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  • 51. El-Seedi, Hesham R.
    et al.
    Khalil, Nasr S.
    Azeem, Muhammad
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Taher, Eman A.
    Goransson, Ulf
    Pålsson, Katinka
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Chemical Composition and Repellency of Essential Oils From Four Medicinal Plants Against Ixodes ricinus Nymphs: (Acari Ixodidae)2012Inngår i: Journal of medical entomology, ISSN 0022-2585, E-ISSN 1938-2928, Vol. 49, nr 5, s. 1067-1075Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In our search for effective tick repellents from plant origin, we investigated the effect of essential oils of four medicinal and culinary plants belonging to the family Lamiaceae on nymphs of the tick Ixodes ricinus (L.). The essential oils of the dry leaves of Rosmarinus officinalis (Rosemary) (L.), Mentha spicata (Spearmint) (L.), Origanum majorana (Majoram) (L.), and Ocimum basilicum (Basil) (L.) were isolated by steam distillation and 15 mu g/cm(2) concentration of oils was tested against ticks in a laboratory bioassay. The oils of R. officinalis, M. spicata, and O. majorana showed strong repellency against the ticks 100, 93.2, and 84.3%, respectively, whereas O. basilicum only showed 64.5% repellency. When tested in the field, the oils of R. officinalis and M. spicata showed 68.3 and 59.4% repellency at a concentration of 6.5 mu g/cm(2) on the test cloths. The oils were analyzed by gas chromatography mass spectrometry and the major compounds from the most repellent oils were 1,8-cineole, camphor, linalool, 4-terpineol, borneol, and carvone.

  • 52.
    Eneh, Lynda
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Borg Karlsson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Fillinger, Ulrike
    Rajarao, Gunaratna
    KTH, Skolan för bioteknologi (BIO), Industriell bioteknologi.
    Lindh, Jenny
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Factors associated with preferred Anopheles gambiae s.l. oviposition sitesManuskript (preprint) (Annet vitenskapelig)
  • 53.
    Eneh, Lynda
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Fillinger, U.
    Human Hlth Theme, Int Ctr Insect Physiol & Ecol, Thomas Odhiambo Campus, Mbita, Kenya..
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Rajarao, Gunaratna Kuttuva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Lindh, Jenny
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Anopheles arabiensis oviposition site selection in response to habitat persistence and associated physicochemical parameters, bacteria and volatile profiles2019Inngår i: Medical and Veterinary Entomology, ISSN 0269-283X, E-ISSN 1365-2915, Vol. 33, nr 1, s. 56-67Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A better understanding of the oviposition behaviour of malaria vectors might facilitate the development of new vector control tools. However, the factors that guide the aquatic habitat selection of gravid females are poorly understood. The present study explored the relative attractiveness of similar artificial ponds (0.8 m(2)) aged at varying lengths prior to opening in such a way that wild Anopheles arabiensis could choose between ponds that were freshly set up, or were aged 4 or 17 days old, to lay eggs. Physicochemical parameters, bacterial profile and volatile organic compounds emitted from ponds were investigated over three experimental rounds. Fresh ponds contained on average twice as many An. arabiensis instar larvae (mean 50, 95% confidence interval (CI) = 29-85) as the ponds that had aged 4 days (mean = 24, 95% CI = 14-42) and 17 days (mean = 20, 95% CI: 12-34). Fresh ponds were associated with a significantly higher turbidity combined with higher water temperature, higher nitrite levels and a lower pH and chlorophyll level than the older ponds. Round by round analyses suggested that bacteria communities differed between age groups and also that 4-heptanone, 2-ethylhexanal and an isomer of octenal were exclusively detected from the fresh ponds. These characteristics may be useful with respect to developing attract and kill strategies for malaria vector control.

  • 54.
    Eneh, Lynda
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Fillinger, Ulrike
    Rajarao, Gunaratna
    KTH, Skolan för bioteknologi (BIO), Industriell bioteknologi.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Lindh, Jenny
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Oviposition choice of malaria mosquitoes Anopheles gambiae s.l.:  do they choose between similar habitats?Manuskript (preprint) (Annet vitenskapelig)
  • 55.
    Eneh, Lynda K.
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Okal, Michael N.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Fillinger, Ulrike
    Lindh, Jenny M.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Gravid Anopheles gambiae sensu stricto avoid ovipositing in Bermuda grass hay infusion and it's volatiles in two choice egg-count bioassays2016Inngår i: Malaria Journal, ISSN 1475-2875, E-ISSN 1475-2875, Vol. 15, artikkel-id 276Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: A number of mosquito species in the Culex and Aedes genera prefer to lay eggs in Bermuda grass (Cynodon dactylon) hay infusions compared to water alone. These mosquitoes are attracted to volatile compounds from the hay infusions making the infusions effective baits in gravid traps used for monitoring vectors of arboviral and filarial pathogens. Since Bermuda grass is abundant and widespread, it is plausible to explore infusions made from it as a potential low cost bait for outdoor monitoring of the elusive malaria vector Anopheles gambiae s.s. Methods: This study investigated preferential egg laying of individual An. gambiae s.s. in hay infusion or in tap water treated with volatiles detected in hay infusion headspace compared to tap water alone, using two-choice egg-count bioassays. Infusions were prepared by mixing 90 g of dried Bermuda grass (hay) with 24 L of unchlorinated tap water in a bucket, and leaving it for 3 days at ambient temperature and humidity. The volatiles in the headspace of the hay infusion were sampled with Tenax TA traps for 20 h and analysed using gas chromatography coupled to mass spectrometry. Results: In total, 18 volatiles were detected in the infusion headspace. Nine of the detected compounds and nonanal were selected for bioassays. Eight of the selected compounds have previously been suggested to attract/stimulate egg laying in An. gambiae s.s. Gravid females were significantly (p < 0.05) less likely to lay eggs in hay infusion dilutions of 25, 50 and 100 % and in tap water containing any of six compounds (3-methylbutanol, phenol, 4-methylphenol, nonanal, indole, and 3-methylindole) compared to tap water alone. The oviposition response to 10 % hay infusion or any one of the remaining four volatiles (4-hepten-1-ol, phenylmethanol, 2-phenylethanol, or 4-ethylphenol) did not differ from that in tap water. Conclusions: Anopheles gambiae s.s. prefers to lay eggs in tap water rather than Bermuda grass hay infusion. This avoidance of the hay infusion appears to be mediated by volatile organic compounds from the infusion. It is, therefore, unlikely that Bermuda grass hay infusion as formulated and used in gravid traps for Culex and Aedes mosquitoes will be suitable baits for monitoring gravid An. gambiae s.s.

  • 56.
    Eneh, Lynda K.
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Saijo, Hiromi
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Lindh, Jenny M.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Rajarao, Gunaratna Kuttuva
    KTH, Skolan för bioteknologi (BIO), Industriell bioteknologi.
    Cedrol, a malaria mosquito oviposition attractant is produced by fungi isolated from rhizomes of the grass Cyperus rotundus2016Inngår i: Malaria Journal, ISSN 1475-2875, E-ISSN 1475-2875, Vol. 15, artikkel-id 478Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Cedrol, a sesquiterpene alcohol, is the first identified oviposition attractant for African malaria vectors. Finding the natural source of this compound might help to elucidate why Anopheles gambiae and Anopheles arabiensis prefer to lay eggs in habitats containing it. Previous studies suggest that cedrol may be a fungal metabolite and the essential oil of grass rhizomes have been described to contain a high amount of different sesquiterpenes. Results: Rhizomes of the grass Cyperus rotundus were collected in a natural malaria mosquito breeding site. Two fungi were isolated from an aqueous infusion with these rhizomes. They were identified as Fusarium falciforme and a species in the Fusarium fujikuroi species complex. Volatile compounds were collected from the headspace above fungal cultures on Tenax traps which were analysed by gas chromatography-mass spectrometry (GCMS). Cedrol and a cedrol isomer were detected in the headspace above the F. fujikuroi culture, while only cedrol was detected above the F. falciforme culture. Conclusion: Cedrol an oviposition attractant for African malaria vectors is produced by two fungi species isolated from grass rhizomes collected from a natural mosquito breeding site.

  • 57.
    Eneh, Lynda
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Okal, Mike
    Borg-Karlson, Anna-Karin
    Fillinger, Ulrike
    Lindh, Jenny
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Hay infusion and its volatiles are avoided for egg-laying by the malaria mosquito Anopheles gambiae s.sManuskript (preprint) (Annet vitenskapelig)
  • 58.
    Eneh, Lynda
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Saijo, Hiromi
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Lindh, Jenny
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Rajarao, Gunaratna
    KTH, Skolan för bioteknologi (BIO), Industriell bioteknologi.
    Cedrol, a malaria mosquito oviposition attractant is produced by fungi isolated from rhizomes of the grass Cyperus rotundusManuskript (preprint) (Annet vitenskapelig)
  • 59. Eriksson, M.
    et al.
    Dalhammar, Gunnel
    KTH, Tidigare Institutioner                               , Bioteknologi.
    Borg-Karlson, Anna-Karin
    KTH, Tidigare Institutioner                               , Kemi.
    Biological degradation of selected hydrocarbons in an old PAH/creosote contaminated soil from a gas work site2000Inngår i: Applied Microbiology and Biotechnology, ISSN 0175-7598, E-ISSN 1432-0614, Vol. 53, nr 5, s. 619-626Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An old PAH/creosote contaminated soil (total similar to 300 mu g PAH/g soil) from a former gas work site in Stockholm, Sweden, has been treated at 20 degrees C with the addition of various nutrients and inoculated with bacteria (isolated from the soil) to enhance the degradation of selected hydrocarbons. Microcosm studies showed that the soil consisted of two contaminant fractions: one available, easily degraded fraction and a strongly sorbed, recalcitrant one. The bioavailable fraction, monitored by headspace solid phase microextraction, contained aromatics with up to three rings, and these were degraded within 20 days down to non-detectable levels (ng PAH/g soil) by both the indigenous bacteria and the externally inoculated samples. The nutrient additives were: a minimal medium (Bushnell-Haas), nitrate, nitrite, potting soil (Anglamark, Sweden), sterile water and aeration with Bushnell-Haas medium. After 30 days treatment most of the sorbed fractions were still present in the soil. Stirring or mechanical mixing of the soil slurries had the greatest effect on degradation, indicating that the substances were too strongly sorbed for the microorganisms. When stirring the choice of nutrient seemed less important. For the non-stirred samples the addition of nitrate with the bacterial inoculum showed the best degradation, compared to the other non-stirred samples. At the end of the experiments, accumulations of metabolites/degradation products, such as 9H-fluorenone, 4-hydroxy-9H-fluorenone, 9,10-phenanthrenedione and 4H-cyclopenta[def]phenanthrenedione were detected. The metabolite 4-hydroxy-9H-fluorenone increased by several orders of magnitude during the biological treatments. Microbial activity in the soil was measured by oxygen consumption and carbon dioxide production.

  • 60. Eriksson, M.
    et al.
    Faldt, J.
    Dalhammar, Gunnel
    KTH, Tidigare Institutioner                               , Bioteknologi.
    Borg-Karlson, Anna-Karin
    KTH, Tidigare Institutioner                               , Kemi.
    Determination of hydrocarbons in old creosote contaminated soil using headspace solid phase microextraction and GC-MS2001Inngår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 44, nr 7, s. 1641-1648Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Headspace solid phase microextraction (HS-SPME) has been used together with GC-MS to analyze organic substances directly in a soil, heavily contaminated with PAHs/creosote (similar to 300 mg/kg soil), from an old gaswork site in Stockholm, Sweden. The HS-SPME results, both qualitative and quantitative, were compared with traditional liquid extraction using ethyl acetate/hexane (20:80). It was shown that the concentrations determined with HS-SPME at 60 degreesC correlated well, for compounds containing up to two and three aromatic rings (naphthalenes, acenaphthene, acenaphthylene and fluorenes, while a lower concentration was obtained for phenanthrene, anthracene, fluoranthene and pyrene. The total concentrations for each compound determined with HS-SPME ranged from 2 to 25 mug/g soil. Quantification was done using standard addition of compounds directly to the soil samples. The bioavailable fraction of the compounds in the contaminated soil at 20 degreesC was analyzed using external calibration by spiking sterile uncontaminated sand (same texture and particle size as the contaminated soil but without a heavily sorbed organic fraction) with hydrocarbon standards in different concentrations. Storage of exposed fibers at 20 degreesC showed that analysis should be done within two days to make qualitative measurements and earlier (as soon as possible) for quantitative determinations.

  • 61. Faldt, J.
    et al.
    Eriksson, M.
    Valterova, I.
    Borg-Karlson, Anna-Karin
    KTH, Tidigare Institutioner                               , Kemi.
    Comparison of headspace techniques for sampling volatile natural products in a dynamic system2000Inngår i: Zeitschrift für Naturforschung C - A Journal of Biosciences, ISSN 0939-5075, E-ISSN 1865-7125, Vol. 55, nr 04-mar, s. 180-188Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Commonly used dynamic sorption techniques for collecting biologically active volatile compounds have been compared. Solid phase microextraction (SPME) using two types of fibers (polydimethylsiloxane, PDMS, 100 mu m, and carbowax/divinylbenzene, CW/DVB, 65 mu m) was compared to purge and trap methods (Porapak Q, Tenax TA and charcoal) and a technique based on absorption in methanol in a cooling bath. Sampling was done in a stream of purified air (20 ml/min) in a closed and temperature-regulated (27 degrees C) glass tube, passing over a capillary tube containing a hexane solution of tridecane, heptadecane, 1-octen-3-ol, 1-hexadecanol, ethyl tetradecanoate, alpha-pinene, linalool, terpinen-4-ol, cis-verbenol, verbenone, beta-caryophyllene, E,E-farnesol, and geranylgeraniol. With all of the methods, the sampling was performed for a period of 30 min before extraction and analysis was done on a GC-FID system. In general, SPME gave a higher response for all compounds except for alpha-pinene, which was only extracted by the CW/DVB fiber. Purge and trap methods and methanol absorption gave the same response for all substances extracted. None of the methods extracted hexadecanol and geranylgeraniol under the conditions used. However, the SPME equipped with the PDMS coating extracted heptadecane, E,E-farnesol and ethyl tetradecanoate. Our results show that SPME, when selecting the fibers to fit the polarity and volatility of the compounds, is an outstanding extraction method compared to purge and trap and methanol absorption, especially for a qualitative analysis. The best conditions for storing fibers exposed to compounds of high volatility were at low temperatures (6 degrees C) in sealed vials, while the worst way was to leave the exposed fiber unprotected at room temperature (22 degrees C). The dynamic sampling system was effectively tested on a fruiting body of a polypore fungus (Ganoderma applanatum) emitting 1-octen-3-ol, and again SPME showed to be the most sensitive technique.

  • 62. Faldt, J.
    et al.
    Sjodin, K.
    Persson, M.
    Valterova, I.
    Borg-Karlson, Anna-Karin
    KTH, Tidigare Institutioner                               , Kemi.
    Correlations between selected monoterpene hydrocarbons in the xylem of six Pinus (pinaceae) species2001Inngår i: Chemoecology, ISSN 0937-7409, E-ISSN 1423-0445, Vol. 11, nr 2, s. 97-106Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The compositions of 23 monoterpene hydrocarbons of six pine species (Pinus sylvestris, P. yunnanensis ll,ris, P. armandii, P. tropicalis, P. cubensis and P. caribaca) were compared, using multivariate data analysis. Four of the six species were clearly different from the other species in a Principal Components Analysis (PCA) model, based on the relative amounts (selective normalization) of the monoterpenes. The correlation coefficients between constituents were determined separately for each species and the strongest correlations were found between (+)-alpha -pinene and (+)-camphene and between the corresponding (-)-enantiomers, in all species. This pattern, i.e. a good correlation in all species, was neither shown by the correlation of the structurally more similar (+)-alpha/beta -pinenes, nor by the (-)-alpha/beta -pinenes or within the enantiomeric pairs of alpha -pinene and beta -pinene. For these pairs of monoterpenes, good correlations were found in some species. None of the species showed good correlations in all the investigated monoterpene pairs presented here. Correlations between monoterpenes in insect-attacked trees (P. cubensis and P. caribaea, attacked by Dioryctria horneana, and P. yunnanensis, attacked by Tomicus piniperda) were also determined. The results are discussed from chemotaxonomic and biosynthetic points of view.

  • 63. Faldt, Jenny
    et al.
    Solheim, Halvor
    Langstrom, Bo
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Influence of fungal infection and wounding on contents and enantiomeric compositions of monoterpenes in phloem of Pinus sylvestris2006Inngår i: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 32, nr 8, s. 1779-1795Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To identify chemical resistant markers induced by fungal or mechanical injury, young trees of Scots pine (Pinus sylvestris) were subjected to inoculations of blue stain fungi associated with the pine shoot beetles Tomicus piniperda and T. minor. Among the 20 trees selected for chemical analyses, 16 were divided into four groups: one as control and three were pretreated by wounding only, or by inoculation with either the blue stain fungus Leptographium wingfieldii or Ophiostoma canum. Four wk after pretreatment, all 16 pretreated trees were mass-inoculated with L. wingfieldii. The absolute and relative amounts, as well as the enantiomeric compositions of monoterpene hydrocarbons in the phloem, were determined via a small sample of the phloem before and after the pretreatment and mass inoculation, by using two-dimensional gas chromatography (2D GC) and GC-mass spectrometry (MS). After mass inoculation, the absolute amounts of most of the monoterpenes decreased in the phloem sampled > 20 cm from the fungal infection, and were higher in the phloem sampled within the infected reaction zone. The relative amounts of both (-)-beta-pinene and (-)-limonene increased in phloem samples taken > 20 cm above the fungal inoculation in the preinoculated trees compared with phloem sampled from the remaining four control trees. The enantiomeric compositions of beta-pinene and limonene changed, after fungal growth, at defined distances from the inoculation site: the proportion of the (-)-enantiomers was highest in the phloem sampled > 20 cm from the fungal inoculation. Four wk after pretreatment, monoterpene production in the phloem at the site of inoculation was more enhanced by L. wingfieldii than by O. canum. However, the different virulence levels of the fungi did not affect the enantiomeric composition of the monoterpenes. The biosynthesis of monoterpene enantiomers is discussed in relation to induced pathogen resistance.

  • 64. Fors, Lisa
    et al.
    Liblikas, Ilme
    Andersson, Petter
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Cabezas, Nancy
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Mozuraitis, Raimondas
    Hamback, Peter A.
    Chemical communication and host search in Galerucella leaf beetles2015Inngår i: Chemoecology, ISSN 0937-7409, E-ISSN 1423-0445, Vol. 25, nr 1, s. 33-45Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    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.

  • 65. Fountain, M. T.
    et al.
    Baroffio, C.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Brain, P.
    Cross, J. V.
    Farman, D. I.
    Hall, D. R.
    Ralle, B.
    Rendina, P.
    Richoz, P.
    Sigsgaard, L.
    Storberget, S.
    Trandem, N.
    Wibe, A.
    Design and deployment of semiochemical traps for capturing Anthonomus rubi Herbst (Coleoptera: Curculionidae) and Lygus rugulipennis Poppius (Hetereoptera: Miridae) in soft fruit crops2017Inngår i: Crop Protection, ISSN 0261-2194, E-ISSN 1873-6904, Vol. 99, s. 1-9Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Strawberry blossom weevil (SBW), Anthonomus rubi Herbst (Coleoptera: Curculionidae) and European tarnished plant bug (ETB), Lygus rugulipennis Poppius (Hetereoptera: Miridae), cause significant damage to strawberry and raspberry crops. Using the SBW aggregation pheromone and ETB sex pheromone we optimized and tested a single trap for both species. A series of field experiments in crops and semi-natural habitats in five European countries tested capture of the target pests and the ability to avoid captures of beneficial arthropods. A Unitrap containing a trapping agent of water and detergent and with a cross vane was more efficient at capturing both species compared to traps which incorporated glue as a trapping agent. Adding a green cross vane deterred attraction of non-pest species such as bees, but did not compromise catches of the target pests. The trap caught higher numbers of ETB and SBW if deployed at ground level and although a cross vane was not important for catches of ETB it was needed for significant captures of SBW. The potential for mass trapping SBW and ETB simultaneously in soft fruit crops is discussed including potential improvements to make this more effective and economic to deploy.

  • 66. Francke, W.
    et al.
    Karalius, V.
    Plass, E.
    Lehmann, L.
    Dos Santos, A.
    Buda, V.
    Borg-Karlson, Anna-Karin
    KTH, Tidigare Institutioner, Kemi.
    Mozuraitis, Raimondas
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    New type of sesiidae sex pheromone identified from the hornet moth Sesia apiformis2004Inngår i: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 30, nr 4, s. 805-817Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Two components of the female-produced sex pheromone of the hornet moth, Sesia apiformis, were identified as (3Z, 13Z)-octadeca-3,13-dien-1-ol (3Z, 13Z-18:OH) and (2E, 13Z)-octadeca-2,13-dienal (2E, 13Z-18:Al), a pheromone structure new in Sesiidae. Pooled gland extracts showed the two major compounds in a proportion of ca. 2:3, while SPME-investigations on single calling females revealed a ratio of ca. 1:7. Although the single compounds were not attractive, a 2: 3 mixture proved to be highly active towards males in field tests. Small amounts of (2E, 13Z)-octadecadienol (2E, 13Z-18:OH) were found in the sex pheromone gland of females, however, the biological significance of the compound remains unclear. Methyl sulfide was found to readily react with 2-alkenals, providing an effective new method for the characterization of this type of compound upon GC/MS. The derivatives, 1,1,3-tris(methylthio)alkanes, are the products of the addition of methyl sulfide to the double bond and the transformation of the carbonyl group into the corresponding bis(methylthio)acetal. The mass spectra of these compounds are characterized by diagnostic signals at m/z 107 and/or m/z 121. These fragments represent the first carbon unit or the first two carbon units of the derivative, respectively. The parent signal in the spectra of thiomethyl derivatives of 2-alkenals showing no other double bonds is represented by m/z M+-121, formed upon loss of the first two carbon units. By employing a solution of methyl sulfide in dimethyl sulfide, the double bond positions in 2E, 13Z-18:Al could be fully characterized by GC/MS.

  • 67. Friberg, Magne
    et al.
    Vongvanich, Namphung
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Kemp, Darrell J.
    Merilaita, Sami
    Wiklund, Christer
    Female mate choice determines reproductive isolation between sympatric butterflies2008Inngår i: Behavioral Ecology and Sociobiology, ISSN 0340-5443, E-ISSN 1432-0762, Vol. 62, nr 6, s. 873-886Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Animal courtship rituals are important for species recognition, and a variety of cues might be utilized to recognize conspecific mates. In this paper, we investigate different species-recognition mechanisms between two sympatric butterfly sister species: the wood white (Leptidea sinapis) and Real's wood white (Leptidea reali). We show that males of both species frequently court heterospecific females both under laboratory and field conditions. The long-lasting elaborate courtships impose energetic costs, since the second courtship of males that were introduced to two subsequent conspecific females lasted on average only one fourth as long as the first courtship. In this paper, we demonstrate that premating reproductive isolation is dependent on female unwillingness to accept heterospecific mates. We studied female and male courtship behavior, chemical signaling, and the morphology of the sexually dimorphic antennae, one of the few male traits visible for females during courtship. We found no differences in ultraviolet (UV) reflectance and only small differences in longer wavelengths and brightness, significant between-species differences, but strongly overlapping distributions of male L. sinapis and L. reali antennal morphology and chemical signals and minor differences in courtship behavior. The lack of clear-cut between-species differences further explains the lack of male species recognition, and the overall similarity might have caused the long-lasting elaborate courtships, if females need prolonged male courtships to distinguish between con- and heterospecific suitors.

  • 68. Galizia, C. G.
    et al.
    Kunze, J.
    Gumbert, A.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Sachse, S.
    Markl, C.
    Menzel, R.
    Relationship of visual and olfactory signal parameters in a food-deceptive flower mimicry system2005Inngår i: Behavioral Ecology, ISSN 1045-2249, E-ISSN 1465-7279, Vol. 16, nr 1, s. 159-168Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Pollinators such as bees are attracted to flowers by their visual display and their scent. Although most flowers reinforce visits by providing pollen and/or nectar, there are species-notably from the orchid family-that do not but do resemble rewarding species. These mimicry relationships provide ideal opportunities for investigating the evolution of floral signals and their impact on pollinator behavior. Here, we have reanalyzed a case of specialized food mimicry between the orchid Orchis israelitica and its model, the lily Bellevalia flexuosa. Based on current knowledge of insect sensory physiology, we were able to characterize both the visual and olfactory signals of model and mimic, as well as of two phylogenetically related orchids. By using a color vision model, we mapped each species' visual signals to the perceptual space of honeybees and found an apparent shift of the mimic's visual signals towards the model. We confirm that visual mimicry is present. We analyzed the flower odors by using gas chromatography/mass spectroscopy. We related these signals to the perceptual space of the pollinators by testing the scent extracts physiologically, using in vivo brain imaging. We found no evidence of olfactory mimicry. The results indicate that evolutionary pressure acts on the visual, but not olfactory, traits of O. israelitica toward a higher similarity to its model. Apparently, odor mismatch does not prevent a bee from landing on a flower that has the expected visual display. The results therefore argue for the dominance of visual stimuli in short-distance flower choice. The orchid may still depend on long-distance olfactory attraction originating from neighboring model plants.

  • 69. Garboui, S. S.
    et al.
    Borg-Karlson, Anna-Karin
    Pålsson, Katinka
    Tick Repellent Properties of Three Libyan Plants2009Inngår i: Journal of medical entomology, ISSN 0022-2585, E-ISSN 1938-2928, Vol. 46, nr 6, s. 1415-1419Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Specimens of Salvadora persica Wallich (Salvadoraceae), Pistacia atlantica Desfontaines (Anacardiaceae), and Juniperus phoenicea L. (Cupressaceae) were collected at The Green Mountain in northeastern Libya. The tick-repellent effects of the essential oils from the plants were evaluated using host-seeking nymphs of Ixodes ricinus L. (Acari: Ixodidae) in the laboratory. Significant tick repellent effects were observed for the oils of all three species, but the duration of action was short. The oils were obtained by steam distillation. Volatile compounds of the essential oils were collected by solid phase microextraction and the constituents were identified by gas chromatography-mass spectrometry.

  • 70. Garboui, Samira S.
    et al.
    Jaenson, Thomas G. T.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Palsson, Katinka
    Repellency of methyl jasmonate to Ixodes ricinus nymphs (Acari: Ixodidae)2007Inngår i: Experimental & applied acarology, ISSN 0168-8162, E-ISSN 1572-9702, Vol. 42, nr 3, s. 209-215Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In our search for tick repellents of plant origin, to be used as alternatives to commercial arthropod repellents, we investigated the effect of the well known plant signaling compound methyl jasmonate (MJ) using nymphs of the tick Ixodes ricinus. In laboratory tests, pieces of cloth with MJ at 0.075, 0.15, 0.30 and 0.75 mg/cm(2) yielded increasing repellencies against the nymphs: 57%, 71%, 92% and 99%, respectively, of the nymphs did not cling to the cloth. Repellency of MJ was also investigated in a tick-infested woodland area in central Sweden. Cotton flannel cloths sprayed with 0.05, 0.1 or 0.2 mg/cm(2) MJ dissolved in acetone were dragged over the ground vegetation. The numbers of nymphs on the treated cloths were significantly lower than those on the untreated cloth. Thus, MJ has, at the concentrations tested, significant repellent activity against I. ricinus nymphs.

  • 71. Gonzalez, N. J. D.
    et al.
    Borg Karlsson, Anna Karin
    Artaxo, P.
    Guenther, A.
    Krejci, R.
    Noziere, B.
    Noone, K.
    Primary and secondary organics in the tropical Amazonian rainforest aerosols: chiral analysis of 2-methyltetraols2014Inngår i: ENVIRON SCI-PROC IMP, ISSN 2050-7887, Vol. 16, nr 6, s. 1413-1421Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This work presents the application of a new method to facilitate the distinction between biologically produced (primary) and atmospherically produced (secondary) organic compounds in ambient aerosols based on their chirality. The compounds chosen for this analysis were the stereomers of 2-methyltetraols, (2R, 3S)- and (2S, 3R)-methylerythritol, (L- and D-form, respectively), and (2S, 3S)- and (2R, 3R)-methylthreitol (L- and D-form), shown previously to display some enantiomeric excesses in atmospheric aerosols, thus to have at least a partial biological origin. In this work PM10 aerosol fractions were collected in a remote tropical rainforest environment near Manaus, Brazil, between June 2008 and June 2009 and analysed. Both 2-methylerythritol and 2-methylthreitol displayed a net excess of one enantiomer (either the L- or the D-form) in 60 to 72% of these samples. These net enantiomeric excesses corresponded to compounds entirely biological but accounted for only about 5% of the total 2-methyltetrol mass in all the samples. Further analysis showed that, in addition, a large mass of the racemic fractions (equal mixtures of D- and L-forms) was also biological. Estimating the contribution of secondary reactions from the isomeric ratios measured in the samples (=ratios 2-methylthreitol over 2-methylerythritol), the mass fraction of secondary methyltetrols in these samples was estimated to a maximum of 31% and their primary fraction to a minimum of 69%. Such large primary fractions could have been expected in PM10 aerosols, largely influenced by biological emissions, and would now need to be investigated in finer aerosols. This work demonstrates the effectiveness of chiral and isomeric analyses as the first direct tool to assess the primary and secondary fractions of organic aerosols.

  • 72. Gonzalez, Nelida J. D.
    et al.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Pettersson Redeby, Johan
    KTH, Skolan för kemivetenskap (CHE), Kemi, Analytisk kemi.
    Noziere, Barbara
    Krejci, Radovan
    Pei, Yuxin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Dommen, Josef
    Prevot, Andre S. H.
    New method for resolving the enantiomeric composition of 2-methyltetrols in atmospheric organic aerosols2011Inngår i: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1218, nr 51, s. 9288-9294Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In order to facilitate the determination of the primary and secondary origin of atmospheric organic aerosols, a novel method involving chiral capillary gas chromatography coupled with mass spectrometry has been developed and validated. The method was focused on the analysis of 2-methylerythritol and 2-methylthreitol, considered to be tracers of secondary organic aerosols from the oxidation of atmospheric isoprene. The method was validated by performing various tests using authentic standards, including pure enantiomeric standards. The result showed that the analytical method itself does not affect the enantiomeric composition of the samples analyzed. The method was applied on atmospheric aerosols from a boreal forest collected in Aspvreten, Sweden and on laboratory samples obtained from liquid phase oxidation of isoprene and smog chamber experiments. Aerosol samples contained one enantiomer of 2-methylerythritol in significantly larger quantities than the others. In contrast, the liquid-phase oxidation of isoprene and its gas-phase oxidation in the smog chamber produced all enantiomers in equal quantities. The results obtained where the enantiomer fraction, EF, is larger than 0.50 suggest that 2-methyltetrols in atmospheric aerosols may also have biological origin. Information about the differences between enantiomer fractions obtained using this method brings new insights in the area of atmospheric aerosols.

  • 73. Jaenson, T. G. T.
    et al.
    Palsson, K.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Evaluation of extracts and oils of mosquito (Diptera: Culicidae) repellent plants from Sweden and Guinea-Bissau2006Inngår i: Journal of medical entomology, ISSN 0022-2585, E-ISSN 1938-2928, Vol. 43, nr 1, s. 113-119Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In laboratory tests, ethyl acetate extracts of Hyptis, suaveolens Poit. from Guinea-Bissau and Rhododendon tomentosum (Stokes) H. Harmaja (formerly Ledum palustre L.) and Myrica gale L. significantly reduced probing activity of Aedes aegypti (L.). In the field in southern Sweden, extracts of leaves of R. tomentosum, M. gale, and Achillea millefolium L. significantly reduced biting by Aedes mosquitoes. Volatile compounds from M. gale, R. tomentosum, A. millefolium, and H. suaveolens were collected by solid phase microextraction (SPME). Alternatively, compounds in the plants were subjected to extraction by organic solvents of different polarities or by steam distillation and collection by SPME. Compounds collected were identified by gas chromatography-mass spectrometry. Leaves of H. suaveolens contained mainly beta-caryophyllene, bergamotene, and terpinolene. The volatile fraction of an ethyl acetate extract of H. suaveolens was collected by SPME and included beta-caryophyllene, (-) -sabinene, beta-pinene, limonene, alpha-pinene, and bergamotene. The main volatiles detected were alpha-pinene, alpha-phellandrene, myrcene, and limonene from M. gale leaves or inflorescences; pcymene, sabinene, and terpinyl acetate from leaves of R. tornentoston; and (-)-germacrene D, beta-pinene, sabinene, and alpha-pinene from A. millefolium leaves or inflorescences. The selected plant species contained numerous volatiles known to have insecticidal, acaricidal, pesticidal, and/orinsect repellent properties.

  • 74. Jaenson, T. G. T.
    et al.
    Palsson, K.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Evaluation of extracts and oils of tick-repellent plants from Sweden2005Inngår i: Medical and Veterinary Entomology, ISSN 0269-283X, E-ISSN 1365-2915, Vol. 19, nr 4, s. 345-352Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Leaves of Myrica gale Linnaeus (Myricaceae), Rhododendron tomentosum (Stokes) H. Harmaja (formerly Ledum palustre Linnaeus: Ericaceae) and Artemisia absinthium Linnaeus (Asteraceae) were extracted with organic solvents of different polarities and the essential oils of leaves were obtained by steam distillation. The extracts or oils were tested in the laboratory for repellency against host-seeking nymphs of Ixodes ricinus Linnaeus (Acari: Ixodidae). Rhododendron tomentosum oil, 10%, diluted in acetone, exhibited 95% repellency; R. tomentosum and A. absinthium extracts in ethyl acetate, > 70% repellency; A. absinthium extract in hexane, similar to 62% repellency; and M. gale oil, 10%, similar to 50% repellency on I. ricinus nymphs. Compounds in the leaf extracts or in the oils were collected by solid phase microextraction (SPME) and identified by gas chromatography-mass spectrometry (GC-MS) and/or MS. Characteristic volatiles detected from oil or extract of M. gale were the monoterpenes 1,8-cineole, alpha-terpineol, 4-terpineol and thujenol; and of R. tomentosum myrcene and palustrol. Characteristic volatiles from leaf extracts of A. absinthium were sabinene, oxygenated monoterpenes, e.g. thujenol and linalool, and geranyl acetate. Each plant species synthesized numerous volatiles known to exhibit acaricidal, insecticidal, 'pesticidal' and/or arthropod repellent properties. These plants may be useful sources of chemicals for the control of arthropods of medical, veterinary or agricultural importance.

  • 75. Karalius, V.
    et al.
    Mozuraitis, R.
    Buda, V.
    Libikas, I.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Sex attractants for six moth species of the families Brachodidae, Choreutidae and Tineidae from Kazakhstan and Lithuania2005Inngår i: Zeitschrift für Naturforschung C - A Journal of Biosciences, ISSN 0939-5075, E-ISSN 1865-7125, Vol. 60, nr 08-jul, s. 625-631Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Sex attractants were established for one Brachodidae, three Choreutidae and two Tineidae moth species during field screening tests with (2E,13Z)-octadecadien-1-al, (2E,13Z)-, (3E,13Z)-, (3Z,13Z)-octadecadien-1-ols and their acetates (2E,13Z-18:Ald, 2E,13Z-, 3E,13Z-, 3Z,13Z-18:OH/OAc) as well as of binary mixtures of these compounds in West-Kazakhstan and Lithuania. Males of Brachodes appendiculata were attracted by 3E,13Z-18:OAc, Prochoreutis ultimana and P myllerana by 2E,13Z-18:OH, Monopis palidella by 2E,13Z-18:Ald and Triaxomera fulvimitrella by binary mixtures of 3Z,13Z-18:OAc with either 3E,13Z-18:OH in the ratio of 5:5 or 3Z,13Z-18:OH in the ratio of 9:1 (v/v). The 3-component mixture composed of 2E,13Z-18:OH, 3Z,13Z-18:OH and 2E,13Z-18:Ald in the ratio 1:1:1 was developed to attract Prochoreutis sehestediana males. Attraction antagonists for B. appendiculata, P ultimana and M. palidella were shown.

  • 76.
    Kusumoto, Norihisa
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi. Akita Prefectural University, Japan.
    Zhao, Tao
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Swedjemark, G.
    Ashitani, T.
    Takahashi, K.
    Borg-Karlson, Anna Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Antifungal properties of terpenoids in Picea abies against Heterobasidion parviporum2014Inngår i: Forest Pathology, ISSN 1437-4781, E-ISSN 1439-0329, Vol. 44, nr 5, s. 353-361Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The antifungal properties of 14 major oleoresin-constitutive terpenoids of Norway spruce (Picea abies) against Heterobasidion parviporum were evaluated in vitro at three gradient concentrations, 0.1, 0.2 and 0.4 mu mol/cm(2), on potato dextrose agar medium. Eight monoterpene hydrocarbons (+)- and (-)-alpha-pinene, (-)-beta-pinene, (+)-3-carene, myrcene, (+)- and (-)-limonene, terpinolene; four oxygenated monoterpenes alpha-terpineol, terpinen-4-ol, 1,8-cineole, bornyl acetate; and two resin acids abietic acid and dehydroabietic acid were selected. Abietic and dehydroabietic acids showed the highest antifungal activities at all concentrations. Among oxygenated monoterpenes, bornyl acetate and alpha-terpineol showed antifungal activity at the highest concentration. Among monoterpene hydrocarbons, (+)-alpha-pinene showed similar activity to terpinen-4-ol and 1,8-cineole at the highest concentration; however, it was lower than alpha-terpineol and bornyl acetate. Other monoterpene hydrocarbons inhibited mycelial growth by <10%. Re-extraction of medium surfaces after the test period revealed that most alpha-terpineol and terpinen-4-ol remained unchanged on the surface but monoterpene hydrocarbons completely disappeared. However, notable fungal transformed products were observed on surfaces applied with 1,8-cineole and bornyl acetate. Thus, mycelial growth inhibition of monoterpenoids might be caused by complex functions such as biodegradation and/or detoxification by interaction between mycelium and compound. These results provide a basis for future studies considering the role of chemodiversity in the comprehensive chemical defence of P. abies.

  • 77. Kännaste, A.
    et al.
    Laanisto, L.
    Pazouki, L.
    Copolovici, L.
    Suhorutšenko, M.
    Azeem, Muhammad
    KTH, Skolan för kemivetenskap (CHE), Kemi. COMSATS Institute of Information Technology, Pakistan.
    Toom, L.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi. University of Tartu, Estonia.
    Niinemets, Ü.
    Diterpenoid fingerprints in pine foliage across an environmental and chemotypic matrix: Isoabienol content is a key trait differentiating chemotypes2018Inngår i: Phytochemistry, ISSN 0031-9422, E-ISSN 1873-3700, Vol. 147, s. 80-88Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Diterpenoids constitute an important part of oleoresin in conifer needles, but the environmental and genetic controls on diterpenoid composition are poorly known. We studied the presence of diterpenoids in four pine populations spanning an extensive range of nitrogen (N) availability. In most samples, isoabienol was the main diterpenoid. Additionally, low contents of (Z)-biformene, abietadiene isomers, manoyl oxide isomers, labda-7,13,14-triene and labda-7,14-dien-13-ol were quantified in pine needles. According to the occurrence and content of diterpenoids it was possible to distinguish ‘non diterpenoid pines’ ‘high isoabienol pines’ ‘manoyl oxide – isoabienol pines’ and ‘other diterpenoid pines’. ‘Non diterpenoid pines’ ‘high isoabienol pines’ and ‘other diterpenoid pines’ were characteristic to the dry forest, yet the majority of pines (&gt;80%) of the bog Laeva represented ‘high isoabienol pines’. ‘Manoyl oxide – isoabienol pines’ were present only in the wet sites. Additionally, orthogonal partial least-squares analysis showed, that in the bogs foliar nitrogen content per dry mass (NM) correlated to diterpenoids. Significant correlations existed between abietadienes, isoabienol and foliar NM in ‘manoyl oxide – isoabienol pines’ and chemotypic variation was also associated by population genetic distance estimated by nuclear microsatellite markers. Previously, the presence of low and high Δ-3-carene pines has been demonstrated, but the results of the current study indicate that also diterpenoids form an independent axis of chemotypic differentiation. Further studies are needed to understand whether the enhanced abundance of diterpenoids in wetter sites reflects a phenotypic or genotypic response.

  • 78.
    Kännaste, Astrid
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Correlations between terpenes emitted by mini-plants of Norway spruce and Scots pineManuskript (Annet vitenskapelig)
  • 79.
    Kännaste, Astrid
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Nordenhem, Henrik
    Department of Ecology, Swedish University of Agricultural Sciences.
    Nordlander, Göran
    Department of Ecology, Swedish University of Agricultural Sciences.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Volatiles from a Mite-Infested Spruce Clone and Their Effects on Pine Weevil Behavior2009Inngår i: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 35, nr 10, s. 1262-1271Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    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.

  • 80.
    Kännaste, Astrid
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Vongvanich, Namphung
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Infestation by a Nalepella species induces emissions of alpha- and beta-farnesenes, (-)- linalool and aromatic compounds in Norway spruce clones of different susceptibility to the large pine weevil2008Inngår i: Arthropod-Plant Interactions, ISSN 1872-8855, Vol. 2, nr 1, s. 31-41Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The emissions of spruce grafts (Picea abies), caused by infestation of an acarid species of the genus Nalepella were investigated. Volatiles of three clones, both healthy and infested, with different susceptibility to the large pine weevil Hylobius abietis were collected by solid phase micro extraction (SPME) and analyzed by gas chromatograph coupled to mass-spectrometry (GC-MS). In addition, enantiomers of the main chiral compounds were separated by a two dimensional-gas chromatograph (2D-GC). In the characteristic flower-like fragrances emitted by the infested grafts large amounts of E-beta-farnesene, E, E-alpha-farnesene, (-)-linalool, methyl salicylate and minute amounts of benzyl alcohol, E-anethole, methyl benzoate, neral and geranial were found. All together, these compounds could explain the characteristic scent emitted by the infested seedlings. Large differences in the emissions of E-beta-farnesene, E, E-alpha-farnesene and methyl salicylate were found between but not within the clones.

  • 81.
    Kännaste, Astrid
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Zhao, Tao
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Lindström, A.
    Stattin, E.
    Långström, B.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Odors of Norway spruce (Picea abies L.) seedlings: Differences due to age and chemotype2013Inngår i: Trees, ISSN 0931-1890, E-ISSN 1432-2285, Vol. 27, nr 1, s. 149-159Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Small conifer seedlings (mini-seedlings) are less damaged by the large pine weevil Hylobius abietis (L.) (Coleoptera: Curculionidae) compared to conventional seedlings. Chemical difference between the seedling types is one possible explanation for this phenomenon. In the present paper, the emissions of volatile organic compounds (VOC) of 7- to 43-week-old Norway spruce [Picea abies (L.) Karst.] seedlings were analyzed. Collection and identification of the volatiles was made by solid phase micro-extraction and gas chromatography mass spectrometry (SPME-GC-MS). The enantiomers of α-pinene and limonene were separated in a two-dimensional GC (2D-GC). Most of the seedlings represented either a limonene- or a bornyl acetate-chemotype. Only minor changes in the volatile composition of the two types of seedlings were found during the first year. Age-related changes, however, were found in the volatiles released by wounded phloem where green leaf volatiles (GLVs) and borneol were the dominated VOC for young seedling. The attractive compound for the pine weevil, α-pinene, was first detected in the phloem emissions of 18- to 22-week-old seedlings. Different storage conditions of the seedlings during the winter/early spring-phase influenced the volatile composition in the phloem. High amount of GLVs was characteristic for the 43-week-old seedlings stored in naturally changing outdoor temperature, but not present in the seedlings winter-stored at a constant temperature of -4 °C. The possible role of these observed differences in odor emissions between seedlings of different age and physiological status for the feeding preferences of the large pine weevil is discussed.

  • 82.
    Kännaste, Astrid
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Zhao, Tao
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Lindström, Anders
    Dalarna University, School of Industrial Technology and Management.
    Stattin, Eva
    Dalarna University, School of Industrial Technology and Management.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Långström, Bo
    Swedish University of Agricultural Sciences, Department of Entomology.
    Odors of Norway spruce (Picea abies) seedlings: differences due to age and chemotype and their relevance for weevil resistanceManuskript (Annet vitenskapelig)
  • 83.
    Kännaste, Astrid
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Zhao, Tao
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Lindström, Anders
    Dalarna University, School of Industrial Technology and Management.
    Stattin, Eva
    Dalarna University, School of Industrial Technology and Management.
    Långström, Bo
    Swedish University of Agricultural Sciences, Department of Entomology.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Volatile emissions from pine seedlings: age-related changes and chemotypesManuskript (Annet vitenskapelig)
  • 84. Larsdotter Mellstrom, Helena
    et al.
    Friberg, Magne
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Murtazina, Rushana
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Palm, Mikael
    Wiklund, Christer
    Seasonal polyphenism in life history traits: time costs of direct development in a butterfly2010Inngår i: Behavioral Ecology and Sociobiology, ISSN 0340-5443, E-ISSN 1432-0762, Vol. 64, nr 9, s. 1377-1383Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Insects with two or more generations per year will generally experience different selection regimes depending on the season, and accordingly show seasonal polyphenisms. In butterflies, seasonal polyphenism has been shown with respect to morphology, life history characteristics and behaviour. In temperate bivoltine species, the directly developing generation is more time-constrained than the diapause generation, and this may affect various life history traits such as mating propensity (time from eclosion to mating). Here, we test whether mating propensity differs between generations in Pieris napi, along with several physiological parameters, i.e. male sex pheromone synthesis, and female ovigeny index and fecundity. As predicted, individuals of the directly developing generation-who have shorter time for pupal development-are more immature at eclosion; males take longer to synthesise the male sex pheromone after eclosion and take longer to mate than diapause generation males. Females show the same physiological pattern; the directly developing females lay fewer eggs than diapausing females during the first days of their life. Nevertheless, the directly developing females mate faster after eclosion than diapausing females, indicating substantial adult time stress in this generation and possibly an adaptive value of shortening the pre-reproductive period. Our study highlights how time stress can be predictably different between generations, affecting both life history and behaviour. By analysing several life history traits simultaneously, we adopt a multi-trait approach to examining how adaptations and developmental constraints likely interplay to shape these seasonal polyphenisms.

  • 85. Larsdotter-Mellstrom, Helena
    et al.
    Eriksson, Kerstin
    Liblikas, Ilme I.
    Wiklund, Christer
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi. University of Tartu, Estonia.
    Nylin, Soren
    Janz, Niklas
    Carlsson, Mikael A.
    It's All in the Mix: Blend-Specific Behavioral Response to a Sexual Pheromone in a Butterfly2016Inngår i: Frontiers in Physiology, ISSN 1664-042X, E-ISSN 1664-042X, Vol. 7, artikkel-id 68Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    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.

  • 86. Larsdotter-Mellström, Helena
    et al.
    Murtazina, Rushana
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Wiklund, Christer
    Timing of Male Sex Pheromone Biosynthesis in a Butterfly - Different Dynamics under Direct or Diapause Development2012Inngår i: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 38, nr 5, s. 584-591Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The life history traits and behavior of the butterfly are well-known, as the species is often used as a model organism for evolutionary and ecological studies. The species has two or more generations per year in the major part of its temperate distribution, and as different selection pressures affect the different generations, both behavioral and physiological seasonal polyphenisms have been shown previously. Here, we explored the dynamics of male sex pheromone production. The two generations are shown to have significantly different scent compositions early in life; the direct developers-who have shorter time for pupal development-need the first 24 hr of adult life after eclosion to synthesize the sex pheromone citral (geranial and neral 1:1)-whereas the diapausing individuals who have spent several months in the pupal stage eclose with adult scent composition. Resource allocation and biosynthesis also were studied in greater detail by feeding butterflies C-13 labeled glucose either in the larval or adult stage, and recording incorporation into geranial, neral, and other volatiles produced. Results demonstrate that the pheromone synthesized by newly eclosed adult males is based on materials ingested in the larval stage, and that adult butterflies are able to synthesize the pheromone components geranial and neral and the related alcohols also from adult intake of glucose. In summary, our study shows that time-stress changes the timing in biosynthesis of the complete pheromone between generations, and underpins the importance of understanding resource allocation and the physiological basis of life history traits.

  • 87. Legrand, S.
    et al.
    Nordlander, G.
    Nordenhem, H.
    Borg-Karlson, Anna-Karin
    KTH, Tidigare Institutioner, Kemi.
    Unelius, C. R.
    Hydroxy-methoxybenzoic methyl esters: Synthesis and antifeedant activity on the pine weevil, Hylobius abietis2004Inngår i: Zeitschrift für Naturforschung. B, A journal of chemical sciences, ISSN 0932-0776, E-ISSN 1865-7117, Vol. 59, nr 7, s. 829-835Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The pine weevil Hylobius abietis (L.) (Coleoptera: Curculionidae) feeds on the bark of coniferous seedlings and is the economically most important forestry restocking pest in large parts of Europe. Substances with an antifeedant effect may offer an environmentally friendly alternative to insecticides for the protection of planted seedlings. Bioassays were performed on commercial and synthetic methyl hydroxy-methoxybenzoates in order to determine their possible antifeedant activity. Two methyl hydroxy-methoxybenzoates were synthesized by esterification and mono-O-methylation of two dihydroxybenzoic acids. A regioselective protection-deprotection strategy was used in the synthetic pathway of the other non-commercial esters, esterification and selective pivaloylation of the less-hindered hydroxyl group of other commercial dihydroxybenzoic acids gave diester intermediates, which then were O-methylated before methanolysis of the pivaloyl group which yielded the desired non-commercial methyl hydroxy-methoxybenzoates. The five synthesized methyl hydroxy-methoxybenzoic esters were complemented with commercial samples of the five other isomers of methyl hydroxy-methoxybenzoate and spectrometric data were collected for the complete set of isomers. All ten isomers were tested for their antifeedant effect on the pine weevil. The effect varied considerably among the hydroxy-methoxybenzoic esters. Methyl 2-hydroxy-3-methoxybenzoate showed the highest effect and may thus be a candidate for practical use in pine weevil pest management.

  • 88. Liblikas, Ilme
    et al.
    Mozuraitis, Raimondas
    Santangelo, Ellen M.
    Noreika, Remigijus
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Syntheses, Characterizations, and Biological Activities of Tetradeca-4,8-dien-1-yl Acetates as Sex Attractants of Leaf-Mining Moth of the Genus Phyllonorycter (Lepidoptera: Gracillariidae)2009Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The four possible isomers of tetradeca-4,8-dien-1-yl acetate and corresponding alcohols were synthesized stereoselectively by synthetic routes employing Wittig coupling reaction for the preparation of (Z,E)- and (Z,Z)-isomers, and alkylation of terminal alkynes for the preparation of (E,E)- and (E,Z)isomers as the key steps. Synthetic products were characterized by C-13- and H-1-NMR spectroscopy as well as mass-spectrometric methods, All four isomers gave distinctive mass spectra where m/z 81 fragments clearly dominated. Elution order, followed by retention index presented in parenthesis, of tetradeca-4,8-dien-1-ols was determined as (Z,Z) (2082.1), (Z,E) (2082.8), (E,E) (2083.1), and (E,Z) (2083.2) from unpolar SPB-1 column, and as (E,E) (2210.2), (Z,E) (2222.1), (E,Z) (2223.4), and (Z,Z) (2224.7) from polar DB-WAX column. The isomers of tetradeca-4,8-dien-1-yl acetates eluted in the order of (Z,Z) (2176.1), (Z,E) (2178.4), (E,Z) (2185.9), and (E,E) (2186.4) from SPB-1, and (Z,E) (2124.3), (E,E) (2157.7), (Z,Z) (2128.9), and (E,Z) (2135.9) from DB-WAX columns. Field-screening tests for attractiveness of tetradeca-4,8-dien-1-yl acetates revealed that (4Z,8E)-tetradeca-4,8-dien-1-yl acetate significantly attracted Phyllonorycter coryli and Chrysoesthia drurella males. (4E,8E)-Tetradeca-4,8-dien-1-yl acetate was the most efficient attractant for Ph. esperella and Ph. saportella males, and (4E,8Z)-tetradeca-4,8-dien-1-yl acetate was attractive to Ph. cerasicolella males.

  • 89.
    Lindh, Jenny
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Faye, I.
    Transstadial and horizontal transfer of bacteria within a colony of Anopheles gambiae (Diptera: Culicidae) and oviposition response to bacteria-containing water2008Inngår i: Acta Tropica, ISSN 0001-706X, E-ISSN 1873-6254, Vol. 107, nr 3, s. 242-250Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In a paratransgenic approach, genetically modified bacteria are utilized to kill the parasite in the vector gut. A critical component for paratransgenics against malaria is how transgenic bacteria can be introduced and then kept in a mosquito population. Here, we investigated transstadial and horizontal transfer of bacteria within an Anopheles gambiae mosquito colony with the focus on spiked breeding sites as a possible means of introducing bacteria to mosquitoes. A Pantoea stewartii strain, previously isolated from An. gambiae, marked with a green fluorescent protein (GFP), was introduced to mosquitoes in different life stages. The following life stages or older mosquitoes in the case of adults were screened for bacteria in their guts. In addition to P. stewartii other bacteria were isolated from the guts: these were identified by 16S rRNA sequence analysis and temporal temperature gradient gel electrophoresis (TTGE). Bacteria were transferred from larvae to pupae but not from pupae to adults. The mosquitoes were able to take up bacteria from the water they emerged from and transfer the same bacteria to the water they laid eggs in. Eliza-bethkingia meningoseptica was more often isolated from adult mosquitoes than P. stewartii. A bioassay was used to examine An. gambiae oviposition responses towards bacteria-containing solutions. The volatiles emitted from the solutions were sampled by headspace-solid phase microextraction (SPME) and identified by gas chromatography and mass spectrometry (GC-MS) analysis. P. stewartii but not E. meningoseptica mediated a positive oviposition response. The volatiles emitted by P stewartii include indole and 3-methyl-1 -butanol, which previously have been shown to affect An. gambiae mosquito behaviour. E. meningoseptica emitted indole but not 3-methyl-1 -butanol, when suspended in saline. Taken together, this indicates that it may be possible to create attractive breeding sites for distribution of genetically modified bacteria in the field in a paratransgenic approach against malaria. Further research is needed to determine if the bacteria are also transferred in the same way in nature.

  • 90.
    Lindh, Jenny
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Kännaste, Astrid
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Knols, B. G. J.
    Faye, Ingrid
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Oviposition Responses of Anopheles gambiae s.s. (Diptera: Culicidae) and Identification of Volatiles from Bacteria-Containing Solutions2008Inngår i: Journal of medical entomology, ISSN 0022-2585, E-ISSN 1938-2928, Vol. 45, nr 6, s. 1039-1049Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study, a dual-choice oviposition bioassay was used to screen responses of gravid An. gambiae toward 17 bacterial species, previously isolated from Anopheles gambiae s.l. (Diptera: Culicidae) midguts or oviposition sites. The 10 isolates from oviposition sites have been identified by phylogenetic analyses of their 16S rRNA genes. Eight of the 10 isolates were gram-positive, out of which six belonged to the Bacilli class. Solid phase microextraction and gas chromatography coupled to mass spectrometry (GC-MS) were used to identify the volatiles emitted From the bacterial isolates, Aromatic and aliphatic alcohols, aliphatic ketones, alkylpyrazines, dimethyl oligosulfides, and indole were among the chemical compounds identified from the headspace above bacteria-containing saline. The mosquitoes laid significantly more eggs in six of the bacteria-containing solutions compared with the sterile solution. These six bacteria did not emit any compounds in common that could explain the positive oviposition response. Instead. the bacteria were grouped according to principal component analysis (PCA) based on the relative amouts of volatile emitted. The PCA-plots facilitated the identification of 13 putative oviposition attractants for An. gambiae mosquitoes.

  • 91.
    Lindh, Jenny M.
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Okal, M. N.
    Herrera-Varela, M.
    Borg-Karlson, Anna Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Torto, B.
    Lindsay, S. W.
    Fillinger, U.
    Discovery of an oviposition attractant for gravid malaria vectors of the Anopheles gambiae species complex2015Inngår i: Malaria Journal, ISSN 1475-2875, E-ISSN 1475-2875, Vol. 14, nr 1, artikkel-id 119Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: New strategies are needed to manage malaria vector populations that resist insecticides and bite outdoors. This study describes a breakthrough in developing 'attract and kill' strategies targeting gravid females by identifying and evaluating an oviposition attractant for Anopheles gambiae s.l. Methods: Previously, the authors found that gravid An. gambiae s.s. females were two times more likely to lay eggs in lake water infused for six days with soil from a natural oviposition site in western Kenya compared to lake water alone or to the same but autoclaved infusion. Here, the volatile chemicals released from these substrates were analysed with a gas-chromatograph coupled to a mass-spectrometer (GC-MS). Furthermore, the behavioural responses of gravid females to one of the compounds identified were evaluated in dual choice egg-count bioassays, in dual-choice semi-field experiments with odour-baited traps and in field bioassays. Results: One of the soil infusion volatiles was readily identified as the sesquiterpene alcohol cedrol. Its widespread presence in natural aquatic habitats in the study area was confirmed by analysing the chemical headspace of 116 water samples collected from different aquatic sites in the field and was therefore selected for evaluation in oviposition bioassays. Twice as many gravid females were attracted to cedrol-treated water than to water alone in two choice cage bioassays (odds ratio (OR) 1.84; 95% confidence interval (CI) 1.16-2.91) and in experiments conducted in large-screened cages with free-flying mosquitoes (OR 1.92; 95% CI 1.63-2.27). When tested in the field, wild malaria vector females were three times more likely to be collected in the traps baited with cedrol than in the traps containing water alone (OR 3.3; 95% CI 1.4-7.9). Conclusion: Cedrol is the first compound confirmed as an oviposition attractant for gravid An. gambiae s.l. This finding paves the way for developing new 'attract and kill strategies' for malaria vector control.

  • 92.
    Lopez-Goldar, Xose
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH). CSIC, Mision Biol Galicia, Pontevedra, Spain.;Ohio State Univ, Dept Plant Pathol, Columbus, OH 43210 USA.;INIA, Forest Res Ctr, Dept Forest Ecol & Genet, Madrid, Spain..
    Villari, Caterina
    Ohio State Univ, Dept Plant Pathol, Columbus, OH 43210 USA.;Univ Georgia, Daniel B Warnell Sch Forestry & Nat Resources, Athens, GA 30602 USA..
    Bonello, Pierluigi
    Ohio State Univ, Dept Plant Pathol, Columbus, OH 43210 USA..
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Organisk kemi.
    Grivet, Delphine
    INIA, Forest Res Ctr, Dept Forest Ecol & Genet, Madrid, Spain.;Univ Valladolid, INIA, Sustainable Forest Management Res Inst, Palencia, Spain..
    Zas, Rafael
    CSIC, Mision Biol Galicia, Pontevedra, Spain..
    Sampedro, Luis
    CSIC, Mision Biol Galicia, Pontevedra, Spain..
    Inducibility of Plant Secondary Metabolites in the Stem Predicts Genetic Variation in Resistance Against a Key Insect Herbivore in Maritime Pine2018Inngår i: Frontiers in Plant Science, ISSN 1664-462X, E-ISSN 1664-462X, Vol. 9, artikkel-id 1651Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Resistance to herbivores and pathogens is considered a key plant trait with strong adaptive value in trees, usually involving high concentrations of a diverse array of plant secondary metabolites (PSM). Intraspecific genetic variation and plasticity of PSM are widely known. However, their ecology and evolution are unclear, and even the implication of PSM as traits that provide direct effective resistance against herbivores is currently questioned. We used control and methyl jasmonate (MJ) induced clonal copies of genotypes within families from ten populations of the main distribution range of maritime pine to exhaustively characterize the constitutive and induced profile and concentration of PSM in the stem phloem, and to measure insect herbivory damage as a proxy of resistance. Then, we explored whether genetic variation in resistance to herbivory may be predicted by the constitutive concentration of PSM, and the role of its inducibility to predict the increase in resistance once the plant is induced. We found large and structured genetic variation among populations but not between families within populations in resistance to herbivory. The MJ-induction treatment strongly increased resistance to the weevil in the species, and the genetic variation in the inducibility of resistance was significantly structured among populations, with greater inducibility in the Atlantic populations. Genetic variation in resistance was largely explained by the multivariate concentration and profile of PSM at the genotypic level, rather than by bivariate correlations with individual PSM, after accounting for genetic relatedness among genotypes. While the constitutive concentration of the PSM blend did not show a clear pattern of resistance to herbivory, specific changes in the chemical profile and the increase in concentration of the PSM blend after MJ induction were related to increased resistance. To date, this is the first example of a comprehensive and rigorous approach in which inducibility of PSM in trees and its implication in resistance was analyzed excluding spurious associations due to genetic relatedness, often overlooked in intraspecific studies. Here we provide evidences that multivariate analyses of PSM, rather than bivariate correlations, provide more realistic information about the potentially causal relationships between PSM and resistance to herbivory in pine trees.

  • 93.
    Lundborg, Lina
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Fedderwitz, Frauke
    Department of Ecology, Swedish University of Agricultural Sciences.
    Björklund, Niklas
    Department of Ecology, Swedish University of Agricultural Sciences.
    Nordlander, Göran
    Department of Ecology, Swedish University of Agricultural Sciences.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Conifer chemical defenses influence meal properties of the pine weevil Hylobius abietisManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    Chemical defenses of conifers can be experimentally activated to respond more efficiently to feeding damage by insects. One chemical elicitor that triggers plant defenses, and thereby protects conifers, is methyl jasmonate (MeJA). However, there is little known about the associations between MeJA-induced conifer defenses, and the meal properties of phytophagous insects. To address this knowledge gap, we have analyzed relations between volatile contents of Scots pine (Pinus sylvestris L.) tissues, and meal properties of the pine weevil (Hylobius abietis (L.)). Phloem and needles (both weevil target tissues) from MeJA-treated and control seedlings were extracted by n-hexane and analyzed by two-dimensional gas chromatography-mass spectrometry (2D GC-MS). Feeding of pine weevils on seedlings from the same batches were video-recorded to determine meal properties. Multivariate statistical analyses showed that phloem and needle contents of MeJA-treated seedlings had different volatile compositions from the control seedlings. Levels of (+)-α-pinene were high, and levels of the antifeedant 2-phenylethanol were low, in phloem of control seedlings with feeding damage. Accordingly, pine weevils fed more slowly and had shorter meals on MeJA-treated seedlings. In addition, the chemical compositions of phloem and needles – and accordingly weevil meal durations on them – were more similar in MeJA-treated seedlings than in controls. The results illustrate that detailed knowledge of insect responses can help efforts to identify and elucidate specific roles of resistance agents in complex chemical profiles.

  • 94.
    Lundborg, Lina
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Fedderwitz, Frauke
    Department of Ecology, Swedish University of Agricultural Sciences.
    Björklund, Niklas
    Department of Ecology, Swedish University of Agricultural Sciences.
    Nordlander, Göran
    Department of Ecology, Swedish University of Agricultural Sciences.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Induced defenses change the chemical composition of pine seedlings and influence meal properties of the pine weevil Hylobius abietis2016Inngår i: Phytochemistry, ISSN 0031-9422, E-ISSN 1873-3700, Vol. 130, s. 99-105Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The defense of conifers against phytophagous insects relies to a large extent on induced chemical defenses. However, it is not clear how induced changes in chemical composition influence the meal properties of phytophagous insects (and thus damage rates). The defense can be induced experimentally with methyl jasmonate (MeJA), which is a substance that is produced naturally when a plant is attacked. Here we used MeJA to investigate how the volatile contents of Scots pine (Pinus sylvestris L.) tissues influence the meal properties of the pine weevil (Hylobius abietis (L.)). Phloem and needles (both weevil target tissues) from MeJA-treated and control seedlings were extracted by n-hexane and analyzed by two-dimensional gas chromatography-mass spectrometry (2D GC-MS). The feeding of pine weevils on MeJA-treated and control seedlings were video-recorded to determine meal properties. Multivariate statistical analyses showed that phloem and needle contents of MeJA-treated seedlings had different volatile compositions compared to control seedlings. Levels of the pine weevil attractant (+)-α-pinene were particularly high in phloem of control seedlings with feeding damage. The antifeedant substance 2-phenylethanol occurred at higher levels in the phloem of MeJA-treated than in control seedlings. Accordingly, pine weevils fed slower and had shorter meals on MeJA-seedlings. The chemical compositions of phloem and needle tissues were clearly different in control seedlings but not in the MeJA-treated seedlings. Consequently, meal durations of mixed meals, i.e. both needles and phloem, were longer than phloem meals on control seedlings, while meal durations on MeJA seedlings did not differ between these meal contents. The meal duration influences the risk of girdling and plant death. Thus our results suggest a mechanism by which MeJA treatment may protect conifer seedlings against pine weevils.

  • 95.
    Lundborg, Lina
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Nordlander, Goran
    Bjorklund, Niklas
    Nordenhem, Henrik
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Methyl Jasmonate-Induced Monoterpenes in Scots Pine and Norway Spruce Tissues Affect Pine Weevil Orientation2016Inngår i: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 42, nr 12, s. 1237-1246Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In large parts of Europe, insecticide-free measures for protecting conifer plants are desired to suppress damage by the pine weevil Hylobius abietis (L.). Treatment with methyl jasmonate (MeJA), a chemical elicitor already used in crop production, may enhance expression of chemical defenses in seedlings in conifer regenerations. However, in a previous experiment, MeJA treatment resulted in substantially better field protection for Scots pine (Pinus sylvestris L.) than for Norway spruce (Picea abies (L.) Karst.). Hypothesizing that the variations may be at least due partly to volatiles released by MeJA-treated seedlings and their effects on pine weevil orientation, we examined tissue extracts of seedlings (from the same batches as previously used) by two-dimensional GC-MS. We found that the MeJA treatment increased contents of the monoterpene (-)-beta-pinene in phloem (the weevil's main target tissue) of both tree species, however, the (-)-beta-pinene/(-)-alpha-pinene ratio increased more in the phloem of P. sylvestris. We also tested the attractiveness of individual monoterpenes found in conifer tissues (needles and phloem) for pine weevils using an arena with traps baited with single-substance dispensers and pine twigs. Trap catches were reduced when the pine material was combined with a dispenser releasing (-)-beta-pinene, (+)-3-carene, (-)-bornyl acetate or 1,8-cineole. However, (-)-alpha-pinene did not have this effect. Thus, the greater field protection of MeJA-treated P. sylvestris seedlings may be due to the selective induction of increases in contents of the deterrent (-)-beta-pinene, in contrast to strong increases in both non-deterrent (-)-alpha-pinene and the deterrent (-)-beta-pinene in P. abies seedlings.

  • 96.
    Lundborg, Lina
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Nordlander, Göran
    Department of Ecology, Swedish University of Agricultural Sciences.
    Björklund, Niklas
    Department of Ecology, Swedish University of Agric.
    Nordenhem, Henrik
    Department of Ecology, Swedish University of Agric.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Methyl jasmonate-induced monoterpenes in Scots pine and Norway spruce tissues affect pine weevil orientationManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    In large parts of Europe insecticide-free measures for protecting conifer plants are desired to suppress damage by the pine weevil Hylobius abietis (L.). Treatment with methyl jasmonate (MeJA), a chemical elicitor already used in crop production, may enhance expression of chemical defenses in seedlings in conifer regenerations. However, in a previous experiment MeJA treatment resulted in substantially better field protection for Scots pine (Pinus sylvestris L.) than for Norway spruce (Picea abies (L.) Karst.). Hypothesizing that the variations may be at least partly due to volatiles released by MeJA-treated seedlings and their effects on pine weevil orientation, we examined tissue extracts of seedlings (from the same batches as previously used) by two-dimensional GC-MS. We found that the MeJA treatment increased contents of the monoterpene (-)-β-pinene in phloem (the weevil’s main target tissue) of both tree species, however, the (-)-β-pinene/(-)-α-pinene ratio increased more in the phloem of P. sylvestris. We also tested the attractiveness of individual monoterpenes found in conifer tissues (needles and phloem) for pine weevils using an arena with traps baited with single-substance dispensers and pine twigs. Trap catches were reduced when the pine material was combined with a dispenser releasing (-)-β-pinene, (+)-3-carene, (-)-bornyl acetate or 1,8-cineole. However, (-)-α-pinene did not have this effect. Thus, the greater field protection of MeJA-treated P. sylvestris seedlings may be due to the selective induction of increases in contents of the deterrent (-)-β-pinene, in contrast to strong increases in both non-deterrent (-)-α-pinene and the deterrent (-)-β-pinene in P. abies seedlings.

  • 97.
    Lundborg, Lina
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH). CDEng Aquaculture.
    Sampedro, Luis
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Zas, Rafael
    Effects of methyl jasmonate on the concentration of volatile terpenes in tissues of Maritime pine and Monterey pine and its relation to pine weevil feeding2018Inngår i: Trees, ISSN 0931-1890, E-ISSN 1432-2285Artikkel i tidsskrift (Fagfellevurdert)
  • 98.
    Lundborg, Lina
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Sampedro, Luis
    Grupo de Xenetica e Ecoloxía da Resistencia en Coníferas, Misión Biológica de Galicia (MBG-CSIC), Pontevedra, Spain.
    Zas, Rafael
    Grupo de Xenetica e Ecoloxía da Resistencia en Coníferas, Misión Biológica de Galicia (MBG-CSIC), Pontevedra, Spain.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Constitutive and MeJA-induced terpenes in Pinus pinaster and Pinus radiata in relation to Hylobius abietisManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    The feeding preference of the pine weevil to Maritime pine (Pinus pinaster Ait.) and Monterey pine (Pinus radiata D. Don) differ in laboratory tests and in the field: Can this be explained by the volatile compounds released by the seedlings? Understanding the interaction between the chemical defenses of young pines and feeding preferences of the pine weevil (Hylobius abietis (L.)) may improve protection methods of conifer seedlings in Europe and Asia. In order to increase the resistance of seedlings of P. pinaster and P. radiata, these were treated with the chemical elicitor methyl jasmonate (MeJA). The effects of the MeJA treatments on the amounts and composition of volatile terpenes in tissues (needles and phloem) were investigated by extracting these in hexane, whereafter the volatile constituents of the extracts were separated and identified by gas chromatography-mass spectrometry (GC-MS). In addition, the most abundant monoterpenes (α-pinene and β-pinene) were separated on a chiral column in their enantiomers. Already at the lowest concentration of MeJA treatment, 5 mM, the amounts of volatile terpenes in the needles of P. radiata increased and the seedling heights were reduced. In P. pinaster, on the other hand, no effect from the MeJA treatment was observed on the total volatile terpenes in the needles, and only at the strongest MeJA concentration, the seedling heights were affected. In the phloem of P. pinaster the composition of volatile contents, changed after MeJA treatment, showing a reduction in the (+)-α-pinene. In contrast, the amounts of (+)-α-pinene increased in P. radiata. In a previous study, controls and MeJA-treated pine seedlings, from the same MeJA treatment batches as in this study, were subjected to a field trial. In the field, the pine weevils preferred the seedlings of P. radiata over those of P. pinaster. We propose that the differences in induction of (+)-α-pinene may be important for explaining the differences in pine weevil feeding preferences.

  • 99. Luxova, A.
    et al.
    Urbanova, K.
    Valterova, I.
    Terzo, M.
    Borg-Karlson, Anna-Karin
    KTH, Tidigare Institutioner, Kemi.
    Absolute configuration of chiral terpenes in marking pheromones of bumblebees and cuckoo bumblebees2004Inngår i: Chirality, ISSN 0899-0042, E-ISSN 1520-636X, Vol. 16, nr 4, s. 228-233Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The absolute configurations of citronellol, 2,3-dihydrofamesol, and 2,3-dihydrofarnesal in male marking pheromones of seven species of bumblebees and cuckoo bumblebees were determined by enantioselective gas chromatography on a capillary column coated with 60% heptakis(2,3-di-O-acetyl-6-O-TBDMS)-beta-cyclodextrin in polysiloxane PS 268. Pure (-)-S-enantiomers of all three terpenes were found in the labial glands of all investigated specimens of the following species: Bombus (Bombus) terrestris, B. (Bombus) lucorum, B. (Pyrobombus) pratorum, B. (Pyrobombus) pyrenaeus, B. (Pyrobombus) jonellus, B. (Pyrobombus) impatiens, and the cuckoo bumblebee B. (Ashtonipsithyrus) bohemicus. Within species, specimens were collected at different localities and in different years. Except for 2,3-dihydrofamesol in B. terrestris, this is the first report on the absolute configuration of terpenes in marking pheromones of bumblebees.

  • 100.
    López-Goldar, Xosé
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Villari, C.
    Bonello, P.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Organisk kemi.
    Grivet, D.
    Sampedro, L.
    Zas, R.
    Genetic variation in the constitutive defensive metabolome and its inducibility are geographically structured and largely determined by demographic processes in maritime pine2019Inngår i: Journal of Ecology, ISSN 0022-0477, E-ISSN 1365-2745, Vol. 107, nr 5, s. 2464-2477Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Interspecific phenotypic variation in plant secondary metabolites (PSM) is often explained by biotic and abiotic factors. However, patterns of variation within species do not clearly fit the theoretical predictions. Exploring how genetics, environment and demographic processes shape such variation among and within populations is crucial for understanding evolution of PSM, particularly in long-lived plants such as forest trees. Here, we quantified genetic variation in PSM among and within populations, and explored drivers of local adaptation by studying the role of climate as a source of population differentiation in PSM of maritime pine. Constitutive profile and concentrations of 63 PSM and their herbivory-associated inducibility were determined in the bark of 130 clonally replicated genotypes with known familial structure from 10 populations covering the distribution range of the species. We compared neutral and quantitative population genetic differentiation of PSM (F ST and Q ST ). Also, we accounted for population genetic structure and kinship among individuals when exploring climate–trait relationships. We found large population differentiation and additive genetic variation in constitutive PSM. Many PSM were inducible, although very low genetic variation was observed with respect to their inducibility. Q ST –F ST comparisons suggest that differentiation of most diterpenes, monoterpenes, and phenolics can be explained by neutral demographic processes. Spatially heterogeneous selection across populations leading to local adaptation was only found for total constitutive sesquiterpenes and a few individual PSM. After accounting for population genetic structure, only the constitutive concentration of two sesquiterpenes showing signs of diversifying selection was predicted by climate, with decreasing concentrations along a growth-prone climatic gradient. Synthesis. Evolutionary patterns of plant secondary metabolites depended on their chemical nature, with neutral differentiation governing most plant secondary metabolites. Evidence of local adaptation was only found for total constitutive sesquiterpenes and a few individual plant secondary metabolites. The low genetic variation in the inducibility of plant secondary metabolites suggests a conserved model of defensive induction in this species. Since population differentiation linked to past demographic history could lead to false positives of adaptive differentiation signals, accounting for the genetic relatedness among populations is required to infer the environmental determinants of intraspecific genetic variation in putatively adaptive traits such as plant defences.

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