Do root-emitted volatile organic compounds attract wireworms?Barsics, Fanny ; Latine, Rémi ; Gfeller, Aurélie et alin Communications in Agricultural and Applied Biological Sciences (in press) Wireworms are the soil dwelling larvae of click beetles (Coleoptera: Elateridae). Their importance as crop pests increases since the efficient chemical means to control them cannot be considered anymore ... [more ▼] Wireworms are the soil dwelling larvae of click beetles (Coleoptera: Elateridae). Their importance as crop pests increases since the efficient chemical means to control them cannot be considered anymore. Therefore, many integrated pest management strategies have been investigated in the past few years. Most of them rely on the understanding of the ecology of the click beetles during their whole life cycle. We focus our work on the chemical ecology of wireworms, more precisely on the root-emitted volatile organic compounds (VOCs) that might intervene in the food-searching process of the larvae by helping them to find a suitable host-plant or by acting as key factors in the belowground defence mechanism of the plant. Here, we present our first results of dual-choice orientation tests in olfactometric pipes. Wireworms (Agriotes sordidus Illiger) were submitted individually to a variety of olfactory baits ranging from entire barley roots (Hordeum vulgare L. var. Quench) to isolated VOCs identified as part of the emitting profile. The latter was described thanks to HS-SPME samplings and GC-MS analysis, for roots grown in the exact same conditions as for the olfactometric experimentations with entire roots. Most of the experimentations gave significant results. When confronted to volatiles emitted by entire roots, wireworms significantly orientated towards the bait (χ²-goodness-of-fit test, χ²=8, P-value=0.005). This result allowed us to follow up with the same device and to progressively vary the nature of the baits. Our protocol should be used for other plant-wireworm species combinations. Our results should be taken into account in varietal selection, in crop rotation, or in trapping systems aiming at the reduction of the populations of wireworms. [less ▲] Detailed reference viewed: 60 (26 ULg) Analysis of the diastereoisomers of alliin by HPLCDETHIER, Bérénice ; Laloux, Morgan ; et alin Talanta (2012), 101 Garlic has been known for its therapeutic effects for centuries and is used worldwide as a functional food. The concentration of the active molecules could be enhanced by a better knowledge of their ... [more ▼] Garlic has been known for its therapeutic effects for centuries and is used worldwide as a functional food. The concentration of the active molecules could be enhanced by a better knowledge of their biosynthesis. The precursor of these compounds, alliin (a sulfur amino-acid) has been obtained by chemical synthesis. However, this synthesis route also leads to a diastereoisomer as co-product. This work describes the development of an analytical method which allows the separation and quantification of the two diastereoisomers in order to determine in which proportion the natural form can be produced. The HPLC method which was optimized and validated by accuracy profile exploits an original stationary phase consisting of porous graphitic carbon (PGC). Furthermore, the developped method was used to separate the diastereoisomers of methiin, another garlic cysteine sulfoxide, and to analyse and aqueous extract of garlic. The ability to quantify the amount of natural alliin is valuable for further work on garlic molecules and their application for health protection. [less ▲] Detailed reference viewed: 54 (19 ULg) Do root-emitted volatile organic compounds interact with wireworms?Barsics, Fanny ; Gfeller, Aurélie ; Laloux, Morgan et alScientific conference (2012, May 22) Wireworms are the soil dwelling larvae of click beetles (Coleoptera: Elateridae). Their importance as crop pests increases since the efficient chemical means to control them cannot be considered anymore ... [more ▼] Wireworms are the soil dwelling larvae of click beetles (Coleoptera: Elateridae). Their importance as crop pests increases since the efficient chemical means to control them cannot be considered anymore. Therefore, many integrated pest management strategies have been investigated in the past few years. Most of them rely on the understanding of the ecology of the click beetles during their whole life cycle. We focus our work on the chemical ecology of wireworms, more precisely on the root-emitted volatile organic compounds (VOCs) that might intervene in the food-searching process of the larvae by helping them to find a suitable host-plant or by acting as key factors in the belowground defence mechanism of the plant. Here, we present our first results of dual-choice orientation tests in olfactometric pipes. Wireworms (Agriotes sordidus Illiger) were submitted individually to a variety of olfactory baits ranging from entire barley roots (Hordeum vulgare L. var. Quench) to isolated VOCs identified as part of the emitting profile. The latter was described thanks to HS-SPME samplings and GC-MS analysis, for roots grown in the exact same conditions as for the olfactometric experimentations with entire roots. Most of the experimentations gave significant results. When confronted to volatiles emitted by entire roots, wireworms significantly orientated towards the bait (χ²-goodness-of-fit test, χ²=8, P-value=0.005). This result allowed us to follow up with the same device and to progressively vary the nature of the baits. Our protocol should be used for other plant-wireworm species combinations. Our results should be taken into account in varietal selection, in crop rotation, or in trapping systems aiming at the reduction of the populations of wireworms. [less ▲] Detailed reference viewed: 40 (8 ULg) Development of a headspace solid-phase microextraction method coupled to gas chromatography (HS-SPME GC-MS) to capture and analyze the volatile organic compounds emitted by barley roots (Hordeum vulgare cv. Quench)Laloux, Morgan ; ; Fauconnier, Marie-Laure et alPoster (2012, February 10) Detailed reference viewed: 14 (1 ULg) Identification and quantification of VOCs emitted by the roots of barley (Hordeum vulgare cv. Quench) aged from 21 days by headspace solid-phase microextraction coupled to gas chromatography (HS-SPME GC-MS)Laloux, Morgan ; Fauconnier, Marie-Laure ; Wathelet, Jean-Paul et alPoster (2012, February 10) Detailed reference viewed: 12 (3 ULg) A new HPLC method to quantify alliin, the major sulfur compound in garlicDETHIER, Bérénice ; Laloux, Morgan ; et alPoster (2012, February 10) Garlic is recognized for centuries for its health benefits, mostly linked to its sulfur- components. Among the products extracted from the cloves, alliin retained our attention. Alliin was synthesized ... [more ▼] Garlic is recognized for centuries for its health benefits, mostly linked to its sulfur- components. Among the products extracted from the cloves, alliin retained our attention. Alliin was synthesized. This process leads to two stereoisomers. Their HPLC separation was the aim of this work. The method described in the literature (amino column, detection at 210 nm) showed a resolution of 1,1 between the isomers. A second method was developed: the stationary phase was porous graphitic carbon and a water-ACN gradient was used for the elution. It provided a resolution of 3,2, was shorter and underwent the validation process. The method leads to satisfying results. The separation is excellent, and the validation criteria are fulfilled. This may be valuable for future research on garlic. [less ▲] Detailed reference viewed: 31 (8 ULg) Mise au point d’une méthode de capture et d’analyse des molécules organiques émises par les racines d’orge: la micro-extraction sur phase solide en espace de tête couplée à la chromatographie en phase gazeuse (HS-SPME GC-MS)Laloux, Morgan ; Kati, Djamel Edine ; Fauconnier, Marie-Laure et alPoster (2011, October 13) Detailed reference viewed: 25 (5 ULg) Les volatils racinaires de l’orge : un langage souterrain ?Barsics, Fanny ; Gfeller, Aurélie ; Fauconnier, Marie-Laure et alScientific conference (2011, October 13) Cette présentation résume les avancées du projet Rhizovol après une année de travaux de recherche. Detailed reference viewed: 57 (28 ULg) |
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