1. |
- Coracini, M., et al.
(author)
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Attraction of codling moth males to apple volatiles
- 2004
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In: Entomologia Experimentalis et Applicata. - : Wiley. - 0013-8703 .- 1570-7458. ; 110:1, s. 1-10
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Journal article (peer-reviewed)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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2. |
- Månsson, P. E., et al.
(author)
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Nonanoic acid, other alkanoic acids and related compounds as antifeedants in Hylobius abietis pine weevils
- 2006
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In: Entomologia Experimentalis et Applicata. - : Wiley. - 0013-8703 .- 1570-7458. ; 121:3, s. 191-201
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Journal article (peer-reviewed)abstract
- A medium-length, straight-chain alkanoic acid, nonanoic acid, is known from laboratory microassays to be an antifeedant in adults of the large pine weevil, Hylobius abietis (L.) (Coleoptera: Curculionidae). Our hypothesis was that we could find new, less volatile alkanoic acids or related compounds suitable for field application and with improved long-term duration. Alkanoic acids of varying chain lengths (C6-C13) were tested for antifeedant activity in H. abietis adults. Microassay choice tests showed that straight-chain (C6-C11) alkanoic acids were active. However, high activities were restricted to the (C6-C10) acids, with the C9 (nonanoic acid) at 4 μmol cm-2 being the most active one. In a no-choice test on pine twigs, the antifeedant effect of C10 acid was lower than that of the C8 and C9 acids. In microassays, less volatile methyl-branched alkanoic acids exhibited lower antifeedant activities than did the corresponding straight-chain ones. However, the most active of the methyl-branched acids, 2-methyldecanoic acid, had an activity similar to that of nonanoic acid. Compounds related to nonanoic acid were either active (1-nonanol), weakly active (nonanoic anhydride), or inactive (nonanal, sodium nonanoate). The anhydride was highly active in the microassay, but less active on twigs. The antifeedant effects of the straight chain (C8-C10) alkanoic acids against pine weevil feeding were tested in the field. In contrast to the results from the twig tests, the less volatile C10 acid was more active in the field for the protection of transplants on fresh clear cuts over a 3-month period than both the C8 and C9 acids. Phytotoxic effects of the alkanoic acids were observed both in the field and in laboratory studies. If a protective layer of paraffin was applied to the stem prior to application of the alkanoic acids, these undesired side effects were reduced.
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3. |
- Månsson, Per E., et al.
(author)
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Nonanoic acid, other long-chain carboxylic acids and related compounds as antifeedants in Hylobius abietis pine weevils
- 2006
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In: Entomologia Experimentalis et Applicata. - : Wiley. - 0013-8703 .- 1570-7458. ; 121:3, s. 191-201
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Journal article (peer-reviewed)abstract
- A medium-length, straight-chain alkanoic acid, nonanoic acid, is known from laboratory microassays to be an antifeedant in adults of the large pine weevil, Hylobius abietis (L.) (Coleoptera: Curculionidae). Our hypothesis was that we could find new, less volatile alkanoic acids or related compounds suitable for field application and with improved long-term duration. Alkanoic acids of varying chain lengths (C6-C13) were tested for antifeedant activity in H. abietis adults. Microassay choice tests showed that straight-chain (C6-C11) alkanoic acids were active. However, high activities were restricted to the (C6-C10) acids, with the C9 (nonanoic acid) at 4 mu mol cm(-2) being the most active one. In a no-choice test on pine twigs, the antifeedant effect of C10 acid was lower than that of the C8 and C9 acids. In microassays, less volatile methyl-branched alkanoic acids exhibited lower antifeedant activities than did the corresponding straight-chain ones. However, the most active of the methyl-branched acids, 2-methyldecanoic acid, had an activity similar to that of nonanoic acid. Compounds related to nonanoic acid were either active (1-nonanol), weakly active (nonanoic anhydride), or inactive (nonanal, sodium nonanoate). The anhydride was highly active in the microassay, but less active on twigs. The antifeedant effects of the straight chain (C8-C10) alkanoic acids against pine weevil feeding were tested in the field. In contrast to the results from the twig tests, the less volatile C10 acid was more active in the field for the protection of transplants on fresh clear cuts over a 3-month period than both the C8 and C9 acids. Phytotoxic effects of the alkanoic acids were observed both in the field and in laboratory studies. If a protective layer of paraffin was applied to the stem prior to application of the alkanoic acids, these undesired side effects were reduced.
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4. |
- Anderbrant, O.
(author)
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A model for the temperature and density dependent reemergence of the bark beetle Ips typographus
- 1986
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In: Entomologia Experimentalis et Applicata. - : Wiley. - 0013-8703. ; 40:1, s. 81-88
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Journal article (peer-reviewed)abstract
- A model is presented that describes the reemergence of parent spruce bark beetles, Ips typographus, based on breeding density and temperature conditions. Laboratory data obtained at one constant temperature provide the distribution of reemergence time and different combinations of threshold temperatures and degreedays (°D) at mean reemergence. Of these combinations, 167.71 °D above 7.5 °C gave the best correspondence between model prediction and field data obtained from densely infested standing trees. The model was in good agreement with the reemergence pattern found for two groups of infested logs under different temperature conditions when adjusted for the lower breeding density. The applicability of the model in the study of bark beetle reproductive biology and in forest management is discussed. The method used to construct the model should be useful in developing other models for poikilothermic processes. Modèle déconivant la réémergence d'Ips typographus en fonction de la température et de la densité Ce modèle décrit la réémergence d'adultes d'I. typographus L. (Coleoptera, Scolytidae) en fonction de la densité et de la température. Les résultats obtenus en laboratoire à des températures constantes fournissent la distribution des réémergences et pour les dates de réémergence moyenne les différentes combinaisons de température de seuil et de degré de jour (°D). De toutes ces combinaisons, 167.71 °D au‐dessus de 7,5 °C fournit la meilleure concordance entre les prévisions du modèle et les observations dans la nature à partir d'arbres fortement attaqués. Le modèle a montré un bon accord avec la réémergence observée dans deux groupes de branches attaquées dans différentes conditions de la température quand il a été ajusté aux faibles densités d'élevage. La discussion examine les possibilités d'application du modèle à l'étude de la biologie de la reproduction d'I. typographus et à l'aménagement forestier. La méthode utilisée pour construire le modèle pourrait être employée pour en développer d'autres chez des poikilothermes. 1986 The Netherlands Entomological Society
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6. |
- Anderbrant, Olle, et al.
(author)
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Development of mating disruption for control of pine sawfly populations
- 1995
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In: Entomologia Experimentalis et Applicata. - : Wiley. - 0013-8703. ; 74:1, s. 83-90
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Journal article (peer-reviewed)abstract
- Mating disruption of the pine sawfly Neodiprion sertifer (Geoffroy) (Hymenoptera: Diprionidae) was strongly indicated by reduced male trap catches in pine plantations permeated with the sex pheromone, (2S, 3S, 7S)‐diprionyl acetate. The trap catch reduction was 95 to near 100% when dispensers every 10 m were used, giving a total release of about 3 mg per hectare and day. Two mg of pheromone per cotton roll dispenser maintained low catches for the whole season (about 2 months) without any renewal of disruption dispensers. An erythro‐mixture was as effective as the pure pheromone isomer. The effects of the experiments on population density and sex ratio were not possible to investigate, due to a general collapse of the population, also outside experimental plots, the year after the experiments. 1995 The Netherlands Entomological Society
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8. |
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9. |
- Anderbrant, Olle, et al.
(author)
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Field response of the pine sawfly Neodiprion sertifer to the pheromone (2S, 3S, 7S)‐diprionyl acetate and its stereoisomers
- 1992
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In: Entomologia Experimentalis et Applicata. - : Wiley. - 0013-8703. ; 62:2, s. 169-181
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Journal article (peer-reviewed)abstract
- All eight optical isomers of 3,7‐dimethyl‐2‐pentadecanyl acetate (diprionyl acetate), of high optical purity (>97.4%), were tested for a behavioural activity on male pine sawflies, Neodiprion sertifer (Geoffr.) (Hymenoptera: Diprionidae), in northern Europe. Males were strongly attracted to (2S, 3S, 7S)‐diprionyl acetate. Addition of more than 0.1% of the (2S, 3R, 7R)‐isomer reduced the catch and above 2% the attraction was completely inhibited. Contrary to what has been reported for North American and Japanese populations, so significant synergistic effect of small amounts of the (2S, 3R, 7R)‐isomer could be demonstrated. The effects of addition of the other six optical isomers alone or in combinations, were also studied, but none was found to be a synergist. The (2S, 3R, 7S)‐isomer had a weak inhibitory effect, and completely inhibited the attraction to the (2S, 3S, 7S)‐isomer when applied in about equal amounts as the attractant. In some cases a reduction in catch was noted when other isomers were tested, but this could be attributed to the very small amounts of the inhibitory (2S, 3R, 7R)‐isomer present in these isomers. 1992 The Netherlands Entomological Society
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10. |
- Anderbrant, Olle, et al.
(author)
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Geographic variation in the field response of male European pine sawflies, Neodiprion sertifer , to different pheromone stereoisomers and esters
- 2000
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In: Entomologia Experimentalis et Applicata. - : Wiley. - 1570-7458 .- 0013-8703. ; 95:3, s. 229-239
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Journal article (peer-reviewed)abstract
- The European pine sawfly, Neodiprion sertifer (Geoffroy) (Hymenoptera: Diprionidae), is a widespread and economically important forest insect. The sex pheromone communication system of this species has been previously investigated in North America, Japan and Europe, with the acetate or propionate of the alcohol (2S,3S,7S)-3,7-dimethyl-2-pentadecanol (diprionol) shown to be the main pheromone component. In some locations, male attraction either increased or decreased by the addition of the (2S,3R,7R)-diprionyl acetate isomer. However, these studies were made with different batches of synthetic pheromones, with different types of traps and according to different procedures, so the observed differences might not reflect true geographic variation. Here we investigate the geographic pattern of male sawfly response by using identical chemicals, traps and experimental procedures at eight field sites ranging from Japan in the east to Canada in the west. We found an increased inhibitory effect of the (2S,3R,7R)-isomer from Japan and Siberia to Europe. At the eastern sites, increasing amounts of the (2S,3R,7R)-isomer up to and equal to the amount of the (2S,3S,7S )-isomer, did not influence the trap catch, whereas at sites in Europe, as little as 1% of the (2S,3R,7R)-isomer almost completely inhibited the attraction. The response of the North American population was intermediate. The only site in which the (2S,3R,7R)-isomer was essential for the attraction of males was in Siberia. A similar pattern was found for the (2S,3R,7S)-isomer. Both the acetate and the propionate form of the (2S,3S,7S)-isomer were attractive by themselves in Japan, Europe and North America, and neither the (2S,3R,7S)-isomer nor the (2S,3R,7R)-isomer alone were attractive, in the acetate or propionate form. We discuss the significance of our findings for the development of more efficient monitoring schemes and for the causes of population divergence and speciation in the European pine sawfly.
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