The Experts below are selected from a list of 459 Experts worldwide ranked by ideXlab platform
Georges Lognay - One of the best experts on this subject based on the ideXlab platform.
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validation of a fast gas chromatographic method for the study of semiochemical slow release formulations
Journal of Pharmaceutical and Biomedical Analysis, 2010Co-Authors: Stephanie Heuskin, Stephanie Lorge, Jean-paul Wathelet, Francois Verheggen, Eric Haubruge, Eric Rozet, Julien Farmakidis, Philippe Hubert, Georges LognayAbstract:The validation of a fast GC-FID analytical method for the quantitative determination of semiochemical sesquiterpenes (E-Beta-Farnesene and Beta-caryophyllene) to be used in an integrated pest management approach is described. Accuracy profiles using total error as decision criteria for validation were used to verify the overall accuracy of the method results within a well defined range of concentrations and to determine the lowest limit of quantification for each analyte. Furthermore it allowed to select a very simple and reliable regression model for calibration curve for the quantification of both analytes as well as to provide measurement uncertainty without any additional experiments. Finally, this validated method was used for the quantification of semiochemicals in slow release formulations. The goal was to verify the protection efficiency of alginate gel beads formulations against oxidation and degradation of sesquiterpenes. The results showed that the alginate beads are adequate slow release devices which protect the bio-active molecules during at least twenty days. (C) 2010 Elsevier B.V. All rights reserved.
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Validation of a fast gas chromatographic method for the study of semiochemical slow release formulations.
Journal of pharmaceutical and biomedical analysis, 2010Co-Authors: Stephanie Heuskin, Stephanie Lorge, Jean-paul Wathelet, Francois Verheggen, Eric Haubruge, Eric Rozet, Julien Farmakidis, Philippe Hubert, Georges LognayAbstract:The validation of a fast GC-FID analytical method for the quantitative determination of semiochemical sesquiterpenes (E-Beta-Farnesene and Beta-caryophyllene) to be used in an integrated pest management approach is described. Accuracy profiles using total error as decision criteria for validation were used to verify the overall accuracy of the method results within a well defined range of concentrations and to determine the lowest limit of quantification for each analyte. Furthermore it allowed to select a very simple and reliable regression model for calibration curve for the quantification of both analytes as well as to provide measurement uncertainty without any additional experiments. Finally, this validated method was used for the quantification of semiochemicals in slow release formulations. The goal was to verify the protection efficiency of alginate gel beads formulations against oxidation and degradation of sesquiterpenes. The results showed that the alginate beads are adequate slow release devices which protect the bio-active molecules during at least twenty days.
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Fast gas chromatography characterisation of purified semiochemicals from essential oils of Matricaria chamomilla L. (Asteraceae) and Nepeta cataria L. (Lamiaceae).
Journal of chromatography. A, 2008Co-Authors: Stephanie Heuskin, Jean-paul Wathelet, Francois Verheggen, Eric Haubruge, Quentin Capella, Bruno Godin, Pascal Leroy, Georges LognayAbstract:The chemical composition of Matricaria chamomilla L. and Nepeta cataria L. essential oils was determined by GC-MS on an apolar stationary phase by comparison of the characteristic fragmentation patterns with those of the Wiley 275L database. The GC-MS chromatograms were compared with those obtained by fast GC equipped with a direct resistively heated column (Ultra Fast Module 5% phenyl, 5 mx 0.1 mm, 0.1 microm film thickness). Analytical conditions were optimised to reach a good peak resolution (split ratio=1:100), with analysis time lower than 5 min versus 35-45 min required by conventional GC-MS. The fast chromatographic method was completely validated for the analysis of mono- and sesquiterpene compounds. Essential oils were then fractionated by column chromatography packed with silica gel. Three main fractions with high degree of purity in E-Beta-Farnesene were isolated from the oil of M. chamomilla. One fraction enriched in (Z,E)-nepetalactone and one enriched in Beta-caryophyllene were obtained from the oil of N. cataria. These semiochemical compounds could act as attractants of aphid's predators and parasitoids.
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Electrophysiological and Behavioral Responses of the Multicolored Asian Lady Beetle, Harmonia axyridis Pallas, to Sesquiterpene Semiochemicals
Journal of chemical ecology, 2007Co-Authors: Francois Verheggen, Stephanie Heuskin, Frederic Francis, Georges Lognay, Quentin Fagel, Eric HaubrugeAbstract:The role of two volatile sesquiterpenes, (E)-Beta-Farnesene and (-)-Beta-caryophyllene, in the chemical ecology of the multicolored Asian lady beetle, Harmonia axyridis Pallas, was investigated by using both electrophysiological and behavioral techniques. (E)-Beta-Farnesene is the major component of the alarm pheromone of most aphid species, which are preyed on by H. axyridis. (-)-Beta-Caryophyllene was previously isolated from the headspace volatiles above overwintering and aggregated H. axyridis females. These sesquiterpenes elicited significant electroantennogram (EAG) activity from both H. axyridis male and female antennae. In a four-arm olfactometer, male and female H. axyridis were highly attracted toward (E)-Beta-Farnesene, whereas only males were attracted to (-)-Beta-caryophyllene. In a bioassay technique that used a passively ventilated plastic box, both male and female H. axyridis aggregated in the (-)-Beta-caryophyllene-treated side of the box. These results support the potential usefulness of (E)-Beta-Farnesene and (-)-Beta-caryophyllene in push-pull strategies that use H. axyridis as a biological control agent in aphid-infested sites or to control this new urban pest in residential structures.
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role of e Beta Farnesene in systematic aphid prey location by episyrphus balteatus larvae diptera syrphidae
European Journal of Entomology, 2005Co-Authors: Frederic Francis, Georges Lognay, Thibau Marti, Eric HaubrugeAbstract:The foraging behaviour of beneficials such as aphidophagous predators depend largely on volatile compounds emitted by potential preys. Even if polyphagous predatory species are considered, all the potential preys are not systematically localised and accepted. In this work, chemical cues from different aphids and plants, each alone or in association, were studied to elucidate their role in prey location. Using a four-arm olfactometer, attraction of combinations of three aphid (Megoura viciae, Acyrthosiphon pisum and Aphis fabae) and one plant (Vicia faba) species for Episyrphus balteatus larvae was observed. Predatory hoverfly larvae were attracted by all tested stimuli in the presence of aphids, whatever the species. Whole or crushed aphids and also aphids on bean plant parts were attractive to syrphid larvae, but the host plant alone did not present any infochemical role for E. balteatus. Identifi- cation and quantification of the volatile releases from aphid and plant species, alone or in association, were performed using SPME and GC-MS methods. Aphid alarm pheromone, (E)-E-Farnesene, was found in the volatile pattern of each aphid and was tested for its role as an effective kairomone for the hoverfly.
Eric Haubruge - One of the best experts on this subject based on the ideXlab platform.
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validation of a fast gas chromatographic method for the study of semiochemical slow release formulations
Journal of Pharmaceutical and Biomedical Analysis, 2010Co-Authors: Stephanie Heuskin, Stephanie Lorge, Jean-paul Wathelet, Francois Verheggen, Eric Haubruge, Eric Rozet, Julien Farmakidis, Philippe Hubert, Georges LognayAbstract:The validation of a fast GC-FID analytical method for the quantitative determination of semiochemical sesquiterpenes (E-Beta-Farnesene and Beta-caryophyllene) to be used in an integrated pest management approach is described. Accuracy profiles using total error as decision criteria for validation were used to verify the overall accuracy of the method results within a well defined range of concentrations and to determine the lowest limit of quantification for each analyte. Furthermore it allowed to select a very simple and reliable regression model for calibration curve for the quantification of both analytes as well as to provide measurement uncertainty without any additional experiments. Finally, this validated method was used for the quantification of semiochemicals in slow release formulations. The goal was to verify the protection efficiency of alginate gel beads formulations against oxidation and degradation of sesquiterpenes. The results showed that the alginate beads are adequate slow release devices which protect the bio-active molecules during at least twenty days. (C) 2010 Elsevier B.V. All rights reserved.
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Validation of a fast gas chromatographic method for the study of semiochemical slow release formulations.
Journal of pharmaceutical and biomedical analysis, 2010Co-Authors: Stephanie Heuskin, Stephanie Lorge, Jean-paul Wathelet, Francois Verheggen, Eric Haubruge, Eric Rozet, Julien Farmakidis, Philippe Hubert, Georges LognayAbstract:The validation of a fast GC-FID analytical method for the quantitative determination of semiochemical sesquiterpenes (E-Beta-Farnesene and Beta-caryophyllene) to be used in an integrated pest management approach is described. Accuracy profiles using total error as decision criteria for validation were used to verify the overall accuracy of the method results within a well defined range of concentrations and to determine the lowest limit of quantification for each analyte. Furthermore it allowed to select a very simple and reliable regression model for calibration curve for the quantification of both analytes as well as to provide measurement uncertainty without any additional experiments. Finally, this validated method was used for the quantification of semiochemicals in slow release formulations. The goal was to verify the protection efficiency of alginate gel beads formulations against oxidation and degradation of sesquiterpenes. The results showed that the alginate beads are adequate slow release devices which protect the bio-active molecules during at least twenty days.
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Fast gas chromatography characterisation of purified semiochemicals from essential oils of Matricaria chamomilla L. (Asteraceae) and Nepeta cataria L. (Lamiaceae).
Journal of chromatography. A, 2008Co-Authors: Stephanie Heuskin, Jean-paul Wathelet, Francois Verheggen, Eric Haubruge, Quentin Capella, Bruno Godin, Pascal Leroy, Georges LognayAbstract:The chemical composition of Matricaria chamomilla L. and Nepeta cataria L. essential oils was determined by GC-MS on an apolar stationary phase by comparison of the characteristic fragmentation patterns with those of the Wiley 275L database. The GC-MS chromatograms were compared with those obtained by fast GC equipped with a direct resistively heated column (Ultra Fast Module 5% phenyl, 5 mx 0.1 mm, 0.1 microm film thickness). Analytical conditions were optimised to reach a good peak resolution (split ratio=1:100), with analysis time lower than 5 min versus 35-45 min required by conventional GC-MS. The fast chromatographic method was completely validated for the analysis of mono- and sesquiterpene compounds. Essential oils were then fractionated by column chromatography packed with silica gel. Three main fractions with high degree of purity in E-Beta-Farnesene were isolated from the oil of M. chamomilla. One fraction enriched in (Z,E)-nepetalactone and one enriched in Beta-caryophyllene were obtained from the oil of N. cataria. These semiochemical compounds could act as attractants of aphid's predators and parasitoids.
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What makes Episyrphus balteatus (Diptera: Syrphidae) oviposit on aphid infested tomato plants?
Communications in agricultural and applied biological sciences, 2008Co-Authors: Francois Verheggen, Jean-paul Wathelet, Quentin Capella, Eric HaubrugeAbstract:Under attack by insect pests, many plant species change their volatile chemical emissions to attract natural enemies. Most of the tomato (Lycopersicon sp., Solanaceae) varieties are subjected to infestation by molluscs and insects, including the generalist aphid Myzus persicae Sulzer (Homoptera, Aphididae). Episyrphus balteatus De Geer (Diptera: Syrphidae) is a generalist aphid predator that was here observed to lay eggs on M. persicae infested tomato but not on non-infested plants. In order to identify the volatile chemicals that guide the foraging and oviposition behaviour of E. balteatus, we collected and identified volatiles released in the headspace of both aphid infested and uninfested tomato plants by SPME-GC-MS. The identified chemicals were subsequently tested by electroantennography (EAG) on E. balteatus. Monoterpenes and sesquiterpenes were identified, the main volatile chemicals being Beta-phellandrene, 2-carene, alpha-phellandrene, 3-carene and o-pinene. Electrical depolarizations were observed for each tested monoterpene, with optimal responses ranging from -0.2 to -0.8 mV. Episyrphus balteatus antennae showed dose-response relationships towards all the active chemicals. (E)-Beta-Farnesene, the main component of the aphid alarm pheromone, was the only active sesquiterpene, and is presumed to act as an oviposition stimulus for E. balteotus.
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Electrophysiological and Behavioral Responses of the Multicolored Asian Lady Beetle, Harmonia axyridis Pallas, to Sesquiterpene Semiochemicals
Journal of chemical ecology, 2007Co-Authors: Francois Verheggen, Stephanie Heuskin, Frederic Francis, Georges Lognay, Quentin Fagel, Eric HaubrugeAbstract:The role of two volatile sesquiterpenes, (E)-Beta-Farnesene and (-)-Beta-caryophyllene, in the chemical ecology of the multicolored Asian lady beetle, Harmonia axyridis Pallas, was investigated by using both electrophysiological and behavioral techniques. (E)-Beta-Farnesene is the major component of the alarm pheromone of most aphid species, which are preyed on by H. axyridis. (-)-Beta-Caryophyllene was previously isolated from the headspace volatiles above overwintering and aggregated H. axyridis females. These sesquiterpenes elicited significant electroantennogram (EAG) activity from both H. axyridis male and female antennae. In a four-arm olfactometer, male and female H. axyridis were highly attracted toward (E)-Beta-Farnesene, whereas only males were attracted to (-)-Beta-caryophyllene. In a bioassay technique that used a passively ventilated plastic box, both male and female H. axyridis aggregated in the (-)-Beta-caryophyllene-treated side of the box. These results support the potential usefulness of (E)-Beta-Farnesene and (-)-Beta-caryophyllene in push-pull strategies that use H. axyridis as a biological control agent in aphid-infested sites or to control this new urban pest in residential structures.
Stephanie Heuskin - One of the best experts on this subject based on the ideXlab platform.
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validation of a fast gas chromatographic method for the study of semiochemical slow release formulations
Journal of Pharmaceutical and Biomedical Analysis, 2010Co-Authors: Stephanie Heuskin, Stephanie Lorge, Jean-paul Wathelet, Francois Verheggen, Eric Haubruge, Eric Rozet, Julien Farmakidis, Philippe Hubert, Georges LognayAbstract:The validation of a fast GC-FID analytical method for the quantitative determination of semiochemical sesquiterpenes (E-Beta-Farnesene and Beta-caryophyllene) to be used in an integrated pest management approach is described. Accuracy profiles using total error as decision criteria for validation were used to verify the overall accuracy of the method results within a well defined range of concentrations and to determine the lowest limit of quantification for each analyte. Furthermore it allowed to select a very simple and reliable regression model for calibration curve for the quantification of both analytes as well as to provide measurement uncertainty without any additional experiments. Finally, this validated method was used for the quantification of semiochemicals in slow release formulations. The goal was to verify the protection efficiency of alginate gel beads formulations against oxidation and degradation of sesquiterpenes. The results showed that the alginate beads are adequate slow release devices which protect the bio-active molecules during at least twenty days. (C) 2010 Elsevier B.V. All rights reserved.
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Validation of a fast gas chromatographic method for the study of semiochemical slow release formulations.
Journal of pharmaceutical and biomedical analysis, 2010Co-Authors: Stephanie Heuskin, Stephanie Lorge, Jean-paul Wathelet, Francois Verheggen, Eric Haubruge, Eric Rozet, Julien Farmakidis, Philippe Hubert, Georges LognayAbstract:The validation of a fast GC-FID analytical method for the quantitative determination of semiochemical sesquiterpenes (E-Beta-Farnesene and Beta-caryophyllene) to be used in an integrated pest management approach is described. Accuracy profiles using total error as decision criteria for validation were used to verify the overall accuracy of the method results within a well defined range of concentrations and to determine the lowest limit of quantification for each analyte. Furthermore it allowed to select a very simple and reliable regression model for calibration curve for the quantification of both analytes as well as to provide measurement uncertainty without any additional experiments. Finally, this validated method was used for the quantification of semiochemicals in slow release formulations. The goal was to verify the protection efficiency of alginate gel beads formulations against oxidation and degradation of sesquiterpenes. The results showed that the alginate beads are adequate slow release devices which protect the bio-active molecules during at least twenty days.
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Fast gas chromatography characterisation of purified semiochemicals from essential oils of Matricaria chamomilla L. (Asteraceae) and Nepeta cataria L. (Lamiaceae).
Journal of chromatography. A, 2008Co-Authors: Stephanie Heuskin, Jean-paul Wathelet, Francois Verheggen, Eric Haubruge, Quentin Capella, Bruno Godin, Pascal Leroy, Georges LognayAbstract:The chemical composition of Matricaria chamomilla L. and Nepeta cataria L. essential oils was determined by GC-MS on an apolar stationary phase by comparison of the characteristic fragmentation patterns with those of the Wiley 275L database. The GC-MS chromatograms were compared with those obtained by fast GC equipped with a direct resistively heated column (Ultra Fast Module 5% phenyl, 5 mx 0.1 mm, 0.1 microm film thickness). Analytical conditions were optimised to reach a good peak resolution (split ratio=1:100), with analysis time lower than 5 min versus 35-45 min required by conventional GC-MS. The fast chromatographic method was completely validated for the analysis of mono- and sesquiterpene compounds. Essential oils were then fractionated by column chromatography packed with silica gel. Three main fractions with high degree of purity in E-Beta-Farnesene were isolated from the oil of M. chamomilla. One fraction enriched in (Z,E)-nepetalactone and one enriched in Beta-caryophyllene were obtained from the oil of N. cataria. These semiochemical compounds could act as attractants of aphid's predators and parasitoids.
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Electrophysiological and Behavioral Responses of the Multicolored Asian Lady Beetle, Harmonia axyridis Pallas, to Sesquiterpene Semiochemicals
Journal of chemical ecology, 2007Co-Authors: Francois Verheggen, Stephanie Heuskin, Frederic Francis, Georges Lognay, Quentin Fagel, Eric HaubrugeAbstract:The role of two volatile sesquiterpenes, (E)-Beta-Farnesene and (-)-Beta-caryophyllene, in the chemical ecology of the multicolored Asian lady beetle, Harmonia axyridis Pallas, was investigated by using both electrophysiological and behavioral techniques. (E)-Beta-Farnesene is the major component of the alarm pheromone of most aphid species, which are preyed on by H. axyridis. (-)-Beta-Caryophyllene was previously isolated from the headspace volatiles above overwintering and aggregated H. axyridis females. These sesquiterpenes elicited significant electroantennogram (EAG) activity from both H. axyridis male and female antennae. In a four-arm olfactometer, male and female H. axyridis were highly attracted toward (E)-Beta-Farnesene, whereas only males were attracted to (-)-Beta-caryophyllene. In a bioassay technique that used a passively ventilated plastic box, both male and female H. axyridis aggregated in the (-)-Beta-caryophyllene-treated side of the box. These results support the potential usefulness of (E)-Beta-Farnesene and (-)-Beta-caryophyllene in push-pull strategies that use H. axyridis as a biological control agent in aphid-infested sites or to control this new urban pest in residential structures.
Francois Verheggen - One of the best experts on this subject based on the ideXlab platform.
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validation of a fast gas chromatographic method for the study of semiochemical slow release formulations
Journal of Pharmaceutical and Biomedical Analysis, 2010Co-Authors: Stephanie Heuskin, Stephanie Lorge, Jean-paul Wathelet, Francois Verheggen, Eric Haubruge, Eric Rozet, Julien Farmakidis, Philippe Hubert, Georges LognayAbstract:The validation of a fast GC-FID analytical method for the quantitative determination of semiochemical sesquiterpenes (E-Beta-Farnesene and Beta-caryophyllene) to be used in an integrated pest management approach is described. Accuracy profiles using total error as decision criteria for validation were used to verify the overall accuracy of the method results within a well defined range of concentrations and to determine the lowest limit of quantification for each analyte. Furthermore it allowed to select a very simple and reliable regression model for calibration curve for the quantification of both analytes as well as to provide measurement uncertainty without any additional experiments. Finally, this validated method was used for the quantification of semiochemicals in slow release formulations. The goal was to verify the protection efficiency of alginate gel beads formulations against oxidation and degradation of sesquiterpenes. The results showed that the alginate beads are adequate slow release devices which protect the bio-active molecules during at least twenty days. (C) 2010 Elsevier B.V. All rights reserved.
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Validation of a fast gas chromatographic method for the study of semiochemical slow release formulations.
Journal of pharmaceutical and biomedical analysis, 2010Co-Authors: Stephanie Heuskin, Stephanie Lorge, Jean-paul Wathelet, Francois Verheggen, Eric Haubruge, Eric Rozet, Julien Farmakidis, Philippe Hubert, Georges LognayAbstract:The validation of a fast GC-FID analytical method for the quantitative determination of semiochemical sesquiterpenes (E-Beta-Farnesene and Beta-caryophyllene) to be used in an integrated pest management approach is described. Accuracy profiles using total error as decision criteria for validation were used to verify the overall accuracy of the method results within a well defined range of concentrations and to determine the lowest limit of quantification for each analyte. Furthermore it allowed to select a very simple and reliable regression model for calibration curve for the quantification of both analytes as well as to provide measurement uncertainty without any additional experiments. Finally, this validated method was used for the quantification of semiochemicals in slow release formulations. The goal was to verify the protection efficiency of alginate gel beads formulations against oxidation and degradation of sesquiterpenes. The results showed that the alginate beads are adequate slow release devices which protect the bio-active molecules during at least twenty days.
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Fast gas chromatography characterisation of purified semiochemicals from essential oils of Matricaria chamomilla L. (Asteraceae) and Nepeta cataria L. (Lamiaceae).
Journal of chromatography. A, 2008Co-Authors: Stephanie Heuskin, Jean-paul Wathelet, Francois Verheggen, Eric Haubruge, Quentin Capella, Bruno Godin, Pascal Leroy, Georges LognayAbstract:The chemical composition of Matricaria chamomilla L. and Nepeta cataria L. essential oils was determined by GC-MS on an apolar stationary phase by comparison of the characteristic fragmentation patterns with those of the Wiley 275L database. The GC-MS chromatograms were compared with those obtained by fast GC equipped with a direct resistively heated column (Ultra Fast Module 5% phenyl, 5 mx 0.1 mm, 0.1 microm film thickness). Analytical conditions were optimised to reach a good peak resolution (split ratio=1:100), with analysis time lower than 5 min versus 35-45 min required by conventional GC-MS. The fast chromatographic method was completely validated for the analysis of mono- and sesquiterpene compounds. Essential oils were then fractionated by column chromatography packed with silica gel. Three main fractions with high degree of purity in E-Beta-Farnesene were isolated from the oil of M. chamomilla. One fraction enriched in (Z,E)-nepetalactone and one enriched in Beta-caryophyllene were obtained from the oil of N. cataria. These semiochemical compounds could act as attractants of aphid's predators and parasitoids.
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What makes Episyrphus balteatus (Diptera: Syrphidae) oviposit on aphid infested tomato plants?
Communications in agricultural and applied biological sciences, 2008Co-Authors: Francois Verheggen, Jean-paul Wathelet, Quentin Capella, Eric HaubrugeAbstract:Under attack by insect pests, many plant species change their volatile chemical emissions to attract natural enemies. Most of the tomato (Lycopersicon sp., Solanaceae) varieties are subjected to infestation by molluscs and insects, including the generalist aphid Myzus persicae Sulzer (Homoptera, Aphididae). Episyrphus balteatus De Geer (Diptera: Syrphidae) is a generalist aphid predator that was here observed to lay eggs on M. persicae infested tomato but not on non-infested plants. In order to identify the volatile chemicals that guide the foraging and oviposition behaviour of E. balteatus, we collected and identified volatiles released in the headspace of both aphid infested and uninfested tomato plants by SPME-GC-MS. The identified chemicals were subsequently tested by electroantennography (EAG) on E. balteatus. Monoterpenes and sesquiterpenes were identified, the main volatile chemicals being Beta-phellandrene, 2-carene, alpha-phellandrene, 3-carene and o-pinene. Electrical depolarizations were observed for each tested monoterpene, with optimal responses ranging from -0.2 to -0.8 mV. Episyrphus balteatus antennae showed dose-response relationships towards all the active chemicals. (E)-Beta-Farnesene, the main component of the aphid alarm pheromone, was the only active sesquiterpene, and is presumed to act as an oviposition stimulus for E. balteotus.
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Electrophysiological and Behavioral Responses of the Multicolored Asian Lady Beetle, Harmonia axyridis Pallas, to Sesquiterpene Semiochemicals
Journal of chemical ecology, 2007Co-Authors: Francois Verheggen, Stephanie Heuskin, Frederic Francis, Georges Lognay, Quentin Fagel, Eric HaubrugeAbstract:The role of two volatile sesquiterpenes, (E)-Beta-Farnesene and (-)-Beta-caryophyllene, in the chemical ecology of the multicolored Asian lady beetle, Harmonia axyridis Pallas, was investigated by using both electrophysiological and behavioral techniques. (E)-Beta-Farnesene is the major component of the alarm pheromone of most aphid species, which are preyed on by H. axyridis. (-)-Beta-Caryophyllene was previously isolated from the headspace volatiles above overwintering and aggregated H. axyridis females. These sesquiterpenes elicited significant electroantennogram (EAG) activity from both H. axyridis male and female antennae. In a four-arm olfactometer, male and female H. axyridis were highly attracted toward (E)-Beta-Farnesene, whereas only males were attracted to (-)-Beta-caryophyllene. In a bioassay technique that used a passively ventilated plastic box, both male and female H. axyridis aggregated in the (-)-Beta-caryophyllene-treated side of the box. These results support the potential usefulness of (E)-Beta-Farnesene and (-)-Beta-caryophyllene in push-pull strategies that use H. axyridis as a biological control agent in aphid-infested sites or to control this new urban pest in residential structures.
Jean-paul Wathelet - One of the best experts on this subject based on the ideXlab platform.
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validation of a fast gas chromatographic method for the study of semiochemical slow release formulations
Journal of Pharmaceutical and Biomedical Analysis, 2010Co-Authors: Stephanie Heuskin, Stephanie Lorge, Jean-paul Wathelet, Francois Verheggen, Eric Haubruge, Eric Rozet, Julien Farmakidis, Philippe Hubert, Georges LognayAbstract:The validation of a fast GC-FID analytical method for the quantitative determination of semiochemical sesquiterpenes (E-Beta-Farnesene and Beta-caryophyllene) to be used in an integrated pest management approach is described. Accuracy profiles using total error as decision criteria for validation were used to verify the overall accuracy of the method results within a well defined range of concentrations and to determine the lowest limit of quantification for each analyte. Furthermore it allowed to select a very simple and reliable regression model for calibration curve for the quantification of both analytes as well as to provide measurement uncertainty without any additional experiments. Finally, this validated method was used for the quantification of semiochemicals in slow release formulations. The goal was to verify the protection efficiency of alginate gel beads formulations against oxidation and degradation of sesquiterpenes. The results showed that the alginate beads are adequate slow release devices which protect the bio-active molecules during at least twenty days. (C) 2010 Elsevier B.V. All rights reserved.
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Validation of a fast gas chromatographic method for the study of semiochemical slow release formulations.
Journal of pharmaceutical and biomedical analysis, 2010Co-Authors: Stephanie Heuskin, Stephanie Lorge, Jean-paul Wathelet, Francois Verheggen, Eric Haubruge, Eric Rozet, Julien Farmakidis, Philippe Hubert, Georges LognayAbstract:The validation of a fast GC-FID analytical method for the quantitative determination of semiochemical sesquiterpenes (E-Beta-Farnesene and Beta-caryophyllene) to be used in an integrated pest management approach is described. Accuracy profiles using total error as decision criteria for validation were used to verify the overall accuracy of the method results within a well defined range of concentrations and to determine the lowest limit of quantification for each analyte. Furthermore it allowed to select a very simple and reliable regression model for calibration curve for the quantification of both analytes as well as to provide measurement uncertainty without any additional experiments. Finally, this validated method was used for the quantification of semiochemicals in slow release formulations. The goal was to verify the protection efficiency of alginate gel beads formulations against oxidation and degradation of sesquiterpenes. The results showed that the alginate beads are adequate slow release devices which protect the bio-active molecules during at least twenty days.
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Fast gas chromatography characterisation of purified semiochemicals from essential oils of Matricaria chamomilla L. (Asteraceae) and Nepeta cataria L. (Lamiaceae).
Journal of chromatography. A, 2008Co-Authors: Stephanie Heuskin, Jean-paul Wathelet, Francois Verheggen, Eric Haubruge, Quentin Capella, Bruno Godin, Pascal Leroy, Georges LognayAbstract:The chemical composition of Matricaria chamomilla L. and Nepeta cataria L. essential oils was determined by GC-MS on an apolar stationary phase by comparison of the characteristic fragmentation patterns with those of the Wiley 275L database. The GC-MS chromatograms were compared with those obtained by fast GC equipped with a direct resistively heated column (Ultra Fast Module 5% phenyl, 5 mx 0.1 mm, 0.1 microm film thickness). Analytical conditions were optimised to reach a good peak resolution (split ratio=1:100), with analysis time lower than 5 min versus 35-45 min required by conventional GC-MS. The fast chromatographic method was completely validated for the analysis of mono- and sesquiterpene compounds. Essential oils were then fractionated by column chromatography packed with silica gel. Three main fractions with high degree of purity in E-Beta-Farnesene were isolated from the oil of M. chamomilla. One fraction enriched in (Z,E)-nepetalactone and one enriched in Beta-caryophyllene were obtained from the oil of N. cataria. These semiochemical compounds could act as attractants of aphid's predators and parasitoids.
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What makes Episyrphus balteatus (Diptera: Syrphidae) oviposit on aphid infested tomato plants?
Communications in agricultural and applied biological sciences, 2008Co-Authors: Francois Verheggen, Jean-paul Wathelet, Quentin Capella, Eric HaubrugeAbstract:Under attack by insect pests, many plant species change their volatile chemical emissions to attract natural enemies. Most of the tomato (Lycopersicon sp., Solanaceae) varieties are subjected to infestation by molluscs and insects, including the generalist aphid Myzus persicae Sulzer (Homoptera, Aphididae). Episyrphus balteatus De Geer (Diptera: Syrphidae) is a generalist aphid predator that was here observed to lay eggs on M. persicae infested tomato but not on non-infested plants. In order to identify the volatile chemicals that guide the foraging and oviposition behaviour of E. balteatus, we collected and identified volatiles released in the headspace of both aphid infested and uninfested tomato plants by SPME-GC-MS. The identified chemicals were subsequently tested by electroantennography (EAG) on E. balteatus. Monoterpenes and sesquiterpenes were identified, the main volatile chemicals being Beta-phellandrene, 2-carene, alpha-phellandrene, 3-carene and o-pinene. Electrical depolarizations were observed for each tested monoterpene, with optimal responses ranging from -0.2 to -0.8 mV. Episyrphus balteatus antennae showed dose-response relationships towards all the active chemicals. (E)-Beta-Farnesene, the main component of the aphid alarm pheromone, was the only active sesquiterpene, and is presumed to act as an oviposition stimulus for E. balteotus.