| 1. |
- Manrique, G., et al.
(författare)
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Chemical Communication in Chagas Disease Vectors. Source, Identity and Potential Function of Volatiles Released by the Metasternal and Brindleys Glands of Triatoma infestans Adults
- 2006
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Ingår i: Journal of Chemical Ecology. - : Springer. - 0098-0331 .- 1573-1561. ; 32:9, s. 2035-2052
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Tidskriftsartikel (refereegranskat)abstract
- Compounds from the metasternal and Brindley's glands of the blood-sucking bug, Triatoma infestans, were identified by solid phase microextraction (SPME) and gas chromatography-mass spectrometry. Volatile compounds released by adult bugs during copulation or after mechanical disturbance were also characterized. Six compounds were identified and found consistently in all samples from metasternal glands. The most abundant were 3-pentanone, 2-methylbutanol, 3-pentanol, and an unidentified compound. The metasternal gland blends did not differ qualitatively between sexes. Compounds found in Brindley's glands were short chain acids, alcohols, esters, and a ketone with no qualitative differences between sexes. Isobutyric acid was the main component of this blend, and two new confirmed compounds were described as products of these glands: 2-butanone and 2-methylbutyric acid. 3-Pentanone was collected from the headspace over 33% of the copulating pairs of T. infestans. Volatiles found in the headspace of disturbed T. infestans adults included short-chain fatty acids, alcohols, esters, and ketones, with no qualitative differences between sexes. Both types of glands apparently discharge their contents after disturbance. However, most of the volatiles released by bugs after disturbance came from Brindley's glands. The locomotor activity of fourth instars increased significantly after stimulation with the odors emitted by disturbed adults, as compared with larvae stimulated by the odor of undisturbed adults or by clean air. We also studied the directional behavioral response of fifth instars to the disturbance scent in a locomotion compensator. Larvae exposed to volatiles released by disturbed adults walked away from the direction of the odor. The results suggest that this blend or part of it functions as an alarm pheromone for T. infestans. We suggest that the metasternal glands of this species are involved both in the sexual and the alarm contexts, and that the Brindley's glands probably have both alarm and defensive roles.
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| 2. |
- Witzgall, P., et al.
(författare)
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Potential of a blend of E8,E10-120H and E8,E10-12Ac for mating disruption of codling moth, Cydia pomonella L (Lep, Tortricidae)
- 1996
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Ingår i: Journal of applied entomology. - : John Wiley & Sons. - 0931-2048 .- 1439-0418. ; 120:1-5, s. 611-614
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Tidskriftsartikel (refereegranskat)abstract
- Dispensers of E8,E10-12OH (codlemone), E8,E10-12Ac (codlemone acetate), or both dispenser types were placed on the corners of 100 m(2) and 300 m(2) plots within apple orchards. Communication disruption of male codling moths, Cydia pomonella, was monitored with pheromone traps in the centres of these plots. In the 300 m(2) plots, trap catch was reduced only by codlemone. In the 100 m(2) plots, trap catch was reduced in all three treatments, fewest males were caught in plots treated with both codlemone and codlemone acetate. Males were attracted to codlemone dispensers, they were also flying actively around the tree crowns, well above the dispensers. This behaviour was not observed in treatments with codlemone acetate, where male orientation flights were directed only towards the trap in the plot centre. The antagonistic effect of each of the four geometric isomers of codlemone acetate was shown by another trap test. Addition of 20% E,E-; E,Z-; Z,E- or Z8,Z10-12Ac decreased male attraction to traps baited with E8, E10-12OH.
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| 3. |
- Zhu, J. W., et al.
(författare)
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Identification of (Z)-4-tridecene from defensive secretion of green lacewing, Chrysoperla carnea
- 2000
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Ingår i: Journal of Chemical Ecology. - : Springer. - 0098-0331 .- 1573-1561. ; 26:10, s. 2421-2434
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Tidskriftsartikel (refereegranskat)abstract
- We report the identification of a defensive secretion from the green lacewing, Chrysoperla carnea. By using combined gas chromatography-electroantennographic detection (GC-EAD), we found one major compound in the solvent extract of this secretion that elicited a significant EAD response from the antenna. Based upon its characteristic fragments from gas chromatography-mass spectrometry (GC-MS) analysis, the compound was identified as a tridecene. Dimethyldisulfide derivatization suggested that a double bond was located between positions 4 and 5 in the carbon chain. Thus, the compound was tentatively identified as a 4-tridecene. Coinjection of the extract with a mixture of the Z or E form of the synthetic 4-tridecene revealed that the unknown was (Z)-4-tridecene. EAG dose-responses showed a direct correlation to dose. Single sensillum recordings from sensilla trichodea situated on the antennae suggested the presence of receptor neurons specifically responding to this compound. An arrestment behavior was observed when tested in the Y-tube olfactometer. Preliminary field trapping results indicate that the compound is an antagonist to attraction. The avoidance behavior of predatory ants, observed when tested with the synthetic compound of this secretion further suggested a defensive function.
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| 4. |
- Bäckman, A. C., et al.
(författare)
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Antennal response of codling moth males, Cydia pomonella L. (Lepidoptera: Tortricidae), to the geometric isomers of codlemone and codlemone acetate
- 2000
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Ingår i: Journal of Comparative Physiology A. Sensory, neural, and behavioral physiology. - : Springer. - 0340-7594 .- 1432-1351. ; 186:6, s. 513-519
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Tidskriftsartikel (refereegranskat)abstract
- Single sensillum recordings from Cydia pomonella male antennae showed three different types of receptor neurons. The most abundant type was most sensitive to the main pheromone compound (E,E)-8,10-dodecadienol, while its response to the geometric isomers E,Z, Z,E and Z,Z was comparable to a tenfold lower dose of (E,E)-8,10-dodecadienol. This neuron type also responded to the four behaviorally antagonistic isomers of (Delta,Delta)-8,10-dodecadienyl acetate, among which it was most sensitive to the E,E isomer. Cross-adaptation studies showed that these compounds were all detected by the same receptor neuron type. Receptor neurons specifically tuned to (E,Z) or (Z,Z)-8,10-dodecadienol were not found, although these two compounds are behaviorally active. A second type of receptor neuron responded to all isomers of (Delta,Delta)-8,10-dodecadienyl acetate and was most sensitive to the E,E isomer. This neuron type did not respond to any of the isomers of (Delta,Delta)-8,10-dodecadienol. A third receptor neuron type was highly sensitive to the plant compound alpha-farnesene. The finding that the receptor neuron type tuned to the main pheromone compound responded even to strong behavioral antagonists aids the interpretation of ongoing behavioral studies for the development of the mating disruption technique in codling moth.
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| 5. |
- El-Sayed, Ashraf M., et al.
(författare)
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Feeding Volatiles of Larval Sparganothis pilleriana (Lepidoptera:Tortricidae) Attract Heterospecific Adults o the European Grapevine Moth
- 2021
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Ingår i: Environmental Entomology. - : Oxford University Press. - 0046-225X .- 1938-2936. ; 50:6, s. 1286-1293
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Tidskriftsartikel (refereegranskat)abstract
- Plants release volatiles in response to caterpillar feeding.These herbivore-induced plant volatiles (HIPVs) attract natural enemies of the herbivores and repel or attract conspecific adult herbivores in a tri-trophic interaction which has been considered to be an indirect plant defense against herbivores. Recently, we demonstrated the attraction of male and female European grapevine moth, Lobesia botrana (Denis & Schiffermuller) (Lepidoptera: Tortricidae) to a blend of phenylacetonitrile and acetic acid, two compounds identified as HIPVs in heterospecific apple-leafroller interactions. The ecological basis of our findings is not clearly understood.Thus, this work was undertaken to investigate HIPVs in the grapevine-leafroller interaction and study the response of heterospecific adults L. botrana, to these volatiles. We collected headspace volatiles emitted from uninfested grapevines and grapevines infested with larvae of a generalist herbivore, the grapevine leafroller moth, Sparganothis pilleriana (Denis & Schiffermuller), and analyzed them using gas chromatography/mass spectrometry. Infested grape leaves released three compounds (phenylacetonitrile, indole, and 2-phenylethanol) not found from uninfested leaves. Nine different blends, comprising a full factorial set of the three oompou nds with each blend containing acetic acid, were tested in a field-cage trial. Only lures containing phenylacetonitrile caused a significant increase in trap catches compared to the other lures and blank traps. Electroantennographic tests show that L botrana can detect the compounds. The results confirm our hypothesis that phenylacetonitrile is released during grapevines infestation with herbivores, and attracts adult L. botrana.
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| 6. |
- Franco, Thiago A., et al.
(författare)
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Reverse chemical ecology-based approach leading to the accidental discovery of repellents for Rhodnius prolixus, a vector of Chagas diseases refractory to DEET
- 2018
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Ingår i: Insect Biochemistry and Molecular Biology. - : Elsevier. - 0965-1748 .- 1879-0240. ; 103, s. 46-52
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Tidskriftsartikel (refereegranskat)abstract
- Rhodnius prolixus is one of the most important vectors of Chagas disease in Central and South America for which repellents and attractants are sorely needed. Repellents like DEET, picaridin, and IR3535 are widely used as the first line of defense against mosquitoes and other vectors, but they are ineffective against R. prolixus. Our initial goal was to identify in R. prolixus genome odorant receptors sensitive to putative sex pheromones. We compared gene expression of 21 ORs in the R. prolixus genome, identified 4 ORs enriched in male (compared with female) antennae. Attempts to de-orphanize these ORs using the Xenopus oocyte recording system showed that none of them responded to putative sex pheromone constituents. One of the them, RproOR80, was sensitive to 4 compounds in our panel of 109 odorants, namely, 2-heptanone, gamma-octalactone, acetophenone, and 4-methylcychohexanol. Interestingly, these compounds, particularly 4-methylcyclohexanol, showed strong repellency activity as indicated not only by a significant decrease in residence time close to a host, but also by a remarkable reduction in blood intake. 4-Methylcyclohexanol-elicited repellency activity was abolished in RNAi-treated insects. In summary, our search for pheromone receptors led to the discovery of repellents for R. prolixus.
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| 7. |
- Karlson, J., et al.
(författare)
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Inhibition of tumor cell growth by monoterpenes in vitro : Evidence of a Ras-independent mechanism of action
- 1996
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Ingår i: Anti-Cancer Drugs. - : Ovid Technologies (Wolters Kluwer Health). - 0959-4973 .- 1473-5741. ; 7:4, s. 422-429
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Tidskriftsartikel (refereegranskat)abstract
- (+)-Limonene (d-limonene) and related monoterpenes show chemopreventive activity against rodent mammary carcinoma and inhibit the growth of cancer cells in vitro, One suggested mechanism for the anti-tumorigenic effect of (+)-limonene is inhibition of the post-translational isoprenylation of growth controlling Pas oncoproteins. We have here examined the growth inhibitory effects of (+)-limonene and other related monoterpenes on PANC-1 pancreas carcinoma cells (carrying a K-ras mutation) and on 12V-H-ras-transformed rat fibroblasts, (+)- and (-)-perillyl alcohol, 7-methyl-perillyl alcohol, (+)-limonene oxide and (+)-perillic acid methyl ester were all found to efficiently inhibit cell growth at 1 mM, whereas (+)-limonene caused an approximately 50% growth reduction at 5 mM, Whereas BZA-BB, an inhibitor of Ras farnesyl transferase, was found to induce morphological reversion of 12v-H-ras-transformed cells, (+)-perillyl alcohol and (+)-limonene did not induce reversion. Furthermore, monoterpenes did not decrease MAP kinase enzyme activity or collagenase promoter activity in PANC-1 cells, two functions known to be down-stream from Pas, We conclude that although effective in inhibiting the growth of tumor cells harboring activated res oncogenes, limonene and (+)-perillyl alcohol are unlikely to act by inhibiting Ras function.
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| 8. |
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| 9. |
- Sullivan, Nicola J., et al.
(författare)
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Developing a mealybug pheromone monitoring tool to enhance IPM practices in New Zealand vineyards
- 2023
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Ingår i: Journal of Pest Science. - : Springer. - 1612-4758 .- 1612-4766. ; 96, s. 29-39
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Tidskriftsartikel (refereegranskat)abstract
- Mealybugs are phloem-feeding insects found on many crops worldwide. In New Zealand vineyards, they transmit the economically important Grapevine leafroll-associated virus 3 (GLRaV-3). For some mealybug species, synthetic sex pheromones have been commercialised, and are used as monitoring tools. The mealybugs Pseudococcus longispinus and Pseudococcus calceolariae are major pests in many New Zealand vineyards. We present work on the development of a combined P. longispinus and P. calceolariae pheromone lure. The optimal dose for monitoring P. longispinus was found to be 10 mu g of the (S)-(+)-enantiomer, either alone or in the racemic mixture. Addition of the corresponding alcohol did not improve trap catch of P. longispinus. Both the P. longispinus and the P. calceolariae pheromone lures remained active in the field for 90 days. Combining the 2 species' pheromones had no negative effects on male mealybug trap catch for either species. We conclude that the pheromone ester alone is the best lure for the male P. longispinus. Combining the two mealybug species' pheromones into a single lure provides the New Zealand viticultural industry with an efficient monitoring tool. Late-vintage deployment of baited lures will provide information on mealybug abundance and local distribution that will inform the scope of future insecticide programmes, to target areas based on need rather than an area-wide application by default.
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| 10. |
- Unelius, C. Rikard, et al.
(författare)
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Comparisons of traps and lures for monitoring grass grub Costelytra zealandica
- 2008
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Ingår i: New Zealand Plant Protection. - : New Zealand Plant Protection Society. - 1175-9003 .- 1179-352X. ; 61, s. 215-221
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Tidskriftsartikel (refereegranskat)abstract
- Phenol the attractant pheromone of adult males of the native New Zealand grass grub Costelytra zealandica (White) is produced in the beetles as the result of bacterial degradation of tyrosine A lure consisting of a resin impregnated with phenol has been widely used to monitor male beetle flight activity The present formulation is highly attractive for the first week in the field but then loses activity rapidly A number of phenolcontaining formulations were tested to improve the lure A new formulation gave lower catches that were more stable with time producing data more suitable for population density estimation Phenylacetaldehyde a bacterial metabolite of phenylalanine was tested as a possible synergist to phenol Field results showed that this floral compound exhibited no behaviourallyactive properties to grass grubs when tested together with phenol Catches with water traps were compared with those in sticky delta and flat delta traps in two vineyards and in pasture Water traps caught four times more beetles
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