24–48 h, and 48–72 h, and the emission profile for each time period was determined. Under these controlled conditions, the proportion of 4-methylpentyl isothiocyanate and dimethyl disulfide emitted by aphid-infested, water-stressed Arabidopsis was greater than that for aphid-infested water-controlled Arabidopsis over the 48–72 h sampling period. The proportion of terpene emitted by aphid-infested water-stressed plants also significantly increased compared with the other treatments over the three assayed sampling periods. In contrast, the proportion of 2-ethylhexanal (the only detected aldehyde) and ketones for the water-controlled plants generally remained high following aphid infestation. Taken together, these original data ascertain that abiotic factors can greatly interact to biotic stresses to alter the VOC emission profiles of plants. [less ▲]

Detailed reference viewed: 53 (11 ULg)