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1.
  • Anderbrant, Olle, et al. (author)
  • Field Response of Male Pine Sawflies, Neodiprion sertifer (Diprionidae), to Sex Pheromone Analogs in Japan and Sweden
  • 2010
  • In: Journal of Chemical Ecology. - : Springer Science and Business Media LLC. - 0098-0331 .- 1573-1561. ; 36:9, s. 969-977
  • Journal article (peer-reviewed)abstract
    • The pine sawfly Neodiprion sertifer (Geoffroy) uses the acetate or propionate of (2S,3S,7S)-3,7-dimethyl-2-pentadecanol (diprionol) as pheromone components, with the (2S,3R,7R)-isomer being antagonistic, synergistic, or inactive according to the population tested. In this study, we tested the attraction of males to the acetates of three analogs of diprionol, each missing one methyl group, viz. (2S,7S)-7-methyl-2-pentadecanol, (2S,6S)-2,6-dimethyl-1-tetradecanol, and (2S,3S)-3-methyl-2-pentadecanol. None of the analogs alone, or in combination with diprionol acetate, was attractive in Sweden, even at 100 times the amount of diprionol acetate attractive to N. sertifer. In Japan, the acetate of (2S,3S)-3-methyl-2-pentadecanol attracted males when tested in amounts 10–20 times higher than the acetate pheromone component. The acetate esters of the (2S,3R)-analog and the (2S,3R,7R)-isomer of diprionol also were tested in combination with the pheromone compound (acetate ester). Both compounds caused an almost total trap-catch reduction in Sweden, whereas in Japan they appear to have relatively little effect on trap capture when added to diprionol acetate. Butyrate and iso-butyrate esters of diprionol were unattractive to N. sertifer in Sweden. In summary, there exists geographic variation in N. sertifer in responses to both diprionyl acetate and some of its analogs.
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2.
  • Bång, Joakim (author)
  • Purification, Stereoisomeric Analysis and Quantification of Biologically Active Compounds in Extracts from Pine Sawflies, African Butterflies and Orchid Bees
  • 2011
  • Doctoral thesis (other academic/artistic)abstract
    • Stereochemistry plays an important role in nature because biologically important molecules such as amino acids, nucleotides and sugars, only exist in enantiomerically pure forms. Semiochemicals carry messages, between the same species (pheromones) and between different species (allelochemicals). Both pheromones and allelochemicals can be used as environmentally friendly pest management. Many semiochemicals, i.e. behaviour modifying chemicals, consist of pure or well-defined mixtures of stereoisomers, where some of the other stereoisomers can be repellent. It is therefore important to be able to separate them to produce a synthetic pheromone in a mixture that is attractive.Pine sawflies are a family of insects that in some cases can be severe defoliators of conifer trees. Diprion pini, Diprion similis and Neodiprion sertifer are severe pests for these trees and have got the most attention in pine sawfly pheromone studies. The pheromone precursors are stored in the female body as long-chain secondary alcohols, which, when released, are esterified to acetates or propionates. The alcohols are chiral, and normally one of the stereoisomer is the main pheromone component, sometimes possible together with other stereoisomers as essential minor components.Bicyclus is a genus of African butterflies, and especially Bicyclus anynana has become a popular model for the study of life history evolution, morphology, mating choice and genetics. The wing pattern of Bicyclus differs depending on the season, with large eyespots during the rain-season and small or absent spots during the dry season. Euglossa is one of the genera among the orchid bees in the Neotropics that does not produce its own pheromone. Instead, the males collect fragrances from orchids and other sources and store them in a pocket in their hind legs. Both Bicyclus and Euglossa use semiochemicals similar to pine sawflies, and thus can be analysed by the same methods.Pheromones and other semiochemicals in insects are often present in low amounts in a complex matrix, and purification of the sample before chemical analysis is often required. A common method is gradient elution on a solid phase silica column. Separation of stereoisomers can be achieved either by using a column with a chiral stationary phase (CSP) or with pre-column derivatisation using a column with an achiral stationary phase (ASP) or a combination of both, with mass detection as the dominant detection method. The purpose of this work has been to improve the purification method, find suitable methods to separate the stereoisomers of secondary alcohols, and to apply this on extracts of insects.By selecting the right fractions to collect during gradient elution the purification method was optimised. To reduce plasticizer contamination from ordinary columns, solid phase columns of Teflon or glass were used. For pre-column derivatisation of different chiral alcohols various acid chlorides were tested. For the pine sawfly pheromone precursors enantiopure (2S)-2-acetoxypropionyl chloride was the best choice. To separate some of the stereoisomers achiral 2-naphthoyl chloride was used. For derivatisation of 6,10,14-trimethylpentadecan-2-ol (R)-trans-chrysanthemoyl chloride was the best choice. The derivatised alcohols were separated on different columns, both chiral and non-chiral. Varian FactorFour VF-23ms was chosen as a general-purpose column, the Agilent HP-88 column was the best column with an ASP of those tested, and the Chiraldex B-PA column (CSP) was the only one that could separate all eight stereoisomers of derivatised 3,7-dimethylundecan-2-ol, 3,7-dimethyldodecan-2-ol, and 3,7-dimethyltridecan-2-ol.To determine the stereoisomeric purity of standard solutions used in field experiments and extracts of different species of insects the optimised methods were applied. For extracts from B. anynana, Euglossa and Neodiprion lecontei this work describe the first determination of the stereochemistry of some of their semiochemicals.For the determination of the stereochemistry of chiral semiochemicals the methods for purification and separation presented herein have shown to be of great value. The results will hopefully contribute to a better understanding of the communication among insects, and ultimately to a more environmentally friendly pest control.
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4.
  • Andersson, K., et al. (author)
  • High-accuracy sampling of saproxylic diversity indicators at regional scales with pheromones : The case of Elater ferrugineus (Coleoptera, Elateridae)
  • 2014
  • In: Biological Conservation. - : Elsevier BV. - 0006-3207 .- 1873-2917. ; 171, s. 156-166
  • Journal article (peer-reviewed)abstract
    • The rare beetle Elater ferrugineus was sampled at 47 sites in the county of Östergötland, Sweden by means of pheromone-baited traps to assess its value as an indicator species for hollow oak stands rich in rare saproxylic beetle species. In addition, Osmoderma eremita was also sampled with pheromone baits. These data were then compared against species survey data collected at the same sites by pitfall and window traps. Both species co-occur with many Red Listed saproxylic beetles, with E. ferrugineus being a somewhat better indicator for the rarest species. The conservation value of a site (measured as Red List points or number of Red Listed species) increased with the number of specimens of E. ferrugineus and O. eremita caught. Accuracy of sampling by means of pheromone trapping turned out to be radically different for the two model species. E. ferrugineus traps put out during July obtained full accuracy after only 6. days, whereas O. eremita traps needed to be out from early July to mid-August in order to obtain full accuracy with one trap per site. By using E. ferrugineus, or preferably both species, as indicator species, accuracy would increase and costs decrease for saproxylic biodiversity sampling, monitoring and identification of hotspots. © 2014 Elsevier Ltd.
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5.
  • Barup, Kerstin, et al. (author)
  • Multi-disciplinary lidar applications
  • 2010
  • In: Laser Applications to Chemical, Security and Environmental Analysis, LACSEA 2010. - 2162-2701. - 9781557528803
  • Conference paper (peer-reviewed)abstract
    • Lidar is a powerful technique normally associated with atmospheric monitoring. However, lidar techniques, also of the laser-induced fluorescence and laser-induced breakdown spectroscopy varieties, provide many new possibilities in unconventional fields including cultural heritage and ecological applications.
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6.
  • Boija, Susanne, et al. (author)
  • Determination of conditional stability constants for some divalent transition metal ion-EDTA complexes by electrospray ionization mass spectrometry
  • 2014
  • In: Journal of Mass Spectrometry. - : Wiley. - 1076-5174 .- 1096-9888. ; 49:7, s. 550-556
  • Journal article (peer-reviewed)abstract
    • Conditional stability constants of coordination complexes comprising divalent transition metals, Cu2+, Ni2+, Zn2+, Co2+, and ethylenediaminetetraacetic acid (EDTA) were determined utilizing electrospray ionization mass spectrometry. The deviation of signal response of a reference complex was monitored at addition of a second metal ion. The conditional stability constant for the competing metal was then determined through solution equilibria equations. The method showed to be applicable to a system where Co2+ and Zn2+ competed for EDTA at pH 5. When Cu2+ and Ni2+ competed for EDTA, the equilibrium changed over time. This change was shown to be affected in rate and size by the type of organic solvent added. In this work, 30% of either methanol or acetonitrile was used. It was found that if calibration curves are prepared for both metal complexes in solution and the measurements are repeated with sufficient time space, any change in equilibrium of sample solutions will be discovered. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.
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8.
  • Bång, Joakim, et al. (author)
  • Purification, Stereoisomeric Analysis and Quantification of Sex Pheromone Precursors in Female Whole Body Extracts from Pine Sawfly Species
  • 2011
  • In: Journal of Chemical Ecology. - : Springer Science and Business Media LLC. - 0098-0331 .- 1573-1561. ; 37:1, s. 125-133
  • Journal article (peer-reviewed)abstract
    • A GC-MS method to analyze the stereoisomeric composition of chiral secondary alcohols found in whole body extracts of pine sawfly females was developed. The tested alcohols were derivatized with optically pure (S)-2-acetoxypropionyl chloride prior to GC-MS analysis. Baseline separation was obtained for all sixteen stereoisomers of 3,7,9-trimethyltridecan-2-ol and for the four 3-methylpentadecan-2-ol stereoisomers. For 3,7-dimethyltridecan-2-ol, 3,7-dimethyltetradecan-2-ol and 3,7-dimethylpentadecan-2-ol baseline separation was obtained for 6 of the possible 8 stereoisomers. When a mixture of 16 stereoisomers of 3,7,11-trimethyltridecan-2-ol was tested, baseline separation of 7 peaks out of 16 possible was obtained. The investigated alcohols are pheromone precursors for some pine sawfly species that are severe defoliators of pine. Females from several Diprion, Neodiprion, Macrodiprion, Microdiprion, and Gilpinia species emit esters of such secondary alcohols as sex pheromones that attract males for mating. To quantify the small amounts of the precursor alcohol and its stereoisomeric composition found in whole body extracts from female pine sawflies, a purification method was optimized. An extract of 20 females of D. pini contained about 8 ng of (2 S,3 R,7 R)-3,7-dimethyltridecan-2-ol per female, and three extracts of 18, 20, and 90 females of N. sertifer contained between 5 and 13 ng of (2 S,3 S,7 S)-3,7-dimethylpentadecan-2-ol per female.
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9.
  • Bång, Joakim, et al. (author)
  • Stereoisomeric separation of derivatised 2-alkanols using gas chromatography – mass spectrometry: sex pheromone precursors found in pine sawfly species
  • 2012
  • In: Analytical Letters. - : Informa UK Limited. - 0003-2719 .- 1532-236X. ; 45:9, s. 1016-1027
  • Journal article (peer-reviewed)abstract
    • Abstract in UndeterminedStereoisomers of long-chain secondary alcohols are used as sex pheromone precursors among pine sawflies and some species can be severe pine forest pests. To use their pheromone in environmentally friendly pest management, methods are needed that can determine the stereochemistry of the precursor alcohols. Combinations of 11 acid chloride derivatives and 10 GC columns were evaluated for separation of stereoisomers of 3,7-dimethylundecan-2-ol, 3,7-dimethyldodecan-2-ol, 3,7-dimethyltridecan-2-ol, 3,7-dimethyltetradecan-2-ol, and 3,7-dimethylpentadecan-2-ol. Derivatization with (S)-2-acetoxypropionyl chloride in combination with a Chiraldex B-PA column separated all eight stereoisomers of 3,7dimethylundecan-2-ol, 3,7-dimethyldodecan-2-ol, and 3,7-dimethyltridecan-2-ol. A combination of two different derivatization methods was needed to separate all stereoisomers of the longer chained alcohols 3,7-dimethyltetradecan-2-ol and 3,7-dimethylpentadecan-2-ol. A female extract of the pine sawfly Neodiprion lecontei was also analyzed and the stereochemistry of the sex pheromone alcohol precursor was determined to be (2S,3S,7S)-3,7-dimethylpentadecan-2-ol at an amount of about 7 ng/female. This paper presents the first GC-MS separation of all eight stereoisomers of 3,7-dimethylundecan-2-ol, 3,7dimethyldodecan-2-ol, and 3,7-dimethyltridecan-2-ol in a single analytical run and also the first GC-MS determination of the stereochemistry of the sex pheromone precursor found in females of N. lecontei.
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12.
  • Eltz, Thomas, et al. (author)
  • (6R,10R)-6,10,14-Trimethylpentadecan-2-one, a Dominant and Behaviorally Active Component in Male Orchid Bee Fragrances
  • 2010
  • In: Journal of Chemical Ecology. - : Springer Science and Business Media LLC. - 0098-0331 .- 1573-1561. ; 36:12, s. 1322-1326
  • Journal article (peer-reviewed)abstract
    • 6,10,14-Trimethylpentadecan-2-one (Hexahydrofarnesyl acetone; HHA) previously has been found to be a major component in tibial fragrances of male orchid bees, Euglossa spp. HHA is a chiral molecule with four possible stereoisomers, (6R,10R)-, (6R,10S)-, (6S,10R)-, and (6S,10S)-6,10,14-trimethylpentadecan-2-one. In the present study, we characterized HHA extracted from Euglossa as the pure enantiomer (6R,10R)-6,10,14-trimethylpentadecan-2-one. During bioassays in Mexico and Panama, the synthetic RR-isomer attracted males of six species of orchid bees, including three that were known to contain HHA in their tibial fragrances. Possible sources of HHA for wild bees are flowers of euglossophilous orchids and aroids. With a molecular weight of 268, HHA is the largest natural molecule known to attract male orchid bees in pure form. Its attractiveness to males suggests that low-volatility compounds have a function in male signals, e.g., serve as a "base note" in complex odor bouquets. © 2010 Springer Science+Business Media, LLC.
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13.
  • Fagerlund-Edfeldt, Amelie, et al. (author)
  • Effect of Debarking Water from Norway Spruce (Picea abies) on the Growth of Five Species of Wood-Decaying Fungi
  • 2014
  • In: Zeitschrift für Naturforschung C - A Journal of Biosciences. - 0939-5075 .- 1865-7125. ; 9-10:69c, s. 418-424
  • Journal article (peer-reviewed)abstract
    • Norway spruce (Picea abies) debarking water is an aqueous extract obtained as waste from the debarking of logs at paper mills. The debarking water contains a mixture of natural compounds that can exhibit diverse biological activities, potentially including fungicidal activity on some species of wood-decaying fungi. Thus, we investigated the growth rates of such fungi on agar plates to which debarking water extracts had been added. The experiment included five wood-decaying fungi, viz. Gloeophyllum sepiarium, Oligoporus lateritius, Ischnoderma benzoinum, Junghuhnia luteoalba, and Phlebia sp. Growth reduction was observed for all species at the highest tested concentrations of freeze-dried and ethanol-extracted debarking water, the ethyl acetate-soluble fraction and the diethyl ether-soluble fraction. However, the magnitude of the effect varied between different species and strains of individual species. The brown-rot fungi G. sepiarium and O. lateritius were generally the most sensitive species, with the growth of all tested strains being completely inhibited by the ethyl acetate-soluble fraction. These results indicate that development of antifungal wood-protecting agents from debarking water could potentially be a way to make use of a low-value industrial waste.
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15.
  • Hagström, Åsa, et al. (author)
  • Semi-selective fatty acyl reductases from four Heliothine moths influence the specific pheromone composition
  • 2012
  • In: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 7:e37230, s. 1-11
  • Journal article (peer-reviewed)abstract
    • Background: Sex pheromones are essential in moth mate communication. Information on pheromone biosynthetic genes and enzymes is needed to comprehend the mechanisms that contribute to specificity of pheromone signals. Most heliothine moths use sex pheromones with (Z)–11–hexadecenal as the major component in combination with minor fatty aldehydes and alcohols. In this study we focus on four closely related species, Heliothis virescens, Heliothis subflexa, Helicoverpa armigera and Helicoverpa assulta, which use (Z)–11–hexadecenal, (Z)–9–tetradecanal, and (Z)–9–hexadecenal in different ratios in their pheromone blend. The components are produced from saturated fatty acid precursors by desaturation, b–oxidation, reduction and oxidation. Results: We analyzed the composition of fatty acyl pheromone precursors and correlated it to the pheromone composition. Next, we investigated whether the downstream fatty–acyl reduction step modulates the ratio of alcohol intermediates before the final oxidation step. By isolating and functionally characterizing the Fatty Acyl Reductase (pgFAR) from each species we found that the pgFARs were active on a broad set of C8 to C16 fatty acyl substrates including the key pheromone precursors, Z9–14, Z9–16 and Z11–16:acyls. When presenting the three precursors in equal ratios to yeast cultures expressing any of the four pgFARs, all reduced (Z)–9–tetradecenoate preferentially over (Z)–11–hexadecenoate, and the latter over (Z)–9–hexadecenoate. Finally, when manipulating the precursor ratios in vitro, we found that the pgFARs display small differences in the biochemical activity on various substrates. Conclusions: We conclude that a pgFAR with broad specificity is involved in heliothine moth pheromone biosynthesis, functioning as a semi–selective funnel that produces species–specific alcohol product ratios depending on the fatty–acyl precursor ratio in the pheromone gland. This study further supports the key role of these in pheromone biosynthesis and emphasizes the interplay between the pheromone fatty acyl precursors and the Lepidoptera specific pgFARs in shaping the pheromone composition.
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16.
  • Högberg, Ida, et al. (author)
  • Brightness development of a hydrogen peroxide bleached spruce TMP. Comparisons of pre-treatments with DTPA and a separable chelating surfactant
  • 2012
  • In: Nordic Pulp & Paper Research Journal. - 0283-2631 .- 2000-0669. ; 27:1, s. 50-55
  • Journal article (peer-reviewed)abstract
    • In this investigation a new type of recoverable complexing agent (chelating surfactant) has been compared with a conventional complexing agent; diethylenetriamine pentaacetic acid (DTPA), in the metal ion sequestering of thermomechanical pulps (TMP) to be hydrogen peroxide bleached. After different degrees of washing of the pulps, bleaching experiments at different total alkali charges were performed with and without sodium silicate additions, and the ISO brightness of hand-made sheets was measured. The residual hydrogen peroxide in the bleaching liquor was also determined. No significant difference in either the brightness development or the residual hydrogen peroxide content could be detected between the pulps treated with equivalent molar ratios of the different complexing agents. Furthermore, the recovery of the chelating surfactant-manganese complexes from laboratory made white water by froth flotation was also studied. Two different foaming agents; sodium dodecyl sulphonate (SDS) and dimethyldodecylamine oxide (DDAO), were tested in the froth generation. After an addition of 160 ppm of DDAO, more than 80% of the manganese chelates could be recovered in the foam, containing 3% of the initial water mass.
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17.
  • Högberg, Ida, et al. (author)
  • The Interaction Parameter in Binary Surfactant Mixtures of a Chelating Surfactant and a Foaming Agent.
  • 2010. - 138
  • In: TRENDS IN COLLOID AND INTERFACE SCIENCE XXIV. - Berlin : Springer. - 9783642190377 ; , s. 17-20
  • Conference paper (peer-reviewed)abstract
    • The micellisation in binary mixed surfactant systems of a chelating surfactant and a foaming agent has been studied by surface tension measurements in order to calculate the interaction parameter (beta). 2-dodecyldiethylenetriamine pentaacetic acid, 4-C(12)-DTPA, is an amphoteric chelating surfactant applicable for removing disturbing metal ions from industrial processes, or for heavy metal decontamination of soil or leachate. 4-C(12)-DTPA contains multiple donor atoms and forms very stable coordination complexes with metal ions. The metal complexes can easily be recovered from water by flotation, if the foaming is enhanced by a foaming agent with strong interactions to the chelating surfactant. Two foaming agents were examined, one cationic and one anionic. As expected, strong interactions were found between the negatively charged 4-C(12)-DTPA and the cationic dodecyltrimethylammonium chloride, DTAC. The influence of metal ion chelation, as well as pH, on the interaction parameter was also investigated.
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18.
  • Högberg, Ida, et al. (author)
  • Use of chelating surfactants as complexing agents for removal of manganese from mechanical pulp fibres prior to hydrogen peroxide bleaching.
  • 2011
  • In: 16th International Symposium on Wood, Fiber and Pulping Chemistry - Proceedings, ISWFPC. - Tianjin : China Light Industry Press. ; , s. 682-686
  • Conference paper (peer-reviewed)abstract
    • In this investigation a new type of recoverable complexing agent (chelating surfactant) has been compared with a conventional complexing agent (DTPA) in the metal ion management of thermomechanical pulps (TMP) to be hydrogen peroxide bleached. After different degrees of washing of the pulps, bleaching experiments at different total alkali charges were performed with and without sodium silicate additions, and the ISO brightness of hand-made sheets was measured. The residual hydrogen peroxide in the bleaching liquor was also determined. No significant difference in either the brightness development or the residual hydrogen peroxide content could be detected between the pulps treated with equivalent molar ratios of the different complexing agents. Furthermore, the recovery of the surfactant-manganese complexes from laboratory made white water by foam flotation was also studied. Two different foaming agents, SDS and DDAO, were tested. After an addition of 160 ppm of the latter surfactant, about 80% of the manganese chelates could be recovered in the foam, containing 3% of the initial water mass.
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20.
  • Karlsson, Anette, et al. (author)
  • Strategies to reduce heat-induced darkening for enhanced bleachability of mechanical pulps
  • 2014
  • In: Appita journal. - 1038-6807. ; 67:1, s. 50-57
  • Journal article (peer-reviewed)abstract
    • Under mechanical pulping conditions, elevated temperature initiates reactions in the wood constituents resulting in the formation of coloured structures. In an attempt to reduce the formation of colour, a number of additives have been examined to assess their ability to inhibit heat-induced darkening of a Norway spruce (Picea abies) stone groundwood (SGW) pulp. SGW pulp was used as a model pulp with the purpose of imitating a thermomechanical pulp (IMP). The heat-treated SGW pulp, both with and without additives present, was subsequently bleached with 4.5% hydrogen peroxide at high pulp consistency and with varying alkali charges in order to examine the hydrogen peroxide bleachability of such pulps. Heat treatment at 170 °C resulted in a loss of brightness of about 4% ISO after heating for 60 seconds. The reduction in brightness could only partly be regained through high consistency hydrogen peroxide bleaching; the SGW pulp displayed a brightness of 83.7% ISO whereas the heat-treated SGW pulp reached a brightness of 80.4% ISO. Heat treatment with a low addition rate (1 %) of alkaline hydrogen peroxide, sodium bisulfite or sodium sulfite, with a subsequent hydrogen peroxide bleaching stage, resulted in an improved bleached brightness of about 81.6% ISO, i.e. the loss of brightness due to heat was still approximately 2% ISO. Sodium borohydride (1 %) did not suppress the thermal darkening but improved the bleached brightness by approximately 2% ISO compared to the heat-treated SGW pulp and resulted in a brightness of 82.6% ISO. Addition of a chelating agent (DTPA, 0.11 and 0.45%) and the radical scavengers phthalic hydrazide (1 %) and 1 -hexanol (1 %) suppressed the heat-induced darkening somewhat but did not improve the hydrogen peroxide bleachability to any noticeable extent. Addition of citric acid (0.6%) did not suppress the thermal darkening and resulted in impaired bleachability.
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21.
  • Lassance, Jean-Marc, et al. (author)
  • Allelic variation in a fatty-acyl reductase gene causes divergence in moth sex pheromones
  • 2010
  • In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 466:7305, s. 486-489
  • Journal article (peer-reviewed)abstract
    • Pheromone-based behaviours are crucial in animals from insects to mammals, and reproductive isolation is often based on pheromone differences. However, the genetic mechanisms by which pheromone signals change during the evolution of new species are largely unknown. In the sexual communication system of moths (Insecta: Lepidoptera), females emit a species-specific pheromone blend that attracts males over long distances. The European corn borer, Ostrinia nubilalis, consists of two sex pheromone races, Z and E, that use different ratios of the cis and trans isomers of acetate pheromone components. This subtle difference leads to strong reproductive isolation in the field between the two races, which could represent a first step in speciation. Female sex pheromone production and male behavioural response are under the control of different major genes, but the identity of these genes is unknown. Here we show that allelic variation in a fatty-acyl reductase gene essential for pheromone biosynthesis accounts for the phenotypic variation in female pheromone production, leading to race-specific signals. Both the cis and trans isomers of the pheromone precursors are produced by both races, but the precursors are differentially reduced to yield opposite ratios in the final pheromone blend as a result of the substrate specificity of the enzymes encoded by the Z and E alleles. This is the first functional characterization of a gene contributing to intraspecific behavioural reproductive isolation in moths, highlighting the importance of evolutionary diversification in a lepidopteran-specific family of reductases. Accumulation of substitutions in the coding region of a single biosynthetic enzyme can produce pheromone differences resulting in reproductive isolation, with speciation as a potential end result.  
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22.
  • Liedtke, H. Christoph, et al. (author)
  • Alarm pheromones and chemical communication in nymphs of the tropical bed bug Cimex hemipterus (Hemiptera: Cimicidae)
  • 2011
  • In: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 6:3, s. e18156-
  • Journal article (peer-reviewed)abstract
    • The recent resurge of bed bug infestations (Cimex spp.; Cimicidae) and their resistance to commonly used pesticides calls for alternative methods of control. Pheromones play an important role in environmentally sustainable methods for the management of many pest insects and may therefore be applicable for the control of bed bugs. The tropical bed bug, Cimex hemipterus, is a temporary ectoparasite on humans and causes severe discomfort. Compared to the common bed bug, Cimex lectularius, little is known about the chemical signalling and pheromone-based behaviour of the tropical species. Here, we show that the antennal morphology and volatile emission of C. hemipterus closely resembles those of C. lectularius and we test their behavioural responses to conspecific odour emissions. Two major volatiles are emitted by male, female and nymph C. hemipterus under stress, (E)-2-hexenal and (E)-2-octenal. Notably, nymph emissions show contrasting ratios of these compounds to adults and are further characterized by the addition of 4-oxo-(E)-2-hexenal and 4-oxo-(E)-2-octenal. The discovery of this nymph pheromone in C. hemipterus is potentially the cause of a repellent effect observed in the biotests, where nymph odours induce a significantly stronger repellent reaction in conspecifics than adult odours. Our results suggest that pheromone-based pest control methods developed for C. lectularius could be applicable to C. hemipterus, with the unique nymph blend showing promising practical properties.
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23.
  • Musa, Najihah, et al. (author)
  • Using Sex Pheromone and a Multi-Scale Approach to Predict the Distribution of a Rare Saproxylic Beetle
  • 2013
  • In: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 8:6
  • Journal article (peer-reviewed)abstract
    • The European red click beetle, Elater ferrugineus L., is associated with wood mould in old hollow deciduous trees. As a result of severe habitat fragmentation caused by human disturbance, it is threatened throughout its distribution range. A new pheromone-based survey method, which is very efficient in detecting the species, was used in the present study to relate the occurrence of E. ferrugineus to the density of deciduous trees. The latter data were from a recently completed regional survey in SE Sweden recording >120,000 deciduous trees. The occurrence of E. ferrugineus increased with increasing amount of large hollow and large non-hollow trees in the surrounding landscape. Quercus robur (oak) was found to be the most important substrate for E. ferrugineus, whereas two groups of tree species (Carpinus betulus, Fagus sylvatica, Ulmus glabra, vs. Acer platanoides, Aesculus hippocastanum, Fraxinus excelsior, Tilia cordata) were less important but may be a complement to oak in sustaining populations of the beetle. The occurrence of E. ferrugineus was explained by the density of oaks at two different spatial scales, within the circle radii 327 m and 4658 m. In conclusion, priority should be given to oaks in conservation management of E. ferrugineus, and then to the deciduous trees in the genera listed above. Conservation planning at large spatial and temporal scales appears to be essential for long-term persistence of E. ferrugineus. We also show that occurrence models based on strategic sampling might result in pessimistic predictions. This study demonstrates how pheromone-based monitoring make insects excellent tools for sustained feedback to models for landscape conservation management.
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24.
  • Nieberding, Caroline M, et al. (author)
  • Cracking the olfactory code of a butterfly : the scent of ageing.
  • 2012
  • In: Ecology Letters. - : Wiley. - 1461-023X .- 1461-0248. ; 15:5, s. 415-424
  • Journal article (peer-reviewed)abstract
    • Ecology Letters (2012) 15: 415-424 ABSTRACT: Although olfaction is a primary mode of communication, its importance in sexual selection remains understudied. Here, using the butterfly Bicyclus anynana, we address all the parameters of importance to sexual selection for a male olfactory signal. We show that variation in the male sex pheromone composition indicates male identity and male age. Courting males of different ages display small absolute (c. 200 ng) but large relative (100%) change of one specific pheromone component (hexadecanal) which, unlike the other components, showed no heritability. Females prefer to mate with mid-aged over younger males and the pheromone composition is sufficient to determine this preference. Surprisingly refined information is thus present in the male olfactory signal and is used for sexual selection. Our data also reveal that there may be no 'lek paradox' to resolve once the precise signal of importance to females is identified, as hexadecanal is, as expected, depleted in additive genetic variation.
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25.
  • Pokorny, T., et al. (author)
  • Acquisition of species-specific perfume blends : Influence of habitat-dependent compound availability on odour choices of male orchid bees (Euglossa spp.)
  • 2013
  • In: Oecologia. - : Springer Science and Business Media LLC. - 0029-8549 .- 1432-1939. ; 172:2, s. 417-425
  • Journal article (peer-reviewed)abstract
    • Male orchid bees (Euglossini, Apidae, Hymenoptera) expose species-specific blends of volatile chemicals (perfume bouquets) during their courtship display. The perfumes are acquired by collecting fragrant substances from environmental sources, which are then accumulated in specialised hind leg pouches. To balance the perfume composition, the males need to find and collect the required substances in specific relative amounts while facing seasonal, local or habitat-dependent differences in compound availability. Experience-dependent choice of odours, i.e. 'learned avoidance' of recently collected components, has been proposed as the mechanism that mediates the accumulation of the stereotypical compound ratios. In the present study, we used the presence of certain compounds in male hind leg pouches as proxy for the respective local compound availability, and investigated whether differences in content are correlated with differences in chemical choice assays. Our results suggest that volatile availability differs between localities (n = 16) as well as habitats (n = 2; coastal vs. inland) across the Yucatán peninsula, Mexico, for both studied species. Male Euglossa dilemma showed a pronounced preference for benzyl benzoate and eugenol at locations where those compounds were rare in hind leg extracts, as predicted by the learned avoidance model. No equivalent correlations were found for Euglossa viridissima. This is the first study to combine chemical analyses of perfumes with bioassays of odour choice. It strengthens the view that negative feedback from collected odours modifies future chemical choice and helps males to acquire specific perfume blends. © 2013 Springer-Verlag Berlin Heidelberg.
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26.
  • Strand, Anders, et al. (author)
  • Selective froth flotation of pitch components from spruce TMP process water
  • 2012
  • In: Appita journal. - 1038-6807. ; 65:4, s. 337-346
  • Journal article (peer-reviewed)abstract
    • Selective removal of dissolved and colloidal pitch components from an unbleached thermomechanical pulp (TMP)pressate by addition of a cationic foaming agent, dodecyltrimethylammonium chloride (DoTAC), and subsequent frothflotation was assessed. The experiments were conducted with varying pH, temperature, and concentrations of DoTACand calcium. The concentrations of pitch components, lignans, and dissolved polysaccharides were determinedbefore and after flotation.All pitch components were removed more efficiently by flotation at pH 5 and 3.5 than by flotation at pH 7.6. Resinand fatty acids were removed to a higher degree than neutral pitch substances at all the tested pH levels. Most of thewater-soluble uronic acids and galactoglucomannans stayed in the TMP water after flotation.Froth flotation with DoTAC was an effective way of selectively removing colloidal and dissolved pitch. Removal of pitch,especially of resin acids, at an early stage should be beneficial to the overall papermaking process.
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27.
  • Svanedal, Ida, 1979-, et al. (author)
  • Metal Ion Coordination, Conditional Stability Constants and Solution Behavior of Chelating Surfactant Metal Complexes
  • 2014
  • In: Langmuir. - : American Chemical Society (ACS). - 0743-7463 .- 1520-5827. ; 30:16, s. 4605-4612
  • Journal article (peer-reviewed)abstract
    • Coordination complexes of some divalent metal ions with the DTPA (diethylenetriaminepentaacetic acid)-based chelating surfactant 2-dodecyldiethylenetriaminepentaacetic acid (4-C12-DTPA) have been examined in terms of chelation and solution behavior. The headgroup of 4-C 12-DTPA contains eight donor atoms that can participate in the coordination of a metal ion. Conditional stability constants for five transition metal complexes with 4-C12-DTPA were determined by competition measurements between 4-C12-DTPA and DTPA, using electrospray ionization mass spectrometry (ESI-MS). Small differences in the relative strength between the coordination complexes of DTPA and 4-C12-DTPA indicated that the hydrocarbon tail only affected the chelating ability of the headgroup to a limited extent. The coordination of Cu2+ ions was investigated in particular, using UV-visible spectroscopy. By constructing Job's plots, it was found that 4-C12-DTPA could coordinate up to two Cu2+ ions. Surface tension measurements and NMR diffusometry showed that the coordination of metal ions affected the solution behavior of 4-C 12-DTPA, but there were no specific trends between the studied divalent metal complexes. Generally, the effects of the metal ion coordination could be linked to the neutralization of the headgroup charge of 4-C 12-DTPA, and the resulting reduced electrostatic repulsions between adjacent surfactants in micelles and monolayers. The pH vs concentration plots, on the other hand, showed a distinct difference between 4-C12-DTPA complexes of the alkaline earth metals and the transition metals. This was explained by the difference in coordination between the two groups of metal ions, as predicted by the hard and soft acid and base (HSAB) theory.
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28.
  • Svensson, Glenn, et al. (author)
  • Chemical ecology and insect conservation: optimising pheromone-based monitoring of the threatened saproxylic click beetle Elater ferrugineus
  • 2012
  • In: Journal of Insect Conservation. - : Springer Science and Business Media LLC. - 1366-638X .- 1572-9753. ; 16:4, s. 549-555
  • Journal article (peer-reviewed)abstract
    • Elater ferrugineus is a saproxylic click beetle inhabiting old deciduous trees in Europe. It is threatened throughout its area of distribution due to habitat loss. No efficient monitoring method has been available for this species, but observed attraction of females to (R)-(+)-γ-decalactone, which is a male-produced sex pheromone of its prey, the scarab beetle Osmoderma eremita, has led to the development of an odour lure for monitoring. In addition, four esters have recently been identified from the pheromone-producing gland in female E. ferrugineus, and a blend of these esters is highly attractive to conspecific males in the field, revealing an alternative odour-based method for monitoring this species. However, no rigorous analysis has been performed to check whether all four esters show biological activity in male E. ferrugineus, and whether its own sex pheromone is a more potent lure than the prey kairomone for monitoring of E. ferrugineus. In this study, we reinvestigated the E. ferrugineus sex pheromone, using electrophysiological and behavioural analyses, and found that only one of the esters, 7-methyloctyl (Z)-4-decenoate, is active. In addition, trapping experiments revealed that 7-methyloctyl (Z)-4-decenoate is a much more efficient attractant for male E. ferrugineus than the prey pheromone is for conspecific females, or any sex of O. eremita. With a very efficient odour lure at hand, novel information about current distribution, local population sizes, and dispersal ranges in E. ferrugineus can now be obtained, which can aid in conservation efforts to protect this threatened insect and its habitat.
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29.
  • Svensson, Glenn, et al. (author)
  • Identification, Synthesis, and Behavioral Activity of 5,11-Dimethylpentacosane, A Novel Sex Pheromone Component of the Greater Wax Moth, Galleria Mellonella (L.)
  • 2014
  • In: Journal of Chemical Ecology. - : Springer Science and Business Media LLC. - 0098-0331 .- 1573-1561. ; 40:4, s. 387-395
  • Journal article (peer-reviewed)abstract
    • The greater wax moth, Galleria mellonella (L.), is a serious and widespread pest of the honeybee, Apis mellifera L. In contrast to most moths, for which long-range mate finding is mediated by female-produced sex pheromones, G. mellonella males attract conspecific females over long distances by emitting large amounts of a characteristic scent in combination with bursts of ultrasonic calls. The male scent for this species was previously identified as a blend of nonanal and undecanal. When these compounds were bioassayed, characteristic short-range sexual behavior, including wing fanning, was triggered in conspecific females, but the aldehyde blend failed to elicit attraction over longer distances. We identified, via analysis and synthesis, a third male-specific compound, 5,11-dimethylpentacosane. We show that it acts as a behavioral synergist to the aldehydes. In wind tunnel experiments, very few female moths responded to the aldehyde blend or to 5,11-dimethylpentacosane tested separately, but consistently showed orientation and source contact when a combination of all three compounds was applied. The level of attraction to the three-component mixture was still lower than that to male extract, indicating that the composition of compounds in the synthetic blend is suboptimal, or that additional pheromone components of G. mellonella are yet to be identified. The identification of 5,11-dimethylpentacosane is an important step for the development of an efficient long-range attractant that will be integrated with other environmentally safe strategies to reduce damage to beehives caused by wax moths. © 2014 Springer Science+Business Media New York.
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30.
  • Wallin, Erika, 1985- (author)
  • The Scents of Nature : Identification and Synthesis of Bioactive Compounds Used in Insect Communication
  • 2014
  • Doctoral thesis (other academic/artistic)abstract
    • Pest insects cause great financial losses in the forest and food industry every year. To fight these pests industries have used insecticides, which are sometimes harmful to nature and humans. One potential way of avoiding insecticides is the use of integrated pest management based on insect communication, which would offer species-specific methods for protecting forest and food resources. Insects use chemicals known as semiochemicals for both intra- and interspecies communication. By learning how insects use these semio-chemicals to talk to each other we can eavesdrop and mimic their communication for our benefit. One research area dealing with these questions is chemical ecology, which is an interdisciplinary area as knowledge in chemistry and biology is required. Collaborations between groups within and outside of Sweden are essential in order to make progress in this field of research.This thesis presents the identification and synthesis of semiochemicals from several insect species, most of which are considered to be pests. Synthesised compounds have been sent to collaboration partners around Sweden and Europe for biological evaluations.Studies of the African butterfly, Bicyclus anynana, have unravelled particular biological phenomena that may aid in the understanding of the Bicyclus genus, though recognizing individual species variation is crucial. In 2008 the putative male sex pheromone of B. anynana was determined to consist of three compounds: hexadecanal, (Z)-9-tetradecenol and 6,10,14-trimethylpentadecan-2-ol, and the specific stereoisomer for 6,10,14-trimethylpentadecan-2-ol has been determined in this thesis. The ratio of 6,10,14-trimethylpentadecan-2-ol and the corresponding ketone were investigated for seventeen Bicyclus species (including B. anynana) that live in overlapping regions in Africa. The stereochemistry was determined for most of the species and may provide a way to chemically distinguish them.The orchid bees, Euglossa spp, are important pollinators of many orchids in Central America. Insight about pollination and conservation of endangered orchid species may be possible by gathering more information about the Euglossa genus. Males of the Euglossa genus have pouch-like structures on their hind legs where they store compounds collected from their surroundings. 6,10,14-Trimethyl-pentadecan-2-one is a common component of leg extracts from Euglossa imperialis, E. crassipunctata and E. allosticta, the specific stereochemistry of which has been determined in this thesis. Another, different compound was found in high amounts in E. viridissima and its structure has been elucidated; several synthetic pathways are under investigation to obtain the target compound.Bed bugs (Cimex lectularius and C. hemipterus) are an ectoparasite that feed on human blood, and the number of reported infestations of these parasites has increased considerably during the last decade. Two 5th instar nymph-specific compounds, 4-oxo-hexenal and 4-oxo-octenal, were identified and synthesised.Utilizing domestic dogs (Canis lupus familiaris) in the identification of bed bug infestations has become popular during recent years. Their training is usually conducted using live bed bugs, however this thesis describes an alternative method of teaching dogs to find infestations. This alternative method is based on synthetic compounds and dogs trained in this manner have achieved a high positive indication rate.Two species of the tiny, Acacia leaf-eating insect pests in Australia known as thrips, Kladothrips nicolsoni and K. rugosus, have been investigated by means of larval extracts and have been shown to contain large amount of (Z)-3-dodecenoic acid which was synthesised and tested in bioassays.Fruit flies are common pests on fruit in almost every private household. Even though fruit flies has been investigated extensively, their chemical communication has not been completely elucidated. (Z)-4-undecenal was identified as a compound emitted by females, it was synthesised in high stereoisomeric purity and evaluated in biological assays.
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31.
  • Wallin, Erika, 1985-, et al. (author)
  • (Z)-3-Dodecenoic Acid Is the Main Component of Full-Body n-Hexane Extracts from Two Acacia Gall-Inducing Thrips (Thysanoptera) and May Function as an Alarm Pheromone
  • 2014
  • In: Zeitschrift für Naturforschung C - A Journal of Biosciences. - 0939-5075 .- 1865-7125. ; 69C:7-8, s. 335-345
  • Journal article (peer-reviewed)abstract
    • A major interest in the gall-inducing thrips of Australia began with the discovery that some species have eusocial colonies. The origin of social castes remains one of the outstanding questions in evolutionary biology. The inference of the ancestral stage from study of solitary species is important to understanding the evolutionary history of semiochemicals in the social species. Here we investigated two solitary species, Kladothrips nicolsoni and K. rugosus. Whole body extracts revealed that (Z)-3-dodecenoic acid, here reported for the first time in a thrips species, is the main component. (Z)-3-Dodecenoic acid and (E)-3-dodecenoic acid were synthesized in high stereoisomeric purity (> 99.8 %) and exposed to K. nicolsoni 2nd-instar larvae in a contact chemoreception bioassay to test for potential bioactivity. Both isomers decreased the average time spent in the treated area per entry suggesting repellence at the tested dose. (Z)-3-Dodecenoic acid may function as alarm pheromone. (E)-3-Dodecenoic acid increased also the absolute change in direction of larvae compared to an n-hexane control and could potentially function as a repellent.
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32.
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33.
  • Zasadowski, Dariusz, et al. (author)
  • Removal of dissolved and colloidal substances from mechanical pulping white waters by flotation
  • 2011
  • In: 16th International Symposium on Wood, Fiber and Pulping Chemistry - Proceedings, ISWFPC. - Tianjin : China Light Industry Press. ; , s. 1238-1242
  • Conference paper (other academic/artistic)abstract
    • Various sorts of process water, foaming agents and a new chelating surfactant have been investigated in the chemical optimization of flotation ofwaters generated at laboratory and white water from mechanical pulping. Turbidity measurements, the Orcinol method for quantitative carbohydrate analysis and total organic carbon (TOC) as well as gas chromatography (GC) of extractives, have been carried out to determine theremoval and characteristics of Dissolved and Colloidal substances (DisCo). The tests have been realized under different conditions, such as using different flotation cells, foaming agents and complexing agents at different temperatures and pH values. It was found that a reduction of thewhite water turbidity of 70% and a 50% removal of the lipophilic substances from the white water can be obtained in a single-stage flotationunit, and that the selection of suitable flotation equipment, foaming agents and solution conditions plays a very important role in the removalcapacity of the unwished substances.
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34.
  • Zasadowski, Dariusz, et al. (author)
  • Removal of lipophilic extractives and manganese ions from spruce TMP waters in a customized flotation cell
  • 2012
  • In: BioResources. - 1930-2126. ; 7:2, s. 2376-2392
  • Journal article (peer-reviewed)abstract
    • The influence of a chelating surfactant, different foaming agents, cationic polyelectrolytes, pH value, and temperature on the purification efficiency of process waters from a mechanical pulp mill has been studied by flotation in a 1 L customized unit. Turbidity measurements and gas chromatography (GC) were carried out to determine the removal and characteristics of dissolved and colloidal substances (DisCo). The manganese ion content in the process waters before flotation and the metal chelate removal capacity by flotation were determined by Inductively Coupled Plasma (ICP) and Atomic Absorption Spectrometry (AAS) measurements. It was found that a 99% removal of complex bound manganese ions and a 94% decrease in turbidity of the TMP water produced at the laboratory can be achieved in a single-stage flotation with a chelating surfactant and a foaming agent. Furthermore, a 91% decrease in turbidity, the removal of up to 96% of resin and fatty acids, and 93% of triglycerides from TMP water can be obtained after application of a foaming agent.
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35.
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36.
  • Zasadowski, Dariusz, et al. (author)
  • Use of a Voith flotation cell for removal of lipophilic extractives and Mn ions from spruce thermomechanical pulping process waters
  • 2012
  • In: BioResources. - 1930-2126. ; 7:3, s. 2784-2126
  • Journal article (peer-reviewed)abstract
    • The effects of a chelating surfactant and different foaming agents on the efficiency of cleaning process waters from a thermomechanical pulp (TMP) mill were studied in a Voith flotation cell. Turbidity measurements and gas chromatography were used to determine the removal extent and characteristics of dissolved and colloidal substances (DisCo). The metal ion content in the process waters before flotation and the metal chelate removal after flotation were determined using inductively coupled plasma-optical emission spectrometry (ICP-OES). FiberLab (TM) equipment was used to characterize changes in the size of fibers present in the process waters. The results indicate that a decrease in turbidity of up to 91% and the removal of 80% of lipophilic extractives in the TMP water could be obtained using a single-stage flotation unit. Furthermore, the foam fraction was within 5% of the initial volume, and 100% of the Mn2+/chelating surfactant complex added to the TMP water was removed.
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37.
  • Zauli, Agnese, et al. (author)
  • Using odour traps for population monitoring and dispersal analysis of the threatened saproxylic beetles Osmoderma eremita and Elater ferrugineus in central Italy
  • 2014
  • In: Journal of Insect Conservation. - : Springer Science and Business Media LLC. - 1366-638X .- 1572-9753. ; 18:5, s. 801-813
  • Journal article (peer-reviewed)abstract
    • Pheromone-based monitoring could be a very efficient method to assess the conservation status of rare and elusive insect species, but there are still few studies for which pheromone traps have been used to obtain information on presence, abundance, phenology and movements of such insects. We performed a mark-recapture study of two threatened saproxylic beetles, Osmoderma eremita (Scarabaeidae) and its predator Elater ferrugineus (Elateridae), in two beech forests of central Italy using pheromone baited window traps and unbaited pitfall traps. Two lures were used: (1) the male-produced sex pheromone of O. eremita (racemic γ-decalactone) to attract females of both species, and (2) the female-produced sex pheromone of E. ferrugineus (7-methyloctyl (Z)-4-decenoate), to attract conspecific males. In total, 13 O. eremita and 1,247 E. ferrugineus individuals were trapped. For E. ferrugineus, males were detected earlier than females, and 7-methyloctyl (Z)-4-decenoate was much more efficient lure compared to racemic γ-decalactone in detecting its presence. The population size at the two sites were estimated to 520 and 1,369 individuals, respectively. Our model suggests a sampling effort of ten traps checked for 3 days being sufficient to detect the presence of E. ferrugineus at a given site. The distribution of dispersal distances for the predator was best described by the negative exponential function with 1 % of the individuals dispersing farther than 1,600 m from their natal site. In contrast to studies on these beetles in Northern Europe, the activity pattern of the two beetle species was not influenced by variation in temperature during the season.
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