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Christer Lofstedt - One of the best experts on this subject based on the ideXlab platform.
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foraging and mate finding in the silver y moth Autographa Gamma lepidoptera noctuidae under the risk of predation
Oikos, 2003Co-Authors: Niels Skals, Dainius Plepys, Christer LofstedtAbstract:Animal foraging and reproductive behaviour is influenced by other simultaneous demands such as predator avoidance. The trade-offs between these demands may depend on sex or mating experience. This study demonstrates that the olfactory-mediated foraging and mate-seeking behaviours in the silver Y moths, Autographa Gamma, are affected by auditory cues mimicking their bat predators. Both males and females changed their foraging behaviour under simulated predation risk. Fewer moths reached the odour source following sound stimulation and the time to find the odour source increased by up to 250%. However, there were no significant differences between male and female ability to reach the plant odour source or the duration of the flight towards the source when stimulated with ultrasound. Hence females are not more cautious than males when observed in the same behavioural context. Risk-taking in males was independent of whether they were flying toward a flower odour or sex pheromones having equal attractive value. This indicates that the trade-off between olfactory and acoustic cues is independent the type of odour. Mated females were not as strongly affected by sound as non-mated, indicating that flower odours have a higher adaptive value for mated females, suggesting that some processes following mating experience influence the trade-off between flower odours and simulated bat sounds.
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volatiles from flowers of platanthera bifolia orchidaceae attractive to the silver y moth Autographa Gamma lepidoptera noctuidae
Oikos, 2002Co-Authors: Dainius Plepys, Fernando Ibarra, Christer LofstedtAbstract:We examined the attractiveness of a natural headspace sample of Platanthera bifolia blossoms, synthetic blends and single compounds to the silver Y moth, Autographa Gamma, in a flight tunnel. The synthetic blend consisted of previously identified electrophysiologically active compounds from P. bifolia: benzyl benzoate, benzyl salicylate, cinnamyl alcohol, lilac aldehydes, methyl benzoate and methyl salicylate. This blend had a similar attractivity as the natural headspace sample. Subtraction of lilac aldehydes significantly decreased attractiveness of the synthetic blend. When a mixture of lilac aldehydes was tested alone, it showed attractiveness similar to that of the synthetic blend. One or a mixture of lilac aldehydes accounts for the attraction of moths to P. bifolia. All other compounds elicited significantly lower responses. Results are discussed in relation to the pollination biology of P. bifolia.
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odour mediated nectar foraging in the silver y moth Autographa Gamma lepidoptera noctuidae behavioural and electrophysiological responses to floral volatiles
Oikos, 2002Co-Authors: Dainius Plepys, Fernando Ibarra, Wittko Francke, Christer LofstedtAbstract:Naive male and female silver Y moths, Autographa Gamma (Lepidoptera: Noctuidae), were attracted in a flight tunnel assay to potted creeping thistle, Cirsium arvense (Asteraceae), butterfly-orchid, Platanthera bifolia (Orchidaceae), soapwort, Saponaria officinalis (Caryophyllaceae), greater knapweed, Centaurea scabiosa (Asteraceae), red clover, Trifolium pratense (Fabaceae), and catnip, Nepeta faasseni (Labiatae), plants with flowers. The most attractive plants were C. arvense, P. bifolia and S. officinalis that elicited 87, 78 and 65% source contacts, respectively. C. scabiosa was less attractive eliciting 43% response. T. pratense and N. faasseni showed the least attraction eliciting 28 and 26% source contacts, respectively. A cotton plant used as control, was not attractive. Floral volatiles from the investigated plant species were collected using headspace sampling technique. Samples were analysed using gas chromatography coupled with electroantennographic detection, and electrophysiologically active compounds were identified by coupled gas chromatography/mass spectrometry. Consistent electrophysiological responses were elicited by twelve compounds from headspace of C. arvense, thirteen compounds from P. bifolia, eleven compounds from S. officinalis, nine from C. scabiosa, ten from T. pratense and two from N. faasseni. Most of the active compounds were specific for one or two species, while benzyl benzoate was present in four and benzaldehyde and benzyl alcohol in three species. Floral scents of C. arvense, P. bifolia and S. officinalis, the most attractive flowers, were dominated by aromatic compounds that were not abundant in the scent of other flowers. To conclude, the results demonstrate the absence of a common denominator of odours present in flowers of different plants visited by A. Gamma.
A. G. Gatehouse - One of the best experts on this subject based on the ideXlab platform.
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effects of temperature and photoperiod on development and pre reproductive period of the silver y moth Autographa Gamma lepidoptera noctuidae
Bulletin of Entomological Research, 1992Co-Authors: Jane K. Hill, A. G. GatehouseAbstract:Adults of Autographa Gamma (Linnaeus) make regular, seasonal migrations into areas where they are unable to breed continuously. Individuals migrate into Britain each spring, and after one, two or three generations, offspring of the spring migrants return to over-wintering areas in North Africa and the Middle East. The larvae are highly polyphagous and have been recorded damaging many crops, especially Brassica spp. Insects usually migrate during the adults' pre-reproductive period (PRP). The length of this period is therefore an index of migratory potential since individuals with longer PRPs have more time to express their capacity for flight and to travel further. Individuals reared outside in Britain in autumn have longer PRPs than individuals reared outside in summer. Laboratory experiments show that PRPs are extended at low temperatures and under short photoperiods and there is some evidence that PRPs are also extended under gradually decreasing photoperiods. By extending PRPs in response to environmental conditions typical of Britain in autumn, individuals are able to increase their potential for pre-reproductive migratory flight and therefore their potential for reaching suitable overwintering sites further south.
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Genetic control of the pre-reproductive period in Autographa Gamma (L.) (Silver Y moth) (Lepidoptera: Noctuidae)
Heredity, 1992Co-Authors: Jane K. Hill, A. G. GatehouseAbstract:Genetic control of the pre-reproductive period in Autographa Gamma (L.) (Silver Y moth) (Lepidoptera: Noctuidae)
Dainius Plepys - One of the best experts on this subject based on the ideXlab platform.
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foraging and mate finding in the silver y moth Autographa Gamma lepidoptera noctuidae under the risk of predation
Oikos, 2003Co-Authors: Niels Skals, Dainius Plepys, Christer LofstedtAbstract:Animal foraging and reproductive behaviour is influenced by other simultaneous demands such as predator avoidance. The trade-offs between these demands may depend on sex or mating experience. This study demonstrates that the olfactory-mediated foraging and mate-seeking behaviours in the silver Y moths, Autographa Gamma, are affected by auditory cues mimicking their bat predators. Both males and females changed their foraging behaviour under simulated predation risk. Fewer moths reached the odour source following sound stimulation and the time to find the odour source increased by up to 250%. However, there were no significant differences between male and female ability to reach the plant odour source or the duration of the flight towards the source when stimulated with ultrasound. Hence females are not more cautious than males when observed in the same behavioural context. Risk-taking in males was independent of whether they were flying toward a flower odour or sex pheromones having equal attractive value. This indicates that the trade-off between olfactory and acoustic cues is independent the type of odour. Mated females were not as strongly affected by sound as non-mated, indicating that flower odours have a higher adaptive value for mated females, suggesting that some processes following mating experience influence the trade-off between flower odours and simulated bat sounds.
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volatiles from flowers of platanthera bifolia orchidaceae attractive to the silver y moth Autographa Gamma lepidoptera noctuidae
Oikos, 2002Co-Authors: Dainius Plepys, Fernando Ibarra, Christer LofstedtAbstract:We examined the attractiveness of a natural headspace sample of Platanthera bifolia blossoms, synthetic blends and single compounds to the silver Y moth, Autographa Gamma, in a flight tunnel. The synthetic blend consisted of previously identified electrophysiologically active compounds from P. bifolia: benzyl benzoate, benzyl salicylate, cinnamyl alcohol, lilac aldehydes, methyl benzoate and methyl salicylate. This blend had a similar attractivity as the natural headspace sample. Subtraction of lilac aldehydes significantly decreased attractiveness of the synthetic blend. When a mixture of lilac aldehydes was tested alone, it showed attractiveness similar to that of the synthetic blend. One or a mixture of lilac aldehydes accounts for the attraction of moths to P. bifolia. All other compounds elicited significantly lower responses. Results are discussed in relation to the pollination biology of P. bifolia.
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odour mediated nectar foraging in the silver y moth Autographa Gamma lepidoptera noctuidae behavioural and electrophysiological responses to floral volatiles
Oikos, 2002Co-Authors: Dainius Plepys, Fernando Ibarra, Wittko Francke, Christer LofstedtAbstract:Naive male and female silver Y moths, Autographa Gamma (Lepidoptera: Noctuidae), were attracted in a flight tunnel assay to potted creeping thistle, Cirsium arvense (Asteraceae), butterfly-orchid, Platanthera bifolia (Orchidaceae), soapwort, Saponaria officinalis (Caryophyllaceae), greater knapweed, Centaurea scabiosa (Asteraceae), red clover, Trifolium pratense (Fabaceae), and catnip, Nepeta faasseni (Labiatae), plants with flowers. The most attractive plants were C. arvense, P. bifolia and S. officinalis that elicited 87, 78 and 65% source contacts, respectively. C. scabiosa was less attractive eliciting 43% response. T. pratense and N. faasseni showed the least attraction eliciting 28 and 26% source contacts, respectively. A cotton plant used as control, was not attractive. Floral volatiles from the investigated plant species were collected using headspace sampling technique. Samples were analysed using gas chromatography coupled with electroantennographic detection, and electrophysiologically active compounds were identified by coupled gas chromatography/mass spectrometry. Consistent electrophysiological responses were elicited by twelve compounds from headspace of C. arvense, thirteen compounds from P. bifolia, eleven compounds from S. officinalis, nine from C. scabiosa, ten from T. pratense and two from N. faasseni. Most of the active compounds were specific for one or two species, while benzyl benzoate was present in four and benzaldehyde and benzyl alcohol in three species. Floral scents of C. arvense, P. bifolia and S. officinalis, the most attractive flowers, were dominated by aromatic compounds that were not abundant in the scent of other flowers. To conclude, the results demonstrate the absence of a common denominator of odours present in flowers of different plants visited by A. Gamma.
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odour mediated nectar foraging in the silver y moth Autographa Gamma
2001Co-Authors: Dainius PlepysAbstract:It is well established that floral odours play a significant role in the nectar foraging behaviour in Lepidoptera and other insect orders. Floral odour may elicit searching, alighting and feeding behaviours alone or in concert with visual stimuli. The goal of the present project was to investigate attractiveness of different species of flowers to the silver Y moth, to identify constituents of volatile floral components responsible for this attraction, and to study how they are processed in the peripheral nervous system. Moth's foraging as well as mate-finding behaviour is altered by the risk of bat predation. Thus I also studied if males and females take different risks when preyed upon, and if male risk taking depends on the nature of stimuli. Attractivity of six flower species differed in the flight tunnel assay. This difference can be explained by a difference in the emission rate of volatiles, by difference in innate preferences for specific compounds or by a combination of both factors. Gas chromatographic–electroantennographic analysis demonstrated the absence of a common volatile compound present in flowers of different plants visited by A. Gamma. Forty-four electrophysiologically active compounds were identified. Employing the single sensillum recording method I found that these compounds are detected with high selectivity and sensitivity by the olfactory receptor neurones (ORNs) of the moth. Eleven ORN types were identified. ORNs responding to lilac aldehydes, cinnamyl alcohol, a-farnesene and cis-trans-nepetalactone were the most abundant. A flight tunnel assay revealed that lilac aldehyde(s) are the major attractive compound(s) responsible for the attraction of moths to the flowers of an orchid Platanthera bifolia. To test attractivity of extracts, blends and individual compounds an ultrasonic sprayer was used for release of stimuli. Noctuid moths are able to hear the ultrasound emitted by the sprayer that affects their behaviour. The sprayer was improved to eliminate the negative sound effect by introducing a new piezo ceramic transducer able to generate 300 kHz frequency sound that is beyond the hearing threshold of the moth. Males did not take a higher risk under the simulated bat predation than females; neither male risk taking was dependent on whether they were stimulated by floral odour or a pheromone.
Jane K. Hill - One of the best experts on this subject based on the ideXlab platform.
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seasonal migration to high latitudes results in major reproductive benefits in an insect
Proceedings of the National Academy of Sciences of the United States of America, 2012Co-Authors: Jane K. Hill, Jason W Chapman, D R Reynolds, James R Bell, Laura Burgin, Lars B Pettersson, Michael B Bonsall, J A ThomasAbstract:Little is known of the population dynamics of long-range insect migrants, and it has been suggested that the annual journeys of billions of nonhardy insects to exploit temperate zones during summer represent a sink from which future generations seldom return (the “Pied Piper” effect). We combine data from entomological radars and ground-based light traps to show that annual migrations are highly adaptive in the noctuid moth Autographa Gamma (silver Y), a major agricultural pest. We estimate that 10–240 million immigrants reach the United Kingdom each spring, but that summer breeding results in a fourfold increase in the abundance of the subsequent generation of adults, all of which emigrate southward in the fall. Trajectory simulations show that 80% of emigrants will reach regions suitable for winter breeding in the Mediterranean Basin, for which our population dynamics model predicts a winter carrying capacity only 20% of that of northern Europe during the summer. We conclude not only that poleward insect migrations in spring result in major population increases, but also that the persistence of such species is dependent on summer breeding in high-latitude regions, which requires a fundamental change in our understanding of insect migration.
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phenotypic plasticity and geographical variation in the pre reproductive period of Autographa Gamma lepidoptera noctuidae and its implications for migration in this species
Ecological Entomology, 1993Co-Authors: Jane K. Hill, Gavin A GatehouseAbstract:. 1 Adults of the noctuid moth Autographa Gamma undertake seasonal migrations into areas where they are unable to breed continuously. Individuals migrate into Britain each spring, and offspring of these migrants probably return in autumn to over-wintering areas in North Africa and the Middle East. However, the existence of these return migrations has been questioned. 2 Insects usually migrate during the adults' pre-reproductive period (PRP). The length of this period is therefore an index of migratory potential since individuals with longer PRPs have more time to express their potential for flight and to travel further before becoming sexually mature. 3 Offspring of insects from Morocco, Britain and Germany showed that, under both long and short photoperiods, PRP increased with latitude over the range 34–53°N. There were significant genotype—environment interactions in the effect of photoperiod on length of PRP. 4 However, PRPs of offspring from insects collected in Sweden were no different under a long photoperiod from those of offspring collected further south, and were significantly shorter under a short photoperiod than those of insects from Morocco. 5 With the exception of Swedish moths, offspring from insects collected at higher latitudes had longer PRPs and, therefore, the potential to travel further during migrations. The ability of some individuals to respond to environmental cues signalling habitat deterioration will further increase their potential to return to over-wintering areas further south.
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effects of temperature and photoperiod on development and pre reproductive period of the silver y moth Autographa Gamma lepidoptera noctuidae
Bulletin of Entomological Research, 1992Co-Authors: Jane K. Hill, A. G. GatehouseAbstract:Adults of Autographa Gamma (Linnaeus) make regular, seasonal migrations into areas where they are unable to breed continuously. Individuals migrate into Britain each spring, and after one, two or three generations, offspring of the spring migrants return to over-wintering areas in North Africa and the Middle East. The larvae are highly polyphagous and have been recorded damaging many crops, especially Brassica spp. Insects usually migrate during the adults' pre-reproductive period (PRP). The length of this period is therefore an index of migratory potential since individuals with longer PRPs have more time to express their capacity for flight and to travel further. Individuals reared outside in Britain in autumn have longer PRPs than individuals reared outside in summer. Laboratory experiments show that PRPs are extended at low temperatures and under short photoperiods and there is some evidence that PRPs are also extended under gradually decreasing photoperiods. By extending PRPs in response to environmental conditions typical of Britain in autumn, individuals are able to increase their potential for pre-reproductive migratory flight and therefore their potential for reaching suitable overwintering sites further south.
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Genetic control of the pre-reproductive period in Autographa Gamma (L.) (Silver Y moth) (Lepidoptera: Noctuidae)
Heredity, 1992Co-Authors: Jane K. Hill, A. G. GatehouseAbstract:Genetic control of the pre-reproductive period in Autographa Gamma (L.) (Silver Y moth) (Lepidoptera: Noctuidae)
Fernando Ibarra - One of the best experts on this subject based on the ideXlab platform.
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volatiles from flowers of platanthera bifolia orchidaceae attractive to the silver y moth Autographa Gamma lepidoptera noctuidae
Oikos, 2002Co-Authors: Dainius Plepys, Fernando Ibarra, Christer LofstedtAbstract:We examined the attractiveness of a natural headspace sample of Platanthera bifolia blossoms, synthetic blends and single compounds to the silver Y moth, Autographa Gamma, in a flight tunnel. The synthetic blend consisted of previously identified electrophysiologically active compounds from P. bifolia: benzyl benzoate, benzyl salicylate, cinnamyl alcohol, lilac aldehydes, methyl benzoate and methyl salicylate. This blend had a similar attractivity as the natural headspace sample. Subtraction of lilac aldehydes significantly decreased attractiveness of the synthetic blend. When a mixture of lilac aldehydes was tested alone, it showed attractiveness similar to that of the synthetic blend. One or a mixture of lilac aldehydes accounts for the attraction of moths to P. bifolia. All other compounds elicited significantly lower responses. Results are discussed in relation to the pollination biology of P. bifolia.
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odour mediated nectar foraging in the silver y moth Autographa Gamma lepidoptera noctuidae behavioural and electrophysiological responses to floral volatiles
Oikos, 2002Co-Authors: Dainius Plepys, Fernando Ibarra, Wittko Francke, Christer LofstedtAbstract:Naive male and female silver Y moths, Autographa Gamma (Lepidoptera: Noctuidae), were attracted in a flight tunnel assay to potted creeping thistle, Cirsium arvense (Asteraceae), butterfly-orchid, Platanthera bifolia (Orchidaceae), soapwort, Saponaria officinalis (Caryophyllaceae), greater knapweed, Centaurea scabiosa (Asteraceae), red clover, Trifolium pratense (Fabaceae), and catnip, Nepeta faasseni (Labiatae), plants with flowers. The most attractive plants were C. arvense, P. bifolia and S. officinalis that elicited 87, 78 and 65% source contacts, respectively. C. scabiosa was less attractive eliciting 43% response. T. pratense and N. faasseni showed the least attraction eliciting 28 and 26% source contacts, respectively. A cotton plant used as control, was not attractive. Floral volatiles from the investigated plant species were collected using headspace sampling technique. Samples were analysed using gas chromatography coupled with electroantennographic detection, and electrophysiologically active compounds were identified by coupled gas chromatography/mass spectrometry. Consistent electrophysiological responses were elicited by twelve compounds from headspace of C. arvense, thirteen compounds from P. bifolia, eleven compounds from S. officinalis, nine from C. scabiosa, ten from T. pratense and two from N. faasseni. Most of the active compounds were specific for one or two species, while benzyl benzoate was present in four and benzaldehyde and benzyl alcohol in three species. Floral scents of C. arvense, P. bifolia and S. officinalis, the most attractive flowers, were dominated by aromatic compounds that were not abundant in the scent of other flowers. To conclude, the results demonstrate the absence of a common denominator of odours present in flowers of different plants visited by A. Gamma.
