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- Kännaste, Astrid, et al.
(författare)
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Volatiles from a Mite-Infested Spruce Clone and Their Effects on Pine Weevil Behavior
- 2009
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Ingår i: Journal of Chemical Ecology. - : Springer Science and Business Media LLC. - 0098-0331 .- 1573-1561. ; 35:10, s. 1262-1271
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Tidskriftsartikel (refereegranskat)abstract
- Induced responses by Norway spruce (Picea abies) seedlings to feeding damage by two mite species were studied by analyzing the volatiles emitted during infestation. Four specimens of a Norway spruce (Picea abies L.) clone were infested with mites of Nalepella sp., another four with Oligonychus ununguis, and four were kept mite-free as controls. After a year of infestation, spruce volatiles were collected, analyzed, and identified using SPME-GC-MS. In addition, enantiomers of chiral limonene and linalool were separated by two-dimensional GC. Methyl salicylate (MeSA), (-)-linalool, (E)-beta-farnesene, and (E,E)-alpha-farnesene were the main volatiles induced by both species of mites, albeit in different proportions. The ability of the main compounds emitted by the mite-infested spruces to attract or repel the pine weevil, Hylobius abietis (L.), was tested. (E)-beta-farnesene was found to be attractive in the absence of spruce odor, whereas methyl salicylate had a deterrent effect in combination with attractive spruce odor. The other tested compounds had no significant effects on the behavior of the weevils.
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| 2. |
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| 3. |
- Sunnerheim, Kerstin, et al.
(författare)
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Quantitative structure-activity relationships of pine weevil antifeedants, a Multivariate approach
- 2007
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Ingår i: Journal of Agricultural and Food Chemistry. - : American Chemical Society (ACS). - 0021-8561 .- 1520-5118. ; 55:23, s. 9365-9372
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Tidskriftsartikel (refereegranskat)abstract
- Antifeedant activity of mainly phenylpropanoic, cinnamic, and benzoic acids esters was tested on the pine weevil, Hylobius abiefis (L.). Of 105 compounds screened for activity, 9 phenylpropanoates, 3 cinnamates, and 4 benzoates were found to be highly active antifeeclants. To understand the structure-activity relationships of these compounds, a multivariate analysis study was performed. A number of molecular and substituent descriptors were calculated and correlated to results from two-choice feeding tests with H. abietis. Three local models were developed that had good internal predictive ability. External test sets showed moderate predictivity. In general, low polarity, small size, and high lipophilicity were characteristics for compounds having good antifeeclant activity.
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| 4. |
- Unelius, Rikard, et al.
(författare)
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Structure-activity relationships of benzoic acid derivatives as antifeedants for the pine weevil, Hylobius abietis
- 2006
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Ingår i: Journal of Chemical Ecology. - : Springer Science and Business Media LLC. - 0098-0331 .- 1573-1561. ; 32:10, s. 2191-2203
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Tidskriftsartikel (refereegranskat)abstract
- Aromatic organic compounds found in the feces of the pine weevil, Hylobius abietis (L.) (Coleoptera: Curculionidae), have been shown to deter feeding behavior in this species, which is a serious pest of planted conifer seedlings in Europe. We evaluated 55 benzoic acid derivatives and a few homologs as antifeedants for H. abietis. Structure-activity relationships were identified by bioassaying related compounds obtained by rational syntheses of functional group analogs and structural isomers. We identified five main criteria of efficiency as antifeedants among the benzoic acid derivatives. By predicting optimal structures for H. abietis antifeedants, we attempted to find a commercial antifeedant to protect conifer seedlings against damage by H. abietis in regenerating forests. New, highly effective antifeedants are methyl 2,4-dimethoxybenzoate, isopropyl 2,4-dimethoxybenzoate, methyl 2-hydroxy-3-methoxybenzoate, methyl (3,5-dimethoxyphenyl)acetate, and methyl (2,5-dimethoxyphenyl)acetate. Of these, methyl 2,4-dimethoxybenzoate and isopropyl 2,4-dimethoxybenzoate have the highest antifeedant indices of all substances tested and are the best candidates for practical applications in order to protect planted seedlings in the field.
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