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Stefano Colazza - One of the best experts on this subject based on the ideXlab platform.
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lures for red palm weevil trapping systems aggregation pheromone and synthetic Kairomone
Pest Management Science, 2017Co-Authors: Sandra Vacas, Stefano Colazza, Ourania Melita, Antonios Michaelakis, Panagiotis G Milonas, R L Minuz, Paola Riolo, Mohamed Kamal Abbass, Paolo Lo Bue, Ezio PeriAbstract:BACKGROUND The optimisation of the lure is essential for the implementation of trapping systems to control insect pests. In this work, the response of the red palm weevil (RPW), Rhynchophorus ferrugineus Olivier, to increasing emission rates of its aggregation pheromone (ferrugineol) and the efficacy of a convenient synthetic Kairomone based on fermentation odours (ethyl acetate and ethanol) have been evaluated in different years and locations along the Mediterranean basin. RESULTS In general, although capture data and emission had noticeable variability among locations, significantly fewer RPW were captured in pyramidal Picusan® traps with the lowest ferrugineol emission rates tested (0.6–3.8 mg day−1). Captures increased rapidly with ferrugineol emission up to 4–5 mg day−1; then, higher emission rates did not improve or reduce captures, up to the highest emission rate tested of 50.9 mg day−1. Thus, there is no evidence of an optimum release rate corresponding to a maximum of RPW catches. Traps baited with the synthetic Kairomone (1:3 ethyl acetate/ethanol) captured 1.4–2.2 times more total weevils than traps baited only with ferrugineol. Moreover, in most of the locations, the synthetic blend was at least as effective as the local coattractants used (plant material + molasses). CONCLUSIONS Ferrugineol emission rate can vary in a wide range without significantly affecting RPW response. Coattractants based on fermenting compounds, ethyl acetate and ethanol, are able to improve the attractant level of ferrugineol and could be employed to replace non-standardised natural Kairomones in RPW trapping systems after further optimisation of their proportions and doses. © 2016 Society of Chemical Industry
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behavioral and chemical investigations of contact Kairomones released by the mud dauber wasp trypoxylon politum a host of the parasitoid melittobia digitata
Journal of Chemical Ecology, 2011Co-Authors: Jorge M Gonzalez, Antonino Cusumano, Stefano Colazza, Bradleich S VinsonAbstract:Contact Kairomones from the host mud dauber wasp Trypoxylon politum Say (Hymenoptera: Crabronidae) that mediate behavioral responses of its ectoparasitoid Melittobia digitata Dahms (Hymenoptera: Eulophidae) were investigated. Chemical residues from host by-products, the cocoon, and the meconium, induced arrestment behavior of macropterous female parasitoids, while those from the host stage attacked, i.e., the prepupa, did not. Melittobia digitata response to polar and apolar extracts of host by-products indicated Kairomone(s) solubility mainly in hexane. GC and GC/MS analysis of cocoon and meconium apolar extracts revealed a mixture of linear carboxylic acids from C6 to C18, and both extracts contained almost identical compounds. When a reconstructed blend of host by-product carboxylic acids was tested, M. digitata females showed only a weak response, thus suggesting that other unidentified compounds present in small quantities also may be involved. Melittobia digitata’s response to contact Kairomones was innate and not affected by previous host exposure experience. Our results provide evidence of contact Kairomone exploitation in the genus Melittobia. The ecological significance of these findings in the host selection process of M. digitata is discussed.
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Host Kairomone learning and foraging success in an egg parasitoid: a simulation model
Ecological Entomology, 2009Co-Authors: Guillaume Dauphin, Ezio Peri, Stefano Colazza, Patrick Coquillard, Eric WajnbergAbstract:Trissolcus basalis (Wollaston) (Hymenoptera: Scelionidae) is an egg parasitoid that recognises chemical residues left by its host the green stink bug Nezara viridula (L.) (Heteroptera: Pentatomidae) as Kairomone signals, enabling it to find egg masses in which to lay eggs. 2. Kairomones are usually present as patches deposited by N. viridula females, and recent results (Peri et al. , Journal of Experimental Biology , 209 , 3629 - 3635, 2006) indicated that females of T. basalis are able to learn the features of their foraging environment and to adjust accordingly the amount of time spent on the patches of Kairomones they are visiting, depending on whether or not host eggs are found. 3. In order to assess the impact of this learning ability, a Monte Carlo, spatially explicit and individual-based simulation model was built to quantify the foraging efficiency of T. basalis females in environments with different levels of host abundance and distribution. In all cases, the present study compared the foraging efficiency of simulated T. basalis females having the ability to learn with those lacking this ability. 4. Learning females always visited a higher number of Kairomone patches and attacked a higher number of hosts than non-learning females, especially when there was a high density of Kairomone patches in the environment. 5. Learning ability globally appears to allow the maintenance of efficient foraging success, especially when there is a low probability for the Kairomone patches to contain discoverable hosts. 6. The increase in foraging efficiency for learning females appears to depend on the characteristics of the habitat in which they are foraging. Results thus suggest that significant variation in learning ability is likely to occur in natural wasp populations facing different environments with different host spatial distributions.
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The Egg Parasitoid Trissolcus basalis uses n-nonadecane, a Cuticular Hydrocarbon from its Stink Bug Host Nezara viridula, to Discriminate Between Female and Male Hosts
Journal of Chemical Ecology, 2007Co-Authors: Stefano Colazza, Ezio Peri, Gloria Aquila, Claudio Pasquale, Jocelyn G. MillarAbstract:Contact Kairomones from adult southern green stink bugs, Nezara viridula (L.) (Heteroptera: Pentatomidae) that elicit foraging behavior of the egg parasitoid Trissolcus basalis (Wollaston) were investigated in laboratory experiments. Chemical residues from tarsi and scutella of N. viridula induced foraging by gravid female T. basalis . Residues from body parts of female N. viridula elicited stronger responses than those from the corresponding body parts of males. Deproteinized tarsi still elicited searching responses from wasps, indicating that the Kairomone was not proteinaceous. Hexane extracts of host cuticular lipids induced searching responses from T. basalis , with a strong preference for extracts from female hosts. Extracts consisted primarily of linear alkanes from n C_19 to n C_34, with quantitative and qualitative differences between the sexes. Extracts of female N. viridula contained more n C_23, n C_24, and n C_25 than the corresponding extracts from males, whereas n C_19 was detected only in extracts from males. Direct-contact solid phase microextraction (DC-SPME) of N. viridula cuticle and of residues left by adult bugs walking on a glass plate confirmed gender-specific differences in n C_19. Trissolcus basalis females responded weakly to a reconstructed blend of the straight-chain hydrocarbons, suggesting that minor components other than linear alkanes must be part of the Kairomone. Addition of n C_19 to hexane extracts of female N. viridula significantly reduced the wasps’ arrestment responses, similar to wasps’ responses to hexane extracts of male hosts. Overall, our results suggest that a contact Kairomone that elicits foraging by T. basalis females is present in the cuticular lipids of N. viridula , and that the presence or absence of n C_19 allows T. basalis females to distinguish between residues left by male or female hosts. The ecological significance of these results in the host location behavior of scelionid egg parasitoids is discussed.
Ezio Peri - One of the best experts on this subject based on the ideXlab platform.
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lures for red palm weevil trapping systems aggregation pheromone and synthetic Kairomone
Pest Management Science, 2017Co-Authors: Sandra Vacas, Stefano Colazza, Ourania Melita, Antonios Michaelakis, Panagiotis G Milonas, R L Minuz, Paola Riolo, Mohamed Kamal Abbass, Paolo Lo Bue, Ezio PeriAbstract:BACKGROUND The optimisation of the lure is essential for the implementation of trapping systems to control insect pests. In this work, the response of the red palm weevil (RPW), Rhynchophorus ferrugineus Olivier, to increasing emission rates of its aggregation pheromone (ferrugineol) and the efficacy of a convenient synthetic Kairomone based on fermentation odours (ethyl acetate and ethanol) have been evaluated in different years and locations along the Mediterranean basin. RESULTS In general, although capture data and emission had noticeable variability among locations, significantly fewer RPW were captured in pyramidal Picusan® traps with the lowest ferrugineol emission rates tested (0.6–3.8 mg day−1). Captures increased rapidly with ferrugineol emission up to 4–5 mg day−1; then, higher emission rates did not improve or reduce captures, up to the highest emission rate tested of 50.9 mg day−1. Thus, there is no evidence of an optimum release rate corresponding to a maximum of RPW catches. Traps baited with the synthetic Kairomone (1:3 ethyl acetate/ethanol) captured 1.4–2.2 times more total weevils than traps baited only with ferrugineol. Moreover, in most of the locations, the synthetic blend was at least as effective as the local coattractants used (plant material + molasses). CONCLUSIONS Ferrugineol emission rate can vary in a wide range without significantly affecting RPW response. Coattractants based on fermenting compounds, ethyl acetate and ethanol, are able to improve the attractant level of ferrugineol and could be employed to replace non-standardised natural Kairomones in RPW trapping systems after further optimisation of their proportions and doses. © 2016 Society of Chemical Industry
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Host Kairomone learning and foraging success in an egg parasitoid: a simulation model
Ecological Entomology, 2009Co-Authors: Guillaume Dauphin, Ezio Peri, Stefano Colazza, Patrick Coquillard, Eric WajnbergAbstract:Trissolcus basalis (Wollaston) (Hymenoptera: Scelionidae) is an egg parasitoid that recognises chemical residues left by its host the green stink bug Nezara viridula (L.) (Heteroptera: Pentatomidae) as Kairomone signals, enabling it to find egg masses in which to lay eggs. 2. Kairomones are usually present as patches deposited by N. viridula females, and recent results (Peri et al. , Journal of Experimental Biology , 209 , 3629 - 3635, 2006) indicated that females of T. basalis are able to learn the features of their foraging environment and to adjust accordingly the amount of time spent on the patches of Kairomones they are visiting, depending on whether or not host eggs are found. 3. In order to assess the impact of this learning ability, a Monte Carlo, spatially explicit and individual-based simulation model was built to quantify the foraging efficiency of T. basalis females in environments with different levels of host abundance and distribution. In all cases, the present study compared the foraging efficiency of simulated T. basalis females having the ability to learn with those lacking this ability. 4. Learning females always visited a higher number of Kairomone patches and attacked a higher number of hosts than non-learning females, especially when there was a high density of Kairomone patches in the environment. 5. Learning ability globally appears to allow the maintenance of efficient foraging success, especially when there is a low probability for the Kairomone patches to contain discoverable hosts. 6. The increase in foraging efficiency for learning females appears to depend on the characteristics of the habitat in which they are foraging. Results thus suggest that significant variation in learning ability is likely to occur in natural wasp populations facing different environments with different host spatial distributions.
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The Egg Parasitoid Trissolcus basalis uses n-nonadecane, a Cuticular Hydrocarbon from its Stink Bug Host Nezara viridula, to Discriminate Between Female and Male Hosts
Journal of Chemical Ecology, 2007Co-Authors: Stefano Colazza, Ezio Peri, Gloria Aquila, Claudio Pasquale, Jocelyn G. MillarAbstract:Contact Kairomones from adult southern green stink bugs, Nezara viridula (L.) (Heteroptera: Pentatomidae) that elicit foraging behavior of the egg parasitoid Trissolcus basalis (Wollaston) were investigated in laboratory experiments. Chemical residues from tarsi and scutella of N. viridula induced foraging by gravid female T. basalis . Residues from body parts of female N. viridula elicited stronger responses than those from the corresponding body parts of males. Deproteinized tarsi still elicited searching responses from wasps, indicating that the Kairomone was not proteinaceous. Hexane extracts of host cuticular lipids induced searching responses from T. basalis , with a strong preference for extracts from female hosts. Extracts consisted primarily of linear alkanes from n C_19 to n C_34, with quantitative and qualitative differences between the sexes. Extracts of female N. viridula contained more n C_23, n C_24, and n C_25 than the corresponding extracts from males, whereas n C_19 was detected only in extracts from males. Direct-contact solid phase microextraction (DC-SPME) of N. viridula cuticle and of residues left by adult bugs walking on a glass plate confirmed gender-specific differences in n C_19. Trissolcus basalis females responded weakly to a reconstructed blend of the straight-chain hydrocarbons, suggesting that minor components other than linear alkanes must be part of the Kairomone. Addition of n C_19 to hexane extracts of female N. viridula significantly reduced the wasps’ arrestment responses, similar to wasps’ responses to hexane extracts of male hosts. Overall, our results suggest that a contact Kairomone that elicits foraging by T. basalis females is present in the cuticular lipids of N. viridula , and that the presence or absence of n C_19 allows T. basalis females to distinguish between residues left by male or female hosts. The ecological significance of these results in the host location behavior of scelionid egg parasitoids is discussed.
Jeanmarie Delpuech - One of the best experts on this subject based on the ideXlab platform.
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increase of the behavioral response to Kairomones by the parasitoid wasp leptopilina heterotoma surviving insecticides
Archives of Environmental Contamination and Toxicology, 2005Co-Authors: Jeanmarie Delpuech, C Bardon, Michel BoulétreauAbstract:Hymenopterous parasitoids are key species involved in the regulation of insect populations. Kairomone perception is an important step leading to host parasitization. The massive use of insecticides induces environmental pollution that can interact with the reproduction of parasitoids. In this work, we have determined the sublethal effects of two insecticides, an organophosphorus (chlorpyrifos) and a pyrethroid (deltamethrin), on the arrestment, by host Kairomones, of female parasitoids surviving an LD 20 for 24 h. The behavior of the parasitoids has been recorded with a video-computerized system. The analysis of the behaviors in control conditions versus exposed to an LD 20 have shown that both insecticides significantly increased the arrestment of parasitoids by Kairomones. This increase was not followed up by a modification of the kinetics of the behavior. In both control and exposed conditions, parasitoids regularly increased their residence time on the Kairomone patch indicating that no saturation to Kairomones had occurred. In a field situation where hosts could be scarce, this increase in arrestment could be advantageous for parasitoids by increasing their host finding.
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modification by the insecticide chlorpyrifos of the behavioral response to Kairomones of a parasitoid wasp leptopilina boulardi
Archives of Environmental Contamination and Toxicology, 2001Co-Authors: N Komeza, Pierre Fouillet, Michel Boulétreau, Jeanmarie DelpuechAbstract:Parasitoids are key species involved in the regulation of natural populations. Host parasitization is realized via some important steps in which Kairomone perception is essential. Due to the wide use of insecticides and their contribution to environmental pollution, the determination of their sublethal effects on behaviors involved in the reproduction of parasitoids becomes a necessity. In this work, we analyzed the effects of a lethal dose 20% of chlorpyrifos, an organophosphorus insecticide, on the behavior of L. boulardi toward the Kairomone of its host. The insecticide significantly modified the kinetics of the residence time of parasitoids on a patch marked by Kairomones. Females exposed to the insecticide were less efficient in finding the Kairomone patch than control females, and they tended to stay on that patch, whereas control females rapidly left it. These effects are discussed considering the mode of action of the insecticide. Because search time allocation of host is an important component for parasitism efficiency, this modification of behavior could interfere with the reproduction capacity of parasitoids. Therefore, in a context of environmental pollution, the repercussions of such sublethal effects on the population biology of insects need to be considered.
A Weber - One of the best experts on this subject based on the ideXlab platform.
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more than one fish Kairomone perch and stickleback Kairomones affect daphnia life history traits differently
Hydrobiologia, 2003Co-Authors: A WeberAbstract:Life history traits of Daphnia galeata clones were affected differently by Kairomones exuded by two species of fish. The exposure to Gasterosteus Kairomone resulted in an increase in population intrinsic rate of increase and body growth rate relative to the exposure to Perca Kairomone. These differences between fish treatments have not been reported earlier. The results suggest differences between fish Kairomones that are not due to concentration effects alone. This raises the possibility that Kairomones are cocktails of chemicals rather than a single `fish substance'. It also supports the view the effects of size-selective predation vary depending on the local predator–prey assemblage examined. This finding leads to an additional, previously underestimated but potentially complex aspect in zooplankton ecology.
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More than one `fish Kairomone'? Perch and stickleback Kairomones affect Daphnia life history traits differently
Hydrobiologia, 2003Co-Authors: A WeberAbstract:Life history traits of Daphnia galeata clones were affected differently by Kairomones exuded by two species of fish. The exposure to Gasterosteus Kairomone resulted in an increase in population intrinsic rate of increase and body growth rate relative to the exposure to Perca Kairomone. These differences between fish treatments have not been reported earlier. The results suggest differences between fish Kairomones that are not due to concentration effects alone. This raises the possibility that Kairomones are cocktails of chemicals rather than a single `fish substance'. It also supports the view the effects of size-selective predation vary depending on the local predator–prey assemblage examined. This finding leads to an additional, previously underestimated but potentially complex aspect in zooplankton ecology.
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The supposed lack of trade-off among Daphnia galeata life history traits is explained by increased adult mortality in Chaoborus conditioned treatments
Hydrobiologia, 2003Co-Authors: A Weber, S. Vesela, Sari RepkaAbstract:In recent years, some studies addressing the modification of phenotypically plastic traits of Daphnia in the presence of chemical cues (Kairomones) from invertebrate predators have reported a lack of trade-off among resource allocation of traditional life history traits (growth and reproduction) (Spitze, 1991; Black, 1993; Weber & Declerck, 1997). In this study, we term this finding the `Chaoborus paradox'. The Chaoborus paradox contrasts with the generally accepted theory that facultative changes in life history traits are associated with costs or a modification in resource allocation. In order to unravel the Chaoborus paradox, we have tested four groups of traits that may explain resource allocation. These were (1) the trade-off between present and future reproduction, (2) reduced growth of morphological features (body length, helmet length, spine length, carapace width) prior to maturity (pre-maturity) or (3) during the first adult instar (at maturity), and (4) an increase in feeding and assimilation rates to fuel the amount of resources available to the organism. As experimental animal we used Daphnia galeata (Cladocera) and to simulate invertebrate predation we used the Chaoborus (phantom midge larvae) Kairomone. A clear trade-off existed between present and future reproduction. Survival was less in the presence of Chaoborus Kairomone and therefore more resources could be channelled into growth and reproduction early in life at the cost of dying younger when compared to control animals. The other groups of traits (reduced growth of morphological features and an increase the amount of resources) offer partial solutions to the Chaoborus paradox for single clones only and not for the whole population.
Michel Boulétreau - One of the best experts on this subject based on the ideXlab platform.
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increase of the behavioral response to Kairomones by the parasitoid wasp leptopilina heterotoma surviving insecticides
Archives of Environmental Contamination and Toxicology, 2005Co-Authors: Jeanmarie Delpuech, C Bardon, Michel BoulétreauAbstract:Hymenopterous parasitoids are key species involved in the regulation of insect populations. Kairomone perception is an important step leading to host parasitization. The massive use of insecticides induces environmental pollution that can interact with the reproduction of parasitoids. In this work, we have determined the sublethal effects of two insecticides, an organophosphorus (chlorpyrifos) and a pyrethroid (deltamethrin), on the arrestment, by host Kairomones, of female parasitoids surviving an LD 20 for 24 h. The behavior of the parasitoids has been recorded with a video-computerized system. The analysis of the behaviors in control conditions versus exposed to an LD 20 have shown that both insecticides significantly increased the arrestment of parasitoids by Kairomones. This increase was not followed up by a modification of the kinetics of the behavior. In both control and exposed conditions, parasitoids regularly increased their residence time on the Kairomone patch indicating that no saturation to Kairomones had occurred. In a field situation where hosts could be scarce, this increase in arrestment could be advantageous for parasitoids by increasing their host finding.
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modification by the insecticide chlorpyrifos of the behavioral response to Kairomones of a parasitoid wasp leptopilina boulardi
Archives of Environmental Contamination and Toxicology, 2001Co-Authors: N Komeza, Pierre Fouillet, Michel Boulétreau, Jeanmarie DelpuechAbstract:Parasitoids are key species involved in the regulation of natural populations. Host parasitization is realized via some important steps in which Kairomone perception is essential. Due to the wide use of insecticides and their contribution to environmental pollution, the determination of their sublethal effects on behaviors involved in the reproduction of parasitoids becomes a necessity. In this work, we analyzed the effects of a lethal dose 20% of chlorpyrifos, an organophosphorus insecticide, on the behavior of L. boulardi toward the Kairomone of its host. The insecticide significantly modified the kinetics of the residence time of parasitoids on a patch marked by Kairomones. Females exposed to the insecticide were less efficient in finding the Kairomone patch than control females, and they tended to stay on that patch, whereas control females rapidly left it. These effects are discussed considering the mode of action of the insecticide. Because search time allocation of host is an important component for parasitism efficiency, this modification of behavior could interfere with the reproduction capacity of parasitoids. Therefore, in a context of environmental pollution, the repercussions of such sublethal effects on the population biology of insects need to be considered.
