| 1. |
- Hedlund, Katarina, et al.
(författare)
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Utmaningar och möjligheter
- 2022
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Ingår i: Markanvändning för en klimatpositiv framtid : En rapport om utmaningar och möjligheter i Skåne - En rapport om utmaningar och möjligheter i Skåne. - 9789198434996 - 9789198434989 ; , s. 48-60
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 2. |
- Löfstedt, Christer, et al.
(författare)
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Pheromonal secretions from glands on the 5th abdominal sternite of hydropsychid and rhyacophilid caddisflies (Trichoptera)
- 1994
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Ingår i: Journal of Chemical Ecology. - 0098-0331. ; 20:1, s. 153-170
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Tidskriftsartikel (refereegranskat)abstract
- Extracts of different body parts of adult Trichoptera were tested for electrophysiological activity. Extracts of the IVth and Vth abdominal sternites of female Hydropsyche angustipennis, Rhyacophila nubila, and R. fasciata, containing a paired exocrine gland, elicited significant electroan-tennographic responses when tested on conspecific male antennae. The paired gland occurs also in males of all the species, and in H. angustipennis, extracts from males were more active than female extracts when tested on male antennae. Female and male extracts from all species were analyzed by gas chromatography with simultaneous flame ionization and electroantennographic detection (EAD). EAD-active peaks in female extracts, stimulating male antennae, were identified in H. angustipennis as nonan-2-one; and in R. nubila and R. fasciata as heptan-2-one, heptan-2-ol, nonan-2-one, and nonan-2-ol. EAD-active components from male H. angustipennis stimulating male antennae were octan-2-one, nonan-2-one (major peak), (Z)-6-nonen-2-one, decan-2-one, and a methylbranched decan-2-one. Female extracts and synthetic mixtures of compounds identified from female H. angustipennis and R. fasciata were tested for attractivity in the field. High catches with control traps obscured the results, but a synthetic mixture of the four identified compounds was significantly attractive and not different from female extracts for attracting male R. fasciata. In H. angustipennis, a synthetic six-component male blend, in which nonan-2-one was the major component, attracted significant numbers of male and female H. angustipennis. Extracts of male R. nubila and R. fasciata contained acetophenone and hexanoic and octanoic acids but did not have any electrophysiological or behavioral activity on either male or female antennae of conspecifics. The occurrence of a female sex pheromone in Rhyacophila and an aggregation pheromone in Hydropsyche corresponds to earlier described differences in mating behaviors in the Rhyacophilidae and Hydropsychidae.
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| 3. |
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| 4. |
- Svensson, Glenn, et al.
(författare)
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Mating disruption in Agrotis segetum monitored by harmonic radar
- 2001
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Ingår i: Entomologia Experimentalis et Applicata. - : Wiley. - 1570-7458 .- 0013-8703. ; 101:2, s. 111-121
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Tidskriftsartikel (refereegranskat)abstract
- The long-range, pheromone-mediated, flight behaviour of male moths under natural and mating disruption conditions was monitored by means of harmonic radar. Individual male turnip moths, Agrotis segetum (Denis & Schiffermüller) (Lepidoptera: Noctuidae), tagged with radar transponders, were released and tracked in plots with or without disruptive doses of sex pheromone. In addition, male attraction to pheromone-baited traps and mating of calling females in treated and untreated plots was investigated. High doses of a four-component pheromone blend reduced trap catch by 79% and mating of females by 62% when compared with control plots in pre-radar experiments. Surprisingly, this effect was not associated with any pronounced differences in flight behaviour of males between a treatment and a control plot as revealed by harmonic radar recordings. In total, 20 flight tracks from a control plot and 22 flight tracks from a treatment plot were analysed. Moths could be followed for up to 77 min, corresponding to a track length of 7350 m. Mean ground speed ranged from 0.7 m s1 to 5.4 m s1. There was a strong trend (P = 0.06) for a greater number of male orientations to traps from downwind in the control field compared to the treatment field. Many flight tracks were fragmented due to radar shadow. Advantages and constraints using harmonic radar to study the pheromone-mediated flight behaviour of nocturnal moths are discussed.
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| 5. |
- Valeur, Peter G., et al.
(författare)
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Real-time measurement of pheromone release from individual female moths and synthetic dispensers in a wind tunnel by recording of single receptor-neurone responses
- 1999
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Ingår i: Physiological Entomology. - : Wiley. - 0307-6962 .- 1365-3032. ; 24:3, s. 240-250
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Tidskriftsartikel (refereegranskat)abstract
- Measurements of single neurone activity in the peripheral pheromone receptors of male Agrotis segetum (Denis and Schiffermuller) (Lepidoptera: Noctuidae) were performed in a wind tunnel using a portable electrophysiological recording unit. Filter paper and rubber septa loaded with synthetic sex pheromone, as well as individual conspecific female glands, were used as pheromone sources. Recordings, up to 3 h long, were analyzed for temporal variation in spiking activity. The recordings were performed 2 m downwind of the source, where the pheromone plume had a width of approximately 12 cm, as could be measured with the single cell preparations. The system allowed reliable measurements of relative pheromone concentration with a 20-s time resolution. The release rate from rubber septa loaded with pheromone was more or less constant over time, whereas the release rate from filter paper loaded with pheromone decreased to one tenth of the initial value within 6 min from the application of the pheromone. The release of pheromone from female pheromone glands was pulsed with an interval of 2-10 min between bursts. This pulsing was not caused by retraction of the gland, as the glands were forcibly extruded during the entire experiment, but should reflect variation in transport of pheromone to the gland surface and subsequent release. The demonstrated stability of the preparations using tungsten electrodes, the reliable monitoring of female-produced pheromone plumes at several metres distance, and the time resolution obtained are important steps towards field monitoring of natural pheromone plumes, as well as pheromone concentration and distribution in applications for mating disruption.
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| 6. |
- Valeur, Peter
(författare)
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Male moth behaviour and perception in pheromone plumes
- 1998
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Behaviour of male moths and electrophysiological responses of male pheromone-specific olfactory receptor neurones were studied in two model species, the oriental fruit moth Grapholita molesta and the turnip moth Agrotis segetum. The studies were aimed at elucidating the relative importance of different mating disruption mechanisms. In a wind tunnel study of G. molesta, behavioural response to a reference pheromone source was tentatively suppressed by pheromone released from a second treatment source. Manipulations of the treatment composition and concentration, revealed that the adaptation/habituation of the olfactory system had the biggest effect, followed by the false trail following mechanism, and that the complete blend was better than any reduced blend. In a study where A. segetum males were preexposed to a series of blends and concentrations of pheromone, the behavioural performance was significantly more affected than electroantennographic responses. Central nervous habituation is thus the most likely explanation to most of the observed behavioural effects. A comparison with field data in the literature showed that long-term adaptation/habituation is an unlikely explanation to the mating disruption effect observed in practical field applications. In a wind tunnel, a portable single-neurone recording unit was used to analyse pheromone plumes from female glands and different dispensers. Behavioural in-flight arrestment started occurring at concentrations that elicited maximum spiking activity in peripheral receptor neurones. Individual female pheromone release rates were measured in real time, and compared to the release rate from synthetic dispensers. A hitherto unknown degree of short-time variation in female pheromone release rate was revealed. With the help of a novel radar technique, up to 300 m long flight tracks of individual A. segetum males were recorded. Males tended to fly straight crosswind outside of pheromone plumes and up or downwind when in an area with pheromone.
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| 7. |
- Valeur, Peter, et al.
(författare)
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Relationship between sex pheromone elicited behaviour and response of single olfactory receptor neurones in a wind tunnel
- 2000
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Ingår i: Physiological Entomology. - : Wiley. - 0307-6962 .- 1365-3032. ; 25:3, s. 223-232
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Tidskriftsartikel (refereegranskat)abstract
- Responses from pheromone-specific receptor neurones in male Agrotis segetum (Denis & Schiffermuller) (Lepidoptera: Noctuidae) were recorded in a laboratory wind tunnel. Stimuli were: (1) rubber septum dispensers loaded with single components or a four-component pheromone blend, (2) excised glands from female A. segetum, (3) constrained A. segetum females with extruded glands. Dose-response curves for three neurone-types with different specificity were established. The neurones were specifically tuned to respond to either one of the two pheromone components (Z)-5-decenyl acetate and (Z)-7-dodecenyl acetate, or to the behavioural antagonist (Z)-5-decenol. In parallel, a behavioural dose-response curve with males flying upwind to a four-component pheromone blend was established. There was a clear correlation between behavioural arrestment of upwind flight and maximum spiking activity in ZS-10:OAc-specific neurones. The pheromone release rates of individual females and synthetic dispensers were compared. A load of 50-200 ng of ZS-10:OAc on a rubber septum elicited approximately the same neural response as one female gland.
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| 8. |
- Zhu, J. W., et al.
(författare)
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Reidentification of the female sex pheromone of the Indian meal moth, Plodia interpunctella : evidence for a four-component pheromone blend
- 1999
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Ingår i: Entomologia Experimentalis et Applicata. - : Wiley. - 0013-8703 .- 1570-7458. ; 92:2, s. 137-146
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Tidskriftsartikel (refereegranskat)abstract
- Pheromone gland extracts from calling female Plodia interpunctella contained at least seven compounds that consistently elicited electroantennographic responses from male antennae upon gas chromatographic analysis. Three of these compounds were found to be the previously identified gland constituents, i.e., (Z,E)-9,12-tetradecadienyl acetate (Z9,E12-14:OAc), (Z,E)-9,12-tetradecadienal (Z9,E12-14:Ald) and (Z,E)-9,12-tetradecadienol (Z9,E12-14:OH). A fourth EAD-active compound was identified as (Z)-9-tetradecenyl acetate (Z9-14:OAc). The homologue (Z)-11-hexadecenyl acetate (Z11-16:OAc) was also identified in the extracts, but showed no EAD activity. The identity of all five compounds was confirmed by comparison of GC retention times and mass spectra with those of synthetic standards. In flight tunnel tests there were no significant differences in response of male P. interpunctella to the bait containing all four EAD-active compounds and the responses to female gland extacts. A behavioural assay of different two-compound blends in the flight tunnel showed that only addition of the corresponding aldehyde to the major pheromone component Z9,E12-14:OAc raised the male response. A subtractive assay, however, revealed that the exclusion of any of the compounds from the complete four-compound blend reduced its activity significantly. We thus conclude that the female-produced sex pheromone of P. interpunctella consists of at least four components, i.e., Z9,E12-14:OAc, Z9,E12-14:Ald, Z9,E12-14:OH and Z9-14:OAc. In a field trapping test performed in a storage facility, the four-component blend attracted significantly more males of P. interpunctella than traps baited with Z9,E12-14:OAc alone. In contrast, the highest number of Ephestia kuehniella males was found in the traps baited with this major component, suggesting that the secondary pheromone components contribute to the species specificity of the blend.
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