| 1. |
- Ansebo, L., et al.
(författare)
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Antennal and behavioural response of codling moth Cydia pomonella to plant volatiles
- 2004
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Ingår i: Journal of applied entomology. - : Wiley. - 0931-2048 .- 1439-0418. ; 128:7, s. 488-493
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Tidskriftsartikel (refereegranskat)abstract
- Identification of host volatile compounds attractive to codling moth Cydia pomonella, a most important insect of apple, will contribute to the development of safe control techniques. Synthetic apple volatiles in two doses were tested for antennal and behavioural activity in codling moth. Female antennae strongly responded to (Z)3-hexenol, (Z)3-hexenyl benzoate, (Z)3-hexenyl hexanoate, (+/-)-linalool and E,E-alpha-farnesene. Two other compounds eliciting a strong antennal response were the pear ester, ethyl (E,Z)-2,4-decadienoate, and its corresponding aldehyde, E,E-2,4-decadienal, which is a component of the larval defence secretion of the European apple sawfly. Attraction of codling moth to compounds eliciting a strong antennal response was tested in a wind tunnel. Male moths were best attracted to a blend of (E,E)-alpha-farnesene, (E)-beta-farnesene and ethyl (E,Z)-2,4-decadienoate. The aldehyde E,E-2,4-decadienal had an antagonistic effect when added to the above mixture.
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| 2. |
- Bonjour, Olivier, et al.
(författare)
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Rigid biobased polycarbonates with good processability based on a spirocyclic diol derived from citric acid
- 2020
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Ingår i: Green Chemistry. - 1463-9270. ; 22:12, s. 3940-3951
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Tidskriftsartikel (refereegranskat)abstract
- Introducing biobased polymers from renewable sources for use as high-performance thermoplastics with high demands on mechanical rigidity, transparency, thermal stability, as well as good processability, is a significant challenge. In the present work we have designed and prepared a rigid biobased bis-spirocylic diol by di-cycloketalization of a bicyclic diketone (cis-bicyclo[3.3.0]octane-3,7-dione, obtained from citric acid) using trimethylolpropane. This spiro-diol monomer has two reactive primary hydroxyl groups and the synthesis from inexpensive biobased starting materials is straightforward and readily upscalable, involving no chromatographic purification. In order to explore the usefulness of the new monomer, it was employed in melt polycondensations with diphenylcarbonate at up to 280 °C to form rigid fully amorphous polycarbonates (PCs). Molecular weights (MWs) up to Mn = 28 kg mol-1 were achieved, and thermal and dynamic mechanical measurements showed glass transitions up to Tg = 100 °C, with no thermal decomposition until Td ~ 350 °C. Solvent cast films had excellent mechanical flexibility and strength, as well as a high transparency with only slight coloration. Results by dynamic melt rheology implied that the high-MW PCs had a good processability at 170 °C, with a stable shear modulus over time, but started to degrade via chain scission reactions when the temperature approached 200 °C. In conclusion, the present work demonstrates the straightforward preparation of the citric acid-based spiro-diol, and indicates that it is an efficient building block for the preparation of rigid biobased PCs and other condensation polymers.
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| 3. |
- Coracini, M., et al.
(författare)
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Attraction of codling moth males to apple volatiles
- 2004
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Ingår i: Entomologia Experimentalis et Applicata. - : Wiley. - 0013-8703 .- 1570-7458. ; 110:1, s. 1-10
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Tidskriftsartikel (refereegranskat)abstract
- The attraction of the codling moth, Cydia pomonella, to apple volatile compounds known to elicit an antennal response was tested both in the field and in a wind tunnel. In the field, (E)-beta-farnesene captured male moths. The addition of other apple volatiles, including (E,E)-alpha-farnesene, linalool, or (E,E)-farnesol to (E)-beta-farnesene did not significantly augment trap catch. Few females were caught in traps which also caught male moths, but female captures were not significantly different from blank traps. In the wind tunnel, males were attracted to (E,E)-farnesol, but not to (E)-beta-farnesene. The addition of (E,E)-alpha-farnesene to (E)-beta-farnesene had a synergistic effect on male attraction. The male behavioural sequence elicited by plant volatiles, including upwind flight behaviour, was indistinguishable from the behaviour elicited by sex pheromone.
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| 4. |
- El-Sayed, Ashraf, et al.
(författare)
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Flight and molecular modeling study on the response of codling moth, Cydia pomonella (Lepidoptera : Tortricidae) to (E,E)-8,10-dodecadien-1-ol and its geometrical isomers
- 2000
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Ingår i: Zeitschrift für Naturforschung C - A Journal of Biosciences. - : Walter de Gruyter. - 0939-5075 .- 1865-7125. ; 55:11-12, s. 1011-1017
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Tidskriftsartikel (refereegranskat)abstract
- In a previous study we have reported that both (E,Z)-8,10-dodecadienol (E,Z) and (Z,Z) 8,10-dodecadienol (Z,Z) isomers inhibit the attraction of male codling moth, Cydia pomonella L. when added to (E,E)-8,10-dodecadienol (E,E) while the (Z,E)-8,10-dodecadienol (Z,E) isomer induces slight increase in the number of males attracted to the pheromone source. In the present study, we have tested the behavioral activity of the individual geometrical isomers E,Z; Z,E and Z,Z. A few number of codling moth males flew to the Z,E-isomer while the other two isomers (i.e. E,Z and Z,Z) did not elicit any upwind orientation. Analysis of the Right behavior to the E,E- and Z,E-isomer showed significant differences in most of the flight parameters evaluated. Based on the biological observations and molecular modeling, we suggest that the behavioral activity of the Z,E-isomer is due to presence of specific receptors for this isomer on male antennae and not to its structural resemblance to the E,E-isomer. These results underline the importance of the Z,E-isomer in sex attraction of male codling moth.
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| 5. |
- Fors, Lisa, et al.
(författare)
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Chemical communication and host search in Galerucella leaf beetles
- 2015
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Ingår i: Chemoecology. - : Springer Science and Business Media LLC. - 0937-7409 .- 1423-0445. ; 25:1, s. 33-45
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Tidskriftsartikel (refereegranskat)abstract
- Herbivore insects use a variety of search cues during host finding and mate recognition, including visual, gustatory, and olfactory stimuli, leaving multiple traits for evolution to act upon. However, information about differences or similarities in search pattern amongst closely related insect herbivore species is still scarce. Here, we study the production of and the response to pheromone in Galerucella (Coleoptera: Chrysomelidae) to investigate the beetles' search behaviour. Males of G. pusilla and G. calmariensis, two closely related species, are known to produce the aggregation pheromone dimethylfuran-lactone when feeding on their host plant, whereas no pheromones have been identified in other Galerucella species. We show that dimethylfuran-lactone is produced also by males of G. tenella, a species phylogenetically close to G. pusilla and G. calmariensis, whereas the more distantly related species G. lineola and G. sagittariae were not found to produce the same compound. To investigate the beetles' behavioural response to dimethylfuran-lactone, the pheromone was synthesized using a partly novel method and tested in olfactometers, showing that G. pusilla, G. calmariensis, and G. tenella were all attracted to the pheromone, whereas G. lineola and G. sagittariae did not respond. This suggests that the production of and the response to pheromone could be linked to the phylogenetic relatedness between the species.
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| 6. |
- Larsdotter-Mellström, Helena, et al.
(författare)
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It's All in the Mix : Blend-Specific Behavioral Response to a Sexual Pheromone in a Butterfly
- 2016
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Ingår i: Frontiers in Physiology. - : Frontiers Media S.A.. - 1664-042X. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Among insects, sexual pheromones are typically mixtures of two to several components, all of which are generally required to elicit a behavioral response. Here we show for the first time that a complete blend of sexual pheromone components is needed to elicit a response also in a butterfly. Males of the Green-veined White, Pieris napi, emit an aphrodisiac pheromone, citral, from wing glands. This pheromone is requisite for females to accept mating with a courting male. Citral is a mixture of the two geometric isomers geranial (E-isomer) and neral (Z-isomer) in an approximate 1:1 ratio. We found that both these compounds are required to elicit acceptance behavior, which indicates synergistic interaction between processing of the isomers. Using functional Ca2+ imaging we found that geranial and neral evoke significantly different but overlapping glomerular activity patterns in the antennal lobe, which suggests receptors with different affinity for the two isomers. However, these glomeruli were intermingled with glomeruli responding to, for example, plant-related compounds, i.e., no distinct subpopulation of pheromone-responding glomeruli as in moths and other insects. In addition, these glomeruli showed lower specificity than pheromone-activated glomeruli in moths. We could, however, not detect any mixture interactions among four identified glomeruli, indicating that the synergistic effect may be generated at a higher processing level. Furthermore, correlations between glomerular activity patterns evoked by the single isomers and the blend did not change over time.
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| 7. |
- Liblikas, Ilme, et al.
(författare)
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Simplified isolation procedure and interconversion of the diastereomers of nepetalactone and nepetalactol
- 2005
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Ingår i: Journal of natural products (Print). - : American Chemical Society (ACS). - 0163-3864 .- 1520-6025. ; 68:6, s. 886-890
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Tidskriftsartikel (refereegranskat)abstract
- Three nepetalactones were isolated from Nepeta racemosa (mussinii) by traditional methods. An improved method was developed to isolate nepetalactones from N. faassenii. An epimerization procedure was used to prepare the fourth 7S-nepetalactone diastereomer. The cis-fused nepetalactols were prepared by reduction of the corresponding nepetalactones, while the trans-fused nepetalactols were unstable and found to undergo ring-opening reactions yielding iridodials. The characterizations and structural assignments by means of NMR agree with quantum chemical density functional calculations.
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| 8. |
- Liblikas, Ilme, 1959-
(författare)
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Syntheses and behaviour activity of conjugated polyenic pheromone components
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis deals with the synthesis of conjugated dienicand trienic pheromone components- C12-C16alcohols, acetates and aldehydes and theirapplications in pheromone communication studies.Insect pheromones are widely used in modern pest management.The development of effective tools for plant protection is aresult of complex broad, interdisciplinary basic and appliedresearch. A practical use of pheromones for pest managementusually requires that specific active chemicals must beisolated,identified and produced synthetically. The creationof pheromone materials besides requires the identification ofthe active components, determination of the roles of otherpossible isomers or degradation products, the design ofdispensers of suitable substrates and evaporationparameters.The aim of the thesiswas critically to survey methods for the syntheses ofconjugated polyenic compounds and to focus to the synthesis ofseveral conjugated polyenic pheromone components providingsufficient quantities of chemically and isomerically purecompounds for bioassaying.The principal objective of the thesiswas concerned withthe further aim of developing effective synthetic materials forplant protection. The work was focussed:=>To identify the compoundscollected from the leafminer mothPhyllonorycter emberizaepenella(Lepidoptera:Gracillaridae) and perform a detailed identification of thepheromones of the Brazilian apple leafrollerBonagota cranaodes(Meyrick) (Lepidoptera: Tortricidae)and of the codling mothCydia pomonella(L.) (Lepidoptera: Tortricidae). =>Tostudy the effect of non-pheromonal isomers of the mainpheromone component on the sex attraction of B. cranaodes andC.pomonellain wind tunnel and field tests.=>To study the role of identified pheromonecomponents in the pheromone communication of the currant shootborer Lampronia capitella (Cl.) (Lepidoptera: Prodoxidae), andto design and optimize the dispenser for effective trapping.=>To investigate the presence of sex pheromonecomponents in the tobacco hawk mothManduca sexta(L.) (Lepidoptera: Sphingidae).The syntheses of four geometrical isomers of3,5-dodecadienyl acetate; (10E,12E,14Z)- and(10E,12E,14E)-(10,12,14)-hexadecatrien-1-als;(E,Z)-, (Z,E)-,and (Z,Z)-8,10-dodecadienol, codlemone acetate and aldehyde;(9Z,11Z)-9,11-tetradecadienol, corresponding acetate andaldehyde; all geometrical isomers of 8,10-and10,12-tetradecadienols and corresponding acetates wereperformed to ensure all these bioassays with syntheticpheromone components. All compounds were made in high chemicaland stereochemical purity, most of them more than 99%isomerically pure or by using several separation andpurification techniques.The suitable synthetic schemes for the synthesis of all fourgeometrical isomers of four conjugated dienic pheromonecomponents are presented in this thesis.The reactions and purification methods used here exemplifythe wide range of possibilities realized for such syntheses:they present the successful application of many syntheticmethods. The importance of this synthetic work is that thecompounds synthesized are not commercially available or on theother hand the purity of the purchasable compounds is notsatisfactory for research in the field of chemical ecology.Key words:Lepidoptera, sex pheromone, pheromonedispenser, 3,5-dodecadienyl acetate, 10,12,14-hexadecatrienal,8,10-dodecadienol, codlemone atsetate, codlemone aldehyde,8,10- tetradecadienol, 8,10-tetradecadienyl acetate,10,12-tetradecadienol, 10,12-tetradecadienyl acetate,Lampronia capitella, Manduca sexta, Bonagota cranaodes,Cydia pomonella, Phyllonorycter emberizaepenella,conjugated polyenic pheromone, conjugated diene, MPLC,(9Z,11Z)-9,11-tetradecadien-1-ol,(9Z,11Z)-9,11-tetradecadien-1-al
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| 9. |
- Matt, Livia, et al.
(författare)
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Enzymatic synthesis and polymerization of isosorbide-based monomethacrylates for high-Tg plastics
- 2018
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Ingår i: ACS Sustainable Chemistry & Engineering. - : American Chemical Society (ACS). - 2168-0485. ; 6:12, s. 17382-17390
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Tidskriftsartikel (refereegranskat)abstract
- Isosorbide is a stiff bicyclic diol derived from glycose-based polysaccharides, and is thus an attractive building block for novel rigid bioplastics. In the present work a highly regioselective biocatalytic approach for the synthesis of isosorbide 5-methacrylate was developed. The Lipozyme RM IM (Rhizomucor miehei lipase) catalyzed process is straightforward, easily scalable and chromatography-free; a simple extractive workup afforded the monomer at >99% purity and in 87% yield. The developed strategy was applied for the synthesis of a series of monomethacrylated isosorbide derivatives. Radical polymerization of the monomers produced rigid polymethacrylates with a certain side group in either endo or exo configuration, exclusively, which generated materials with great diversity of properties. For example, the two regioisomeric polymers carrying hydroxyl groups reached a glass transition temperature at Tg = 167 °C. The polymer tethered with dodecanoate chains in exo position showed crystallinity with an unexpectedly high melting point at Tm = 83 °C. In contrast, the corresponding sample with dodecanoate chains in endo positions was fully amorphous with Tg = 54 °C. Efficient biocatalytic synthesis combined with attractive polymer properties opens up possibilities for production of these bio-based polymers on an industrial scale.
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| 10. |
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| 11. |
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| 12. |
- Matt, Livia, et al.
(författare)
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Synthesis and anionic polymerization of isosorbide mono-epoxides for linear biobased polyethers
- 2021
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Ingår i: Polymer Chemistry. - 1759-9954. ; 12:41, s. 5937-5941
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Tidskriftsartikel (refereegranskat)abstract
- A series of regioisomeric isosorbide mono-epoxides, as well as diastereomerically pure mono-epoxy derivatives, have been prepared and studied. Anionic ring-opening polymerization of methoxy-capped monomers produced linear polyethers tethered with isosorbide units. These reasonably high molecular weight polymers exhibited glass transition temperatures at around 10-15 °C and thermal stability up to approximately 300 °C, which indicated that the mono-epoxides are promising building blocks for well-defined biobased polymers.
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| 13. |
- Mozuraitis, Raimondas, et al.
(författare)
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Sex pheromone communication of tentiform leaf-miners Phyllonorycter insignitella and Ph. nigrescentella from two related species groups
- 2008
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Ingår i: Chemoecology. - : Springer Science and Business Media LLC. - 0937-7409 .- 1423-0445. ; 18:3, s. 171-176
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Tidskriftsartikel (refereegranskat)abstract
- Females of both species start their pheromone-releasing activity on the second day after emergence at the beginning of the photophase. During the present work, a peak of calling activity with close to 100% of active Ph. nigrescentella females was registered 1.5 hour after the light had been put on. The high pheromone release behaviour with 50% active females lasted for 3 hours. The calling activity of the group of females was about 6 h/day. The beginning of a photophase under laboratory conditions or an early morning in nature is a common period for sex pheromone release in the genus Phyllonorycter. (8Z,10E)-tetradecadien-1-yl acetate (8Z,10E-14:Ac), (8Z,10E)-tetradecadien-1-ol (8Z,10E-14:OH) and (8E,10Z)-tetradecadien-1-yl acetate (8E,10Z-14:Ac) in the ratio 96:4:traces as well as 8Z,10E-14:Ac and 8Z,10E-14:OH in the ratio 88:12 collected by Solid Phase Micro Extraction (SPME) were found to be specific for the calling periods of virgin Phyllonorycter insignitella and Ph. nigrescentella females respectively. Field trapping experiments demonstrated that all three compounds are important for the attraction of Ph. insignitella males while only 8Z,10E-14:Ac is the essential sex pheromone component for Ph. nigrescentella. The pheromone activity of all three compounds is reported for the first time. Addition of either 8Z,10E-14:OH or 8E,10Z-14:Ac to 8Z,10E-14:Ac did not have a significant effect on the attraction of Ph. nigrescentella males, while the efficiency of the three component blend was 5 times lower as compared to that of 8Z,10E-14:Ac. Our data demonstrate that 8Z,10E-14:OH and 8E,10Z-14:Ac play a dual function, they are minor sex pheromone components of Ph. insignitella essential for attraction of conspecific males and show an allelochemical, antagonistic effect on Ph. nigrescentella males and, thus, ensuring specificity of the mate location signal in two related Phyllonorycter species.
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| 14. |
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| 15. |
- Santangelo, Ellen M., et al.
(författare)
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Asymmetric Synthesis of Iridoid Derivatives Using Resolved 2-Phenylindoline as a Chiral Auxiliary
- 2008
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Ingår i: European Journal of Organic Chemistry. - : Wiley. - 1434-193X .- 1099-0690. ; :35, s. 5915-5921
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Tidskriftsartikel (refereegranskat)abstract
- An asymmetric synthetic route to cis,cis-nepetalactol (component of the sex pheromone for the hop aphid, Phorodon humuli) is presented. 2-Phenylindoline was resolved to provide a chiral auxiliary for the cycloaddition of oxocitral. The resolution was made by chromatographic separation of the diastereomers of the urea derivative made from 2-phenylindoline and with (R)-(+)-alpha-methylbenzyl isocyanate, followed by reductive cleavage of the isolated diasteromers using diborane. The cycloaddition of oxocitral using (S)-2-phenylindoline yielded an enantiopure product after chromatography. Hydrolysis of the cycloaddition adduct yielded gastrolactol (3). As gastrolactol is a versatile synthon for the synthesis of iridoids, the overall procedure provides a general asymmetric route to elaborated iridoids.
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| 16. |
- Sedrik, Rauno, et al.
(författare)
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Chemically Recyclable Poly(β-thioether ester)s Based on Rigid Spirocyclic Ketal Diols Derived from Citric Acid
- 2022
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Ingår i: Biomacromolecules. - : American Chemical Society (ACS). - 1526-4602 .- 1525-7797. ; 23:6, s. 2685-2696
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Tidskriftsartikel (refereegranskat)abstract
- Incorporating rigid cyclic acetal and ketal units into polymer structures is an important strategy towards high-performance materials from renewable resources. In the present work, citric acid, a widely used platform chemical derived from biomass, has been efficiently converted into diand tricyclic diketones. Ketalization with glycerol or trimethylolpropane afforded rigid spirodiols, which were obtained as complex mixtures of isomers. After a comprehensive NMR analysis, the spirodiols were converted into the respective di(meth)acrylates and utilized in thiol-ene polymerizations in combination with different dithiols. The resulting poly(β-thioether ester ketal)s were thermally stable up to 300 °C and showed glass transition temperatures in a range from -7 to 40 °C, depending on monomer composition. The polymers were stable in aqueous acids and bases, but in a mixture of 1 M aq. HCl and acetone, the ketal functional groups were cleanly hydrolyzed, opening the pathway for potential chemical recycling of these materials. We envision that these novel bioderived spirodiols have a great potential to become valuable and versatile bio-based building blocks for several different kinds of polymer materials.
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| 17. |
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| 18. |
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| 19. |
- Svensson, Glenn P., et al.
(författare)
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Challenges of pheromone-based mating disruption of Cydia strobilella and Dioryctria abietella in spruce seed orchards
- 2018
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Ingår i: Journal of Pest Science. - : Springer Science and Business Media LLC. - 1612-4758 .- 1612-4766. ; 91, s. 639-650
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Tidskriftsartikel (refereegranskat)abstract
- Seed orchards function as the primary source of high-quality seeds for reforestation in many European countries, but their seed yields can be severely reduced due to seed- and cone-feeding insects. We evaluated various parameters of pheromone-based mating disruption for control of the moths Cydia strobilella and Dioryctria abietella, which are major pests in European Picea abies seed orchards. We applied different types of pheromone dispensers (rubber septa or wax droplets) at different densities and heights, and with different amounts of active components, covering whole orchards or part of an orchard. The efficacy of the treatment was evaluated by analysing male captures in pheromone-baited assessment traps, and presence of larvae in cones. A dramatic decrease (94–100%) in capture of males in traps occurred in all pheromone-treated plots compared to control plots for both moth species. In contrast, a subsequent reduction in larval numbers in cones was only achieved when wax droplets were used as the dispensing formulation at high density and at the highest pheromone dose tested, and only in half of the trials for each pest species. Electrophysiological recordings using antennae of male C. strobilella indicated elevated pheromone concentrations in a treated plot versus a control plot. Our results show that mating disruption has potential to reduce cone damage in spruce seed orchards caused by C. strobilella and D. abietella, but optimisation of the technique is required to achieve consistent and efficient population suppression of these pests.
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| 20. |
- Valterova, Irena, et al.
(författare)
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Male bumble bee pheromonal components in the scent of deceit pollinated orchids; unrecognized pollinator cues?
- 2007
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Ingår i: Arthropod-Plant Interactions. - : Springer Science and Business Media LLC. - 1872-8855 .- 1872-8847. ; 1:3, s. 137-145
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Tidskriftsartikel (refereegranskat)abstract
- The pollination of the non-rewarding Orchis pauciflora was studied. The most abundant visitors of O. pauciflora were B. terrestris queens. The fragrance of O. pauciflora inflorescence was dominated by a sesquiterpene (E)-beta-farnesene. (E,E)-alpha-Farnesene, (E)-2,3-dihydrofarnesol, geranylcitronellol, and the monoterpenes limonene and 1,8-cineol were found among less abundant constituents. The sesqui- and diterpenes detected in O. pauciflora fragrance are frequent constituents of male marking pheromones of many bumble bee species. Enantioselective analysis of O. pauciflora scent and B. terrestris male marking pheromone revealed the presence of the (S)-isomer of (E)-2,3-dihydrofarnesol in both samples, and electrophysiological experiments showed that mainly the (S)-isomer activated the antennal receptors. In field experiments, O. pauciflora inflorescences were enriched with the main compound (E)-beta-farnesene resulting in significantly increased pollinia export. We here discuss the chemical similarities between orchid and bumble bees and whether the presence of bumble bee male pheromone components in O. pauciflora fragrance increases its fitness.
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| 21. |
- Wibe, Atle, et al.
(författare)
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Combining 1,4-dimethoxybenzene, the major flower volatile of wild strawberry Fragaria vesca, with the aggregation pheromone of the strawberry blossom weevil Anthonomus rubi improves attraction
- 2014
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Ingår i: Crop Protection. - : Elsevier BV. - 0261-2194 .- 1873-6904. ; 64, s. 122-128
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Tidskriftsartikel (refereegranskat)abstract
- The aggregation pheromone of strawberry blossom weevil [Anthonomus rubi Herbst (Col.: Curculionidae)1, a 1:4:1 blend of Grandlure I, II and racemic lavadulol, has been available for pest monitoring for several years but shows low attractancy. Attempts to control A. rubi using the pheromone alone were also unsuccessful. This paper reports the finding that addition of the major flower volatile from wild strawberry flowers [Fragaria vesca L. (Rosaceae)], 1,4-dimethoxybenzene (comprising 98% of the volatiles emitted from wild strawberry flowers), to the aggregation pheromone increased trap catches by over two fold compared to the pheromone alone. There was no significant difference between the response of overwintered or summer emerged adults. Field trials in 2007-2008 in central and southern Norway, Denmark and southern England used green funnel traps with white cross vanes for the evaluations. (-)-Germacrene D, previously shown to be emitted by plants in increased amounts in the presence of pheromone producing weevils, did not improve trap catches. Thus, the combined use of the aggregation pheromone and 1,4-dimethoxybenzene is promising for improved monitoring and possibly control of this important pest of strawberry.
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| 22. |
- Witzgall, Peter, et al.
(författare)
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Pheromone communication channels in tortricid moths: lower specificity of alcohol vs. acetate geometric isomer blends
- 2010
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Ingår i: Bulletin of entomological research. - 0007-4853 .- 1475-2670. ; 100:2, s. 225-230
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Tidskriftsartikel (refereegranskat)abstract
- Discrimination of conspecific and heterospecific signals is a key element in the evolution of specific mate recognition systems. Lepidopteran pheromone signals are typically composed of several compounds that synergize attraction of conspecific and inhibit attraction of heterospecific males. Blends convey specificity, but not their single components, that are typically shared by several species. Many sex pheromones are blends of geometric or positional isomers of straight-chain acetates, while species-specific blends of analogous alcohols have not been described. We have, therefore, studied the attraction of tortricid moths to the geometric isomers (E,E)-, (E,Z)-, (Z,E)- and (Z,Z)-8,10-dodecadien-1-ol. Only one species responding to these alcohols seemed to be attracted to a blend of two isomers, while most species are attracted to only one alcohol isomer. Lack of a pronounced synergist or antagonist effect of the other geometric isomers explains the lack of specific attraction to isomer blends and reduces accordingly the number of specific communication signals composed of these alcohols. In comparison, many more species respond to the analogous (E,E)-, (E,Z)-, (Z,E)- and (Z,Z)-8,10-dodecadienyl acetates and their binary blends. The acetate isomers all play a behavioural role, either as attractants, attraction synergists or antagonists, and thus promote specific communication with acetate blends. Male moths seem to discriminate the acetate isomers with greater precision than the analogous alcohols. It is proposed that discrimination is facilitated by steric differences between the four acetate isomers, as compared to the more uniform steric properties of the alcohols.
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