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Sample records for volatile pheromone produced

  1. Evidence for volatile male-produced pheromone in banana weevilCosmopolites sordidus.

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    Budenberg, W J; Ndiege, I O; Karago, F W

    1993-09-01

    Females of the banana weevil,Cosmopolites sordidus, were attracted to and made longer visits to live conspecific males, trapped volatiles from males, and dissected male hindguts in a still-air olfactometer. Male weevils were attracted to volatiles trapped from males and made longer visits to live males and volatiles from males. Live females, collected volatiles from females and female hindguts, elicited small or no behavioral responses from either sex. Electroantennogram (EAG) responses from both male and female antennae were elicited by collected volatiles from males and by dichloromethane extracts of male hindguts and bodies but not by surface washes of males. No significant EAG responses were given to equivalent material from females. It is therefore suggested that male banana weevils release an aggregation pheromone via their hindgut.

  2. Different bioassays for investigating orientation responses of the banana weevil, Cosmopolites sordidus, show additive effects of host plant volatiles and a synthetic male-produced aggregation pheromone

    NARCIS (Netherlands)

    Tinzaara, W.; Dicke, M.; Huis, van A.; Loon, van J.A.; Gold, C.S.

    2003-01-01

    Three different bioassay methods to investigate the orientation behaviour of the banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae), to host plant volatiles and a synthetic pheromone (cosmolure+) were compared. A locomotion compensator was used to separately record walking

  3. Pheromone produced by the myxobacterium Stigmatella aurantiaca.

    OpenAIRE

    Stephens, K; Hegeman, G D; White, D

    1982-01-01

    An extracellular, diffusible signaling molecule (pheromone) was produced by Stigmatella aurantiaca during fruiting body formation. The pheromone decreased the aggregation period in both the light and the dark and substituted for light in stimulating the maturation of aggregates into fruiting bodies. The cells were more sensitive to lower concentrations of pheromone in the light than in the dark, possibly explaining the stimulation of aggregation and fruiting body formation by light. The phero...

  4. Olfactory responses of banana weevil predators to volatiles from banana pseudostem tissue and synthetic pheromone.

    Science.gov (United States)

    Tinzaara, W; Gold, C S; Dicke, M; van Huis, A

    2005-07-01

    As a response to attack by herbivores, plants can emit a variety of volatile substances that attract natural enemies of these insect pests. Predators of the banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae) such as Dactylosternum abdominale (Coleoptera: Hydrophilidae) and Pheidole megacephala (Hymenoptera: Formicidae), are normally found in association with weevil-infested rotten pseudostems and harvested stumps. We investigated whether these predators are attracted to such environments in response to volatiles produced by the host plant, by the weevil, or by the weevil plant complex. We evaluated predator responses towards volatiles from banana pseudostem tissue (synomones) and the synthetic banana weevil aggregation pheromone Cosmolure+ in a two-choice olfactometer. The beetle D. abdominale was attracted to fermenting banana pseudostem tissue and Cosmolure+, whereas the ant P. megacephala was attracted only to fermented pseudostem tissue. Both predators were attracted to banana pseudostem tissue that had been damaged by weevil larvae irrespective of weevil presence. Adding pheromone did not enhance predator response to volatiles from pseudostem tissue fed on by weevils. The numbers of both predators recovered with pseudostem traps in the field from banana mats with a pheromone trap were similar to those in pseudostem traps at different distance ranges from the pheromone. Our study shows that the generalist predators D. abdominale and P. megacephala use volatiles from fermented banana pseudostem tissue as the major chemical cue when searching for prey.

  5. 40 CFR 180.1080 - Plant volatiles and pheromone; exemptions from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Plant volatiles and pheromone... RESIDUES IN FOOD Exemptions From Tolerances § 180.1080 Plant volatiles and pheromone; exemptions from the... pheromone Z-2-isopropenyl-1-methylcyclobutaneethanol; Z-3,3-dimethyl-Δ1,β-cyclohexaneethanol; Z-3,3-dimethyl...

  6. 10-Methyldodecanal, a Novel Attractant Pheromone Produced by Males of the South American Cerambycid Beetle Eburodacrys vittata.

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    Weliton D Silva

    Full Text Available We report the identification, synthesis, and field bioassay of a novel attractant pheromone produced by males of Eburodacrys vittata (Blanchard, a South American cerambycid beetle in the subfamily Cerambycinae. Headspace volatiles from males contained a sex-specific compound, identified as 10-methyldodecanal. In a field bioassay conducted in Brazil, significant numbers of males and females were caught in traps baited with synthesized racemic 10-methyldodecanal, consistent with the aggregation-sex pheromones produced by males of many cerambycine species. This compound represents a new structural class of cerambycid pheromones, and it is the first pheromone identified for a species in the tribe Eburiini.

  7. Identification of volatile sex pheromone components released by the southern armyworm,Spodoptera eridania (Cramer).

    Science.gov (United States)

    Teal, P E; Mitchell, E R; Tumlinson, J H; Heath, R R; Sugie, H

    1985-06-01

    Analysis of sex pheromone gland extracts and volatile pheromone components collected from the calling female southern armyworm,Spodoptera eridania (Cramer), by high-resolution capillary gas chromatography and mass spectroscopy indicated that a number of 14-carbon mono- and diunsaturated acetates and a monounsaturated 16-carbon acetate were produced. Gland extracts also indicated the presence of (Z)-9-tetradecen-1-ol. However, this compound was not found in collections of volatiles. Field trapping studies indicated that the volatile blend composed of (Z)-9-tetradecen-1-ol acetate (60%), (Z)-9-(E)-12-tetradecadien-1-ol acetate (17%), (Z)-9-(Z)-12-tetradecadien-1-ol acetate (15%), (Z)-9-(E)-11-tetradecadien-1-ol acetate (5%), and (Z)-11-hexadecen-1-ol acetate (3 %) was an effective trap bait for males of this species. The addition of (Z)-9-tetradecen-1-ol to the acetate blends tested resulted in the capture of beet armyworm,S. exigua (Hubner), males which provides further evidence that the alcohol is a pheromone component of this species.

  8. Non-Host Plant Volatiles Disrupt Sex Pheromone Communication in a Specialist Herbivore

    Science.gov (United States)

    Wang, Fumin; Deng, Jianyu; Schal, Coby; Lou, Yonggen; Zhou, Guoxin; Ye, Bingbing; Yin, Xiaohui; Xu, Zhihong; Shen, Lize

    2016-01-01

    The ecological effects of plant volatiles on herbivores are manifold. Little is known, however, about the impacts of non-host plant volatiles on intersexual pheromonal communication in specialist herbivores. We tested the effects of several prominent constitutive terpenoids released by conifers and Eucalyptus trees on electrophysiological and behavioral responses of an oligophagous species, Plutella xylostella, which feeds on Brassicaceae. The non-host plant volatile terpenoids adversely affected the calling behavior (pheromone emission) of adult females, and the orientation responses of adult males to sex pheromone were also significantly inhibited by these terpenoids in a wind tunnel and in the field. We suggest that disruption of both pheromone emission and orientation to sex pheromone may explain, at least in part, an observed reduction in herbivore attack in polyculture compared with monoculture plantings. We also propose that mating disruption of both male and female moths with non-host plant volatiles may be a promising alternative pest management strategy. PMID:27585907

  9. Non-Host Plant Volatiles Disrupt Sex Pheromone Communication in a Specialist Herbivore.

    Science.gov (United States)

    Wang, Fumin; Deng, Jianyu; Schal, Coby; Lou, Yonggen; Zhou, Guoxin; Ye, Bingbing; Yin, Xiaohui; Xu, Zhihong; Shen, Lize

    2016-09-02

    The ecological effects of plant volatiles on herbivores are manifold. Little is known, however, about the impacts of non-host plant volatiles on intersexual pheromonal communication in specialist herbivores. We tested the effects of several prominent constitutive terpenoids released by conifers and Eucalyptus trees on electrophysiological and behavioral responses of an oligophagous species, Plutella xylostella, which feeds on Brassicaceae. The non-host plant volatile terpenoids adversely affected the calling behavior (pheromone emission) of adult females, and the orientation responses of adult males to sex pheromone were also significantly inhibited by these terpenoids in a wind tunnel and in the field. We suggest that disruption of both pheromone emission and orientation to sex pheromone may explain, at least in part, an observed reduction in herbivore attack in polyculture compared with monoculture plantings. We also propose that mating disruption of both male and female moths with non-host plant volatiles may be a promising alternative pest management strategy.

  10. A Background of a Volatile Plant Compound Alters Neural and Behavioral Responses to the Sex Pheromone Blend in a Moth.

    Science.gov (United States)

    Dupuy, Fabienne; Rouyar, Angéla; Deisig, Nina; Bourgeois, Thomas; Limousin, Denis; Wycke, Marie-Anne; Anton, Sylvia; Renou, Michel

    2017-01-01

    Recognition of intra-specific olfactory signals within a complex environment of plant-related volatiles is crucial for reproduction in male moths. Sex pheromone information is detected by specific olfactory receptor neurons (Phe-ORNs), highly abundant on the male antenna. The information is then transmitted to the pheromone processing macroglomerular complex (MGC) within the primary olfactory center, the antennal lobe, where it is processed by local interneurons and projection neurons. Ultimately a behavioral response, orientation toward the pheromone source, is elicited. Volatile plant compounds (VPCs) are detected by other functional types of olfactory receptor neurons (ORNs) projecting in another area of the antennal lobe. However, Phe-ORNs also respond to some VPCs. Female-produced sex pheromones are emitted within a rich environment of VPCs, some of which have been shown to interfere with the detection and processing of sex pheromone information. As interference between the different odor sources might depend on the spatial and temporal features of the two types of stimuli, we investigated here behavioral and neuronal responses to a brief sex pheromone blend pulse in a VPC background as compared to a control background in the male noctuid moth Agrotis ipsilon . We observed male orientation behavior in a wind tunnel and recorded responses of Phe-ORNs and MGC neurons to a brief sex pheromone pulse within a background of individual VPCs. We also recorded the global input signal to the MGC using in vivo calcium imaging with the same stimulation protocol. We found that VPCs eliciting a response in Phe-ORNs and MGC neurons masked responses to the pheromone and decreased the contrast between background odor and the sex pheromone at both levels, whereas α-pinene did not interfere with first order processing. The calcium signal produced in response to a VPC background was tonic, lasting longer than the VPC stimulus duration, and masked entirely the pheromone response

  11. Interference of plant volatiles on pheromone receptor neurons of male Grapholita molesta (Lepidoptera: Tortricidae).

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    Ammagarahalli, Byrappa; Gemeno, César

    2015-10-01

    In moths, sex pheromone components are detected by pheromone-specific olfactory receptor neurons (ph-ORNs) housed in sensilla trichodea in the male antennae. In Grapholita molesta, ph-ORNs are highly sensitive and specific to the individual sex pheromone components, and thus help in the detection and discrimination of the unique conspecific pheromone blend. Plant odors interspersed with a sub-optimal pheromone dose are reported to increase male moth attraction. To determine if the behavioral synergism of pheromone and plant odors starts at the ph-ORN level, single sensillum recordings were performed on Z8-12:Ac and E8-12:Ac ph-ORNs (Z-ORNs and E-ORNs, respectively) stimulated with pheromone-plant volatile mixtures. First, biologically meaningful plant-volatile doses were determined by recording the response of plant-specific ORNs housed in sensilla auricillica and trichodea to several plant odorants. This exploration provided a first glance at plant ORNs in this species. Then, using these plant volatile doses, we found that the spontaneous activity of ph-ORNs was not affected by the stimulation with plant volatiles, but that a binary mixture of sex pheromone and plant odorants resulted in a small (about 15%), dose-independent, but statistically significant, reduction in the spike frequency of Z-ORNs with respect to stimulation with Z8-12:Ac alone. The response of E-ORNs to a combination of E8-12:Ac and plant volatiles was not different from E8-12:Ac alone. We argue that the small inhibition of Z-ORNs caused by physiologically realistic plant volatile doses is probably not fully responsible for the observed behavioral synergism of pheromone and plant odors. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. E-β-ocimene, a volatile brood pheromone involved in social regulation in the honey bee colony (Apis mellifera.

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    Alban Maisonnasse

    Full Text Available BACKGROUND: In honey bee colony, the brood is able to manipulate and chemically control the workers in order to sustain their own development. A brood ester pheromone produced primarily by old larvae (4 and 5 days old larvae was first identified as acting as a contact pheromone with specific effects on nurses in the colony. More recently a new volatile brood pheromone has been identified: E-β-ocimene, which partially inhibits ovary development in workers. METHODOLOGY AND PRINCIPAL FINDING: Our analysis of E-β-ocimene production revealed that young brood (newly hatched to 3 days old produce the highest quantity of E-β-ocimene relative to their body weight. By testing the potential action of this molecule as a non-specific larval signal, due to its high volatility in the colony, we demonstrated that in the presence of E-β-ocimene nest workers start to forage earlier in life, as seen in the presence of real brood. CONCLUSIONS/SIGNIFICANCE: In this way, young larvae are able to assign precedence to the task of foraging by workers in order to increase food stores for their own development. Thus, in the complexity of honey bee chemical communication, E-β-ocimene, a pheromone of young larvae, provides the brood with the means to express their nutritional needs to the workers.

  13. Male-produced aggregation pheromone of Carpophilus sayi, a nitidulid vector of oak wilt disease, and pheromonal comparison with Carpophilus lugubris

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    Robert J. Bartelt; John F. Kyhl; Angie K. Ambourn; Jennifer Juzwik; Steven J. Seybold

    2004-01-01

    Carpophilus sayi, a nitidulid beetle vector of the oak wilt fungus, Ceratocystis fagacearum, was shown to have a male-produced aggregation pheromone. Six male-specific chemicals were identified from collections of volatiles. The two major compounds were (2E,4E,6E,8E)-3,5-dimethyl-7-ethyl-2,4,6,8- undecatetraene and (2E,4E,6E,8E...

  14. Sex pheromone in the moth Heliothis virescens is produced as a mixture of two pools: de novo and via precursor storage in glycerolipids.

    Science.gov (United States)

    Foster, Stephen P; Anderson, Karin G; Casas, Jérôme

    2017-08-01

    Most species of moths use a female-produced volatile sex pheromone, typically produced via de novo fatty acid synthesis in a specialized gland, for communication among mates. While de novo biosynthesis of pheromone (DNP) is rapid, suggesting transient precursor acids, substantial amounts of pheromone precursor (and other) acids are stored, predominantly in triacylglycerols in the pheromone gland. Whether these stored acids are converted to pheromone later or not has been the subject of some debate. Using a tracer/tracee approach, in which we fed female Heliothis virescens U- 13 C-glucose, we were able to distinguish two pools of pheromone, in which precursors were temporally separated (after and before feeding on labeled glucose): DNP synthesized from a mixed tracer/tracee acetyl CoA pool after feeding, and pheromone made from precursor acids primarily synthesized before feeding, which we call recycled precursor fat pheromone (RPP). DNP titer varied from high (during scotophase) to low (photophase) and with presence/absence of pheromone biosynthesis activating neuropeptide (PBAN), in accord with native pheromone titer previously observed. By contrast, RPP was constant throughout the photoperiod and did not change with PBAN presence/absence. The amount of RPP (6.3-10.3 ng/female) was typically much lower than that of DNP, especially during the scotophase (peak DNP, 105 ng/female). We propose an integral role for stored fats in pheromone biosynthesis, in which they are hydrolyzed and re-esterified throughout the photoperiod, with a small proportion of liberated precursor acyl CoAs being converted to pheromone. During the sexually active period, release of PBAN results in increased flux of glucose (from trehalose) and hydrolyzed acids entering the mitochondria, producing acetyl CoA precursor for de novo fat and pheromone biosynthesis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Non-Host Plant Volatiles Disrupt Sex Pheromone Communication in a Specialist Herbivore

    OpenAIRE

    Wang, Fumin; Deng, Jianyu; Schal, Coby; Lou, Yonggen; Zhou, Guoxin; Ye, Bingbing; Yin, Xiaohui; Xu, Zhihong; Shen, Lize

    2016-01-01

    The ecological effects of plant volatiles on herbivores are manifold. Little is known, however, about the impacts of non-host plant volatiles on intersexual pheromonal communication in specialist herbivores. We tested the effects of several prominent constitutive terpenoids released by conifers and Eucalyptus trees on electrophysiological and behavioral responses of an oligophagous species, Plutella xylostella, which feeds on Brassicaceae. The non-host plant volatile terpenoids adversely affe...

  16. Enhanced attraction of Plutella xylostella (Lepidoptera: Plutellidae) to pheromone-baited traps with the addition of green leaf volatiles.

    Science.gov (United States)

    Li, Pengyan; Zhu, Junwei; Qin, Yuchuan

    2012-08-01

    Diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is one of the most serious pests of Brassicaceae crops worldwide. Electrophysiological and behavioral responses of P. xylostella to green leaf volatiles (GLVs) alone or together with its female sex pheromone were investigated in laboratory and field. GLVs 1-hexanol and (Z)-3-hexen-1-ol elicited strong electroantennographic responses from unmated male and female P. xylostella, whereas (Z)-3-hexenyl acetate only produced a relatively weak response. The behavioral responses of unmated moths to GLVs were further tested in Y-tube olfactometer experiments. (E)-2-Hexenal, (Z)-3-hexen-1-ol, and (Z)-3-hexenyl acetate induced attraction of males, reaching up to 50%, significantly higher than the response to the unbaited control arm. In field experiments conducted in 2008 and 2009, significantly more moths were captured in traps baited with synthetic sex pheromone with either (Z)-3-hexenyl acetate alone or a blend of (Z)-3-hexenyl acetate, (Z)-3-hexen-1-ol, and (E)-2-hexenal compared with sex pheromone alone and other blend mixtures. These results demonstrated that GLVs could be used to enhance the attraction of P. xylostella males to sex pheromone-baited traps.

  17. Effects of bark beetle pheromones on the attraction of Monochamus alternatus to pine volatiles

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    Jian-Ting Fan; Daniel Miller; Long-Wa Zhang; Jiang-Hua Sun

    2010-01-01

    We evaluated the attraction of Monochamus alternatus Hope (Coleoptera: Cerambycidae), Dryocoetes luteus Blandford and Orthotomicus erosusWollaston (Coleoptera: Curculionidae: Scolytinae) to multiple-funnel traps baited with the pine volatiles, ethanol and (+)-α-pinene and the bark beetle pheromones, ipsenol and ipsdienol. M. alternatus were attracted to traps baited...

  18. Presence of Putative Male-Produced Sex Pheromone in Lutzomyia cruciata (Diptera: Psychodidae), Vector of Leishmania mexicana.

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    Serrano, A K; Rojas, J C; Cruz-López, L C; Malo, Edi A; Mikery, O F; Castillo, A

    2016-11-01

    Lutzomyia cruciata (Coquillet) is a vector of cutaneous leishmaniasis in Mexico and Central America. However, several aspects of its ecology and behavior are unknown, including whether a male pheromone partially mediates the sexual behavior of this sand fly. In this study, we evaluated the behavioral response of females to male abdominal extracts in a Y-tube olfactometer. The volatile compounds from male abdominal extracts were identified by gas chromatography-mass spectrometry and compared with those of female abdominal extracts. Finally, the disseminating structures of the putative sex pheromone were examined by scanning electron microscopy in the male abdomen. Females were more attracted to male abdominal extract than to the hexane control, suggesting the presence of male-produced sex pheromone. The male abdominal extracts were characterized by the presence of 12 sesquiterpene compounds. The major component, an unknown sesquiterpene with an abundance of 60%, had a mass spectrum with molecular ion of m/z 262. In contrast, the abdominal female extracts contained saturated fatty acids. Finally, we detected the presence of small "papules" with a mammiform morphology distributed on the abdominal surface of tergites IV-VII of male Lu. cruciata These structures are not present in females. We conclude that Lu. cruciata males likely produce a pheromone involved in attracting or courting females. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Poison and alarm: the Asian hornet Vespa velutina uses sting venom volatiles as an alarm pheromone.

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    Cheng, Ya-Nan; Wen, Ping; Dong, Shi-Hao; Tan, Ken; Nieh, James C

    2017-02-15

    In colonial organisms, alarm pheromones can provide a key fitness advantage by enhancing colony defence and warning of danger. Learning which species use alarm pheromone and the key compounds involved therefore enhances our understanding of how this important signal has evolved. However, our knowledge of alarm pheromones is more limited in the social wasps and hornets compared with the social bees and ants. Vespa velutina is an economically important and widespread hornet predator that attacks honey bees and humans. This species is native to Asia and has now invaded Europe. Despite growing interest in V. velutina , it was unknown whether it possessed an alarm pheromone. We show that these hornets use sting venom as an alarm pheromone. Sting venom volatiles were strongly attractive to hornet workers and triggered attacks. Two major venom fractions, consisting of monoketones and diketones, also elicited attack. We used gas chromatography coupled to electroantennographic detection (GC-EAD) to isolate 13 known and 3 unknown aliphatic ketones and alcohols in venom that elicited conspicuous hornet antennal activity. Two of the unknown compounds may be an undecen-2-one and an undecene-2,10-dinone. Three major compounds (heptan-2-one, nonan-2-one and undecan-2-one) triggered attacks, but only nonan-2-one did so at biologically relevant levels (10 hornet equivalents). Nonan-2-one thus deserves particular attention. However, the key alarm releasers for V. velutina remain to be identified. Such identification will help to illuminate the evolution and function of alarm compounds in hornets. © 2017. Published by The Company of Biologists Ltd.

  20. Attraction of Cerambycid Beetles to Their Aggregation-Sex Pheromones Is Influenced by Volatiles From Host Plants of Their Larvae.

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    Wong, J C H; Zou, Y; Millar, J G; Hanks, L M

    2017-06-01

    Here, we describe a field experiment that tested for attraction of cerambycid beetles to odors from angiosperm hosts, and whether plant volatiles also serve to enhance attraction of beetles to their aggregation-sex pheromones. Traps were baited with a blend of synthesized chemicals that are common pheromone components of species in the subfamilies Cerambycinae and Lamiinae. The source of plant volatiles was chipped wood from trees of three angiosperm species, as well as from one nonhost, gymnosperm species. Bioassays were conducted in wooded areas of east-central Illinois. Traps were baited with the pheromone blend alone, the blend + wood chips from one tree species, wood chips alone, or a solvent control lure. Seven species of cerambycids were significantly attracted to the pheromone blend, with or without wood chips. In two cases, wood chips from angiosperms appeared to enhance attraction to pheromones, whereas they inhibited attraction in another three cases. Pine chips did not strongly influence attraction of any species. Overall, our results suggest that host plant volatiles from wood chips may improve trap catch with synthesized pheromones for some cerambycid species, but the effect is not general, necessitating case-by-case testing to determine how individual target species are affected. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Degradation of pheromone and plant volatile components by a same odorant-degrading enzyme in the cotton leafworm, Spodoptera littoralis.

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    Nicolas Durand

    Full Text Available Odorant-Degrading Enzymes (ODEs are supposed to be involved in the signal inactivation step within the olfactory sensilla of insects by quickly removing odorant molecules from the vicinity of the olfactory receptors. Only three ODEs have been both identified at the molecular level and functionally characterized: two were specialized in the degradation of pheromone compounds and the last one was shown to degrade a plant odorant.Previous work has shown that the antennae of the cotton leafworm Spodoptera littoralis, a worldwide pest of agricultural crops, express numerous candidate ODEs. We focused on an esterase overexpressed in males antennae, namely SlCXE7. We studied its expression patterns and tested its catalytic properties towards three odorants, i.e. the two female sex pheromone components and a green leaf volatile emitted by host plants.SlCXE7 expression was concomitant during development with male responsiveness to odorants and during adult scotophase with the period of male most active sexual behaviour. Furthermore, SlCXE7 transcription could be induced by male exposure to the main pheromone component, suggesting a role of Pheromone-Degrading Enzyme. Interestingly, recombinant SlCXE7 was able to efficiently hydrolyze the pheromone compounds but also the plant volatile, with a higher affinity for the pheromone than for the plant compound. In male antennae, SlCXE7 expression was associated with both long and short sensilla, tuned to sex pheromones or plant odours, respectively. Our results thus suggested that a same ODE could have a dual function depending of it sensillar localisation. Within the pheromone-sensitive sensilla, SlCXE7 may play a role in pheromone signal termination and in reduction of odorant background noise, whereas it could be involved in plant odorant inactivation within the short sensilla.

  2. Behavioural evidence of male volatile pheromones in the sex-role reversed wolf spiders Allocosa brasiliensis and Allocosa alticeps

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    Aisenberg, Anita; Baruffaldi, Luciana; González, Macarena

    2010-01-01

    The use of chemical signals in a sexual context is widespread in the animal kingdom. Most studies in spiders report the use of female pheromones that attract potential sexual partners. Allocosa brasiliensis and Allocosa alticeps are two burrowing wolf spiders that show sex-role reversal. Females locate male burrows and initiate courtship before males perform any detectable visual or vibratory signal. So, females of these species would be detecting chemical or mechanical cues left by males. Our objective was to explore the potential for male pheromones to play a role in mate detection in A. brasiliensis and A. alticeps. We designed two experiments. In Experiment 1, we tested the occurrence of male contact pheromones by evaluating female courtship when exposed to empty burrows constructed by males or females (control). In Experiment 2, we tested the existence of male volatile pheromones by evaluating female behaviour when exposed to artificial burrows connected to tubes containing males, females or empty tubes (control). Our results suggest the occurrence of male volatile pheromones that trigger female courtship in both Allocosa species. The sex-role reversal postulated for these wolf spiders could be driving the consequent reversal in typical pheromone-emitter and detector roles expected for spiders.

  3. Male Sexual Behavior and Pheromone Emission Is Enhanced by Exposure to Guava Fruit Volatiles in Anastrepha fraterculus.

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    Guillermo E Bachmann

    Full Text Available Plant chemicals can affect reproductive strategies of tephritid fruit flies by influencing sex pheromone communication and increasing male mating competitiveness.We explored whether exposure of Anastrepha fraterculus males to guava fruit volatiles and to a synthetic blend of volatile compounds released by this fruit affects the sexual performance of wild and laboratory flies. By means of bioassays and pheromone collection we investigated the mechanism underlying this phenomenon.Guava volatile exposure enhanced male mating success and positively affected male calling behavior and pheromone release in laboratory and wild males. Changes in male behavior appear to be particularly important during the initial phase of the sexual activity period, when most of the mating pairs are formed. Exposure of laboratory males to a subset of guava fruit volatiles enhanced mating success, showing that the response to the fruit might be mimicked artificially.Volatiles of guava seem to influence male mating success through an enhancement of chemical and physical signals related to the communication between sexes. This finding has important implications for the management of this pest species through the Sterile Insect Technique. We discuss the possibility of using artificial blends to improve the sexual competitiveness of sterile males.

  4. Male Sexual Behavior and Pheromone Emission Is Enhanced by Exposure to Guava Fruit Volatiles in Anastrepha fraterculus

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    Bachmann, Guillermo E.; Segura, Diego F.; Devescovi, Francisco; Juárez, M. Laura; Ruiz, M. Josefina; Vera, M. Teresa; Cladera, Jorge L.; Fernández, Patricia C.

    2015-01-01

    Background Plant chemicals can affect reproductive strategies of tephritid fruit flies by influencing sex pheromone communication and increasing male mating competitiveness. Objective and Methodology We explored whether exposure of Anastrepha fraterculus males to guava fruit volatiles and to a synthetic blend of volatile compounds released by this fruit affects the sexual performance of wild and laboratory flies. By means of bioassays and pheromone collection we investigated the mechanism underlying this phenomenon. Results Guava volatile exposure enhanced male mating success and positively affected male calling behavior and pheromone release in laboratory and wild males. Changes in male behavior appear to be particularly important during the initial phase of the sexual activity period, when most of the mating pairs are formed. Exposure of laboratory males to a subset of guava fruit volatiles enhanced mating success, showing that the response to the fruit might be mimicked artificially. Conclusions Volatiles of guava seem to influence male mating success through an enhancement of chemical and physical signals related to the communication between sexes. This finding has important implications for the management of this pest species through the Sterile Insect Technique. We discuss the possibility of using artificial blends to improve the sexual competitiveness of sterile males. PMID:25923584

  5. Olfactory responses of Plutella xylostella natural enemies to host pheromone, larval frass, and green leaf cabbage volatiles.

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    Reddy, G V P; Holopainen, J K; Guerrero, A

    2002-01-01

    The parasitoids Trichogramma chilonis (Hymenoptera: Trichogrammatidae) and Cotesia plutellae (Hymenoptera: Braconidae), and the predator Chrysoperla carnea (Neuroptera: Chrysopidae), are potential biological control agents for the diamondback moth, Plutella xylostella (Lepidoptera: Yponomeutidae). We present studies on the interactions between these bioagents and various host-associated volatiles using a Y olfactometer. T chilonis was attracted to a synthetic pheromone blend (Z11-16:Ald, Z11-16:Ac, and Z11-16:OH in a 1:1:0.01 ratio), to Z11-16:Ac alone, and to a 1:1 blend of Z11-16:Ac and Z11-16:Ald. C. plutellae responded to the blend and to Z11-16:Ac and Z11-16:Ald. Male and female C. carnea responded to the blend and to a 1:1 blend of the major components of the pheromone, although no response was elicited by single compounds. Among the four host larval frass volatiles tested (dipropyl disulfide, dimethyl disulfide, allyl isothiocyanate, and dimethyl trisulfide), only allyl isothiocyanate elicited significant responses in the parasitoids and predator, but C. plutellae and both sexes of C. carnea did respond to all four volatiles. Among the green leaf volatiles of cabbage (Brassica oleracea subsp. capitata), only Z3-6:Ac elicited significant responses from T. chilonis, C. plutellae, and C. carnea, but C. plutellae also responded to E2-6:Ald and Z3-6:OH. When these volatiles were blended with the pheromone, the responses were similar to those elicited by the pheromone alone, except for C. carnea males, which had an increased response. The effect of temperature on the response of the biological agents to a mixture of the pheromone blend and Z3-6:Ac was also studied. T. chilonis was attracted at temperatures of 25-35 degrees C, while C. plutellae and C. carnea responded optimally at 30-35 degrees C and 20-25 degrees C, respectively. These results indicate that the sex pheromone and larval frass volatiles from the diamondback moth, as well as volatile compounds from

  6. A study of the female produced sex pheromone of Tenebrio molitor (Coleoptera: Tenebrionidae)

    Science.gov (United States)

    Mangat, Jaswinder

    Mating behaviour in the yellow mealworm beetle, Tenebrio molitor , is mediated by several pheromones, including the female-produced 4-methylnonanol (4-MNol). Mating causes a decline in the titre of 4-MNol. The overall goal of this study was to determine the biochemical mechanism(s) responsible for this decline: i.e., whether the decline was due to an inhibition of pheromone biosynthesis and/or a stimulation of pheromone degradation; whether the decline was caused by the physical effect of mating or was due to the transfer of a factor from the male; and to conduct a preliminary investigation of the regulatory and signal transduction mechanisms involved in the regulation of 4-MNol production. In vitro radioassays for 4-MNol biosynthesis and degradation were developed and used to compare the levels of 4-MNol biosynthesis and degradation in virgin and mated females. Mating caused an inhibition of 4-MNol biosynthesis within 2 hours, but did not affect the rate of pheromone degradation. Decapitation of virgin females caused an inhibition of pheromone biosynthesis and did not prevent the inhibitory effect of mating. The inhibitory effect of mating was mimicked in females that were artificially inseminated with male reproductive tract homogenates (MRTH), but not in females similarly "inseminated" with water, saline, or air. Furthermore, 4-MNol biosynthesis could be inhibited in vitro by the addition of MRTH. These findings indicate that the male transferred one or more pheromonostatic factor(s) to the female during copulation that acted directly on the pheromone-producing tissue (the ovaries). In order to investigate the biochemical basis for the inhibition of pheromone biosynthesis after mating, the role of calcium was determined by modulating the level of calcium (using a calcium chelator, an ionophore, and calcium). However, due to the precipitation of calcium with the phosphate present in the buffer solution, we were unable to determine the role of calcium in the

  7. Orientation of boll weevil,Anthonomus grandis boh. (Coleoptera: Curculionidae), to pheromone and volatile host compound in the laboratory.

    Science.gov (United States)

    Dickens, J C

    1986-01-01

    Behavioral responses of male and female boll weevils to the aggregation pheromone, grandlure, and the major volatile of cotton, β-bisabolol, were investigated using a new dual-choice olfactometer. Dosage-response experiments revealed both males and females to be attracted by the aggregation pheromone at the 1.0 μg dosage. However, only males were attracted to β-bisabolol (1.0 μg). Both sexes were repelled by the highest dosage ofβ-bisabolol tested (10 μg). In preference experiment, males chose grandlure over β-bisabolol, while both sexes chose the combination of grandlure + β-bisabolol over β-bisabolol alone. There was some evidence for synergism between pheromone and plant odor for the females. The results correlate well with previous electrophysiological and behavioral experiments.

  8. Combining 1,4-dimethoxybenzene, the major flower volatile of wild strawberry Fragaria vesca, with the aggregation pheromone of the strawberry blossom weevil Anthonomus rubi improves attraction

    DEFF Research Database (Denmark)

    Wibe, Atle; Borg-Karlson, Anna Karin; Cross, Jerry

    2014-01-01

    The aggregation pheromone of strawberry blossom weevil [Anthonomus rubi Herbst (Col.: Curculionidae)], a 1:4:1 blend of Grandlure I, II and racemic lavadulol, has been available for pest monitoring for several years but shows low attractancy. Attempts to control A.rubi using the pheromone alone...... were also unsuccessful. This paper reports the finding that addition of the major flower volatile from wild strawberry flowers [Fragaria vesca L. (Rosaceae)], 1,4-dimethoxybenzene (comprising 98% of the volatiles emitted from wild strawberry flowers), to the aggregation pheromone increased trap catches...... pest of strawberry....

  9. Pheromones and exocrine glands in Isoptera.

    Science.gov (United States)

    Costa-Leonardo, Ana Maria; Haifig, Ives

    2010-01-01

    Termites are eusocial insects that have a peculiar and intriguing system of communication using pheromones. The termite pheromones are composed of a blend of chemical substances and they coordinate different social interactions or activities, including foraging, building, mating, defense, and nestmate recognition. Some of these sociochemicals are volatile, spreading in the air, and others are contact pheromones, which are transmitted by trophallaxis and grooming. Among the termite semiochemicals, the most known are alarm, trail, sex pheromones, and hydrocarbons responsible for the recognition of nestmates. The sources of the pheromones are exocrine glands located all over the termite body. The principal exocrine structures considered pheromone-producing glands in Isoptera are the frontal, mandibular, salivary or labial, sternal, and tergal glands. The frontal gland is the source of alarm pheromone and defensive chemicals, but the mandibular secretions have been little studied and their function is not well established in Isoptera. The secretion of salivary glands involves numerous chemical compounds, some of them without pheromonal function. The worker saliva contains a phagostimulating pheromone and probably a building pheromone, while the salivary reservoir of some soldiers contains defensive chemicals. The sternal gland is the only source of trail-following pheromone, whereas sex pheromones are secreted by two glandular sources, the sternal and tergal glands. To date, the termite semiochemicals have indicated that few molecules are involved in their chemical communication, that is, the same compound may be secreted by different glands, different castes and species, and for different functions, depending on the concentration. In addition to the pheromonal parsimony, recent studies also indicate the occurrence of a synergic effect among the compounds involved in the chemical communication of Isoptera. Copyright © 2010 Elsevier Inc. All rights reserved.

  10. Multi-functional roles of a soldier-specific volatile as a worker arrestant, primer pheromone and an antimicrobial agent in a termite.

    Science.gov (United States)

    Mitaka, Yuki; Mori, Naoki; Matsuura, Kenji

    2017-07-26

    Division of labour in eusocial insects is characterized by efficient communication systems based on pheromones. Among such insects, termites have evolved specialized sterile defenders, called soldiers. Because they are incapable of feeding themselves, it has been suggested that soldiers are sustained by workers and emit the pheromone arresting workers. However, such a soldier pheromone has not been identified in any termite species, and the details of the soldier-worker interaction remain to be explored. Here, we identified a soldier-specific volatile sesquiterpene as a worker arrestant, which also acts as a primer pheromone regulating soldier differentiation and fungistatic agent in a termite Reticulitermes speratus Chemical analyses revealed that (-)- β -elemene is the major component of soldier extract, and its authentic standard exhibited arrestant activity to workers and inhibited the differentiation from workers to soldiers. This compound also showed fungistatic activity against entomopathogenic fungi. These suggest that (-)- β -elemene secreted by soldiers acts not only as a worker arrestant but also as one component of inhibitory primer pheromone and an anti-pathogenic agent. Our study provides novel evidence supporting the multi-functionality of termite soldier pheromone and provides new insights into the role of soldiers and the evolutionary mechanisms of pheromone compounds. © 2017 The Author(s).

  11. Role of solid-phase microextraction in the identification of highly volatile pheromones of two Rhinoceros beetles Scapanes australis and Strategus aloeus (Coleoptera, Scarabaeidae, Dynastinae).

    Science.gov (United States)

    Rochat, D; Ramirez-Lucas, P; Malosse, C; Aldana, R; Kakul, T; Morin, J P

    2000-07-14

    Solid-phase microextraction (SPME) samplings from live insects or natural secretion allowed one to identify the aggregation pheromones of the pest beetles Scapanes australis and Strategus aloeus by efficient and rapid isolation of their highly volatile (72 < M(r) < 116) components. S. australis male pheromone was identified as a 84:12:4 (w/w) mixture of 2-butanol [67:33 (R)-(-):(S)-(+) ratio], 3-hydroxy-2-butanone and 2,3-butanediol [43:17:40 (R,R)-(-):(S,S)-(+):meso ratio], and S. aloeus pheromone as a 95.5:4.0:0.5 (w/w) mixture of 2-butanone, 3-pentanone and sec.-butyl acetate by GC-MS using conventional and chiral capillary columns. This is the first report of Scarabaeidae pheromones based on such small and common molecules.

  12. Olfactory receptor neuron responses of a longhorned beetle, Tetropium fuscum (Fabr.) (Coleoptera: Cerambycidae), to pheromone, host, and non-host volatiles.

    Science.gov (United States)

    MacKay, Colin A; Sweeney, Jon D; Hillier, N Kirk

    2015-12-01

    Longhorn wood-boring beetles (Coleoptera: Cerambycidae) use olfactory cues to find mates and hosts for oviposition. Tetropium fuscum (Fabr.) is an invasive longhorned wood-boring beetle originating from Europe that has been established in Nova Scotia, Canada, since at least 1990. This study used single sensillum recordings (SSR) to determine the response of olfactory receptor neurons (ORNs) in the antennal sensilla of male and female T. fuscum to different kinds of olfactory cues, namely host volatiles, non-host volatiles, the aggregation pheromone of T. fuscum (fuscumol), and an aggregation pheromone emitted by other species of longhorn beetles (3-hydroxyhexan-2-one). Each compound had been previously shown to elicit antennal activity in T. fuscum using electroantennography or had been shown to elicit behavioral activity in T. fuscum or other cerambycids. There have been very few SSR studies done on cerambycids, and ours is the first to compare response profiles of pheromone components as well as host and non-host volatiles. Based on SSR studies with other insects, we predicted we would find ORNs that responded to the pheromone alone (pheromone-specialists), as well as ORNs that responded only to host or non-host volatiles, i.e., separation of olfactory cue perception at the ORN level. Also, because male T. fuscum emerge earlier than females and are the pheromone-emitting sex, we predicted that the number of pheromone-sensitive ORNs would be greater in females than males. We found 140 ORNs housed within 97 sensilla that responded to at least one of the 13 compounds. Fuscumol-specific ORNs made up 15% (21/140) of all recordings, but contrary to our prediction, an additional 22 ORNs (16%) responded to fuscumol plus at least one other compound; in total, fuscumol elicited a response from 43/140 (31%) of ORNs with fuscumol-specific ORNs accounting for half of these. Thus, our prediction that pheromone reception would be segregated on specialist ORNs was only partially

  13. Novel, male-produced aggregation pheromone of the cerambycid beetle Rosalia alpina, a priority species of European conservation concern

    Czech Academy of Sciences Publication Activity Database

    Žunič Kosi, A.; Zou, Y.; Hoskovec, Michal; Vrezec, A.; Stritih, N.; Millar, J. G.

    2017-01-01

    Roč. 12, č. 8 (2017), č. článku e0183279. E-ISSN 1932-6203 Institutional support: RVO:61388963 Keywords : 1758 Coleoptera Cerambycidae * host plant volatiles * sex pheromone Subject RIV: CC - Organic Chemistry OBOR OECD: Organic chemistry Impact factor: 2.806, year: 2016 http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0183279

  14. Reverse chemical ecology: Olfactory proteins from the giant panda and their interactions with putative pheromones and bamboo volatiles.

    Science.gov (United States)

    Zhu, Jiao; Arena, Simona; Spinelli, Silvia; Liu, Dingzhen; Zhang, Guiquan; Wei, Rongping; Cambillau, Christian; Scaloni, Andrea; Wang, Guirong; Pelosi, Paolo

    2017-11-14

    The giant panda Ailuropoda melanoleuca belongs to the family of Ursidae; however, it is not carnivorous, feeding almost exclusively on bamboo. Being equipped with a typical carnivorous digestive apparatus, the giant panda cannot get enough energy for an active life and spends most of its time digesting food or sleeping. Feeding and mating are both regulated by odors and pheromones; therefore, a better knowledge of olfaction at the molecular level can help in designing strategies for the conservation of this species. In this context, we have identified the odorant-binding protein (OBP) repertoire of the giant panda and mapped the protein expression in nasal mucus and saliva through proteomics. Four OBPs have been identified in nasal mucus, while the other two were not detected in the samples examined. In particular, AimelOBP3 is similar to a subset of OBPs reported as pheromone carriers in the urine of rodents, saliva of the boar, and seminal fluid of the rabbit. We expressed this protein, mapped its binding specificity, and determined its crystal structure. Structural data guided the design and preparation of three protein mutants bearing single-amino acid replacements in the ligand-binding pocket, for which the corresponding binding affinity spectra were measured. We also expressed AimelOBP5, which is markedly different from AimelOBP3 and complementary in its binding spectrum. By comparing our binding data with the structures of bamboo volatiles and those of typical mammalian pheromones, we formulate hypotheses on which may be the most relevant semiochemicals for the giant panda.

  15. Antenna-predominant and male-biased CSP19 of Sesamia inferens is able to bind the female sex pheromones and host plant volatiles.

    Science.gov (United States)

    Zhang, Ya-Nan; Ye, Zhan-Feng; Yang, Ke; Dong, Shuang-Lin

    2014-02-25

    Insect chemosensory proteins (CSPs) are proposed to capture and transport hydrophobic chemicals across the sensillum lymph to olfactory receptors (ORs), but this has not been clarified in moths. In this study, we built on our previously reported segment sequence work and cloned the full length CSP19 gene (SinfCSP19) from the antennae of Sesamia inferens by using rapid amplification of cDNA ends. Quantitative real time-PCR (qPCR) assays indicated that the gene was expressed in a unique profile, i.e. predominant in antennae and significantly higher in male than in female. To explore the function, recombinant SinfCSP19 was expressed in Escherichia coli cells and purified by Ni-ion affinity chromatography. Binding affinities of the recombinant SinfCSP19 with 39 plant volatiles, 3 sex pheromone components and 10 pheromone analogs were measured using fluorescent competitive binding assays. The results showed that 6 plant volatiles displayed high binding affinities to SinfCSP19 (Ki = 2.12-8.75 μM), and more interesting, the 3 sex pheromone components and analogs showed even higher binding to SinfCSP19 (Ki = 0.49-1.78 μM). Those results suggest that SinfCSP19 plays a role in reception of female sex pheromones of S. inferens and host plant volatiles. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Range of Attraction of Pheromone Lures and Dispersal Behavior of Cerambycid Beetles

    Science.gov (United States)

    E. Dunn; J. Hough-Goldstein; L. M. Hanks; J. G. Millar; V. D' Amico

    2016-01-01

    Cerambycid beetles (Coleoptera: Cerambycidae) can locate suitable hosts and mates by sensing pheromones and plant volatiles. Many cerambycid pheromone components have been identified and are now produced synthetically for trap lures. The range over which these lures attract cerambycids within a forest, and the tendency for cerambycids to move out of a forest in...

  17. Gamma radiation effects on the structure of the sex pheromone producing gland in the female Trogoderma Granarium Everts

    International Nuclear Information System (INIS)

    Gharib, O.H.; Elnaggar, S.E.M.; Abdelkawy, F.K.

    1993-01-01

    Effect of gamma irradiation on the structure of the sex pheromone producing gland in 2-day-old females, Trogoderma Granarium Everts was investigated. With the sub sterilizing doses 20 and 40 Gray, the structure started to be destroyed and became undistinguished as well as the sterilizing dose 60 Gray caused complete damage and the glandular tissue appeared as a narrow ribbon. 4 fig

  18. Can producer currency pricing models generate volatile real exchange rates?

    OpenAIRE

    Povoledo, L.

    2012-01-01

    If the elasticities of substitution between traded and nontraded and between Home and Foreign traded goods are sufficiently low, then the real exchange rate generated by a model with full producer currency pricing is as volatile as in the data.

  19. HONEY BEE COLONY PHEROMONES

    Directory of Open Access Journals (Sweden)

    M Dražić

    2001-09-01

    Full Text Available ABSTRACT Pheromones are chemicals produced as liquids by specialised cells or glands and transmitted into the environment as liquids or gases. In contrary to hormones, which are excreted in organism and have effect exclusively on organism that produced them, pheromones are excreted outside organism and effect on different individuals of the same species. Pheromones mediate nearly all aspects of honeybee colony life including social defence, brood care, mating, orientation, foraging and reproduction. Pheromone investigation has high economic importance. With use of pheromones it is possible to manipulate with pest insects on crops or to direct honeybees during pollination on target plants.

  20. Olfactory responses of banana weevil predators to volatiles from banana pseudostem tissue and synthetic pheromone

    NARCIS (Netherlands)

    Tinzaara, W.; Gold, C.S.; Dicke, M.; Huis, van A.

    2005-01-01

    As a response to attack by herbivores, plants can emit a variety of volatile substances that attract natural enemies of these insect pests. Predators of the banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae) such as Dactylosternum abdominale (Coleoptera: Hydrophilidae) and

  1. Multiple length peptide-pheromone variants produced by Streptococcus pyogenes directly bind Rgg proteins to confer transcriptional regulation.

    Science.gov (United States)

    Aggarwal, Chaitanya; Jimenez, Juan Cristobal; Nanavati, Dhaval; Federle, Michael J

    2014-08-08

    Streptococcus pyogenes, a human-restricted pathogen, accounts for substantial mortality related to infections worldwide. Recent studies indicate that streptococci produce and respond to several secreted peptide signaling molecules (pheromones), including those known as short hydrophobic peptides (SHPs), to regulate gene expression by a quorum-sensing mechanism. Upon transport into the bacterial cell, pheromones bind to and modulate activity of receptor proteins belonging to the Rgg family of transcription factors. Previously, we reported biofilm regulation by the Rgg2/3 quorum-sensing circuit in S. pyogenes. The aim of this study was to identify the composition of mature pheromones from cell-free culture supernatants that facilitate biofilm formation. Bioluminescent reporters were employed to detect active pheromones in culture supernatants fractionated by reverse-phase chromatography, and mass spectrometry was used to characterize their properties. Surprisingly, multiple SHPs that varied by length were detected. Synthetic peptides of each variant were tested individually using bioluminescence reporters and biofilm growth assays, and although activities differed widely among the group, peptides comprising the C-terminal eight amino acids of the full-length native peptide were most active. Direct Rgg/SHP interactions were determined using a fluorescence polarization assay that utilized FITC-labeled peptide ligands. Peptide receptor affinities were seen to be as low as 500 nm and their binding affinities directly correlated with observed bioactivity. Revelation of naturally produced pheromones along with determination of their affinity for cognate receptors are important steps forward in designing compounds whose purpose is positioned for future therapeutics aimed at treating infections through the interference of bacterial communication. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. Cerambycid Beetle Species with Similar Pheromones are Segregated by Phenology and Minor Pheromone Components.

    Science.gov (United States)

    Mitchell, Robert F; Reagel, Peter F; Wong, Joseph C H; Meier, Linnea R; Silva, Weliton Dias; Mongold-Diers, Judith; Millar, Jocelyn G; Hanks, Lawrence M

    2015-05-01

    Recent research has shown that volatile sex and aggregation-sex pheromones of many species of cerambycid beetles are highly conserved, with sympatric and synchronic species that are closely related (i.e., congeners), and even more distantly related (different subfamilies), using the same or similar pheromones. Here, we investigated mechanisms by which cross attraction is averted among seven cerambycid species that are native to eastern North America and active as adults in spring: Anelaphus pumilus (Newman), Cyrtophorus verrucosus (Olivier), Euderces pini (Olivier), Neoclytus caprea (Say), and the congeners Phymatodes aereus (Newman), P. amoenus (Say), and P. varius (F.). Males of these species produce (R)-3-hydroxyhexan-2-one as their dominant or sole pheromone component. Our field bioassays support the hypothesis that cross attraction between species is averted or at least minimized by differences among species in seasonal phenology and circadian flight periods of adults, and/or by minor pheromone components that act as synergists for conspecifics and antagonists for heterospecifics.

  3. Spatial displacement of release point can enhance activity of an attractant pheromone synergist of a bark beetle.

    Science.gov (United States)

    Brian Sullivan; Kenji Mori

    2009-01-01

    Flight responses of the southern pine beetle, Dendroctonus frontalis Zimmermann, to widely-spaced (>130 m) traps baited with pine volatiles (in turpentine) and the female-produced pheromone component frontalin were enhanced when a bait containing the male pheromone component (+)-endo-brevicomin was attached...

  4. Blends of Pheromones, With and Without Host Plant Volatiles, Can Attract Multiple Species of Cerambycid Beetles Simultaneously

    Science.gov (United States)

    L.M. Hanks; J.A. Mongold-Diers; T.H. Atkinson; M.K. Fierke; M.D. Ginzel; E.E. Graham; T.M. Poland; A.B. Richards; M.L. Richardson; J.G. Millar

    2018-01-01

    Pheromone components of cerambycid beetles are often conserved, with a given compound serving as a pheromone component for multiple related species, including species native to different continents. Consequently, a single synthesized compound may attract multiple species to a trap simultaneously. Furthermore, our previous research in east-central Illinois had...

  5. Marine Vibrio Species Produce the Volatile Organic Compound Acetone

    OpenAIRE

    Nemecek-Marshall, M.; Wojciechowski, C.; Kuzma, J.; Silver, G. M.; Fall, R.

    1995-01-01

    While screening aerobic, heterotrophic marine bacteria for production of volatile organic compounds, we found that a group of isolates produced substantial amounts of acetone. Acetone production was confirmed by gas chromatography, gas chromatography-mass spectrometry, and high-performance liquid chromatography. The major acetone producers were identified as nonclinical Vibrio species. Acetone production was maximal in the stationary phase of growth and was stimulated by addition of l-leucine...

  6. Current perspectives on the volatile-producing fungal endophytes.

    Science.gov (United States)

    Zhi-Lin, Yuan; Yi-Cun, Chen; Bai-Ge, Xu; Chu-Long, Zhang

    2012-12-01

    Microbial-derived volatiles are ubiquitous in the environment and actively engaged in bio-communication with other organisms. Recently, some volatile-producing endophytes (VPEs), cryptic fungal symbionts persisting in healthy plant tissues, have attracted great attention due to their strong antibiotic activity or production of carbon chains that are identical to many of those found in petroleum, while other fragrant volatiles can be used in the flavoring industries. From an application-oriented and biotechnological point of view, these findings show significant promise for sustainable development of agriculture, forestry, and industry, especially in the control of fruit postharvest diseases, soil-borne pathogen management, and bio-fuel production. In comparison, the ecological importance of VPEs has only rarely been addressed and warrants further exploration. In this review, we summarize the current knowledge and future directions in this fascinating research field, and also highlight the constraints and progresses towards commercialization of VPEs products.

  7. Queen pheromones

    Science.gov (United States)

    2010-01-01

    Group-living species produce signals that alter the behavior and even the physiology of their social partners. Social insects possess especially sophisticated chemical communication systems that govern every aspect of colony life, including the defining feature of eusociality: reproductive division of labor. Current evidence hints at the central importance of queen pheromones, but progress has been hindered by the fact that such pheromones have only been isolated in honeybees. In a pair of papers on the ant Lasius niger, we identified and investigated a queen pheromone regulating worker sterility. The cuticular hydrocarbon 3-methylhentriacontane (3-MeC31) is correlated with queen maturity and fecundity and workers are also more likely to execute surplus queens that have low amounts of this chemical. Experiments with synthetic 3-MeC31 found that it inhibits ovarian development in queenless workers and lowers worker aggression towards objects coated with it. Production of 3-MeC31 by queens was depressed by an experimental immune challenge, and the same chemical was abundant on queenlaid eggs, suggesting that the workers' responses to the queen are conditional on her health and fecundity. Together with other studies, these results indicate that queen pheromones are honest signals of quality that simultaneously regulate multiple social behaviors. PMID:21331238

  8. Stylopsal: The First Identified Female-produced Sex Pheromone of Strepsiptera

    Czech Academy of Sciences Publication Activity Database

    Cvačka, Josef; Jiroš, Pavel; Kalinová, Blanka; Straka, J.; Černá, K.; Šebesta, Petr; Tomčala, Aleš; Vašíčková, Soňa; Jahn, Ullrich; Šobotník, Jan

    2012-01-01

    Roč. 38, č. 12 (2012), s. 1483-1491 ISSN 0098-0331 R&D Projects: GA ČR GAP506/10/1466 Institutional support: RVO:61388963 Keywords : strepsiptera * stylops * sex pheromone * aldehyde * trimethyldodecanal * fat body Subject RIV: CC - Organic Chemistry Impact factor: 2.462, year: 2012

  9. Process for producing volatile hydrocarbons from hydrocarbonaceous solids

    Energy Technology Data Exchange (ETDEWEB)

    1949-02-03

    In a process for producing volatile hydrocarbons from hydrocarbonaceous solids, a hydrocarbonaceus solid is passed in subdivided state and in the form of a bed downwardly through an externally unheated distilling retort wherein the evolution of volatiles from the bed is effected while solid material comprising combustible heavy residue is discharged from the lower portion of the bed and retort, combustibles are burned from the discharged solid material. The admixture resultant combustion gases with the vapours evolved in the retort is prevented, and a stream of hydrocarbon fluid is heated by indirect heat exchange with hot combustion gases produced by burning to a high temperature and is introduced into the distilling retort and direct contact with bed, supplying heat to the latter for effecting the evolution of volatiles from the hydrocarbonaceous solid. The improvement consists of subjecting the volatile distillation products evolved and removed from the bed to a fractionation and separating selected relatively light and heavy hydrocarbon fractions from the distillation products, withdrawing at least one of the selected fractions from the prcess as a product heating at least one other of the selected fractions to high temperature by the indirect heat exchange with hot combustion gases, and introducing the thus heated hydrocarbon fraction into direct contact with the bed.

  10. Streptopyridines, volatile pyridine alkaloids produced by Streptomyces sp. FORM5

    Directory of Open Access Journals (Sweden)

    Ulrike Groenhagen

    2014-06-01

    Full Text Available Streptomyces sp. FORM5 is a bacterium that is known to produce the antibiotic streptazolin and related compounds. We investigated the strain for the production of volatiles using the CLSA (closed-loop stripping analysis method. Liquid and agar plate cultures revealed the formation of new 2-alkylpyridines (streptopyridines, structurally closely related to the already known 2-pentadienylpiperidines. The structures of the streptopyridines A to E were confirmed by total synthesis. The analysis of the liquid phase by solvent extraction or extraction with an Oasis adsorbent showed that streptazolin and 2-pentadienylpiperidine are the major compounds, while the streptopyridines are only minor components. In the gas phase, only the streptopyridines could be detected. Therefore, an orthogonal set of analysis is needed to assess the metabolic profile of bacteria, because volatile compounds are obviously overlooked by traditional analytical methods. The streptopyridines are strain specific volatiles that are accompanied by a broad range of headspace constituents that occur in many actinomycetes. Volatiles might be of ecological importance for the producing organism, and, as biosynthetic intermediates or shunt products, they can be useful as indicators of antibiotic production in a bacterium.

  11. Transgenic plants producing the bacterial pheromone N-acyl-homoserine lactone exhibit enhanced resistance to the bacterial phytopathogen Erwinia carotovora.

    Science.gov (United States)

    Mäe, A; Montesano, M; Koiv, V; Palva, E T

    2001-09-01

    Bacterial pheromones, mainly different homoserine lactones, are central to a number of bacterial signaling processes, including those involved in plant pathogenicity. We previously demonstrated that N-oxoacyl-homoserine lactone (OHL) is essential for quorum sensing in the soft-rot phytopathogen Erwinia carotovora. In this pathogen, OHL controls the coordinate activation of genes encoding the main virulence determinants, extracellular plant cell wall degrading enzymes (PCWDEs), in a cell density-dependent manner. We suggest that E. carotovora employ quorum sensing to avoid the premature production of PCWDEs and subsequent activation of plant defense responses. To test whether modulating this sensory system would affect the outcome of a plant-pathogen interaction, we generated transgenic tobacco, producing OHL. This was accomplished by ectopic expression in tobacco of the E. carotovora gene expI, which is responsible for OHL biosynthesis. We show that expI-positive transgenic tobacco lines produced the active pheromone and partially complemented the avirulent phenotype of expI mutants. The OHL-producing tobacco lines exhibited enhanced resistance to infection by wild-type E. carotovora. The results were confirmed by exogenous addition of OHL to wild-type plants, which also resulted in increased resistance to E. carotovora.

  12. Pheromone Signalling

    Science.gov (United States)

    Hart, Adam G.

    2011-01-01

    Pheromones are chemicals used to communicate with members of the same species. First described in insects, pheromones are often used to attract mates but in social insects, such as ants and bees, pheromone use is much more sophisticated. For example, ants use pheromones to make foraging trails and the chemical and physical properties of the…

  13. Three odorant binding proteins may regulate the behavioural response of Chrysopa pallens to plant volatiles and the aphid alarm pheromone (E)-β-farnesene.

    Science.gov (United States)

    Li, Z-Q; Zhang, S; Cai, X-M; Luo, J-Y; Dong, S-L; Cui, J-J; Chen, Z-M

    2017-06-01

    Artificial Chrysopa pallens release is a well-known method for suppressing aphids, but it is difficult to establish lacewing populations in the field. Understanding the functions of C. pallens odorant-binding proteins (CpalOBPs) and behavioural responses of C. pallens to plant volatiles and aphid alarm pheromone (E)-ß-farnesene has important implications for population establishment after lacewing release. Based on our previous study, five antennae-enriched CpalOBPs were selected. Sequence alignment and phylogenetic analysis revealed that these five CpalOBPs were Classic OBPs and separated into different clades. Of them, CpalOBP10 clustered in the same clade with aphid OBP7, which mediates the perception of green leaf volatiles and (E)-ß-farnesene. Ligand-binding assays showed 31 compounds, including plant-derived compounds, pest-induced volatiles and (E)-ß-farnesene, had high binding affinities for at least one of these five CpalOBPs. Of the 31 compounds, the pest-induced volatiles (Z)-3-hexenyl hexanoate and 2-hexyl-1-decanol, used in host location by the black bean aphid, elicited significant attractive behavioural responses from C. pallens. Conversely, (E)-ß-farnesene elicited strongly repellent behavioural responses. It is conceivable that C. pallens utilizes plant-derived compounds, pest-induced volatiles and (E)-ß-farnesene as foraging cues. Our studies provide new insights into the interrelationships amongst C. pallens, its prey and the host plants. Compounds that elicited significant behavioural responses from C. pallens were also identified. © 2017 The Royal Entomological Society.

  14. Financial instruments help producers hedge gas deals in volatile market

    International Nuclear Information System (INIS)

    Lawnin, J.N.; Kupiec, S.L.

    1993-01-01

    The Natural Gas Policy Act (NGPA) of 1978 and more recently the U.S. Federal Energy Regulatory Commission's Order 636 have changed gas marketing from a totally regulated industry to one that responds to free-market forces. The stable but controlled market in which producers once sold gas has become highly competitive and more efficient. Consequently, prices have become more volatile; they respond more quickly than they did before to changes in supply of and demand for natural gas. Prior to deregulation of the natural gas industry, producers had fewer marketing options than they do today. Under a typical gas sales contract, producers sold gas to the nearest pipeline at regulated prices, which remained relatively stable along the interstate distribution chain. The system, however, failed to generate adequate supply of gas. In an effort to realign supply and demand, Congress initiated the deregulation of natural gas with NGPA, which phased out most wellhead price controls. A series of FERC actions culminating in Order 636 extended the process. Now, independent producers can sell gas directly to end users. Under Order 636, interstate pipelines no longer offer merchant services to gas customers. The paper discusses the change in risk profiles, price protection, futures and options, hedged exposure, setting price floors, off-exchange contracts, risk considerations, types of risks, business controls, back office controls, and credit monitoring

  15. Identification of the female-produced sex pheromone of the leafminer Holocacista capensis infesting grapevine in South Africa

    NARCIS (Netherlands)

    Wang, H.-L.; Geertsema, H.; Nieukerken, van E.J.; Löfstedt, C.

    2015-01-01

    We report the first identification of a sex pheromone in a heliozelid moth, Holocacista capensis van Nieukerken & Geertsema. This leafminer recently infested grapevine in South Africa. Compared to solvent extraction of pheromone glands, solid phase microextraction (SPME) proved to be highly

  16. Volatiles produced by the mycophagous soil bacterium Collimonas

    NARCIS (Netherlands)

    Garbeva, P.; Hordijk, C.; Gerards, S.; Boer, de W.

    2014-01-01

    It is increasingly recognized that volatile organic compounds play an import role during interactions between soil microorganisms. Here, we examined the possible involvement of volatiles in the interaction of Collimonas bacteria with soil fungi. The genus Collimonas is known for its ability to grow

  17. Determination of volatiles produced during radiation processing in Laurus cinnamomum

    Energy Technology Data Exchange (ETDEWEB)

    Salum, D.C.; Araujo, M.M.; Fanaro, G.B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Cidade Universitaria, Av. Professor Lineu Prestes 2242, Zip code: 05508-000 Butanta, Sao Paulo, SP (Brazil); Purgatto, E. [Faculdade de Ciencias Farmaceuticas, FCF/USP, Departamento de Alimentos e Nutricao Experimental. Av. Prof. Lineu Prestes, 580 Bloco 14. CEP: 05508-900 Sao Paulo, SP (Brazil)], E-mail: epurgatt@usp.br; Villavicencio, A.L.C.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Cidade Universitaria, Av. Professor Lineu Prestes 2242, Zip code: 05508-000 Butanta, Sao Paulo, SP (Brazil)], E-mail: villavic@ipen.br

    2009-07-15

    In order to protect food from pathogenic microorganisms as well as increase its shelf-life, while keeping sensorial properties (e.g., odor and taste), which are important properties required by spice buyers, it is necessary to analyze volatile formation from irradiation of medicinal and food herbs. Possible changes in the odor of these herbs are evaluated by characterizing different radiation doses and effects on sensorial properties, in order to allow better application of the irradiation technology. The aim of the present study was to analyze volatile formation on cinnamon (Laurus cinnamomum) samples after gamma irradiation. These samples were irradiated into plastic packages using a {sup 60}Co facility. Radiation doses applied were 0, 5, 10, 15, 20 and 25 kGy. For the analysis of the samples, solid-phase microextraction (SPME) was applied, while for the analysis of volatile compounds, CG/MS. Spice irradiation showed the highest decrease in volatile compounds. For L. cinnamomum, the irradiation decreased volatile compounds by nearly 56% and 89.5%, respectively, comparing to volatile from a sample which had not been previously irradiated.

  18. The applicability of fluoride volatility process to producing UF6 from yellow cake

    International Nuclear Information System (INIS)

    Xia Dechang

    2005-01-01

    The schematic diagrams producing UF 6 from yellow cake are showed in this paper. The characteristics and process improvements of the fluoride volatility process are explained. The applicability of the fluoride volatility process to producing UF 6 from yellow cake is discussed. (authors)

  19. Volatile compounds in samples of cork and also produced by selected fungi.

    Science.gov (United States)

    Barreto, M C; Vilas Boas, L; Carneiro, L C; San Romão, M V

    2011-06-22

    The production of volatile compounds by microbial communities of cork samples taken during the cork manufacturing process was investigated. The majority of volatiles were found in samples collected at two stages: resting after the first boiling and nontreated cork disks. Volatile profiles produced by microbiota in both stages are similar. The releasable volatile compounds and 2,4,6-trichloroanisole (TCA) produced in cork-based culture medium by five isolated fungal species in pure and mixed cultures were also analyzed by gas chromatography coupled with mass spectrometry (GC-MS).The results showed that 1-octen-3-ol and esters of fatty acids (medium chain length C8-C20) were the main volatile compounds produced by either pure fungal species or their mixture. Apparently, Penicillium glabrum is the main contributor to the overall volatile composition observed in the mixed culture. The production of releasable TCA on cork cannot be attributed to any of the assayed fungal isolates.

  20. Trapping female Pandemis limitata (Lepidoptera: Tortricidae) moths with mixtures of acetic acid, benzenoid apple leaf volatiles, and sex pheromones

    Science.gov (United States)

    Pandemis limitata (Robinson) is one of several leaf-feeding caterpillar pests of commercial tree-fruit crops in British Columbia. Recent discovery that European Pandemis spp. are attracted to lures containing acetic acid (AA) and caterpillar-induced benzenoid apple leaf volatiles, 2-phenylethanol a...

  1. Pheromone communication in Anastrepha obliqua (Diptera: Tephritidae): A comparison of the volatiles and salivary gland extracts of two wild populations

    Czech Academy of Sciences Publication Activity Database

    Goncalves, G. B.; Silva, C. E.; Mendonca, A. D. L.; Vaníčková, Lucie; Tomčala, Aleš; do Nascimento, R. R.

    2013-01-01

    Roč. 96, č. 4 (2013), s. 1365-1374 ISSN 0015-4040 Institutional support: RVO:61388963 Keywords : salivary glands * volatile compounds * sex attractant * wild population * gas chromatography - mass spectrometry Subject RIV: CE - Biochemistry Impact factor: 1.056, year: 2013

  2. Pheromonal Communication in the European House Dust Mite, Dermatophagoides pteronyssinus

    Directory of Open Access Journals (Sweden)

    Johannes L.M. Steidle

    2014-08-01

    Full Text Available Despite the sanitary importance of the European house dust mite Dermatophagoides pteronyssinus (Trouessart, 1897, the pheromonal communication in this species has not been sufficiently studied. Headspace analysis using solid phase micro extraction (SPME revealed that nerol, neryl formate, pentadecane, (6Z,9Z-6,9-heptadecadiene, and (Z-8-heptadecene are released by both sexes whereas neryl propionate was released by males only. Tritonymphs did not produce any detectable volatiles. In olfactometer experiments, pentadecane and neryl propionate were attractive to both sexes as well as to tritonymphs. (Z-8-heptadecene was only attractive to male mites. Therefore it is discussed that pentadecane and neryl propionate are aggregation pheromones and (Z-8-heptadecene is a sexual pheromone of the European house dust mite D. pteronyssinus. To study the potential use of pheromones in dust mite control, long-range olfactometer experiments were conducted showing that mites can be attracted to neryl propionate over distances of at least 50 cm. This indicates that mite pheromones might be useable to monitor the presence or absence of mites in the context of control strategies.

  3. Evidence for the presence of a female produced sex pheromone in the banana weevil, Cosmopolites sordidus Germar (Coleoptera: Curculionidae)

    Science.gov (United States)

    Behavior-modifying chemicals such as pheromones and kairomones have great potential in pest management. Studies reported here investigated chemical cues involved in mating and aggregation behavior of banana weevil, Cosmopolites sordidus, a major insect pest of banana in every country where bananas a...

  4. Identification of the aggregation pheromone of the melon thrips, Thrips palmi.

    Directory of Open Access Journals (Sweden)

    Sudhakar V S Akella

    Full Text Available The objective of this study was to identify the aggregation pheromone of the melon thrips Thrips palmi, a major pest of vegetable and ornamental plants around the world. The species causes damage both through feeding activities and as a vector of tospoviruses, and is a threat to world trade and European horticulture. Improved methods of detecting and controlling this species are needed and the identification of an aggregation pheromone will contribute to this requirement. Bioassays with a Y-tube olfactometer showed that virgin female T. palmi were attracted to the odour of live males, but not to that of live females, and that mixed-age adults of both sexes were attracted to the odour of live males, indicating the presence of a male-produced aggregation pheromone. Examination of the headspace volatiles of adult male T. palmi revealed only one compound that was not found in adult females. It was identified by comparison of its mass spectrum and chromatographic details with those of similar compounds. This compound had a structure like that of the previously identified male-produced aggregation pheromone of the western flower thrips Frankliniella occidentalis. The compound was synthesised and tested in eggplant crops infested with T. palmi in Japan. Significantly greater numbers of both males and females were attracted to traps baited with the putative aggregation pheromone compared to unbaited traps. The aggregation pheromone of T. palmi is thus identified as (R-lavandulyl 3-methyl-3-butenoate by spectroscopic, chromatographic and behavioural analysis.

  5. Identification of the aggregation pheromone of the melon thrips, Thrips palmi.

    Science.gov (United States)

    Akella, Sudhakar V S; Kirk, William D J; Lu, Yao-bin; Murai, Tamotsu; Walters, Keith F A; Hamilton, James G C

    2014-01-01

    The objective of this study was to identify the aggregation pheromone of the melon thrips Thrips palmi, a major pest of vegetable and ornamental plants around the world. The species causes damage both through feeding activities and as a vector of tospoviruses, and is a threat to world trade and European horticulture. Improved methods of detecting and controlling this species are needed and the identification of an aggregation pheromone will contribute to this requirement. Bioassays with a Y-tube olfactometer showed that virgin female T. palmi were attracted to the odour of live males, but not to that of live females, and that mixed-age adults of both sexes were attracted to the odour of live males, indicating the presence of a male-produced aggregation pheromone. Examination of the headspace volatiles of adult male T. palmi revealed only one compound that was not found in adult females. It was identified by comparison of its mass spectrum and chromatographic details with those of similar compounds. This compound had a structure like that of the previously identified male-produced aggregation pheromone of the western flower thrips Frankliniella occidentalis. The compound was synthesised and tested in eggplant crops infested with T. palmi in Japan. Significantly greater numbers of both males and females were attracted to traps baited with the putative aggregation pheromone compared to unbaited traps. The aggregation pheromone of T. palmi is thus identified as (R)-lavandulyl 3-methyl-3-butenoate by spectroscopic, chromatographic and behavioural analysis.

  6. Identification of the predominant volatile compounds produced by Aspergillus flavus.

    Science.gov (United States)

    Kamiński, E; Libbey, L M; Stawicki, S; Wasowicz, E

    1972-11-01

    A culture of Aspergillus flavus grown on moistened wheat meal was homogenized with a blendor, and the resulting slurry was vacuum-distilled at 5 mm of Hg and 35 C. The aqueous distillate was collected in traps cooled to -10 to -80 C. The culture volatiles were extracted from the distillate with CH(2)Cl(2), and, after removal of the bulk of the solvent, the concentrated volatiles were examined by packed-column gas chromatography. Nineteen peaks were observed, and coupled gas chromatography-mass spectrometry was employed to identify the larger components. The compounds identified were: 3-methyl-butanol, 3-octanone, 3-octanol, 1-octen-3-ol, 1-octanol, and cis-2-octen-1-ol. The two octenols were the predominant compounds, and sufficient sample was trapped from the gas chromatograph for infrared analyses; this confirmed the mass spectral identifications and permitted the assignment of the cis designation to 2-octen-1-ol. Both oct-1-en-3-ol and cis-2-octen-1-ol are thought to be responsible for the characteristic musty-fungal odor of certain fungi; the latter compound may be a useful chemical index of fungal growth.

  7. Volatile compounds of Aspergillus strains with different abilities to produce ochratoxin A.

    Science.gov (United States)

    Jeleń, Henryk H; Grabarkiewicz-Szczesna, Jadwiga

    2005-03-09

    Volatile compounds emitted by Aspergillus strains having different abilities to produce ochratoxin A were investigated. Thirteen strains of Aspergillus ochraceus, three belonging to the A. ochraceus group, and eight other species of Aspergillus were examined for their abilities to produce volatile compounds and ochratoxin A on a wheat grain medium. The profiles of volatile compounds, analyzed using SPME, in all A. ochraceus strains, regardless of their toxeginicity, were similar and comprised mainly of 1-octen-3-ol, 3-octanone, 3-octanol, 3-methyl-1-butanol, 1-octene, and limonene. The prevailing compound was always 1-octen-3-ol. Mellein, which forms part of the ochratoxin A molecule, was found in both toxigenic and nontoxigenic strains. Volatile compounds produced by other Aspergillus strains were similar to those of A. ochraceus. Incubation temperatures (20, 24, and 27 degrees C) and water content in the medium (20, 30, and 40%) influenced both volatile compounds formation and ochratoxin A biosynthesis efficiency, although conditions providing the maximum amount of volatiles were different from those providing the maximum amount of ochratoxin A. The pattern of volatiles produced by toxigenic A. ochraceus strains does not facilitate their differentiation from nontoxigenic strains.

  8. 40 CFR 180.1260 - Muscodor albus QST 20799 and the volatiles produced on rehydration; exemption from the...

    Science.gov (United States)

    2010-07-01

    ... volatiles produced on rehydration; exemption from the requirement of a tolerance. 180.1260 Section 180.1260... 20799 and the volatiles produced on rehydration; exemption from the requirement of a tolerance. An... Muscodor albus QST 20799, and the volatiles produced on its rehydration, when the pesticide is used for all...

  9. Volatiles produced by Staphylococcus xylosus and Staphylococcus carnosus during growth in sausage minces

    DEFF Research Database (Denmark)

    Stahnke, Marie Louise Heller

    1999-01-01

    Aseptic model minces were inoculated with commercial samples of either Staphylococcus xylosus or Staphylococcus carnosus. Volatiles produced by the cultures were collected during growth by diffusive sampling onto adsorbent traps, identified by thermal desorption-gas chromatography-mass spectrometry...... and quantified by thermal desorption-gas chromatography-flame ionisation. The data were analysed by principal component analysis. The study showed that both starter cultures produced a large number of volatiles in concentrations of sensory importance. Almost all of the major volatiles resulted from amino acid...... degradation, suggesting that the effect of Staphylococcus starter cultures on flavour quality is much related to their ability of catabolizing amino acids. With the exception of diacetyl, acetoin and 2-methyl-1-butanol, both cultures formed the same volatiles. Diacetyl and acetoin were not produced...

  10. Identification of a sex pheromone of the chrysanthemum lace bug Corythucha marmorata (Hemiptera: Tingidae).

    Science.gov (United States)

    Watanabe, Kisaki; Shimizu, Nobuhiro

    2017-08-04

    Although the nymphs of Corythucha marmorata form clusters on the undersides of host plant leaves, as frequently observed for Hemiptera, the adults are scattered in the vicinity of the nymph population. By investigating the biological activities of volatile secretions from the adult, we found that the secretions activated male mounting behaviour. A chemical analysis revealed that borneol was a common component of the secretions from both sexes. The absolute configuration of the natural product was the (+)-enantiomer of borneol and the optical isomer was undetectable. Although (+)-borneol showed significant sex pheromone activity against males, the antipode (-)-borneol also induced sex pheromone activity, albeit only slightly. Males may not have a strict identification mechanism based on stereochemistry. To verify the origin of this sex pheromone, we analysed the components of the essential oil of the leaves of Solidago canadensis L. (Compositae: Asteraceae), a host plant; bornyl acetate was detected to be a major component. The plant-produced bornyl acetate had different stereochemistry from the sex pheromone. The results suggested that the adults do not utilise the secondary metabolites of plants but biosynthesise this sex pheromone themselves. This is the first report on sex pheromone identification in Tingidae.

  11. Enhanced attraction of Plutella xylostella (Lepidoptera: Plutellidae) to pheromone-baited traps with the addition of green leaf volatiles

    Science.gov (United States)

    The GLVs, such as 1-hexanol and (Z)-3-hexen-1-ol, elicited strong electroantennographic responses from unmated male and female P. xylostella, whereas (Z)-3-hexenyl acetate only produced a relative weak response. The behavioral responses of unmated moths to GLVs were further tested in Y-tube olfactom...

  12. Fitness cost of pheromone production in signaling female moths.

    Science.gov (United States)

    Harari, Ally R; Zahavi, Tirtza; Thiéry, Denis

    2011-06-01

    A secondary sexual character may act as an honest signal of the quality of the individual if the trait bears a cost and if its expression is phenotypically condition dependent. The cost of increasing the trait should be tolerable for individuals in good condition but not for those in a poor condition. The trait thus provides an honest signal of quality that enables the receiver to choose higher quality mates. Evidence for sex pheromones, which play a major role in shaping sexual evolution, inflicting a signaling cost is scarce. Here, we demonstrate that the amount of the major component of the pheromone in glands of Lobesia botrana (Lepidoptera) females at signaling time was significantly greater in large than in small females, that male moths preferred larger females as mates when responding to volatile signals, and small virgin females, but not large ones, exposed to conspecific pheromone, produced, when mated, significantly fewer eggs than nonexposed females. The latter indicates a condition-dependent cost of signaling. These results are in accordance with the predictions of condition-dependent honest signals. We therefore suggest that female signaling for males using sex pheromones bears a cost and thus calling may serve as honest advertisement for female quality. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.

  13. Identification of Sex Pheromones and Sex Pheromone Mimics for Two North American Click Beetle Species (Coleoptera: Elateridae) in the Genus Cardiophorus Esch.

    Science.gov (United States)

    Serrano, Jacqueline M; Collignon, R Maxwell; Zou, Yunfan; Millar, Jocelyn G

    2018-04-01

    To date, all known or suspected pheromones of click beetles (Coleoptera: Elateridae) have been identified solely from species native to Europe and Asia; reports of identifications from North American species dating from the 1970s have since proven to be incorrect. While conducting bioassays of pheromones of a longhorned beetle (Coleoptera: Cerambycidae), we serendipitously discovered that males of Cardiophorus tenebrosus L. and Cardiophorus edwardsi Horn were specifically attracted to the cerambycid pheromone fuscumol acetate, (E)-6,10-dimethylundeca-5,9-dien-2-yl acetate, suggesting that this compound might also be a sex pheromone for the two Cardiophorus species. Further field bioassays and electrophysiological assays with the enantiomers of fuscumol acetate determined that males were specifically attracted by the (R)-enantiomer. However, subsequent analyses of extracts of volatiles from female C. tenebrosus and C. edwardsi showed that the females actually produced a different compound, which was identified as (3R,6E)-3,7,11-trimethyl-6,10-dodecadienoic acid methyl ester (methyl (3R,6E)-2,3-dihydrofarnesoate). In field trials, both the racemate and the (R)-enantiomer of the pheromone attracted similar numbers of male beetles, suggesting that the (S)-enantiomer was not interfering with responses to the insect-produced (R)-enantiomer. This report constitutes the first conclusive identification of sex pheromones for any North American click beetle species. Possible reasons for the strong and specific attraction of males to fuscumol acetate, which is markedly different in structure to the actual pheromone, are discussed.

  14. Volatiles produced by Staphylococcus xylosus and Staphylococcus carnosus during growth in sausage minces

    DEFF Research Database (Denmark)

    Stahnke, Marie Louise Heller

    1999-01-01

    of air. Volatiles produced by the cultures were collected during growth, identified and quantified. The data were analysed by partial least squares regression. The results showed that oxygen in general had more influence on the aroma producing capacity of Staphylococcus xylosus than of Staphylococcus...

  15. Female-induced increase of host-plant volatiles enhance specific attraction of aphid male Dysaphis plantaginea (Homoptera: Aphididae) to the sex pheromone

    NARCIS (Netherlands)

    Tol, van R.W.H.M.; Helsen, H.H.M.; Griepink, F.C.; Kogel, de W.J.

    2009-01-01

    All aphid species studied so far share the same sex pheromone components, nepetalactol and nepetalactone. Variation by different enantiomers and blends of the two components released by different aphid species are limited and can only partially explain species-specific attraction of males to

  16. (R)-3-hydroxyhexan-2-one is a major pheromone component of Anelaphus inflaticollis (Coleoptera: Cerambycidae).

    Science.gov (United States)

    Ray, A M; Swift, I P; Moreira, J A; Millar, J G; Hanks, L M

    2009-10-01

    We report the identification and field bioassays of a major component of the male-produced aggregation pheromone of Anelaphus inflaticollis Chemsak, an uncommon desert cerambycine beetle. Male A. inflaticollis produced a sex-specific blend of components that included (R)-3-hydroxyhexan-2-one, (S)-2-hydroxyhexan-3-one, 2,3-hexanedione, and (2R,3R)- and (2R,3S)-2,3-hexanediols. Field trials with baited bucket traps determined that the reconstructed synthetic pheromone blend and (R)-3-hydroxyhexan-2-one alone attracted adult A. inflaticollis of both sexes, with significantly more beetles being attracted to the blend. We conclude that (R)-3-hydroxyhexan-2-one is a major pheromone component of A. inflaticollis, and our results suggest that one or more of the minor components may further increase attraction of conspecifics. Scanning electron microscopy showed that male A. inflaticollis have pores on the prothorax that are consistent in structure with sex-specific pheromone gland pores in related species. Males also displayed stereotyped calling behavior similar to that observed in other cerambycine species. This study represents the first report of volatile pheromones for a cerambycine species in the tribe Elaphidiini.

  17. Pheromones and pheromone receptors are required for proper sexual development in the homothallic ascomycete Sordaria macrospora.

    Science.gov (United States)

    Mayrhofer, Severine; Weber, Jan M; Pöggeler, Stefanie

    2006-03-01

    The homothallic, filamentous ascomycete Sordaria macrospora is self-fertile and produces sexual fruiting bodies (perithecia) without a mating partner. Even so, S. macrospora transcriptionally expresses two pheromone-precursor genes (ppg1 and ppg2) and two pheromone-receptor genes (pre1 and pre2). The proteins encoded by these genes are similar to alpha-factor-like and a-factor-like pheromones and to G-protein-coupled pheromone receptors of the yeast Saccharomyces cerevisiae. It has been suggested that in S. macrospora, PPG1/PRE2 and PPG2/PRE1 form two cognate pheromone-receptor pairs. To investigate their function, we deleted (delta) pheromone-precursor genes (delta ppg1, delta ppg2) and receptor genes (delta pre1, delta pre2) and generated single- as well as double-knockout strains. No effect on vegetative growth, fruiting-body, and ascospore development was seen in the single pheromone-mutant and receptor-mutant strains, respectively. However, double-knockout strains lacking any compatible pheromone-receptor pair (delta pre2/delta ppg2, delta pre1/delta ppg1) and the double-pheromone mutant (delta ppg1/delta ppg2) displayed a drastically reduced number of perithecia and sexual spores, whereas deletion of both receptor genes (delta pre1/delta pre2) completely eliminated fruiting-body and ascospore formation. The results suggest that pheromones and pheromone receptors are required for optimal sexual reproduction of the homothallic S. macrospora.

  18. Identification of the Female-Produced Sex Pheromone of an Invasive Greenhouse Pest, the European Pepper Moth (Duponchelia fovealis).

    Science.gov (United States)

    Molnár, Péter Béla; Bognár, Csengele; Erdei, Anna Laura; Fujii, Takeshi; Vági, Pál; Jósvai, Júlia Katalin; Kárpáti, Zsolt

    2018-03-01

    The European pepper moth (Duponchelia fovealis, Lepidoptera, Crambidae, Spilomelinae) is an invasive pest of greenhouses in many countries, causing serious damages to horticultural plants. Coupled gas chromatographic-electroantennographic detection analysis of the female gland extract revealed two antennally active peaks. Using coupled gas chromatography-mass spectrometry (GC-MS), one was identified as (Z)-11-hexadecenal (Z11-16:Ald); however, further analysis on different types of capillary columns indicated that the second active compound has two different isomers, (E)-13-octadecenal (E13-18:Ald) and (Z)-13-octadecenal (Z13-18:Ald). The approximate ratio of E13-18:Ald, Z13-18:Ald and Z11-16:Ald in the crude pheromone gland extract was 10:1:0.1, respectively. Single sensillum recordings showed that there was one sensory neuron that responded with a high amplitude spike to both E13-18:Ald and Z13-18:Ald, while another neuron housed in the same sensillum responded to Z11-16:Ald. Field evaluation of the identified compounds indicated that the E13-18:Ald was necessary to evoke the attraction of males; although the presence of Z13-18:Ald and Z11-16:Ald increased the catches in traps. The highest number of caught males was achieved when E13-18:Ald, Z13-18:Ald and Z11-16:Ald were present in baits in the same ratio as in the female gland extract. This pheromone can be used in a monitoring strategy and could potentially lead to the development of mating disruption.

  19. Boll weevil (Coleoptera: Curculionidae) response to and volatilization rates of grandlure when combined with varying doses of eugenol in the extended-life pheromone lure.

    Science.gov (United States)

    Armstrong, J S

    2010-04-01

    Boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), trapping and pheromone quantitative analysis of extended-life pheromone lures manufactured with 0, 10, 20, and 30 mg of eugenol was conducted in the Rio Grande Valley of Texas under spring and summer conditions. Boll weevils responded positively to eugenol on one of 12 trapping weeks when densities were high, but when densities were low (30 degrees C, accumulative grandlure loss per week may be too high, leaving too little residual grandlure to effectively attract boll weevils at the end of 3 wk of trapping. Eugenol plays no role in reserving or encouraging the release of grandlure, or in increasing boll weevil captures when boll weevil densities are low.

  20. Caryolan-1-ol, an antifungal volatile produced by Streptomyces spp., inhibits the endomembrane system of fungi.

    Science.gov (United States)

    Cho, Gyeongjun; Kim, Junheon; Park, Chung Gyoo; Nislow, Corey; Weller, David M; Kwak, Youn-Sig

    2017-07-01

    Streptomyces spp. have the ability to produce a wide variety of secondary metabolites that interact with the environment. This study aimed to discover antifungal volatiles from the genus Streptomyces and to determine the mechanisms of inhibition. Volatiles identified from Streptomyces spp. included three major terpenes, geosmin, caryolan-1-ol and an unknown sesquiterpene. antiSMASH and KEGG predicted that the volatile terpene synthase gene clusters occur in the Streptomyces genome. Growth inhibition was observed when fungi were exposed to the volatiles. Biological activity of caryolan-1-ol has previously not been investigated. Fungal growth was inhibited in a dose-dependent manner by a mixture of the main volatiles, caryolan-1-ol and the unknown sesquiterpene, from Streptomyces sp. S4-7. Furthermore, synthesized caryolan-1-ol showed similar antifungal activity. Results of chemical-genomics profiling assays showed that caryolan-1-ol affected the endomembrane system by disrupting sphingolipid synthesis and normal vesicle trafficking in the fungi. © 2017 The Authors.

  1. Age-related and Individual Variation in Male Piezodorus hybneri (Heteroptera: Pentatomidae Pheromones

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    Nobuyuki Endo

    2012-01-01

    Full Text Available Males of the Piezodorus hybneri stink bug produce a pheromone comprising β-sesquiphellandrene (Sesq, (R-15-hexadecanolide (R15, and methyl (Z-8-hexadecenoate (Z8. We collected airborne volatiles from individual P. hybneri males and analyzed them by GC-MS. Daily analysis from 1 to 16 days after adult emergence showed that pheromone emission started around 3 to 6 days after adult emergence and peaked (~1 μg/male/day on day 11. The proportion of Sesq tended to increase with age to about 80% on days 12 to 16. On the other hand, the proportion of R15 tended to decrease with age. The proportion of Z8 reached a maximum of about 34% on day 9 but otherwise remained below 20%. The total amount of pheromone emitted by individual males varied considerably: three males emitted more than 10 μg, whereas another three males emitted little or no pheromone and failed to survive by the end of the experiment. These results suggest that the amount of P. hybneri pheromone and its blend ratio could be affected by the male’s physical conditions, such as vitality and age.

  2. Attraction of spathius agrili yang (Hymenoptera: eulophidae) to male-produced "aggregation-sex pheromone:" differences between the sexes and mating status

    Science.gov (United States)

    Male and female Spathius agrili Yang were tested for attraction to the synthetic male pheromone. Lures consisting of a 3-component pheromone blend were placed in the center of a white filter paper target used to activate upwind flight in the wind tunnel. When virgin males and females were tested for...

  3. Characterization of Volatile Compounds of Bulgur (Antep Type Produced from Durum Wheat

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    Saad Ibrahim Yousif

    2018-01-01

    Full Text Available Bulgur is enjoyed and rediscovered by many people as a stable food because of its color, flavor, aroma, texture, and nutritional and economical values. There is more than one type of bulgur overall the world according to production techniques and raw materials. The volatile compounds of bulgur have not been explored yet. In this study, Headspace Solid Phase Microextraction (HS-SPME and Gas Chromatography–Mass Spectroscopy (GS-MS methods were used to determine the volatile flavor compounds of bulgur (Antep type, produced from Durum wheat. Approaching studies were used and the results were optimized to determine the ideal conditions for the extraction and distinguish the compounds responsible for the flavor of bulgur. Approximately, 47 and 37 important volatile compounds were determined for Durum wheat and bulgur, respectively. The study showed that there was a great diversity of volatiles in bulgur produced using Durum wheat and Antep type production method. These can lead to a better understanding of the combination of compounds that give a unique flavor with more researches.

  4. Grains colonised by moulds: fungal identification and headspace analysis of produced volatile metabolites

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    Maria Paola Tampieri

    2010-01-01

    Full Text Available The aim of this work was to verify if the headspace analysis of fungal volatile compounds produced by some species of Fusarium can be used as a marker of mould presence on maize. Eight samples of maize (four yellow maize from North Italy and four white maize from Hungary, naturally contaminated by Fusarium and positive for the presence of fumonisins, were analyzed to detect moisture content, Aw, volatile metabolites and an enumeration of viable moulds was performed by means of a colony count technique. Headspace samples were analysed using a gas-chromatograph equipped with a capillary column TR-WAX to detect volatile metabolites of moulds. Furthermore macro and microscopic examination of the colonies was performed in order to distinguish, according to their morphology, the genera of the prevalent present moulds. Prevalent mould of eight samples was Fusarium, but other fungi, like Aspergillus, Penicillum and Mucoraceae, were observed. The metabolites produced by F.graminearum and F. moniliforme were Isobutyl-acetate, 3-Methyl-1-butanol and, only at 8 days, 3-Octanone. The incubation time can affect off flavour production in consequence of the presence of other moulds. Further studies on maize samples under different conditions are needed in order to establish the presence of moulds using the count technique and through the identification of volatile compounds.

  5. Coincidence of pheromone and plant odor leads to sensory plasticity in the heliothine olfactory system.

    Directory of Open Access Journals (Sweden)

    Elena Ian

    Full Text Available Male moths possess a highly specialized olfactory system comprised of two segregated sub-arrangements dedicated to processing information about plant odors and pheromones, respectively. Communication between these two sub-systems has been described at the peripheral level, but relatively little is known about putative interactions at subsequent synaptic relays. The male moth faces the challenge of seeking out the conspecific female in a highly dynamic odor world. The female-produced pheromone blend, which is a limited resource serving as guidance for the male, will reach his antennae in intermittent pockets of odor filaments mixed with volatiles from various plants. In the present study we performed calcium imaging for measuring odor-evoked responses in the uni-glomerular antennal-lobe projection neurons (analog to mitral cells in the vertebrate olfactory bulb of Helicoverpa armigera. In order to investigate putative interactions between the two sub-systems tuned to plant volatiles and pheromones, respectively, we performed repeated stimulations with a selection of biologically relevant odors. We found that paired stimulation with a plant odor and the pheromone led to suppressed responses in both sub-systems as compared to those evoked during initial stimulation including application of each odor stimulus alone. The fact that the suppression persisted also after pairing, indicates the existence of a Hebbian-like plasticity in the primary olfactory center established by temporal pairing of the two odor stimulation categories.

  6. Innate recognition of pheromone and food odors in moths: a common mechanism in the antennal lobe?

    Directory of Open Access Journals (Sweden)

    Joshua P Martin

    2010-09-01

    Full Text Available The survival of an animal often depends on an innate response to a particular sensory stimulus. For an adult male moth, two categories of odors are innately attractive: pheromone released by conspecific females, and the floral scents of certain, often co-evolved, plants. These odors consist of multiple volatiles in characteristic mixtures. Here, we review evidence that both categories of odors are processed as sensory objects, and we suggest a mechanism in the primary olfactory center, the antennal lobe (AL, that encodes the configuration of these mixtures and may underlie recognition of innately attractive odors. In the pheromone system, mixtures of two or three volatiles elicit upwind flight. Peripheral changes are associated with behavioral changes in speciation, and suggest the existence of a pattern recognition mechanism for pheromone mixtures in the AL. Moths are similarly innately attracted to certain floral scents. Though floral scents consist of multiple volatiles that activate a broad array of receptor neurons, only a smaller subset, numerically comparable to pheromone mixtures, is necessary and sufficient to elicit behavior. Both pheromone and floral scent mixtures that produce attraction to the odor source elicit synchronous action potentials in particular populations of output (projection neurons (PNs in the AL. We propose a model in which the synchronous output of a population of PNs encodes the configuration of an innately attractive mixture, and thus comprises an innate mechanism for releasing odor-tracking behavior. The particular example of olfaction in moths may inform the general question of how sensory objects trigger innate responses.

  7. Volatile profiles and chromatic characteristics of red wines produced with Starmerella bacillaris and Saccharomyces cerevisiae.

    Science.gov (United States)

    Englezos, Vasileios; Rantsiou, Kalliopi; Cravero, Francesco; Torchio, Fabrizio; Giacosa, Simone; Ortiz-Julien, Anne; Gerbi, Vincenzo; Rolle, Luca; Cocolin, Luca

    2018-07-01

    The use of mixed fermentations with Starmerella bacillaris and Saccharomyces cerevisiae is gaining attention in recent years due to their ability to modulate the metabolites production of enological interest. In the present study, four of the most popular planted red grape varieties (Cabernet sauvignon, Merlot, Pinot noir and Shiraz) were fermented using the aforementioned species and two different inoculation protocols (inoculation of S. cerevisiae after 24 and 48 h from the Starm. bacillaris inoculation), in order to evaluate their impact on the volatile composition and chromatic characteristics of wines. Analysis from chemical composition showed that titratable acidity and glycerol content exhibited marked differences among wines after fermentation. For volatile compounds, mixed fermented wines using an inoculation delay of 48 h led to reduction of volatile compounds (mainly esters). A shorter 24 h delay produced wines with higher values of color intensity than pure fermented wines. The differences observed between the inoculation protocols can be explained by the growth dynamics of both species during fermentation. These findings suggest that mixed fermentations posed a great potential in reducing metabolites which are considered negative for wine quality (mainly ethyl acetate and volatile fatty acids) and with an improvement of the chromatic profile of the wines. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. A temporal comparison of sex-aggregation pheromone gland content and dynamics of release in three members of the Lutzomyia longipalpis (Diptera: Psychodidae species complex.

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    Mikel A González

    2017-12-01

    Full Text Available Lutzomyia longipalpis is the South American vector of Leishmania infantum, the etiologic agent of visceral leishmaniasis (VL. Male L. longipalpis produce a sex-aggregation pheromone that is critical in mating, yet very little is known about its accumulation over time or factors involved in release. This laboratory study aimed to compare accumulation of pheromone over time and determine factors that might influence release in three members of the L. longipalpis species complex.We investigated male sex-aggregation pheromone gland content at different ages and the release rate of pheromone in the presence or absence of females under different light conditions by gas chromatography-mass spectrometry (GC-MS. Pheromone gland content was determined by extraction of whole males and pheromone release rate was determined by collection of headspace volatiles. Pheromone gland content appeared age-related and pheromone began to accumulate between 6 to 12 h post eclosion and gradually increased until males were 7-9 days old. The greatest amount was detected in 9-day old Campo Grande males ((S-9-methylgermacrene-B; X ± SE: 203.5 ± 57.4 ng/male followed by Sobral 2S males (diterpene; 199.9 ± 34.3 and Jacobina males ((1S,3S,7R-3-methyl-α-himachalene; 128.8 ± 30.3 at 7 days old. Pheromone release was not continuous over time. During a 4-hour period, the greatest quantities of pheromone were released during the first hour, when wing beating activity was most intense. It was then substantially diminished for the remainder of the time. During a 24 h period, 4-5 day old male sand flies released approximately 63 ± 11% of the pheromone content of their glands, depending on the chemotype. The presence of females significantly increased pheromone release rate. The light regime under which the sand flies were held had little influence on pheromone release except on Sobral 2S chemotype.Accumulation of pheromone appears to occur at different rates in the different

  9. A temporal comparison of sex-aggregation pheromone gland content and dynamics of release in three members of the Lutzomyia longipalpis (Diptera: Psychodidae) species complex.

    Science.gov (United States)

    González, Mikel A; Bandi, Krishna K; Bell, Melissa J; Brazil, Reginaldo P; Dilger, Erin; Guerrero, Angel; Courtenay, Orin; Hamilton, James G C

    2017-12-01

    Lutzomyia longipalpis is the South American vector of Leishmania infantum, the etiologic agent of visceral leishmaniasis (VL). Male L. longipalpis produce a sex-aggregation pheromone that is critical in mating, yet very little is known about its accumulation over time or factors involved in release. This laboratory study aimed to compare accumulation of pheromone over time and determine factors that might influence release in three members of the L. longipalpis species complex. We investigated male sex-aggregation pheromone gland content at different ages and the release rate of pheromone in the presence or absence of females under different light conditions by gas chromatography-mass spectrometry (GC-MS). Pheromone gland content was determined by extraction of whole males and pheromone release rate was determined by collection of headspace volatiles. Pheromone gland content appeared age-related and pheromone began to accumulate between 6 to 12 h post eclosion and gradually increased until males were 7-9 days old. The greatest amount was detected in 9-day old Campo Grande males ((S)-9-methylgermacrene-B; X ± SE: 203.5 ± 57.4 ng/male) followed by Sobral 2S males (diterpene; 199.9 ± 34.3) and Jacobina males ((1S,3S,7R)-3-methyl-α-himachalene; 128.8 ± 30.3) at 7 days old. Pheromone release was not continuous over time. During a 4-hour period, the greatest quantities of pheromone were released during the first hour, when wing beating activity was most intense. It was then substantially diminished for the remainder of the time. During a 24 h period, 4-5 day old male sand flies released approximately 63 ± 11% of the pheromone content of their glands, depending on the chemotype. The presence of females significantly increased pheromone release rate. The light regime under which the sand flies were held had little influence on pheromone release except on Sobral 2S chemotype. Accumulation of pheromone appears to occur at different rates in the different chemotypes

  10. The chemical volatiles (semiochemicals) produced by neo tropical stink bugs (Hemiptera: Pentatomidae)

    Energy Technology Data Exchange (ETDEWEB)

    Moraes, Maria C.B.; Pareja, Martin; Laumann, Raul A.; Borges, Miguel [EMBRAPA Recursos Geneticos e Biotecnologia, Brasilia, DF (Brazil). Nucleo Tematico Controle Biologico

    2008-09-15

    In recent years the growing concern about environmental changes and how we are using the natural resources have triggered a search for natural products as alternatives to synthetic pesticides. The stink bugs produce a wide variety of chemical compounds (semiochemicals) that show potential to manage these insects. The stink bugs Chinavia impicticornis (Stal), C. ubica (Rolston), Dichelops melacanthus (Dallas), Euschistus heros (F.), Piezodorus guildinii (Westwood), Thyanta perditor (Westwood) and Tibraca limbativentris (Stal) had their blends of defensive compounds evaluated both qualitative and quantitatively. The main compounds identified on the glands of Brazilian stink bugs are: 2-alkenals, mainly the E isomer; saturated aliphatic hydrocarbons; and 4 oxo-(E)-2-alkenals. The first sex attractant determined from a stink bug was obtained from Nezara viridula L., and consists on a mix of two isomers cis - and trans bisabolene-epoxides. Later the soybean stink bug E. heros was also studied and its sex attractant was identified as three esters methyl: 2,6,10-trimethyl decanoate, methyl 2,6,10-trimethyl dodecanoate, and methyl E2, Z4-decadienoate. Recently, three new Brazilian sting bugs were studied and had their sex attractant elucidated. Males of T. perditor produce the ester, methyl 2E, 4Z, 6Z-decatrienoate. Whereas, the stink bug, P. guildinii has as sexual pheromone, the sesquiterpene beta-sesqui phellandrene, and the stink bug T. limbativentris produces as sex attractant the zingiberenol. In this review we discuss the advances obtained on the behaviour and identification of sex and defensive compound of stink bugs from Brazilian crops and the application of this knowledge to manage the stink bugs. (author)

  11. The chemical volatiles (semiochemicals) produced by neo tropical stink bugs (Hemiptera: Pentatomidae)

    International Nuclear Information System (INIS)

    Moraes, Maria C.B.; Pareja, Martin; Laumann, Raul A.; Borges, Miguel

    2008-01-01

    In recent years the growing concern about environmental changes and how we are using the natural resources have triggered a search for natural products as alternatives to synthetic pesticides. The stink bugs produce a wide variety of chemical compounds (semiochemicals) that show potential to manage these insects. The stink bugs Chinavia impicticornis (Stal), C. ubica (Rolston), Dichelops melacanthus (Dallas), Euschistus heros (F.), Piezodorus guildinii (Westwood), Thyanta perditor (Westwood) and Tibraca limbativentris (Stal) had their blends of defensive compounds evaluated both qualitative and quantitatively. The main compounds identified on the glands of Brazilian stink bugs are: 2-alkenals, mainly the E isomer; saturated aliphatic hydrocarbons; and 4 oxo-(E)-2-alkenals. The first sex attractant determined from a stink bug was obtained from Nezara viridula L., and consists on a mix of two isomers cis - and trans bisabolene-epoxides. Later the soybean stink bug E. heros was also studied and its sex attractant was identified as three esters methyl: 2,6,10-trimethyl decanoate, methyl 2,6,10-trimethyl dodecanoate, and methyl E2, Z4-decadienoate. Recently, three new Brazilian sting bugs were studied and had their sex attractant elucidated. Males of T. perditor produce the ester, methyl 2E, 4Z, 6Z-decatrienoate. Whereas, the stink bug, P. guildinii has as sexual pheromone, the sesquiterpene beta-sesqui phellandrene, and the stink bug T. limbativentris produces as sex attractant the zingiberenol. In this review we discuss the advances obtained on the behaviour and identification of sex and defensive compound of stink bugs from Brazilian crops and the application of this knowledge to manage the stink bugs. (author)

  12. Ratiometric Decoding of Pheromones for a Biomimetic Infochemical Communication System

    Directory of Open Access Journals (Sweden)

    Guangfen Wei

    2017-10-01

    Full Text Available Biosynthetic infochemical communication is an emerging scientific field employing molecular compounds for information transmission, labelling, and biochemical interfacing; having potential application in diverse areas ranging from pest management to group coordination of swarming robots. Our communication system comprises a chemoemitter module that encodes information by producing volatile pheromone components and a chemoreceiver module that decodes the transmitted ratiometric information via polymer-coated piezoelectric Surface Acoustic Wave Resonator (SAWR sensors. The inspiration for such a system is based on the pheromone-based communication between insects. Ten features are extracted from the SAWR sensor response and analysed using multi-variate classification techniques, i.e., Linear Discriminant Analysis (LDA, Probabilistic Neural Network (PNN, and Multilayer Perception Neural Network (MLPNN methods, and an optimal feature subset is identified. A combination of steady state and transient features of the sensor signals showed superior performances with LDA and MLPNN. Although MLPNN gave excellent results reaching 100% recognition rate at 400 s, over all time stations PNN gave the best performance based on an expanded data-set with adjacent neighbours. In this case, 100% of the pheromone mixtures were successfully identified just 200 s after they were first injected into the wind tunnel. We believe that this approach can be used for future chemical communication employing simple mixtures of airborne molecules.

  13. Volatility

    Directory of Open Access Journals (Sweden)

    María Sánchez

    2016-11-01

    Full Text Available The action consists of moving with small kicks a tin of cola refresh -without Brand-from a point of the city up to other one. During the path I avoid bollards, the slope differences between sidewalks, pedestrians, parked motorcycles, etc. Volatility wants to say exactly that the money is getting lost. That the money is losing by gentlemen and by ladies who are neither financial sharks, nor big businessmen… or similarly, but ingenuous people, as you or as me, who walk down the street.

  14. A process for producing lignin and volatile compounds from hydrolysis liquor.

    Science.gov (United States)

    Khazraie, Tooran; Zhang, Yiqian; Tarasov, Dmitry; Gao, Weijue; Price, Jacquelyn; DeMartini, Nikolai; Hupa, Leena; Fatehi, Pedram

    2017-01-01

    Hot water hydrolysis process is commercially applied for treating wood chips prior to pulping or wood pellet production, while it produces hydrolysis liquor as a by-product. Since the hydrolysis liquor is dilute, the production of value-added materials from it would be challenging. In this study, acidification was proposed as a viable method to extract (1) furfural and acetic acid from hot water hydrolysis liquor and (2) lignin compounds from the liquor. The thermal properties of the precipitates made from the acidification of hydrolysis liquor confirmed the volatile characteristics of precipitates. Membrane dialysis was effective in removing inorganic salts associated with lignin compounds. The purified lignin compounds had a glass transition temperature (Tg) of 180-190 °C, and were thermally stable. The results confirmed that lignin compounds present in hot water hydrolysis liquor had different characteristics. The acidification of hydrolysis liquor primarily removed the volatile compounds from hydrolysis liquor. Based on these results, a process for producing purified lignin and precipitates of volatile compounds was proposed.

  15. Characterization of volatile compounds produced by Lactobacillus helveticus strains in a hard cheese model.

    Science.gov (United States)

    Cuffia, Facundo; Bergamini, Carina V; Wolf, Irma V; Hynes, Erica R; Perotti, María C

    2018-01-01

    Starter cultures of Lactobacillus helveticus used in hard cooked cheeses play an important role in flavor development. In this work, we studied the capacity of three strains of L. helveticus, two autochthonous (Lh138 and Lh209) and one commercial (LhB02), to grow and to produce volatile compounds in a hard cheese extract. Bacterial counts, pH, profiles of organic acids, carbohydrates, and volatile compounds were analyzed during incubation of extracts for 14 days at 37 ℃. Lactobacilli populations were maintained at 10 6 CFU ml -1 for Lh138, while decreases of approx. 2 log orders were found for LhB02 and Lh209. Both Lh209 and LhB02 slightly increased the acetic acid content whereas mild increase in lactic acid was produced by Lh138. The patterns of volatiles were dependent on the strain which reflect their distinct enzymatic machineries: LhB02 and Lh209 produced a greater diversity of compounds, while Lh138 was the least producer strain. Extracts inoculated with LhB02 and Lh 209 were characterized by ketones, esters, alcohols, aldehydes, and acids, whereas in the extracts with Lh138 the main compounds belonged to aromatic, aldehydes, and ketones groups. Therefore, Lh209 and LhB02 could represent the best cheese starters to improve and intensify the flavor, and even a starter composed by combinations of LhB02 or Lh209 with Lh138 could also be a strategy to diversify cheese flavor.

  16. Volatile Flavor Compounds Produced by Molds of Aspergillus, Penicillium, and Fungi imperfecti.

    Science.gov (United States)

    Kaminski, E; Stawicki, S; Wasowicz, E

    1974-06-01

    Strains of molds Aspergillus niger, A. ochraceus, A. oryzae, A. parasiticus, Penicillium chrysogenum, P. citrinum, P. funiculosum, P. raistrickii, P. viridicatum, Alternaria, Cephalosporium, and Fusarium sp. were grown on sterile coarse wheat meal at 26 to 28 C for 120 h. The volatiles from mature cultures were distilled at low temperature under reduced pressure. The distillates from traps -40 and -78 C were extracted with methylene chloride and subsequently concentrated. All the concentrates thus obtained were analyzed by gas-liquid chromatography, mass spectrometry, chemical reactions of functional groups, and olfactory evaluation. Six components detected in the culture distillates were identified positively: 3-methylbutanol, 3-octanone, 3-octanol, 1-octen-3-ol, 1-octanol, and 2-octen-1-ol. They represented 67 to 97% of all the volatiles occurring in the concentrated distillate. The following 14 components were identified tentatively: octane, isobutyl alcohol, butyl alcohol, butyl acetate, amyl acetate, octyl acetate, pyridine, hexanol, nonanone, dimethylpyrazine, tetramethylpyrazine, benzaldehyde, propylbenzene, and phenethyl alcohol. Among the volatiles produced by molds, 1-octen-3-ol yielding a characteristic fungal odor was found predominant.

  17. A Drosophila protein family implicated in pheromone perception is related to Tay-Sachs GM2-activator protein.

    Science.gov (United States)

    Starostina, Elena; Xu, Aiguo; Lin, Heping; Pikielny, Claudio W

    2009-01-02

    Low volatility, lipid-like cuticular hydrocarbon pheromones produced by Drosophila melanogaster females play an essential role in triggering and modulating mating behavior, but the chemosensory mechanisms involved remain poorly understood. Recently, we showed that the CheB42a protein, which is expressed in only 10 pheromone-sensing taste hairs on the front legs of males, modulates progression to late stages of male courtship behavior in response to female-specific cuticular hydrocarbons. Here we report that expression of all 12 genes in the CheB gene family is predominantly or exclusively gustatory-specific, and occurs in many different, often non-overlapping patterns. Only the Gr family of gustatory receptor genes displays a comparable variety of gustatory-specific expression patterns. Unlike Grs, however, expression of all but one CheB gene is sexually dimorphic. Like CheB42a, other CheBs may therefore function specifically in gustatory perception of pheromones. We also show that CheBs belong to the ML superfamily of lipid-binding proteins, and are most similar to human GM2-activator protein (GM2-AP). In particular, GM2-AP residues involved in ligand binding are conserved in CheBs but not in other ML proteins. Finally, CheB42a is specifically secreted into the inner lumen of pheromone-sensing taste hairs, where pheromones interact with membrane-bound receptors. We propose that CheB proteins interact directly with lipid-like Drosophila pheromones and modulate their detection by the gustatory signal transduction machinery. Furthermore, as loss of GM2-AP in Tay-Sachs disease prevents degradation of GM2 gangliosides and results in neurodegeneration, the function of CheBs in pheromone response may involve biochemical mechanisms critical for lipid metabolism in human neurons.

  18. A Drosophila Protein Family Implicated in Pheromone Perception Is Related to Tay-Sachs GM2-Activator Protein*

    Science.gov (United States)

    Starostina, Elena; Xu, Aiguo; Lin, Heping; Pikielny, Claudio W.

    2009-01-01

    Low volatility, lipid-like cuticular hydrocarbon pheromones produced by Drosophila melanogaster females play an essential role in triggering and modulating mating behavior, but the chemosensory mechanisms involved remain poorly understood. Recently, we showed that the CheB42a protein, which is expressed in only 10 pheromone-sensing taste hairs on the front legs of males, modulates progression to late stages of male courtship behavior in response to female-specific cuticular hydrocarbons. Here we report that expression of all 12 genes in the CheB gene family is predominantly or exclusively gustatory-specific, and occurs in many different, often non-overlapping patterns. Only the Gr family of gustatory receptor genes displays a comparable variety of gustatory-specific expression patterns. Unlike Grs, however, expression of all but one CheB gene is sexually dimorphic. Like CheB42a, other CheBs may therefore function specifically in gustatory perception of pheromones. We also show that CheBs belong to the ML superfamily of lipid-binding proteins, and are most similar to human GM2-activator protein (GM2-AP). In particular, GM2-AP residues involved in ligand binding are conserved in CheBs but not in other ML proteins. Finally, CheB42a is specifically secreted into the inner lumen of pheromone-sensing taste hairs, where pheromones interact with membrane-bound receptors. We propose that CheB proteins interact directly with lipid-like Drosophila pheromones and modulate their detection by the gustatory signal transduction machinery. Furthermore, as loss of GM2-AP in Tay-Sachs disease prevents degradation of GM2 gangliosides and results in neurodegeneration, the function of CheBs in pheromone response may involve biochemical mechanisms critical for lipid metabolism in human neurons. PMID:18952610

  19. Potential of volatile compounds produced by fungi to influence sensory quality of coffee beverage

    DEFF Research Database (Denmark)

    Iamanaka, B. T.; Teixeira, A. A.; Teixeira, A. R. R.

    2014-01-01

    Fungi are known producers of a large number of volatile compounds (VCs). Several VCs such as 2,4,6 trichloroanisole (TCA), geosmin and terpenes have been found in coffee beverages, and these compounds can be responsible for off-flavor development. However, few studies have related the fungal...... contamination of coffee with the sensory characteristics of the beverage. The aim of this research was to investigate the production of VCs by fungi isolated from coffee and their potential as modifiers of the sensory coffee beverage quality. Three species were isolated from coffee from the southwest of São...... Paulo state and selected for the study: Penicillium brevicompactum, Aspergillus luchuensis (belonging to section Nigri) and Penicillium sp. nov. (related to Penicillium crustosum). VCs produced by the fungal inoculated in raw coffee beans were extracted and tentatively identified by SPME...

  20. Identification and Behavioral Evaluation of Sex Pheromone in Xanthopimpla pedator (Fabricius—A Serious Pupal Parasitoid of Tropical Tasar Silkworm Anthereae mylitta Drury

    Directory of Open Access Journals (Sweden)

    Lakshmi Marepally

    2016-10-01

    Full Text Available Xanthopimpla is a major parasitoid of silk worm cocoons. The female Xanthopimpla pedator (Fabricius lays the eggs in male cocoons. Control of this infestation with pesticides is not recommended because of its concealed behavior. Various control methods were found to be inefficient. Ecofriendly management is the best strategy that can be applied. We have studied the sex communication in Xanthopimpla pedator (Fabricius, which helps to develop management strategy. Bioassays were done in the laboratory by using olfactometer and pheromone extraction chambers. It was found that female Xanthopimpla produces sex pheromones. The results show a strong attraction of male by female Xanthopimpla. Present results with male and female volatiles also show that female volatiles attract male Xanthopimpla. Fractionation of female volatiles by column chromatography has proven that 20% fraction has highest attraction of males by females.

  1. Inter- and Intrapopulation Variation of the Pheromone, Ipsdienol Produced by Male Pine Engravers Ips pini (Say) (Coleoptera: Scolytidae)

    Science.gov (United States)

    D.R. Miller; J.H. Borden; K.N. Slessor

    1989-01-01

    We determined the chirality of ipsdienol in individual male pine engravers, Ips pini (Say), from New York, California, and two localities in British Columbia (BC). Both quantity and chirality of ipsdienol varied significantly between and within populations of I. pini . Beetles from California and southeastern BC produced...

  2. Use of solid phase microextraction (SPME) for profiling the volatile metabolites produced by Glomerella cingulata.

    Science.gov (United States)

    Miyazawa, Mitsuo; Kimura, Minako; Yabe, Yoshito; Tsukamoto, Daisuke; Sakamoto, Masaya; Horibe, Isao; Okuno, Yoshiharu

    2008-01-01

    The profile of volatile organic compounds (VOCs) released from Glomerella cingulata using solid phase microextraction (SPME) with different fibers, Polydimethylsiloxane (PDMS), Polydimethylsiloxane/Divinylbenzene (PDMS/DVB), Carboxen/Polydimethylsiloxane (CAR/PDMS) and Divinylbenzene/Carboxen/Polydimethylsiloxane (DVB/CAR/PDMS), was investigated. C4-C6 aliphatic alcohols were the predominant fraction of VOCs isolated by CAR/PDMS fiber. Sesquiterpene hydrocarbons represented 20.3% of VOCs isolated by PDMS fiber. During the growth phase, Ochracin was produced in the large majority of VOCs. 3-Methylbutanol and phenylethyl alcohol were found in the log phase of it. Alcohols were found in cultures of higher age, while sesquiterpenes were found to be characteristic of initial growth stage of G. cingulata.

  3. Sensory and volatile profiles of monofloral honeys produced by native stingless bees of the brazilian semiarid region.

    Science.gov (United States)

    Costa, Ana Caroliny Vieira da; Sousa, Janaína Maria Batista; da Silva, Maria Aparecida Azevedo Pereira; Garruti, Deborah Dos Santos; Madruga, Marta Suely

    2018-03-01

    Monofloral honeys produced by stingless bees M. subnitida Ducke and M. scutellaris Latrelle in typical flowering of the Brazilian semi-arid Ziziphus juazeiro Mart (juazeiro), Croton heliotropiifolius Kunth (velame branco) and Mimosa arenosa willd Poir (jurema branca) were characterized in relation to volatile and sensorial profile. It identified 11 sensory descriptors and 96 volatile compounds. It was noticed a strong effect of flowering in sensorial profile and volatile of honeys. Juazeiro honey stood out with a higher characteristic aroma, taste sweet, caramel flavor and levels of aromatic aldehydes; jurema honey has been described with herb and beeswax aroma and the presence of sulfur compounds and ketones; volatile acids associated with acid taste, medicinal taste and clove aroma characterized the velame branco honey. These results demonstrate that the knowledge of the sensory and aroma profile of these honeys can contribute to characterization of its floral and geographical identity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Queen pheromones: The chemical crown governing insect social life

    DEFF Research Database (Denmark)

    Holman, Luke

    2010-01-01

    Group-living species produce signals that alter the behavior and even the physiology of their social partners. Social insects possess especially sophisticated chemical communication systems that govern every aspect of colony life, including the defining feature of eusociality: reproductive division...... of labor. Current evidence hints at the central importance of queen pheromones, but progress has been hindered by the fact that such pheromones have only been isolated in honeybees. In a pair of papers on the ant Lasius niger, we identified and investigated a queen pheromone regulating worker sterility...... with other studies, these results indicate that queen pheromones are honest signals of quality that simultaneously regulate multiple social behaviors....

  5. Inhibition of Pseudogymnoascus destructans growth from conidia and mycelial extension by bacterially produced volatile organic compounds.

    Science.gov (United States)

    Cornelison, Christopher T; Gabriel, Kyle T; Barlament, Courtney; Crow, Sidney A

    2014-02-01

    The recently identified causative agent of white-nose syndrome (WNS), Pseudogymnoascus destructans, has been implicated in the mortality of an estimated 5.5 million North American bats since its initial documentation in 2006 (Frick et al. in Science 329:679-682, 2010). In an effort to identify potential biological and chemical control options for WNS, 6 previously described bacterially produced volatile organic compounds (VOCs) were screened for anti-P. destructans activity. The compounds include decanal; 2-ethyl-1-hexanol; nonanal; benzothiazole; benzaldehyde; andN,N-dimethyloctylamine. P. destructans conidia and mycelial plugs were exposed to the VOCs in a closed air space at 15 and 4 °C and then evaluated for growth inhibition. All VOCs inhibited growth from conidia as well as inhibiting radial mycelial extension, with the greatest effect at 4 °C. Studies of the ecology of fungistatic soils and the natural abundance of the fungistatic VOCs present in these environments suggest a synergistic activity of select VOCs may occur. The evaluation of formulations of two or three VOCs at equivalent concentrations was supportive of synergistic activity in several cases. The identification of bacterially produced VOCs with anti-P. destructans activity indicates disease-suppressive and fungistatic soils as a potentially significant reservoir of biological and chemical control options for WNS and provides wildlife management personnel with tools to combat this devastating disease.

  6. Volatile compounds and some physico-chemical properties of pastırma produced with different nitrate levels

    Directory of Open Access Journals (Sweden)

    Ahmet Akköse

    2017-08-01

    Full Text Available Objective The aim of the study was to evaluate the effects of different nitrate levels (150, 300, 450, and 600 ppm KNO3 on the volatile compounds and some other properties of pastırma. Methods Pastırma samples were produced under the controlled condition and analyses of volatile compounds, and thiobarbituric acid reactive substances (TBARS as an indicator of lipid oxidation, non-protein nitrogenous matter content as an indicator of proteolysis, color and residual nitrite were carried out on the final product. The profile of volatile compounds of pastırma samples was analyzed by gas chromatography/mass spectrometry using a solid phase microextraction. Results Nitrate level had a significant effect on pH value (p<0.05 and a very significant effect on TBARS value (p<0.01. No significant differences were determined in terms of aw value, non-protein nitrogenous substance content, color and residual nitrite between pastırma groups produced by using different nitrate levels. Nitrate level had a significant (p<0.05 or a very significant (p<0.01 effect on some volatile compounds. It was determined that the amounts and counts of volatile compounds were lower in the 450 and especially 600 ppm nitrate levels than 150 and 300 ppm nitrate levels (p<0.05. While the use of 600 ppm nitrate did not cause an increase in residual nitrite levels, the use of 150 ppm nitrate did not negatively affect the color of pastırma. However, the levels of volatile compounds decreased with an increasing level of nitrate. Conclusion The use of 600 ppm nitrate is not a risk in terms of residual nitrite in pastırma produced under controlled condition, however, this level is not suitable due to decrease in the amount of volatile compounds.

  7. Moth sex pheromone receptors and deceitful parapheromones.

    Directory of Open Access Journals (Sweden)

    Pingxi Xu

    Full Text Available The insect's olfactory system is so selective that male moths, for example, can discriminate female-produced sex pheromones from compounds with minimal structural modifications. Yet, there is an exception for this "lock-and-key" tight selectivity. Formate analogs can be used as replacement for less chemically stable, long-chain aldehyde pheromones, because male moths respond physiologically and behaviorally to these parapheromones. However, it remained hitherto unknown how formate analogs interact with aldehyde-sensitive odorant receptors (ORs. Neuronal responses to semiochemicals were investigated with single sensillum recordings. Odorant receptors (ORs were cloned using degenerate primers, and tested with the Xenopus oocyte expression system. Quality, relative quantity, and purity of samples were evaluated by gas chromatography and gas chromatography-mass spectrometry. We identified olfactory receptor neurons (ORNs housed in trichoid sensilla on the antennae of male navel orangeworm that responded equally to the main constituent of the sex pheromone, (11Z,13Z-hexadecadienal (Z11Z13-16Ald, and its formate analog, (9Z,11Z-tetradecen-1-yl formate (Z9Z11-14OFor. We cloned an odorant receptor co-receptor (Orco and aldehyde-sensitive ORs from the navel orangeworm, one of which (AtraOR1 was expressed specifically in male antennae. AtraOR1•AtraOrco-expressing oocytes responded mainly to Z11Z13-16Ald, with moderate sensitivity to another component of the sex pheromone, (11Z,13Z-hexadecadien-1-ol. Surprisingly, this receptor was more sensitive to the related formate than to the natural sex pheromone. A pheromone receptor from Heliothis virescens, HR13 ( = HvirOR13 showed a similar profile, with stronger responses elicited by a formate analog than to the natural sex pheromone, (11Z-hexadecenal thus suggesting this might be a common feature of moth pheromone receptors.

  8. Analysis of the Agrotis segetum pheromone gland transcriptome in the light of sex pheromone biosynthesis.

    Science.gov (United States)

    Ding, Bao-Jian; Löfstedt, Christer

    2015-09-18

    Moths rely heavily on pheromone communication for mate finding. The pheromone components of most moths are modified from the products of normal fatty acid metabolism by a set of tissue-specific enzymes. The turnip moth, Agrotis segetum uses a series of homologous fatty-alcohol acetate esters ((Z)-5-decenyl, (Z)-7-dodecenyl, and (Z)-9 tetradecenyl acetate) as its sex pheromone components. The ratio of the components differs between populations, making this species an interesting subject for studies of the enzymes involved in the biosynthetic pathway and their influence on sex pheromone variation. Illumina sequencing and comparative analysis of the transcriptomes of the pheromone gland and abdominal epidermal tissue, enabled us to identify genes coding for putative key enzymes involved in the pheromone biosynthetic pathway, such as fatty acid synthase, β-oxidation enzymes, fatty-acyl desaturases (FAD), fatty-acyl reductases (FAR), and acetyltransferases. We functionally assayed the previously identified ∆11-desaturase [GenBank: ES583599, JX679209] and FAR [GenBank: JX679210] and candidate acetyltransferases (34 genes) by heterologous expression in yeast. The functional assay confirmed that the ∆11-desaturase interacts with palmitate and produces (Z)-11-hexadecenoate, which is the common unsaturated precursor of three homologous pheromone component acetates produced by subsequent chain-shortening, reduction and acetylation. Much lower, but still visible, activity on 14C and 12C saturated acids may account for minor pheromone compounds previously observed in the pheromone gland. The FAR characterized can operate on various unsaturated fatty acids that are the immediate acyl precursors of the different A. segetum pheromone components. None of the putative acetyltransferases that we expressed heterologously did acetylate any of the fatty alcohols tested as substrates. The massive sequencing technology generates enormous amounts of candidate genes potentially

  9. Phase change events of volatile liquid perfluorocarbon contrast agents produce unique acoustic signatures

    International Nuclear Information System (INIS)

    Sheeran, Paul S; Dayton, Paul A; Matsunaga, Terry O

    2014-01-01

    Phase-change contrast agents (PCCAs) provide a dynamic platform to approach problems in medical ultrasound (US). Upon US-mediated activation, the liquid core vaporizes and expands to produce a gas bubble ideal for US imaging and therapy. In this study, we demonstrate through high-speed video microscopy and US interrogation that PCCAs composed of highly volatile perfluorocarbons (PFCs) exhibit unique acoustic behavior that can be detected and differentiated from standard microbubble contrast agents. Experimental results show that when activated with short pulses PCCAs will over-expand and undergo unforced radial oscillation while settling to a final bubble diameter. The size-dependent oscillation phenomenon generates a unique acoustic signal that can be passively detected in both time and frequency domain using confocal piston transducers with an ‘activate high’ (8 MHz, 2 cycles), ‘listen low’ (1 MHz) scheme. Results show that the magnitude of the acoustic ‘signature’ increases as PFC boiling point decreases. By using a band-limited spectral processing technique, the droplet signals can be isolated from controls and used to build experimental relationships between concentration and vaporization pressure. The techniques shown here may be useful for physical studies as well as development of droplet-specific imaging techniques. (paper)

  10. Pheromone gland development and pheromone production in lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae).

    Science.gov (United States)

    Spiegel, Carolina N; Batista-Pereira, Luciane G; Bretas, Jorge A C; Eiras, Alvaro E; Hooper, Antony M; Peixoto, Alexandre A; Soares, Maurilio J

    2011-05-01

    The sand fly Lutzomyia longipalpis (Lutz & Neiva) (Diptera: Psychodidae: Phlebotominae) is the main vector of American visceral leishmaniasis. Adult males produce a terpenoid sex pheromone that in some cases also acts as male aggregation pheromone. We have analyzed the correlation between male pheromone production levels and pheromone gland cell morphogenesis after adult emergence from pupae. The abdominal tergites of L. longipalpis males were dissected and fixed in glutaraldehyde for transmission electron microscopy, or the pheromone was extracted in analytical grade hexane. Pheromone chemical analysis was carried out at 3- to 6-h intervals during the first 24 h after emergence and continued daily until the seventh day. All extracts were analyzed by gas chromatography. For the morphological analysis, we used insects collected at 0-6, 9-12, 12-14, and 96 h after emergence. Ultrastructural data from 0- to 6-h-old adult males revealed smaller pheromone gland cells with small microvilli at the end apparatus. Lipid droplets and peroxisomes were absent or very rare, but a large number of mitochondria could be seen. Lipid droplets started to appear in the gland cells cytoplasm approximately 9 h after adult emergence, and their number and size increased with age, together with the presence of several peroxisomes, suggesting a role for these organelles in pheromone biosynthesis. At 12-15 h after emergence, the lipid droplets were mainly distributed near the microvilli but were smaller than those in mature older males (4 d old). Pheromone biosynthesis started around 12 h after emergence and increased continuously during the first 3 d, stabilizing thereafter, coinciding with the period when males are more able to attract females.

  11. Volatile-organic molecular characterization of shale-oil produced water from the Permian Basin.

    Science.gov (United States)

    Khan, Naima A; Engle, Mark; Dungan, Barry; Holguin, F Omar; Xu, Pei; Carroll, Kenneth C

    2016-04-01

    Growth in unconventional oil and gas has spurred concerns on environmental impact and interest in beneficial uses of produced water (PW), especially in arid regions such as the Permian Basin, the largest U.S. tight-oil producer. To evaluate environmental impact, treatment, and reuse potential, there is a need to characterize the compositional variability of PW. Although hydraulic fracturing has caused a significant increase in shale-oil production, there are no high-resolution organic composition data for the shale-oil PW from the Permian Basin or other shale-oil plays (Eagle Ford, Bakken, etc.). PW was collected from shale-oil wells in the Midland sub-basin of the Permian Basin. Molecular characterization was conducted using high-resolution solid phase micro extraction gas chromatography time-of-flight mass spectrometry. Approximately 1400 compounds were identified, and 327 compounds had a >70% library match. PW contained alkane, cyclohexane, cyclopentane, BTEX (benzene, toluene, ethylbenzene, and xylene), alkyl benzenes, propyl-benzene, and naphthalene. PW also contained heteroatomic compounds containing nitrogen, oxygen, and sulfur. 3D van Krevelen and double bond equivalence versus carbon number analyses were used to evaluate molecular variability. Source composition, as well as solubility, controlled the distribution of volatile compounds found in shale-oil PW. The salinity also increased with depth, ranging from 105 to 162 g/L total dissolved solids. These data fill a gap for shale-oil PW composition, the associated petroleomics plots provide a fingerprinting framework, and the results for the Permian shale-oil PW suggest that partial treatment of suspended solids and organics would support some beneficial uses such as onsite reuse and bio-energy production. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Microbial cycling of isoprene, the most abundantly produced biological volatile organic compound on Earth.

    Science.gov (United States)

    McGenity, Terry J; Crombie, Andrew T; Murrell, J Colin

    2018-04-01

    Isoprene (2-methyl-1,3-butadiene), the most abundantly produced biogenic volatile organic compound (BVOC) on Earth, is highly reactive and can have diverse and often detrimental atmospheric effects, which impact on climate and health. Most isoprene is produced by terrestrial plants, but (micro)algal production is important in aquatic environments, and the relative bacterial contribution remains unknown. Soils are a sink for isoprene, and bacteria that can use isoprene as a carbon and energy source have been cultivated and also identified using cultivation-independent methods from soils, leaves and coastal/marine environments. Bacteria belonging to the Actinobacteria are most frequently isolated and identified, and Proteobacteria have also been shown to degrade isoprene. In the freshwater-sediment isolate, Rhodococcus strain AD45, initial oxidation of isoprene to 1,2-epoxy-isoprene is catalyzed by a multicomponent isoprene monooxygenase encoded by the genes isoABCDEF. The resultant epoxide is converted to a glutathione conjugate by a glutathione S-transferase encoded by isoI, and further degraded by enzymes encoded by isoGHJ. Genome sequence analysis of actinobacterial isolates belonging to the genera Rhodococcus, Mycobacterium and Gordonia has revealed that isoABCDEF and isoGHIJ are linked in an operon, either on a plasmid or the chromosome. In Rhodococcus strain AD45 both isoprene and epoxy-isoprene induce a high level of transcription of 22 contiguous genes, including isoABCDEF and isoGHIJ. Sequence analysis of the isoA gene, encoding the large subunit of the oxygenase component of isoprene monooxygenase, from isolates has facilitated the development of PCR primers that are proving valuable in investigating the ecology of uncultivated isoprene-degrading bacteria.

  13. Volatile-organic molecular characterization of shale-oil produced water from the Permian Basin

    Science.gov (United States)

    Khan, Naima A.; Engle, Mark A.; Dungan, Barry; Holguin, F. Omar; Xu, Pei; Carroll, Kenneth C.

    2016-01-01

    Growth in unconventional oil and gas has spurred concerns on environmental impact and interest in beneficial uses of produced water (PW), especially in arid regions such as the Permian Basin, the largest U.S. tight-oil producer. To evaluate environmental impact, treatment, and reuse potential, there is a need to characterize the compositional variability of PW. Although hydraulic fracturing has caused a significant increase in shale-oil production, there are no high-resolution organic composition data for the shale-oil PW from the Permian Basin or other shale-oil plays (Eagle Ford, Bakken, etc.). PW was collected from shale-oil wells in the Midland sub-basin of the Permian Basin. Molecular characterization was conducted using high-resolution solid phase micro extraction gas chromatography time-of-flight mass spectrometry. Approximately 1400 compounds were identified, and 327 compounds had a >70% library match. PW contained alkane, cyclohexane, cyclopentane, BTEX (benzene, toluene, ethylbenzene, and xylene), alkyl benzenes, propyl-benzene, and naphthalene. PW also contained heteroatomic compounds containing nitrogen, oxygen, and sulfur. 3D van Krevelen and double bond equivalence versus carbon number analyses were used to evaluate molecular variability. Source composition, as well as solubility, controlled the distribution of volatile compounds found in shale-oil PW. The salinity also increased with depth, ranging from 105 to 162 g/L total dissolved solids. These data fill a gap for shale-oil PW composition, the associated petroleomics plots provide a fingerprinting framework, and the results for the Permian shale-oil PW suggest that partial treatment of suspended solids and organics would support some beneficial uses such as onsite reuse and bio-energy production.

  14. Isolation of a pyrazine alarm pheromone component from the fire ant, Solenopsis invicta.

    Science.gov (United States)

    Vander Meer, Robert K; Preston, Catherine A; Choi, Man-Yeon

    2010-02-01

    Alarm pheromones in social insects are an essential part of a complex of pheromone interactions that contribute to the maintenance of colony integrity and sociality. The alarm pheromones of ants were among the first examples of animal pheromones identified, primarily because of the large amount of chemical produced and the distinctive responses of ants to the pheromone. However, the alarm pheromone of the fire ant, Solenopsis invicta, eluded identification for over four decades. We identified 2-ethyl-3,6-dimethylpyrazine as an alarm pheromone component of S. invicta. Worker fire ants detect the pyrazine alarm pheromone at 30 pg/ml, which is comparable to alarm pheromone sensitivities reported for other ant species. The source of this alarm pheromone are the mandibular glands, which, in fire ants, are not well developed and contain only about 300 pg of the compound, much less than the microgram quantities of alarm pheromones reported for several other ant species. Female and male sexuals and workers produce the pyrazine, which suggests that it may be involved in fire ant mating flight initiation, as well as the typical worker alarm response. This is the first report of 2-ethyl-3,6-dimethylpyrazine from a Solenopsis species and the first example of this alkaloid functioning as an alarm pheromone.

  15. Determination of volatiles produced during radiation processing in food and medicinal herbs

    International Nuclear Information System (INIS)

    Salum, Debora Christina

    2008-01-01

    In order to protect food from pathogenic microorganisms as well as to increase its shelf life while keeping sensorial properties (e.g. odor and taste), once the latter are one of the main properties required by spice buyers, it is necessary to analyze volatile formation from irradiation of medicinal and food herbs. The aim of the present study was to analyze volatile formation from Co irradiation of Laurus Cinnamomum, Piper Nigrum, Origanum Vulgare and Myristica Fragans. Possible changes on the odor of these herbs are evaluated by characterizing different radiation doses and effects on sensorial properties in order to allow better application of irradiation technology. l he samples have been irradiated in plastic packages by making use of a 60 Co Gamma irradiator. Irradiation doses of 0, 5, 10, 15, 20 and 25kGy have been tested. For the analysis of the samples, SPME has been applied, while for the analysis of volatile compounds, CG/MS. Spice irradiation has promoted mostly decrease in volatile compounds when doses of 5, 10, 15, 20 and 25kGy were used. For Laurus cinnamomum, the irradiation decreased volatile by nearly 56% and 89.5% respectively, comparing to volatile from a sample which has not been previously irradiated. Differently from other spices analyzed, irradiation on Myristica Fragans has increased volatile compounds except for 4-terpineol. The miristicine (toxic substance when in large quantities, commonly mentioned as narcotic) has increased by nearly 80%. For Origanum Vulgare and Piper Nigrum, significant decrease in volatile compounds have been found, mainly when it comes to 25 kGy irradiation. In general, results indicate loss of sensorial quality of spices. (author)

  16. Resposta de Cosmopolites sordidus (Germar (Coleoptera, Curculionidae aos voláteis da planta hospedeira e de adultos coespecíficos em olfatômetro Response of Cosmopolites sordidus (Germar (Coleoptera, Curculionidae to host volatiles and conspecific in olfactometer

    Directory of Open Access Journals (Sweden)

    Fernando A. C. de Mendonça

    1999-01-01

    Full Text Available The response of Cosmopolites sordidus (Germar, 1824 to the volatiles of its host banana plant (Musa paradisiaca cv. Prata and conspecific adults was studied. In olfactometer, the attraction of males and females of C. sordidus to rhizome and pseudotem of the banana, fresh or rotting, was observed. The results suggested that the aggregation pheromone is produced by males and that it attracts both sexes, and that there is another pheromone produced by females which attracts males only. The results also suggest that the females are the first responsible for the aggregation of the species, but the male pheromone is mainly responsible for the mass aggregation. Nevertheless, the aggregation phenomenon is a consequence of the mutual action of both pheromones plus the kairomones produced by the banana plant.

  17. Diversity and functions of volatile organic compounds produced by Streptomyces from a disease-suppressive soil.

    Science.gov (United States)

    Cordovez, Viviane; Carrion, Victor J; Etalo, Desalegn W; Mumm, Roland; Zhu, Hua; van Wezel, Gilles P; Raaijmakers, Jos M

    2015-01-01

    In disease-suppressive soils, plants are protected from infections by specific root pathogens due to the antagonistic activities of soil and rhizosphere microorganisms. For most disease-suppressive soils, however, the microorganisms and mechanisms involved in pathogen control are largely unknown. Our recent studies identified Actinobacteria as the most dynamic phylum in a soil suppressive to the fungal root pathogen Rhizoctonia solani. Here we isolated and characterized 300 isolates of rhizospheric Actinobacteria from the Rhizoctonia-suppressive soil. Streptomyces species were the most abundant, representing approximately 70% of the isolates. Streptomyces are renowned for the production of an exceptionally large number of secondary metabolites, including volatile organic compounds (VOCs). VOC profiling of 12 representative Streptomyces isolates by SPME-GC-MS allowed a more refined phylogenetic delineation of the Streptomyces isolates than the sequencing of 16S rRNA and the house-keeping genes atpD and recA only. VOCs of several Streptomyces isolates inhibited hyphal growth of R. solani and significantly enhanced plant shoot and root biomass. Coupling of Streptomyces VOC profiles with their effects on fungal growth, pointed to VOCs potentially involved in antifungal activity. Subsequent assays with five synthetic analogs of the identified VOCs showed that methyl 2-methylpentanoate, 1,3,5-trichloro-2-methoxy benzene and the VOCs mixture have antifungal activity. In conclusion, our results point to a potential role of VOC-producing Streptomyces in disease suppressive soils and show that VOC profiling of rhizospheric Streptomyces can be used as a complementary identification tool to construct strain-specific metabolic signatures.

  18. Diversity and functions of volatile organic compounds produced by Streptomyces from a disease-suppressive soil

    Directory of Open Access Journals (Sweden)

    Viviane eCordovez

    2015-10-01

    Full Text Available In disease-suppressive soils, plants are protected from infections by specific root pathogens due to the antagonistic activities of soil and rhizosphere microorganisms. For most disease-suppressive soils, however, the microorganisms and mechanisms involved in pathogen control are largely unknown. Our recent studies identified Actinobacteria as the most dynamic phylum in a soil suppressive to the fungal root pathogen Rhizoctonia solani. Here we isolated and characterized 300 isolates of rhizospheric Actinobacteria from the Rhizoctonia-suppressive soil. Streptomyces species were the most abundant, representing approximately 70% of the isolates. Streptomyces are renowned for the production of an exceptionally large number of secondary metabolites, including volatile organic compounds (VOCs. VOC profiling of 12 representative Streptomyces isolates by SPME-GC-MS allowed a more refined phylogenetic delineation of the Streptomyces isolates than the sequencing of 16S rRNA and the house-keeping genes atpD and recA only. VOCs of several Streptomyces isolates inhibited hyphal growth of R. solani and significantly enhanced plant shoot and root biomass. Coupling of Streptomyces VOC profiles with their effects on fungal growth, pointed to VOCs potentially involved in antifungal activity. Subsequent assays with five synthetic analogues of the identified VOCs showed that methyl 2-methylpentanoate, 1,3,5-trichloro-2-methoxy benzene and the VOCs mixture have antifungal activity. In conclusion, our results point to a potential role of VOC-producing Streptomyces in disease suppressive soils and show that VOC profiling of rhizospheric Streptomyces can be used as a complementary identification tool to construct strain-specific metabolic signatures.

  19. Peripheral, central and behavioral responses to the cuticular pheromone bouquet in Drosophila melanogaster males.

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Inoshita

    Full Text Available Pheromonal communication is crucial with regard to mate choice in many animals including insects. Drosophila melanogaster flies produce a pheromonal bouquet with many cuticular hydrocarbons some of which diverge between the sexes and differently affect male courtship behavior. Cuticular pheromones have a relatively high weight and are thought to be -- mostly but not only -- detected by gustatory contact. However, the response of the peripheral and central gustatory systems to these substances remains poorly explored. We measured the effect induced by pheromonal cuticular mixtures on (i the electrophysiological response of peripheral gustatory receptor neurons, (ii the calcium variation in brain centers receiving these gustatory inputs and (iii the behavioral reaction induced in control males and in mutant desat1 males, which show abnormal pheromone production and perception. While male and female pheromones induced inhibitory-like effects on taste receptor neurons, the contact of male pheromones on male fore-tarsi elicits a long-lasting response of higher intensity in the dedicated gustatory brain center. We found that the behavior of control males was more strongly inhibited by male pheromones than by female pheromones, but this difference disappeared in anosmic males. Mutant desat1 males showed an increased sensitivity of their peripheral gustatory neurons to contact pheromones and a behavioral incapacity to discriminate sex pheromones. Together our data indicate that cuticular hydrocarbons induce long-lasting inhibitory effects on the relevant taste pathway which may interact with the olfactory pathway to modulate pheromonal perception.

  20. A Predictive Model for Yeast Cell Polarization in Pheromone Gradients.

    Science.gov (United States)

    Muller, Nicolas; Piel, Matthieu; Calvez, Vincent; Voituriez, Raphaël; Gonçalves-Sá, Joana; Guo, Chin-Lin; Jiang, Xingyu; Murray, Andrew; Meunier, Nicolas

    2016-04-01

    Budding yeast cells exist in two mating types, a and α, which use peptide pheromones to communicate with each other during mating. Mating depends on the ability of cells to polarize up pheromone gradients, but cells also respond to spatially uniform fields of pheromone by polarizing along a single axis. We used quantitative measurements of the response of a cells to α-factor to produce a predictive model of yeast polarization towards a pheromone gradient. We found that cells make a sharp transition between budding cycles and mating induced polarization and that they detect pheromone gradients accurately only over a narrow range of pheromone concentrations corresponding to this transition. We fit all the parameters of the mathematical model by using quantitative data on spontaneous polarization in uniform pheromone concentration. Once these parameters have been computed, and without any further fit, our model quantitatively predicts the yeast cell response to pheromone gradient providing an important step toward understanding how cells communicate with each other.

  1. Peptide pheromone signaling in Streptococcus and Enterococcus

    Science.gov (United States)

    Cook, Laura C.; Federle, Michael J.

    2014-01-01

    Intercellular chemical signaling in bacteria, commonly referred to as quorum sensing (QS), relies on the production and detection of compounds known as pheromones to elicit coordinated responses among members of a community. Pheromones produced by Gram-positive bacteria are comprised of small peptides. Based on both peptide structure and sensory system architectures, Gram-positive bacterial signaling pathways may be classified into one of four groups with a defining hallmark: cyclical peptides of the Agr type, peptides that contain Gly-Gly processing motifs, sensory systems of the RNPP family, or the recently characterized Rgg-like regulatory family. The recent discovery that Rgg family members respond to peptide pheromones increases substantially the number of species in which QS is likely a key regulatory component. These pathways control a variety of fundamental behaviors including conjugation, natural competence for transformation, biofilm development, and virulence factor regulation. Overlapping QS pathways found in multiple species and pathways that utilize conserved peptide pheromones provide opportunities for interspecies communication. Here we review pheromone signaling identified in the genera Enterococcus and Streptococcus, providing examples of all four types of pathways. PMID:24118108

  2. Controlled release of insect sex pheromones from paraffin wax and emulsions.

    Science.gov (United States)

    Atterholt, C A; Delwiche, M J; Rice, R E; Krochta, J M

    1999-02-22

    Paraffin wax and aqueous paraffin emulsions can be used as controlled release carriers for insect sex pheromones for mating disruption of orchard pests. Paraffin can be applied at ambient temperature as an aqueous emulsion, adheres to tree bark or foliage, releases pheromone for an extended period of time, and will slowly erode from bark and biodegrade in soil. Pheromone emulsions can be applied with simple spray equipment. Pheromone release-rates from paraffin were measured in laboratory flow-cell experiments. Pheromone was trapped from an air stream with an adsorbent, eluted periodically, and quantified by gas chromatography. Pheromone release from paraffin was partition-controlled, providing a constant (zero-order) release rate. A typical paraffin emulsion consisted of 30% paraffin, 4% pheromone, 4% soy oil, 1% vitamin E, 2% emulsifier, and the balance water. Soy oil and vitamin E acted as volatility suppressants. A constant release of oriental fruit moth pheromone from paraffin emulsions was observed in the laboratory for more than 100 days at 27 degreesC, with release-rates ranging from 0.4 to 2 mg/day, depending on the concentration and surface area of the dried emulsion. The use of paraffin emulsions is a viable method for direct application of insect pheromones for mating disruption. Sprayable formulations can be designed to release insect pheromones to the environment at a rate necessary for insect control by mating disruption. At temperatures below 38 degreesC, zero-order release was observed. At 38 degreesC and higher, pheromone oxidation occurred. A partition-controlled release mechanism was supported by a zero-order pheromone release-rate, low air/wax partition coefficients, and pheromone solubility in paraffin.

  3. Silo-stored pistachios at varying humidity levels produce distinct volatile biomarkers

    Science.gov (United States)

    Aflatoxin contamination in California tree nuts results in millions of dollars of lost product annually. The current method for detection of aflatoxin is destructive, expensive and time-intensive. Previous studies have demonstrated that volatile profiles of fungal-contaminated tissues are different ...

  4. Profiling of volatile organic compounds produced by clinical Aspergillus isolates using gas chromatography-mass spectrometry

    NARCIS (Netherlands)

    Gerritsen, M G; Brinkman, P; Escobar Salazar, Natalia; Bos, L D; de Heer, K; Meijer, M; Janssen, H-G; de Cock, H; Wösten, H A B; Visser, C.E.; van Oers, M H J; Sterk, P J

    Volatile organic compounds (VOCs) in exhaled breath may identify the presence of invasive pulmonary aspergillosis. We aimed to detect VOC profiles emitted by in vitro cultured, clinical Aspergillus isolates using gas chromatography-mass spectrometry (GC-MS). Three clinical Aspergillus isolates and a

  5. Profiling of volatile organic compounds produced by clinical Aspergillus isolates using gas chromatography-mass spectrometry

    NARCIS (Netherlands)

    Gerritsen, M. G.; Brinkman, P.; Escobar, N.; Bos, L. D.; de Heer, K.; Meijer, M.; Janssen, H.-G.; de Cock, H.; Wösten, H. A. B.; Visser, C. E.; van Oers, M. H. J.; Sterk, P. J.

    2018-01-01

    Volatile organic compounds (VOCs) in exhaled breath may identify the presence of invasive pulmonary aspergillosis. We aimed to detect VOC profiles emitted by in vitro cultured, clinical Aspergillus isolates using gas chromatography-mass spectrometry (GC-MS). Three clinical Aspergillus isolates and a

  6. Analyses of volatiles produced by the African fruit fly species complex (Diptera, Tephritidae)

    Czech Academy of Sciences Publication Activity Database

    Břízová, Radka; Vaníčková, Lucie; Faťarová, M.; Ekesi, S.; Hoskovec, Michal; Kalinová, Blanka

    -, č. 540 (2015), s. 385-404 ISSN 1313-2989 Institutional support: RVO:61388963 Keywords : Ceratitis FAR complex * chemotaxonomy * male and female-borne volatiles * GCxGC-TOFMS * GC-EAD Subject RIV: EG - Zoology Impact factor: 0.938, year: 2015 http://zookeys.pensoft.net/articles.php?id=6223

  7. Unexpected plant odor responses in a moth pheromone system

    Directory of Open Access Journals (Sweden)

    Angéla eRouyar

    2015-05-01

    Full Text Available Male moths rely on olfactory cues to find females for reproduction. Males also use volatile plant compounds (VPCs to find food sources and might use host-plant odor cues to identify the habitat of calling females. Both the sex pheromone released by conspecific females and VPCs trigger well-described oriented flight behavior towards the odor source. Whereas detection and central processing of pheromones and VPCs have been thought for a long time to be highly separated from each other, recent studies have shown that interactions of both types of odors occur already early at the periphery of the olfactory pathway. Here we show that detection and early processing of VPCs and pheromone can overlap between the two sub-systems. Using complementary approaches, i.e. single-sensillum recording of olfactory receptor neurons, in vivo calcium imaging in the antennal lobe, intracellular recordings of neurons in the macroglomerular complex (MGC and flight tracking in a wind tunnel, we show that some plant odorants alone, such as heptanal, activate the pheromone-specific pathway in male Agrotis ipsilon at peripheral and central levels. To our knowledge, this is the first report of a plant odorant with no chemical similarity to the molecular structure of the pheromone, acting as a partial agonist of a moth sex pheromone.

  8. Refining the dual olfactory hypothesis: pheromone reward and odour experience.

    Science.gov (United States)

    Martínez-García, Fernando; Martínez-Ricós, Joana; Agustín-Pavón, Carmen; Martínez-Hernández, Jose; Novejarque, Amparo; Lanuza, Enrique

    2009-06-25

    In rodents, sexual advertisement and gender recognition are mostly (if not exclusively) mediated by chemosignals. Specifically, there is ample evidence indicating that female mice are 'innately' attracted by male sexual pheromones that have critical non-volatile components and are detected by the vomeronasal organ. These pheromones can only get access to the vomeronasal organ by active pumping mechanisms that require close contact with the source of the stimulus (e.g. urine marks) during chemoinvestigation. We have hypothesised that male sexual pheromones are rewarding to female mice. Indeed, male-soiled bedding can be used as a reinforcer to induce conditioned place preference, provided contact with the bedding is allowed. The neural mechanisms of pheromone reward seem, however, different from those employed by other natural reinforcers, such as the sweetness or postingestive effects of sucrose. In contrast to vomeronasal-detected male sexual pheromones, male-derived olfactory stimuli (volatiles) are not intrinsically attractive to female mice. However, after repeated exposure to male-soiled bedding, intact female mice develop an acquired preference for male odours. On the contrary, in females whose accessory olfactory bulbs have been lesioned, exposure to male-soiled bedding induces aversion to male odorants. These considerations, together with data on the different properties of olfactory and vomeronasal receptors, lead us to make a proposal for the complementary roles that the olfactory and vomeronasal systems play in intersexual attraction and in other forms of intra- or inter-species communication.

  9. Measurement of the volatility and glass transition temperatures of glasses produced during the DWPF startup test program

    International Nuclear Information System (INIS)

    Marra, J.C.; Harbour, J.R.

    1995-01-01

    The Defense Waste Processing Facility (DWPF) will immobilize high-level radioactive waste currently stored in underground tanks at the Savannah River Site by incorporating the waste into a glass matrix. The molten waste glass will be poured into stainless steel canisters which will be welded shut to produce the final waste form. One specification requires that any volatiles produced as a result of accidentally heating the waste glass to the glass transition temperature be identified. Glass samples from five melter campaigns, run as part of the DWPF Startup Test Program, were analyzed to determine glass transition temperatures and to examine the volatilization (by weight loss). Glass transition temperatures (T g ) for the glasses, determined by differential scanning calorimetry (DSC), ranged between 445 C and 474 C. Thermogravimetric analysis (TGA) scans showed that no overall weight loss occurred in any of the glass samples when heated to 500 C. Therefore, no volatility will occur in the final glass product when heated up to 500 C

  10. Collection of pheromone from atmosphere surrounding boll weevils,Anthonomus grandis.

    Science.gov (United States)

    Chang, J F; Benedict, J H; Payne, T L; Camp, B J; Vinson, S B

    1989-02-01

    An effluvial method was developed to collect the pheromone, grandlure from actively calling male boll weevils,Anthonomus grandis Boheman. The adsorbant, Porapak Q (ethylvinylbenzene-divinylbenzene), was utilized to trap and concentrate the pheromone. Captured pheromone was desorbed from columns packed with Porapak Q by elution withn-pentane and quantified by capillary column gas-liquid chromatography. In recovery studies with known amounts of synthetic grandlure, we found that the amount of each pheromone component collected was a function of collection duration, elution volume, and initial concentration. This effluvial method was capable of recovering as much as 94.9% of a known quantity (80 μg) of grandlure. The chromatograms were free of extraneous peaks. In studies of insect-produced pheromone, the effluvial method was used to collect pheromone from the air space surrounding male boll weevils as they fed on flower buds from CAMD-E cotton. The quantity and quality of boll-weevil-produced pheromone was determined for days 6, 8, 10, 11, 12, 13, and 14 of boll weevil adulthood. The maximum quantity of natural pheromone was produced on day 13 (4.2 μg/weevil) with a pheromone component ratio of 2.41∶2.29∶0.95∶1 for components I, II, III, and IV, respectively. The effluvial method described in this report is an efficient method to collect and quantify boll weevil pheromone from the atmosphere surrounding actively calling insects. Other applications of this method are suggested.

  11. Diffusible and Volatile Antifungal Compounds Produced by an Antagonistic Bacillus velezensis G341 against Various Phytopathogenic Fungi

    Directory of Open Access Journals (Sweden)

    Seong Mi Lim

    2017-10-01

    Full Text Available The aim of this study was to identify volatile and agar-diffusible antifungal metabolites produced by Bacillus sp. G341 with strong antifungal activity against various phytopathogenic fungi. Strain G341 isolated from four-year-old roots of Korean ginseng with rot symptoms was identified as Bacillus velezensis based on 16S rDNA and gyrA sequences. Strain G341 inhibited mycelial growth of all phytopathogenic fungi tested. In vivo experiment results revealed that n-butanol extract of fermentation broth effectively controlled the development of rice sheath blight, tomato gray mold, tomato late blight, wheat leaf rust, barley powdery mildew, and red pepper anthracnose. Two antifungal compounds were isolated from strain G341 and identified as bacillomycin L and fengycin A by MS/MS analysis. Moreover, volatile compounds emitted from strain G341 were found to be able to inhibit mycelial growth of various phytopathogenic fungi. Based on volatile compound profiles of strain G341 obtained through headspace collection and analysis on GC-MS, dimethylsulfoxide, 1-butanol, and 3-hydroxy-2-butanone (acetoin were identified. Taken together, these results suggest that B. valezensis G341 can be used as a biocontrol agent for various plant diseases caused by phytopathogenic fungi.

  12. Diffusible and Volatile Antifungal Compounds Produced by an Antagonistic Bacillus velezensis G341 against Various Phytopathogenic Fungi.

    Science.gov (United States)

    Lim, Seong Mi; Yoon, Mi-Young; Choi, Gyung Ja; Choi, Yong Ho; Jang, Kyoung Soo; Shin, Teak Soo; Park, Hae Woong; Yu, Nan Hee; Kim, Young Ho; Kim, Jin-Cheol

    2017-10-01

    The aim of this study was to identify volatile and agar-diffusible antifungal metabolites produced by Bacillus sp. G341 with strong antifungal activity against various phytopathogenic fungi. Strain G341 isolated from four-year-old roots of Korean ginseng with rot symptoms was identified as Bacillus velezensis based on 16S rDNA and gyrA sequences. Strain G341 inhibited mycelial growth of all phytopathogenic fungi tested. In vivo experiment results revealed that n -butanol extract of fermentation broth effectively controlled the development of rice sheath blight, tomato gray mold, tomato late blight, wheat leaf rust, barley powdery mildew, and red pepper anthracnose. Two antifungal compounds were isolated from strain G341 and identified as bacillomycin L and fengycin A by MS/MS analysis. Moreover, volatile compounds emitted from strain G341 were found to be able to inhibit mycelial growth of various phytopathogenic fungi. Based on volatile compound profiles of strain G341 obtained through headspace collection and analysis on GC-MS, dimethylsulfoxide, 1-butanol, and 3-hydroxy-2-butanone (acetoin) were identified. Taken together, these results suggest that B. valezensis G341 can be used as a biocontrol agent for various plant diseases caused by phytopathogenic fungi.

  13. Alarm Pheromone Activity of Nymph-specific Geraniol in Chrysanthemum Lace Bug Corythucha marmorata against Adults and Nymphs.

    Science.gov (United States)

    Watanabe, Kisaki; Shimizu, Nobuhiro

    2015-09-01

    The exotic insect pest Corythucha marmorata (Uhler) is increasingly spreading in Japan using the weed Solidago canadensis L. as a major host plant. The nymphs form colonies on the backs of leaves where they crowd together; however, aggregation does not occur in the adults. When an individual nymph is crushed using a needle tip and further the needle tip covered with the nymph's bodily fluids is moved slowly toward the center of the crowd, the surrounding nymphs display an escape behavior and their aggregation is disrupted. We detected geraniol as a nymph-specific volatile component. Bioassay results indicated that geraniol was effective as an alarm pheromone on second to fifth instar nymphs. Furthermore, we found that male and female adults responded sensitively to the alarm pheromone produced by nymphs. These results suggest that although the adult insects do not secrete geraniol, they can detect it produced by nymphs, thereby retaining the ability to escape from danger while suppressing the cost of geraniol production. The present study is the first to demonstrate that an alarm pheromone secreted by nymphs is also effective in adults among Tingidae.

  14. Foragers of sympatric Asian honey bee species intercept competitor signals by avoiding benzyl acetate from Apis cerana alarm pheromone.

    Science.gov (United States)

    Wen, Ping; Cheng, Yanan; Qu, Yufeng; Zhang, Hongxia; Li, Jianjun; Bell, Heather; Tan, Ken; Nieh, James

    2017-07-27

    While foraging, animals can form inter- and intraspecific social signalling networks to avoid similar predators. We report here that foragers of different native Asian honey bee species can detect and use a specialized alarm pheromone component, benzyl acetate (BA), to avoid danger. We analysed the volatile alarm pheromone produced by attacked workers of the most abundant native Asian honey bee, Apis cerana and tested the responses of other bee species to these alarm signals. As compared to nest guards, A. cerana foragers produced 3.38 fold higher levels of BA. In foragers, BA and (E)-dec-2-en-1-yl acetate (DA) generated the strongest antennal electrophysiological responses. BA was also the only compound that alerted flying foragers and inhibited A. cerana foraging. BA thereby decreased A. cerana foraging for risky sites. Interestingly, although BA occurs only in trace amounts and is nearly absent in sympatric honeybee species (respectively only 0.07% and 0.44% as much in A. dorsata and A. florea), these floral generalists detected and avoided BA as strongly as they did to their own alarm pheromone on natural inflorescences. These results demonstrate that competing pollinators can take advantage of alarm signal information provided by other species.

  15. Head Space Solid Phase Micro-Extraction (HS - SPME of volatile organic compounds produced by Sporidiobolus salmonicolor (CBS 2636

    Directory of Open Access Journals (Sweden)

    Eunice Valduga

    2010-12-01

    Full Text Available The aim of the present study was the assessment of volatile organic compounds produced by Sporidiobolus salmonicolor (CBS 2636 using methyl and ethyl ricinoleate, ricinoleic acid and castor oil as precursors. The analysis of the volatile organic compounds was carried out using Head Space Solid Phase Micro-Extraction (HS - SPME. Factorial experimental design was used for investigating extraction conditions, verifying stirring rate (0-400 rpm, temperature (25-60 ºC, extraction time (10-30 minutes, and sample volume (2-3 mL. The identification of volatile organic compounds was carried out by Gas Chromatography with Mass Spectrum Detector (GC/MSD. The conditions that resulted in maximum extraction were: 60 ºC, 10 minutes extraction, no stirring, sample volume of 2.0 mL, and addition of saturated KCl (1:10 v/v. In the bio-production of volatile organic compounds the effect of stirring rate (120-200 rpm, temperature (23-33 ºC, pH (4.0-8.0, precursor concentration (0.02-0.1%, mannitol (0-6%, and asparagine concentration (0-0.2% was investigated. The bio-production at 28 ºC, 160 rpm, pH 6,0 and with the addition of 0.02% ricinoleic acid to the medium yielded the highest production of VOCs, identified as 1,4-butanediol, 1,2,2-trimethylciclopropilamine, beta-ionone; 2,3-butanodione, pentanal, tetradecane, 2-isononenal, 4-octen-3-one, propanoic acid, and octadecane.

  16. Pheromone Autodetection: Evidence and Implications

    Science.gov (United States)

    Holdcraft, Robert; Rodriguez-Saona, Cesar; Stelinski, Lukasz L.

    2016-01-01

    Olfactory communication research with insects utilizing sex pheromones has focused on the effects of pheromones on signal receivers. Early pheromone detection studies using the silkworm moth, Bombyx mori L., and Saturniids led to the assumption that emitters, especially females, are unable to detect their own pheromone. Pheromone anosmia, i.e., the inability of females to detect their conspecific sex pheromone, was often assumed, and initially little attention was paid to female behaviors that may result from autodetection, i.e., the ability of females to detect their sex pheromone. Detection of conspecific pheromone plumes from nearby females may provide information to improve chances of mating success and progeny survival. Since the first documented example in 1972, numerous occurrences of autodetection have been observed and verified in field and laboratory studies. We summarize here a significant portion of research relating to autodetection. Electrophysiological and behavioral investigations, as well as expression patterns of proteins involved in pheromone autodetection are included. We discuss problems inherent in defining a boundary between sex and aggregation pheromones considering the occurrence of autodetection, and summarize hypothesized selection pressures favoring autodetection. Importance of including autodetection studies in future work is emphasized by complications arising from a lack of knowledge combined with expanding the use of pheromones in agriculture. PMID:27120623

  17. Components of male aggregation pheromone of strawberry blossom weevil, Anthonomus rubi herbst. (Coleoptera:Curculionidae).

    Science.gov (United States)

    Innocenzi, P J; Hall, D R; Cross, J V

    2001-06-01

    The strawberry blossom weevil, Anthonomus rubi, is a major pest of strawberries in the United Kingdom and continental Europe. As part of a project to develop noninsecticidal control methods, the pheromone system of this species was investigated. Comparison of volatiles produced by field-collected, overwintering individuals of each sex led to identification of three male-specific compounds--(Z)-2-(3,3-dimethylcyclohexylidene)ethanol, (cis)-1-methyl-2-(1-methylethenyl)cyclobutaneethanol, and 2-(1-methylethenyl)-5-methyl-4-hexen-1-ol (lavandulol)--in amounts of 6.1, 1.2, and 0.82 microg/day/ male. The first two compounds are components of the aggregation pheromone of the boll weevil, Anthonomus grandis, grandlure II and grandlure I, respectively. Grandlure I was the (1R,2S)-(+) enantiomer and lavandulol was a single enantiomer, although the absolute configuration was not determined. Trace amounts of the other two grandlure components (Z)-(3,3-dimethylcyclohexylidene)acetaldehyde (grandlure III) and (E)-(3,3-dimethylcyclohexylidene)acetaldehyde (grandlure IV) were also detected. (E,E)-1-(1-Methylethyl)-4-methylene-8-methyl-2,7-cyclo-decadiene (germacrene-D), a known volatile from strawberry plants, Fragaria ananassa, was collected in increased amounts in the presence of pheromone-producing weevils. Male weevils only produced pheromone on F. ananassa and not on scented mayweed, Matracaria recutita, or cow parsley, Anthriscus sylvestris, although these are known food sources. In field trials using various combinations of synthetic grandlures I, II, III, and IV and lavandulol, significantly more weevils were caught in traps baited with blends containing grandlure I and II and lavandulol than in those baited with blends without lavandulol or unbaited controls. Addition of grandlure III and IV had no significant effect on attractiveness. Horizontal sticky traps were found to be more effective than vertical sticky traps or standard boll weevil traps. In mid-season females

  18. Volatile fatty acids influence on the structure of microbial communities producing PHAs

    Directory of Open Access Journals (Sweden)

    Slawomir Ciesielski

    2014-06-01

    Full Text Available Polyhydroxyalkanoates (PHAs can be produced by microorganisms and are a biodegradable alternative to fossil-fuel based plastics. Currently, the focus is on reducing production costs by exploring alternative substrates for PHAs production, and on producing copolymers which are less brittle than monomers. Accordingly, this study used a substrate consisting of wastewater from waste-glycerol fermentation, supplemented with different amounts of acetic and propionic acids. These substrates were used to feed mixed microbial communities enriched from activated sludge in a sequencing batch reactor. A reactor supplemented with 2 mL of acetic acid produced 227.8 mg/L of a homopolymer of hydroxybutyrate (3HB; 4 mL of acetic acid produced 279.8 mg/L 3HB; whereas 4 mL of propionic acid produced 673.0 mg/L of a copolymer of 3HB and 3HV (hydroxyvalerate. Ribosomal Intergenic Spacer Analysis (RISA was used to show the differences between the communities created in the reactors. Thauera species predominated in biomass that produced 3HB; Paracoccus denitrificans in the biomass that produced 3HB-co-3HV. Because P. denitrificans produced the more desirable copolymer, it may be advantageous to promote its growth in PHAs-producing reactors by adding propionate.

  19. The Shewanella algae strain YM8 produces volatiles with strong inhibition activity against Aspergillus pathogens and aflatoxins

    Directory of Open Access Journals (Sweden)

    Andong eGong

    2015-10-01

    Full Text Available Aflatoxigenic Aspergillus fungi and associated aflatoxins are ubiquitous in the production and storage of food/feed commodities. Controlling these pests is a challenge. In this study, the Shewanella algae strain YM8 was found to produce volatiles that have strong antifungal activity against Aspergillus pathogens. Gas chromatography-mass spectrometry profiling revealed 15 volatile organic compounds (VOCs emitted from YM8, of which dimethyl trisulfide was the most abundant. We obtained authentic reference standards for six of the VOCs; these all significantly reduced mycelial growth and conidial germination in Aspergillus; dimethyl trisulfide and 2,4-bis(1,1-dimethylethyl-phenol showed the strongest inhibitory activity. YM8 completely inhibited Aspergillus growth and aflatoxin biosynthesis in maize and peanut samples stored at different water activity levels, and scanning electron microscopy revealed severely damaged conidia and a complete lack of mycelium development and conidiogenesis. YM8 also completely inhibited the growth of eight other agronomically important species of phytopathogenic fungi: A. parasiticus, A. niger, Alternaria alternate, Botrytis cinerea, Fusarium graminearum, Fusarium oxysporum, Monilinia fructicola, and Sclerotinia sclerotiorum. This study demonstrates the susceptibility of Aspergillus and other fungi to VOCs from marine bacteria and indicates a new strategy for effectively controlling these pathogens and the associated mycotoxin production in the field and during storage.

  20. Do pheromones reveal male immunocompetence?

    Science.gov (United States)

    Rantala, Markus J; Jokinen, Ilmari; Kortet, Raine; Vainikka, Anssi; Suhonen, Jukka

    2002-01-01

    Pheromones function not only as mate attractors, but they may also relay important information to prospective mates. It has been shown that vertebrates can distinguish, via olfactory mechanisms, major histocompatibility complex types in their prospective mates. However, whether pheromones can transmit information about immunocompetence is unknown. Here, we show that female mealworm beetles (Tenebrio molitor) prefer pheromones from males with better immunocompetence, indicated by a faster encapsulation rate against a novel antigen, and higher levels of phenoloxidase in haemolymph. Thus, the present study indicates that pheromones could transmit information about males' parasite resistance ability and may work as a reliable sexual ornament for female choice. PMID:12204128

  1. Synthetic Co-Attractants of the Aggregation Pheromone of the Date Palm Root Borer Oryctes agamemnon.

    Science.gov (United States)

    Hasni, Narjes; Pinier, Centina; Imed, Cheraief; Ouhichi, Monêem; Couzi, Philippe; Chermiti, Brahim; Frérot, Brigitte; Saïd, Imen; Rochat, Didier

    2017-07-01

    Laboratory and field investigations to identify and evaluate plant co-attractants of the aggregation pheromone of the date palm pest Oryctes agamemnon are reported. Volatiles emitted by freshly cut palm core and palm core with feeding males, were collected, analyzed by gas chromatography coupled to mass spectrometry and evaluated in olfactometers alone or combined with synthetic pheromone. A collection of palm odor without male effluvia was attractive alone and enhanced attraction to synthetic pheromone in an olfactometer similar to that to a collection of palm odor emitted with feeding males and containing natural pheromone. Behavioral responses to collections of palm volatiles were correlated to the amount of volatiles material in them. Enhancement of the attractiveness of the pheromone was not correlated to chemicals specific to beetle feeding. The chemicals common to the active collections extracts were benzoate esters, mostly ethyl benzoate, anisole derivatives and sesquiterpenes. Blends of the most abundant components of the extracts were evaluated for enhancement of the attractiveness of pheromone (1 μg) in olfactometers at 1 or 10 μg doses. The mixtures were further evaluated by field trapping in Tunisia at 3-10 mg/day using reference (6 mg/day) or experimental pheromone formulations. A mixture of ethyl benzoate, 4-methylanisole and farnesol (1:1:1 w/w at 6.5 mg/day) enhanced captures in pheromone baited traps in 2014 and 2015 and this mixture was as active as the natural palm bait. The practical prospect of the result for the management for O. agamemnon, and other palm beetles is discussed.

  2. Effects of oil drops containing Lactobacillus salivarius WB21 on periodontal health and oral microbiota producing volatile sulfur compounds.

    Science.gov (United States)

    Suzuki, Nao; Tanabe, Kazunari; Takeshita, Toru; Yoneda, Masahiro; Iwamoto, Tomoyuki; Oshiro, Sueko; Yamashita, Yoshihisa; Hirofuji, Takao

    2012-03-01

    The objective of this paper is to evaluate the effects of oil drops containing Lactobacillus salivarius WB21 on periodontal health and oral microbiota producing volatile sulfur compounds (VSCs). For this study, 42 subjects were randomly assigned to receive oil samples containing L. salivarius WB21 or a placebo for two weeks. Oral assessment and saliva collection were performed on days 1 and 15. Bacterial analysis was performed using the real-time polymerase chain reaction and terminal restriction fragment length polymorphism (T-RFLP). In both the experimental and placebo groups, the average probing depth, number of periodontal pockets, and the percentage of bleeding on probing (BOP) decreased while stimulated salivary flow increased on day 15. BOP was reduced in the experimental group compared with the placebo group (P = 0.010). In the experimental group, total bacterial numbers decreased, and the number of L. salivarius increased. The number of Prevotella intermedia, which is correlated with hydrogen sulfide concentration in mouth air, increased in the placebo group and did not change in the experimental group. T-RFLP analysis found that the peak area proportions representing Porphyromonas gingivalis, P. intermedia, Tannerella forsythensis, and Fusobacterium nucleatum decreased in the experimental group, although there was no significant change in the bacterial composition. Thus we observed oil drops containing L. salivarius WB21 improved BOP and inhibited the reproduction of total and VSC-producing periodontopathic bacteria compared with the placebo group, but also showed the limit of its efficacy in controlling VSCs producing and periodontal pathogens.

  3. Acidogenic fermentation characteristics of different types of protein-rich substrates in food waste to produce volatile fatty acids.

    Science.gov (United States)

    Shen, Dongsheng; Yin, Jun; Yu, Xiaoqin; Wang, Meizhen; Long, Yuyang; Shentu, Jiali; Chen, Ting

    2017-03-01

    In this study, tofu and egg white, representing typical protein-rich substrates in food waste based on vegetable and animal protein, respectively, were investigated for producing volatile fatty acids (VFAs) by acidogenic fermentation. VFA production, composition, conversion pathways and microbial communities in acidogenesis from tofu and egg white with and without hydrothermal (HT) pretreatment were compared. The results showed HT pretreatment could improve the VFA production of tofu but not for egg white. The optimum VFA yields were 0.46g/gVS (tofu with HT) and 0.26g/gVS (egg white without HT), respectively. Tofu could directly produce VFAs through the Stickland reaction, while egg white was converted to lactate and VFAs simultaneously. About 30-40% of total protein remained in all groups after fermentation. Up to 50% of the unconverted soluble protein in the HT groups was protease. More lactate-producing bacteria, mainly Leuconostoc and Lactobacillus, were present during egg white fermentation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Asymmetric total synthesis of a putative sex pheromone component from the parasitoid wasp Trichogramma turkestanica

    NARCIS (Netherlands)

    Geerdink, Danny; Buter, Jeffrey; van Beek, Teris A.; Minnaard, Adriaan J.

    2014-01-01

    Virgin females of the parasitoid wasp Trichogramma turkestanica produce minute amounts of a sex pheromone, the identity of which has not been fully established. The enantioselective synthesis of a putative component of this pheromone, (6S,8S,10S)-4,6,8,10-tetramethyltrideca-2E,4E-dien-1-ol (2), is

  5. Enzymatic activities produced by mixed Saccharomyces and non-Saccharomyces cultures: relationship with wine volatile composition.

    Science.gov (United States)

    Maturano, Yolanda Paola; Assof, Mariela; Fabani, María Paula; Nally, María Cristina; Jofré, Viviana; Rodríguez Assaf, Leticia Anahí; Toro, María Eugenia; Castellanos de Figueroa, Lucía Inés; Vazquez, Fabio

    2015-11-01

    During certain wine fermentation processes, yeasts, and mainly non-Saccharomyces strains, produce and secrete enzymes such as β-glucosidases, proteases, pectinases, xylanases and amylases. The effects of enzyme activity on the aromatic quality of wines during grape juice fermentation, using different co-inoculation strategies of non-Saccharomyces and Saccharomyces cerevisiae yeasts, were assessed in the current study. Three strains with appropriate enological performance and high enzymatic activities, BSc562 (S. cerevisiae), BDv566 (Debaryomyces vanrijiae) and BCs403 (Candida sake), were assayed in pure and mixed Saccharomyces/non-Saccharomyces cultures. β-Glucosidase, pectinase, protease, xylanase and amylase activities were quantified during fermentations. The aromatic profile of pure and mixed cultures was determined at the end of each fermentation. In mixed cultures, non-Saccharomyces species were detected until day 4-5 of the fermentation process, and highest populations were observed in MSD2 (10% S. cerevisiae/90% D. vanrijiae) and MSC1 (1% S. cerevisiae/99% C. sake). According to correlation and multivariate analysis, MSD2 presented the highest concentrations of terpenes and higher alcohols which were associated with pectinase, amylase and xylanase activities. On the other hand, MSC1 high levels of β-glucosidase, proteolytic and xylanolytic activities were correlated to esters and fatty acids. Our study contributes to a better understanding of the effect of enzymatic activities by yeasts on compound transformations that occur during wine fermentation.

  6. Pheromone biosynthesis in bark beetles.

    Science.gov (United States)

    Tittiger, Claus; Blomquist, Gary J

    2017-12-01

    Pine bark beetles rely on aggregation pheromones to coordinate mass attacks and thus reproduce in host trees. The structural similarity between many pheromone components and those of defensive tree resin led to early suggestions that pheromone components are metabolic derivatives of ingested precursors. This model has given way to our current understanding that most pheromone components are synthesized de novo. Their synthesis involves enzymes that modify products from endogenous metabolic pathways; some of these enzymes have been identified and characterized. Pheromone production is regulated in a complex way involving multiple signals, including JH III. This brief review summarizes progress in our understanding of this highly specialized metabolic process. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. A Biologically Active Analog of the Sex Pheromone of the Emerald Ash Borer, Agrilus planipennis.

    Science.gov (United States)

    Silk, P J; Ryall, K; Mayo, P; MaGee, D I; Leclair, G; Fidgen, J; Lavallee, R; Price, J; McConaghy, J

    2015-03-01

    The emerald ash borer, Agrilus planipennis (Coleoptera: Buprestidae) (EAB), is an invasive species causing unprecedented levels of mortality to ash trees in its introduced range. The female-produced sex pheromone of EAB has been shown to contain the macrocyclic lactone (3Z)-dodecen-12-olide. This compound and its geometrical isomer, (3E)-dodecen-12-olide, have been demonstrated previously to be EAG active and, in combination with a host-derived green leaf volatile, (3Z)-hexenol, to be attractive to male EAB in green prism traps deployed in the ash tree canopy. In the current study, we show that the saturated analog, dodecan-12-olide, is similarly active, eliciting an antennal response and significant attraction of EAB in both olfactometer and trapping bioassays in green traps with (3Z)-hexenol. Conformational modeling of the three lactones reveals that their energies and shapes are very similar, suggesting they might share a common receptor in EAB antennae. These findings provide new insight into the pheromone ecology of this species, highlighting the apparent plasticity in response of adults to the pheromone and its analog. Both of the unsaturated isomers are costly to synthesize, involving multistep, low-yielding processes. The saturated analog can be made cheaply, in high yield, and on large scale via Mitsunobu esterification of a saturated ω-hydroxy acid or more simply by Baeyer-Villiger oxidation of commercially available cyclododecanone. The analog can thus provide an inexpensive option as a lure for detection surveys as well as for possible mitigation purposes, such as mating disruption.

  8. Characterization of Odorant Receptors from a Non-ditrysian Moth, Eriocrania semipurpurella Sheds Light on the Origin of Sex Pheromone Receptors in Lepidoptera.

    Science.gov (United States)

    Yuvaraj, Jothi Kumar; Corcoran, Jacob A; Andersson, Martin N; Newcomb, Richard D; Anderbrant, Olle; Löfstedt, Christer

    2017-11-01

    Pheromone receptors (PRs) are essential in moths to detect sex pheromones for mate finding. However, it remains unknown from which ancestral proteins these specialized receptors arose. The oldest lineages of moths, so-called non-ditrysian moths, use short-chain pheromone components, secondary alcohols, or ketones, so called Type 0 pheromones that are similar to many common plant volatiles. It is, therefore, possible that receptors for these ancestral pheromones evolved from receptors detecting plant volatiles. Hence, we identified the odorant receptors (ORs) from a non-ditrysian moth, Eriocrania semipurpurella (Eriocraniidae, Lepidoptera), and performed functional characterization of ORs using HEK293 cells. We report the first receptors that respond to Type 0 pheromone compounds; EsemOR3 displayed highest sensitivity toward (2S, 6Z)-6-nonen-2-ol, whereas EsemOR5 was most sensitive to the behavioral antagonist (Z)-6-nonen-2-one. These receptors also respond to plant volatiles of similar chemical structures, but with lower sensitivity. Phylogenetically, EsemOR3 and EsemOR5 group with a plant volatile-responding receptor from the tortricid moth Epiphyas postvittana (EposOR3), which together reside outside the previously defined lepidopteran PR clade that contains the PRs from more derived lepidopteran families. In addition, one receptor (EsemOR1) that falls at the base of the lepidopteran PR clade, responded specifically to β-caryophyllene and not to any other additional plant or pheromone compounds. Our results suggest that PRs for Type 0 pheromones have evolved from ORs that detect structurally-related plant volatiles. They are unrelated to PRs detecting pheromones in more derived Lepidoptera, which, in turn, also independently may have evolved a novel function from ORs detecting plant volatiles. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  9. Significance of volatile compounds produced by spoilage bacteria in vacuum-packed cold-smoked salmon ( Salmo salar ) analyzed by GC-MS and multivariate regression

    DEFF Research Database (Denmark)

    Jørgensen, Lasse Vigel; Huss, Hans Henrik; Dalgaard, Paw

    2001-01-01

    alcohols, which were produced by microbial activity. Partial least- squares regression of volatile compounds and sensory results allowed for a multiple compound quality index to be developed. This index was based on volatile bacterial metabolites, 1- propanol and 2-butanone, and 2-furan......, 1- penten-3-ol, and 1-propanol. The potency and importance of these compounds was confirmed by gas chromatography- olfactometry. The present study provides valuable information on the bacterial reactions responsible for spoilage off-flavors of cold-smoked salmon, which can be used to develop...

  10. Neurotoxicology of insecticides and pheromones

    National Research Council Canada - National Science Library

    Narahashi, Toshio

    1979-01-01

    The purpose of this symposium was to provide a forum where a variety of scientists who were interested in the interactions of insecticides and pheromones with the nervous system got together to exchange their views...

  11. Natural variation in dauer pheromone production and sensing supports intraspecific competition in nematodes.

    Science.gov (United States)

    Bose, Neelanjan; Meyer, Jan M; Yim, Joshua J; Mayer, Melanie G; Markov, Gabriel V; Ogawa, Akira; Schroeder, Frank C; Sommer, Ralf J

    2014-07-07

    Dauer formation, a major nematode survival strategy, represents a model for small-molecule regulation of metazoan development [1-10]. Free-living nematodes excrete dauer-inducing pheromones that have been assumed to target conspecifics of the same genotype [9, 11]. However, recent studies in Pristionchus pacificus revealed that the dauer pheromone of some strains affects conspecifics of other genotypes more strongly than individuals of the same genotype [12]. To elucidate the mechanistic basis for this intriguing cross-preference, we compared six P. pacificus wild isolates to determine the chemical composition of their dauer-inducing metabolomes and responses to individual pheromone components. We found that these isolates produce dauer pheromone blends of different composition and respond differently to individual pheromone components. Strikingly, there is no correlation between production of and dauer response to a specific compound in individual strains. Specifically, pheromone components that are abundantly produced by one genotype induce dauer formation in other genotypes, but not necessarily in the abundant producer. Furthermore, some genotypes respond to pheromone components they do not produce themselves. These results support a model of intraspecific competition in nematode dauer formation. Indeed, we observed intraspecific competition among sympatric strains in a novel experimental assay, suggesting a new role of small molecules in nematode ecology. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Comparison of consecutive harvests versus blending treatments to produce lower alcohol wines from Cabernet Sauvignon grapes: Impact on wine volatile composition and sensory properties.

    Science.gov (United States)

    Schelezki, Olaf J; Šuklje, Katja; Boss, Paul K; Jeffery, David W

    2018-09-01

    This study extends previous work on Cabernet Sauvignon wines of lowered alcohol concentrations produced by pre-fermentatively substituting proportions of juice from an overripe crop with "green harvest wine" or water to adjust initial sugar concentrations. Resulting wines were assessed for their volatile compositions and sensory characteristics to evaluate the suitability of this winemaking approach to managing wine alcohol concentrations in warm viticulture regions. Wines from water or green harvest wine substitution were also compared to wines of similar alcohol content produced from earlier harvested grapes. Implementation of water substitution in particular resulted in minor alterations of wine volatile composition compared to the control, and positive aroma and flavour characteristics were preserved. However, overripe sensory attributes such as 'hotness' and 'port wine' were conserved whereas they were absent in wines of similar alcohol level made from earlier harvested grapes, thereby emphasising the relevance of grape (over)maturity when producing lower alcohol wines. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Host plant odours enhance the responses of adult banana weevil to the synthetic aggregation pheromone Cosmolure+

    NARCIS (Netherlands)

    Tinzaara, W.; Gold, C.S.; Dicke, M.; Huis, van A.; Ragama, P.E.

    2007-01-01

    Attraction of adult banana weevil, Cosmopolites sordidus to volatiles from banana pseudostem tissue and the synthetic pheromone Cosmolure+ presented singly or in combination, was studied in the laboratory and in the field. Olfactometric studies in the laboratory showed that 50 g of fermented banana

  14. Courtship pheromones in parasitic wasps: comparison of bioactive and inactive hydrocarbon profiles by multivariate statistical methods

    NARCIS (Netherlands)

    Steiner, S.; Mumm, R.; Ruther, J.

    2007-01-01

    Cuticular hydrocarbons play a significant role in the regulation of cuticular permeability and also in the chemical communication of insects. In the parasitoid Lariophagus distinguendus (Hymenoptera: Pteromalidae), male courtship behavior is mediated by a female-produced sex pheromone. Previous

  15. Captura de Rhynchophorus palmarum L. (Coleoptera: curculionidae em armadilhas iscadas com o feromônio de agregação e compostos voláteis de frutos do abacaxi Trap catches of Rhynchophorus palmarum L. (Coleoptera: curculionidae baited with its aggregation pheromone and volatile compounds from pineapple

    Directory of Open Access Journals (Sweden)

    Adriana Guimarães Duarte

    2003-04-01

    Full Text Available O objetivo deste trabalho foi determinar os índices de captura de Rhynchophorus palmarum em armadilhas iscadas com o feromônio de agregação, 6-metil-2(E-hepten-4-ol (rincoforol, associado a toletes de cana-de-açúcar, a pedaços de frutos do abacaxi e a seis compostos voláteis isolados de frutos do abacaxi. Os compostos voláteis do abacaxi são caracterizados por uma mistura de ésteres metílicos e etílicos, sendo o octanoato de metila e o octanoato de etila os mais abundantes. As armadilhas iscadas com o rincoforol associado a toletes de cana-de-açúcar e as iscas com rincoforol associado a pedaços de abacaxi não apresentaram diferenças significativas no número de besouros capturados. No entanto, ambas apresentaram índices de captura superiores àquelas em que o rincoforol foi utilizado em associação com voláteis do abacaxi. Não se observaram efeitos significativos do local e época de captura, nem no número de machos e de fêmeas capturados.The aim of this work was to investigate the capture of Rhynchophorus palmarum in traps baited with its aggregation pheromone, 6-methyl-2(E-hepten-4-ol (rhynchophorol, in association with sugar cane, pieces of pineapple fruit, and six volatile compounds from pineapple. A mixture of methyl and ethyl esters, being methyl octanoate and ethyl octanoate the most abundant, characterizes the volatile compounds from pineapple fruits. Traps baited with rhynchophorol in association with sugar cane and those baited with rhynchophorol in association with pieces of pineapple, showed no significant differences in the number of trapped weevils. However, both traps caught significantly more weevils, than those baited with rhynchophorol in association with pineapple volatiles. There were no significant effects from place and time or in the number of male and female weevils trapped.

  16. Factors Influencing Male Plutella xylostella (Lepidoptera: Plutellidae) Capture Rates in Sex Pheromone-Baited Traps on Canola in Western Canada.

    Science.gov (United States)

    Miluch, C E; Dosdall, L M; Evenden, M L

    2014-12-01

    Optimization of male moth trapping rates in sex pheromone-baited traps plays a key role in managing Plutella xylostella (L.). We investigated various ways to increase the attractiveness of pheromone-baited traps to P. xylostella in canola agroecosystems in AB, Canada. Factors tested included pheromone blend and dose, addition of a green leaf volatile to the pheromone at different times during the season, lure type, trap color, and height. The industry standard dose of 100 μg of pheromone (four-component blend) per lure (ConTech Enterprises Inc., Delta, British Columbia [BC], Canada) captured the most moths in the two lure types tested. Traps baited with pheromone released from gray rubber septa captured more males than those baited with red rubber septa. Traps baited with lures in which Z11-16: Ac is the main component attracted significantly more moths than those in which Z11-16: Ald is the main component. The addition of the green leaf volatile, (Z)-3-hexenyl acetate, to pheromone at a range of doses, did not increase moth capture at any point during the canola growing season. Unpainted white traps captured significantly more male moths than pheromone-baited traps that were painted yellow. Trap height had no significant effect on moth capture. Recommendations for monitoring P. xylostella in canola agroecosystems of western Canada include using a pheromone blend with Z11-16: Ac as the main component released from gray rubber septa at a dose of 100 μg. © 2014 Entomological Society of America.

  17. Volatile profile characterisation of Chilean sparkling wines produced by traditional and Charmat methods via sequential stir bar sorptive extraction.

    Science.gov (United States)

    Ubeda, C; Callejón, R M; Troncoso, A M; Peña-Neira, A; Morales, M L

    2016-09-15

    The volatile compositions of Charmat and traditional Chilean sparkling wines were studied for the first time. For this purpose, EG-Silicone and PDMS polymeric phases were compared and, afterwards, the most adequate was selected. The best extraction method turned out to be a sequential extraction in the headspace and by immersion using two PDMS twisters. A total of 130 compounds were determined. In traditional Chilean sparkling wines, ethyl esters were significantly higher, while acetic esters and ketones were predominant in the Charmat wines. PCA and LDA confirmed the differences in the volatile profiles between the production methods (traditional vs. Charmat). Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Effects of natural and synthetic alarm pheromone and individual pheromone components on foraging behavior of the giant Asian honey bee, Apis dorsata.

    Science.gov (United States)

    Li, Jianjun; Wang, Zhengwei; Tan, Ken; Qu, Yufeng; Nieh, James C

    2014-10-01

    Social pollinators such as honey bees face attacks from predators not only at the nest, but also during foraging. Pollinating honey bees can therefore release alarm pheromones that deter conspecifics from visiting dangerous inflorescences. However, the effect of alarm pheromone and its chemical components upon bee avoidance of dangerous food sources remains unclear. We tested the responses of giant honey bee foragers, Apis dorsata, presented with alarm pheromone at a floral array. Foragers investigated the inflorescence with natural alarm pheromone, but 3.3-fold more foragers preferred to land on the 'safe' inflorescence without alarm pheromone. Using gas chromatography-mass spectrometry analysis, we identified eight chemical components in the alarm pheromone, of which three components (1-octanol, decanal and gamma-octanoic lactone) have not previously been reported in this species. We bioassayed six major compounds and found that a synthetic mixture of these compounds elicited behaviors statistically indistinguishable from responses to natural alarm pheromone. By testing each compound separately, we show that gamma-octanoic lactone, isopentyl acetate and (E)-2-decen-1-yl acetate are active compounds that elicit significant alarm responses. Gamma-octanoic lactone elicited the strongest response to a single compound and has not been previously reported in honey bee alarm pheromone. Isopentyl acetate is widely found in the alarm pheromones of sympatric Asian honey bee species, and thus alarmed A. dorsata foragers may produce information useful for conspecifics and heterospecifics, thereby broadening the effects of alarm information on plant pollination. © 2014. Published by The Company of Biologists Ltd.

  19. Perception of volatiles produced by UVC-irradiated plants alters the response to viral infection in naïve neighboring plants.

    Science.gov (United States)

    Yao, Youli; Danna, Cristian H; Ausubel, Frederick M; Kovalchuk, Igor

    2012-07-01

    Interplant communication of stress via volatile signals is a well-known phenomenon. It has been shown that plants undergoing stress caused by pathogenic bacteria or insects generate volatile signals that elicit defense response in neighboring naïve plants. Similarly, we have recently shown that naïve plants sharing the same gaseous environment with UVC-exposed plants exhibit similar changes in genome instability as UVC-exposed plants. We found that methyl salicylate (MeSA) and methyl jasmonate (MeJA) serve as volatile signals communicating genome instability (as measured by an increase in the homologous recombination frequency). UVC-exposed plants produce high levels of MeSA and MeJA, a response that is missing in an npr1 mutant. Concomitantly, npr1 mutants are impaired in communicating the signal leading to genome instability, presumably because this mutant does not develop new necrotic lesion after UVC irradiation as observed in wt plants. To analyze the potential biological significance of such plant-plant communication, we have now determined whether bystander plants that receive volatile signals from UVC-irradiated plants, become more resistant to UVC irradiation or infection with oilseed rape mosaic virus (ORMV). Specifically, we analyzed the number of UVC-elicited necrotic lesions, the level of anthocyanin pigments, and the mRNA levels corresponding to ORMV coat protein and the NPR1-regulated pathogenesis-related protein PR1 in the irradiated or virus-infected bystander plants that have been previously exposed to volatiles produced by UVC-irradiated plants. These experiments showed that the bystander plants responded similarly to control plants following UVC irradiation. Interestingly, however, the bystander plants appeared to be more susceptible to ORMV infection, even though PR1 mRNA levels in systemic tissue were significantly higher than in the control plants, which indicates that bystander plants could be primed to strongly respond to bacterial

  20. Communication disruption of guava moth (Coscinoptycha improbana) using a pheromone analog based on chain length.

    Science.gov (United States)

    Suckling, D M; Dymock, J J; Park, K C; Wakelin, R H; Jamieson, L E

    2013-09-01

    The guava moth, Coscinoptycha improbana, an Australian species that infests fruit crops in commercial and home orchards, was first detected in New Zealand in 1997. A four-component pheromone blend was identified but is not yet commercially available. Using single sensillum recordings from male antennae, we established that the same olfactory receptor neurons responded to two guava moth sex pheromone components, (Z)-11-octadecen-8-one and (Z)-12-nonadecen-9-one, and to a chain length analog, (Z)-13-eicosen-10-one, the sex pheromone of the related peach fruit moth, Carposina sasakii. We then field tested whether this non-specificity of the olfactory neurons might enable disruption of sexual communication by the commercially available analog, using male catch to synthetic lures in traps in single-tree, nine-tree and 2-ha plots. A disruptive pheromone analog, based on chain length, is reported for the first time. Trap catches for guava moth were disrupted by three polyethylene tubing dispensers releasing the analog in single-tree plots (86% disruption of control catches) and in a plots of nine trees (99% disruption). Where peach fruit moth pheromone dispensers were deployed at a density of 1000/ha in two 2-ha areas, pheromone traps for guava moth were completely disrupted for an extended period (up to 470 days in peri-urban gardens in Mangonui and 422 days in macadamia nut orchards in Kerikeri). In contrast, traps in untreated areas over 100 m away caught 302.8 ± 128.1 moths/trap in Mangonui and 327.5 ± 78.5 moths/ trap in Kerikeri. The longer chain length in the pheromone analog has greater longevity than the natural pheromone due to its lower volatility. Chain length analogs may warrant further investigation for mating disruption in Lepidoptera, and screening using single-sensillum recording is recommended.

  1. Sex Pheromone of the Almond Moth and the Indian Meal Moth: cis-9, trans-12-Tetradecadienyl Acetate.

    Science.gov (United States)

    Kuwahara, Y; Kitamura, C; Takashi, S; Hara, H; Ishii, S; Fukami, H

    1971-02-26

    Female moths of different species but belonging to the same subfamily produce an identical compound as their sex pheromone. The sex pheromone of the almond moth, Cadra cautella (Walker), and the Indian meal moth, Plodia interpunctella (Hübner), has been isolated and identified as cis-9, trans-12-tetradecadienyl acetate.

  2. Selective breeding for increased pheromone production in the boll weevil (Coleoptera: Curculionidae)

    International Nuclear Information System (INIS)

    McCoy, J.R.; Wright, J.E.

    1990-01-01

    The male boll weevil, Anthonomus grandis grandis Boheman, uses an aggregating pheromone to attract females, after which mating often occurs. Sterile boll weevil release programs depend upon this phenomenon to produce sterile matings with feral females. In an effort to increase the effectiveness of the individual sterile male and thereby reduce the number of sterile males required per hectare, a selective-breeding system was used to increase the total pheromone produced by individual male boll weevils. This breeding program increased the total pheromone production by individual male boll weevils to 4.5 times that of the parent population. After irradiation-induced sterilization, there remained 2.2 times more pheromone produced by the selected strain. Therefore, these sterile weevils should be about 2.2 times more attractive to feral females than the parent weevils now in use, and they have the potential to reduce the number of sterile males required in a sterile release program

  3. Ejaculate of sneaker males is pheromonally inconspicuous in the black goby, Gobius niger (Teleostei, Gobiidae).

    Science.gov (United States)

    Locatello, L; Mazzoldi, C; Rasotto, M B

    2002-11-01

    The black goby, Gobius niger, shows alternative male mating tactics, i.e., parental and sneaker males. Males release a sexual pheromone that attracts females and stimulates aggressive displays in males. This pheromone is produced by the mesorchial gland, a structure well developed in parental males but markedly undeveloped in sneakers. We measured the behavioral response of parental males to the ejaculates of males performing different reproductive tactics. Parental males reacted to the ejaculate of other parental males, with stereotypic aggressive behaviors, but not to the ejaculate of sneakers; consequently sneaker male ejaculate appears to be pheromonally inconspicuous. Copyright 2002 Wiley-Liss, Inc.

  4. Genes involved in sex pheromone biosynthesis of Ephestia cautella, an important food storage pest, are determined by transcriptome sequencing

    KAUST Repository

    Antony, Binu

    2015-07-18

    Background Insects use pheromones, chemical signals that underlie all animal behaviors, for communication and for attracting mates. Synthetic pheromones are widely used in pest control strategies because they are environmentally safe. The production of insect pheromones in transgenic plants, which could be more economical and effective in producing isomerically pure compounds, has recently been successfully demonstrated. This research requires information regarding the pheromone biosynthetic pathways and the characterization of pheromone biosynthetic enzymes (PBEs). We used Illumina sequencing to characterize the pheromone gland (PG) transcriptome of the Pyralid moth, Ephestia cautella, a destructive storage pest, to reveal putative candidate genes involved in pheromone biosynthesis, release, transport and degradation. Results We isolated the E. cautella pheromone compound as (Z,E)-9,12-tetradecadienyl acetate, and the major pheromone precursors 16:acyl, 14:acyl, E14-16:acyl, E12-14:acyl and Z9,E12-14:acyl. Based on the abundance of precursors, two possible pheromone biosynthetic pathways are proposed. Both pathways initiate from C16:acyl-CoA, with one involving ∆14 and ∆9 desaturation to generate Z9,E12-14:acyl, and the other involving the chain shortening of C16:acyl-CoA to C14:acyl-CoA, followed by ∆12 and ∆9 desaturation to generate Z9,E12-14:acyl-CoA. Then, a final reduction and acetylation generates Z9,E12-14:OAc. Illumina sequencing yielded 83,792 transcripts, and we obtained a PG transcriptome of ~49.5 Mb. A total of 191 PBE transcripts, which included pheromone biosynthesis activating neuropeptides, fatty acid transport proteins, acetyl-CoA carboxylases, fatty acid synthases, desaturases, β-oxidation enzymes, fatty acyl-CoA reductases (FARs) and fatty acetyltransferases (FATs), were selected from the dataset. A comparison of the E. cautella transcriptome data with three other Lepidoptera PG datasets revealed that 45 % of the sequences were shared

  5. A Forward Genetic Screen for Molecules Involved in Pheromone-Induced Dauer Formation in Caenorhabditis elegans

    Directory of Open Access Journals (Sweden)

    Scott J. Neal

    2016-05-01

    Full Text Available Animals must constantly assess their surroundings and integrate sensory cues to make appropriate behavioral and developmental decisions. Pheromones produced by conspecific individuals provide critical information regarding environmental conditions. Ascaroside pheromone concentration and composition are instructive in the decision of Caenorhabditis elegans to either develop into a reproductive adult or enter into the stress-resistant alternate dauer developmental stage. Pheromones are sensed by a small set of sensory neurons, and integrated with additional environmental cues, to regulate neuroendocrine signaling and dauer formation. To identify molecules required for pheromone-induced dauer formation, we performed an unbiased forward genetic screen and identified phd (pheromone response-defective dauer mutants. Here, we describe new roles in dauer formation for previously identified neuronal molecules such as the WD40 domain protein QUI-1 and MACO-1 Macoilin, report new roles for nociceptive neurons in modulating pheromone-induced dauer formation, and identify tau tubulin kinases as new genes involved in dauer formation. Thus, phd mutants define loci required for the detection, transmission, or integration of pheromone signals in the regulation of dauer formation.

  6. Do aphid colonies amplify their emission of alarm pheromone?

    Science.gov (United States)

    Hatano, Eduardo; Kunert, Grit; Bartram, Stefan; Boland, Wilhelm; Gershenzon, Jonathan; Weisser, Wolfgang W

    2008-09-01

    When aphids are attacked by natural enemies, they emit alarm pheromone to alert conspecifics. For most aphids tested, (E)-beta-farnesene (EBF) is the main, or only, constituent of the alarm pheromone. In response to alarm pheromone, alerted aphids drop off the plant, walk away, or attempt to elude predators. However, under natural conditions, EBF concentration might be low due to the low amounts emitted, to rapid air movement, or to oxidative degradation. To ensure that conspecifics are warned, aphids might conceivably amplify the alarm signal by emitting EBF in response to EBF emitted by other aphids. To examine whether such amplification occurs, we synthesized deuterated EBF (DEBF), which allowed us to differentiate between applied and aphid-derived chemical. Colonies of Acyrthosiphon pisum were treated with DEBF, and headspace volatiles were collected and analyzed for evidence of aphid-derived EBF. No aphid-derived EBF was detected, suggesting that amplification of the alarm signal does not occur. We discuss the disadvantages of alarm signal reinforcement.

  7. Effect of oral nitroethane and 2-nitropropanol administration on methane-producing activity and volatile fatty acid production in the ovine rumen

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, R.C.; Callaway, T.R.; Schultz, C.L.; Edrington, T.S.; Harvey, R.B.; Nisbet, D.J. [United States Department of Agriculture, Agricultural Research Service, Food and Feed Safety Research Unit, College Station, TX (United States); Carstens, G.E.; Miller, R.K. [Texas A and M University, College Station, TX (United States). Department of Animal Science

    2006-12-15

    Strategies are sought to reduce economic and environmental costs associated with ruminant methane emissions. The effect of oral nitroethane or 2-nitropropanol administration on ruminal methane-producing activity and volatile fatty acid production was evaluated in mature ewes. Daily administration of 24 and 72 mg nitroethane/kg body weight reduced (P < 0.05) methane-producing activity by as much as 45% and 69% respectively, when compared to control animals given no nitroethane. A daily odes of 120 mg 2-nitropropanol/kg body weight was needed to reduce (P < 0.05) methane-producing activity by 37% from that of untreated control animals. Reductions in methane-producing activity may have been diminished by the last day (day 5) of treatment, presumably due to ruminal adaptation. Oral administration of nitroethane or 2-nitropropanol had little or no effect on accumulations or molar proportions of volatile fatty acids in ruminal contents collected from the sheep. These results demonstrate that nitroethane was superior to 2-nitropropanol as a methane inhibitor and that both nitrocompounds reduced ruminal methanogenesis in vivo without redirecting the flow of reductant generated during fermentation to propionate and butyrate. (author)

  8. Of pheromones and kairomones: what receptors mediate innate emotional responses?

    Science.gov (United States)

    Fortes-Marco, Lluis; Lanuza, Enrique; Martinez-Garcia, Fernando

    2013-09-01

    Some chemicals elicit innate emotionally laden behavioral responses. Pheromones mediate sexual attraction, parental care or agonistic confrontation, whereas predators' kairomones elicit defensive behaviors in their preys. This essay explores the hypothesis that the detection of these semiochemicals relies on highly specific olfactory and/or vomeronasal receptors. The V1R, V2R, and formyl-peptide vomeronasal receptors bind their ligands in highly specific and sensitive way, thus being good candidates for pheromone- or kairomone-detectors (e.g., secreted and excreted proteins, peptides and lipophilic volatiles). The olfactory epithelium also expresses specific receptors, for example trace amine-associated receptors (TAAR) and guanylyl cyclase receptors (GC-D and other types), some of which bind kairomones and putative pheromones. However, most of the olfactory neurons express canonical olfactory receptors (ORs) that bind many ligands with different affinity, being not suitable for mediating responses to pheromones and kairomones. In this respect, trimethylthiazoline (TMT) is considered a fox-derived kairomone for mice and rats, but it seems to be detected by canonical ORs. Therefore, we have reassessed the kairomonal nature of TMT by analyzing the behavioral responses of outbred (CD1) and inbred mice (C57BL/J6) to TMT. Our results confirm that both mouse strains avoid TMT, which increases immobility in C57BL/J6, but not CD1 mice. However, mice of both strains sniff at TMT throughout the test and show no trace of TMT-induced contextual conditioning (immobility or avoidance). This suggests that TMT is not a kairomone but, similar to a loud noise, in high concentrations it induces aversion and stress as unspecific responses to a strong olfactory stimulation. Copyright © 2013 Wiley Periodicals, Inc.

  9. Queen pheromones: The chemical crown governing insect social life.

    Science.gov (United States)

    Holman, Luke

    2010-11-01

    Group-living species produce signals that alter the behavior and even the physiology of their social partners. Social insects possess especially sophisticated chemical communication systems that govern every aspect of colony life, including the defining feature of eusociality: reproductive division of labor. Current evidence hints at the central importance of queen pheromones, but progress has been hindered by the fact that such pheromones have only been isolated in honeybees. In a pair of papers on the ant Lasius niger, we identified and investigated a queen pheromone regulating worker sterility. The cuticular hydrocarbon 3-methylhentriacontane (3-MeC(31)) is correlated with queen maturity and fecundity and workers are also more likely to execute surplus queens that have low amounts of this chemical. Experiments with synthetic 3-MeC(31) found that it inhibits ovarian development in queenless workers and lowers worker aggression towards objects coated with it. Production of 3-MeC(31) by queens was depressed by an experimental immune challenge, and the same chemical was abundant on queenlaid eggs, suggesting that the workers' responses to the queen are conditional on her health and fecundity. Together with other studies, these results indicate that queen pheromones are honest signals of quality that simultaneously regulate multiple social behaviors.

  10. The evolution of female sex pheromones

    Directory of Open Access Journals (Sweden)

    Ally R. HARARI, Hadass STEINITZ

    2013-08-01

    Full Text Available The role of female sex pheromones in natural selection, particularly as a means for species recognition to avoid the generation of hybrid offspring with low fitness, has been widely explored and is generally accepted by scholars. However, the significance of sex pheromones in shaping mate choice (sexual selection and in competition over breeding resources (social selection has been largely ignored. The effect of sexual selection on sex pheromones as a sexually dimorphic signaling trait has been discounted because the amount of pheromone released by females is typically minute, while the role of sex pheromones in competition over breeding resources (other than mates has not yet been considered. As a result of natural selection, variation in sex pheromones among females is expected to be low, and males are not expected to choose their mates among pheromone-releasing conspecific females. Sexual selection, on the other hand, should drive the increase in pheromone variance among females, and males are expected to choose females based on this variation. Moreover, social selection resulting from more general social interactions, for example competition among females for breeding sites and food, should also promote variance among female sex pheromones. Here, we review the current evidence for each of the three selection processes acting on sex pheromones of female moths as an advertising trait. We suggest that the three selection types are not mutually exclusive but rather act together to promote different fitness components in diverse ecological situations [Current Zoology 59 (4: 569–578, 2013].

  11. Red wine produced from the Isabella and Ives cultivar (Vitis Labrusca: profile of volatiles and aroma descriptors

    Directory of Open Access Journals (Sweden)

    Narciza Maria de Oliveira ARCANJO

    2018-03-01

    Full Text Available Abstract Considering the potential consumption and economic the importance that Isabella and Ives wines represent in the Brazilian consumer market as well as the scarcity of scientific data examining their quality, the objective of this study was to investigate the sensory quality and the volatiles profile of these wines. The volatile compounds were extracted by headspace solid-phase microextraction (HS-SPME and a total of 54 compounds were detected in red wine samples including esters (23, terpenes (12, alcohols (10, aldehydes and ketones (5 and amines (1 as well as 3 compounds belonging to other classes. Isabella and Ives red wines were sensorially characterized by 14 descriptors, through quantitative descriptive analysis (QDA. The PCAs fruity descriptors were the primary contributors to the aroma profile of the analyzed wines due to the presence of ethyl acetate and esters, especially in the wine coded as QM, which exhibited the highest variety of compounds. The differences observed in the principal components analysis, might have been influenced by the grape composition of each wine. Although the wines were from the same region, each came from a different winery and was subject to unique production processes.

  12. Differential interactions of sex pheromone and plant odour in the olfactory pathway of a male moth.

    Directory of Open Access Journals (Sweden)

    Nina Deisig

    Full Text Available Most animals rely on olfaction to find sexual partners, food or a habitat. The olfactory system faces the challenge of extracting meaningful information from a noisy odorous environment. In most moth species, males respond to sex pheromone emitted by females in an environment with abundant plant volatiles. Plant odours could either facilitate the localization of females (females calling on host plants, mask the female pheromone or they could be neutral without any effect on the pheromone. Here we studied how mixtures of a behaviourally-attractive floral odour, heptanal, and the sex pheromone are encoded at different levels of the olfactory pathway in males of the noctuid moth Agrotis ipsilon. In addition, we asked how interactions between the two odorants change as a function of the males' mating status. We investigated mixture detection in both the pheromone-specific and in the general odorant pathway. We used a recordings from individual sensilla to study responses of olfactory receptor neurons, b in vivo calcium imaging with a bath-applied dye to characterize the global input response in the primary olfactory centre, the antennal lobe and c intracellular recordings of antennal lobe output neurons, projection neurons, in virgin and newly-mated males. Our results show that heptanal reduces pheromone sensitivity at the peripheral and central olfactory level independently of the mating status. Contrarily, heptanal-responding olfactory receptor neurons are not influenced by pheromone in a mixture, although some post-mating modulation occurs at the input of the sexually isomorphic ordinary glomeruli, where general odours are processed within the antennal lobe. The results are discussed in the context of mate localization.

  13. Volatile Compounds in Honey Produced in the Central Valley of Ñuble Province, Chile Compuestos Volatiles en Miel Producida en el Valle Central de la Provincia de Ñuble, Chile

    Directory of Open Access Journals (Sweden)

    María Pía Gianelli Barra

    2010-03-01

    Full Text Available Headspace solid-phase microextraction (SPME with an 85 µm Carboxen polydimethylsiloxane (CAR/PDMS fiber was used to extract volatile compounds, and a gas chromatograph equipped with a mass spectometry detector (GC-MS was used to identify the volatile compounds in honeys. Thirty-four different volatile compounds from the headspace of honey produced in the central valley of Ñuble Province, Chile, were extracted with fiber coating CAR/PDMS. The identified compounds were: 10 alcohols, 9 acids, 6 ketones, 3 aldehydes, 2 furans, 2 terpenes and 2 lactones. Only four of the volatile compounds had never been reported before as honey compounds; these being: 1,3-propanodiol, 2-methyl butanoic acid, 3,4-dimethyl-3-hexen-2-one, and 6-methyl-5-octen-2-one. These four compounds were found in three of the 10 analyzed samples. The compounds found in the highest percentage of area were ethanol, acetic acid, 1-hydroxy-2-propane, 3-hydroxy-2-butane, and furfural. However, the analyzed samples did not present a distinctive profile.La extracción de compuestos volátiles desde el espacio de cabeza de mieles se realiza mediante microextracción en fase sólida (SPME, utilizando una fibra de 85 µm de Carboxen polidimetilsiloxano (CAR/PDMS, el análisis de los compuestos volátiles se realiza mediante cromatografía de gases con detector de masa (GC-MS. Un total de 34 diferentes compuestos volátiles fueron extraídos desde el espacio de cabeza de mieles provenientes del valle central de la provincia de Ñuble con la fibra de CAR/PDMS. Los compuestos identificados fueron 10 alcoholes, 9 ácidos, 6 cetonas, 3 aldehídos, 2 furanos, 2 terpenos y 2 lactonas. De los compuestos volátiles sólo tres no han sido reportados con anterioridad en mieles, estos compuestos fueron: 1,3-propanodiol, ácido 2-metil butanoico, 3,4-dimetil-3-hexen-2-ona, 6-metil-5-octen-2-ona. Estos cuatro compuestos se encontraron en sólo tres de las 10 muestras analizadas. Los compuestos que se

  14. Variation in courtship ultrasounds of three Ostrinia moths with different sex pheromones

    DEFF Research Database (Denmark)

    Takanashi, Takuma; Nakano, Ryo; Surlykke, Annemarie

    2010-01-01

    energy at 40 kHz, but distinctly different from the ultrasound produced by O. furnacalis, consisting of groups of pulses peaking at 50 kHz and with substantially more energy up to 80 kHz. Despite overall similarities, temporal features and patterns of amplitude modulation differed significantly among...... the geographic populations of O. nubilalis and O. scapulalis, which differed in pheromone type. In contrast, no significant difference in hearing was found among the three species with regard to the most sensitive frequencies and hearing threshold levels. The patterns of variations in the songs and pheromones...... well reflected those of the phylogenetic relationships, implying that ultrasound and pheromone communications have diverged concordantly. Our results suggest that concordant evolution in sexual signals such as courtship ultrasounds and sex pheromones occurs in moths....

  15. Sex and aggregation pheromone transport after methyl eugenol consumption in male Bactrocera papayae

    International Nuclear Information System (INIS)

    Hee, Alvin K.W.; Tan, K.H.

    2000-01-01

    Amongst at least 52 sibling species complexes in the Oriental fruit fly, Bactrocera dorsalis Hendel (Diptera: Tephritidae), B. papayae (formerly Mal B) Drew and Hancock (Drew and Hancock 1994) is beginning to emerge as an economically important insect pest which poses a severe threat to the fruit cultivation in both subtropical and tropical countries. In Malaysia, B. papayae is one of the most damaging pests which infests many commercially grown fruits (Tan and Lee 1982). Like the Oriental fruit fly and its sibling species complex, B. carambolae Drew and Hancock, B. papayae is also strongly attracted to, and compulsively feeds on, methyl eugenol (ME) (Tan 1993). Chemical analyses revealed that in B. papayae males, ME is converted to phenylpropanoids which are then selectively accumulated in the rectal gland. Of the three major volatile substances, 2-allyl-4,5-dimethoyphenol (allyl-DMP) was detected in higher quantities relative to the trans-coniferyl alcohol (4-(3-hydroxy-E-propenyl)-2-methoxyphenol) (CF) and cis-3,4-dimethoxycinnamyl alcohol (cis-DMC) (Nishida et al. 1988a, 1988b). Behavioural studies have also shown that allyl-DMP and CF function as male sex and aggregation pheromone in B. papayae (Tan and Nishida 1996, Hee and Tan 1998). Allyl-DMP was found to be the most attractive compound and cis-DMC the least attractive to the males (Tan 1996). Consumption of ME enhances the mating competitiveness of males. This is demonstrated by the strong attraction of females to conspecific ME-fed males in wind tunnel experiments (Hee and Tan 1998). In male-male mating competition for virgin females, males that fed on ME performed significantly better (Shelly and Dewire 1994, Tan and Nishida 1996). Thus it appears that ME-fed males produced signals that were more attractive. However, the characterisation and understanding of the functions of these phenylpropanoids have not been accompanied by studies of their physiological mode of transport in male flies. The current

  16. Chemical investigations of volatile kairomones produced by Hyphantria cunea (Drury), a host of the parasitoid Chouioia cunea Yang.

    Science.gov (United States)

    Zhu, G; Pan, L; Zhao, Y; Zhang, X; Wang, F; Yu, Y; Fan, W; Liu, Q; Zhang, S; Li, M

    2017-04-01

    In tritrophic 'plants-herbivores-natural enemies' systems, there are relatively few reports concerning the role(s) of kairomones in pupal parasitism. Chouioia cunea Yang (Hymenoptera: Eulophidae), an endoparasitic chalcid wasp, parasitizes pupae of the fall webworm (Hyphantria cunea Drury). The role of host-related kairomones was investigated using electroantennogram (EAG) and behavioral techniques. Chemicals from some host stages (pupae) and host by-products (frass), induced arrestment behavior of female parasitoids, while chemicals from prepupae, were inactive. Gas chromatography-mass spectrometry analysis of volatiles collected from pupae, frass and prepupae using solid-phase microextration revealed seven compounds with carbon chain lengths ranging from C4 to C20. All of the chemicals elicited significant EAG responses in C. cunea. Y-tube olfactometer bioassays demonstrated a significant positive response of mated female C. cunea to 1-dodecene. These data provide a better understanding of the host location mechanisms of pupal parasitoid.

  17. A pheromone analogue affects the evaporation rate of (+)-disparlure in Lymantria dispar.

    Science.gov (United States)

    Sollai, Giorgia; Murgia, Sergio; Secci, Francesco; Frongia, Angelo; Cerboneschi, Anna; Masala, Carla; Liscia, Anna; Crnjar, Roberto; Solari, Paolo

    2014-04-01

    The gypsy moth Lymantria dispar L. is a widespread pest that causes economic damage to cork oak forests. Females produce the sex pheromone (+)-(7R,8S)-epoxy-2-methyloctadecane, known as (+)-disparlure [(+)D], for long-distance attraction of conspecific males. A (+)D analogue, 2-decyl-1-oxaspiro[2.2]pentane (OXP-01), neither stimulating nor attractive by itself, causes short-time inhibition of male response in a 1:1 blend with (+)D. The authors investigated whether and how the biological activity of the natural pheromone is affected by OXP-01 on a long-time basis (up to 16 days), also by looking at possible physicochemical reciprocal interactions. Blending of (+)D with OXP-01 decreased, under low evaporation rate, the pheromone effectiveness, as assessed by electroantennogram recordings. In male trappings, within the first 24 h, OXP-01 decreased and later enhanced the blend attractiveness, but only under high evaporation rate. Gas chromatography-mass spectroscopy indicates that quantitative retrieval of (+)D from blend cartridges is higher than for pure pheromone, and nuclear magnetic resonance measurements show that OXP-01 produces, possibly by Van der Waals interactions, a bimolecular entity with pheromone causing retention and lengthening of its attractiveness over time. The biological and physicochemical interactions between (+)D and OXP-01 may provide valuable information for the optimisation of pheromone-based control strategies for gypsy moths. © 2013 Society of Chemical Industry.

  18. Synthetic sex pheromone attracts the leishmaniasis vector Lutzomyia longipalpis (Diptera: Psychodidae) to traps in the field.

    Science.gov (United States)

    Bray, D P; Bandi, K K; Brazil, R P; Oliveira, A G; Hamilton, J G C

    2009-05-01

    Improving vector control remains a key goal in reducing the world's burden of infectious diseases. More cost-effective approaches to vector control are urgently needed, particularly because vaccines are unavailable and treatment is prohibitively expensive. The causative agent of American visceral leishmaniasis (AVL), Leishmania chagasi, Cunha and Chagas (Kinetoplastida: Trypanosomatidae), is transmitted between animal and human hosts by blood-feeding female sand flies attracted to mating aggregations formed on or above host animals by male-produced sex pheromones. Our results show the potential of using synthetic pheromones to control populations of Lutzomyia longipalpis Lutz and Neiva (Diptera: Psychodidae), the sand fly vector of one of the world's most important neglected diseases, AVL. We showed that a synthetic pheromone, (+/-)-9-methylgermacrene-B, produced from a low-cost plant intermediate, attracted females in the laboratory. By formulating dispensers that released this pheromone at a rate similar to that released by aggregating males, we were able to attract flies of both sexes to traps in the field. These dispensers worked equally well when deployed with mechanical light traps and inexpensive sticky traps. If deployed effectively, pheromone-based traps could be used to decrease AVL transmission rates through specific targeting and reduction of L. longipalpis populations. This is the first study to show attraction of a human disease-transmitting insect to a synthetic pheromone in the field, showing the general applicability of this novel approach for developing new tools for use in vector control.

  19. Synthetic Sex Pheromone Attracts the Leishmaniasis Vector Lutzomyia longipalpis (Diptera: Psychodidae) to Traps in the Field

    Science.gov (United States)

    Bray, D. P.; Bandi, K. K.; Brazil, R. P.; Oliveira, A. G.; Hamilton, J.G.C.

    2011-01-01

    Improving vector control remains a key goal in reducing the world’s burden of infectious diseases. More cost-effective approaches to vector control are urgently needed, particularly as vaccines are unavailable and treatment is prohibitively expensive. The causative agent of AVL, Leishmania chagasi, Cunha and Chagas (Kinetoplastida: Trypanosomatidae) is transmitted between animal and human hosts by blood-feeding female sand flies, attracted to mating aggregations formed on or above host animals by male-produced sex pheromones. Our results demonstrate the potential of using synthetic pheromones to control populations of Lutzomyia longipalpis Lutz and Neiva (Diptera: Psychodidae), the sand fly vector of one of the world’s most important neglected diseases, American visceral leishmaniasis (AVL). We showed that a synthetic pheromone, (±)-9-methylgermacrene-B, produced from a low-cost plant intermediate, attracted females in the laboratory. Then by formulating dispensers that released this pheromone at a rate similar to that released by aggregating males, we were able to attract flies of both sexes to traps in the field. These dispensers worked equally well when deployed with mechanical light traps and inexpensive sticky traps. If deployed effectively, pheromone-based traps could be used to decrease AVL transmission rates through specific targeting and reduction of L. longipalpis populations. This is the first study to show attraction of a human disease-transmitting insect to a synthetic pheromone in the field, demonstrating the general applicability of this novel approach for developing new tools for use in vector control. PMID:19496409

  20. Identification and Isolation of Human Alarm Pheromones

    National Research Council Canada - National Science Library

    Mujica-Parodi, Lilianne R; Strey, Helmut

    2006-01-01

    .... Task I, Optimization of Sample Collection, focused on the collection of the putative alarm pheromone via axillary sweat samples obtained during reference (physical exercise) and arousal (skydive) conditions...

  1. Synthesis and metabolism of pheromones and pheromone analogues

    International Nuclear Information System (INIS)

    Ding, Y.S.

    1987-01-01

    [9, 10- 3 H 2 ]Z9-14:Ac was synthesized at high specific activity ( 3 H, 58 Ci/mmole) by partial tritiation of the corresponding alkyne and was converted to the labeled Z9-14:OH and Z9-14:Al to study tissue specificity of acetate esterase (E), alcohol oxidase (OX), and aldehyde dehydrogenase (ALDH) in male and female Heliothis virescens. Soluble and membrane-associated enzyme activities were determined by radio-TLC assays. Compounds of the tritium-labeled Z11-16 series were synthesized and their in vitro fates examined as well. In order to achieve an alternative approach in which (1) pheromone receptor proteins would be stoichiometrically and irreversibly modified, or (2) pheromone-catabolizing enzymes are inactivated by tight-binding or irreversible inhibitors, we have designed analogues of pheromones of lepidopterous insect pests and assayed their biological activity in vitro and in vivo. Various fluorinated molecules such as acyl fluorides, fluoroolefins, 2-fluoro aldehydes, 2,2-difluoro aldehydes and trifluoromethyl ketones were synthesized. The synthesis of some other functional groups such as cyclopropanones, cyclopropanols, cyclopropyl carbinols, cyclopropyl aldehydes and Michael acceptors will also be discussed

  2. The investment in scent: time-resolved metabolic processes in developing volatile-producing Nigella sativa L. seeds.

    Directory of Open Access Journals (Sweden)

    Wentao Xue

    Full Text Available The interplay of processes in central and specialized metabolisms during seed development of Nigella sativa L. was studied by using a high-throughput metabolomics technology and network-based analysis. Two major metabolic shifts were identified during seed development: the first was characterized by the accumulation of storage lipids (estimated as total fatty acids and N-compounds, and the second by the biosynthesis of volatile organic compounds (VOCs and a 30% average decrease in total fatty acids. Network-based analysis identified coordinated metabolic processes during development and demonstrated the presence of five network communities. Enrichment analysis indicated that different compound classes, such as sugars, amino acids, and fatty acids, are largely separated and over-represented in certain communities. One community displayed several terpenoids and the central metabolites, shikimate derived amino acids, raffinose, xylitol and glycerol-3-phosphate. The latter are related to precursors of the mevalonate-independent pathway for VOC production in the plastid; also plastidial fatty acid 18∶3n-3 abundant in "green" seeds grouped with several major terpenes. The findings highlight the interplay between the components of central metabolism and the VOCs. The developmental regulation of Nigella seed metabolism during seed maturation suggests a substantial re-allocation of carbon from the breakdown of fatty acids and from N-compounds, probably towards the biosynthesis of VOCs.

  3. Old maids have more appeal: effects of age and pheromone source on mate attraction in an orb-web spider.

    Science.gov (United States)

    Cory, Anna-Lena; Schneider, Jutta M

    2016-01-01

    Background. In many insects and spider species, females attract males with volatile sex pheromones, but we know surprisingly little about the costs and benefits of female pheromone emission. Here, we test the hypothesis that mate attraction by females is dynamic and strategic in the sense that investment in mate attraction is matched to the needs of the female. We use the orb-web spider Argiope bruennichi in which females risk the production of unfertilised egg clutches if they do not receive a copulation within a certain time-frame. Methods. We designed field experiments to compare mate attraction by recently matured (young) females with females close to oviposition (old). In addition, we experimentally separated the potential sources of pheromone transmission, namely the female body and the web silk. Results. In accordance with the hypothesis of strategic pheromone production, the probability of mate attraction and the number of males attracted differed between age classes. While the bodies and webs of young females were hardly found by males, the majority of old females attracted up to two males within two hours. Old females not only increased pheromone emission from their bodies but also from their webs. Capture webs alone spun by old females were significantly more efficient in attracting males than webs of younger females. Discussion. Our results suggest that females modulate their investment in signalling according to the risk of remaining unmated and that they thereby economize on the costs associated with pheromone production and emission.

  4. Old maids have more appeal: effects of age and pheromone source on mate attraction in an orb-web spider

    Directory of Open Access Journals (Sweden)

    Anna-Lena Cory

    2016-04-01

    Full Text Available Background. In many insects and spider species, females attract males with volatile sex pheromones, but we know surprisingly little about the costs and benefits of female pheromone emission. Here, we test the hypothesis that mate attraction by females is dynamic and strategic in the sense that investment in mate attraction is matched to the needs of the female. We use the orb-web spider Argiope bruennichi in which females risk the production of unfertilised egg clutches if they do not receive a copulation within a certain time-frame. Methods. We designed field experiments to compare mate attraction by recently matured (young females with females close to oviposition (old. In addition, we experimentally separated the potential sources of pheromone transmission, namely the female body and the web silk. Results. In accordance with the hypothesis of strategic pheromone production, the probability of mate attraction and the number of males attracted differed between age classes. While the bodies and webs of young females were hardly found by males, the majority of old females attracted up to two males within two hours. Old females not only increased pheromone emission from their bodies but also from their webs. Capture webs alone spun by old females were significantly more efficient in attracting males than webs of younger females. Discussion. Our results suggest that females modulate their investment in signalling according to the risk of remaining unmated and that they thereby economize on the costs associated with pheromone production and emission.

  5. Pheromone disruption of Argentine ant trail integrity

    Science.gov (United States)

    Suckling, D.M.; Peck, R.W.; Manning, L.M.; Stringer, L.D.; Cappadonna, J.; El-Sayed, A. M.

    2008-01-01

    Disruption of Argentine ant trail following and reduced ability to forage (measured by bait location success) was achieved after presentation of an oversupply of trail pheromone, (Z)-9-hexadecenal. Experiments tested single pheromone point sources and dispersion of a formulation in small field plots. Ant walking behavior was recorded and digitized by using video tracking, before and after presentation of trail pheromone. Ants showed changes in three parameters within seconds of treatment: (1) Ants on trails normally showed a unimodal frequency distribution of walking track angles, but this pattern disappeared after presentation of the trail pheromone; (2) ants showed initial high trail integrity on a range of untreated substrates from painted walls to wooden or concrete floors, but this was significantly reduced following presentation of a point source of pheromone; (3) the number of ants in the pheromone-treated area increased over time, as recruitment apparently exceeded departures. To test trail disruption in small outdoor plots, the trail pheromone was formulated with carnuba wax-coated quartz laboratory sand (1 g quartz sand/0.2 g wax/1 mg pheromone). The pheromone formulation, with a half-life of 30 h, was applied by rotary spreader at four rates (0, 2.5, 7.5, and 25 mg pheromone/m2) to 1- and 4-m2 plots in Volcanoes National Park, Hawaii. Ant counts at bait cards in treated plots were significantly reduced compared to controls on the day of treatment, and there was a significant reduction in ant foraging for 2 days. These results show that trail pheromone disruption of Argentine ants is possible, but a much more durable formulation is needed before nest-level impacts can be expected. ?? 2008 Springer Science+Business Media, LLC.

  6. Inhibition of the Responses to Sex Pheromone of the Fall Armyworm, Spodoptera frugiperda

    Science.gov (United States)

    Malo, Edi A.; Rojas, Julio C.; Gago, Rafael; Guerrero, Ángel

    2013-01-01

    Trifluoromethyl ketones reversibly inhibit pheromone-degrading esterases in insect olfactory tissues, affecting pheromone detection and behavior of moth males. In this work, (Z)-9-tetradecenyl trifluoromethyl ketone (Z9-14:TFMK), a closely-related analogue of the pheromone of the fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), was prepared and tested in electroantennogram and field tests as possible inhibitors of the pheromone action. The electroantennogram parameters, amplitude, and the repolarization time of the antennal responses of S. frugiperda males were affected by Z9-14:TFMK vapors. Exposure of male antennae to a stream of air passing through 100 ìg of the ketone produced a significant reduction of the amplitude and an increase of 2/3 repolarization time signals to the pheromone. The effect was reversible and dose-dependent. In the field, the analogue significantly decreased the number of males caught when mixed with the pheromone in 10:1 ratio. The results suggest that Z9-14:TFMK is a mating disruptant of S. frugiperda and may be a good candidate to consider in future strategies to control this pest. PMID:24766416

  7. Structure-Activity Relationship of α Mating Pheromone from the Fungal Pathogen Fusarium oxysporum.

    Science.gov (United States)

    Vitale, Stefania; Partida-Hanon, Angélica; Serrano, Soraya; Martínez-Del-Pozo, Álvaro; Di Pietro, Antonio; Turrà, David; Bruix, Marta

    2017-03-03

    During sexual development ascomycete fungi produce two types of peptide pheromones termed a and α. The α pheromone from the budding yeast Saccharomyces cerevisiae , a 13-residue peptide that elicits cell cycle arrest and chemotropic growth, has served as paradigm for the interaction of small peptides with their cognate G protein-coupled receptors. However, no structural information is currently available for α pheromones from filamentous ascomycetes, which are significantly shorter and share almost no sequence similarity with the S. cerevisiae homolog. High resolution structure of synthetic α-pheromone from the plant pathogenic ascomycete Fusarium oxysporum revealed the presence of a central β-turn resembling that of its yeast counterpart. Disruption of the-fold by d-alanine substitution of the conserved central Gly 6 -Gln 7 residues or by random sequence scrambling demonstrated a crucial role for this structural determinant in chemoattractant activity. Unexpectedly, the growth inhibitory effect of F. oxysporum α-pheromone was independent of the cognate G protein-coupled receptors Ste2 and of the central β-turn but instead required two conserved Trp 1 -Cys 2 residues at the N terminus. These results indicate that, despite their reduced size, fungal α-pheromones contain discrete functional regions with a defined secondary structure that regulate diverse biological processes such as polarity reorientation and cell division. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  8. A novel mechanism regulating a sexual signal: the testosterone-based inhibition of female sex pheromone expression in garter snakes.

    Science.gov (United States)

    Parker, M Rockwell; Mason, Robert T

    2014-08-01

    Vertebrates communicate their sex to conspecifics through the use of sexually dimorphic signals, such as ornaments, behaviors and scents. Furthermore, the physiological connection between hormones and secondary sexual signal expression is key to understanding their dimorphism, seasonality and evolution. The red-sided garter snake (Thamnophis sirtalis parietalis) is the only reptile for which a described pheromone currently exists, and because garter snakes rely completely on the sexual attractiveness pheromone for species identification and mate choice, they constitute a unique model species for exploring the relationship between pheromones and the endocrine system. We recently demonstrated that estrogen can activate female pheromone production in male garter snakes. The purpose of this study was to determine the mechanism(s) acting to prevent female pheromone production in males. We found that castrated males (GX) are courted by wild males in the field and produce appreciable amounts of female sex pheromone. Furthermore, pheromone production is inhibited in castrates given testosterone implants (GX+T), suggesting that pheromone production is actively inhibited by the presence of testosterone. Lastly, testosterone supplementation alone (T) increased the production of several saturated methyl ketones in the pheromone but not the unsaturated ketones; this may indicate that saturated ketones are testosterone-activated components of the garter snake's skin lipid milieu. Collectively, our research has shown that pheromone expression in snakes results from two processes: activation by the feminizing steroid estradiol and inhibition by testosterone. We suggest that basal birds and garter snakes share common pathways of activation that modulate crucial intraspecific signals that originate from skin. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Volatile compounds profile and sensory evaluation of Beninese condiments produced by inocula of Bacillus subtilis

    DEFF Research Database (Denmark)

    Azokpota, Paulin; Hounhouigan, Joseph D.; Annan, Nana T.

    2010-01-01

    in high number and in concentrations which varied according to the inoculum of B. subtilis used. The condiments produced with starter cultures scored significantly (P ... was similar.   CONCLUSION: The investigated B. subtilis, BS1, BS2 and BS3 can be considered as potential starter cultures for the fermentation of African locust beans to produce good quality of Beninese food condiments. Copyright © 2009 Society of Chemical Industry...

  10. Moths behaving like butterflies. Evolutionary loss of long range attractant pheromones in castniid moths: a Paysandisia archon model.

    Science.gov (United States)

    Sarto i Monteys, Víctor; Acín, Patricia; Rosell, Glòria; Quero, Carmen; Jiménez, Miquel A; Guerrero, Angel

    2012-01-01

    In the course of evolution butterflies and moths developed two different reproductive behaviors. Whereas butterflies rely on visual stimuli for mate location, moths use the 'female calling plus male seduction' system, in which females release long-range sex pheromones to attract conspecific males. There are few exceptions from this pattern but in all cases known female moths possess sex pheromone glands which apparently have been lost in female butterflies. In the day-flying moth family Castniidae ("butterfly-moths"), which includes some important crop pests, no pheromones have been found so far. Using a multidisciplinary approach we described the steps involved in the courtship of P. archon, showing that visual cues are the only ones used for mate location; showed that the morphology and fine structure of the antennae of this moth are strikingly similar to those of butterflies, with male sensilla apparently not suited to detect female-released long range pheromones; showed that its females lack pheromone-producing glands, and identified three compounds as putative male sex pheromone (MSP) components of P. archon, released from the proximal halves of male forewings and hindwings. This study provides evidence for the first time in Lepidoptera that females of a moth do not produce any pheromone to attract males, and that mate location is achieved only visually by patrolling males, which may release a pheromone at short distance, putatively a mixture of Z,E-farnesal, E,E-farnesal, and (E,Z)-2,13-octadecadienol. The outlined behavior, long thought to be unique to butterflies, is likely to be widespread in Castniidae implying a novel, unparalleled butterfly-like reproductive behavior in moths. This will also have practical implications in applied entomology since it signifies that the monitoring/control of castniid pests should not be based on the use of female-produced pheromones, as it is usually done in many moths.

  11. A reference gene set for sex pheromone biosynthesis and degradation genes from the diamondback moth, Plutella xylostella, based on genome and transcriptome digital gene expression analyses.

    Science.gov (United States)

    He, Peng; Zhang, Yun-Fei; Hong, Duan-Yang; Wang, Jun; Wang, Xing-Liang; Zuo, Ling-Hua; Tang, Xian-Fu; Xu, Wei-Ming; He, Ming

    2017-03-01

    Female moths synthesize species-specific sex pheromone components and release them to attract male moths, which depend on precise sex pheromone chemosensory system to locate females. Two types of genes involved in the sex pheromone biosynthesis and degradation pathways play essential roles in this important moth behavior. To understand the function of genes in the sex pheromone pathway, this study investigated the genome-wide and digital gene expression of sex pheromone biosynthesis and degradation genes in various adult tissues in the diamondback moth (DBM), Plutella xylostella, which is a notorious vegetable pest worldwide. A massive transcriptome data (at least 39.04 Gb) was generated by sequencing 6 adult tissues including male antennae, female antennae, heads, legs, abdomen and female pheromone glands from DBM by using Illumina 4000 next-generation sequencing and mapping to a published DBM genome. Bioinformatics analysis yielded a total of 89,332 unigenes among which 87 transcripts were putatively related to seven gene families in the sex pheromone biosynthesis pathway. Among these, seven [two desaturases (DES), three fatty acyl-CoA reductases (FAR) one acetyltransferase (ACT) and one alcohol dehydrogenase (AD)] were mainly expressed in the pheromone glands with likely function in the three essential sex pheromone biosynthesis steps: desaturation, reduction, and esterification. We also identified 210 odorant-degradation related genes (including sex pheromone-degradation related genes) from seven major enzyme groups. Among these genes, 100 genes are new identified and two aldehyde oxidases (AOXs), one aldehyde dehydrogenase (ALDH), five carboxyl/cholinesterases (CCEs), five UDP-glycosyltransferases (UGTs), eight cytochrome P450 (CYP) and three glutathione S-transferases (GSTs) displayed more robust expression in the antennae, and thus are proposed to participate in the degradation of sex pheromone components and plant volatiles. To date, this is the most

  12. The male sex pheromone of the butterfly Bicyclus anynana: towards an evolutionary analysis.

    Directory of Open Access Journals (Sweden)

    Caroline M Nieberding

    Full Text Available BACKGROUND: Female sex pheromones attracting mating partners over long distances are a major determinant of reproductive isolation and speciation in Lepidoptera. Males can also produce sex pheromones but their study, particularly in butterflies, has received little attention. A detailed comparison of sex pheromones in male butterflies with those of female moths would reveal patterns of conservation versus novelty in the associated behaviours, biosynthetic pathways, compounds, scent-releasing structures and receiving systems. Here we assess whether the African butterfly Bicyclus anynana, for which genetic, genomic, phylogenetic, ecological and ethological tools are available, represents a relevant model to contribute to such comparative studies. METHODOLOGY/PRINCIPAL FINDINGS: Using a multidisciplinary approach, we determined the chemical composition of the male sex pheromone (MSP in the African butterfly B. anynana, and demonstrated its behavioural activity. First, we identified three compounds forming the presumptive MSP, namely (Z-9-tetradecenol (Z9-14:OH, hexadecanal (16:Ald and 6,10,14-trimethylpentadecan-2-ol (6,10,14-trime-15-2-ol, and produced by the male secondary sexual structures, the androconia. Second, we described the male courtship sequence and found that males with artificially reduced amounts of MSP have a reduced mating success in semi-field conditions. Finally, we could restore the mating success of these males by perfuming them with the synthetic MSP. CONCLUSIONS/SIGNIFICANCE: This study provides one of the first integrative analyses of a MSP in butterflies. The toolkit it has developed will enable the investigation of the type of information about male quality that is conveyed by the MSP in intraspecific communication. Interestingly, the chemical structure of B. anynana MSP is similar to some sex pheromones of female moths making a direct comparison of pheromone biosynthesis between male butterflies and female moths relevant

  13. Aphid wing induction and ecological costs of alarm pheromone emission under field conditions.

    Directory of Open Access Journals (Sweden)

    Eduardo Hatano

    2010-06-01

    Full Text Available The pea aphid, Acyrthosiphon pisum Harris, (Homoptera: Aphididae releases the volatile sesquiterpene (E-beta-farnesene (EBF when attacked by a predator, triggering escape responses in the aphid colony. Recently, it was shown that this alarm pheromone also mediates the production of the winged dispersal morph under laboratory conditions. The present work tested the wing-inducing effect of EBF under field conditions. Aphid colonies were exposed to two treatments (control and EBF and tested in two different environmental conditions (field and laboratory. As in previous experiments aphids produced higher proportion of winged morphs among their offspring when exposed to EBF in the laboratory but even under field conditions the proportion of winged offspring was higher after EBF application (6.84+/-0.98% compared to the hexane control (1.54+/-0.25%. In the field, the proportion of adult aphids found on the plant at the end of the experiment was lower in the EBF treatment (58.1+/-5.5% than in the control (66.9+/-4.6%, in contrast to the climate chamber test where the numbers of adult aphids found on the plant at the end of the experiment were, in both treatments, similar to the numbers put on the plant initially. Our results show that the role of EBF in aphid wing induction is also apparent under field conditions and they may indicate a potential cost of EBF emission. They also emphasize the importance of investigating the ecological role of induced defences under field conditions.

  14. Pheromones in White Pine Cone Beetle, Conophthorus coniperdu (Schwarz) (Coleoptera: Scolytidae)

    Science.gov (United States)

    Goran Birgersson; Gary L. DeBarr; Peter de Groot; Mark J. Dalusky; Harold D. Pierce; John H. Borden; Holger Meyer; Wittko Francke; Karl E. Espelie; C. Wayne Berisford

    1995-01-01

    Female white pine cone beetles, Conophrhorus coniperda, attacking second-year cones of eastern white pine, Pinus strobus L., produced a sex-specific pheromone that attracted conspecific males in laboratory bioassays and to field traps. Beetle response was enhanced by host monoterpenes. The female-produced compound was identified in...

  15. Characterization of an Aggregation Pheromone in Hylesinus pruinosus (Coleoptera: Curculionidae: Scolytinae)

    Science.gov (United States)

    William Shepherd; Brian Sullivan; Bradley Hoosier; JoAnne Barrett; Tessa Bauman

    2010-01-01

    We conducted laboratory and field bioassays to characterize the pheromone system of an ash bark beetle, Hylesinus pruinosus Eichhoff (Coleoptera: Curculionidae: Scolytinae). Solitary females in newly initiated galleries in ash logs produced (+)-exo-brevicomin, whereas male beetles paired with females produced (+)-endo-brevicomin, lesser quantities of...

  16. Identification and Characterization of Pheromone Receptors and Interplay between Receptors and Pheromone Binding Proteins in the Diamondback Moth, Plutella xyllostella

    OpenAIRE

    Sun, Mengjing; Liu, Yang; Walker, William B.; Liu, Chengcheng; Lin, Kejian; Gu, Shaohua; Zhang, Yongjun; Zhou, Jingjiang; Wang, Guirong

    2013-01-01

    Moths depend on olfactory cues such as sex pheromones to find and recognize mating partners. Pheromone receptors (PRs) and Pheromone binding proteins (PBPs) are thought to be associated with olfactory signal transduction of pheromonal compounds in peripheral olfactory reception. Here six candidate pheromone receptor genes in the diamondback moth, Plutella xyllostella were identified and cloned. All of the six candidate PR genes display male-biased expression, which is a typical characteristic...

  17. Pheromone discrimination by a pH-tuned polymorphism of the Bombyx mori pheromone-binding protein

    OpenAIRE

    Damberger, Fred F.; Michel, Erich; Ishida, Yuko; Leal, Walter S.; Wüthrich, Kurt

    2013-01-01

    Pheromone recognition by insect olfactory organs is critical for the ability of insects to locate mates. The silkworm moth Bombyx mori has long served as a model organism for studies of this process. Key components in the sensory organs have been identified, including the pheromone bombykol, pheromone-binding protein (BmorPBP), ligand-degrading enzymes, and the pheromone receptor, but many details of the mechanism allowing highly sensitive and selective pheromone detection are still elusive. ...

  18. Oil and stock market volatility: A multivariate stochastic volatility perspective

    International Nuclear Information System (INIS)

    Vo, Minh

    2011-01-01

    This paper models the volatility of stock and oil futures markets using the multivariate stochastic volatility structure in an attempt to extract information intertwined in both markets for risk prediction. It offers four major findings. First, the stock and oil futures prices are inter-related. Their correlation follows a time-varying dynamic process and tends to increase when the markets are more volatile. Second, conditioned on the past information, the volatility in each market is very persistent, i.e., it varies in a predictable manner. Third, there is inter-market dependence in volatility. Innovations that hit either market can affect the volatility in the other market. In other words, conditioned on the persistence and the past volatility in their respective markets, the past volatility of the stock (oil futures) market also has predictive power over the future volatility of the oil futures (stock) market. Finally, the model produces more accurate Value-at-Risk estimates than other benchmarks commonly used in the financial industry. - Research Highlights: → This paper models the volatility of stock and oil futures markets using the multivariate stochastic volatility model. → The correlation between the two markets follows a time-varying dynamic process which tends to increase when the markets are more volatile. → The volatility in each market is very persistent. → Innovations that hit either market can affect the volatility in the other market. → The model produces more accurate Value-at-Risk estimates than other benchmarks commonly used in the financial industry.

  19. Sex Pheromone of the Cotton Mealybug, Phenacoccus solenopsis, with an Unusual Cyclobutane Structure.

    Science.gov (United States)

    Tabata, Jun; Ichiki, Ryoko T

    2016-11-01

    The cotton mealybug, Phenacoccus solenopsis, the distribution of which was formerly limited to Nearctic and Neotropical regions, recently invaded many countries in various regions including Asia, Africa, and the Pacific. More recently, P. solenopsis was newly recorded in Japan and is currently an emerging pest of agricultural crops. In this study, we determined the structure of a sex pheromone of P. solenopsis in order to develop an effective lure for monitoring this pest. From volatiles emitted by virgin adult females, we isolated a compound attractive to males. By means of coupled gas chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy, we identified this as (2,2-dimethyl-3-isopropylidenecyclobutyl)methyl 3-methylbut-2-enoate. This compound was synthesized and shown to be attractive to male P. solenopsis. Analysis by gas chromatography using an enantioselective stationary phase and polarimetry analyses of the natural pheromone and synthetic enantiomers showed the natural compound to be the (R)-(-)-enantiomer. This compound is an ester of maconelliol, which has an unusual cyclobutane structure found in sex pheromones of other mealybug species, and senecioic acid, also found in the pheromones of other mealybug species. However, this is the first example of the ester of maconelliol and senecioic acid as a natural product.

  20. SNMP is a signaling component required for pheromone sensitivity in Drosophila.

    Science.gov (United States)

    Jin, Xin; Ha, Tal Soo; Smith, Dean P

    2008-08-05

    The only known volatile pheromone in Drosophila, 11-cis-vaccenyl acetate (cVA), mediates a variety of behaviors including aggregation, mate recognition, and sexual behavior. cVA is detected by a small set of olfactory neurons located in T1 trichoid sensilla on the antennae of males and females. Two components known to be required for cVA reception are the odorant receptor Or67d and the extracellular pheromone-binding protein LUSH. Using a genetic screen for cVA-insensitive mutants, we have identified a third component required for cVA reception: sensory neuron membrane protein (SNMP). SNMP is a homolog of CD36, a scavenger receptor important for lipoprotein binding and uptake of cholesterol and lipids in vertebrates. In humans, loss of CD36 is linked to a wide range of disorders including insulin resistance, dyslipidemia, and atherosclerosis, but how CD36 functions in lipid transport and signal transduction is poorly understood. We show that SNMP is required in pheromone-sensitive neurons for cVA sensitivity but is not required for sensitivity to general odorants. Using antiserum to SNMP infused directly into the sensillum lymph, we show that SNMP function is required on the dendrites of cVA-sensitive neurons; this finding is consistent with a direct role in cVA signal transduction. Therefore, pheromone perception in Drosophila should serve as an excellent model to elucidate the role of CD36 members in transmembrane signaling.

  1. Development of a method to quantitate nematode pheromone for study of small-molecule metabolism in Caenorhabditis elegans.

    Science.gov (United States)

    Kim, Kwang-Youl; Joo, Hyoe-Jin; Kwon, Hye-Won; Kim, Heekyeong; Hancock, William S; Paik, Young-Ki

    2013-03-05

    Pheromones produced by Caenorhabditis elegans are considered key regulators of development, mating, and social behaviors in this organism. Here, we present a rapid mass spectrometry-based method (PheroQu) for absolute quantitation of nematode pheromones (e.g., daumone 1, 2, and 3) both in C. elegans worm bodies (as few as 20 worms) and in liquid culture medium. Pheromones were separated by ultra performance liquid chromatography and monitored by a positive electrospray ionization detector in the multiple-reaction monitoring mode. The daf-22 mutant worms were used as surrogate matrix for calibration, and stable deuterated isotope-containing pheromone was used as internal standard for measuring changes in pheromones in N2 wild-type and other strains under different growth conditions. The worm-body pheromones were extracted by acidified acetonitrile solvent, and the secreted pheromones were extracted from culture medium with solid-phase extraction cartridges. The run time was achieved in less than 2 min. The method was validated for specificity, linearity, accuracy, precision, recovery, and stability. The assay was linear over an amount range of 2-250 fmol, and the limit of quantitation was 2 fmol amounts for daumone 1, 2, and 3 in both worm bodies and culture medium. With the PheroQu method, we were able to identify the location of pheromone biosynthesis and determine the changes in different pheromone types synthesized, according to developmental stages and aging process. This method, which is simple, rapid, sensitive, and specific, will be useful for the study of small-molecule metabolism during developmental stages of C. elegans.

  2. Pest repellent properties of ant pheromones

    DEFF Research Database (Denmark)

    Offenberg, Joachim

    2012-01-01

    of ant pheromones may be sufficient to repel pest insects from ant territories. The study of ant semiochemicals is in its infancy, yet, evidence for their potential use in pest management is starting to build up. Pheromones from four of five tested ant species have been shown to deter herbivorous insect...... prey and competing ant species are also deterred by ant deposits, whereas ant symbionts may be attracted to them. Based on these promising initial findings, it seems advisable to further elucidate the signaling properties of ant pheromones and to test and develop their use in future pest management....

  3. Pheromone communication in amphibians and reptiles.

    Science.gov (United States)

    Houck, Lynne D

    2009-01-01

    This selective review considers herpetological papers that feature the use of chemical cues, particularly pheromones involved in reproductive interactions between potential mates. Primary examples include garter snake females that attract males, lacertid lizards and the effects of their femoral gland secretions, aquatic male newts that chemically attract females, and terrestrial salamander males that chemically persuade a female to mate. Each case study spans a number of research approaches (molecular, biochemical, behavioral) and is related to sensory processing and the physiological effects of pheromone delivery. These and related studies show that natural pheromones can be identified, validated with behavioral tests, and incorporated in research on vomeronasal functional response.

  4. Use of headspace SPME-GC-MS for the analysis of the volatiles produced by indoor molds grown on different substrates.

    Science.gov (United States)

    Van Lancker, Fien; Adams, An; Delmulle, Barbara; De Saeger, Sarah; Moretti, Antonio; Van Peteghem, Carlos; De Kimpe, Norbert

    2008-10-01

    An automated headspace solid phase microextraction method followed by GC-MS analysis was used to evaluate and compare the in vitro production of microbial volatile organic compounds (MVOCs) on malt extract agar, plasterboard and wallpaper. Five fungal strains were isolated from the walls of water-damaged houses and identified. In addition, four other common molds were studied. In general, MVOC production was the highest on malt extract agar. On this synthetic medium, molds typically produced 2-methylpropanol, 2-methylbutanol and 3-methylbutanol. On wallpaper, mainly 2-ethylhexanol, methyl 2-ethylhexanoate and compounds of the C8-complex such as 1-octene-3-ol, 3-octanone, 3-octanol and 1,3-octadiene were detected. The detection of 2-ethylhexanol and methyl 2-ethylhexanoate indicates an enhanced degradation of the substrate by most fungi. For growth on plasterboard, no typical metabolites were detected. Despite these metabolite differences on malt extract agar, wallpaper and plasterboard, some molds also produced specific compounds independently of the used substrate, such as trichodiene from Fusarium sporotrichioides and aristolochene from Penicillium roqueforti. Therefore, these metabolites can be used as markers for the identification and maybe also mycotoxin production of these molds. All five investigated Penicillium spp. in this study were able to produce two specific diterpenes, which were not produced by the other species studied. These two compounds, which remain unidentified until now, therefore seem specific for Penicillium spp. and are potentially interesting for the monitoring of this fungal genus. Further experiments will be performed with other Penicillium spp. to study the possibility that these two compounds are specific for this group of molds.

  5. Do perfume additives termed human pheromones warrant being termed pheromones?

    Science.gov (United States)

    Winman, Anders

    2004-09-30

    Two studies of the effects of perfume additives, termed human pheromones by the authors, have conveyed the message that these substances can promote an increase in human sociosexual behaviour [Physiol. Behav. 75 (2003) R1; Arch. Sex. Behav. 27 (1998) R2]. The present paper presents an extended analysis of this data. It is shown that in neither study is there a statistically significant increase in any of the sociosexual behaviours for the experimental groups. In the control groups of both studies, there are, however, moderate but statistically significant decreases in the corresponding behaviour. Most notably, there is no support in data for the claim that the substances increase the attractiveness of the wearers of the substances to the other sex. It is concluded that more research using matched homogenous groups of participants is needed. Copyright 2004 Elsevier Inc.

  6. Cross-generational impact of a male murine pheromone 2-sec-butyl-4,5-dihydrothiazole in female mice

    Science.gov (United States)

    Koyama, Sachiko; Soini, Helena A.; Wager-Miller, James; Alley, William R.; Pizzo, Matthew J.; Rodda, Cathleen; Alberts, Jeffrey; Crystal, Jonathon D.; Lai, Cary; Foley, John; Novotny, Milos V.

    2015-01-01

    The current understanding of the activity of mammalian pheromones is that endocrine and behavioural effects are limited to the exposed individuals. Here, we demonstrate that the nasal exposure of female mice to a male murine pheromone stimulates expansion of mammary glands, leading to prolonged nursing of pups. Subsequent behavioural testing of the pups from pheromone-exposed dams exhibited enhanced learning. Sialic acid components in the milk are known to be involved in brain development. We hypothesized that the offspring might have received more of this key nutrient that promotes brain development. The mRNA for polysialyltransferase, which produces polysialylated neural cell adhesion molecules related to brain development, was increased in the brain of offspring of pheromone-exposed dams at post-natal day 10, while it was not different at embryonic stages, indicating possible differential brain development during early post-natal life. PMID:26136453

  7. Pheromone Static Routing Strategy for Complex Networks

    Science.gov (United States)

    Hu, Mao-Bin; Henry, Y. K. Lau; Ling, Xiang; Jiang, Rui

    2012-12-01

    We adopt the concept of using pheromones to generate a set of static paths that can reach the performance of global dynamic routing strategy [Phys. Rev. E 81 (2010) 016113]. The path generation method consists of two stages. In the first stage, a pheromone is dropped to the nodes by packets forwarded according to the global dynamic routing strategy. In the second stage, pheromone static paths are generated according to the pheromone density. The output paths can greatly improve traffic systems' overall capacity on different network structures, including scale-free networks, small-world networks and random graphs. Because the paths are static, the system needs much less computational resources than the global dynamic routing strategy.

  8. Tissue localization and partial characterization of pheromone ...

    Indian Academy of Sciences (India)

    Unknown

    Female sex pheromone production in certain moth species have been shown to be regulated by a cephalic endo- crine peptidic .... A nitrogen laser (659 nm) was used as the desorption/ .... from the Council of Scientific and Industrial Research.

  9. Pheromone Production by an Invasive Bark Beetle Varies with Monoterpene Composition of its Naïve Host.

    Science.gov (United States)

    Taft, Spencer; Najar, Ahmed; Erbilgin, Nadir

    2015-06-01

    The secondary chemistry of host plants can have cascading impacts on the establishment of new insect herbivore populations, their long-term population dynamics, and their invasion potential in novel habitats. Mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae) has recently expanded its range into forests of jack pine, Pinus banksiana Lamb., in western Canada. We investigated whether variations in jack pine monoterpenes affect beetle pheromone production, as the primary components of the beetle's aggregation pheromone, (-)-trans-verbenol and anti-aggregation pheromone (-)-verbenone, are biosynthesized from the host monoterpene α-pinene. Jack pine bolts were collected from five Canadian provinces east of the beetle's current range, live D. ponderosae were introduced into them, and their monoterpene compositions were characterized. Production of (-)-trans-verbenol and (-)-verbenone emitted by beetles was measured to determine whether pheromone production varies with monoterpene composition of jack pines. Depending on particular ratios of major monoterpenes in host phloem, jack pine could be classified into three monoterpenoid groups characterized by high amounts of (+)-α-pinene, 3-carene, or a more moderate blend of monoterpenes, and beetle pheromone production varied among these groups. Specifically, beetles reared in trees characterized by high (+)-α-pinene produced the most (-)-trans-verbenol and (-)-verbenone, while beetles in trees characterized by high 3-carene produced the least. Our results indicate that pheromone production by D. ponderosae will remain a significant aspect and important predictor of its survival and persistence in the boreal forest.

  10. Fungal volatiles: Semiochemicals for stored-product beetles (Coleoptera: Cucujidae).

    Science.gov (United States)

    Pierce, A M; Pierce, H D; Borden, J H; Oehlschlager, A C

    1991-03-01

    Responses by five species of cucujid grain beetles (mixed-sex adults) to various volatiles were assessed by means of a two-choice, pitfall olfactometer. The test volatiles were short-chain alcohols and ketones known to be produced by fungi. Both racemic and chiral 1-octen-3-ols were strong attractants forCryptolestes ferrugineus (Stephens), as had been found previously forOryzaephilus surinamensis (L.),O. mercator (Fauvel), andAhasverus advena (Waltl). 3-Methylbutanol was another good attractant for these four cucujids, and it was the only test compound to whichCathartus quadricollis (Guér.) responded positively. 1-Octen-3-one, racemic 3-octanol, and 3-octanone showed various degrees of attractiveness for the former four species of cucujids.O. surinamensis was the only species of test beetle to show much positive response to 2-phenylethanol and ethanol. ForO. mercator andO. surinamensis, 3-methylbutanol enhanced positive response to their respective cucujolide aggregation pheromones.

  11. Evaluation of Volatile Organic Compounds and Carbonyl Compounds Present in the Cabins of Newly Produced, Medium- and Large-Size Coaches in China

    Directory of Open Access Journals (Sweden)

    Yan-Yang Lu

    2016-06-01

    Full Text Available An air-conditioned coach is an important form of transportation in modern motorized society; as a result, there is an increasing concern of in-vehicle air pollution. In this study, we aimed to identify and quantify the levels of volatile organic compounds (VOCs and carbonyl compounds (CCs in air samples collected from the cabins of newly produced, medium- and large-size coaches. Among the identified VOCs and CCs, toluene, ethylbenzene, xylene, formaldehyde, acetaldehyde, acrolein/acetone, and isovaleraldehyde were relatively abundant in the cabins. Time was found to affect the emissions of the contaminants in the coaches. Except for benzaldehyde, valeraldehyde and benzene, the highest in-vehicle concentrations of VOCs and CCs were observed on the 15th day after coming off the assembly line, and the concentrations exhibited an approximately inverted U-shaped pattern as a function of time. Interestingly, this study also showed that the interior temperature of the coaches significantly affected the VOCs emissions from the interior materials, whereas the levels of CCs were mainly influenced by the relative humidity within the coaches. In China, guidelines and regulations for the in-vehicle air quality assessment of the coaches have not yet been issued. The results of this study provide further understanding of the in-vehicle air quality of air-conditioned coaches and can be used in the development of both specific and general rules regarding medium- and large-size coaches.

  12. Production of Volatile Compounds in Reconstituted Milk Reduced-Fat Cheese and the Physicochemical Properties as Affected by Exopolysaccharide-Producing Strain

    Directory of Open Access Journals (Sweden)

    Weijun Wang

    2012-12-01

    Full Text Available The application of the exopolysaccharide-producing strains for improving the texture and technical properties of reduced-fat cheese looks very promising. Streptococcus thermophilus TM11 was evaluated for production of reduced-fat cheese using reconstituted milk powder (CRMP. The physicochemical analysis of fresh and stored cheeses showed that this strain slightly increased moisture content resulting in cheese with higher yield and lower protein content compared to the direct acidified cheese. The volatiles of cheese were determined by SPME and GC equipped with a mass spectrometer. The results indicated that the major compounds included aldehydes, ketones and acids, whereas, alcohols and branched-chain aldehydes that contribute to exciting and harsh flavors were not found in CRMP. By the textural profile analysis, we found the cheese made with S. thermophilus TM11 had lower cohesiveness, resilience and higher adhesiveness than the direct acidified cheese, and had similar hardness. Further, S. thermophilus TM11 greatly changed the protein matrix with more opened cavities according to observation by scanning electron microscopy. Consequently, use of S. thermophilus TM11 could endow CRMP with the novel and suitable flavor properties and improved texture quality.

  13. Evidence of an aggregation pheromone in the flea beetle,Phyllotreta Cruciferae (Goeze) (Coleoptera: Chrysomelidae).

    Science.gov (United States)

    Peng, C; Weiss, M J

    1992-06-01

    Laboratory olfactometer bioassays and field trapping experiments showed that the flea beetle,Phyllotreta cruciferae (Goeze), was highly attracted by oilseed rape(Brassica napus L.) when flea beetles were on the plant. This attraction was mediated by a flea beetle-produced aggregation pheromone based upon: (1) Oilseed rape damaged mechanically, or byP. cruciferae, or by diamondback moth,Plutella xylostella (L.), did not attractP. cruciferae. (2) Contact with the plants or feeding was required for the production of aggregation pheromone because oilseed rape alone was not attractive when separated from flea beetles by a screen. (3) Equal numbers of males and females were attracted.

  14. Sex Pheromone and Trail Pheromone of the Sand Termite Psammotermes hybostoma

    Czech Academy of Sciences Publication Activity Database

    Sillam-Dusses, David; Hanus, Robert; Abd El-Latif, A. O.; Jiroš, Pavel; Krasulová, Jana; Kalinová, Blanka; Valterová, Irena; Šobotník, Jan

    2011-01-01

    Roč. 37, č. 2 (2011), s. 179-188 ISSN 0098-0331 R&D Projects: GA ČR GAP506/10/1570 Institutional research plan: CEZ:AV0Z40550506 Keywords : sex pheromone * trail pheromone * Psammotermes hybostoma * termites * Rhinotermitidae Subject RIV: CC - Organic Chemistry Impact factor: 2.657, year: 2011

  15. Intercellular signaling in Stigmatella aurantiaca: purification and characterization of stigmolone, a myxobacterial pheromone.

    Science.gov (United States)

    Plaga, W; Stamm, I; Schairer, H U

    1998-09-15

    The myxobacterium Stigmatella aurantiaca passes through a life cycle that involves formation of a multicellular fruiting body as the most complex stage. An early step in this differentiation process depends on a signal factor secreted by the cells when nutrients become limited. The formation of a fruiting body from a small cell population can be accelerated by addition of this secreted material. The bioactive compound was found to be steam volatile. It was purified to homogeneity by steam distillation followed by reversed-phase and normal-phase HPLC. The pheromone was named stigmolone, in accordance with the structure 2,5, 8-trimethyl-8-hydroxy-nonan-4-one, as determined by NMR and mass spectrometry. Stigmolone represents a structurally unique and highly bioactive prokaryotic pheromone that is effective in the bioassay at 1 nM concentration.

  16. A sex pheromone receptor in the Hessian fly Mayetiola destructor (Diptera, Cecidomyiidae

    Directory of Open Access Journals (Sweden)

    Martin N. Andersson

    2016-09-01

    Full Text Available The Hessian fly, Mayetiola destructor Say (Diptera, Cecidomyiidae, is a pest of wheat and belongs to a group of gall-inducing herbivores. This species has a unique life history and several ecological features that differentiate it from other Diptera such as Drosophila melanogaster and blood-feeding mosquitoes. These features include a short, non-feeding adult life stage (1-2 days and the use of a long-range sex pheromone produced and released by adult females. Sex pheromones are detected by members of the odorant receptor (OR family within the Lepidoptera, but no receptors for similar long-range sex pheromones have been characterized from the Diptera. Previously, 122 OR genes have been annotated from the Hessian fly genome, with many of them showing sex-biased expression in the antennae. Here we have expressed, in HEK293 cells, five MdesORs that display male-biased expression in antennae, and we have identified MdesOR115 as a Hessian fly sex pheromone receptor. MdesOR115 responds primarily to the sex pheromone component (2S,8E,10E-8,10-tridecadien-2-yl acetate, and secondarily to the corresponding Z,E-isomer. Certain sensory neuron membrane proteins (i.e., SNMP1 are important for responses of pheromone receptors in flies and moths. The Hessian fly genome is unusual in that it encodes six SNMP1 paralogues, of which five are expressed in antennae. We co-expressed each of the five antennal SNMP1 paralogues together with each of the five candidate sex pheromone receptors from the Hessian fly and found that they do not influence the response of MdesOR115, nor do they confer responsiveness in any of the non-responsive ORs to any of the sex pheromone components identified to date in the Hessian fly. Using Western blots, we detected protein expression of MdesOrco, all MdesSNMPs, and all MdesORs except for MdesOR113, potentially explaining the lack of response from this OR. In conclusion, we report the first functional characterization of an OR from the

  17. Pheromone-induced priming of a defensive response in Western flower thrips

    NARCIS (Netherlands)

    de Bruijn, P.J.A.; Egas, M.; Janssen, A.; Sabelis, M.W.

    2006-01-01

    Abstract The Western flower thrips Frankliniella occidentalis produces conspicuous anal droplets that function as a direct defense against various predators. These droplets also function in pheromonal communication in that they contain a mixture of decyl acetate and dodecyl acetate, which acts as an

  18. Volatility Discovery

    DEFF Research Database (Denmark)

    Dias, Gustavo Fruet; Scherrer, Cristina; Papailias, Fotis

    The price discovery literature investigates how homogenous securities traded on different markets incorporate information into prices. We take this literature one step further and investigate how these markets contribute to stochastic volatility (volatility discovery). We formally show...... that the realized measures from homogenous securities share a fractional stochastic trend, which is a combination of the price and volatility discovery measures. Furthermore, we show that volatility discovery is associated with the way that market participants process information arrival (market sensitivity......). Finally, we compute volatility discovery for 30 actively traded stocks in the U.S. and report that Nyse and Arca dominate Nasdaq....

  19. Determination of volatiles produced during radiation processing in food and medicinal herbs; Determinacao de volateis produzidos durante o processamento por radiacao em ervas alimenticias e medicinais

    Energy Technology Data Exchange (ETDEWEB)

    Salum, Debora Christina

    2008-07-01

    In order to protect food from pathogenic microorganisms as well as to increase its shelf life while keeping sensorial properties (e.g. odor and taste), once the latter are one of the main properties required by spice buyers, it is necessary to analyze volatile formation from irradiation of medicinal and food herbs. The aim of the present study was to analyze volatile formation from Co irradiation of Laurus Cinnamomum, Piper Nigrum, Origanum Vulgare and Myristica Fragans. Possible changes on the odor of these herbs are evaluated by characterizing different radiation doses and effects on sensorial properties in order to allow better application of irradiation technology. l he samples have been irradiated in plastic packages by making use of a {sup 60}Co Gamma irradiator. Irradiation doses of 0, 5, 10, 15, 20 and 25kGy have been tested. For the analysis of the samples, SPME has been applied, while for the analysis of volatile compounds, CG/MS. Spice irradiation has promoted mostly decrease in volatile compounds when doses of 5, 10, 15, 20 and 25kGy were used. For Laurus cinnamomum, the irradiation decreased volatile by nearly 56% and 89.5% respectively, comparing to volatile from a sample which has not been previously irradiated. Differently from other spices analyzed, irradiation on Myristica Fragans has increased volatile compounds except for 4-terpineol. The miristicine (toxic substance when in large quantities, commonly mentioned as narcotic) has increased by nearly 80%. For Origanum Vulgare and Piper Nigrum, significant decrease in volatile compounds have been found, mainly when it comes to 25 kGy irradiation. In general, results indicate loss of sensorial quality of spices. (author)

  20. Evidence for a Nest Defense Pheromone in Bald-Faced Hornets, Dolichovespula Maculata, and Identification of Components.

    Science.gov (United States)

    Jimenez, Sebastian Ibarra; Gries, Regine; Zhai, Huimin; Derstine, Nathan; McCann, Sean; Gries, Gerhard

    2016-05-01

    In eusocial insects like Bald-faced hornets, Dolichovespula maculata, nest defense is essential because nests contain a large number of protein-rich larvae and pupae, and thus are attractive to nest predators. Our objectives were to investigate whether D. maculata exhibit pheromone-mediated nest defense, and to identify and field test any pheromone components. We tested for pheromone-mediated nest defense behavior of D. maculata by placing a paired box-apparatus near the entrance of D. maculata nests, and treating both boxes with a solvent control, or one of the two boxes with a solvent control and the other with either venom sac extract, the putative source of nest defense pheromone, or synthetic pheromone. The sound impulses caused by nest mates attempting to sting or strike the boxes were recorded for 3 min. Compared to the double-control treatment, the number of strikes increased 27-fold when one of the two boxes was treated with venom sac extract, providing evidence for an alarm response. The box treated with venom sac extract also induced a significantly greater proportion of strikes than the corresponding control box, providing evidence for a target-oriented response. Analyzing venom sac extract by gas chromatographic-electroantennographic detection (GC-EAD) and GC-mass spectrometry resulted in the identification of seven candidate pheromone components: (a) dimethylaminoethanol, (b) dimethylamino ethyl acetate, (c) 2,5-dimethylpyrazine, (d) N-3-methylbutylacetamide, (e) 2-heptadecanone, (f) (Z)-8-heptadecen-2-one, and (g) (Z)-10-nonadecen-2-one. Testing in paired-box bioassays blends of the nitrogen-containing volatile components a-d, the less volatile ketones e-g, or both (a-g), indicated that a-d primarily have an alarm function. The ketones e-g, in contrast, induced target-oriented responses, possibly marking the box, or potential nest predators, for guided and concerted attacks, or enhancing the alarm-inducing effect of the volatile pheromone components

  1. Advances in Attract-and-Kill for Agricultural Pests: Beyond Pheromones.

    Science.gov (United States)

    Gregg, Peter C; Del Socorro, Alice P; Landolt, Peter J

    2018-01-07

    Attract-and-kill has considerable potential as a tactic in integrated management of pests of agricultural crops, but the use of sex pheromones as attractants is limited by male multiple mating and immigration of mated females into treated areas. Attractants for both sexes, and particularly females, would minimize these difficulties. Volatile compounds derived from plants or fermentation of plant products can attract females and have been used in traps for monitoring and control, and in sprayable attract-and-kill formulations or bait stations. Recent advances in fundamental understanding of insect responses to plant volatiles should contribute to the development of products that can help manage a wide range of pests with few impacts on nontarget organisms, but theory must be tempered with pragmatism in the selection of volatiles and toxicants and in defining their roles in formulations. Market requirements and regulatory factors must be considered in parallel with scientific constraints if successful products are to be developed.

  2. Pheromone communication in the fission yeast Schizosaccharomyces pombe

    DEFF Research Database (Denmark)

    Nielsen, O; Davey, William John; Nielsen, Olaf

    1995-01-01

    Conjugation between two haploid yeast cells is generally controlled by the reciprocal action of diffusible mating pheromones, cells of each mating type releasing pheromones that induce mating-specific changes in cells of the opposite type. Recent studies into pheromone signalling in the fission...

  3. Various Bee Pheromones Binding Affinity, Exclusive Chemosensillar Localization, and Key Amino Acid Sites Reveal the Distinctive Characteristics of Odorant-Binding Protein 11 in the Eastern Honey Bee, Apis cerana.

    Science.gov (United States)

    Song, Xin-Mi; Zhang, Lin-Ya; Fu, Xiao-Bin; Wu, Fan; Tan, Jing; Li, Hong-Liang

    2018-01-01

    Odorant-binding proteins (OBPs) are the critical elements responsible for binding and transporting odors and pheromones in the sensitive olfactory system in insects. Honey bees are representative social insects that have complex odorants and pheromone communication systems relative to solitary insects. Here, we first cloned and characterized OBP11 ( AcerOBP11 ), from the worker bees antennae of Eastern honey bee, Apis cerana . Based on sequence and phylogenetic analysis, most sequences homologous to AcerOBP11 belong to the typical OBPs family. The transcriptional expression profiles showed that AcerOBP11 was expressed throughout the developmental stages and highly specifically expressed in adult antennae. Using immunofluorescence localization, AcerOBP11 in worker bee's antennae was only localized in the sensilla basiconica (SB) near the fringe of each segment. Fluorescence ligand-binding assay showed that AcerOBP11 protein had strong binding affinity with the tested various bee pheromones components, including the main queen mandibular pheromones (QMPs), methyl p-hydroxybenzoate (HOB), and ( E )-9-oxo-2-decanoic acid (9-ODA), alarm pheromone (n-hexanol), and worker pheromone components. AcerOBP11 also had strong binding affinity to plant volatiles, such as 4-Allylveratrole. Based on the docking and site-directed mutagenesis, two key amino acid residues (Ile97 and Ile140) were involved in the binding of AcerOBP11 to various bee pheromones. Taken together, we identified that AcerOBP11 was localized in a single type of antennal chemosensilla and had complex ligand-binding properties, which confer the dual-role with the primary characteristics of sensing various bee pheromones and secondary characteristics of sensing general odorants. This study not only prompts the theoretical basis of OBPs-mediated bee pheromones recognition of honey bee, but also extends the understanding of differences in pheromone communication between social and solitary insects.

  4. Various Bee Pheromones Binding Affinity, Exclusive Chemosensillar Localization, and Key Amino Acid Sites Reveal the Distinctive Characteristics of Odorant-Binding Protein 11 in the Eastern Honey Bee, Apis cerana

    Directory of Open Access Journals (Sweden)

    Xin-Mi Song

    2018-04-01

    Full Text Available Odorant-binding proteins (OBPs are the critical elements responsible for binding and transporting odors and pheromones in the sensitive olfactory system in insects. Honey bees are representative social insects that have complex odorants and pheromone communication systems relative to solitary insects. Here, we first cloned and characterized OBP11 (AcerOBP11, from the worker bees antennae of Eastern honey bee, Apis cerana. Based on sequence and phylogenetic analysis, most sequences homologous to AcerOBP11 belong to the typical OBPs family. The transcriptional expression profiles showed that AcerOBP11 was expressed throughout the developmental stages and highly specifically expressed in adult antennae. Using immunofluorescence localization, AcerOBP11 in worker bee's antennae was only localized in the sensilla basiconica (SB near the fringe of each segment. Fluorescence ligand-binding assay showed that AcerOBP11 protein had strong binding affinity with the tested various bee pheromones components, including the main queen mandibular pheromones (QMPs, methyl p-hydroxybenzoate (HOB, and (E-9-oxo-2-decanoic acid (9-ODA, alarm pheromone (n-hexanol, and worker pheromone components. AcerOBP11 also had strong binding affinity to plant volatiles, such as 4-Allylveratrole. Based on the docking and site-directed mutagenesis, two key amino acid residues (Ile97 and Ile140 were involved in the binding of AcerOBP11 to various bee pheromones. Taken together, we identified that AcerOBP11 was localized in a single type of antennal chemosensilla and had complex ligand-binding properties, which confer the dual-role with the primary characteristics of sensing various bee pheromones and secondary characteristics of sensing general odorants. This study not only prompts the theoretical basis of OBPs-mediated bee pheromones recognition of honey bee, but also extends the understanding of differences in pheromone communication between social and solitary insects.

  5. Identification of the pheromone biosynthesis genes from the sex pheromone gland transcriptome of the diamondback moth, Plutella xylostella.

    Science.gov (United States)

    Chen, Da-Song; Dai, Jian-Qing; Han, Shi-Chou

    2017-11-24

    The diamondback moth was estimated to increase costs to the global agricultural economy as the global area increase of Brassica vegetable crops and oilseed rape. Sex pheromones traps are outstanding tools available in Integrated Pest Management for many years and provides an effective approach for DBM population monitoring and control. The ratio of two major sex pheromone compounds shows geographical variations. However, the limitation of our information in the DBM pheromone biosynthesis dampens our understanding of the ratio diversity of pheromone compounds. Here, we constructed a transcriptomic library from the DBM pheromone gland and identified genes putatively involved in the fatty acid biosynthesis, pheromones functional group transfer, and β-oxidation enzymes. In addition, odorant binding protein, chemosensory protein and pheromone binding protein genes encoded in the pheromone gland transcriptome, suggest that female DBM moths may receive odors or pheromone compounds via their pheromone gland and ovipositor system. Tissue expression profiles further revealed that two ALR, three DES and one FAR5 genes were pheromone gland tissue biased, while some chemoreception genes expressed extensively in PG, pupa, antenna and legs tissues. Finally, the candidate genes from large-scale transcriptome information may be useful for characterizing a presumed biosynthetic pathway of the DBM sex pheromone.

  6. Identification of an intraspecific alarm pheromone and two conserved odorant-binding proteins associated with (E)-β-farnesene perception in aphid Rhopalosiphum padi.

    Science.gov (United States)

    Fan, Jia; Xue, Wenxin; Duan, Hongxia; Jiang, Xin; Zhang, Yong; Yu, Wenjuan; Jiang, Shanshan; Sun, Jingrun; Chen, Julian

    2017-08-01

    (E)-β-farnesene (EBF) is the common active component of aphid alarm pheromone. Either or both of two orthologs of ordorant-binding proteins (OBPs), OBP3 and OBP7, recently reported in aphids, may be involved in EBF perception. The aim of this study was to investigate the respondence of the aphid Rhopalosiphum padi to its intraspecific alarm pheromone and which OBP is responsible for that response. We tested the olfactory response of the aphid R. padi to EBF and freshly crushed aphids. Then, we extracted the volatiles from crushed aphids using solid phase microextraction (SPME) for analysis with GC×GC-TOF/MS. We also cloned two OBPs cDNAs in R. padi (RpadOBP3 and RpadOBP7) and expressed them in competent Escherichia coli cells. Both recombinant proteins, RpadOBP3 and RpadOBP7, bound EBF well, with RpadOBP7 having specifically stronger affinity for EBF than for other volatiles. Based on the crystal structure of the OBPs with high identity, we performed homology modeling and analyzed the interactions between RpadOBPs and EBF. In conclusion, R. padi was repelled by both EBF and crushed aphids. EBF was identified as the only volatile that acted as the alarm pheromone. Our results indicated that OBP7 is a potential molecular target to control wheat aphids by disturbing their behaviors to the alarm pheromone. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Virtual volatility

    Science.gov (United States)

    Silva, A. Christian; Prange, Richard E.

    2007-03-01

    We introduce the concept of virtual volatility. This simple but new measure shows how to quantify the uncertainty in the forecast of the drift component of a random walk. The virtual volatility also is a useful tool in understanding the stochastic process for a given portfolio. In particular, and as an example, we were able to identify mean reversion effect in our portfolio. Finally, we briefly discuss the potential practical effect of the virtual volatility on an investor asset allocation strategy.

  8. Pest repelling properties of ant pheromones

    DEFF Research Database (Denmark)

    Offenberg, Joachim

    2014-01-01

    Ants control pests via predation and physical deterrence; however, ant communication is based on chemical cues which may serve as warning signals to potential prey and other intruders. The presence of ant pheromones may, thus, be sufficient to repel pests from ant territories. This mini-review sh......-review shows that four out of five tested ant species deposit pheromones that repel herbivorous prey from their host plants.......Ants control pests via predation and physical deterrence; however, ant communication is based on chemical cues which may serve as warning signals to potential prey and other intruders. The presence of ant pheromones may, thus, be sufficient to repel pests from ant territories. This mini...

  9. Pheromones: a new ergogenic aid in sport?

    Science.gov (United States)

    Papaloucas, Marios; Kyriazi, Kyriaki; Kouloulias, Vassilis

    2015-10-01

    Nowadays, antidoping laboratories are improving detection methods to confirm the use of forbidden substances. These tests are based both on direct identification of new substances or their metabolites and on indirect evaluation of changes in gene, protein, or metabolite patterns (genomics, proteomics, or metabolomics). The World Anti-Doping Agency (WADA) officially monitors anabolic steroids, hormones, growth factors, β-agonists, hormone and metabolic modulators, masking agents, street drugs, manipulation of blood and blood components, chemical and physical manipulation, gene doping, stimulants, narcotics, glucocorticosteroids, and β-blockers. However, several other substances are under review by WADA. Pheromones accomplish the structure and function of life from its first step, while they have an impact on the body's performance. Both testosterone and pheromones have an ergogenic effect that could potentially affect an athlete's performance. The authors share their questions concerning the potential impact of pheromones in sports.

  10. PHEROMONAL MODULATION OF REPRODUCTIVE FUNCTION IN MAMMALS

    Directory of Open Access Journals (Sweden)

    Matthieu Keller

    2011-11-01

    Full Text Available Social olfactory signals, often known as pheromones, are powerful regulators of reproductive function. These chemosignals can be detected by two olfactory systems, namely the main or the accessory olfactory systems. While initially anatomically segregated, both systems converge functionally as they can detect and process overlapping sets of chemosignals. This convergence also takes place at the level of their central projections in the hypothalamus. It is probably at this level that future investigations will be needed. Indeed, if the physiology of both olfactory system and reproductive function are now quite well characterized, the interrelation between both systems is unclear. Among the many cell populations that can serve as targets or relays for the pheromonal information in the hypothalamus are GnRH cells or the recently discovered Kispeptin population which have been showed to be activated after pheromonal activation. However, many works will be needed before having a definitive picture.

  11. Iodine volatility

    International Nuclear Information System (INIS)

    Beahm, E.C.; Shockley, W.E.

    1984-01-01

    The ultimate aim of this program is to couple experimental aqueous iodine volatilities to a fission product release model. Iodine partition coefficients, for inorganic iodine, have been measured during hydrolysis and radiolysis. The hydrolysis experiments have illustrated the importance of reaction time on iodine volatility. However, radiolysis effects can override hydrolysis in determining iodine volatility. In addition, silver metal in radiolysis samples can react to form silver iodide accompanied by a decrease in iodine volatility. Experimental data are now being coupled to an iodine transport and release model that was developed in the Federal Republic of Germany

  12. Identification of the sex pheromone of Lutzomyia longipalpis (Lutz & Neiva, 1912 (Diptera: Psychodidae from Asunción, Paraguay

    Directory of Open Access Journals (Sweden)

    Caballero Norath

    2009-11-01

    Full Text Available Abstract The sand fly Lutzomyia longipalpis is the main vector of Leishmania (L. infantum (Nicolle, the causative agent of American visceral leishmaniasis (AVL in the New World. Male Lu. longipalpis have secretory glands which produce sex pheromones in either abdominal tergites 4 or 3 and 4. These glands are sites of sex pheromone production and each pheromone type may represent true sibling species. In Latin America, apart from Lu. pseudolongipalpis Arrivillaga and Feliciangeli from Venezuela, populations of Lu. longipalpis s.l. can be identified by their male-produced sex pheromones: (S-9-methylgermacrene-B, 3-methyl-α-himachalene and the two cembrenes, 1 and 2. In this study, we present the results of a coupled gas chromatography - mass spectrometry analysis of the pheromones of males Lu. longipalpis captured in an endemic area of visceral leishmaniasis in Asunción, Paraguay. Our results show that Lu. longipalpis from this site produce (S-9-methylgermacrene-B which has also been found in Lu. longipalpis from different areas of Brazil, Colombia and Central America.

  13. Identification of the sex pheromone of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera: Psychodidae) from Asunción, Paraguay

    Science.gov (United States)

    Brazil, Reginaldo P; Caballero, Norath Natalia; Hamilton, James Gordon C

    2009-01-01

    The sand fly Lutzomyia longipalpis is the main vector of Leishmania (L.) infantum (Nicolle), the causative agent of American visceral leishmaniasis (AVL) in the New World. Male Lu. longipalpis have secretory glands which produce sex pheromones in either abdominal tergites 4 or 3 and 4. These glands are sites of sex pheromone production and each pheromone type may represent true sibling species. In Latin America, apart from Lu. pseudolongipalpis Arrivillaga and Feliciangeli from Venezuela, populations of Lu. longipalpis s.l. can be identified by their male-produced sex pheromones: (S)-9-methylgermacrene-B, 3-methyl-α-himachalene and the two cembrenes, 1 and 2. In this study, we present the results of a coupled gas chromatography - mass spectrometry analysis of the pheromones of males Lu. longipalpis captured in an endemic area of visceral leishmaniasis in Asunción, Paraguay. Our results show that Lu. longipalpis from this site produce (S)-9-methylgermacrene-B which has also been found in Lu. longipalpis from different areas of Brazil, Colombia and Central America. PMID:19883505

  14. Identification of the sex pheromone of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera: Psychodidae) from Asunción, Paraguay.

    Science.gov (United States)

    Brazil, Reginaldo P; Caballero, Norath Natalia; Hamilton, James Gordon C

    2009-11-02

    The sand fly Lutzomyia longipalpis is the main vector of Leishmania (L.) infantum (Nicolle), the causative agent of American visceral leishmaniasis (AVL) in the New World. Male Lu. longipalpis have secretory glands which produce sex pheromones in either abdominal tergites 4 or 3 and 4. These glands are sites of sex pheromone production and each pheromone type may represent true sibling species. In Latin America, apart from Lu. pseudolongipalpis Arrivillaga and Feliciangeli from Venezuela, populations of Lu. longipalpis s.l. can be identified by their male-produced sex pheromones: (S)-9-methylgermacrene-B, 3-methyl-alpha-himachalene and the two cembrenes, 1 and 2.In this study, we present the results of a coupled gas chromatography - mass spectrometry analysis of the pheromones of males Lu. longipalpis captured in an endemic area of visceral leishmaniasis in Asunción, Paraguay. Our results show that Lu. longipalpis from this site produce (S)-9-methylgermacrene-B which has also been found in Lu. longipalpis from different areas of Brazil, Colombia and Central America.

  15. Methodology in structural determination and synthesis of insect pheromone

    Directory of Open Access Journals (Sweden)

    Guo-Qiang Lin

    1991-01-01

    Full Text Available By means of ethereal washing of insect pheromone glands of female moths, GC-MS detection along with microchemical reactions and electroantennogram (EAG survey, six economically important insect species were targeted for pheromone identification. The discovery of a natural pheromone inhibitor, chemo-selectivity and species isolation by pheromone will be described. The modified triple bond migration and triethylamine liganded vinyl cuprate were applied for achiral pheromone synthesis in double bond formation. Some optically active pheromones and their stereoisomers were synthesized through chiral pool or asymmetric synthesis. Some examples of chiral recognition of insects towards their chiral pheromones will be discussed. A CaH2 and silica gel catalyzed Sharpless Expoxidation Reaction was found in shortening the reaction time.

  16. Sex in the night: fatty acid-derived sex pheromones and corresponding membrane pheromone receptors in insects.

    Science.gov (United States)

    Koutroumpa, Fotini A; Jacquin-Joly, Emmanuelle

    2014-12-01

    The moth sex pheromone communication is one of the most striking examples of chemical communication in the animal kingdom. Investigating the molecular mechanisms of pheromone biosynthesis in the female pheromone gland and of pheromone reception in the male antennae not only defines new concepts in signalling research but also opens new perspectives for insect control. In this mini-review, we use the cotton leafworm Spodoptera littoralis as a guideline to illustrate the recent advances gained in the understanding of moth sex pheromone communication. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  17. Pheromone binding proteins enhance the sensitivity of olfactory receptors to sex pheromones in Chilo suppressalis.

    Science.gov (United States)

    Chang, Hetan; Liu, Yang; Yang, Ting; Pelosi, Paolo; Dong, Shuanglin; Wang, Guirong

    2015-08-27

    Sexual communication in moths offers a simplified scenario to model and investigate insect sensory perception. Both PBPs (pheromone-binding proteins) and PRs (pheromone receptors) are involved in the detection of sex pheromones, but the interplay between them still remains largely unknown. In this study, we have measured the binding affinities of the four recombinant PBPs of Chilo suppressalis (CsupPBPs) to pheromone components and analogs and characterized the six PRs using the Xenopus oocytes expression system. Interestingly, when the responses of PRs were recorded in the presence of PBPs, we measured in several combinations a dramatic increase in signals as well as in sensitivity of such combined systems. Furthermore, the discrimination ability of appropriate combinations of PRs and PBPs was improved compared with the performance of PBPs or PRs alone. Besides further supporting a role of PBPs in the pheromone detection and discrimination, our data shows for the first time that appropriate combinations of PRs and PBPs improved the discrimination ability of PBPs or PRs alone. The variety of responses measured with different pairing of PBPs and PRs indicates the complexity of the olfaction system, which, even for the relatively simple task of detecting sex pheromones, utilises a highly sophisticated combinatorial approach.

  18. A new class of mealybug pheromones: a hemiterpene ester in the sex pheromone of Crisicoccus matsumotoi

    Science.gov (United States)

    Tabata, Jun; Narai, Yutaka; Sawamura, Nobuo; Hiradate, Syuntaro; Sugie, Hajime

    2012-07-01

    Mealybugs, which include several agricultural pests, are small sap feeders covered with a powdery wax. They exhibit clear sexual dimorphism; males are winged but fragile and short lived, whereas females are windless and less mobile. Thus, sex pheromones emitted by females facilitate copulation and reproduction by serving as a key navigation tool for males. Although the structures of the hitherto known mealybug pheromones vary among species, they have a common structural motif; they are carboxylic esters of monoterpene alcohols with irregular non-head-to-tail linkages. However, in the present study, we isolated from the Matsumoto mealybug, Crisicoccus matsumotoi (Siraiwa), a pheromone with a completely different structure. Using gas chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy, we identified the pheromone as 3-methyl-3-butenyl 5-methylhexanoate. Its attractiveness to males was confirmed in a series of field trapping experiments involving comparison between the isolated natural product and a synthetic sample. This is the first report of a hemiterpene mealybug pheromone. In addition, the acid moiety (5-methylhexanoate) appears to be rare in insect pheromones.

  19. Changes in pheromone production, release, mating behaviour and reproductive ability of the gamma-irradiated cockroach Nauphoeta cinerea (Olivier)

    International Nuclear Information System (INIS)

    Menon, M.

    1978-01-01

    Mature males of Nauphoeta cinerea produce a sex pheromone 'seducin' which has short-range effects in attracting mature females of the same species. Exposure of newly-emerged adult males to 3.5, 7, 14 or 21 krad of gamma-radiation decreased their life expectancy and affected their mating behaviour. Bioassay of dichloromethane extracts of males showed that radiation doses (14 krad) sufficient to induce sterility did not affect the ability to produce pheromone but significantly reduced the release of pheromone by inhibiting wing-raising. The sterile-male technique using males sterilized by ionizing radiation in air may not be the method of choice for control of Nauphoeta cinerea. (author)

  20. Enterococcus faecalis Sex Pheromone cCF10 Enhances Conjugative Plasmid Transfer In Vivo

    Directory of Open Access Journals (Sweden)

    Helmut Hirt

    2018-02-01

    Full Text Available Cell-cell communication mediated by peptide pheromones (cCF10 [CF] is essential for high-frequency plasmid transfer in vitro in Enterococcus faecalis. To examine the role of pheromone signaling in vivo, we established either a CF-producing (CF+ recipient or a recipient producing a biologically inactive variant of CF (CF− recipient in a germfree mouse model 3 days before donor inoculation and determined transfer frequencies of the pheromone-inducible plasmid pCF10. Plasmid transfer was detected in the upper and middle sections of the intestinal tract 5 h after donor inoculation and was highly efficient in the absence of antibiotic selection. The transconjugant/donor ratio reached a maximum level approaching 1 on day 4 in the upper intestinal tract. Plasmid transfer was significantly lower with the CF− recipient. While rescue of the CF− mating defect by coculture with CF+ recipients is easily accomplished in vitro, no extracellular complementation occurred in vivo. This suggests that most pheromone signaling in the gut occurs between recipient and donor cells in very close proximity. Plasmid-bearing cells (donors plus transconjugants steadily increased in the population from 0.1% after donor inoculation to about 10% at the conclusion of the experiments. This suggests a selective advantage of pCF10 carriage distinct from antibiotic resistance or bacteriocin production. Our results demonstrate that pheromone signaling is required for efficient pCF10 transfer in vivo. In the absence of CF+ recipients, a low level of transfer to CF− recipients occurred in the gut. This may result from low-level host-mediated induction of the donors in the gastrointestinal (GI tract, similar to that previously observed in serum.

  1. Host-Tree Monoterpenes and Biosynthesis of Aggregation Pheromones in the Bark Beetle Ips paraconfusus

    Directory of Open Access Journals (Sweden)

    John A. Byers

    2012-01-01

    Full Text Available A paradigm developed in the 1970s that Ips bark beetles biosynthesize their aggregation pheromone components ipsenol and ipsdienol by hydroxylating myrcene, a host tree monoterpene. Similarly, host α-pinene was hydroxylated to a third pheromone component cis-verbenol. In 1990, however, we reported that amounts of ipsenol and ipsdienol produced by male Ips paraconfusus (Coleoptera: Scolytinae feeding in five host pine species were nearly the same, even though no detectable myrcene precursor was detected in one of these pines (Pinus sabiniana. Subsequent research showed ipsenol and ipsdienol are also biosynthesized from smaller precursors such as acetate and mevalonate, and this de novo pathway is the major one, while host tree myrcene conversion by the beetle is the minor one. We report concentrations of myrcene, α-pinene and other major monoterpenes in five pine hosts (Pinus ponderosa, P. lambertiana, P. jeffreyi, P. sabiniana, and P. contorta of I. paraconfusus. A scheme for biosynthesis of ipsdienol and ipsenol from myrcene and possible metabolites such as ipsenone is presented. Mass spectra and quantities of ipsenone are reported and its possible role in biosynthesis of aggregation pheromone. Coevolution of bark beetles and host trees is discussed in relation to pheromone biosynthesis, host plant selection/suitability, and plant resistance.

  2. Quantitative Trait Locus Analysis of Mating Behavior and Male Sex Pheromones in Nasonia Wasps

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    Wenwen Diao

    2016-06-01

    Full Text Available A major focus in speciation genetics is to identify the chromosomal regions and genes that reduce hybridization and gene flow. We investigated the genetic architecture of mating behavior in the parasitoid wasp species pair Nasonia giraulti and Nasonia oneida that exhibit strong prezygotic isolation. Behavioral analysis showed that N. oneida females had consistently higher latency times, and broke off the mating sequence more often in the mounting stage when confronted with N. giraulti males compared with males of their own species. N. oneida males produce a lower quantity of the long-range male sex pheromone (4R,5S-5-hydroxy-4-decanolide (RS-HDL. Crosses between the two species yielded hybrid males with various pheromone quantities, and these males were used in mating trials with females of either species to measure female mate discrimination rates. A quantitative trait locus (QTL analysis involving 475 recombinant hybrid males (F2, 2148 reciprocally backcrossed females (F3, and a linkage map of 52 equally spaced neutral single nucleotide polymorphism (SNP markers plus SNPs in 40 candidate mating behavior genes revealed four QTL for male pheromone amount, depending on partner species. Our results demonstrate that the RS-HDL pheromone plays a role in the mating system of N. giraulti and N. oneida, but also that additional communication cues are involved in mate choice. No QTL were found for female mate discrimination, which points at a polygenic architecture of female choice with strong environmental influences.

  3. Aggregation pheromones for monitoring the coconut rhinoceros beetle (Oryctes rhinoceros) in Jerukwangi Village, Jepara, Indonesia

    Science.gov (United States)

    Indriyanti, D. R.; Lutfiana, J. E.; Widiyaningrum, P.; Susilowati, E.; Slamet, M.

    2018-03-01

    Oryctes rhinoceros (Coleoptera: Scarabaeidae) is the most serious pest of coconut plantations in Indonesia. Jerukwangi Village is O. rhinoceros attacked one of the coconuts producing villages with more than 75% of the coconut plant population O. rhinoceros. The study aimed to monitor the population and analyze the sex ratio of O. rhinoceros that were attracted to aggregation pheromones in the field. Aggregation pheromones is a chemical compound containing Ethyl 4-methyl octanoate. The pheromone compounds were placed in traps (buckets), hung 2 meters above the ground. The traps were observed, and the beetles trapped were counted every week. In 12 weeks of monitoring, the traps captured 101 insects consist of 90.1% O. rhinoceros and 9.9% other insect species (Rhynchophorus ferrugineus and Xylotrupes gideon). This result indicates the high population of O. rhinoceros in the field. Aggregation pheromone is useful for attracting females. Rhinoceros by 61% and the males by 39%. The advantage of research is it can be used in integrated pest management (IPM) packages for monitoring of beetle population, and removal of beetles.

  4. Pheromonal Cues Deposited by Mated Females Convey Social Information about Egg-Laying Sites in Drosophila Melanogaster.

    Science.gov (United States)

    Duménil, Claire; Woud, David; Pinto, Francesco; Alkema, Jeroen T; Jansen, Ilse; Van Der Geest, Anne M; Roessingh, Sanne; Billeter, Jean-Christophe

    2016-03-01

    Individuals can make choices based on information learned from others, a phenomenon called social learning. How observers differentiate between which individual they should or should not learn from is, however, poorly understood. Here, we showed that Drosophila melanogaster females can influence the choice of egg-laying site of other females through pheromonal marking. Mated females mark territories of high quality food by ejecting surplus male sperm containing the aggregation pheromone cis-11-vaccenyl acetate (cVA) and, in addition, deposit several sex- and species-specific cuticular hydrocarbon (CHC) pheromones. These pheromonal cues affect the choices of other females, which respond by preferentially laying eggs on the marked food. This system benefits both senders and responders, as communal egg laying increases offspring survival. Virgin females, however, do not elicit a change in the egg-laying decision of mated females, even when food has been supplemented with ejected sperm from mated females, thus indicating the necessity for additional cues. Genetic ablation of either a female's CHC pheromones or those of their mate results in loss of ability of mated females to attract other females. We conclude that mated females use a pheromonal marking system, comprising cVA acquired from male ejaculate with sex- and species-specific CHCs produced by both mates, to indicate egg-laying sites. This system ensures information reliability because mated, but not virgin, females have both the ability to generate the pheromone blend that attracts other flies to those sites and a direct interest in egg-laying site quality.

  5. A moth pheromone brewery: production of (Z)-11-hexadecenol by heterologous co-expression of two biosynthetic genes from a noctuid moth in a yeast cell factory.

    Science.gov (United States)

    Hagström, Åsa K; Wang, Hong-Lei; Liénard, Marjorie A; Lassance, Jean-Marc; Johansson, Tomas; Löfstedt, Christer

    2013-12-13

    Moths (Lepidoptera) are highly dependent on chemical communication to find a mate. Compared to conventional unselective insecticides, synthetic pheromones have successfully served to lure male moths as a specific and environmentally friendly way to control important pest species. However, the chemical synthesis and purification of the sex pheromone components in large amounts is a difficult and costly task. The repertoire of enzymes involved in moth pheromone biosynthesis in insecta can be seen as a library of specific catalysts that can be used to facilitate the synthesis of a particular chemical component. In this study, we present a novel approach to effectively aid in the preparation of semi-synthetic pheromone components using an engineered vector co-expressing two key biosynthetic enzymes in a simple yeast cell factory. We first identified and functionally characterized a ∆11 Fatty-Acyl Desaturase and a Fatty-Acyl Reductase from the Turnip moth, Agrotis segetum. The ∆11-desaturase produced predominantly Z11-16:acyl, a common pheromone component precursor, from the abundant yeast palmitic acid and the FAR transformed a series of saturated and unsaturated fatty acids into their corresponding alcohols which may serve as pheromone components in many moth species. Secondly, when we co-expressed the genes in the Brewer's yeast Saccharomyces cerevisiae, a set of long-chain fatty acids and alcohols that are not naturally occurring in yeast were produced from inherent yeast fatty acids, and the presence of (Z)-11-hexadecenol (Z11-16:OH), demonstrated that both heterologous enzymes were active in concert. A 100 ml batch yeast culture produced on average 19.5 μg Z11-16:OH. Finally, we demonstrated that oxidized extracts from the yeast cells containing (Z)-11-hexadecenal and other aldehyde pheromone compounds elicited specific electrophysiological activity from male antennae of the Tobacco budworm, Heliothis virescens, supporting the idea that genes from different

  6. Alarm pheromone processing in the ant brain: an evolutionary perspective

    Directory of Open Access Journals (Sweden)

    Makoto Mizunami

    2010-06-01

    Full Text Available Social insects exhibit sophisticated communication by means of pheromones, one example of which is the use of alarm pheromones to alert nestmates for colony defense. We review recent advances in the understanding of the processing of alarm pheromone information in the ant brain. We found that information about formic acid and n-undecane, alarm pheromone components, is processed in a set of specific glomeruli in the antennal lobe of the ant Camponotus obscuripes. Alarm pheromone information is then transmitted, via projection neurons, to the lateral horn and the calyces of the mushroom body of the protocerebrum. In the lateral horn, we found a specific area where terminal boutons of alarm pheromone-sensitive projection neurons are more densely distributed than in the rest of the lateral horn. Some neurons in the protocerebrum responded specifically to formic acid or n-undecane and they may participate in the control of behavioral responses to each pheromone component. Other neurons, especially those originating from the mushroom body lobe, responded also to non-pheromonal odors and may play roles in integration of pheromonal and non-pheromonal signals. We found that a class of neurons receive inputs in the lateral horn and the mushroom body lobe and terminate in a variety of premotor areas. These neurons may participate in the control of aggressive behavior, which is sensitized by alarm pheromones and is triggered by non-pheromonal sensory stimuli associated with a potential enemy. We propose that the alarm pheromone processing system has evolved by differentiation of a part of general odor processing system.

  7. Differentiation of Commercial PDO Wines Produced in Istria (Croatia According to Variety and Harvest Year Based on HS-SPME-GC/MS Volatile Aroma Compound Profiling

    Directory of Open Access Journals (Sweden)

    Igor Lukić

    2017-01-01

    Full Text Available To differentiate monovarietal wines made from native and introduced varieties in Istria (Croatia, samples of Malvazija istarska, Chardonnay and Muscat yellow from two harvest years (2013 and 2014 were subjected to headspace solid-phase microextraction and gas chromatographic/mass spectrometric analysis (HS-SPME-GC/MS of volatile aroma compounds. Significant effects of variety and harvest year were determined, but their interaction complicated the differentiation. Particular compounds were consistent as markers of variety in both years: nerol for Malvazija, ethyl cinnamate and a tentatively identified isomer of dimethylbenzaldehyde for Chardonnay, and terpenes for Muscat yellow. Wines from 2013 contained higher concentrations of the majority of important volatiles. A 100 % correct differentiation of Malvazija istarska and Chardonnay wines according to both variety and harvest year was achieved by stepwise linear discriminant analysis.

  8. Differentiation of Commercial PDO Wines Produced in Istria (Croatia) According to Variety and Harvest Year Based on HS-SPME-GC/MS Volatile Aroma Compound Profiling.

    Science.gov (United States)

    Lukić, Igor; Horvat, Ivana

    2017-03-01

    To differentiate monovarietal wines made from native and introduced varieties in Istria (Croatia), samples of Malvazija istarska, Chardonnay and Muscat yellow from two harvest years (2013 and 2014) were subjected to headspace solid-phase microextraction and gas chromatographic/mass spectrometric analysis (HS-SPME-GC/MS) of volatile aroma compounds. Significant effects of variety and harvest year were determined, but their interaction complicated the differentiation. Particular compounds were consistent as markers of variety in both years: nerol for Malvazija, ethyl cinnamate and a tentatively identified isomer of dimethylbenzaldehyde for Chardonnay, and terpenes for Muscat yellow. Wines from 2013 contained higher concentrations of the majority of important volatiles. A 100% correct differentiation of Malvazija istarska and Chardonnay wines according to both variety and harvest year was achieved by stepwise linear discriminant analysis.

  9. Unstable volatility

    DEFF Research Database (Denmark)

    Casas, Isabel; Gijbels, Irène

    2012-01-01

    The objective of this paper is to introduce the break-preserving local linear (BPLL) estimator for the estimation of unstable volatility functions for independent and asymptotically independent processes. Breaks in the structure of the conditional mean and/or the volatility functions are common...... in Finance. Nonparametric estimators are well suited for these events due to the flexibility of their functional form and their good asymptotic properties. However, the local polynomial kernel estimators are not consistent at points where the volatility function has a break. The estimator presented...

  10. Site of pheromone biosynthesis and isolation of HMG-CoA reductase cDNA in the cotton boll weevil, Anthonomus grandis.

    Science.gov (United States)

    Taban, A Huma; Fu, Jessica; Blake, Jacob; Awano, Ami; Tittiger, Claus; Blomquist, Gary J

    2006-08-01

    Isolated gut tissue from male cotton boll weevil, Anthonomus grandis (Coleoptera: Curculionidae), incorporated radiolabeled acetate into components that co-eluted with monoterpenoid pheromone components on HPLC. This demonstrates that pheromone components of male A. grandis are produced de novo and strongly suggests that pheromone biosynthesis occurs in gut tissue. A central enzyme in isoprenoid biosynthesis is 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-R), and a full-length HMG-R cDNA was isolated from A. grandis. The predicted translation product was 54 and 45% identical to HMG-R from Ips paraconfusus and Drosophila melanogaster, respectively. HMG-R gene expression gradually increased with age in male A. grandis, which correlates with pheromone production. However, topical application of JH III did not significantly increase HMG-R mRNA levels.

  11. Chasing volatility

    DEFF Research Database (Denmark)

    Caporin, Massimiliano; Rossi, Eduardo; Santucci de Magistris, Paolo

    The realized volatility of financial returns is characterized by persistence and occurrence of unpreditable large increments. To capture those features, we introduce the Multiplicative Error Model with jumps (MEM-J). When a jump component is included in the multiplicative specification, the condi......The realized volatility of financial returns is characterized by persistence and occurrence of unpreditable large increments. To capture those features, we introduce the Multiplicative Error Model with jumps (MEM-J). When a jump component is included in the multiplicative specification...... estimate alternative specifications of the model using a set of daily bipower measures for 7 stock indexes and 16 individual NYSE stocks. The estimates of the jump component confirm that the probability of jumps dramatically increases during the financial crisis. Compared to other realized volatility...... models, the introduction of the jump component provides a sensible improvement in the fit, as well as for in-sample and out-of-sample volatility tail forecasts....

  12. Sex pheromone component ratios and mating isolation among three Lygus plant bug species of North America

    Science.gov (United States)

    Byers, John A.; Fefer, Daniela; Levi-Zada, Anat

    2013-12-01

    The plant bugs Lygus hesperus, Lygus lineolaris, and Lygus elisus (Hemiptera: Miridae) are major pests of many agricultural crops in North America. Previous studies suggested that females release a sex pheromone attractive to males. Other studies showed that males and females contain microgram amounts of ( E)-4-oxo-2-hexenal, hexyl butyrate, and ( E)-2-hexenyl butyrate that are emitted as a defense against predators. Using gas chromatography-mass spectrometry, we found that female L. lineolaris and L. elisus have a 4:10 ratio of hexyl butyrate to ( E)-2-hexenyl butyrate that is reversed from the 10:1 ratio in female L. hesperus (males of the three species have ~10:1 ratio). These reversed ratios among females of the species suggest a behavioral role. Because both sexes have nearly equal amounts of the major volatiles, females should release more to attract males. This expectation was supported because L. hesperus females released more hexyl butyrate (mean of 86 ng/h) during the night (1800-0700 hours) than did males (pheromone component for all three species, ( E)-2-hexenyl butyrate is essential for L. elisus and L. lineolaris, and hexyl butyrate is essential for L. hesperus. However, all three components are recognized by each species since ratios of the butyrate esters are critical for conspecific attraction and heterospecific avoidance by males and thus play a role in reproductive isolation among the three species. Because L. hesperus males and females are known to emit these major volatiles for repelling ant predators, our study links defensive allomones in Lygus bugs with an additional use as sex pheromones.

  13. From sexual attraction to maternal aggression: when pheromones change their behavioural significance.

    Science.gov (United States)

    Martín-Sánchez, Ana; McLean, Lynn; Beynon, Robert J; Hurst, Jane L; Ayala, Guillermo; Lanuza, Enrique; Martínez-Garcia, Fernando

    2015-02-01

    This article is part of a Special Issue "Chemosignals and Reproduction". This paper reviews the role of chemosignals in the socio-sexual interactions of female mice, and reports two experiments testing the role of pup-derived chemosignals and the male sexual pheromone darcin in inducing and promoting maternal aggression. Female mice are attracted to urine-borne male pheromones. Volatile and non-volatile urine fractions have been proposed to contain olfactory and vomeronasal pheromones. In particular, the male-specific major urinary protein (MUP) MUP20, darcin, has been shown to be rewarding and attractive to females. Non-urinary male chemosignals, such as the lacrimal protein ESP1, promote lordosis in female mice, but its attractive properties are still to be tested. There is evidence indicating that ESP1 and MUPs are detected by vomeronasal type 2 receptors (V2R). When a female mouse becomes pregnant, she undergoes dramatic changes in her physiology and behaviour. She builds a nest for her pups and takes care of them. Dams also defend the nest against conspecific intruders, attacking especially gonadally intact males. Maternal behaviour is dependent on a functional olfactory system, thus suggesting a role of chemosignals in the development of maternal behaviour. Our first experiment demonstrates, however, that pup chemosignals are not sufficient to induce maternal aggression in virgin females. In addition, it is known that vomeronasal stimuli are needed for maternal aggression. Since MUPs (and other molecules) are able to promote intermale aggression, in our second experiment we test if the attractive MUP darcin also promotes attacks on castrated male intruders by lactating dams. Our findings demonstrate that the same chemosignal, darcin, promotes attraction or aggression according to female reproductive state. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Pheromone reception in moths: from molecules to behaviors.

    Science.gov (United States)

    Zhang, Jin; Walker, William B; Wang, Guirong

    2015-01-01

    Male moths detect and find their mates using species-specific sex pheromones emitted by conspecific females. Olfaction plays a vital role in this behavior. Since the first discovery of an insect sex pheromone from the silkmoth Bombyx mori, great efforts have been spent on understanding the sensing of the pheromones in vivo. Much progress has been made in elucidating the molecular mechanisms that mediate chemoreception in insects in the past few decades. In this review, we focus on pheromone reception and detection in moths, from the molecular to the behavioral level. We trace the information pathway from the capture of pheromone by male antennae, binding and transportation to olfactory receptor neurons, receptor activation, signal transduction, molecule inactivation, through brain processing and behavioral response. We highlight the impact of recent studies and also provide our insights into pheromone processing. © 2015 Elsevier Inc. All rights reserved.

  15. Carbon monoxide production from five volatile anesthetics in dry sodalime in a patient model: halothane and sevoflurane do produce carbon monoxide; temperature is a poor predictor of carbon monoxide production

    Directory of Open Access Journals (Sweden)

    Perez Roberto SGM

    2005-06-01

    Full Text Available Abstract Background Desflurane and enflurane have been reported to produce substantial amounts of carbon monoxide (CO in desiccated sodalime. Isoflurane is said to produce less CO and sevoflurane and halothane should produce no CO at all. The purpose of this study is to measure the maximum amounts of CO production for all modern volatile anesthetics, with completely dry sodalime. We also tried to establish a relationship between CO production and temperature increase inside the sodalime. Methods A patient model was simulated using a circle anesthesia system connected to an artificial lung. Completely desiccated sodalime (950 grams was used in this system. A low flow anesthesia (500 ml/min was maintained using nitrous oxide with desflurane, enflurane, isoflurane, halothane or sevoflurane. For immediate quantification of CO production a portable gas chromatograph was used. Temperature was measured within the sodalime container. Results Peak concentrations of CO were very high with desflurane and enflurane (14262 and 10654 ppm respectively. It was lower with isoflurane (2512 ppm. We also measured small concentrations of CO for sevoflurane and halothane. No significant temperature increases were detected with high CO productions. Conclusion All modern volatile anesthetics produce CO in desiccated sodalime. Sodalime temperature increase is a poor predictor of CO production.

  16. Propheromones that release pheromonal carbonyl compounds in light.

    Science.gov (United States)

    Liu, X; Macaulay, E D; Pickett, J A

    1984-05-01

    Pheromonal carbonyl compounds; (Z)-11-hexadecanal, (E)-citral, and 2-heptanone were treated with six alcohols to give acetals or ketals, some of which acted as propheromones by releasing the pheromonal carbonyl compounds in ultraviolet or simulated sunlight. Highest yields of pheromone were obtained from adducts prepared witho-nitrobenzyl alcohol ando-nitrophenylethane-1,2-diol. Adducts from (Z)-11-hexadecenal and these two alcohols were employed in lures to catch diamondback moths,Plutella xylostella (L.).

  17. Molecular switches for pheromone release from a moth pheromone-binding protein

    International Nuclear Information System (INIS)

    Xu Wei; Leal, Walter S.

    2008-01-01

    Pheromone-binding proteins (PBPs) are involved in the uptake of pheromones from pores on the antennae, transport through an aqueous environment surrounding the olfactory receptor neurons, and fast delivery to pheromone receptors. We tested the hypothesis that a C-terminal segment and a flexible loop are involved in the release of pheromones to membrane-bound receptors. We expressed in Escherichia coli 11 mutants of the PBP from the silkworm moth, BmorPBP, taking into consideration structural differences between the forms with high and low binding affinity. The N-terminus was truncated and His-69, His-70 and His-95 at the base of a flexible loop, and a cluster of acidic residues at the C-terminus were mutated. Binding assays and circular dichroism analyses support a mechanism involving protonation of acidic residues Asp-132 and Glu-141 at the C-terminus and histidines, His-70 and His-95, in the base of a loop covering the binding pocket. The former leads to the formation of a new α-helix, which competes with pheromone for the binding pocket, whereas positive charge repulsion of the histidines opens the opposite side of the binding pocket

  18. Identification of pheromone-carrying protein in the preorbital gland post in the endangered Indian male Blackbuck Antelope cervicapra L.

    Science.gov (United States)

    Rajagopal, T; Rajkumar, R; Ponmanickam, P; Achiraman, S; Padmanabhan, P; Archunan, G

    2015-12-01

    In mammals, a low molecular mass protein (17-20 KDa) reported from the pheromone sources such as urine, saliva, glandular secretion, etc., as ligand-carrier (pheromone carrier) has been associated with chemo-communication. Since the preorbital gland post is one of the major pheromone sources in Indian Blackbuck, an endangered species, we assumed that it possibly contains low molecular mass protein for chemical communication. Hence, we investigated the preorbital gland post in territorial and non-territorial male blackbucks for such low molecular mass proteins adopting SDS-PAGE and LC-MS/MS analysis. The total content of protein was higher in the post of territorial males than non-territorial males of adult and sub-adult. In fact, the protein profiles such as 17, 21, 25, 42 and 61 kDa were noted in the gland secretion of territorial and non-territorial males. The intensity of the 17 kDa protein band was higher in territorial males than non-territorial males. In-gel trypsin digestion of the 17 kDa band was processed and subjected to LC-MS/MS and SEQUEST analyses. The results of LC-MS/MS and SEQUEST search showed the presence of α(2u)-globulin in the 17 kDa band. In addition, the identified α(2u)-globulin sequence possessed GDW residues, which are the characteristic signature for lipocalin family. Since the α(2u)-globulin has been reported from the pheromone-carrying proteins in some mammals, this protein may carry the volatiles (pheromone compounds) in male Blackbucks preorbital gland to evoke the scent marking for maintaining territoriality (home range) and attraction towards female, through the secretion of glandular protein.

  19. Sex pheromone biosynthetic pathways are conserved between moths and the butterfly Bicyclus anynana

    Science.gov (United States)

    Liénard, Marjorie A; Wang, Hong-Lei; Lassance, Jean-Marc; Löfstedt, Christer

    2014-01-01

    Although phylogenetically nested within the moths, butterflies have diverged extensively in a number of life history traits. Whereas moths rely greatly on chemical signals, visual advertisement is the hallmark of mate finding in butterflies. In the context of courtship, however, male chemical signals are widespread in both groups although they likely have multiple evolutionary origins. Here, we report that in males of the butterfly Bicyclus anynana, courtship scents are produced de novo via biosynthetic pathways shared with females of many moth species. We show that two of the pheromone components that play a major role in mate choice, namely the (Z)-9-tetradecenol and hexadecanal, are produced through the activity of a fatty acyl Δ11-desaturase and two specialized alcohol-forming fatty acyl reductases. Our study provides the first evidence of conservation and sharing of ancestral genetic modules for the production of FA-derived pheromones over a long evolutionary timeframe thereby reconciling mate communication in moths and butterflies. PMID:24862548

  20. A yeast pheromone-based inter-species communication system.

    Science.gov (United States)

    Hennig, Stefan; Clemens, André; Rödel, Gerhard; Ostermann, Kai

    2015-02-01

    We report on a pheromone-based inter-species communication system, allowing for a controlled cell-cell communication between the two species Saccharomyces cerevisiae and Schizosaccharomyces pombe as a proof of principle. It exploits the mating response pathways of the two yeast species employing the pheromones, α- or P-factor, as signaling molecules. The authentic and chimeric pheromone-encoding genes were engineered to code for the P-factor in S. cerevisiae and the α-factor in S. pombe. Upon transformation of the respective constructs, cells were enabled to express the mating pheromone of the opposite species. The supernatant of cultures of S. pombe cells expressing α-factor were able to induce a G1 arrest in the cell cycle, a change in morphology to the typical shmoo effect and expression driven by the pheromone-responsive FIG1 promoter in S. cerevisiae. The supernatant of cultures of S. cerevisiae cells expressing P-factor similarly induced cell cycle arrest in G1, an alteration in morphology typical for mating as well as the activation of the pheromone-responsive promoters of the rep1 and sxa2 genes in a pheromone-hypersensitive reporter strain of S. pombe. Apparently, both heterologous pheromones were correctly processed and secreted in an active form by the cells of the other species. Our data clearly show that the species-specific pheromone systems of yeast species can be exploited for a controlled inter-species communication.

  1. Olfaction and Pheromones: Uncanonical Sensory Influences and Bulbar Interactions

    Directory of Open Access Journals (Sweden)

    Víctor Vargas-Barroso

    2017-11-01

    Full Text Available The rodent main and accessory olfactory systems (AOS are considered functionally and anatomically segregated information-processing pathways. Each system is devoted to the detection of volatile odorants and pheromones, respectively. However, a growing number of evidences supports a cooperative interaction between them. For instance, at least four non-canonical receptor families (i.e., different from olfactory and vomeronasal receptor families have been recently discovered. These atypical receptor families are expressed in the sensory organs of the nasal cavity and furnish parallel processing-pathways that detect specific stimuli and mediate specific behaviors as well. Aside from the receptor and functional diversity of these sensory modalities, they converge into a poorly understood bulbar area at the intersection of the main- main olfactory bulb (MOB and accessory olfactory bulb (AOB that has been termed olfactory limbus (OL. Given the intimate association the OL with specialized glomeruli (i.e., necklace and modified glomeruli receiving uncanonical sensory afferences and its interactions with the MOB and AOB, the possibility that OL is a site of non-olfactory and atypical vomeronasal sensory decoding is discussed.

  2. Volatility in energy prices

    International Nuclear Information System (INIS)

    Duffie, D.

    1999-01-01

    This chapter with 58 references reviews the modelling and empirical behaviour of volatility in energy prices. Constant volatility and stochastic volatility are discussed. Markovian models of stochastic volatility are described and the different classes of Markovian stochastic volatility model are examined including auto-regressive volatility, option implied and forecasted volatility, Garch volatility, Egarch volatility, multivariate Garch volatility, and stochastic volatility and dynamic hedging policies. Other volatility models and option hedging are considered. The performance of several stochastic volatility models as applied to heating oil, light oil, natural gas, electricity and light crude oil are compared

  3. Identification of the pheromone biosynthesis genes from the sex pheromone gland transcriptome of the diamondback moth, Plutella xylostella

    OpenAIRE

    Chen, Da-Song; Dai, Jian-Qing; Han, Shi-Chou

    2017-01-01

    The diamondback moth was estimated to increase costs to the global agricultural economy as the global area increase of Brassica vegetable crops and oilseed rape. Sex pheromones traps are outstanding tools available in Integrated Pest Management for many years and provides an effective approach for DBM population monitoring and control. The ratio of two major sex pheromone compounds shows geographical variations. However, the limitation of our information in the DBM pheromone biosynthesis damp...

  4. Structural and functional analysis of Aplysia attractins, a family of water-borne protein pheromones with interspecific attractiveness

    NARCIS (Netherlands)

    Painter, S.D.; Cummins, S.F.; Nichols, A.E.; Akalal, D.B.G.; Schein, C.H.; Braun, W.; Smith, J.S.; Susswein, A.J.; Levy, M.; de Boer, P.A.C.M.; ter Maat, A.; Miller, M.W.; Scanlan, C.; Milberg, R.M.; Sweedler, J.V.; Nagle, G.T.

    2004-01-01

    Mate attraction in Aplysia involves a long-distance water-borne signal (the protein pheromone attractin), which is released during egg laying. Aplysia californica attractin attracts species that produce closely related attractins, such as Aplysia brasiliana, whose geographic distribution does not

  5. Novel sex cells and evidence for sex pheromones in diatoms.

    Science.gov (United States)

    Sato, Shinya; Beakes, Gordon; Idei, Masahiko; Nagumo, Tamotsu; Mann, David G

    2011-01-01

    Diatoms belong to the stramenopiles, one of the largest groups of eukaryotes, which are primarily characterized by a presence of an anterior flagellum with tubular mastigonemes and usually a second, smooth flagellum. Based on cell wall morphology, diatoms have historically been divided into centrics and pennates, of which only the former have flagella and only on the sperm. Molecular phylogenies show the pennates to have evolved from among the centrics. However, the timing of flagellum loss--whether before the evolution of the pennate lineage or after--is unknown, because sexual reproduction has been so little studied in the 'araphid' basal pennate lineages, to which Pseudostaurosira belongs. Sexual reproduction of an araphid pennate, Pseudostaurosira trainorii, was studied with light microscopy (including time lapse observations and immunofluorescence staining observed under confocal scanning laser microscopy) and SEM. We show that the species produces motile male gametes. Motility is mostly associated with the extrusion and retrieval of microtubule-based 'threads', which are structures hitherto unknown in stramenopiles, their number varying from one to three per cell. We also report experimental evidence for sex pheromones that reciprocally stimulate sexualization of compatible clones and orientate motility of the male gametes after an initial 'random walk'. The threads superficially resemble flagella, in that both are produced by male gametes and contain microtubules. However, one striking difference is that threads cannot beat or undulate and have no motility of their own, and they do not bear mastigonemes. Threads are sticky and catch and draw objects, including eggs. The motility conferred by the threads is probably crucial for sexual reproduction of P. trainorii, because this diatom is non-motile in its vegetative stage but obligately outbreeding. Our pheromone experiments are the first studies in which gametogenesis has been induced in diatoms by cell

  6. Novel sex cells and evidence for sex pheromones in diatoms.

    Directory of Open Access Journals (Sweden)

    Shinya Sato

    Full Text Available BACKGROUND: Diatoms belong to the stramenopiles, one of the largest groups of eukaryotes, which are primarily characterized by a presence of an anterior flagellum with tubular mastigonemes and usually a second, smooth flagellum. Based on cell wall morphology, diatoms have historically been divided into centrics and pennates, of which only the former have flagella and only on the sperm. Molecular phylogenies show the pennates to have evolved from among the centrics. However, the timing of flagellum loss--whether before the evolution of the pennate lineage or after--is unknown, because sexual reproduction has been so little studied in the 'araphid' basal pennate lineages, to which Pseudostaurosira belongs. METHODS/PRINCIPAL FINDING: Sexual reproduction of an araphid pennate, Pseudostaurosira trainorii, was studied with light microscopy (including time lapse observations and immunofluorescence staining observed under confocal scanning laser microscopy and SEM. We show that the species produces motile male gametes. Motility is mostly associated with the extrusion and retrieval of microtubule-based 'threads', which are structures hitherto unknown in stramenopiles, their number varying from one to three per cell. We also report experimental evidence for sex pheromones that reciprocally stimulate sexualization of compatible clones and orientate motility of the male gametes after an initial 'random walk'. CONCLUSIONS/SIGNIFICANCE: The threads superficially resemble flagella, in that both are produced by male gametes and contain microtubules. However, one striking difference is that threads cannot beat or undulate and have no motility of their own, and they do not bear mastigonemes. Threads are sticky and catch and draw objects, including eggs. The motility conferred by the threads is probably crucial for sexual reproduction of P. trainorii, because this diatom is non-motile in its vegetative stage but obligately outbreeding. Our pheromone experiments

  7. Stochastic volatility of volatility in continuous time

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole; Veraart, Almut

    This paper introduces the concept of stochastic volatility of volatility in continuous time and, hence, extends standard stochastic volatility (SV) models to allow for an additional source of randomness associated with greater variability in the data. We discuss how stochastic volatility...... of volatility can be defined both non-parametrically, where we link it to the quadratic variation of the stochastic variance process, and parametrically, where we propose two new SV models which allow for stochastic volatility of volatility. In addition, we show that volatility of volatility can be estimated...

  8. Irradiated boll weevils: pheromone production determined by GLC analysis

    International Nuclear Information System (INIS)

    McGovern, W.L.; McKibben, G.H.; Gueldner, R.C.; Cross, W.H.

    1975-01-01

    The production of pheromone by Anthonomus grandis Boheman when treated with 10,000 rad of 60 Co gamma irradiation compared favorably with that of control weevils for 5 days; however, feeding (determined by frass collection) was reduced from day one. No direct correlation was found between production of pheromone and elimination of frass

  9. Pheromone and Animal Reproducton: Speciation in Response to ...

    African Journals Online (AJOL)

    While humans are highly dependent upon visual cues when in close proximity, smell also play a big role in sociosexual behaviours. There is an inherent difficulty in studying human pheromones because of the need for cleanliness and odourlessness in human participants. Pheromones are often divided by function into two: ...

  10. With or without pheromone habituation: possible differences between insect orders?

    Science.gov (United States)

    Suckling, David Maxwell; Stringer, Lloyd D; Jiménez-Pérez, Alfredo; Walter, Gimme H; Sullivan, Nicola; El-Sayed, Ashraf M

    2018-06-01

    Habituation to sex pheromones is one of the key mechanisms in mating disruption, an insect control tactic. Male moths often show reduced sexual response after pre-exposure to female sex pheromone. Mating disruption is relatively rare in insect orders other than Lepidoptera. As a positive control we confirmed habituation in a moth (Epiphyas postvittana) using 24 h pre-exposure to sex pheromone to reduce subsequent activation behaviour. We then tested the impact of pre-exposure to sex or trail pheromone on subsequent behavioural response with insects from three other orders. Similar pre-exposure for 24 h to either sex pheromone [Pseudococcus calceolariae (Homoptera) and apple leaf curling midge Dasineura mali (Diptera), or trail pheromone of Argentine ants (Linepithema humile (Hymenoptera)], followed by behavioural assay in clean air provided no evidence of habituation after pre-exposure in these latter cases. The moths alone were affected by pre-exposure to pheromone. For pests without habituation, sustained attraction to a point source may make lure and kill more economical. Improved knowledge of behavioural processes should lead to better success in pest management and mechanisms should be investigated further to inform studies and practical efforts generally enhancing effectiveness of pheromone-based management. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  11. Activity of male pheromone of Melanesian rhinoceros beetle Scapanes australis.

    Science.gov (United States)

    Rochat, Didier; Morin, Jean-Paul; Kakul, Titus; Beaudoin-Ollivier, Laurence; Prior, Robert; Renou, Michel; Malosse, Isabelle; Stathers, Tanya; Embupa, Sebastian; Laup, Samson

    2002-03-01

    Laboratory and field investigations were carried out to investigate the nature and role of the male pheromone emitted by the Dynast beetle Scapanes australis and to develop a mass trapping technique against this major coconut pest in Papua New Guinea. We report the biological data obtained from natural and synthetic pheromone, previously described as an 84:12:4 (w/w) mixture of 2-butanol (1), 3-hydoxy-2-butanone (2), and 2,3-butanediol (3). EAG recordings from natural and synthetic pheromone and a pitfall olfactometer were poorly informative. In contrast, extensive field trapping trials with various synthetic pheromone mixtures and doses showed that 1 and 2 (formulated in polyethylene sachets in 90:5 v/v ratio) were necessary and sufficient for optimum long-range attraction. Beetles were captured in traps baited with racemic 1 plus 2, with or without a stereoisomer mixture of 3 (2.5- to 2500-mg/day doses). Plant pieces, either sugarcane or coconut, enhanced captures by the synthetic pheromone, which was active alone. Traps with the pheromone caught both sexes in a 3:2 female-male ratio. A pheromone-based mass trapping led to the capture of 2173 beetles in 14 traps surrounding 40 ha of a cocoa-coconut plantation. The captures followed a log-linear decrease during the 125-week trapping program. The role of the male pheromone and its potential for crop protection are discussed.

  12. Semi-selective fatty acyl reductases from four heliothine moths influence the specific pheromone composition

    NARCIS (Netherlands)

    Hagström, Å.K; Liénard, M.A.; Groot, A.T.; Hedenström, E; Löfstedt, C.

    2012-01-01

    Background: Sex pheromones are essential in moth mate communication. Information on pheromone biosynthetic genes and enzymes is needed to comprehend the mechanisms that contribute to specificity of pheromone signals. Most heliothine moths use sex pheromones with (Z)-11-hexadecenal as the major

  13. Lack of spatial segregation in the representation of pheromones and kairomones in the mouse medial amygdala.

    Directory of Open Access Journals (Sweden)

    Vinicius Miessler de Andrade Carvalho

    2015-08-01

    Full Text Available The nervous system is organized to detect, internally represent and process sensory information to generate appropriate behaviors. Despite the crucial importance of odors that elicit instinctive behaviors, such as pheromones and kairomones, their neural representation remains little characterized in the mammalian brain. Here we used expression of the immediate early gene product c-Fos as a marker of neuronal activity to find that a wide range of pheromones and kairomones produces activation in the medial nucleus of the amygdala, a brain area anatomically connected with the olfactory sensory organs. We see that activity in this nucleus depends on vomeronasal organ input, and that distinct vomeronasal stimuli activate a dispersed ensemble of cells, without any apparent spatial segregation. This activity pattern does not reflect the chemical category of the stimuli, their valence or the induced behaviors. These findings will help build a complete understanding of how odor information is processed in the brain to generate instinctive behaviors.

  14. Aggregation pheromone of coconut rhinoceros beetle,Oryctes rhinoceros (L.) (coleoptera: Scarabaeidae).

    Science.gov (United States)

    Hallett, R H; Perez, A L; Gries, G; Gries, R; Pierce, H D; Yue, J; Oehlschlager, A C; Gonzalez, L M; Borden, J H

    1995-10-01

    Male coconut rhinoceros beetles,Oryctes rhinoceros (L.), produce three sex-specific compounds, ethyl 4-methyloctanoate, ethyl 4-methylheptanoate, and 4-methyloctanoic acid, the first of which is an aggregation pheromone. Synthesis of these compounds involving conjugate addition of organocuprates to ethyl acrylate is reported. In field trapping experiments, (4S)-ethyl 4-methyloctanoate and the racemic mixture were equally attractive and 10 times more effective in attracting beetles than ethyl chrysanthemumate, a previously recommended attractant. Ethyl 4-methylheptanoate was as attractive as ethyl chrysanthemumate and more attractive than 4-methyloctanoic acid, but further studies are required before it can be classed as an aggregation pheromone. Compared to ethyl 4-methyloctanoate alone, combinations of the three male-produced compounds did not increase attraction, whereas addition of freshly rotting oil palm fruit bunches to pheromone-baited traps significantly enhanced attraction. With increasing dose, captures ofO. rhinoceros increased, but doses of 6, 9, and 18 mg/day were competitive with 30 mg/day lures. Newly designed vane traps were more effective in capturing beetles than were barrier or pitfall traps. Results of this study indicate that there is potential for using ethyl 4-methyloctanoate in operational programs to controlO. rhinoceros in oil palm plantations.

  15. Pheromone-based disruption of Eucosma sonomana and Rhyacionia zozana (Lepidoptera: Tortricidae) using aerially applied microencapsulated pheromone

    Science.gov (United States)

    Nancy E. Gillette; John D. Stein; Donald R. Owen; Jeffrey N. Webster; Sylvia R. Mori

    2006-01-01

    Two aerial applications of microencapsulated pheromone were conducted on five 20.2 ha plots to disrupt western pine shoot borer (Eucosma sonomana Kearfott) and ponderosa pine tip moth (Rhyacionia zowna (Kearfott): Lepidoptera: Tortricidae) orientation to pheromones and oviposition in ponderosa pine plantations in 2002 and 2004...

  16. Evaluating the binding efficiency of pheromone binding protein with its natural ligand using molecular docking and fluorescence analysis

    Science.gov (United States)

    Ilayaraja, Renganathan; Rajkumar, Ramalingam; Rajesh, Durairaj; Muralidharan, Arumugam Ramachandran; Padmanabhan, Parasuraman; Archunan, Govindaraju

    2014-06-01

    Chemosignals play a crucial role in social and sexual communication among inter- and intra-species. Chemical cues are bound with protein that is present in the pheromones irrespective of sex are commonly called as pheromone binding protein (PBP). In rats, the pheromone compounds are bound with low molecular lipocalin protein α2u-globulin (α2u). We reported farnesol is a natural endogenous ligand (compound) present in rat preputial gland as a bound volatile compound. In the present study, an attempt has been made through computational method to evaluating the binding efficiency of α2u with the natural ligand (farnesol) and standard fluorescent molecule (2-naphthol). The docking analysis revealed that the binding energy of farnesol and 2-naphthol was almost equal and likely to share some binding pocket of protein. Further, to extrapolate the results generated through computational approach, the α2u protein was purified and subjected to fluorescence titration and binding assay. The results showed that the farnesol is replaced by 2-naphthol with high hydrophobicity of TYR120 in binding sites of α2u providing an acceptable dissociation constant indicating the binding efficiency of α2u. The obtained results are in corroboration with the data made through computational approach.

  17. Enterococcus faecalis Sex Pheromone cCF10 Enhances Conjugative Plasmid Transfer In Vivo.

    Science.gov (United States)

    Hirt, Helmut; Greenwood-Quaintance, Kerryl E; Karau, Melissa J; Till, Lisa M; Kashyap, Purna C; Patel, Robin; Dunny, Gary M

    2018-02-13

    Cell-cell communication mediated by peptide pheromones (cCF10 [CF]) is essential for high-frequency plasmid transfer in vitro in Enterococcus faecalis To examine the role of pheromone signaling in vivo , we established either a CF-producing (CF+) recipient or a recipient producing a biologically inactive variant of CF (CF- recipient) in a germfree mouse model 3 days before donor inoculation and determined transfer frequencies of the pheromone-inducible plasmid pCF10. Plasmid transfer was detected in the upper and middle sections of the intestinal tract 5 h after donor inoculation and was highly efficient in the absence of antibiotic selection. The transconjugant/donor ratio reached a maximum level approaching 1 on day 4 in the upper intestinal tract. Plasmid transfer was significantly lower with the CF- recipient. While rescue of the CF- mating defect by coculture with CF+ recipients is easily accomplished in vitro , no extracellular complementation occurred in vivo This suggests that most pheromone signaling in the gut occurs between recipient and donor cells in very close proximity. Plasmid-bearing cells (donors plus transconjugants) steadily increased in the population from 0.1% after donor inoculation to about 10% at the conclusion of the experiments. This suggests a selective advantage of pCF10 carriage distinct from antibiotic resistance or bacteriocin production. Our results demonstrate that pheromone signaling is required for efficient pCF10 transfer in vivo In the absence of CF+ recipients, a low level of transfer to CF- recipients occurred in the gut. This may result from low-level host-mediated induction of the donors in the gastrointestinal (GI) tract, similar to that previously observed in serum. IMPORTANCE Horizontal gene transfer is a major factor in the biology of Enterococcus faecalis , an important nosocomial pathogen. Previous studies showing efficient conjugative plasmid transfer in the gastrointestinal (GI) tracts of experimental animals did

  18. Studies on aerosols. XI. Influence of particulate matter on the eye irritation produced by volatile irritants and importance of particle size in connection with atmospheric pollution

    Energy Technology Data Exchange (ETDEWEB)

    Dautrebande, L; Shaver, J; Capps, R

    1951-01-01

    This is a review of smog irritation prevented by water filters which remove > 2-..mu..m particles. Formaldehyde, HNO/sub 3/, H/sub 2/SO/sub 4/ vapors combined plus used oil produced stronger irritation than vapors alone. Vapors produced irritation essentially only at concentrations above 4.2 x 10/sup -3/ mg/liter air of each constituent. Three trained human volunteers were exposed to various aerosols via goggles. Blinking and lacrimation were observed. Reaction varied largely between the 3 and between different exposure periods. NaCl, Si dust, and used oil in combination required a much higher concentration to produce eye irritation than with vapors present. NaCl and Si combined did not irritate; used oil did. Photomicrographs showed small (approx. 0.05 ..mu..m), long-chained (1 to 7 ..mu..m), and aggregated (1 to 10 ..mu..m) particles.

  19. Saproxylic community, guild and species responses to varying pheromone components of a pine bark beetle.

    Science.gov (United States)

    Etxebeste, Iñaki; Lencina, José L; Pajares, Juan

    2013-10-01

    Some bark beetle species (Coleoptera: Scolytinae) produce aggregation pheromones that allow coordinated attack on their conifer hosts. As a new saproxylic habitat is founded, an assemblage of associated beetles kairomonally respond to bark beetle infochemicals. Ips sexdentatus is one of the major damaging insects of Pinus spp. in Southern Europe. Its response to varying ipsenol (Ie) percentages in relation to ipsdienol (Id) was studied in northwestern Spain, along with the entire saproxylic beetle assemblage captured at multiple-funnel traps. Response profile modeling was undertaken for I. sexdentatus sexes and sex-ratios, associated species and for selected trophic groups using a reference Gaussian model. In addition, the effects on the saproxylic assemblages were analyzed. I. sexdentatus response curve peaked at 22.7% Ie content, while remaining taxa that could be modeled, peaked above ca. 40% Ie. Predator guilds showed a linear relationship with Ie proportion, while competitors showed a delayed response peak. Consequently, species assemblages differed markedly between varying pheromone component mixtures. Given that the evaluated pheromonal proportions mimicked that of logs being colonized by I. sexdentatus, results suggested that the registered differential responses at different levels might provide I. sexdentatus with a temporal window that maximizes conspecific attraction while reducing interference with competitor and predatory guilds. Described responses might help improve the monitoring of the population status of target bark beetles and their associates, but also point toward the by-catch of many natural enemies, as well as rare saproxylic beetle species, interfering with the aims of sustainable forest management.

  20. Specialized odorant receptors in social insects that detect cuticular hydrocarbon cues and candidate pheromones.

    Science.gov (United States)

    Pask, Gregory M; Slone, Jesse D; Millar, Jocelyn G; Das, Prithwiraj; Moreira, Jardel A; Zhou, Xiaofan; Bello, Jan; Berger, Shelley L; Bonasio, Roberto; Desplan, Claude; Reinberg, Danny; Liebig, Jürgen; Zwiebel, Laurence J; Ray, Anandasankar

    2017-08-17

    Eusocial insects use cuticular hydrocarbons as components of pheromones that mediate social behaviours, such as caste and nestmate recognition, and regulation of reproduction. In ants such as Harpegnathos saltator, the queen produces a pheromone which suppresses the development of workers' ovaries and if she is removed, workers can transition to a reproductive state known as gamergate. Here we functionally characterize a subfamily of odorant receptors (Ors) with a nine-exon gene structure that have undergone a massive expansion in ants and other eusocial insects. We deorphanize 22 representative members and find they can detect cuticular hydrocarbons from different ant castes, with one (HsOr263) that responds strongly to gamergate extract and a candidate queen pheromone component. After systematic testing with a diverse panel of hydrocarbons, we find that most Harpegnathos saltator Ors are narrowly tuned, suggesting that several receptors must contribute to detection and discrimination of different cuticular hydrocarbons important in mediating eusocial behaviour.Cuticular hydrocarbons (CHC) mediate the interactions between individuals in eusocial insects, but the sensory receptors for CHCs are unclear. Here the authors show that in ants such as H. saltator, the 9-exon subfamily of odorant receptors (HsOrs) responds to CHCs, and ectopic expression of HsOrs in Drosophila neurons imparts responsiveness to CHCs.

  1. Characteristic odor of Osmoderma eremita identified as a male-released pheromone.

    Science.gov (United States)

    Larsson, Mattias C; Hedin, Jonas; Svensson, Glenn P; Tolasch, Till; Francke, Wittko

    2003-03-01

    Osmoderma eremita (Scopoli) is an endangered scarab beetle living in hollow trees. It has mainly been known for its characteristic odor, typically described as a fruity, peachlike or plumlike aroma. The odor emanating from a single beetle can sometimes be perceived from a distance of several meters. In this paper, we show that the characteristic odor from O. eremita is caused by the compound (R)-(+)-gamma-decalactone, released in large quantities mainly or exclusively by male beetles. Antennae from male and female beetles responded in a similar way to (R)-(+)-gamma-decalactone in electroantennographic recordings. Field trapping experiments showed that (R)-(+)-gamma-decalactone is a pheromone attracting female beetles. Lactones similar to (R)-(+)-gamma-decalactone are frequently used as female-released sex pheromones by phytophagous scarabs. This is, however, the first evidence of a lactone used as a male-produced pheromone in scarab beetles. We propose that the strong signal from males is a sexually selected trait used to compete for females and matings. The signal could work within trees but also act as a guide to tree hollows, which are an essential resource for O. eremita. Males may, thus, attract females dispersing from their natal tree by advertising a suitable habitat. This signal could also be exploited by other males searching for tree hollows or for females, which would explain the catch of several males in our traps.

  2. Nectar Attracts Foraging Honey Bees with Components of Their Queen Pheromones.

    Science.gov (United States)

    Liu, Fanglin; Gao, Jie; Di, Nayan; Adler, Lynn S

    2015-11-01

    Floral nectar often contains chemicals that are deterrent to pollinators, presenting potential challenges to outcrossing plant species. Plants may be able to co-opt pollinator chemical signals to mitigate the negative effects of nectar deterrent compounds on pollination services. We found that buckwheat (Fagopyrum esculentum) and Mexican sunflower (Tithonia diversifolia) produce nectar with abundant phenolics, including three components of the Apis honeybee queen mandibular pheromone (QMP). In addition, these nectars contain a non-pheromonal phenolic, chlorogenic acid (CA), which was toxic to honeybees, and T. diversifolia nectar also contained isochlorogenic acid (IA). Fresh nectar or solutions containing nectar phenolics reduced Apis individual feeding compared to sucrose solutions. However, freely foraging bees preferred solutions with QMP components to control solutions, and QMP components over-rode or reversed avoidance of CA and IA. Furthermore, prior exposure to the presence or just the odor of QMP components removed the deterrent effects of CA and IA. By mimicking the honey bee pheromone blend, nectar may maintain pollinator attraction in spite of deterrent nectar compounds.

  3. Insectivorous birds eavesdrop on the pheromones of their prey.

    Science.gov (United States)

    Saavedra, Irene; Amo, Luisa

    2018-01-01

    Chemical cues play a fundamental role in mate attraction and mate choice. Lepidopteran females, such as the winter moth (Operophtera brumata), emit pheromones to attract males in the reproductive period. However, these chemical cues could also be eavesdropped by predators. To our knowledge, no studies have examined whether birds can detect pheromones of their prey. O. brumata adults are part of the winter diet of some insectivorous tit species, such as the great tit (Parus major) and blue tit (Cyanistes caeruleus). We performed a field experiment aimed to disentangle whether insectivorous birds can exploit the pheromones emitted by their prey for prey location. We placed artificial larvae and a dispenser on branches of Pyrenean oak trees (Quercus pyrenaica). In half of the trees we placed an O. brumata pheromone dispenser and in the other half we placed a control dispenser. We measured the predation rate of birds on artificial larvae. Our results show that more trees had larvae with signs of avian predation when they contained an O. brumata pheromone than when they contained a control dispenser. Furthermore, the proportion of artificial larvae with signs of avian predation was greater in trees that contained the pheromone than in control trees. Our results indicate that insectivorous birds can exploit the pheromones emitted by moth females to attract males, as a method of prey detection. These results highlight the potential use of insectivorous birds in the biological control of insect pests.

  4. Olfactory effects of a hypervariable multicomponent pheromone in the red-legged salamander, Plethodon shermani.

    Directory of Open Access Journals (Sweden)

    Damien B Wilburn

    Full Text Available Chemical communication via chemosensory signaling is an essential process for promoting and modifying reproductive behavior in many species. During courtship in plethodontid salamanders, males deliver a mixture of non-volatile proteinaceous pheromones that activate chemosensory neurons in the vomeronasal epithelium (VNE and increase female receptivity. One component of this mixture, Plethodontid Modulating Factor (PMF, is a hypervariable pheromone expressed as more than 30 unique isoforms that differ between individual males-likely driven by co-evolution with female receptors to promote gene duplication and positive selection of the PMF gene complex. Courtship trials with females receiving different PMF isoform mixtures had variable effects on female mating receptivity, with only the most complex mixtures increasing receptivity, such that we believe that sufficient isoform diversity allows males to improve their reproductive success with any female in the mating population. The aim of this study was to test the effects of isoform variability on VNE neuron activation using the agmatine uptake assay. All isoform mixtures activated a similar number of neurons (>200% over background except for a single purified PMF isoform (+17%. These data further support the hypothesis that PMF isoforms act synergistically in order to regulate female receptivity, and different putative mechanisms are discussed.

  5. Molecular characterization of pheromone biosynthesis activating neuropeptide from the diamondback moth, Plutella xylostella (L.).

    Science.gov (United States)

    Lee, Dae-Weon; Boo, Kyung Saeng

    2005-12-01

    Pheromone biosynthesis activating neuropeptide (PBAN) produced in the subesophageal ganglion stimulates pheromone production in the pheromone gland. A cDNA isolated from female adult heads of the diamondback moth (Plutella xylostella (L.)) encodes 193 amino acids including PBAN, designated as Plx-PBAN, and four other neuropeptides (NPs): diapause hormone (DH) homologue, alpha-NP, beta-NP and gamma-NP. All of the peptides are amidated in their C-termini and shared a conserved motif, FXPR(or K)L structure, as reported from other PBAN cDNAs. Plx-PBAN consists of 30 amino acids, the shortest PBAN so far reported. Plx-PBAN exhibited below 50% homology, compared with other known PBANs. The Plx-DH homologue is structurally different from DH of Bombyx mori. The length of Plx-beta-NP (16 amino acids) was the shortest and showed relatively low similarity, whereas gamma-NP (10 amino acids in length) was the longest among examined gamma-NPs. When female adults were injected with synthetic Plx-PBAN, pheromone production showed a maximal increase 1h post-injection. RT-PCR screening revealed that Plx-PBAN cDNA was expressed in all examined body parts, with the highest expression level in the head of female adults. Analysis of RT-PCR products indicated the Plx-PBAN sequence was identical in all examined body parts of both sexes. Phylogenetic analysis revealed that the Plx-PBAN gene is distantly related to other PBANs, demonstrated by the relatively low similarity.

  6. Effects of pH control and concentration on microbial oil production from Chlorella vulgaris cultivated in the effluent of a low-cost organic waste fermentation system producing volatile fatty acids.

    Science.gov (United States)

    Cho, Hyun Uk; Kim, Young Mo; Choi, Yun-Nam; Xu, Xu; Shin, Dong Yun; Park, Jong Moon

    2015-05-01

    The objective of this study was to investigate the feasibility of applying volatile fatty acids (VFAs) produced from low-cost organic waste to the major carbon sources of microalgae cultivation for highly efficient biofuel production. An integrated process that consists of a sewage sludge fermentation system producing VFAs (SSFV) and mixotrophic cultivation of Chlorella vulgaris (C. vulgaris) was operated to produce microbial lipids economically. The effluents from the SSFV diluted to different concentrations at the level of 100%, 50%, and 15% were prepared for the C. vulgaris cultivation and the highest biomass productivity (433±11.9 mg/L/d) was achieved in the 100% culture controlling pH at 7.0. The harvested biomass included lipid contents ranging from 12.87% to 20.01% under the three different effluent concentrations with and without pH control. The composition of fatty acids from C. vulgaris grown on the effluents from the SSFV complied with the requirements of high-quality biodiesel. These results demonstrated that VFAs produced from the SSFV are favorable carbon sources for cultivating C. vulgaris. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Strain of Fusarium oxysporum Isolated From Almond Hulls Produces Styrene and 7-Methyl-1,3,5-Cyclooctatriene as the Principal Volatile Components

    Science.gov (United States)

    An isolated strain of Fusarium oxysporum from the hulls of Prunus dulcis (sweet almond) was found to produce relatively large quantities of the hydrocarbons styrene and three isomers of 7-methyl-1,3,5-cyclooctatriene (MCOT). Production of styrene and MCOT was reproduced on small scale using potato d...

  8. Silent genes and rare males: A fresh look at pheromone blend response specificity in the European corn borer moth, Ostrinia nubilalis

    Directory of Open Access Journals (Sweden)

    Charles Linn Jr.

    2003-05-01

    Full Text Available The response of male moths from two pheromone races of the European corn borer, Ostrinia nubilalis, was measured in a flight tunnel assay to different ratios of structurally different compounds that comprise the sex pheromone of the Asian corn borer, Ostrinia furnacalis. For both O. nubilalis races, between 1 and 5% of the males completed upwind flights to two different blends of the O. furnacalis pheromone components (the 2:1 Z/E12-14:OAc female-produced blend, and a 97:3 Z/E mix, confirming that rare males exist in the O. nubilalis populations that can detect and respond to mixtures of the O. furnacalis pheromone components. Rare males that responded to the O. furnacalis blends also responded to their own O. nubilalis blends (97:3 or 1:99 Z/E11-14:OAc, indicating that rare O. nubilalis males are not preferentially sensitive to mixtures of the O. furnacalis compounds, but rather that they have a broad range of response specificity, which includes recognition of a wide range of conspecific female-produced ratios, and also recognition of heterospecific mixtures. The results support the hypothesis that saltational shifts in pheromone blend composition (Roelofs et al., 2002 can lead to the evolution of a new species-specific communication system, in part because the broad response specificity of some males includes the ability to respond in an agonistic manner to novel mixtures of compounds.

  9. Functionality of the Paracoccidioides mating α-pheromone-receptor system.

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    Jéssica A Gomes-Rezende

    Full Text Available Recent evidence suggests that Paracoccidioides species have the potential to undergo sexual reproduction, although no sexual cycle has been identified either in nature or under laboratory conditions. In the present work we detected low expression levels of the heterothallic MAT loci genes MAT1-1 and MAT1-2, the α-pheromone (PBα gene, and the α- and a-pheromone receptor (PREB and PREA genes in yeast and mycelia forms of several Paracoccidioides isolates. None of the genes were expressed in a mating type dependent manner. Stimulation of P. brasiliensis MAT1-2 strains with the synthetic α-pheromone peptide failed to elicit transcriptional activation of MAT1-2, PREB or STE12, suggesting that the strains tested are insensitive to α-pheromone. In order to further evaluate the biological functionality of the pair α-pheromone and its receptor, we took advantage of the heterologous expression of these Paracoccidioides genes in the corresponding S. cerevisiae null mutants. We show that S. cerevisiae strains heterologously expressing PREB respond to Pbα pheromone either isolated from Paracoccidioides culture supernatants or in its synthetic form, both by shmoo formation and by growth and cell cycle arrests. This allowed us to conclude that Paracoccidioides species secrete an active α-pheromone into the culture medium that is able to activate its cognate receptor. Moreover, expression of PREB or PBα in the corresponding null mutants of S. cerevisiae restored mating in these non-fertile strains. Taken together, our data demonstrate pheromone signaling activation by the Paracoccidioides α-pheromone through its receptor in this yeast model, which provides novel evidence for the existence of a functional mating signaling system in Paracoccidioides.

  10. Genomewide identification of pheromone-targeted transcription in fission yeast

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    Wright Anthony

    2006-11-01

    Full Text Available Abstract Background Fission yeast cells undergo sexual differentiation in response to nitrogen starvation. In this process haploid M and P cells first mate to form diploid zygotes, which then enter meiosis and sporulate. Prior to mating, M and P cells communicate with diffusible mating pheromones that activate a signal transduction pathway in the opposite cell type. The pheromone signalling orchestrates mating and is also required for entry into meiosis. Results Here we use DNA microarrays to identify genes that are induced by M-factor in P cells and by P-factor in M-cells. The use of a cyr1 genetic background allowed us to study pheromone signalling independently of nitrogen starvation. We identified a total of 163 genes that were consistently induced more than two-fold by pheromone stimulation. Gene disruption experiments demonstrated the involvement of newly discovered pheromone-induced genes in the differentiation process. We have mapped Gene Ontology (GO categories specifically associated with pheromone induction. A direct comparison of the M- and P-factor induced expression pattern allowed us to identify cell-type specific transcripts, including three new M-specific genes and one new P-specific gene. Conclusion We found that the pheromone response was very similar in M and P cells. Surprisingly, pheromone control extended to genes fulfilling their function well beyond the point of entry into meiosis, including numerous genes required for meiotic recombination. Our results suggest that the Ste11 transcription factor is responsible for the majority of pheromone-induced transcription. Finally, most cell-type specific genes now appear to be identified in fission yeast.

  11. Nutrient-dependent/pheromone-controlled adaptive evolution: a model

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    James Vaughn Kohl

    2013-06-01

    Full Text Available Background: The prenatal migration of gonadotropin-releasing hormone (GnRH neurosecretory neurons allows nutrients and human pheromones to alter GnRH pulsatility, which modulates the concurrent maturation of the neuroendocrine, reproductive, and central nervous systems, thus influencing the development of ingestive behavior, reproductive sexual behavior, and other behaviors. Methods: This model details how chemical ecology drives adaptive evolution via: (1 ecological niche construction, (2 social niche construction, (3 neurogenic niche construction, and (4 socio-cognitive niche construction. This model exemplifies the epigenetic effects of olfactory/pheromonal conditioning, which alters genetically predisposed, nutrient-dependent, hormone-driven mammalian behavior and choices for pheromones that control reproduction via their effects on luteinizing hormone (LH and systems biology. Results: Nutrients are metabolized to pheromones that condition behavior in the same way that food odors condition behavior associated with food preferences. The epigenetic effects of olfactory/pheromonal input calibrate and standardize molecular mechanisms for genetically predisposed receptor-mediated changes in intracellular signaling and stochastic gene expression in GnRH neurosecretory neurons of brain tissue. For example, glucose and pheromones alter the hypothalamic secretion of GnRH and LH. A form of GnRH associated with sexual orientation in yeasts links control of the feedback loops and developmental processes required for nutrient acquisition, movement, reproduction, and the diversification of species from microbes to man. Conclusion: An environmental drive evolved from that of nutrient ingestion in unicellular organisms to that of pheromone-controlled socialization in insects. In mammals, food odors and pheromones cause changes in hormones such as LH, which has developmental affects on pheromone-controlled sexual behavior in nutrient-dependent reproductively

  12. Chemical profiles of two pheromone glands are differentially regulated by distinct mating factors in honey bee queens (Apis mellifera L..

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    Elina L Niño

    Full Text Available Pheromones mediate social interactions among individuals in a wide variety of species, from yeast to mammals. In social insects such as honey bees, pheromone communication systems can be extraordinarily complex and serve to coordinate behaviors among many individuals. One of the primary mediators of social behavior and organization in honey bee colonies is queen pheromone, which is produced by multiple glands. The types and quantities of chemicals produced differ significantly between virgin and mated queens, and recent studies have suggested that, in newly mated queens, insemination volume or quantity can affect pheromone production. Here, we examine the long-term impact of different factors involved during queen insemination on the chemical composition of the mandibular and Dufour's glands, two of the major sources of queen pheromone. Our results demonstrate that carbon dioxide (an anesthetic used in instrumental insemination, physical manipulation of genital tract (presumably mimicking the act of copulation, insemination substance (saline vs. semen, and insemination volume (1 vs. 8 µl all have long-term effects on mandibular gland chemical profiles. In contrast, Dufour's gland chemical profiles were changed only upon insemination and were not influenced by exposure to carbon dioxide, manipulation, insemination substance or volume. These results suggest that the chemical contents of these two glands are regulated by different neuro-physiological mechanisms. Furthermore, workers responded differently to the different mandibular gland extracts in a choice assay. Although these studies must be validated in naturally mated queens of varying mating quality, our results suggest that while the chemical composition of Dufour's gland is associated with mating status, that of the mandibular glands is associated with both mating status and insemination success. Thus, the queen appears to be signaling both status and reproductive quality to the workers

  13. Genome-Scale Analysis Reveals Sst2 as the Principal Regulator of Mating Pheromone Signaling in the Yeast Saccharomyces cerevisiae†

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    Chasse, Scott A.; Flanary, Paul; Parnell, Stephen C.; Hao, Nan; Cha, Jiyoung Y.; Siderovski, David P.; Dohlman, Henrik G.

    2006-01-01

    A common property of G protein-coupled receptors is that they become less responsive with prolonged stimulation. Regulators of G protein signaling (RGS proteins) are well known to accelerate G protein GTPase activity and do so by stabilizing the transition state conformation of the G protein α subunit. In the yeast Saccharomyces cerevisiae there are four RGS-homologous proteins (Sst2, Rgs2, Rax1, and Mdm1) and two Gα proteins (Gpa1 and Gpa2). We show that Sst2 is the only RGS protein that binds selectively to the transition state conformation of Gpa1. The other RGS proteins also bind Gpa1 and modulate pheromone signaling, but to a lesser extent and in a manner clearly distinct from Sst2. To identify other candidate pathway regulators, we compared pheromone responses in 4,349 gene deletion mutants representing nearly all nonessential genes in yeast. A number of mutants produced an increase (sst2, bar1, asc1, and ygl024w) or decrease (cla4) in pheromone sensitivity or resulted in pheromone-independent signaling (sst2, pbs2, gas1, and ygl024w). These findings suggest that Sst2 is the principal regulator of Gpa1-mediated signaling in vivo but that other proteins also contribute in distinct ways to pathway regulation. PMID:16467474

  14. Changes of sex pheromone communication systems associated with tebufenozide and abamectin resistance in diamondback moth, Plutella xylostella (L.).

    Science.gov (United States)

    Xu, Zhen; Cao, Guang-Chun; Dong, Shuang-Lin

    2010-05-01

    Many insect pests have evolved resistance to insecticides. Along with this evolution, the sex pheromone communication system of insects also may change, and subsequently reproductive isolation may occur between resistant and susceptible populations. In this study of the diamondback moth, we found that resistant females (especially Abamectin resistant females) produced less sex pheromone and displayed a lower level of calling behavior. Resistant males showed higher EAG responsiveness to the sex pheromone mixture of females, and responded to a broader range of ratios between the two major components compared to the responses of susceptible moths. In addition, wind tunnel experiments indicated that changes associated with insecticide resistance in the Abamectin resistant strain (Aba-R) significantly reduced female attractiveness to susceptible males. Furthermore, mating choice experiments confirmed that non-random mating occurred between the two different strains. Aba-R females with an abnormal pheromone production and blend ratio exhibited significantly lower mating percentages with males from either their own strain or other strains, which corroborates the results obtained by the wind tunnel experiments. The implications of this non-random mating for insect speciation and insecticide resistance management are discussed.

  15. Optimum timing of insecticide applications against diamondback moth Plutella xylostella in cole crops using threshold catches in sex pheromone traps.

    Science.gov (United States)

    Reddy, G V; Guerrero, A

    2001-01-01

    Field trials were conducted in cabbage (Brassica oleracea var capitata), cauliflower (B oleracea var botrytis) and knol khol (B oleracea gongylodes) crops at two different locations in Karnataka State (India) to optimize the timing of insecticide applications to control the diamondback moth, Plutella xylostella, using sex pheromone traps. Our results indicate that applications of cartap hydrochloride as insecticide during a 12-24 h period after the pheromone traps had caught on average 8, 12 and 16 males per trap per night in cabbage, cauliflower and knol khol, respectively, were significantly more effective than regular insecticide sprays at 7, 9, 12 or 15 days after transplantation. This was demonstrated by estimation of the mean number of eggs and larvae per plant, the percentage of holes produced, as well as the marketable yield of the three crops at each location. A good correlation between the immature stages, infestation level, the estimated crop yield and the number of moths caught in pheromone traps was also found, indicating the usefulness of pheromone-based monitoring traps to predict population densities of the pest.

  16. A queen pheromone induces workers to kill sexual larvae in colonies of the red imported fire ant (Solenopsis invicta)

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    Klobuchar, Emily; Deslippe, Richard

    2002-05-01

    We conducted five bioassays to study how queens control the execution of sexual larvae by workers in colonies of the red imported fire ant, Solenopsis invicta. In each assay, subset colonies were made from many large polygyne colonies, and the 20 sexual larvae they contained were monitored over time. Sexual larvae mostly survived in queenless colonies, but were mostly killed in colonies with a single dealated queen, regardless of whether or not the queen was fertilized. The larvae were also killed when fresh corpses of queens were added to queenless colonies. Whereas acetone extracts of queens did not produce a significant increase in killings, extracts in buffered saline induced workers to execute most sexual larvae, indicating successful extraction of an execution pheromone. We identified the probable storage location of the chemical as the poison sac, and found both fresh (1 day) and old (21 day) extracts of poison sacs to be equally effective in inducing executions. The pheromone is stable at room temperature, perhaps because venom alkaloids also present in the extracts keep the pheromone from degrading. It is apparently either proteinaceous or associated with a proteinaceous molecule, a novel finding, as no queen pheromone of a proteinaceous nature has been previously demonstrated in ants.

  17. Sex Attractant Pheromones of Virgin Queens of Sympatric Slave-Making Ant Species in the Genus Polyergus, and their Possible Roles in Reproductive Isolation.

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    Greenberg, Les; Johnson, Christine A; Trager, James C; McElfresh, J Steven; Rodstein, Joshua; Millar, Jocelyn G

    2018-06-01

    Species of the ant genus Polyergus are social parasites that steal brood from colonies of their hosts in the closely related genus Formica. Upon emergence as adults in a mixed population, host Formica workers carry out all the normal worker functions within the Polyergus colony, including foraging, feeding, grooming, and rearing brood of the parasitic Polyergus ants. Some unmated Polyergus gynes (queens) run in the raiding columns of their colonies and attract males by releasing a pheromone from their mandibular glands. There are two Polyergus species groups in North America: an eastern P. lucidus group and a western P. breviceps group. One species of each of these groups, P. lucidus Mayr and P. mexicanus Emery, are sympatric in Missouri. In this study, we characterized the sex pheromones of virgin queens of two species of the P. lucidus group (P. lucidus sensu stricto and P. sanwaldi) and one species of the P. breviceps group (P. mexicanus), and compared these with the previously identified sex pheromone of P. topoffi of the P. breviceps group. We then used sex pheromone blends reconstructed from synthesized components of the two groups to test their efficacy at reproductively isolating these species. We found that methyl 6-methylsalicylate is conserved as the major component of the pheromone blends for both Polyergus species groups; however, methyl (R)-3-ethyl-4-methylpentanoate is the species-specific minor component produced by P. lucidus group queens, and (R)-3-ethyl-4-methylpentan-1-ol is the crucial minor component for P. breviceps group queens. The optimal ratio of the major and minor components for P. lucidus group queens was about 100:1 salicylate to ester. In concurrent field trials in Missouri, males of P. lucidus sensu stricto and P. mexicanus (a member of the P. breviceps group) were attracted almost exclusively to their particular blends of sex pheromone components. To our knowledge, this is the first example of a possible sex-pheromone

  18. Discovery and characterization of natural products that act as pheromones in fish.

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    Li, Ke; Buchinger, Tyler J; Li, Weiming

    2018-06-20

    Covering: up to 2018 Fish use a diverse collection of molecules to communicate with conspecifics. Since Karlson and Lüscher termed these molecules 'pheromones', chemists and biologists have joined efforts to characterize their structures and functions. In particular, the understanding of insect pheromones developed at a rapid pace, set, in part, by the use of bioassay-guided fractionation and natural product chemistry. Research on vertebrate pheromones, however, has progressed more slowly. Initially, biologists characterized fish pheromones by screening commercially available compounds suspected to act as pheromones based upon their physiological function. Such biology-driven screening has proven a productive approach to studying pheromones in fish. However, the many functions of fish pheromones and diverse metabolites that fish release make predicting pheromone identity difficult and necessitate approaches led by chemistry. Indeed, the few cases in which pheromone identification was led by natural product chemistry indicated novel or otherwise unpredicted compounds act as pheromones. Here, we provide a brief review of the approaches to identifying pheromones, placing particular emphasis on the promise of using natural product chemistry together with assays of biological activity. Several case studies illustrate bioassay-guided fractionation as an approach to pheromone identification in fish and the unexpected diversity of pheromone structures discovered by natural product chemistry. With recent advances in natural product chemistry, bioassay-guided fractionation is likely to unveil an even broader collection of pheromone structures and enable research that spans across disciplines.

  19. Pricing Volatility Referenced Assets

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    Alan De Genaro Dario

    2006-12-01

    Full Text Available Volatility swaps are contingent claims on future realized volatility. Variance swaps are similar instruments on future realized variance, the square of future realized volatility. Unlike a plain vanilla option, whose volatility exposure is contaminated by its asset price dependence, volatility and variance swaps provide a pure exposure to volatility alone. This article discusses the risk-neutral valuation of volatility and variance swaps based on the framework outlined in the Heston (1993 stochastic volatility model. Additionally, the Heston (1993 model is calibrated for foreign currency options traded at BMF and its parameters are used to price swaps on volatility and variance of the BRL / USD exchange rate.

  20. Expression of the mevalonate pathway enzymes in the Lutzomyia longipalpis (Diptera: Psychodidae) sex pheromone gland demonstrated by an integrated proteomic approach.

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    González-Caballero, Natalia; Rodríguez-Vega, Andrés; Dias-Lopes, Geovane; Valenzuela, Jesus G; Ribeiro, Jose M C; Carvalho, Paulo Costa; Valente, Richard H; Brazil, Reginaldo P; Cuervo, Patricia

    2014-01-16

    In Latin America, Lutzomyia longipalpis is the main vector of the protozoan parasite Leishmania infantum, which is the causal agent of American Visceral Leishmaniasis. This insect uses male-produced pheromones for mate recognition. Elucidation of pheromone biogenesis or its regulation may enable molecular strategies for mating disruption and, consequently, the vector's population management. Motivated by our recent results of the transcriptomic characterization of the L. longipalpis pheromone gland, we performed a proteomic analysis of this tissue combining SDS-PAGE, and mass spectrometry followed by an integrative data analysis. Considering that annotated genome sequences of this sand fly are not available, we designed an alternative workflow searching MS/MS data against two customized databases using three search engines: Mascot, OMSSA and ProLuCID. A total of 542 proteins were confidently characterized, 445 of them using a Uniref100-insect protein database, and 97 using a transcript translated database. In addition, use of PEAKS for de novo peptide sequencing of MS/MS data confirmed ~90% identifications made with the combination of the three search engines. Our results include the identification of six of the seven enzymes of the mevalonate-pathway, plus the enzymes involved in sesquiterpenoid biosynthesis, all of which are proposed to be involved in pheromone production in L. longipalpis. L. longipalpis is the main vector of the protozoan parasite L. infantum, which is the causal agent of American Visceral Leishmaniasis. One of the control measures of such disease is focused on vector population control. As this insect uses male-produced pheromones for mate recognition, the elucidation of pheromone biogenesis or its regulating process may enable molecular strategies for mating disruption and, consequently, this vector's population management. On this regard, in this manuscript we report expression evidence, at the protein level, of several molecules potentially

  1. Directional Bias and Pheromone for Discovery and Coverage on Networks

    Energy Technology Data Exchange (ETDEWEB)

    Fink, Glenn A.; Berenhaut, Kenneth S.; Oehmen, Christopher S.

    2012-09-11

    Natural multi-agent systems often rely on “correlated random walks” (random walks that are biased toward a current heading) to distribute their agents over a space (e.g., for foraging, search, etc.). Our contribution involves creation of a new movement and pheromone model that applies the concept of heading bias in random walks to a multi-agent, digital-ants system designed for cyber-security monitoring. We examine the relative performance effects of both pheromone and heading bias on speed of discovery of a target and search-area coverage in a two-dimensional network layout. We found that heading bias was unexpectedly helpful in reducing search time and that it was more influential than pheromone for improving coverage. We conclude that while pheromone is very important for rapid discovery, heading bias can also greatly improve both performance metrics.

  2. Pheromones of milkweed bugs (Heteroptera: Lygaeidae) attract wayward plant bugs: Phytocoris mirid sex pheromone.

    Science.gov (United States)

    Zhang, Qing-He; Aldrich, Jeffrey R

    2003-08-01

    The synthetic aggregation pheromone of the large milkweed bug, Oncopeltus fasciatus (Dallas) (Lygaeinae), also attracted males of the plant bug, Phytocoris difficilis Knight (Miridae). Field testing partial blends against the six-component blend comprising the Oncopeltus pheromone showed that cross-attraction of P. difficilis males was due to synergism between (E)-2-octenyl acetate and (E,E)-2,4-hexadienyl acetate. Hexyl acetate was abundant in the metathoracic scent gland (MSG) secretion of P. difficilis males, but because female P. difficilis could not initially be found in the field, further combinatorial tests were guided by prior research on the pheromones of two Phytocoris species in the western United States. The combination of hexyl, (E)-2-hexenyl, and (E)-2-octenyl acetates was as attractive to P. difficilis males as the milkweed bug pheromone, yet no milkweed bugs were drawn to this blend. Gas chromatographic (GC)-electroantennographic detection (EAD) and GC-mass spectrometric (MS) analyses of female P. difficilis MSGs determined that their secretion contained predominantly hexyl, (E)-2-hexenyl, and (E)-2-octenyl acetates (all strongly EAD-active)-the latter two compounds found only in trace amounts from males-plus five minor female-specific compounds, three of which were EAD-active. (E,E)-2,4-Hexadienyl acetate was not detected from P. difficilis females or males. The blend of the three major components, hexyl, (E)-2-hexenyl, and (E)-2-octenyl acetates (2:1.5:1 by volume), was as attractive as the blend of all six EAD-active compounds identified from females, indicating that this ternary blend constitutes the sex pheromone of P. difficilis. Hexyl acetate with (E)-2-octenyl acetate also attracted males of another species, P. breviusculus Reuter, but addition of (E)-2-hexenyl acetate and/or (E,E)-2,4-hexadienyl acetate inhibited attraction of P. breviusculus males. Attraction of P. difficilis males occurred mainly during the first half of scotophase. The

  3. Trail Pheromone Disruption of Argentine Ant Trail Formation and Foraging

    Science.gov (United States)

    Suckling, D.M.; Peck, R.W.; Stringer, L.D.; Snook, K.; Banko, P.C.

    2010-01-01

    Trail pheromone disruption of invasive ants is a novel tactic that builds on the development of pheromone-based pest management in other insects. Argentine ant trail pheromone, (Z)-9-hexadecenal, was formulated as a micro-encapsulated sprayable particle and applied against Argentine ant populations in 400 m2 field plots in Hawai'i Volcanoes National Park. A widely dispersed point source strategy for trail pheromone disruption was used. Traffic rates of ants in bioassays of treated filter paper, protected from rainfall and sunlight, indicated the presence of behaviorally significant quantities of pheromone being released from the formulation for up to 59 days. The proportion of plots, under trade wind conditions (2-3 m s-1), with visible trails was reduced for up to 14 days following treatment, and the number of foraging ants at randomly placed tuna-bait cards was similarly reduced. The success of these trail pheromone disruption trials in a natural ecosystem highlights the potential of this method for control of invasive ant species in this and other environments. ?? Springer Science+Business Media, LLC 2010.

  4. Influence of host plants on sexual communication in the herbivorous bug Lygocoris pabulinus

    NARCIS (Netherlands)

    Groot, A.T.; Visser, J.H.

    2001-01-01

    Host plant volatiles may be involved in the sexual communication of insects in several ways. In the pheromone-producing sex, these volatiles may affect pheromone production or release and, in the receptive sex, plant volatiles may have a synergistic effect on the attraction to sex pheromone. We

  5. Novel synthetic compounds enhance the attractiveness of host-plant volatiles: An opportunity to boost detection and monitoring of Asian citrus psyllid?

    Science.gov (United States)

    In the absence of pheromone attractants, host-plant volatiles offer the most likely means of improving capture levels of Asian citrus psyllid (ACP) with sticky cards and other types of visual traps. However, developing scent lures that can compete with the attractiveness of actual host-plants, espe...

  6. Conditional deletion of ERK5 MAP kinase in the nervous system impairs pheromone information processing and pheromone-evoked behaviors.

    Directory of Open Access Journals (Sweden)

    Junhui Zou

    Full Text Available ERK5 MAP kinase is highly expressed in the developing nervous system but absent in most regions of the adult brain. It has been implicated in regulating the development of the main olfactory bulb and in odor discrimination. However, whether it plays an essential role in pheromone-based behavior has not been established. Here we report that conditional deletion of the Mapk7 gene which encodes ERK5 in mice in neural stem cells impairs several pheromone-mediated behaviors including aggression and mating in male mice. These deficits were not caused by a reduction in the level of testosterone, by physical immobility, by heightened fear or anxiety, or by depression. Using mouse urine as a natural pheromone-containing solution, we provide evidence that the behavior impairment was associated with defects in the detection of closely related pheromones as well as with changes in their innate preference for pheromones related to sexual and reproductive activities. We conclude that expression of ERK5 during development is critical for pheromone response and associated animal behavior in adult mice.

  7. Attraction of the southern pine beetle, Dendroctonus frontalis, to pheromone components of the western pine beetle, Dendroctonus brevicomis (Coleoptera: Curculionidae: Scolytinae), in an allopatric zone

    Science.gov (United States)

    Deepa S. Pureswaran; Richard W. Hofstetter; Brian T. Sullivan

    2008-01-01

    Subtle differences in pheromone components of sympatric species should be attractive only to the producing species and unattractive or repellent to the nonproducing species, and thereby maintain reproductive isolation and reduce competition between species. Bark beetles Dendroctonus brevicomis and D. frontalis (Coleoptera: Curculionidae) are known to...

  8. Evaluation of the antiaggregation pheromone, 3-methylcyclohex-2-en-1-one (MCH), to protect live spruce from spruce beetle (Coleoptera: Scolytidae) infestation in sourthern Utah.

    Science.gov (United States)

    Darrell W. Ross; Gary E. Daterman; A. Steven Munson

    2004-01-01

    The spruce beetle, Dendroctonus rufipennis (Kirby), produces the antiaggregation pheromone 3-methylcyclohex-2-en- 1-one (MCH) (Rudinsky et al. 1974). MCH has reduced the numbers of spruce beetles attracted to infested logs and synthetic semiochemical lures or reduced colonization rates throughout the beetles range (Kline

  9. Behavioural plasticity in support of a benefit for aggregation pheromone use in Drosophila melanogaster

    NARCIS (Netherlands)

    Wertheim, B.; Dicke, M.; Vet, L.E.M.

    2002-01-01

    We explored behavioural plasticity in the use of aggregation pheromone in the fruit fly Drosophila melanogaster Meigen (Diptera: Drosophilidae). Based on previous field observations, we formulated two hypotheses on a benefit of using aggregation pheromone for aggregated oviposition. One hypothesis

  10. Behavioural plasticity in support of a benefit for aggregation pheromone use in Drosophila melanogaster

    NARCIS (Netherlands)

    Wertheim, B; Dicke, Marcel; Vet, LEM

    We explored behavioural plasticity in the use of aggregation pheromone in the fruit fly Drosophila melanogaster Meigen (Diptera: Drosophilidae). Based on previous field observations, we formulated two hypotheses on a benefit of using aggregation pheromone for aggregated oviposition. One hypothesis

  11. Temperature limits trail following behaviour through pheromone decay in ants

    Science.gov (United States)

    van Oudenhove, Louise; Billoir, Elise; Boulay, Raphaël; Bernstein, Carlos; Cerdá, Xim

    2011-12-01

    In Mediterranean habitats, temperature affects both ant foraging behaviour and community structure. Many studies have shown that dominant species often forage at lower temperature than subordinates. Yet, the factors that constrain dominant species foraging activity in hot environments are still elusive. We used the dominant ant Tapinoma nigerrimum as a model species to test the hypothesis that high temperatures hinder trail following behaviour by accelerating pheromone degradation. First, field observations showed that high temperatures (> 30°C) reduce the foraging activity of T. nigerrimum independently of the daily and seasonal rhythms of this species. Second, we isolated the effect of high temperatures on pheromone trail efficacy from its effect on worker physiology. A marked substrate was heated during 10 min (five temperature treatments from 25°C to 60°C), cooled down to 25°C, and offered in a test choice to workers. At hot temperature treatments (>40°C), workers did not discriminate the previously marked substrate. High temperatures appeared therefore to accelerate pheromone degradation. Third, we assessed the pheromone decay dynamics by a mechanistic model fitted with Bayesian inference. The model predicted ant choice through the evolution of pheromone concentration on trails as a function of both temperature and time since pheromone deposition. Overall, our results highlighted that the effect of high temperatures on recruitment intensity was partly due to pheromone evaporation. In the Mediterranean ant communities, this might affect dominant species relying on chemical recruitment, more than subordinate ant species, less dependent on chemical communication and less sensitive to high temperatures.

  12. Behavioral responses of the diamondback moth, Plutella xylostella, to green leaf volatiles of Brassica oleracea subsp. capitata.

    Science.gov (United States)

    Reddy, G V; Guerrero, A

    2000-12-01

    Green leaf volatiles (GLVs) from Brassica oleracea subsp. capitata L. have been identified as 1-hexanol, (Z)-3-hexen-1-ol, 1-hexen-3-ol, hexanal, (E)-2-hexenal, hexyl acetate, and (Z)-3-hexenyl acetate, by their mass spectra and retention times in comparison with authentic samples. No isothiocyanates were found in the extract. The activity of these chemicals has been determined on mated and unmated males and females of the diamondback moth (DBM) Plutella xylostella in the laboratory (wind tunnel) and in the field. On unmated males, mixtures of (Z)-3-hexenyl acetate, (E)-2-hexenal, and (Z)-3-hexen-1-ol with the pheromone induced attractant/arresting behavior in 80-100% of the males tested, significantly higher than the effect induced by the pheromone alone. On mated males and unmated females the effect of the GLVs alone or in combination with the pheromone was poor, while on mated females these compounds elicited upwind flight and arresting behavior in 40-60% of the females assayed. There was no synergism when these chemicals were mixed with the pheromone. In the field, (Z)-3-hexenyl acetate, the most active GLV in laboratory tests, when mixed with the pheromone in 1:1 ratio, enhanced 6-7-fold the number of females and 20-30% the number of males caught by traps over those baited with the pheromone alone. Our results indicate that the enhancement of the attraction of both males and females of the DBM to traps baited with pheromone blended with the relatively inexpensive and environmentally safe (Z)-3-hexenyl acetate may be important for future control strategies of the pest.

  13. 40 CFR 180.1064 - Tomato pinworm insect pheromone; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Tomato pinworm insect pheromone... RESIDUES IN FOOD Exemptions From Tolerances § 180.1064 Tomato pinworm insect pheromone; exemption from the... residues of both components of the tomato pinworm insect pheromone (E)-4-tridecen-1-yl acetate and (Z)-4...

  14. 40 CFR 180.1124 - Arthropod pheromones; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Arthropod pheromones; exemption from... FOOD Exemptions From Tolerances § 180.1124 Arthropod pheromones; exemption from the requirement of a tolerance. Arthropod pheromones, as described in § 152.25(b) of this chapter, when used in retrievably sized...

  15. Stochastic volatility models and Kelvin waves

    Energy Technology Data Exchange (ETDEWEB)

    Lipton, Alex [Merrill Lynch, Mlfc Main, 2 King Edward Street, London EC1A 1HQ (United Kingdom); Sepp, Artur [Merrill Lynch, 4 World Financial Center, New York, NY 10080 (United States)], E-mail: Alex_Lipton@ml.com, E-mail: Artur_Sepp@ml.com

    2008-08-29

    We use stochastic volatility models to describe the evolution of an asset price, its instantaneous volatility and its realized volatility. In particular, we concentrate on the Stein and Stein model (SSM) (1991) for the stochastic asset volatility and the Heston model (HM) (1993) for the stochastic asset variance. By construction, the volatility is not sign definite in SSM and is non-negative in HM. It is well known that both models produce closed-form expressions for the prices of vanilla option via the Lewis-Lipton formula. However, the numerical pricing of exotic options by means of the finite difference and Monte Carlo methods is much more complex for HM than for SSM. Until now, this complexity was considered to be an acceptable price to pay for ensuring that the asset volatility is non-negative. We argue that having negative stochastic volatility is a psychological rather than financial or mathematical problem, and advocate using SSM rather than HM in most applications. We extend SSM by adding volatility jumps and obtain a closed-form expression for the density of the asset price and its realized volatility. We also show that the current method of choice for solving pricing problems with stochastic volatility (via the affine ansatz for the Fourier-transformed density function) can be traced back to the Kelvin method designed in the 19th century for studying wave motion problems arising in fluid dynamics.

  16. Stochastic volatility models and Kelvin waves

    Science.gov (United States)

    Lipton, Alex; Sepp, Artur

    2008-08-01

    We use stochastic volatility models to describe the evolution of an asset price, its instantaneous volatility and its realized volatility. In particular, we concentrate on the Stein and Stein model (SSM) (1991) for the stochastic asset volatility and the Heston model (HM) (1993) for the stochastic asset variance. By construction, the volatility is not sign definite in SSM and is non-negative in HM. It is well known that both models produce closed-form expressions for the prices of vanilla option via the Lewis-Lipton formula. However, the numerical pricing of exotic options by means of the finite difference and Monte Carlo methods is much more complex for HM than for SSM. Until now, this complexity was considered to be an acceptable price to pay for ensuring that the asset volatility is non-negative. We argue that having negative stochastic volatility is a psychological rather than financial or mathematical problem, and advocate using SSM rather than HM in most applications. We extend SSM by adding volatility jumps and obtain a closed-form expression for the density of the asset price and its realized volatility. We also show that the current method of choice for solving pricing problems with stochastic volatility (via the affine ansatz for the Fourier-transformed density function) can be traced back to the Kelvin method designed in the 19th century for studying wave motion problems arising in fluid dynamics.

  17. Stochastic volatility models and Kelvin waves

    International Nuclear Information System (INIS)

    Lipton, Alex; Sepp, Artur

    2008-01-01

    We use stochastic volatility models to describe the evolution of an asset price, its instantaneous volatility and its realized volatility. In particular, we concentrate on the Stein and Stein model (SSM) (1991) for the stochastic asset volatility and the Heston model (HM) (1993) for the stochastic asset variance. By construction, the volatility is not sign definite in SSM and is non-negative in HM. It is well known that both models produce closed-form expressions for the prices of vanilla option via the Lewis-Lipton formula. However, the numerical pricing of exotic options by means of the finite difference and Monte Carlo methods is much more complex for HM than for SSM. Until now, this complexity was considered to be an acceptable price to pay for ensuring that the asset volatility is non-negative. We argue that having negative stochastic volatility is a psychological rather than financial or mathematical problem, and advocate using SSM rather than HM in most applications. We extend SSM by adding volatility jumps and obtain a closed-form expression for the density of the asset price and its realized volatility. We also show that the current method of choice for solving pricing problems with stochastic volatility (via the affine ansatz for the Fourier-transformed density function) can be traced back to the Kelvin method designed in the 19th century for studying wave motion problems arising in fluid dynamics

  18. De novo analysis of the Adelphocoris suturalis Jakovlev metathoracic scent glands transcriptome and expression patterns of pheromone biosynthesis-related genes.

    Science.gov (United States)

    Luo, Jing; Liu, Xiangyang; Liu, Lang; Zhang, Poyao; Chen, Longjia; Gao, Qiao; Ma, Weihua; Chen, Lizhen; Lei, Chaoliang

    2014-11-10

    Adelphocoris suturalis Jakovlev is a major cotton pest in Southern China. Metathoracic scent glands (MTGs) produced pheromones that play an important role in survival and population propagation of this species, and also show great potential for pest control. Up to the present, there is little information that underlined the molecular basis of the pheromone biosynthesis of this bug. It is essential to clarify genes involved in the production of pheromone components, and also in the regulation of the variation of the blend ratio. We sequenced the transcriptome of metathoracic scent glands (MTGs) of A. suturalis. A total of 52 million 91-bp-long reads were obtained and assembled into 70,296 unigenes with a mean length of 691bp. Of these unigenes, a total of 26,744 (38%) unigenes showed significant similarity to known proteins in the NCBI database (E-valuepheromone biosynthesis were selected, and the gene expression patterns were verified by qRT-PCR. The qRT-PCR results indicated that Asdelta9-DES, AsFAR, AsAOX, Ascarboxylesterase, AsNT-ES and AsATFs have a higher expression level in the period when female A. suturalis release sex pheromones. These data constitutes the first transcriptomic analysis exploring the repertoire of genes expressed in insect MTGs. We identified a large number of potential pheromone biosynthetic pathway genes. In this context, our study provides an invaluable resource for future exploration of molecular mechanisms of pheromone biosynthesis in A. suturalis, as well as other hemipteran species. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Endogenous Lunar Volatiles

    Science.gov (United States)

    McCubbin, F. M.; Liu, Y.; Barnes, J. J.; Boyce, J. W.; Day, J. M. D.; Elardo, S. M.; Hui, H.; Magna, T.; Ni, P.; Tartese, R.; hide

    2017-01-01

    The chapter will begin with an introduction that defines magmatic volatiles (e.g., H, F, Cl, S) versus geochemical volatiles (e.g., K, Rb, Zn). We will discuss our approach of understanding both types of volatiles in lunar samples and lay the ground work for how we will determine the overall volatile budget of the Moon. We will then discuss the importance of endogenous volatiles in shaping the "Newer Views of the Moon", specifically how endogenous volatiles feed forward into processes such as the origin of the Moon, magmatic differentiation, volcanism, and secondary processes during surface and crustal interactions. After the introduction, we will include a re-view/synthesis on the current state of 1) apatite compositions (volatile abundances and isotopic compositions); 2) nominally anhydrous mineral phases (moderately to highly volatile); 3) volatile (moderately to highly volatile) abundances in and isotopic compositions of lunar pyroclastic glass beads; 4) volatile (moderately to highly volatile) abundances in and isotopic compositions of lunar basalts; 5) volatile (moderately to highly volatile) abundances in and isotopic compositions of melt inclusions; and finally 6) experimental constraints on mineral-melt partitioning of moderately to highly volatile elements under lunar conditions. We anticipate that each section will summarize results since 2007 and focus on new results published since the 2015 Am Min review paper on lunar volatiles [9]. The next section will discuss how to use sample abundances of volatiles to understand the source region and potential caveats in estimating source abundances of volatiles. The following section will include our best estimates of volatile abundances and isotopic compositions (where permitted by available data) for each volatile element of interest in a number of important lunar reservoirs, including the crust, mantle, KREEP, and bulk Moon. The final section of the chapter will focus upon future work, outstanding questions

  20. Pheromones cause disease: the exocrinology of anorexia nervosa.

    Science.gov (United States)

    Nicholson, B

    2000-03-01

    The aetiology of anorexia nervosa is exocrinological. This notion is supported by physical evidence in animal models with directly comparable symptomatology. Anorexia nervosa (AN) syndrome would be a puberty delay caused by reception and autoreception of conspecific pheromone emissions: a pheromone-induced puberty delay (PIPD). As such, it would be amenable to medical treatment drawing from forty years of research in animals. This hypothesis is testable. For instance, since food ad libitum is a prerequisite for PIPD, occasional supervised fasting in healthy peripuberal subjects should prevent AN. Besides, tolerating an untestable thought disease (1,2) with symptoms of a curable well-understood animal condition would be anti-scientific and perpetuates medical disaster. Even their endocrinologies are identical. Pheromone feedback tunes animal appetites and immunity to available resources and prospects. In addition to timing puberty, pheromones regulate fertility. Pheromones will probably be implicated in the aetiology of the psychiatric and autoimmune diseases. This is the second in a series of twelve papers to explore this contention systematically. (c) 2000 Harcourt Publishers Ltd Copyright 2000 Harcourt Publishers Ltd.

  1. Sex pheromone and period gene characterization of Lutzomyia longipalpis sensu lato (Lutz & Neiva) (Diptera: Psychodidae) from Posadas, Argentina.

    Science.gov (United States)

    Salomón, Oscar D; Araki, Alejandra S; Hamilton, James Gc; Acardi, Soraya A; Peixoto, Alexandre A

    2010-11-01

    Lutzomyia longipalpis s.l. is the primary vector of Leishmania (L.) infantum in the New World. In this study, male Lutzomyia longipalpis specimens from Posadas, Argentina were characterized for two polymorphic markers: the male sex pheromone and the period (per) gene. The male sex pheromone was identified as (S)-9-methylgermacrene-B, the same compound produced by Lu. longipalpis from Paraguay and many populations from Brazil. The analysis of per gene sequences revealed that the population from Argentina is significantly differentiated from previously studied Brazilian populations. Marker studies could contribute to the understanding of the distribution and spread of urban American visceral leishmaniasis, thus aiding in the design of regional surveillance and control strategies.

  2. The Dynamics of Pheromone Gland Synthesis and Release: a Paradigm Shift for Understanding Sex Pheromone Quantity in Female Moths.

    Science.gov (United States)

    Foster, Stephen P; Anderson, Karin G; Casas, Jérôme

    2018-05-10

    Moths are exemplars of chemical communication, especially with regard to specificity and the minute amounts they use. Yet, little is known about how females manage synthesis and storage of pheromone to maintain release rates attractive to conspecific males and why such small amounts are used. We developed, for the first time, a quantitative model, based on an extensive empirical data set, describing the dynamical relationship among synthesis, storage (titer) and release of pheromone over time in a moth (Heliothis virescens). The model is compartmental, with one major state variable (titer), one time-varying (synthesis), and two constant (catabolism and release) rates. The model was a good fit, suggesting it accounted for the major processes. Overall, we found the relatively small amounts of pheromone stored and released were largely a function of high catabolism rather than a low rate of synthesis. A paradigm shift may be necessary to understand the low amounts released by female moths, away from the small quantities synthesized to the (relatively) large amounts catabolized. Future research on pheromone quantity should focus on structural and physicochemical processes that limit storage and release rate quantities. To our knowledge, this is the first time that pheromone gland function has been modeled for any animal.

  3. Assessment of pheromone production and response in fission yeast by a halo test of induced sporulation

    DEFF Research Database (Denmark)

    Egel, R; Willer, M; Kjaerulff, S

    1994-01-01

    We describe a rapid, sensitive and semi-quantitative plate assay for monitoring pheromone activity in the fission yeast Schizosaccharomyces pombe. It is based on the observation that meiosis requires stimulation by pheromone and exploits diploid strains that will only sporulate after addition...... of exogenous pheromone. The tester strains are heterozygous for mating type, are non-switching, and are mutated in one of the early subfunctions (either mat1-Mc or mat1-Pc), so that meiosis is only induced after exposure to exogenous pheromone (M-factor or P-factor, respectively). Pheromone activity...

  4. Role of polarized G protein signaling in tracking pheromone gradients

    Science.gov (United States)

    McClure, Allison W.; Minakova, Maria; Dyer, Jayme M.; Zyla, Trevin R.; Elston, Timothy C.; Lew, Daniel J.

    2015-01-01

    Summary Yeast cells track gradients of pheromones to locate mating partners. Intuition suggests that uniform distribution of pheromone receptors over the cell surface would yield optimal gradient sensing. However, yeast cells display polarized receptors. The benefit of such polarization was unknown. During gradient tracking, cell growth is directed by a patch of polarity regulators that wanders around the cortex. Patch movement is sensitive to pheromone dose, with wandering reduced on the up-gradient side of the cell, resulting in net growth in that direction. Mathematical modeling suggests that active receptors and associated G proteins lag behind the polarity patch and act as an effective drag on patch movement. In vivo, the polarity patch is trailed by a G protein-rich domain, and this polarized distribution of G proteins is required to constrain patch wandering. Our findings explain why G protein polarization is beneficial, and illuminate a novel mechanism for gradient tracking. PMID:26609960

  5. Sex pheromone receptor proteins. Visualization using a radiolabeled photoaffinity analog

    International Nuclear Information System (INIS)

    Vogt, R.G.; Prestwich, G.D.; Riddiford, L.M.

    1988-01-01

    A tritium-labeled photoaffinity analog of a moth pheromone was used to covalently modify pheromone-selective binding proteins in the antennal sensillum lymph and sensory dendritic membranes of the male silk moth, Antheraea polyphemus. This analog, (E,Z)-6,11-[ 3 H]hexadecadienyl diazoacetate, allowed visualization of a 15-kilodalton soluble protein and a 69-kilodalton membrane protein in fluorescence autoradiograms of electrophoretically separated antennal proteins. Covalent modification of these proteins was specifically reduced when incubation and UV irradiation were conducted in the presence of excess unlabeled pheromone, (E,Z)-6,11-hexadecadienyl acetate. These experiments constitute the first direct evidence for a membrane protein of a chemosensory neuron interacting in a specific fashion with a biologically relevant odorant

  6. Asymmetric Realized Volatility Risk

    Directory of Open Access Journals (Sweden)

    David E. Allen

    2014-06-01

    Full Text Available In this paper, we document that realized variation measures constructed from high-frequency returns reveal a large degree of volatility risk in stock and index returns, where we characterize volatility risk by the extent to which forecasting errors in realized volatility are substantive. Even though returns standardized by ex post quadratic variation measures are nearly Gaussian, this unpredictability brings considerably more uncertainty to the empirically relevant ex ante distribution of returns. Explicitly modeling this volatility risk is fundamental. We propose a dually asymmetric realized volatility model, which incorporates the fact that realized volatility series are systematically more volatile in high volatility periods. Returns in this framework display time varying volatility, skewness and kurtosis. We provide a detailed account of the empirical advantages of the model using data on the S&P 500 index and eight other indexes and stocks.

  7. System of extraction of volatiles from soil using microwave processes

    Science.gov (United States)

    Ethridge, Edwin C. (Inventor); Kaukler, William F. (Inventor)

    2013-01-01

    A device for the extraction and collection of volatiles from soil or planetary regolith. The device utilizes core drilled holes to gain access to underlying volatiles below the surface. Microwave energy beamed into the holes penetrates through the soil or regolith to heat it, and thereby produces vapor by sublimation. The device confines and transports volatiles to a cold trap for collection.

  8. Reactive flash volatilization of fluid fuels

    Science.gov (United States)

    Schmidt, Lanny D.; Dauenhauer, Paul J.; Dreyer, Bradon J.; Salge, James R.

    2013-01-08

    The invention provides methods for the production of synthesis gas. More particularly, various embodiments of the invention relate to systems and methods for volatilizing fluid fuel to produce synthesis gas by using a metal catalyst on a solid support matrix.

  9. Pheromone use for insect control: present status and prospect in Bangladesh

    Directory of Open Access Journals (Sweden)

    Md. Azharul Islam

    2012-06-01

    Full Text Available The insect’s world is filled with many odors. Insects use these odors to cue them in a variety of complex social behaviors, including courtship, mating, and egg laying. Scientists and pest control specialists have known about these complex communication systems for decades. The main aim of this study was to visualize the availability, trends and differences in the sources of pheromone control in agricultural growth of Bangladesh. It also concerned on constrains and present use of pheromone and their possible recommendation on behalf of Bangladesh agriculture. It concentrated on the data during last three decades (1980-2010, comprising status of pheromone use in Bangladesh agriculture and its future. Review revealed that Bangladesh has been enormously successful in increasing pheromone use in agricultural production (especially for vegetables. Understanding of the nature of pheromones and their potential for pest control along with the future prospective of pheromone technique in agriculture were stated. Since the pheromone, technologies for control of major crop pests in Bangladesh are still limited. So that this review emphasized on more attention to the authority to increase the research works and project facilities related to develop and promote pheromone techniques. It is highly recommended to increase availability of pheromone in market, more investment in research and development, introduction of newly identified pheromone for specific pest, to assist government and non-government organizations to work with farmers to reduce harmful insecticide use and promote pheromone tactics as one part of integrated crop management (ICM.

  10. An End-to-End Model of Plant Pheromone Channel for Long Range Molecular Communication.

    Science.gov (United States)

    Unluturk, Bige D; Akyildiz, Ian F

    2017-01-01

    A new track in molecular communication is using pheromones which can scale up the range of diffusion-based communication from μm meters to meters and enable new applications requiring long range. Pheromone communication is the emission of molecules in the air which trigger behavioral or physiological responses in receiving organisms. The objective of this paper is to introduce a new end-to-end model which incorporates pheromone behavior with communication theory for plants. The proposed model includes both the transmission and reception processes as well as the propagation channel. The transmission process is the emission of pheromones from the leaves of plants. The dispersion of pheromones by the flow of wind constitutes the propagation process. The reception process is the sensing of pheromones by the pheromone receptors of plants. The major difference of pheromone communication from other molecular communication techniques is the dispersion channel acting under the laws of turbulent diffusion. In this paper, the pheromone channel is modeled as a Gaussian puff, i.e., a cloud of pheromone released instantaneously from the source whose dispersion follows a Gaussian distribution. Numerical results on the performance of the overall end-to-end pheromone channel in terms of normalized gain and delay are provided.

  11. System of forest insect pheromone communication: stability of «information» molecules to environmental factors

    Directory of Open Access Journals (Sweden)

    V. G. Soukhovolsky

    2016-06-01

    Full Text Available Features of external environmental factors (such as electromagnetic radiation in certain spectral bands influencing pheromone molecules, which are carriers of information for forest insects in the search of the opposite sex, were examined. Stability of pheromone molecules for external influences has been studied for siberian moth Dendrolimus superans sibiricus Tschetv., pine moth Dendrilimus pini L., gypsy moth Lymantria dispar L., for xylophages Ips typographus L., Monochamus urussovi Fish. and Monochamus galloprovincialis Oliv. Properties of pheromone molecules were evaluated by calculations using quantum-chemical method B3LYP. Existing methods of quantum-chemical calculations are useful for analyzing the properties of quite small and uncomplicated molecules of forest insect pheromones. The calculations showed that the molecules of insect pheromones are able to absorb light in the ultraviolet range and move into an excited state. The values of dipole moments, the wavelengths of the absorption, atomic and molecular electronic properties of pheromones in the ground and excited states were calculated. The calculations showed that for the reaction of pheromones with oxygen an energy barrier is somewhat higher than for reactions of pheromones with water vapor. The worst reaction of pheromones with water molecules likely to pheromones such molecules whose dipole moment is comparable to the dipole moment of water. Quantum-chemical characteristics of the pheromone molecules can be linked to specific behavior of the insects.

  12. Two pheromone precursor genes are transcriptionally expressed in the homothallic ascomycete Sordaria macrospora.

    Science.gov (United States)

    Pöggeler, S

    2000-06-01

    In order to analyze the involvement of pheromones in cell recognition and mating in a homothallic fungus, two putative pheromone precursor genes, named ppg1 and ppg2, were isolated from a genomic library of Sordaria macrospora. The ppg1 gene is predicted to encode a precursor pheromone that is processed by a Kex2-like protease to yield a pheromone that is structurally similar to the alpha-factor of the yeast Saccharomyces cerevisiae. The ppg2 gene encodes a 24-amino-acid polypeptide that contains a putative farnesylated and carboxy methylated C-terminal cysteine residue. The sequences of the predicted pheromones display strong structural similarity to those encoded by putative pheromones of heterothallic filamentous ascomycetes. Both genes are expressed during the life cycle of S. macrospora. This is the first description of pheromone precursor genes encoded by a homothallic fungus. Southern-hybridization experiments indicated that ppg1 and ppg2 homologues are also present in other homothallic ascomycetes.

  13. Molecular plant volatile communication.

    Science.gov (United States)

    Holopainen, Jarmo K; Blande, James D

    2012-01-01

    Plants produce a wide array of volatile organic compounds (VOCs) which have multiple functions as internal plant hormones (e.g., ethylene, methyl jasmonate and methyl salicylate), in communication with conspecific and heterospecific plants and in communication with organisms of second (herbivores and pollinators) and third (enemies of herbivores) trophic levels. Species specific VOCs normally repel polyphagous herbivores and those specialised on other plant species, but may attract specialist herbivores and their natural enemies, which use VOCs as host location cues. Attraction of predators and parasitoids by VOCs is considered an evolved indirect defence, whereby plants are able to indirectly reduce biotic stress caused by damaging herbivores. In this chapter we review these interactions where VOCs are known to play a crucial role. We then discuss the importance of volatile communication in self and nonself detection. VOCs are suggested to appear in soil ecosystems where distinction of own roots from neighbours roots is essential to optimise root growth, but limited evidence of above-ground plant self-recognition is available.

  14. Sex Pheromones of C. elegans Males Prime the Female Reproductive System and Ameliorate the Effects of Heat Stress.

    Directory of Open Access Journals (Sweden)

    Erin Z Aprison

    2015-12-01

    Full Text Available Pheromones are secreted molecules that mediate animal communications. These olfactory signals can have substantial effects on physiology and likely play important roles in organismal survival in natural habitats. Here we show that a blend of two ascaroside pheromones produced by C. elegans males primes the female reproductive system in part by improving sperm guidance toward oocytes. Worms have different physiological responses to different ratios of the same two molecules, revealing an efficient mechanism for increasing coding potential of a limited repertoire of molecular signals. The endogenous function of the male sex pheromones has an important side benefit. It substantially ameliorates the detrimental effects of prolonged heat stress on hermaphrodite reproduction because it increases the effectiveness with which surviving gametes are used following stress. Hermaphroditic species are expected to lose female-specific traits in the course of evolution. Our results suggest that some of these traits could have serendipitous utility due to their ability to counter the effects of stress. We propose that this is a general mechanism by which some mating-related functions could be retained in hermaphroditic species, despite their expected decay.

  15. Sex Pheromones of C. elegans Males Prime the Female Reproductive System and Ameliorate the Effects of Heat Stress

    Science.gov (United States)

    Aprison, Erin Z.; Ruvinsky, Ilya

    2015-01-01

    Pheromones are secreted molecules that mediate animal communications. These olfactory signals can have substantial effects on physiology and likely play important roles in organismal survival in natural habitats. Here we show that a blend of two ascaroside pheromones produced by C. elegans males primes the female reproductive system in part by improving sperm guidance toward oocytes. Worms have different physiological responses to different ratios of the same two molecules, revealing an efficient mechanism for increasing coding potential of a limited repertoire of molecular signals. The endogenous function of the male sex pheromones has an important side benefit. It substantially ameliorates the detrimental effects of prolonged heat stress on hermaphrodite reproduction because it increases the effectiveness with which surviving gametes are used following stress. Hermaphroditic species are expected to lose female-specific traits in the course of evolution. Our results suggest that some of these traits could have serendipitous utility due to their ability to counter the effects of stress. We propose that this is a general mechanism by which some mating-related functions could be retained in hermaphroditic species, despite their expected decay. PMID:26645097

  16. Endogenous Lunar Volatiles

    Science.gov (United States)

    McCubbin, F. M.; Liu, Y.; Barnes, J. J.; Anand, M.; Boyce, J. W.; Burney, D.; Day, J. M. D.; Elardo, S. M.; Hui, H.; Klima, R. L.; Magna, T.; Ni, P.; Steenstra, E.; Tartèse, R.; Vander Kaaden, K. E.

    2018-04-01

    This abstract discusses numerous outstanding questions on the topic of endogenous lunar volatiles that will need to be addressed in the coming years. Although substantial insights into endogenous lunar volatiles have been gained, more work remains.

  17. Nonvolatile, semivolatile, or volatile: redefining volatile for volatile organic compounds.

    Science.gov (United States)

    Võ, Uyên-Uyén T; Morris, Michael P

    2014-06-01

    Although widely used in air quality regulatory frameworks, the term "volatile organic compound" (VOC) is poorly defined. Numerous standardized tests are currently used in regulations to determine VOC content (and thus volatility), but in many cases the tests do not agree with each other, nor do they always accurately represent actual evaporation rates under ambient conditions. The parameters (time, temperature, reference material, column polarity, etc.) used in the definitions and the associated test methods were created without a significant evaluation of volatilization characteristics in real world settings. Not only do these differences lead to varying VOC content results, but occasionally they conflict with one another. An ambient evaporation study of selected compounds and a few formulated products was conducted and the results were compared to several current VOC test methodologies: SCAQMD Method 313 (M313), ASTM Standard Test Method E 1868-10 (E1868), and US. EPA Reference Method 24 (M24). The ambient evaporation study showed a definite distinction between nonvolatile, semivolatile, and volatile compounds. Some low vapor pressure (LVP) solvents, currently considered exempt as VOCs by some methods, volatilize at ambient conditions nearly as rapidly as the traditional high-volatility solvents they are meant to replace. Conversely, bio-based and heavy hydrocarbons did not readily volatilize, though they often are calculated as VOCs in some traditional test methods. The study suggests that regulatory standards should be reevaluated to more accurately reflect real-world emission from the use of VOC containing products. The definition of VOC in current test methods may lead to regulations that exclude otherwise viable alternatives or allow substitutions of chemicals that may limit the environmental benefits sought in the regulation. A study was conducted to examine volatility of several compounds and a few formulated products under several current VOC test

  18. Normalization for Implied Volatility

    OpenAIRE

    Fukasawa, Masaaki

    2010-01-01

    We study specific nonlinear transformations of the Black-Scholes implied volatility to show remarkable properties of the volatility surface. Model-free bounds on the implied volatility skew are given. Pricing formulas for the European options which are written in terms of the implied volatility are given. In particular, we prove elegant formulas for the fair strikes of the variance swap and the gamma swap.

  19. Realized Volatility Risk

    NARCIS (Netherlands)

    D.E. Allen (David); M.J. McAleer (Michael); M. Scharth (Marcel)

    2013-01-01

    textabstractIn this paper we document that realized variation measures constructed from highfrequency returns reveal a large degree of volatility risk in stock and index returns, where we characterize volatility risk by the extent to which forecasting errors in realized volatility are substantive.

  20. Codling Moth, Cydia pomonella (L. (Lep.:Tortricidae Control by Mating Disruption Method by Synthetic Pheromones in Khorasan Razavi Province

    Directory of Open Access Journals (Sweden)

    Hashem Kamali

    2017-03-01

    Full Text Available Introduction: Codling moth, Cydia pomonella is one of the key pests of apple in Khorasan Razavi province which annually causes severe fruit damage to apple crop. There are several ways that are used to control and prevent injury to apple products in the world. The most successful and widespread use of pheromones has been in monitoring traps. Mating disruption method by pheromones takes place when enough artificial sources of pheromone are placed in the area that the chance of finding a female by a male is high. Mating, and laying viable eggs is reduced below the point where economically significant damage occurs. Large-scale mating disruption implementation trials have yielded significant reduction in pesticide use while keeping crop damage levels acceptably low. Mating disruption works best if large areas are treated with the pheromones. Currently, chemical control is the most common method of the pest control by using insecticides. In this research, with the goal of eliminating codling moth and minimizing the use of chemical compounds on the apple fruits, the ability of artificial sex pheromones in controlling the codling moth based on mating disruption method was investigated and compared with chemical control in Ghochan County, Khorasan-e-Razavi Province, Iran, in 2013. Materials and Methods: The experiments were conducted in 20 replicates based on a CRB design. The treatments were mating disruption with pheromone dispensers mating disruption + chemical control and chemical control based on the local method. Adult moth was sampled using Delta traps with a sticky insert. 1000 pheromone, which is a two-strand wire rod was produced has been installed on trees per hectare. Pheromones were installed before the first appearance of male moths. 20 to 25 days after each pest generation, randomly 25 fruits were selected and recorded from different directions and heights base on healthy and infected fruits. Results and Discussion: The mating disruption

  1. 75 FR 74044 - Agency Information Collection Activities; Proposed Collection; Comment Request; Gasoline Volatility

    Science.gov (United States)

    2010-11-30

    ...; Gasoline Volatility AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: In compliance... entities: Entities potentially affected by this action are those who produce or import gasoline containing... Additives: Gasoline Volatility, Reporting Requirements for Parties Which Produce of Import Gasoline...

  2. Putative pathway of sex pheromone biosynthesis and degradation by expression patterns of genes identified from female pheromone gland and adult antenna of Sesamia inferens (Walker).

    Science.gov (United States)

    Zhang, Ya-Nan; Xia, Yi-Han; Zhu, Jia-Yao; Li, Sheng-Yun; Dong, Shuang-Lin

    2014-05-01

    The general pathway of biosynthesis and degradation for Type-I sex pheromones in moths is well established, but some genes involved in this pathway remain to be characterized. The purple stem borer, Sesamia inferens, employs a pheromone blend containing components with three different terminal functional groups (Z11-16:OAc, Z11-16:OH, and Z11-16:Ald) of Type-I sex pheromones. Thus, it provides a good model to study the diversity of genes involved in pheromone biosynthesis and degradation pathways. By analyzing previously obtained transcriptomic data of the sex pheromone glands and antennae, we identified 73 novel genes that are possibly related to pheromone biosynthesis (46 genes) or degradation (27 genes). Gene expression patterns and phylogenetic analysis revealed that one desaturase (SinfDes4), one fatty acid reductase (SinfFAR2), and one fatty acid xtransport protein (SinfFATP1) genes were predominantly expressed in pheromone glands, and clustered with genes involved in pheromone synthesis in other moth species. Ten genes including five carboxylesterases (SinfCXE10, 13, 14, 18, and 20), three aldehyde oxidases (SinfAOX1, 2 and 3), and two alcohol dehydrogenases (SinfAD1 and 3) were expressed specifically or predominantly in antennae, and could be candidate genes involved in pheromone degradation. SinfAD1 and 3 are the first reported alcohol dehydrogenase genes with antennae-biased expression. Based on these results we propose a pathway involving these potential enzyme-encoding gene candidates in sex pheromone biosynthesis and degradation in S. inferens. This study provides robust background information for further elucidation of the genetic basis of sex pheromone biosynthesis and degradation, and ultimately provides potential targets to disrupt sexual communication in S. inferens for control purposes.

  3. Novel nanoscale pheromone dispenser for more accurate evaluation of Grapholita molesta (Lepidoptera: Tortricidae) attract-and-kill strategies in the laboratory.

    Science.gov (United States)

    Czarnobai De Jorge, Bruna; Bisotto-de-Oliveira, Ricardo; Pereira, Cláudio Nunes; Sant'Ana, Josué

    2017-09-01

    Nanotechnology has recently allowed the production of formulations for controlled release of active ingredients. In the present study, the electrospinning technique was used to produce nanoscale dispensers for attract-and-kill strategies. Non-woven nanofibres containing insecticide (cypermethrin) and (E)-8,(Z)-8-dodecenyl acetate and (Z)-8-dodecanol (0.87 mg L -1 ), the main components of Grapholita molesta (Lepidoptera: Tortricidae) (Busck) pheromone, were evaluated in laboratory experiments. Male electroantennographic (EAG) responses and mortality (tarsal-contact and attract-and-kill behavioural cages) bioassays were performed for nanofibres (with and without insecticide) exposed for different periods (21, 42, 63 and 84 days) in controlled and non-exposed conditions. There were no significant differences in G. molesta male EAG responses based on the time of exposure within treatments. Nanofibres with pheromone only and with pheromone plus insecticide elicited equal EAG responses. Mortality in tarsal-contact bioassays was greater than 87% after exposure for 84 days. In the attract-and-kill bioassays, mortality ranged from 28.4 to 56.6%, although no difference was observed on insect mortalities over time (24, 48 and 72 h). Incorporation of cypermethrin in nanofibres did not interfere with G. molesta attractiveness. Both aspects of the strategy, the attractant and killing effects, were recorded using innovative nanofibres, and long-term effects suggest a controlled release of pheromone and insecticide. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  4. Use of Mixture Designs to Investigate Contribution of Minor Sex Pheromone Components to Trap Catch of the Carpenterworm Moth, Chilecomadia valdiviana.

    Science.gov (United States)

    Lapointe, Stephen L; Barros-Parada, Wilson; Fuentes-Contreras, Eduardo; Herrera, Heidy; Kinsho, Takeshi; Miyake, Yuki; Niedz, Randall P; Bergmann, Jan

    2017-12-01

    Field experiments were carried out to study responses of male moths of the carpenterworm, Chilecomadia valdiviana (Lepidoptera: Cossidae), a pest of tree and fruit crops in Chile, to five compounds previously identified from the pheromone glands of females. Previously, attraction of males to the major component, (7Z,10Z)-7,10-hexadecadienal, was clearly demonstrated while the role of the minor components was uncertain due to the use of an experimental design that left large portions of the design space unexplored. We used mixture designs to study the potential contributions to trap catch of the four minor pheromone components produced by C. valdiviana. After systematically exploring the design space described by the five pheromone components, we concluded that the major pheromone component alone is responsible for attraction of male moths in this species. The need for appropriate experimental designs to address the problem of assessing responses to mixtures of semiochemicals in chemical ecology is described. We present an analysis of mixture designs and response surface modeling and an explanation of why this approach is superior to commonly used, but statistically inappropriate, designs.

  5. Sex Pheromone Investigation of Anastrepha serpentina (Diptera: Tephritidae)

    Science.gov (United States)

    Attraction of virgin females to odor of calling males was demonstrated. This sex pheromone mediated attraction occurred during the latter half of a 13-h photophase but not during the first half of the day. Two major components of emissions of calling males, 2,5-dimethylpyrazine (DMP) and 2,5-dihyd...

  6. Ovarian steroid sulphate functions as priming pheromone in male ...

    Indian Academy of Sciences (India)

    Unknown

    The study reveals that pre-ovulatory females of the fish Barilius bendelisis (Ham.) release sex steroids and their conjugates into the water and that a steroid sulphate of these compounds functions as a potent sex pheromone which stimulates milt production in conspecific males prior to spawning. Since males exposed to the ...

  7. Development of a pheromone elution rate physical model

    Science.gov (United States)

    M.E. Teske; H.W. Thistle; B.L. Strom; H. Zhu

    2015-01-01

    A first principle modeling approach has been applied to available data describing the elution of semiochemicals from pheromone dispensers. These data included field data for 27 products developed by several manufacturers, including homemade devices, as well as environmental chamber data collected on three semiochemical products. The goal of this effort was to...

  8. Optimization of Pheromone Traps for Coryphodema tristis (Lepidoptera: Cossidae).

    Science.gov (United States)

    Bouwer, Marc Clement; Slippers, Bernard; Wingfield, Michael John; Allison, Jeremy Dean; Rohwer, Egmont Richard

    2017-08-01

    The Coryphodema tristis (Drury) is an important pest of Eucalyptus nitens (Deane and Maiden) plantations in South Africa. The gregarious larvae of this pest cause damage by feeding on the tree sapwood, and adults emerge in spring each year. The aim of this study was to optimize pheromone traps for operational use in management programs. This was achieved by investigating different pheromone blend combinations and trap types for efficacy under field conditions. Our results confirm that the cross vane bucket funnel trap baited with a 95:2.5:2.5 volumetric blend of Z9-14:OAc, Z9-14:OH, and 14Ac was superior to similarly baited standard bucket funnel and delta traps. We also estimated the release rate and ratios of the pheromone compounds loaded into an artificial permeation dispenser through solid-phase microextraction sampling. Results showed that the released blend of pheromone compounds mirrored the dispensed ratios relatively accurately and that release rates are affected by temperature. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. Counter-perfume: using pheromones to prevent female remating.

    Science.gov (United States)

    Malouines, Clara

    2017-08-01

    Strong selection to secure paternity in polyandrous species leads to the evolution of numerous chemicals in the male's seminal content. These include antiaphrodisiac pheromones, which are transmitted from the male to the female during mating to render her unattractive to subsequent males. An increasing number of species have been shown to use these chemicals. Herein, I examine the taxonomic distribution of species using antiaphrodisiac pheromones, the selection pressures driving their evolution in both males and females, and the ecological interactions in which these pheromones are involved. The literature review shows a highly skewed distribution of antiaphrodisiac use; all species currently known to use them are insects with the exception of the garter snakes Thamnophis sirtalis parietalis and T. radix. Nonetheless, many taxa have not yet been tested for the presence of antiaphrodisiacs, in groups both closely and distantly related to species known to express them. Within the Insecta, there have been multiple cases of convergent evolution of antiaphrodisiac pheromones using different chemical compounds and methods of transmission. Antiaphrodisiacs usually benefit males, but their effect on females is variable as they can either prevent them from mating multiple times or help them reduce male harassment when they are unreceptive. Some indirect costs of antiaphrodisiacs also impact both males and females, but more research is needed to determine how general this pattern is. Additional research is also important to understand how antiaphrodisiacs interact with the reproductive biology and sexual communication in different species. © 2016 Cambridge Philosophical Society.

  10. Regulation of Isoprenoid Pheromone Biosynthesis in Bumblebee Males

    Czech Academy of Sciences Publication Activity Database

    Prchalová, Darina; Buček, Aleš; Brabcová, Jana; Žáček, Petr; Kindl, Jiří; Valterová, Irena; Pichová, Iva

    2016-01-01

    Roč. 17, č. 3 (2016), s. 260-267 ISSN 1439-4227 R&D Projects: GA MŠk LO1302; GA ČR GA15-06569S Institutional support: RVO:61388963 Keywords : biosynthesis * Bombus spp. * gene expression * isoprenoid s * pheromones * transcriptional regulation Subject RIV: CE - Biochemistry Impact factor: 2.847, year: 2016

  11. Sensory reception of the primer pheromone ethyl oleate

    Science.gov (United States)

    Muenz, Thomas S.; Maisonnasse, Alban; Plettner, Erika; Le Conte, Yves; Rössler, Wolfgang

    2012-05-01

    Social work force distribution in honeybee colonies critically depends on subtle adjustments of an age-related polyethism. Pheromones play a crucial role in adjusting physiological and behavioral maturation of nurse bees to foragers. In addition to primer effects of brood pheromone and queen mandibular pheromone—both were shown to influence onset of foraging—direct worker-worker interactions influence adult behavioral maturation. These interactions were narrowed down to the primer pheromone ethyl oleate, which is present at high concentrations in foragers, almost absent in young bees and was shown to delay the onset of foraging. Based on chemical analyses, physiological recordings from the antenna (electroantennograms) and the antennal lobe (calcium imaging), and behavioral assays (associative conditioning of the proboscis extension response), we present evidence that ethyl oleate is most abundant on the cuticle, received by olfactory receptors on the antenna, processed in glomeruli of the antennal lobe, and learned in olfactory centers of the brain. The results are highly suggestive that the primer pheromone ethyl oleate is transmitted and perceived between individuals via olfaction at close range.

  12. The evolution of honest queen pheromones in insect societies

    DEFF Research Database (Denmark)

    van Zweden, Jelle Stijn

    2010-01-01

    of their ovaries and by preventing other workers from reproducing (worker policing). However, what maintains the honesty of such queen pheromones is still under discussion. The explanation that an honest queen signal evolves simply because it serves the interest of all colony members does not seem to hold, since...

  13. Shifts in sensory neuron identity parallel differences in pheromone preference in the European corn borer

    Directory of Open Access Journals (Sweden)

    Fotini A Koutroumpa

    2014-10-01

    Full Text Available Pheromone communication relies on highly specific signals sent and received between members of the same species. However, how pheromone specificity is determined in moth olfactory circuits remains unknown. Here we provide the first glimpse into the mechanism that generates this specificity in Ostrinia nubilalis. In Ostrinia nubilalis it was found that a single locus causes strain-specific, diametrically opposed preferences for a 2-component pheromone blend. Previously we found pheromone preference to be correlated with the strain and hybrid-specific relative antennal response to both pheromone components. This led to the current study, in which we detail the underlying mechanism of this differential response, through chemotopically mapping of the pheromone detection circuit in the antenna. We determined that both strains and their hybrids have swapped the neuronal identity of the pheromone-sensitive neurons co-housed within a single sensillum. Furthermore, neurons that mediate behavioral antagonism surprisingly co-express up to five pheromone receptors, mirroring the concordantly broad tuning to heterospecific pheromones. This appears as possible evolutionary adaptation that could prevent cross attraction to a range of heterospecific signals, while keeping the pheromone detection system to its simplest tripartite setup.

  14. Functional Studies of Sex Pheromone Receptors in Asian Corn Borer Ostrinia furnacalis

    Directory of Open Access Journals (Sweden)

    Wei Liu

    2018-05-01

    Full Text Available Lepidopteran insects use sex pheromones for sexual communication. Pheromone receptors expressed on peripheral olfactory receptor neurons (ORNs are critical part to detect the sex pheromones. In genus Ostrinia, several pheromone receptors were functional analyzed in O. nubilalis and O. scapulalis but the knowledge in O. furnacalis was rare. In this study, seven pheromone receptors were deorphanized by heterologous expression system of Xenopus oocytes. Functional types of sensilla trichoidea were classified by single sensillum recordings to interpret the response pattern of olfactory sensory neurons to Ostrinia pheromone components. OfurOR4 and OfurOR6 responded to the major sex pheromone Z/E12-14:OAc. OfurOR4 is the main receptor for both Z/E12-14:OAc and OfurOR6 mainly responded to E12-14:OAc. Functional differentiation of gene duplication were found between OfurOR5a and OfurOR5b. OfurOR5b showed a broad response to most of the pheromone components in O. furnacalis, whereas OfurOR5a was found without ligands. OfurOR7 showed a specific response to Z9-14:OAc and OfurOR8 mainly responded to Z11-14:OAc and E11-14:OAc. OfurOR3 did not respond to any pheromone components. Our results improved the current knowledge of pheromone reception in Ostrinia species which may contribute to speciation.

  15. The role of pheromone receptors for communication and mating in Hypocrea jecorina (Trichoderma reesei)

    Science.gov (United States)

    Seibel, Christian; Tisch, Doris; Kubicek, Christian P.; Schmoll, Monika

    2012-01-01

    Discovery of sexual development in the ascomycete Trichoderma reesei (Hypocrea jecorina) as well as detection of a novel class of peptide pheromone precursors in this fungus indicates promising insights into its physiology and lifestyle. Here we investigated the role of the two pheromone receptors HPR1 and HPR2 in the H. jecorina pheromone-system. We found that these pheromone receptors show an unexpectedly high genetic variability among H. jecorina strains. HPR1 and HPR2 confer female fertility in their cognate mating types (MAT1-1 or MAT1-2, respectively) and mediate induction of fruiting body development. One compatible pheromone precursor–pheromone receptor pair (hpr1–hpp1 or hpr2–ppg1) in mating partners was sufficient for sexual development. Additionally, pheromone receptors were essential for ascospore development, hence indicating their involvement in post-fertilisation events. Neither pheromone precursor genes nor pheromone receptor genes of H. jecorina were transcribed in a strictly mating type dependent manner, but showed enhanced expression levels in the cognate mating type. In the presence of a mating partner under conditions favoring sexual development, transcript levels of pheromone precursors were significantly increased, while those of pheromone receptor genes do not show this trend. In the female sterile T. reesei strain QM6a, transcriptional responses of pheromone precursor and pheromone receptor genes to a mating partner were clearly altered compared to the female fertile wild-type strain CBS999.97. Consequently, a delayed and inappropriate response to the mating partner may be one aspect causing female sterility in QM6a. PMID:22884620

  16. Queen volatiles as a modulator of Tetragonisca angustula drone behavior.

    Science.gov (United States)

    Fierro, Macario M; Cruz-López, Leopoldo; Sánchez, Daniel; Villanueva-Gutiérrez, Rogel; Vandame, Remy

    2011-11-01

    Tetragonisca angustula mating occurs during the virgin queen nuptial flight, usually in the presence of a drone congregation area (DCA). The presence of virgin queen pheromone is considered the trigger for DCA establishment, although this has not been demonstrated experimentally. We established meliponaries, in different habitats, with T. angustula virgin queens during the main drone reproduction period. Eight DCAs were observed in urban areas, and all established outside or near colonies containing at least one virgin queen. The accumulation of drones in the DCAs occurred from 08:00 to 18:00 h and over 3-35 days. The number of drones in DCAs ranged from 60 to 2,000. In field trials, drones were attracted to virgin queens and also, unexpectedly, to physogastric queens. Volatiles collected from both virgin and physogastric queens elicited strong electoantennogram (EAG) responses from drones. Virgin and physogastric queen volatiles were qualitatively similar, but quantitatively different, in chemical composition. The queen's abdomen was the principal source of these compounds. Isopropyl hexanoate (IPH), the most abundant compound in virgin queen volatiles and one of the most abundant in physogastric queen volatiles, was identified as one of the compounds that elicited EAG responses and was demonstrated to attract drones in a field test.

  17. How flies respond to honey bee pheromone: the role of the foraging gene on reproductive response to queen mandibular pheromone

    Science.gov (United States)

    Camiletti, Alison L.; Awde, David N.; Thompson, Graham J.

    2014-01-01

    In this study we test one central prediction from sociogenomic theory—that social and non-social taxa share common genetic toolkits that regulate reproduction in response to environmental cues. We exposed Drosophila females of rover ( for R) and sitter ( for s) genotypes to an ovary-suppressing pheromone derived from the honeybee Apis mellifera. Surprisingly, queen mandibular pheromone (QMP) affected several measures of fitness in flies, and in a manner comparable to the pheromone's normal effect on bee workers. QMP-treated sitter flies had smaller ovaries that contained fewer eggs than did untreated controls. QMP-treated rover flies, by contrast, showed a more variable pattern that only sometimes resulted in ovary inhibition, while a third strain of fly that contains a sitter mutant allele in a rover background ( for s2) showed no ovarian response to QMP. Taken together, our results suggest that distinctly non-social insects have some capacity to respond to social cues, but that this response varies with fly genotype. In general, the interspecific response is consistent with a conserved gene set affecting reproductive physiology. The differential response among strains in particular suggests that for is itself important for modulating the fly's pheromonal response.

  18. Binding interaction between a queen pheromone component HOB and pheromone binding protein ASP1 of Apis cerana.

    Science.gov (United States)

    Weng, Chen; Fu, Yuxia; Jiang, Hongtao; Zhuang, Shulin; Li, Hongliang

    2015-01-01

    The honeybee's social behavior is closely related to the critical response to pheromone, while pheromone binding proteins (PBPs) play an important role in binding and transferring those pheromones. Here we report one known PBP, antennal special protein 1(ASP1), which has high affinity with a queen mandibular pheromone component, methyl-p-hydroxybenzoate (HOB). In this study, multiple fluorescent spectra, UV absorption spectra, circular dichroism (CD) spectra and molecular docking analysis were combined to clarify the binding process. Basically, fluorescence intensity of ASP1 could be considerably quenched by HOB with an appropriate interaction distance (3.1 nm), indicating that a complex, which is more stable in lower temperature, was formed. The fact ΔH < 0, ΔS < 0, by thermodynamic analysis, indicated the van der Waals and hydrogen bond as main driving force. Moreover, synchronous fluorescence spectra and CD spectra analysis showed the change of partial hydrophilicity of ASP1 and the increase of α-helix after HOB addition. In conclusion, ASP1 can strongly and spontaneously interact with HOB. But the binding ability decreases with the rise of temperature, which may be necessary for sufficient social stability of hives. This study provides elucidation of the detailed binding mechanism and potential physicochemical basis of thermal stability to the social behavior of honeybee. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Heritable variation of sex pheromone composition and the potential for evolution of resistance to pheromone-based control of the Indian meal moth, Plodia interpunctella.

    Science.gov (United States)

    Svensson, Glenn P; Ryne, Camilla; Löfstedt, Christer

    2002-07-01

    The short-term evolutionary effect of pheromone-based mating disruption on the mating ability of the Indian meal moth, Plodia interpunctella, was investigated. Three independent selection lines were established, and the mating ability of moths in plastic tents treated with high doses of pheromone and in control tents was compared for two consecutive generations. In addition, the heritability of the sex pheromone blend, measured as the ratio of two major pheromone components (Z,E)-9,12-tetradecadienyl acetate and (Z,E)-9,12-tetradecadienol, was estimated. Based on a mother-daughter regression analysis including 21 families, the heritability of the pheromone blend was 0.65 +/- 0.14, indicating a potential for evolutionary change of the character. However, no increase in mating ability of females in pheromone-treated tents or alteration of the pheromone blend was observed in any selection line when compared with control lines, indicating no or weak selection on the pheromone blend as well as other traits influencing mating ability of this species under the created mating disruption conditions. Factors contributing to the lack of selection effects are discussed.

  20. Involvement of the G-protein-coupled dopamine/ecdysteroid receptor DopEcR in the behavioral response to sex pheromone in an insect.

    Directory of Open Access Journals (Sweden)

    Antoine Abrieux

    Full Text Available Most animals including insects rely on olfaction to find their mating partners. In moths, males are attracted by female-produced sex pheromones inducing stereotyped sexual behavior. The behaviorally relevant olfactory information is processed in the primary olfactory centre, the antennal lobe (AL. Evidence is now accumulating that modulation of sex-linked behavioral output occurs through neuronal plasticity via the action of hormones and/or catecholamines. A G-protein-coupled receptor (GPCR binding to 20-hydroxyecdysone, the main insect steroid hormone, and dopamine, has been identified in Drosophila (DmDopEcR, and was suggested to modulate neuronal signaling. In the male moth Agrotis ipsilon, the behavioral and central nervous responses to pheromone are age-dependent. To further unveil the mechanisms of this olfactory plasticity, we searched for DopEcR and tested its potential role in the behavioral response to sex pheromone in A. ipsilon males. Our results show that A. ipsilon DopEcR (named AipsDopEcR is predominantly expressed in the nervous system. The corresponding protein was detected immunohistochemically in the ALs and higher brain centers including the mushroom bodies. Moreover, AipsDopEcR expression increased with age. Using a strategy of RNA interference, we also show that silencing of AipsDopEcR inhibited the behavioral response to sex pheromone in wind tunnel experiments. Altogether our results indicate that this GPCR is involved in the expression of sexual behavior in the male moth, probably by modulating the central nervous processing of sex pheromone through the action of one or both of its ligands.

  1. Kinetic properties of a sex pheromone-degrading enzyme: the sensillar esterase of Antheraea polyphemus.

    OpenAIRE

    Vogt, R G; Riddiford, L M; Prestwich, G D

    1985-01-01

    Behavioral and electrophysiological evidence has suggested that sex pheromone is rapidly inactivated within the sensory hairs soon after initiation of the action-potential spike. We report the isolation and characterization of a sex-pheromone-degrading enzyme from the sensory hairs of the silkmoth Antheraea polyphemus. In the presence of this enzyme at physiological concentration, the pheromone [(6E,11Z)-hexadecadienyl acetate] has an estimated half-life of 15 msec. Our findings suggest a mol...

  2. REDUCING THE THREAT TO CONTROL INVASIVE SIGNAL CRAYFISH REDUCING: THE POTENTIAL USE OF PHEROMONES

    Directory of Open Access Journals (Sweden)

    STEBBING P. D.

    2003-04-01

    Full Text Available The need for an effective method of controlling invasive species of crayfish is of utmost importance given the plight of Europe’s native crayfish species. Many techniques have been applied to the growing problem with little success. Pheromones have been used to control terrestrial insect pests for a number of years with many success stories. The concept of applying pheromone control methods to the aquatic environment is by no means new, but has not been previously developed. This paper discusses the preliminary results from field trials testing traps baited with Pacifastacus leniusculus pheromones, and the potential application of the pheromones in controlling P. leniusculus populations.

  3. Healthy Adult Male Facial Skin Surface Lipid Pheromone p.o. to Treat Opioid Addiction

    Science.gov (United States)

    2018-03-20

    Opioid Addiction; Opioid Abuse, Continuous Use; Opioid Use; Opioid-Related Disorders; Paternal Pheromone Deficiency; Opioid Dependence; Opioid Abuse; Opioid-use Disorder; Opioid Intoxication; Opioid Abuse, Episodic

  4. Pheromone modulates two phenotypically plastic traits - adult reproduction and larval diapause - in the nematode Caenorhabditis elegans.

    Science.gov (United States)

    Wharam, Barney; Weldon, Laura; Viney, Mark

    2017-08-22

    Animals use information from their environment to make decisions, ultimately to maximize their fitness. The nematode C. elegans has a pheromone signalling system, which hitherto has principally been thought to be used by worms in deciding whether or not to arrest their development as larvae. Recent studies have suggested that this pheromone can have other roles in the C. elegans life cycle. Here we demonstrate a new role for the C. elegans pheromone, showing that it accelerates hermaphrodites' reproductive rate, a phenomenon which we call pheromone-dependent reproductive plasticity (PDRP). We also find that pheromone accelerates larval growth rates, but this depends on a live bacterial food source, while PDRP does not. Different C. elegans strains all show PDRP, though the magnitude of these effects differ among the strains, which is analogous to the diversity of arrested larval phenotypes that this pheromone also induces. Using a selection experiment we also show that selection for PDRP or for larval arrest affects both the target and the non-target trait, suggesting that there is cross-talk between these two pheromone-dependent traits. Together, these results show that C. elegans' pheromone is a signal that acts at two key life cycle points, controlling alternative larval fates and affecting adult hermaphrodites' reproduction. More broadly, these results suggest that to properly understand and interpret the biology of pheromone signalling in C. elegans and other nematodes, the life-history biology of these organisms in their natural environment needs to be considered.

  5. Functional specificity of sex pheromone receptors in the cotton bollworm Helicoverpa armigera.

    Directory of Open Access Journals (Sweden)

    Yang Liu

    Full Text Available Male moths can accurately perceive the sex pheromone emitted from conspecific females by their highly accurate and specific olfactory sensory system. Pheromone receptors are of special importance in moth pheromone reception because of their central role in chemosensory signal transduction processes that occur in olfactory receptor neurons in the male antennae. There are a number of pheromone receptor genes have been cloned, however, only a few have been functionally characterized. Here we cloned six full-length pheromone receptor genes from Helicoverpa armigera male antennae. Real-time PCR showing all genes exhibited male-biased expression in adult antennae. Functional analyses of the six pheromone receptor genes were then conducted in the heterologous expression system of Xenopus oocytes. HarmOR13 was found to be a specific receptor for the major sex pheromone component Z11-16:Ald. HarmOR6 was equally tuned to both of Z9-16: Ald and Z9-14: Ald. HarmOR16 was sensitively tuned to Z11-16: OH. HarmOR11, HarmOR14 and HarmOR15 failed to respond to the tested candidate pheromone compounds. Our experiments elucidated the functions of some pheromone receptor genes of H. armigera. These advances may provide remarkable evidence for intraspecific mating choice and speciation extension in moths at molecular level.

  6. Sexy DEG/ENaC channels involved in gustatory detection of fruit fly pheromones.

    Science.gov (United States)

    Pikielny, Claudio W

    2012-11-06

    Hydrocarbon pheromones on the cuticle of Drosophila melanogaster modulate the complex courtship behavior of males. Recently, three members of the degenerin/epithelial Na+ channel (DEG/ENaC) family of sodium channel subunits, Ppk25, Ppk23, and Ppk29 (also known as Nope), have been shown to function in gustatory perception of courtship-modulating contact pheromones. All three proteins are required for the activation of male courtship by female pheromones. Specific interactions between two of them have been demonstrated in cultured cells, suggesting that, in a subset of cells where they are coexpressed, these three subunits function within a common heterotrimeric DEG/ENaC channel. Such a DEG/ENaC channel may be gated by pheromones, either directly or indirectly, or alternatively may control the excitability of pheromone-sensing cells. In addition, these studies identify taste neurons that respond specifically to courtship-modulating pheromones and mediate their effects on male behavior. Two types of pheromone-sensing taste neurons, F and M cells, have been defined on the basis of their specific response to either female or male pheromones. These reports set the stage for the dissection of the molecular and cellular mechanisms that mediate gustatory detection of contact pheromones.

  7. Volatility in Equilibrium

    DEFF Research Database (Denmark)

    Bollerslev, Tim; Sizova, Natalia; Tauchen, George

    Stock market volatility clusters in time, carries a risk premium, is fractionally inte- grated, and exhibits asymmetric leverage effects relative to returns. This paper develops a first internally consistent equilibrium based explanation for these longstanding empirical facts. The model is cast i......, and the dynamic cross-correlations of the volatility measures with the returns calculated from actual high-frequency intra-day data on the S&P 500 aggregate market and VIX volatility indexes....

  8. Synergy of aggregation pheromone with methyl (E,E,Z)-2,4,6-decatrienoate in attraction of brown marmorated stink bug, Halyomorpha halys

    Science.gov (United States)

    The male-produced aggregation pheromone of the brown marmorated stink bug ((BMSB), Halyomorpha halys (Stål) (Hemiptera: Pentatomidae)), recently identified as a mixture of (3S,6S,7R,10S)-10,11-epoxy-1-bisabolen-3-ol and (3S,6S,7R,10R)-10,11-epoxy-1-bisabolen-3-ol, offers new opportunities for manage...

  9. Chemical compounds of the foraging recruitment pheromone in bumblebees

    Science.gov (United States)

    Granero, Angeles Mena; Sanz, José M. Guerra; Gonzalez, Francisco J. Egea; Vidal, José L. Martinez; Dornhaus, Anna; Ghani, Junaid; Serrano, Ana Roldán; Chittka, Lars

    2005-08-01

    When the frenzied and irregular food-recruitment dances of bumblebees were first discovered, it was thought that they might represent an evolutionary prototype to the honeybee waggle dance. It later emerged that the primary function of the bumblebee dance was the distribution of an alerting pheromone. Here, we identify the chemical compounds of the bumblebee recruitment pheromone and their behaviour effects. The presence of two monoterpenes and one sesquiterpene (eucalyptol, ocimene and farnesol) in the nest airspace and in the tergal glands increases strongly during foraging. Of these, eucalyptol has the strongest recruitment effect when a bee nest is experimentally exposed to it. Since honeybees use terpenes for marking food sources rather than recruiting foragers inside the nest, this suggests independent evolutionary roots of food recruitment in these two groups of bees.

  10. Enzymatic oxidations of alcohols in biosynthesis of bumblebee pheromones

    OpenAIRE

    Bártová, Adéla

    2016-01-01

    Secretion of cephalic labial gland of Buff-tailed bumblebee males (Bombus terrestris) contains a mixture of terpene alcohols, aliphatic alcohols, esters and alkanes with small amount of aldehydes potentially biosynthetized of (S)-2,3-dihydrofarnesol and geranylcitronellol (major alcoholic compounds). This secretion acts as a marking and luring pheromone during patrolling. This study is focused on oxidation of terpene alcohols using enzymes of cephalic labial gland of a bumblebee. In vitro inc...

  11. Volatile constituents of Trichothecium roseum.

    Science.gov (United States)

    Vanhaelen, M; Vanhaelen-Fastre, R; Geeraerts, J

    1978-06-01

    In the course of investigation of Trichothecium roseum (Fungi Imperfecti) for its attractancy against Tyrophagus putrescentiae (cheese mite), the twenty following volatile compounds produced at a very low concentration by the microfungus were identified by gc, gc/ms, gc/c.i.ms and tlc: 3-methyl-1-butanol, 3-octanone, 1-octen-3-one, 3-octanol, octa-1,5-dien-3 one, 1-octen-3-ol, 6-methyl-5-hepten-2-ol, octa-1,5-dien-3 ol, furfural, linalool, linalyl acetate, terpineol (alpha and beta) citronellyl acetate, nerol, citronellol, phenylacetaldehyde, benzyl alcohol geranyl acetate, 1-phenyl ethanol and nerolidol. Octa-1,5-dien-3-ol and octa-1,5-dien-3-one have not been previously isolated from fungi; octa-1,5-dien-3-ol is the most potent attractant amount the volatile compounds detected by gc.

  12. A Single Sex Pheromone Receptor Determines Chemical Response Specificity of Sexual Behavior in the Silkmoth Bombyx mori

    OpenAIRE

    Sakurai, Takeshi; Mitsuno, Hidefumi; Haupt, Stephan Shuichi; Uchino, Keiro; Yokohari, Fumio; Nishioka, Takaaki; Kobayashi, Isao; Sezutsu, Hideki; Tamura, Toshiki; Kanzaki, Ryohei

    2011-01-01

    In insects and other animals, intraspecific communication between individuals of the opposite sex is mediated in part by chemical signals called sex pheromones. In most moth species, male moths rely heavily on species-specific sex pheromones emitted by female moths to identify and orient towards an appropriate mating partner among a large number of sympatric insect species. The silkmoth, Bombyx mori, utilizes the simplest possible pheromone system, in which a single pheromone component, (E, Z...

  13. Genetic Control of Conventional and Pheromone-Stimulated Biofilm Formation in Candida albicans

    Science.gov (United States)

    Lin, Ching-Hsuan; Kabrawala, Shail; Fox, Emily P.; Nobile, Clarissa J.; Johnson, Alexander D.; Bennett, Richard J.

    2013-01-01

    Candida albicans can stochastically switch between two phenotypes, white and opaque. Opaque cells are the sexually competent form of C. albicans and therefore undergo efficient polarized growth and mating in the presence of pheromone. In contrast, white cells cannot mate, but are induced – under a specialized set of conditions – to form biofilms in response to pheromone. In this work, we compare the genetic regulation of such “pheromone-stimulated” biofilms with that of “conventional” C. albicans biofilms. In particular, we examined a network of six transcriptional regulators (Bcr1, Brg1, Efg1, Tec1, Ndt80, and Rob1) that mediate conventional biofilm formation for their potential roles in pheromone-stimulated biofilm formation. We show that four of the six transcription factors (Bcr1, Brg1, Rob1, and Tec1) promote formation of both conventional and pheromone-stimulated biofilms, indicating they play general roles in cell cohesion and biofilm development. In addition, we identify the master transcriptional regulator of pheromone-stimulated biofilms as C. albicans Cph1, ortholog of Saccharomyces cerevisiae Ste12. Cph1 regulates mating in C. albicans opaque cells, and here we show that Cph1 is also essential for pheromone-stimulated biofilm formation in white cells. In contrast, Cph1 is dispensable for the formation of conventional biofilms. The regulation of pheromone- stimulated biofilm formation was further investigated by transcriptional profiling and genetic analyses. These studies identified 196 genes that are induced by pheromone signaling during biofilm formation. One of these genes, HGC1, is shown to be required for both conventional and pheromone-stimulated biofilm formation. Taken together, these observations compare and contrast the regulation of conventional and pheromone-stimulated biofilm formation in C. albicans, and demonstrate that Cph1 is required for the latter, but not the former. PMID:23637598

  14. Understanding Financial Market Volatility

    NARCIS (Netherlands)

    A. Opschoor (Anne)

    2014-01-01

    markdownabstract__Abstract__ Volatility has been one of the most active and successful areas of research in time series econometrics and economic forecasting in recent decades. Loosely speaking, volatility is defined as the average magnitude of fluctuations observed in some phenomenon over

  15. Improving Garch Volatility Forecasts

    NARCIS (Netherlands)

    Klaassen, F.J.G.M.

    1998-01-01

    Many researchers use GARCH models to generate volatility forecasts. We show, however, that such forecasts are too variable. To correct for this, we extend the GARCH model by distinguishing two regimes with different volatility levels. GARCH effects are allowed within each regime, so that our model

  16. Asymmetric Realized Volatility Risk

    NARCIS (Netherlands)

    D.E. Allen (David); M.J. McAleer (Michael); M. Scharth (Marcel)

    2014-01-01

    markdownabstract__Abstract__ In this paper we document that realized variation measures constructed from high-frequency returns reveal a large degree of volatility risk in stock and index returns, where we characterize volatility risk by the extent to which forecasting errors in realized

  17. Effect of pheromone induction on transfer of the Enterococcus faecalis plasmid pCF10 in intestinal mucus ex vivo

    DEFF Research Database (Denmark)

    Licht, Tine Rask; Hammerum, Anette Marie; Jensen, Lars Bogø

    2001-01-01

    The effect of synthetic sex pheromone on pheromone-inducible conjugation between the isogenic Enterococcus faecalis strains OG1RF and OG1SS was investigated in (i) Todd-Hewitt broth medium and (ii) intestinal mucus isolated from germ-free rats. In broth, the presence of synthetic pheromone cCF10...

  18. Effects of two pheromone trap densities against banana weevil Cosmopolites sordidus, populations and their impact on plant damage in Uganda

    NARCIS (Netherlands)

    Tinzaara, W.; Gold, C.S.; Kagezi, G.H.; Dicke, M.; Huis, van A.; Nankinga, C.; Tushemereirwe, W.; Ragama, P.E.

    2005-01-01

    An on-farm study to evaluate the effect of pheromone trap density on the population of the banana weevil, Cosmopolites sordidus (Germar) (Col., Curculionidae) was conducted in Masaka district, Uganda. The pheromone used was Cosmolure+, a commercially available weevil aggregation pheromone. Forty-two

  19. Genes involved in sex pheromone biosynthesis of Ephestia cautella, an important food storage pest, are determined by transcriptome sequencing

    KAUST Repository

    Antony, Binu; Soffan, Alan; Jakše, Jernej; Alfaifi, Sulieman; Sutanto, Koko D.; Aldosari, Saleh A.; Aldawood, Abdulrahman S.; Pain, Arnab

    2015-01-01

    Our study provides important background information on the enzymes involved in pheromone biosynthesis. This information will be useful for the in vitro production of E. cautella sex pheromones and may provide potential targets for disrupting the pheromone-based communication system of E. cautella to prevent infestations.

  20. Re-evaluation of the PBAN receptor molecule: characterization of PBANR variants expressed in the pheromone glands of moths

    Science.gov (United States)

    Sex pheromone production in most moths is initiated following pheromone biosynthesis activating neuropeptide receptor (PBANR) activation. PBANR was initially cloned from pheromone glands (PGs) of Helicoverpa zea and Bombyx mori. The B. mori PBANR is characterized by a relatively long C-terminus that...

  1. The volatility of HOL

    International Nuclear Information System (INIS)

    Wren, D.J.; Sanipelli, G.

    1985-01-01

    The volatility of HOI has been measured using a mass spectrometer to analyze the gas phase above an aqueous solution. The HOI in solution was generated continuously in a flow reactor that combined I/sup -/ and OCl/sup -/ solutions. The analysis has resulted in a lower limit of 6X10/sup 3/ mol . dm/sup -3/ . atm/sup -1/ for the equilibrium constant for the reaction HOI(g)/equilibrium/HOI(aq). This value is a factor 30 greater than the best previous estimate. This new limit for HOI volatility results in higher total iodine partition coefficients, particularly for solutions with pH>8. The upper limit for the equilibrium constant is consistent with essentially zero volatility for HOI. The effect of HOI volatility on total iodine volatility is briefly discussed as a function of solution chemistry and kinetics

  2. Flower volatiles, crop varieties and bee responses.

    Directory of Open Access Journals (Sweden)

    Björn K Klatt

    Full Text Available Pollination contributes to an estimated one third of global food production, through both the improvement of the yield and the quality of crops. Volatile compounds emitted by crop flowers mediate plant-pollinator interactions, but differences between crop varieties are still little explored. We investigated whether the visitation of crop flowers is determined by variety-specific flower volatiles using strawberry varieties (Fragaria x ananassa Duchesne and how this affects the pollination services of the wild bee Osmia bicornis L. Flower volatile compounds of three strawberry varieties were measured via headspace collection. Gas chromatography showed that the three strawberry varieties produced the same volatile compounds but with quantitative differences of the total amount of volatiles and between distinct compounds. Electroantennographic recordings showed that inexperienced females of Osmia bicornis had higher antennal responses to all volatile compounds than to controls of air and paraffin oil, however responses differed between compounds. The variety Sonata was found to emit a total higher level of volatiles and also higher levels of most of the compounds that evoked antennal responses compared with the other varieties Honeoye and Darselect. Sonata also received more flower visits from Osmia bicornis females under field conditions, compared with Honeoye. Our results suggest that differences in the emission of flower volatile compounds among strawberry varieties mediate their attractiveness to females of Osmia bicornis. Since quality and quantity of marketable fruits depend on optimal pollination, a better understanding of the role of flower volatiles in crop production is required and should be considered more closely in crop-variety breeding.

  3. Geometric isomers of sex pheromone components do not affect attractancy of Conopomorpha cramerella in cocoa plantations

    Science.gov (United States)

    Sex pheromone of cocoa pod borer (CPB), Conopomorpha cramerella, has previously been identified as a blend of (E,Z,Z)- and (E,E,Z)-4,6,10-hexadecatrienyl acetates and the corresponding alcohols. These pheromone components have been synthesized with modification of the existing method and relative at...

  4. Recent development in insect pheromone research, in particular in the Netherlands

    NARCIS (Netherlands)

    Ritter, F.J.; Persoons, C.J.

    1975-01-01

    A review is given of recent pheromone work carried out in the Netherlands on Lepidoptera, cockroaches, pharaoh's ants and termites, special emphasis being given to isolation and identification aspects. The sex pheromones of three leaf roller moths (Tortricidae) have been isolated, identified and

  5. Sex pheromones of the southern armyworm moth: isolation, identification, and synthesis.

    Science.gov (United States)

    Jacobson, M; Redfern, R E; Jones, W A; Aldridge, M H

    1970-10-30

    Two sex pheromones have been isolated from the female southern armyworm moth, Prodenia eridania (Cramer), and identified as cis-9-tetradecen-1-ol acetate, identical with the sex pheromone of the fall armyworm moth, Spodoptera frugiperda (J. E. Smith), and cis-9,trans-12-tetradecadien-1-ol acetate.

  6. Pheromone-modulated behavioral suites influence colony growth in the honey bee (Apis mellifera)

    Science.gov (United States)

    Pankiw, Tanya; Roman, Roman; Sagili, Ramesh R.; Zhu-Salzman, Keyan

    2004-12-01

    The success of a species depends on its ability to assess its environment and to decide accordingly which behaviors are most appropriate. Many animal species, from bacteria to mammals, are able to communicate using interspecies chemicals called pheromones. In addition to exerting physiological effects on individuals, for social species, pheromones communicate group social structure. Communication of social structure is important to social insects for the allocation of its working members into coordinated suites of behaviors. We tested effects of long-term treatment with brood pheromone on suites of honey bee brood rearing and foraging behaviors. Pheromone-treated colonies reared significantly greater brood areas and more adults than controls, while amounts of stored pollen and honey remained statistically similar. Brood pheromone increased the number of pollen foragers and the pollen load weights they returned. It appeared that the pheromone-induced increase in pollen intake was directly canalized into more brood rearing. A two-way pheromone priming effect was observed, such that some workers from the same age cohorts showed an increased and extended capacity to rear larvae, while others were recruited at significantly younger ages into pollen-specific foraging. Brood pheromone affected suites of nursing and foraging behaviors allocating worker and pollen resources associated with an important fitness trait, colony growth.

  7. The ras1 function of Schizosaccharomyces pombe mediates pheromone-induced transcription

    DEFF Research Database (Denmark)

    Nielsen, O; Davey, William John; Egel, R

    1992-01-01

    Loss of ras1+ function renders fission yeast cells unable to undergo morphological changes in response to mating pheromones, whereas cells carrying activated mutations in ras1 are hyper-responsive. This has led to the suggestion that the ras1 gene product plays a role in mating pheromone signal...

  8. Alarm pheromone does not modulate 22-kHz calls in male rats.

    Science.gov (United States)

    Muyama, Hiromi; Kiyokawa, Yasushi; Inagaki, Hideaki; Takeuchi, Yukari; Mori, Yuji

    2016-03-15

    Rats are known to emit a series of ultrasonic vocalizations, termed 22-kHz calls, when exposed to distressing stimuli. Pharmacological studies have indicated that anxiety mediates 22-kHz calls in distressed rats. We previously found that exposure to the rat alarm pheromone increases anxiety in rats. Therefore, we hypothesized that the alarm pheromone would increase 22-kHz calls in pheromone-exposed rats. Accordingly, we tested whether exposure to the alarm pheromone induced 22-kHz calls, as well as whether the alarm pheromone increased 22-kHz calls in response to an aversive conditioned stimulus (CS). Rats were first fear-conditioned to an auditory and contextual CS. On the following day, the rats were either exposed to the alarm pheromone or a control odor that was released from the neck region of odor-donor rats. Then, the rats were re-exposed to the aversive CS. The alarm pheromone neither induced 22-kHz calls nor increased 22-kHz calls in response to the aversive CS. In contrast, the control odor unexpectedly reduced the total number and duration of 22-kHz calls elicited by the aversive CS, as well as the duration of freezing. These results suggest that the alarm pheromone does not affect 22-kHz calls in rats. However, we may have found evidence for an appeasing olfactory signal, released from the neck region of odor-donor rats. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Effects of aggregation pheromone on individual behaviour and food web interactions: a field study on Drosophila

    NARCIS (Netherlands)

    Wertheim, B.; Allemand, R.; Vet, L.E.M.; Dicke, M.

    2006-01-01

    The effects of an aggregation pheromone on individual behaviour and food web interactions were investigated in two ecological communities, using Drosophila melanogaster and D. simulans as focal species. 2. Fruit substrates with aggregation pheromone were significantly more attractive to adult D.

  10. Stochasticity in the enterococcal sex pheromone response revealed by quantitative analysis of transcription in single cells.

    Science.gov (United States)

    Breuer, Rebecca J; Bandyopadhyay, Arpan; O'Brien, Sofie A; Barnes, Aaron M T; Hunter, Ryan C; Hu, Wei-Shou; Dunny, Gary M

    2017-07-01

    In Enterococcus faecalis, sex pheromone-mediated transfer of antibiotic resistance plasmids can occur under unfavorable conditions, for example, when inducing pheromone concentrations are low and inhibiting pheromone concentrations are high. To better understand this paradox, we adapted fluorescence in situ hybridization chain reaction (HCR) methodology for simultaneous quantification of multiple E. faecalis transcripts at the single cell level. We present direct evidence for variability in the minimum period, maximum response level, and duration of response of individual cells to a specific inducing condition. Tracking of induction patterns of single cells temporally using a fluorescent reporter supported HCR findings. It also revealed subpopulations of rapid responders, even under low inducing pheromone concentrations where the overall response of the entire population was slow. The strong, rapid induction of small numbers of cells in cultures exposed to low pheromone concentrations is in agreement with predictions of a stochastic model of the enterococcal pheromone response. The previously documented complex regulatory circuitry controlling the pheromone response likely contributes to stochastic variation in this system. In addition to increasing our basic understanding of the biology of a horizontal gene transfer system regulated by cell-cell signaling, demonstration of the stochastic nature of the pheromone response also impacts any future efforts to develop therapeutic agents targeting the system. Quantitative single cell analysis using HCR also has great potential to elucidate important bacterial regulatory mechanisms not previously amenable to study at the single cell level, and to accelerate the pace of functional genomic studies.

  11. Effects of aggregation pheromone on individual behaviour and food web interactions : A field study on Drosophila

    NARCIS (Netherlands)

    Wertheim, Bregje; Allemand, Roland; Vet, Louise E. M.; Dicke, Marcel

    1. The effects of an aggregation pheromone on individual behaviour and food web interactions were investigated in two ecological communities, using Drosophila melanogaster and D. simulatis as focal species. 2. Fruit substrates with aggregation pheromone were significantly more attractive to adult D.

  12. Gonadotropin-Releasing Hormone Modulates Vomeronasal Neuron Response to Male Salamander Pheromone

    Directory of Open Access Journals (Sweden)

    Celeste R. Wirsig-Wiechmann

    2012-01-01

    Full Text Available Electrophysiological studies have shown that gonadotropin-releasing hormone (GnRH modifies chemosensory neurons responses to odors. We have previously demonstrated that male Plethodon shermani pheromone stimulates vomeronasal neurons in the female conspecific. In the present study we used agmatine uptake as a relative measure of the effects of GnRH on this pheromone-induced neural activation of vomeronasal neurons. Whole male pheromone extract containing 3 millimolar agmatine with or without 10 micromolar GnRH was applied to the nasolabial groove of female salamanders for 45 minutes. Immunocytochemical procedures were conducted to visualize and quantify relative agmatine uptake as measured by labeling density of activated vomeronasal neurons. The relative number of labeled neurons did not differ between the two groups: pheromone alone or pheromone-GnRH. However, vomeronasal neurons exposed to pheromone-GnRH collectively demonstrated higher labeling intensity, as a percentage above background (75% as compared with neurons exposed to pheromone alone (63%, P < 0.018. Since the labeling intensity of agmatine within neurons signifies the relative activity levels of the neurons, these results suggest that GnRH increases the response of female vomeronasal neurons to male pheromone.

  13. Proteinaceous Pheromone Homologs Identified from the Cloacal Gland Transcriptome of a Male Axolotl, Ambystoma mexicanum.

    Directory of Open Access Journals (Sweden)

    Kevin W Hall

    Full Text Available Pheromones play an important role in modifying vertebrate behavior, especially during courtship and mating. Courtship behavior in urodele amphibians often includes female exposure to secretions from the cloacal gland, as well as other scent glands. The first vertebrate proteinaceous pheromone discovered, the decapeptide sodefrin, is a female attracting pheromone secreted by the cloacal gland of male Cynops pyrrhogaster. Other proteinaceous pheromones in salamanders have been shown to elicit responses from females towards conspecific males. The presence and levels of expression of proteinaceous pheromones have not been identified in the family Ambystomatidae, which includes several important research models. The objective of this research was therefore to identify putative proteinaceous pheromones from male axolotls, Ambystoma mexicanum, as well as their relative expression levels. The results indicate that axolotls possess two different forms of sodefrin precursor-like factor (alpha and beta, as well as a putative ortholog of plethodontid modulating factor. The beta form of sodefrin precursor-like factor was amongst the most highly expressed transcripts within the cloacal gland. The ortholog of plethodontid modulating factor was expressed at a level equivalent to the beta sodefrin precursor-like factor. The results are from a single male axolotl; therefore, we are unable to assess how representative our results may be. Nevertheless, the presence of these highly expressed proteinaceous pheromones suggests that male axolotls use multiple chemical cues to attract female conspecifics. Behavioral assays would indicate whether the putative protein pheromones elicit courtship activity from female axolotls.

  14. Proteinaceous Pheromone Homologs Identified from the Cloacal Gland Transcriptome of a Male Axolotl, Ambystoma mexicanum.

    Science.gov (United States)

    Hall, Kevin W; Eisthen, Heather L; Williams, Barry L

    2016-01-01

    Pheromones play an important role in modifying vertebrate behavior, especially during courtship and mating. Courtship behavior in urodele amphibians often includes female exposure to secretions from the cloacal gland, as well as other scent glands. The first vertebrate proteinaceous pheromone discovered, the decapeptide sodefrin, is a female attracting pheromone secreted by the cloacal gland of male Cynops pyrrhogaster. Other proteinaceous pheromones in salamanders have been shown to elicit responses from females towards conspecific males. The presence and levels of expression of proteinaceous pheromones have not been identified in the family Ambystomatidae, which includes several important research models. The objective of this research was therefore to identify putative proteinaceous pheromones from male axolotls, Ambystoma mexicanum, as well as their relative expression levels. The results indicate that axolotls possess two different forms of sodefrin precursor-like factor (alpha and beta), as well as a putative ortholog of plethodontid modulating factor. The beta form of sodefrin precursor-like factor was amongst the most highly expressed transcripts within the cloacal gland. The ortholog of plethodontid modulating factor was expressed at a level equivalent to the beta sodefrin precursor-like factor. The results are from a single male axolotl; therefore, we are unable to assess how representative our results may be. Nevertheless, the presence of these highly expressed proteinaceous pheromones suggests that male axolotls use multiple chemical cues to attract female conspecifics. Behavioral assays would indicate whether the putative protein pheromones elicit courtship activity from female axolotls.

  15. Investigating a novel pathway by which pheromone-based mating disruption may protect crops

    Science.gov (United States)

    Pheromone-based mating disruption has been a successful, relatively new technology that growers use to reduce key insect populations. Mating disruption systems function by sending out false plumes of the insect sex pheromones – this interferes with the insect’s ability to find a mate, preempting egg...

  16. Structure elucidation of some insect pheromones : a contribution to the development of selective pest control agents

    NARCIS (Netherlands)

    Persoons, C.J.

    1977-01-01

    The use of pheromones is one of the methods currently being investigated intensively as an alternative method of insect control. The various ways in which pheromones might be used in insect control programmes are briefly discussed in Chapter 1.

    Chapter 2 gives a detailed description of the

  17. Pheromone-mediated aggregation in nonsocial arthropods: an evolutionary ecological perspective

    NARCIS (Netherlands)

    Wertheim, B.; van Baalen, E-J.A.; Dicke, M.; Vet, L.E.M.

    2005-01-01

    Although the use of aggregation pheromones has been reported for hundreds of nonsocial arthropod species, the evolutionary ecological aspects of this behavior have received little attention. Despite the elaborate literature on mechanisms, robust data on costs and benefits of aggregation pheromones

  18. Genetic dissection of pheromone processing reveals main olfactory system-mediated social behaviors in mice.

    Science.gov (United States)

    Matsuo, Tomohiko; Hattori, Tatsuya; Asaba, Akari; Inoue, Naokazu; Kanomata, Nobuhiro; Kikusui, Takefumi; Kobayakawa, Reiko; Kobayakawa, Ko

    2015-01-20

    Most mammals have two major olfactory subsystems: the main olfactory system (MOS) and vomeronasal system (VNS). It is now widely accepted that the range of pheromones that control social behaviors are processed by both the VNS and the MOS. However, the functional contributions of each subsystem in social behavior remain unclear. To genetically dissociate the MOS and VNS functions, we established two conditional knockout mouse lines that led to either loss-of-function in the entire MOS or in the dorsal MOS. Mice with whole-MOS loss-of-function displayed severe defects in active sniffing and poor survival through the neonatal period. In contrast, when loss-of-function was confined to the dorsal MOB, sniffing behavior, pheromone recognition, and VNS activity were maintained. However, defects in a wide spectrum of social behaviors were observed: attraction to female urine and the accompanying ultrasonic vocalizations, chemoinvestigatory preference, aggression, maternal behaviors, and risk-assessment behaviors in response to an alarm pheromone. Functional dissociation of pheromone detection and pheromonal induction of behaviors showed the anterior olfactory nucleus (AON)-regulated social behaviors downstream from the MOS. Lesion analysis and neural activation mapping showed pheromonal activation in multiple amygdaloid and hypothalamic nuclei, important regions for the expression of social behavior, was dependent on MOS and AON functions. Identification of the MOS-AON-mediated pheromone pathway may provide insights into pheromone signaling in animals that do not possess a functional VNS, including humans.

  19. Male scent-marking pheromone of Bombus ardens ardens (Hymenoptera; Apidae) attracts both conspecific queens and males

    Science.gov (United States)

    Kubo, Ryohei; Harano, Ken-ichi; Ono, Masato

    2017-10-01

    To explore the role of the volatiles emitted from male labial gland (LG) of the bumblebee Bombus ardens ardens, we investigated the responses of virgin queens and males to volatiles using a gas chromatography-electroantennographic detector (GC-EAD) system and Y-tube olfactometer. GC-EAD analysis revealed that citronellol, the main compound detected in the male LG, caused clear electrophysiological responses in the antennae of B. a. ardens virgin queens and males although two minor compounds elicited antennal responses when applied in a high concentration. Behavioral tests using a Y-tube olfactometer showed that queens and males were significantly attracted to both LG extracts and citronellol more than to the solvent alone. This is the first study to demonstrate that citronellol as a major compound of male scent-marking pheromone in B. a. ardens functions as a sex attractant for queens. The results also suggest that this compound has another function as a trail marker used by males.

  20. North American Invasion of the Tawny Crazy Ant (Nylanderia fulva) Is Enabled by Pheromonal Synergism from Two Separate Glands.

    Science.gov (United States)

    Zhang, Qing-He; McDonald, Danny L; Hoover, Doreen R; Aldrich, Jeffrey R; Schneidmiller, Rodney G

    2015-09-01

    A new invader, the "tawny crazy ant", Nylanderia fulva (Hymenoptera: Formicidae; Formicinae), is displacing the red imported fire ant, Solenopsis invicta (Formicidae: Myrmicinae), in the southern U.S., likely through its superior chemical arsenal and communication. Alone, formic acid is unattractive, but this venom (= poison) acid powerfully synergizes attraction of tawny crazy ants to volatiles from the Dufour's gland secretion of N. fulva workers, including the two major components, undecane and 2-tridecanone. The unexpected pheromonal synergism between the Dufour's gland and the venom gland appears to be another key factor, in addition to previously known defensive and detoxification semiochemical features, for the successful invasion and domination of N. fulva in the southern U.S. This synergism is an efficient mechanism enabling N. fulva workers to outcompete Solenopsis and other ant species for food and territory. From a practical standpoint, judicious point-source release formulation of tawny crazy ant volatiles may be pivotal for enhanced attract-and-kill management of this pest.

  1. Interior Volatile Reservoirs in Mercury

    Science.gov (United States)

    Anzures, B. A.; Parman, S. W.; Milliken, R. E.; Head, J. W.

    2018-05-01

    More measurements of 1) surface volatiles, and 2) pyroclastic deposits paired with experimental volatile analyses in silicate minerals can constrain conditions of melting and subsequent eruption on Mercury.

  2. Forecasting volatility for options valuation

    International Nuclear Information System (INIS)

    Belaifa, M.; Morimune, K.

    2006-01-01

    The petroleum sector plays a neuralgic role in the basement of world economies, and market actors (producers, intermediates, as well as consumers) are continuously subjected to the dynamics of unstable oil market. Huge amounts are being invested along the production chain to make one barrel of crude oil available to the end user. Adding to that are the effect of geopolitical dynamics as well as geological risks as expressed in terms of low chances of successful discoveries. In addition, fiscal regimes and regulations, technology and environmental concerns are also among some of the major factors that contribute to the substantial risk in the oil industry and render the market structure vulnerable to crises. The management of these vulnerabilities require modern tools to reduce risk to a certain level, which unfortunately is a non-zero value. The aim of this paper is, therefore, to provide a modern technique to capture the oil price stochastic volatility that can be implemented to value the exposure of an investor, a company, a corporate or a Government. The paper first analyses the regional dependence on oil prices, through a historical perspective and then looks at the evolution of pricing environment since the large price jumps of the 1970s. The main causes of oil prices volatility are treated in the third part of the paper. The rest of the article deals with volatility models and forecasts used in risk management, with an implication for pricing derivatives. (author)

  3. Pheromone Binding Protein EhipPBP1 Is Highly Enriched in the Male Antennae of the Seabuckthorn Carpenterworm and Is Binding to Sex Pheromone Components

    Directory of Open Access Journals (Sweden)

    Ping Hu

    2018-04-01

    Full Text Available The seabuckthorn carpenterworm moth Eogystia hippophaecolus is a major threat to seabuckthorn plantations, causing considerable ecological and economic losses in China. Transcriptomic analysis of E. hippophaecolus previously identified 137 olfactory proteins, including three pheromone-binding proteins (PBPs. We investigated the function of E. hippophaecolus PBP1 by studying its mRNA and protein expression profiles and its binding ability with different compounds. The highest levels of expression were in the antennae, particularly in males, with much lower levels of expression in the legs and external genitals. Recombinant PBP1 showed strong binding to sex-pheromone components, suggesting that antennal EhipPBP1 is involved in binding sex-pheromone components during pheromone communication.

  4. Pluto's Volatile Transport

    Science.gov (United States)

    Young, Leslie

    2012-10-01

    Pluto's varying subsolar latitude and heliocentric distance leads to large variations in the surface volatile distribution and surface pressure. I present results of new volatile transport models (Young 2012a, b). The models include insolation, thermal emission, subsurface conduction, heating of a volatile slab, internal heat flux, latent heat of sublimation, and strict global mass balance. Numeric advances include initial conditions that allow for rapid convergence, efficient computation with matrix arithmetic, and stable Crank-Nicholson timesteps for both bare and volatile-covered areas. Runs of the model show six distinct seasons on Pluto. (1) As Pluto approaches perihelion, the volatiles on the old winter pole (the Rotational North Pole, RNP) becomes more directly illuminated , and the pressure and albedo rise rapidly. (2) When a new ice cap forms on the Rotational South Pole, RSP, volatiles are exchanged between poles. The pressure and albedo change more slowly. (3) When all volatiles have sublimed from the RNP, the albedo and pressure drop rapidly. (4-6) A similar pattern is repeated near aphelion with a reversal of the roles and the poles. I will compare results with earlier Pluto models of Hansen and Paige (1996), show the dependence on parameters such as substrate inertia, and make predictions for the New Horizons flyby of Pluto in 2015. This work was supported, in part, by funding from NASA Planetary Atmospheres Grant NNG06GF32G and the Spitzer project (JPL research support Agreement 1368573). Hansen, C. J. and D. A. Paige 1996. Seasonal Nitrogen Cycles on Pluto. Icarus 120, 247-265. Young, L. A. 2012a. Volatile transport on inhomogeneous surfaces: I - Analytic expressions, with application to Pluto’s day. Icarus, in press Young, L. A. 2012b. Volatile transport on inhomogeneous surfaces: II. Numerical calculations, with application to Pluto's season. In preparation.

  5. Identification of receptors of main sex-pheromone components of three Lepidopteran species.

    Science.gov (United States)

    Mitsuno, Hidefumi; Sakurai, Takeshi; Murai, Masatoshi; Yasuda, Tetsuya; Kugimiya, Soichi; Ozawa, Rika; Toyohara, Haruhiko; Takabayashi, Junji; Miyoshi, Hideto; Nishioka, Takaaki

    2008-09-01

    Male moths discriminate conspecific female-emitted sex pheromones. Although the chemical components of sex pheromones have been identified in more than 500 moth species, only three components in Bombyx mori and Heliothis virescens have had their receptors identified. Here we report the identification of receptors for the main sex-pheromone components in three moth species, Plutella xylostella, Mythimna separata and Diaphania indica. We cloned putative sex-pheromone receptor genes PxOR1, MsOR1 and DiOR1 from P. xylostella, M. separata and D. indica, respectively. Each of the three genes was exclusively expressed with an Or83b orthologous gene in male olfactory receptor neurons (ORNs) that are surrounded by supporting cells expressing pheromone-binding-protein (PBP) genes. By two-electrode voltage-clamp recording, we tested the ligand specificity of Xenopus oocytes co-expressing PxOR1, MsOR1 or DiOR1 with an OR83b family protein. Among the seven sex-pheromone components of the three moth species, the oocytes dose-dependently responded only to the main sex-pheromone component of the corresponding moth species. In our study, PBPs were not essential for ligand specificity of the receptors. On the phylogenetic tree of insect olfactory receptors, the six sex-pheromone receptors identified in the present and previous studies are grouped in the same subfamily but have no relation with the taxonomy of moths. It is most likely that sex-pheromone receptors have randomly evolved from ancestral sex-pheromone receptors before the speciation of moths and that their ligand specificity was modified by mutations of local amino acid sequences after speciation.

  6. Identifying Possible Pheromones of Cerambycid Beetles by Field Testing Known Pheromone Components in Four Widely Separated Regions of the United States.

    Science.gov (United States)

    Millar, Jocelyn G; Mitchell, Robert F; Mongold-Diers, Judith A; Zou, Yunfan; Bográn, Carlos E; Fierke, Melissa K; Ginzel, Matthew D; Johnson, Crawford W; Meeker, James R; Poland, Therese M; Ragenovich, Iral; Hanks, Lawrence M

    2018-02-09

    The pheromone components of many cerambycid beetles appear to be broadly shared among related species, including species native to different regions of the world. This apparent conservation of pheromone structures within the family suggests that field trials of common pheromone components could be used as a means of attracting multiple species, which then could be targeted for full identification of their pheromones. Here, we describe the results of such field trials that were conducted in nine states in the northeastern, midwestern, southern, and western United States. Traps captured 12,742 cerambycid beetles of 153 species and subspecies. Species attracted in significant numbers to a particular treatment (some in multiple regions) included 19 species in the subfamily Cerambycinae, 15 species in the Lamiinae, one species in the Prioninae, and two species in the Spondylidinae. Pheromones or likely pheromones for many of these species, such as 3-hydroxyhexan-2-one and syn- and anti-2,3-hexanediols for cerambycine species, and fuscumol and/or fuscumol acetate for lamiine species, had already been identified. New information about attractants (in most cases likely pheromone components) was found for five cerambycine species (Ancylocera bicolor [Olivier], Elaphidion mucronatum [Say], Knulliana cincta cincta [Drury], Phymatodes aeneus LeConte, and Rusticoclytus annosus emotus [Brown]), and five lamiine species (Ecyrus dasycerus dasycerus [Say], Lepturges symmetricus [Haldeman], Sternidius misellus [LeConte], Styloleptus biustus biustus [LeConte], and Urgleptes signatus [LeConte]). Consistent attraction of some species to the same compounds in independent bioassays demonstrated the utility and reliability of pheromone-based methods for sampling cerambycid populations across broad spatial scales. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Modeling the cellular mechanisms and olfactory input underlying the triphasic response of moth pheromone-sensitive projection neurons.

    Directory of Open Access Journals (Sweden)

    Yuqiao Gu

    Full Text Available In the antennal lobe of the noctuid moth Agrotis ipsilon, most pheromone-sensitive projection neurons (PNs exhibit a triphasic firing pattern of excitation (E1-inhibition (I-excitation (E2 in response to a pulse of the sex pheromone. To understand the mechanisms underlying this stereotypical discharge, we developed a biophysical model of a PN receiving inputs from olfactory receptor neurons (ORNs via nicotinic cholinergic synapses. The ORN is modeled as an inhomogeneous Poisson process whose firing rate is a function of time and is fitted to extracellular data recorded in response to pheromone stimulations at various concentrations and durations. The PN model is based on the Hodgkin-Huxley formalism with realistic ionic currents whose parameters were derived from previous studies. Simulations revealed that the inhibitory phase I can be produced by a SK current (Ca2+-gated small conductance K+ current and that the excitatory phase E2 can result from the long-lasting response of the ORNs. Parameter analysis further revealed that the ending time of E1 depends on some parameters of SK, Ca2+, nACh and Na+ currents; I duration mainly depends on the time constant of intracellular Ca2+ dynamics, conductance of Ca2+ currents and some parameters of nACh currents; The mean firing frequency of E1 and E2 depends differentially on the interaction of various currents. Thus it is likely that the interplay between PN intrinsic currents and feedforward synaptic currents are sufficient to generate the triphasic firing patterns observed in the noctuid moth A. ipsilon.

  8. RNA interference of pheromone biosynthesis-activating neuropeptide receptor suppresses mating behavior by inhibiting sex pheromone production in Plutella xylostella (L.).

    Science.gov (United States)

    Lee, Dae-Weon; Shrestha, Sony; Kim, A Young; Park, Seok Joo; Yang, Chang Yeol; Kim, Yonggyun; Koh, Young Ho

    2011-04-01

    Sex pheromone production is regulated by pheromone biosynthesis-activating neuropeptide (PBAN) in many lepidopteran species. We cloned a PBAN receptor (Plx-PBANr) gene from the female pheromone gland of the diamondback moth, Plutella xylostella (L.). Plx-PBANr encodes 338 amino acids and has conserved structural motifs implicating in promoting G protein coupling and tyrosine-based sorting signaling along with seven transmembrane domains, indicating a typical G protein-coupled receptor. The expression of Plx-PBANr was found only in the pheromone gland of female adults among examined tissues and developmental stages. Heterologous expression in human uterus cervical cancer cells revealed that Plx-PBANr induced significant calcium elevation when challenged with Plx-PBAN. Female P. xylostella injected with double-stranded RNA specific to Plx-PBANr showed suppression of the receptor gene expression and exhibited significant reduction in pheromone biosynthesis, which resulted in loss of male attractiveness. Taken together, the identified PBAN receptor is functional in PBAN signaling via calcium secondary messenger, which leads to activation of pheromone biosynthesis and male attraction. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Volatile flavor compounds in yogurt: a review.

    Science.gov (United States)

    Cheng, Hefa

    2010-11-01

    Considerable knowledge has been accumulated on the volatile compounds contributing to the aroma and flavor of yogurt. This review outlines the production of the major flavor compounds in yogurt fermentation and the analysis techniques, both instrumental and sensory, for quantifying the volatile compounds in yogurt. The volatile compounds that have been identified in plain yogurt are summarized, with the few key aroma compounds described in detail. Most flavor compounds in yogurt are produced from lipolysis of milkfat and microbiological transformations of lactose and citrate. More than 100 volatiles, including carbonyl compounds, alcohols, acids, esters, hydrocarbons, aromatic compounds, sulfur-containing compounds, and heterocyclic compounds, are found in yogurt at low to trace concentrations. Besides lactic acid, acetaldehyde, diacetyl, acetoin, acetone, and 2-butanone contribute most to the typical aroma and flavor of yogurt. Extended storage of yogurt causes off-flavor development, which is mainly attributed to the production of undesired aldehydes and fatty acids during lipid oxidation. Further work on studying the volatile flavor compounds-matrix interactions, flavor release mechanisms, and the synergistic effect of flavor compounds, and on correlating the sensory properties of yogurt with the compositions of volatile flavor compounds are needed to fully elucidate yogurt aroma and flavor.

  10. Analysis of volatiles from irradiated yeast extract

    International Nuclear Information System (INIS)

    Liao Tao; Li Xin; Zu Xiaoyan; Chen Yuxia; Geng Shengrong

    2013-01-01

    The method for determination volatiles from irradiated yeast extract (YE) using headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) was developed in this paper. The extraction conditions were optimized with reference to the peak area and number of volatiles as aldehyde, ketone, alcohol, acid, ester and sulfur compounds. The optimized conditions of HS-SPME for volatiles in irradiated YE were: divinyl benzene/Carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber, extration time 40 min, extraction temperature 40℃. The volatiles from YE irradiated by 0-19.8 kGy were detected using HS-SPME coupled with GC-MS. The results showed that only 15 volatiles were detected from no irradiated YE and main compounds were acetic acid, 2, 3-butanediol and 1-hexanol, 2-ethyl-. There were 40 volatiles detected from irradiated YE and the main compounds were acetic acid, phenylethyl alcohol, heptanal and nonanal. Compare to no irradiated yeast extract, the aldehyde, ketone, alkene and disulfide, dimethyl were produced by irradiating process. (authors)

  11. Volatilization of iodine from soils and plants

    International Nuclear Information System (INIS)

    Wildung, R.E.; Cataldo, D.A.; Garland, T.R.

    1985-04-01

    Elevated levels of 129 I, a long-lived fission product, are present in the environment as a result of nuclear weapons testing and fuel reprocessing. To aid in understanding the anomalous behavior of this element, relative to natural I ( 127 I), in the vicinity of nuclear fuel reprocessing plants, preliminary laboratory-growth chamber studies were undertaken to examine the possible formation of volatile inorganic and organic I species in soil and plant systems. Inorganic 129 I added to soil was volatilized from both the soil and plant during plant growth, at average ratios of 2 x 10 -3 %/day soil and 9 x 10 -3 %/day foliage, respectively. Volatilization rates from soil were an order of magnitude less in the absence of growing roots. Less than 2% of soil or plant volatiles was subsequently retained by plant canopies. Volatile I, chemically characterized by selective sorption methods, consisted principally of alkyl iodides formed by both soil and plant processes. However, plants and soils containing actively growing roots produced a larger fraction of volatile inorganic I than soil alone. 14 refs., 1 fig., 3 tabs

  12. A reference gene set for sex pheromone biosynthesis and degradation genes from the diamondback moth, Plutella xylostella, based on genome and transcriptome digital gene expression analyses

    OpenAIRE

    He, Peng; Zhang, Yun-Fei; Hong, Duan-Yang; Wang, Jun; Wang, Xing-Liang; Zuo, Ling-Hua; Tang, Xian-Fu; Xu, Wei-Ming; He, Ming

    2017-01-01

    Background Female moths synthesize species-specific sex pheromone components and release them to attract male moths, which depend on precise sex pheromone chemosensory system to locate females. Two types of genes involved in the sex pheromone biosynthesis and degradation pathways play essential roles in this important moth behavior. To understand the function of genes in the sex pheromone pathway, this study investigated the genome-wide and digital gene expression of sex pheromone biosynthesi...

  13. Field evaluation of potential pheromone lures for Lygus lineolaris (Hemiptera: Miridae) in the Mid-South

    Science.gov (United States)

    Plant bugs (Hemiptera: Miridae) are phytophagous pests of cultivated plants around the world. In the mid-South region of the United States, Lygus lineolaris is a primary pest of cotton, and causes economic damage. Previously published research about the volatiles produced by members of the genus Lyg...

  14. Non-volatile memories

    CERN Document Server

    Lacaze, Pierre-Camille

    2014-01-01

    Written for scientists, researchers, and engineers, Non-volatile Memories describes the recent research and implementations in relation to the design of a new generation of non-volatile electronic memories. The objective is to replace existing memories (DRAM, SRAM, EEPROM, Flash, etc.) with a universal memory model likely to reach better performances than the current types of memory: extremely high commutation speeds, high implantation densities and retention time of information of about ten years.

  15. The Economic Value of Predicting Stock Index Returns and Volatility

    NARCIS (Netherlands)

    Marquering, W.; Verbeek, M.J.C.M.

    2000-01-01

    In this paper, we analyze the economic value of predicting index returns as well as volatility. On the basis of fairly simple linear models, estimated recursively, we produce genuine out-of-sample forecasts for the return on the S&P 500 index and its volatility. Using monthly data from 1954-1998, we

  16. American options under stochastic volatility

    NARCIS (Netherlands)

    Chockalingam, A.; Muthuraman, K.

    2011-01-01

    The problem of pricing an American option written on an underlying asset with constant price volatility has been studied extensively in literature. Real-world data, however, demonstrate that volatility is not constant, and stochastic volatility models are used to account for dynamic volatility

  17. Are queen ants inhibited by their own pheromone?

    DEFF Research Database (Denmark)

    Holman, L.; Leroy, C.; Jørgensen, Charlotte

    2013-01-01

    . Communication in social insects is predominantly chemical, and the mechanisms regulating processes such as reproductive division of labor are becoming increasingly well understood. Recently, a queen cuticular hydrocarbon (3-MeC31) that inhibits worker reproduction and aggression was isolated in the ant Lasius...... niger. Here, we find that this pheromone also has a weak negative effect on queen productivity and oogenesis. Because 3-MeC31 is present on both queens and their brood, we suggest that it is used by ants of both castes to adjust their fecundity to the amount of developing brood and the presence of other...

  18. Regulation of glycoprotein synthesis in yeast by mating pheromones

    International Nuclear Information System (INIS)

    Tanner, W.

    1984-01-01

    In Saccharomyces cerevisiae, glycosylated proteins amount to less than 2% of the cell protein. Two intensively studied examples of yeast glycoproteins are the external cell wall - associated invertase and the vacuolar carboxypeptidase Y. Recently, it was shown that the mating pheromone, alpha factor, specifically and strongly inhibits the synthesis of N-glycosylated proteins in haploid a cells, whereas O-glycosylated proteins are not affected. In this paper, the pathways of glycoprotein biosynthesis are summarized briefly, and evidence is presented that mating pheomones have a regulatory function in glycoprotein synthesis

  19. Principal volatil components of Txakoli of Bizkaia

    Directory of Open Access Journals (Sweden)

    Ana Escobal

    1995-12-01

    Full Text Available The aim of this work was to characterize the Txakoli of Bizkaia, a wine produced in the Basque Country. This note gives account of the volatile content of the wine which has been awarded by the Denominacíon de Origen Bizkaiko Txakolina quality label (BOPV, 1994.

  20. Factors influencing capture of invasive sea lamprey in traps baited with a synthesized sex pheromone component

    Science.gov (United States)

    Johnson, Nicholas; Siefkes, Michael J.; Wagner, C. Michael; Bravener, Gale; Steeves, Todd; Twohey, Michael; Li, Weiming

    2015-01-01

    The sea lamprey, Petromyzon marinus, is emerging as a model organism for understanding how pheromones can be used for manipulating vertebrate behavior in an integrated pest management program. In a previous study, a synthetic sex pheromone component 7α,12α, 24-trihydroxy-5α-cholan-3-one 24-sulfate (3kPZS) was applied to sea lamprey traps in eight streams at a final in-stream concentration of 10−12 M. Application of 3kPZS increased sea lamprey catch, but where and when 3kPZS had the greatest impact was not determined. Here, by applying 3kPZS to additional streams, we determined that overall increases in yearly exploitation rate (proportion of sea lampreys that were marked, released, and subsequently recaptured) were highest (20–40 %) in wide streams (~40 m) with low adult sea lamprey abundance (pheromone), sea lamprey may have been more responsive to a partial sex pheromone blend emitted from traps. Furthermore, we found that the largest and most consistent responses to 3kPZS were during nights early in the trapping season, when water temperatures were increasing. This may have occurred because, during periods of increasing water temperatures, sea lamprey become more active and males at large may not have begun to release sex pheromone. In general, our results are consistent with those for pheromones of invertebrates, which are most effective when pest density is low and when pheromone competition is low.

  1. Cloning and functional characterization of three new pheromone receptors from the diamondback moth, Plutella xylostella.

    Science.gov (United States)

    Liu, Yipeng; Liu, Yang; Jiang, Xingchuan; Wang, Guirong

    The highly specialized olfactory receptor neurons (ORNs) on the antennae of male moths can recognize blends of several pheromone components. In previous studies, a total of six candidate pheromone receptor (PR) genes were cloned and functionally characterized in the diamondback moth, Plutella xylostella. In the present work, we report on three novel candidate pheromone receptor genes: PxylOR8, PxylOR41, and PxylOR45 in the same species. Gene expression analysis revealed that PxylOR8 is specifically expressed in female adult antennae, while PxylOR41 and PxylOR45 are expressed in antennae in both sexes, but with a male bias. In situ hybridization revealed that PxylOR8, PxylOR41 and PxylOR45 are localized in long trichoid sensilla. Functional analyses on the three pheromone receptor genes were then performed using the heterologous expression system of Xenopus oocytes. PxylOR41 was tuned to two minor pheromone components Z9-14:Ac, Z9-14:OH, and their analog Z9-14:Ald. PxylOR8 and PxylOR45 did not respond to any tested pheromone components and analogs. These results may contribute to clarifying how pheromone detection works in P. xylostella. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Demonstration and Characterization of a Persistent Pheromone Lure for the Navel Orangeworm, Amyelois transitella (Lepidoptera: Pyralidae

    Directory of Open Access Journals (Sweden)

    Bradley S. Higbee

    2014-07-01

    Full Text Available The lack of an effective pheromone lure has made it difficult to monitor and manage the navel orangeworm, Amyelois transitella (Lepidoptera: Pyralidae, in the economically important crops in which it is the primary insect pest. A series of experiments was conducted to demonstrate and characterize a practical synthetic pheromone lure for capturing navel orangeworm males. Traps baited with lures prepared with 1 or 2 mg of a three- or four-component formulation captured similar numbers of males. The fluctuation over time in the number of males captured in traps baited with the pheromone lure correlated significantly with males captured in female-baited traps. Traps baited with the pheromone lure usually did not capture as many males as traps baited with unmated females, and the ratio of males trapped with pheromone to males trapped with females varied between crops and with abundance. The pheromone lure described improves the ability of pest managers to detect and monitor navel orangeworm efficiently and may improve management and decrease insecticide treatments applied as a precaution against damage. Awareness of differences between male interaction with the pheromone lure and calling females, as shown in these data, will be important as further studies and experience determine how best to use this lure for pest management.

  3. Modeling of pheromone communication system of forest Lepidopterous insects. II. Model of female searching by male

    Directory of Open Access Journals (Sweden)

    A. V. Kovalev

    2015-06-01

    Full Text Available We propose an agent­based simulation model search. This model allows us to evaluate the effectiveness of different males­females pheromone search strategies for Lepidoptera. In the model, we consider the simplest case of the search, when the pheromone has only one chemical component. It is assumed that the insects are able to detect the pheromone molecules and the sensory cells generate action potentials in contact with the pheromone for some time. Thereafter pheromone molecule is inactivated. This behavior can be regarded as a memory of individual. Proportion of individuals who have reached the source is selected as an integral indicator of the search efficiency. To evaluate the effectiveness, numeric experiments were performed in different conditions: random walk, search algorithm without memory, and algorithm with memory and return mechanism. The resulting effectiveness of source localization by insects for flight in turbulent flows is ~ 70 %, which corresponds to experiments with live specimens in literature. In this case, proposed pheromone search algorithm is quite simple, which makes it biologically correct. Conducted modeling calculations can be the starting point for planning of field observations and pest monitoring systems using pheromone traps.

  4. A simple, cost-effective emitter for controlled release of fish pheromones: development, testing, and application to management of the invasive sea lamprey

    Science.gov (United States)

    Wagner, Michael C.; Hanson, James E.; Meckley, Trevor D.; Johnson, Nicholas; Bals, Jason D.

    2018-01-01

    Semiochemicals that elicit species-specific attraction or repulsion have proven useful in the management of terrestrial pests and hold considerable promise for control of nuisance aquatic species, particularly invasive fishes. Because aquatic ecosystems are typically large and open, use of a semiochemical to control a spatially dispersed invader will require the development of a cost-effective emitter that is easy to produce, environmentally benign, inexpensive, and controls the release of the semiochemical without altering its structure. We examined the release properties of five polymers, and chose polyethylene glycol (PEG) as the best alternative. In a series of laboratory and field experiments, we examined the response of the invasive sea lamprey to PEG, and to a partial sex pheromone emitted from PEG that has proven effective as a trap bait to capture migrating sea lamprey prior to spawning. Our findings confirm that the sea lamprey does not behaviorally respond to PEG, and that the attractant response to the pheromone component was conserved when emitted from PEG. Further, we deployed the pheromone-PEG emitters as trap bait during typical control operations in three Great Lakes tributaries, observing similar improvements in trap performance when compared to a previous study using mechanically pumped liquid pheromone. Finally, the polymer emitters tended to dissolve unevenly in high flow conditions. We demonstrate that housing the emitter stabilizes the dissolution rate at high water velocity. We conclude the performance characteristics of PEG emitters to achieve controlled-release of a semiochemical are sufficient to recommend its use in conservation and management activities related to native and invasive aquatic organisms.

  5. Neurophysiological mechanisms underlying sex- and maturation-related variation in pheromone responses in honey bees (Apis mellifera).

    Science.gov (United States)

    Villar, Gabriel; Baker, Thomas C; Patch, Harland M; Grozinger, Christina M

    2015-07-01

    In the honey bee (Apis mellifera), social organization is primarily mediated by pheromones. Queen-produced 9-oxo-2-decenoic acid (9-ODA) functions as both a social and sex pheromone, eliciting attraction in both female workers and male drones, but also affecting other critical aspects of worker physiology and behavior. These effects are also maturation related, as younger workers and sexually mature drones are most receptive to 9-ODA. While changes in the peripheral nervous system drive sex-related differences in sensitivity to 9-ODA, the mechanisms driving maturation-related shifts in receptivity to 9-ODA remain unknown. Here, we investigate the hypothesis that changes at the peripheral nervous system may be mediating plastic responses to 9-ODA by characterizing expression levels of AmOR11 (the olfactory receptor tuned to 9-ODA) and electrophysiological responses to 9-ODA. We find that receptor expression correlates significantly with behavioral receptivity to 9-ODA, with nurses and sexually mature drones exhibiting higher levels of expression than foragers and immature drones, respectively. Electrophysiological responses to 9-ODA were not found to correlate with behavioral receptivity or receptor expression, however. Thus, while receptor expression at the periphery exhibits a level of plasticity that correlates with behavior, the mechanisms driving maturation-dependent responsiveness to 9-ODA appear to function primarily in the central nervous system.

  6. Volatile-mediated interactions between phylogenetically different soil bacteria

    Directory of Open Access Journals (Sweden)

    Paolina eGarbeva

    2014-06-01

    Full Text Available There is increasing evidence that organic volatiles play an important role in interactions between micro-organisms in the porous soil matrix. Here we report that volatile compounds emitted by different soil bacteria can affect the growth, antibiotic production and gene expression of the soil bacterium Pseudomonas fluorescens Pf0-1. We applied a novel cultivation approach that mimics the natural nutritional heterogeneity in soil in which P. fluorescens grown on nutrient-limited agar was exposed to volatiles produced by 4 phylogenetically different bacterial isolates (Collimonas pratensis, Serratia plymuthica, Paenibacillus sp. and Pedobacter sp. growing in sand containing artificial root exudates. Contrary to our expectation, the produced volatiles stimulated rather than inhibited the growth of P. fluorescens. A genome-wide, microarray-based analysis revealed that volatiles of all 4 bacterial strains affected gene expression of P. fluorescens, but with a different pattern of gene expression for each strain. Based on the annotation of the differently expressed genes, bacterial volatiles appear to induce a chemotactic motility response in P. fluorescens, but also an oxidative stress response. A more detailed study revealed that volatiles produced by C. pratensis triggered, antimicrobial secondary metabolite production in P. fluorescens. Our results indicate that bacterial volatiles can have an important role in communication, trophic - and antagonistic interactions within the soil bacterial community.

  7. Transcriptome exploration of the sex pheromone gland of Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae).

    Science.gov (United States)

    González-Caballero, Natalia; Valenzuela, Jesus G; Ribeiro, José M C; Cuervo, Patricia; Brazil, Reginaldo P

    2013-03-07

    Molecules involved in pheromone biosynthesis may represent alternative targets for insect population control. This may be particularly useful in managing the reproduction of Lutzomyia longipalpis, the main vector of the protozoan parasite Leishmania infantum in Latin America. Besides the chemical identity of the major components of the L. longipalpis sex pheromone, there is no information regarding the molecular biology behind its production. To understand this process, obtaining information on which genes are expressed in the pheromone gland is essential. In this study we used a transcriptomic approach to explore the pheromone gland and adjacent abdominal tergites in order to obtain substantial general sequence information. We used a laboratory-reared L. longipalpis (one spot, 9-Methyl GermacreneB) population, captured in Lapinha Cave, state of Minas Gerais, Brazil for this analysis. From a total of 3,547 cDNA clones, 2,502 high quality sequences from the pheromone gland and adjacent tissues were obtained and assembled into 1,387 contigs. Through blast searches of public databases, a group of transcripts encoding proteins potentially involved in the production of terpenoid precursors were identified in the 4th abdominal tergite, the segment containing the pheromone gland. Among them, protein-coding transcripts for four enzymes of the mevalonate pathway such as 3-hydroxyl-3-methyl glutaryl CoA reductase, phosphomevalonate kinase, diphosphomevalonate descarboxylase, and isopentenyl pyrophosphate isomerase were identified. Moreover, transcripts coding for farnesyl diphosphate synthase and NADP+ dependent farnesol dehydrogenase were also found in the same tergite. Additionally, genes potentially involved in pheromone transportation were identified from the three abdominal tergites analyzed. This study constitutes the first transcriptomic analysis exploring the repertoire of genes expressed in the tissue containing the L. longipalpis pheromone gland as well as the

  8. Improved synthesis of (3E,6Z,9Z)-1,3,6,9-nonadecatetraene, attraction inhibitor of bruce spanworm, Operophtera bruceata, to pheromone traps for monitoring winter moth, Operophtera brumata.

    Science.gov (United States)

    Khrimian, Ashot; Lance, David R; Mastro, Victor C; Elkinton, Joseph S

    2010-02-10

    The winter moth, Operophtera brumata (Lepidoptera: Geometridae), is an early-season defoliator that attacks a wide variety of hardwoods and, in some cases, conifers. The insect is native to Europe but has become established in at least three areas of North America including southeastern New England. The female-produced sex attractant pheromone of the winter moth was identified as (3Z,6Z,9Z)-1,3,6,9-nonadecatetraene (1), which also attracts a native congener, the Bruce spanworm, Operophtera bruceata . Dissection, or (for certainty) DNA molecular testing, is required to differentiate between males of the two species. Thus, a trapping method that is selective for winter moth would be desirable. A geometric isomer of the pheromone, (3E,6Z,9Z)-1,3,6,9-nonadecatetraene (2), can reportedly inhibit attraction of Bruce spanworm to traps without affecting winter moth catch, but use of the pheromone and inhibitor together has not been optimized, nor has the synthesis of the inhibitor. This paper presents two new syntheses of the inhibitor (3E,6Z,9Z)-1,3,6,9-nonadecatetraene based on the intermediate (3Z,6Z)-3,6-hexadecadien-1-ol (4), which has also been utilized in the synthesis of the pheromone. The syntheses combine traditional acetylenic chemistry and Wittig olefination reactions. In one approach, 2 was synthesized in 80% purity (20% being pheromone 1), and in the second, tetraene 2 of 96% purity (and free of 1) was produced in 25% overall yield from dienol 4. The last method benefitted from a refined TEMPO-mediated PhI(OAc)(2) oxidation of 4 and a two-carbon homologation of the corresponding aldehyde 7.

  9. Assessment of waste management of volatile radionuclides

    International Nuclear Information System (INIS)

    Altomare, P.M.; Barbier, M.; Lord, N.; Nainan, D.

    1979-05-01

    This document presents a review of the Technologies for Waste Management of the Volatile Radionuclides of iodine-129, krypton-85, tritium, and carbon-14. The report presents an estimate of the quantities of these volatile radionuclides as are produced in the nuclear power industry. The various technologies as may be used, or which are under investigation, to immobilize these nuclides and to contain them during storage and in disposal are discussed. Also, the alternative disposal options as may be applied to isolate these radioactive wastes from the human environment are presented. The report contains information which was available through approximately January 1978

  10. Ready for a fight? The physiological effects of detecting an opponent's pheromone cues prior to a contest.

    Science.gov (United States)

    Garcia, Mark J; Williams, John; Sinderman, Benjamin; Earley, Ryan L

    2015-10-01

    Reception of pheromone cues can elicit significant physiological (e.g. steroid hormone levels) changes in the recipient. These pheromone-induced physiological changes have been well documented for male-female interactions, but scarcely in same-sex interactions (male-male and female-female). We sought to address this dearth in the current literature and examine whether mangrove rivulus fish (Kryptolebias marmoratus) could detect and, ultimately, mount a physiological response to the pheromone signature of a potential, same-sex competitor. We examined steroid hormone levels in mangrove rivulus exposed to one of three treatments: 1) isolation, 2) exposure to pheromones of a size-matched partner, and 3) pheromone exposure to a size-matched opponent followed by a physical encounter with the opponent. We found that exposure to a competitor's pheromone cues elicited a significant increase in testosterone levels. Increases in testosterone were similar across genetically distinct lineages derived from geographically distinct populations. Further, testosterone levels were similar between individuals only exposed to pheromone cues and individuals exposed to both pheromone cues and a subsequent physical encounter. Our findings led us to generate a number of testable predictions regarding how mangrove rivulus utilize pheromone signals in social interactions, the molecular mechanisms linking social stimuli and hormonal responses, and the possible adaptive benefits of hormonal responsiveness to receiving a potential competitor's pheromone cues. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Carbonaceous Asteroid Volatile Recovery (CAVoR) system, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The Carbonaceous Asteroid Volatile Recovery (CAVoR) system produces water and hydrogen-rich syngas for propellant production, life support consumables, and...

  12. Sodium channels as targets for volatile anesthetics

    Directory of Open Access Journals (Sweden)

    Karl F. Herold

    2012-03-01

    Full Text Available The molecular mechanisms of modern inhaled anesthetics although widely used in clinical settings are still poorly understood. Considerable evidence supports effects on membrane proteins such as ligand- and voltage-gated ion channels of excitable cells. Na+ channels are crucial to action potential initiation and propagation, and represent potential targets for volatile anesthetics. Inhibition of presynaptic Na+ channels leads to reduced neurotransmitter release at the synapse and could therefore contribute to the mechanisms by which volatile anesthetics produce their characteristic effects: amnesia, unconsciousness, and immobility. Early studies on crayfish and squid giant axon showed inhibition of Na+ currents by volatile anesthetics. Subsequent studies using native neuronal preparations and heterologous expression systems with various mammalian Na+ channel isoforms implicated inhibition of presynaptic Na+ channels in anesthetic actions. Volatile anesthetics reduce peak Na+ current and shift the voltage of half-maximal steady-state inactivation towards more negative potentials, thus stabilizing the fast-inactivated state. Furthermore recovery from fast-inactivation is slowed together with an enhanced use-dependent block during pulse train protocols. These effects can reduce neurotransmitter release by depressing presynaptic excitability, depolarization and Ca entry, and ultimately transmitter release. This reduction in transmitter release is more portent for glutamatergic vs. GABAergic terminals. Involvement of Na+ channel inhibition in mediating the immobility caused by volatile anesthetics has been demonstrated in animal studies, in which intrathecal infusion of the Na+ channel blocker tetrodotoxin increases volatile anesthetic potency, whereas infusion of the Na+ channels agonist veratridine reduces anesthetic potency. These studies indicate that inhibition of presynaptic Na+ channels by volatile anesthetics is involved in mediating some of

  13. Volatile liquid storage system

    International Nuclear Information System (INIS)

    Laverman, R.J.; Winters, P.J.; Rinehart, J.K.

    1992-01-01

    This patent describes a method of collecting and abating emission from a volatile liquid in an above ground storage tank. It comprises the liquid storage tank having a bottom, a vertical cylindrical circular wall having a lower edge portion joined to the bottom, and an external fixed roof, the tank having an internal floating roof floating on a volatile liquid stored in the tank, and air vent means in the tank in communication with a vapor space in the tank constituting at least the space above the floating roof when the floating roof floats on a predetermined maximum volume of volatile liquid in the tank; permitting ambient air; pumping emission laden air from the tank vapor space above the floating roof; and by means of the emissions abatement apparatus eliminating most of the emission from the emissions laden air with formation of a gaseous effluent and then discharging the resulting gaseous effluent to the atmosphere

  14. Understanding Interest Rate Volatility

    DEFF Research Database (Denmark)

    Volker, Desi

    This thesis is the result of my Ph.D. studies at the Department of Finance of the Copenhagen Business School. It consists of three essays covering topics related to the term structure of interest rates, monetary policy and interest rate volatility. The rst essay, \\Monetary Policy Uncertainty...... and Interest Rates", examines the role of monetary policy uncertainty on the term structure of interest rates. The second essay, \\A Regime-Switching A ne Term Structure Model with Stochastic Volatility" (co-authored with Sebastian Fux), investigates the ability of the class of regime switching models...... with and without stochastic volatility to capture the main stylized features of U.S. interest rates. The third essay, \\Variance Risk Premia in the Interest Rate Swap Market", investigates the time-series and cross-sectional properties of the compensation demanded for holding interest rate variance risk. The essays...

  15. Price volatility in wind dominant electricity markets

    DEFF Research Database (Denmark)

    Farashbashi-Astaneh, Seyed-Mostafa; Chen, Zhe

    2013-01-01

    High penetration of intermittent renewable energy sources causes price volatility in future electricity markets. This is specially the case in European countries that plan high penetration levels. This highlights the necessity for revising market regulations and mechanisms in accordance...... to generation combination portfolio. Proposed solutions should be able to tackle with emerging challenges which are mainly due to high variability and unpredictability of intermittent renewable resources. In this paper high price volatility will be introduced as an emerging challenge in wind dominant...... electricity markets. High price volatility is unappreciated because it imposes high financial risk levels to both electricity consumers and producers. Additionally high price variations impede tracking price signals by consumers in future smart grid and jeopardize implementation of demand response concepts...

  16. The water-borne protein signals (pheromones) of the Antarctic ciliated protozoan Euplotes nobilii: structure of the gene coding for the En-6 pheromone.

    Science.gov (United States)

    La Terza, Antonietta; Dobri, Nicoleta; Alimenti, Claudio; Vallesi, Adriana; Luporini, Pierangelo

    2009-01-01

    The marine Antarctic ciliate, Euplotes nobilii, secretes a family of water-borne signal proteins, denoted as pheromones, which control vegetative proliferation and mating in the cell. Based on the knowledge of the amino acid sequences of a set of these pheromones isolated from the culture supernatant of wild-type strains, we designed probes to identify their encoding genes in the cell somatic nucleus (macronucleus). The full-length gene of the pheromone En-6 was determined and found to contain an open-reading frame specific for the synthesis of the En-6 cytoplasmic precursor (pre-pro-En-6), which requires 2 proteolytic cleavages to remove the signal peptide (pre) and the prosegment before secretion of the mature protein. In contrast to the sequence variability that distinguishes the secreted pheromones, the pre- and pro-sequences appear to be tightly conserved and useful for the construction of probes to clone every other E. nobilii pheromone gene. Potential intron sequences in the coding region of the En-6 gene imply the synthesis of more En-6 isoforms.

  17. Nitrogen Trifluoride-Based Fluoride- Volatility Separations Process: Initial Studies

    Energy Technology Data Exchange (ETDEWEB)

    McNamara, Bruce K.; Scheele, Randall D.; Casella, Andrew M.; Kozelisky, Anne E.

    2011-09-28

    This document describes the results of our investigations on the potential use of nitrogen trifluoride as the fluorinating and oxidizing agent in fluoride volatility-based used nuclear fuel reprocessing. The conceptual process uses differences in reaction temperatures between nitrogen trifluoride and fuel constituents that produce volatile fluorides to achieve separations and recover valuable constituents. We provide results from our thermodynamic evaluations, thermo-analytical experiments, kinetic models, and provide a preliminary process flowsheet. The evaluations found that nitrogen trifluoride can effectively produce volatile fluorides at different temperatures dependent on the fuel constituent.

  18. Pricing Volatility of Stock Returns with Volatile and Persistent Components

    DEFF Research Database (Denmark)

    Zhu, Jie

    2009-01-01

    This paper introduces a two-component volatility model based on first moments of both components to describe the dynamics of speculative return volatility. The two components capture the volatile and the persistent part of volatility, respectively. The model is applied to 10 Asia-Pacific stock ma...... markets. A positive or risk-premium effect exists between the return and the volatile component, yet the persistent component is not significantly priced for the return dynamic process....... markets. Their in-mean effects on returns are tested. The empirical results show that the persistent component is much more important for the volatility dynamic process than is the volatile component. However, the volatile component is found to be a significant pricing factor of asset returns for most...

  19. Pricing Volatility of Stock Returns with Volatile and Persistent Components

    DEFF Research Database (Denmark)

    Zhu, Jie

    In this paper a two-component volatility model based on the component's first moment is introduced to describe the dynamic of speculative return volatility. The two components capture the volatile and persistent part of volatility respectively. Then the model is applied to 10 Asia-Pacific stock m......, a positive or risk-premium effect exists between return and the volatile component, yet the persistent component is not significantly priced for return dynamic process....... markets. Their in-mean effects on return are also tested. The empirical results show that the persistent component accounts much more for volatility dynamic process than the volatile component. However the volatile component is found to be a significant pricing factor of asset returns for most markets...

  20. Evidence for sex pheromones and inbreeding avoidance in select North America yellowjacket species (Hymenoptera: Vespidae)

    Science.gov (United States)

    Little is known about the roles of sex pheromones in mate-finding behavior of social wasps (Vespidae). Working with the aerial yellowjacket, Dolichovespula arenaria (Fabricius), baldfaced hornet, D. maculata (L.), western yellowjacket, Vespula pensylvanica (Saussure), southern yellowjacket, V. squam...

  1. Pigment-dispersing factor modulates pheromone production in clock cells that influence mating in Drosophila

    NARCIS (Netherlands)

    Krupp, Joshua J.; Billeter, Jean-Christophe; Wong, Amy; Choi, Charles; Nitabach, Michael N.; Levine, Joel D.

    2013-01-01

    Social cues contribute to the circadian entrainment of physiological and behavioral rhythms. These cues supplement the influence of daily and seasonal cycles in light and temperature. In Drosophila, the social environment modulates circadian mechanisms that regulate sex pheromone production and

  2. Tracking of Fluid-Advected Odor Plumes: Strategies Inspired by Insect Orientation to Pheromone

    National Research Council Canada - National Science Library

    Li, Wei

    2002-01-01

    .... These strategies are inspired by the maneuvers of moths flying upwind along a pheromone plume. Although moth maneuvers are well documented, the mechanisms underlying sensory perception and navigation are not fully understood...

  3. Pheromone application in prevention and therapy of domestic animal behavioral disorder

    Directory of Open Access Journals (Sweden)

    Vučinić Marijana

    2007-01-01

    Full Text Available This review-type paper presents the latest knowledge on pheromone therapy. Pheromone therapy does not imply merely the use of structural analogues of pheromones in therapy, but also in the prevention of behavioral disorders in domestic animals. Their application is induced in all cases in which the effects of stressors are expected and their negative effect on the health condition, welfare and production results of domestic animals. Structural analogues of pheromones can successfully be applied in the prevention and therapy of behavioral disorders in horses, swine, dogs, and cats. Recent investigations have confirmed that structural analogues of semiochemicals exert a positive effect also on the production results and meat quality of broilers. They realize their therapeutic and preventive effect on the behavior of domestic animals through the stabilization of the emotional state, relaxation, and calming the animals that are disturbed, or could become disturbed due to the effect of stressors.

  4. Field dispersal ability and taxis to sex pheromone of irradiated F-1 male Asian corn borer

    International Nuclear Information System (INIS)

    Wang Huasong; Liu Qiongru; Lu Daguang; Wang Endong; Kang Wen; Li Yongjun; He Qiulan; Hu Jianguo

    1998-01-01

    The dispersal ability of F-1 male Asian corn borer, Ostrinia furnacalis (Guenee), irradiated with 100, 150 and 200 Gy Separately in parental generation were tested by marking (with Calco oil red or Sudan blue internally)-releasing-recapturing (with synthesized sex pheromone) method in the field where the farthest distance from release point to pheromone trap was 550 m. The results showed that, as compared with the normal male moths, despite of the fact that a part of the irradiated F-1 males had lost dispersal ability or taxis to sex pheromone, there was no significant difference between the captured rates of irradiated F-1 males and normal males in the trap 550 m from release point, indicated that the dispersal ability or taxis to sex pheromone of irradiated F-1 males arrived at 550 m from release point are still well matched with the normal ones

  5. Trail pheromone of the leaf-cutting ant,Acromyrmex octospinosus (Reich), (Formicidae: Myrmicinae).

    Science.gov (United States)

    Cross, J H; West, J R; Silverstein, R M; Jutsum, A R; Cherrett, J M

    1982-08-01

    The most active component of the trail pheromone of the leafcutting ant,Acromyrmex octospinosus, is methyl 4-methylpyrrole-2-carboxylate (I). Two pyrazine isomers (II) and (III) are present but inactive.

  6. The Lutzomyia longipalpis complex: a brief natural history of aggregation-sex pheromone communication.

    Science.gov (United States)

    Spiegel, Carolina N; Dias, Denise B Dos Santos; Araki, Alejandra S; Hamilton, James G C; Brazil, Reginaldo P; Jones, Théresa M

    2016-11-14

    In this paper we review the natural history of pheromone communication and the current diversity of aggregation-sex pheromones in the sand fly Lutzomyia longipalpis. This species complex is the main vector of Leishmania infantum, the agent of visceral leishmaniasis in the Americas. The identification of variation in pheromone chemotypes combined with molecular and sound analyses have all contributed to our understanding of the extent of divergence among cryptic members of this complex. The importance of chemical signals as pre-mating barriers and drivers of speciation is discussed. Moreover, the importance of aggregation-sex pheromones as sexually selected signals is highlighted with evidence from the literature suggesting their potential role in species and mate recognition as well as mate assessment. The distinct evolutionary forces possibly involved are briefly reviewed and discussed in the context of this intriguing insect.

  7. Alterations in premating behavior and pheromone biology of gamma-irradiated Trichoplusia ni (Lepidoptera:Noctuidae)

    International Nuclear Information System (INIS)

    Szentesi, A.; McLaughlin, J.R.; Coffelt, J.A.

    1977-01-01

    Exposure of female cabbage looper pupae, Trichoplusia ni, to gamma irradiation at 0 to 72 hr before eclosion resulted in significantly reduced moving and calling activity of the adults. The effects were dose-related from 10 to 40 kR. Generally, irradiation in a nitrogen atmosphere slightly reduced deleterious effects, but fractionation of the radiation dose did not. Four-day-old irradiated females contained significantly more sex pheromone than untreated females, indicating that loss of pheromone is positively correlated to the amount of calling activity. Males exposed to 20 kR or 40 kR in nitrogen were not affected in their flight response in an olfactometer to a level of synthetic pheromone ca. equal to that released by a calling female or to 0.1 x this level. The response of males exposed to 40 kR in air, however, was significantly decreased at the lower pheromone concentration

  8. Synthetic sex pheromone attracts the leishmaniasis vector Lutzomyia longipalpis to experimental chicken sheds treated with insecticide

    Directory of Open Access Journals (Sweden)

    Brazil Reginaldo P

    2010-03-01

    Full Text Available Abstract Background Current strategies for controlling American visceral leishmaniasis (AVL have been unable to prevent the spread of the disease across Brazil. With no effective vaccine and culling of infected dogs an unpopular and unsuccessful alternative, new tools are urgently needed to manage populations of the sand fly vector, Lutzomyia longipalpis Lutz and Neiva (Diptera: Psychodidae. Here, we test two potential strategies for improving L. longipalpis control using the synthetic sand fly pheromone (±-9-methylgermacrene-B: the first in conjunction with spraying of animal houses with insecticide, the second using coloured sticky traps. Results Addition of synthetic pheromone resulted in greater numbers of male and female sand flies being caught and killed at experimental chicken sheds sprayed with insecticide, compared to pheromone-less controls. Furthermore, a ten-fold increase in the amount of sex pheromone released from test sheds increased the number of females attracted and subsequently killed. Treating sheds with insecticide alone resulted in a significant decrease in numbers of males attracted to sheds (compared to pre-spraying levels, and a near significant decrease in numbers of females. However, this effect was reversed through addition of synthetic pheromone at the time of insecticide spraying, leading to an increase in number of flies attracted post-treatment. In field trials of commercially available different coloured sticky traps, yellow traps caught more males than blue traps when placed in chicken sheds. In addition, yellow traps fitted with 10 pheromone lures caught significantly more males than pheromone-less controls. However, while female sand flies showed a preference for both blue and yellow pheromone traps sticky traps over white traps in the laboratory, neither colour caught significant numbers of females in chicken sheds, either with or without pheromone. Conclusions We conclude that synthetic pheromone could

  9. Factors Affecting sex pheromone production in female cotton leaf worm moth, Spodoptera littoralis (boisd.)

    International Nuclear Information System (INIS)

    Sallam, H.A.; Hazaa, M.A.; Abd El-Rahman, H.A.; Hussein, M.A.

    2000-01-01

    Factors influencing sex pheromone production in the cotton leaf worm female moth with emphasis on gamma radiation were investigated. To determine the effect of age on sex pheromone production, ether extracts of the female abdominal tips were prepared from virgin females of various ages in a concentration of 0.01 FE/mu L. Each female extract was tested against 1-2 days-old males. The obtained results indicated that virgin females could secrete sex pheromone early at the beginning of their life. The pheromone production increased rapidly to reach its maximum on the second day. To study the effect of daytime on sex pheromone production, the ether extracts of 1-2 days old virgin female abdominal tips were prepared at 3 hour-intervals, throughout the photo phase and scotophase in a concentration of 0.01 FE/mu L. The obtained results indicated that pheromone production showed a minimum concentration at mid-day during the photo phase. It then increased to a moderate concentration from 7:0 p.m. to 10:0 p.m. and reached its maximum titer at almost mid-night. The obtained data on the effect of gamma irradiation indicated that irradiation of 3 and 6-day-old female pupae with doses of 60 and 120 Gy, respectively caused a reduction of 28.1 and 27.3 % in male response, respectively, to female sex pheromone extracts. When full-grown female pupae were irradiated with 200 and 350 Gy, a reduction of 15.6 and 75% in male response, respectively, was reached. Thus, an irradiation dose of 350 Gy applied to full-grown female pupae could severely affect pheromone production of the emerging female moths

  10. Phylogenetic distribution of a male pheromone that may exploit a nonsexual preference in lampreys.

    Science.gov (United States)

    Buchinger, T J; Bussy, U; Li, K; Wang, H; Huertas, M; Baker, C F; Jia, L; Hayes, M C; Li, W; Johnson, N S

    2017-12-01

    Pheromones are among the most important sexual signals used by organisms throughout the animal kingdom. However, few are identified in vertebrates, leaving the evolutionary mechanisms underlying vertebrate pheromones poorly understood. Pre-existing biases in receivers' perceptual systems shape visual and auditory signalling systems, but studies on how receiver biases influence the evolution of pheromone communication remain sparse. The lamprey Petromyzon marinus uses a relatively well-understood suite of pheromones and offers a unique opportunity to study the evolution of vertebrate pheromone communication. Previous studies indicate that male signalling with the mating pheromone 3-keto petromyzonol sulphate (3kPZS) may exploit a nonsexual attraction to juvenile-released 3kPZS that guides migration into productive rearing habitat. Here, we infer the distribution of male signalling with 3kPZS using a phylogenetic comparison comprising six of 10 genera and two of three families. Our results indicate that only P. marinus and Ichthyomyzon castaneus release 3kPZS at high rates. Olfactory and behavioural assays with P. marinus, I. castaneus and a subset of three other species that do not use 3kPZS as a sexual signal indicate that male signalling might have driven the evolution of female adaptations to detect 3kPZS with specific olfactory mechanisms and respond to 3kPZS with targeted attraction relevant during mate search. We postulate that 3kPZS communication evolved independently in I. castaneus and P. marinus, but cannot eliminate the alternative that other species lost 3kPZS communication. Regardless, our results represent a rare macroevolutionary investigation of a vertebrate pheromone and provide insight into the evolutionary mechanisms underlying pheromone communication. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  11. Allelic exchange of pheromones and their receptors reprograms sexual identity in Cryptococcus neoformans.

    Directory of Open Access Journals (Sweden)

    Brynne C Stanton

    2010-02-01

    Full Text Available Cell type specification is a fundamental process that all cells must carry out to ensure appropriate behaviors in response to environmental stimuli. In fungi, cell identity is critical for defining "sexes" known as mating types and is controlled by components of mating type (MAT loci. MAT-encoded genes function to define sexes via two distinct paradigms: 1 by controlling transcription of components common to both sexes, or 2 by expressing specially encoded factors (pheromones and their receptors that differ between mating types. The human fungal pathogen Cryptococcus neoformans has two mating types (a and alpha that are specified by an extremely unusual MAT locus. The complex architecture of this locus makes it impossible to predict which paradigm governs mating type. To identify the mechanism by which the C. neoformans sexes are determined, we created strains in which the pheromone and pheromone receptor from one mating type (a replaced the pheromone and pheromone receptor of the other (alpha. We discovered that these "alpha(a" cells effectively adopt a new mating type (that of a cells; they sense and respond to alpha factor, they elicit a mating response from alpha cells, and they fuse with alpha cells. In addition, alpha(a cells lose the alpha cell type-specific response to pheromone and do not form germ tubes, instead remaining spherical like a cells. Finally, we discovered that exogenous expression of the diploid/dikaryon-specific transcription factor Sxi2a could then promote complete sexual development in crosses between alpha and alpha(a strains. These data reveal that cell identity in C. neoformans is controlled fully by three kinds of MAT-encoded proteins: pheromones, pheromone receptors, and homeodomain proteins. Our findings establish the mechanisms for maintenance of distinct cell types and subsequent developmental behaviors in this unusual human fungal pathogen.

  12. An anti-steroidogenic inhibitory primer pheromone in male sea lamprey (Petromyzon marinus)

    Science.gov (United States)

    Chung-Davidson, Yu-Wen; Wang, Huiyong; Bryan, Mara B.; Wu, Hong; Johnson, Nicholas S.; Li, Weiming

    2013-01-01

    Reproductive functions can be modulated by both stimulatory and inhibitory primer pheromones released by conspecifics. Many stimulatory primer pheromones have been documented, but relatively few inhibitory primer pheromones have been reported in vertebrates. The sea lamprey male sex pheromone system presents an advantageous model to explore the stimulatory and inhibitory primer pheromone functions in vertebrates since several pheromone components have been identified. We hypothesized that a candidate sex pheromone component, 7α, 12α-dihydroxy-5α-cholan-3-one-24-oic acid (3 keto-allocholic acid or 3kACA), exerts priming effects through the hypothalamic-pituitary-gonadal (HPG) axis. To test this hypothesis, we measured the peptide concentrations and gene expressions of lamprey gonadotropin releasing hormones (lGnRH) and the HPG output in immature male sea lamprey exposed to waterborne 3kACA. Exposure to waterborne 3kACA altered neuronal activation markers such as jun and jun N-terminal kinase (JNK), and lGnRH mRNA levels in the brain. Waterborne 3kACA also increased lGnRH-III, but not lGnRH-I or -II, in the forebrain. In the plasma, 3kACA exposure decreased all three lGnRH peptide concentrations after 1 h exposure. After 2 h exposure, 3kACA increased lGnRHI and -III, but decreased lGnRH-II peptide concentrations in the plasma. Plasma lGnRH peptide concentrations showed differential phasic patterns. Group housing condition appeared to increase the averaged plasma lGnRH levels in male sea lamprey compared to isolated males. Interestingly, 15α-hydroxyprogesterone (15α-P) concentrations decreased after prolonged 3kACA exposure (at least 24 h). To our knowledge, this is the only known synthetic vertebrate pheromone component that inhibits steroidogenesis in males.

  13. Allelic exchange of pheromones and their receptors reprograms sexual identity in Cryptococcus neoformans.

    Science.gov (United States)

    Stanton, Brynne C; Giles, Steven S; Staudt, Mark W; Kruzel, Emilia K; Hull, Christina M

    2010-02-26

    Cell type specification is a fundamental process that all cells must carry out to ensure appropriate behaviors in response to environmental stimuli. In fungi, cell identity is critical for defining "sexes" known as mating types and is controlled by components of mating type (MAT) loci. MAT-encoded genes function to define sexes via two distinct paradigms: 1) by controlling transcription of components common to both sexes, or 2) by expressing specially encoded factors (pheromones and their receptors) that differ between mating types. The human fungal pathogen Cryptococcus neoformans has two mating types (a and alpha) that are specified by an extremely unusual MAT locus. The complex architecture of this locus makes it impossible to predict which paradigm governs mating type. To identify the mechanism by which the C. neoformans sexes are determined, we created strains in which the pheromone and pheromone receptor from one mating type (a) replaced the pheromone and pheromone receptor of the other (alpha). We discovered that these "alpha(a)" cells effectively adopt a new mating type (that of a cells); they sense and respond to alpha factor, they elicit a mating response from alpha cells, and they fuse with alpha cells. In addition, alpha(a) cells lose the alpha cell type-specific response to pheromone and do not form germ tubes, instead remaining spherical like a cells. Finally, we discovered that exogenous expression of the diploid/dikaryon-specific transcription factor Sxi2a could then promote complete sexual development in crosses between alpha and alpha(a) strains. These data reveal that cell identity in C. neoformans is controlled fully by three kinds of MAT-encoded proteins: pheromones, pheromone receptors, and homeodomain proteins. Our findings establish the mechanisms for maintenance of distinct cell types and subsequent developmental behaviors in this unusual human fungal pathogen.

  14. Quantifying requirements volatility effects

    NARCIS (Netherlands)

    Kulk, G.P.; Verhoef, C.

    2008-01-01

    In an organization operating in the bancassurance sector we identified a low-risk IT subportfolio of 84 IT projects comprising together 16,500 function points, each project varying in size and duration, for which we were able to quantify its requirements volatility. This representative portfolio

  15. Idiosyncratic Volatility Puzzle

    DEFF Research Database (Denmark)

    Aslanidis, Nektarios; Christiansen, Charlotte; Lambertides, Neophytos

    from a large pool of macroeconomic and Önancial variables. Cleaning for macro-Önance e§ects reverses the puzzling negative relation between returns and idiosyncratic volatility documented previously. Portfolio analysis shows that the e§ects from macro-Önance factors are economically strong...

  16. Manure application and ammonia volatilization

    NARCIS (Netherlands)

    Huijsmans, J.F.M.

    2003-01-01

    Keywords: manure application, ammonia volatilization, environmental conditions, application technique, incorporation technique, draught force, work organization, costs Livestock manure applied on farmland is an important source of ammonia (NH3) volatilization, and NH3 is a major atmospheric

  17. Male sex pheromone components in Heliconius butterflies released by the androconia affect female choice

    Directory of Open Access Journals (Sweden)

    Kathy Darragh

    2017-11-01

    Full Text Available Sex-specific pheromones are known to play an important role in butterfly courtship, and may influence both individual reproductive success and reproductive isolation between species. Extensive ecological, behavioural and genetic studies of Heliconius butterflies have made a substantial contribution to our understanding of speciation. Male pheromones, although long suspected to play an important role, have received relatively little attention in this genus. Here, we combine morphological, chemical and behavioural analyses of male pheromones in the Neotropical butterfly Heliconius melpomene. First, we identify putative androconia that are specialized brush-like scales that lie within the shiny grey region of the male hindwing. We then describe putative male sex pheromone compounds, which are largely confined to the androconial region of the hindwing of mature males, but are absent in immature males and females. Finally, behavioural choice experiments reveal that females of H. melpomene, H. erato and H. timareta strongly discriminate against conspecific males which have their androconial region experimentally blocked. As well as demonstrating the importance of chemical signalling for female mate choice in Heliconius butterflies, the results describe structures involved in release of the pheromone and a list of potential male sex pheromone compounds.

  18. Short-chain alkanes synergise responses of moth pests to their sex pheromones.

    Science.gov (United States)

    Gurba, Alexandre; Guerin, Patrick M

    2016-05-01

    The use of sex pheromones for mating disruption of moth pests of crops is increasing worldwide. Efforts are under way to augment the efficiency and reliability of this control method by adding molecules derived from host plants to the sex attractants in dispensers. We show how attraction of the European grapevine moth, Lobesia botrana Den. & Schiff., and the codling moth, Cydia pomonella L., males to underdosed levels of their sex pheromones is increased by adding heptane or octane over a range of release rates. Pheromone-alkane mixtures enhance male recruitment by up to 30%, reaching levels induced by calling females, and shorten the flight time to the sex attractant by a factor of 2. The findings show the promise of using short-chain alkanes as pheromone synergists for mating disruption of insect pests of food crops. Alkane-pheromone combinations are expected to increase the competitiveness of dispensers with females, and to reduce the amount of pheromone needed for the control of these pests. © 2015 Society of Chemical Industry.

  19. Neural correlates underlying naloxone-induced amelioration of sexual behavior deterioration due to an alarm pheromone

    Directory of Open Access Journals (Sweden)

    Tatsuya eKobayashi

    2015-02-01

    Full Text Available Sexual behavior is suppressed by various types of stressors. We previously demonstrated that an alarm pheromone released by stressed male Wistar rats is a stressor to other rats, increases the number of mounts needed for ejaculation, and decreases the hit rate (described as the number of intromissions/sum of the mounts and intromissions. This deterioration in sexual behavior was ameliorated by pretreatment with the opioid receptor antagonist naloxone. However, the neural mechanism underlying this remains to be elucidated. Here, we examined Fos expression in 31 brain regions of pheromone-exposed rats and naloxone-pretreated pheromone-exposed rats 60 min after 10 intromissions. As previously reported, the alarm pheromone increased the number of mounts and decreased the hit rate. In addition, Fos expression was increases in the anterior medial division, anterior lateral division and posterior division of the bed nucleus of the stria terminalis, parvocellular part of the paraventricular nucleus of the hypothalamus, arcuate nucleus, dorsolateral and ventrolateral periaqueductal gray, and nucleus paragigantocellularis. Fos expression decreased in the magnocellular part of the paraventricular nucleus of the hypothalamus. Pretreatment with naloxone blocked the pheromone-induced changes in Fos expression in the magnocellular part of the paraventricular nucleus of the hypothalamus, ventrolateral periaqueductal gray, and nucleus paragigantocellularis. Based on these results, we hypothesize that the alarm pheromone deteriorated sexual behavior by activating the ventrolateral periaqueductal gray-nucleus paragigantocellularis cluster and suppressing the magnocellular part of the paraventricular nucleus of the hypothalamus via the opioidergic pathway.

  20. Assessment of commercially available pheromone lures for monitoring diamondback moth (Lepidoptera: Plutellidae) in canola.

    Science.gov (United States)

    Evenden, M L; Gries, R

    2010-06-01

    Sex pheromone monitoring lures from five different commercial sources were compared for their attractiveness to male diamondback moth, Plutella xylostella L. (Lepidoptera: Plutellidae) in canola, Brassica napus L., fields in western Canada. Lures that had the highest pheromone release rate, as determined by aeration analyses in the laboratory, were the least attractive in field tests. Lures from all the commercial sources tested released more (Z)-11-hexadecenal than (Z)-11-hexadecenyl acetate and the most attractive lures released a significantly higher aldehyde to acetate ratio than less attractive lures. Traps baited with sex pheromone lures from APTIV Inc. (Portland, OR) and ConTech Enterprises Inc. (Delta, BC, Canada) consistently captured more male diamondback moths than traps baited with lures from the other sources tested. In two different lure longevity field trapping experiments, older lures were more attractive to male diamondback moths than fresh lures. Pheromone release from aged lures was constant at very low release rates. The most attractive commercially available sex pheromone lures tested attracted fewer diamondback moth males than calling virgin female moths suggesting that research on the development of a more attractive synthetic sex pheromone lure is warranted.

  1. Attraction Pheromone of The Benthic Diatom Seminavis robusta: Studies on Structure-Activity Relationships.

    Science.gov (United States)

    Lembke, Christine; Stettin, Daniel; Speck, Franziska; Ueberschaar, Nico; De Decker, Sam; Vyverman, Wim; Pohnert, Georg

    2018-04-01

    Recently the first pheromone of a marine diatom was identified to be the diketopiperazine (S,S)-diproline. This compound facilitates attraction between mating partners in the benthic diatom Seminavis robusta. Interestingly, sexualized S. robusta cells are attracted to both the natural pheromone (S,S)-diproline as well as to its enantiomer (R,R)-diproline. Usually stereospecificity is a prerequisite for successful substrate-receptor interactions, and especially pheromone perception is often highly enantioselective. Here we introduce a structure-activity relationship study, to learn more about the principles of pheromone reception in diatoms. We analyzed the activity of nine different diketopiperazines in attraction and interference assays. The pheromone diproline itself, as well as a pipecolic acid derived diketopiperazine with two expanded aliphatic ring systems, showed the highest attractivity. Hydroxylatoin of the aliphatic rings abolished any bioactivity. Diketopiperazines derived from acyclic amino acids were not attrative as well. All stereoisomers of both the diproline and the pipecolic acid derived diketopiperazine were purified by enantioselective high-performance liquid chromatography, and application in bioactivity tests confirmed that attraction pheromone perception in this diatom is indeed not stereospecific. However, the lack of activity of diketopiperazines derived from acyclic amino acids suggests a specificity that prevents misguidance to sources of other naturally occurring diketopiperazines.

  2. Effect of gamma irradiation on scent gland development and pheromone production in Spodoptera Littoralis

    International Nuclear Information System (INIS)

    Hazaa, M.A.M.

    1995-01-01

    The cotton leaf worm, Spodoptera Littoralis (Boisd) is one of the important pests of cotton and many other crops in egypt. Several methods have been tried for its control. Among these, the sterile insect technique and the application of sex attractant pheromones appeared to be promissing in an integrated programme for the control of this and other serious insect pests. The high doses of gamma radiation required in such technique may affect some physiological and biological aspects of the insect as well; specially its reproductive potential. This effect may disturb the intraspecific communication between males and females by adversely affecting pheromone glands and hence pheromone production (Stimman et al., 1972; abdu et al., 1985 and El - Degwi, 1990). Insect sex pheromones are chemical substances secreted by either sex to attract the other sex and get them together for copulation. Trials to seek some of the factors that can prevent such communication in the cotton leaf worm may be of importance in its integrated control programme. This stimulated the present study to investigate the effect of gamma radiation doses on sex pheromone gland and pheromone production in this economically important insect pest.8 tabs., 14 figs., 92 refs

  3. Aggressive reproductive competition among hopelessly queenless honeybee workers triggered by pheromone signaling

    Science.gov (United States)

    Malka, O.; Shnieor, S.; Katzav-Gozansky, T.; Hefetz, A.

    2008-06-01

    In the honeybee, Apis mellifera, the queen monopolizes reproduction, while the sterile workers cooperate harmoniously in nest maintenance. However, under queenless (QL) conditions, cooperation collapses and reproductive competition among workers ensues. This is mediated through aggression and worker oviposition, as well as shifts in pheromones, from worker to queen-like composition. Many studies suggest a dichotomy between conflict resolution through aggression or through pheromonal signaling. In this paper, we demonstrate that both phenomena comprise essential components of reproductive competition and that pheromone signaling actually triggers the onset of aggression. We kept workers as QL groups until first aggression was observed and subsequently determined the contestants’ reproductive status and content of the mandibular (MG) and Dufour’s glands (DG). In groups in which aggression occurred early, the attacked bee had consistently more queen-like pheromone in both the MG and DG, although both contestants had undeveloped ovaries. In groups with late aggression, the attacked bee had consistently larger oocytes and more queen-like pheromone in the DG, but not the MG. We suggest that at early stages of competition, the MG secretion is utilized to establish dominance and that the DG provides an honest fertility signal. We further argue that it is the higher amount of DG pheromone that triggers aggression.

  4. The Effect of Trail Pheromone and Path Confinement on Learning of Complex Routes in the Ant Lasius niger.

    Science.gov (United States)

    Czaczkes, Tomer J; Weichselgartner, Tobias; Bernadou, Abel; Heinze, Jürgen

    2016-01-01

    Route learning is key to the survival of many central place foragers, such as bees and many ants. For ants which lay pheromone trails, the presence of a trail may act as an important source of information about whether an error has been made. The presence of trail pheromone has been demonstrated to support route learning, and the effect of pheromones on route choice have been reported to persist even after the pheromones have been removed. This could be explained in two ways: the pheromone may constrain the ants onto the correct route, thus preventing errors and aiding learning. Alternatively, the pheromones may act as a 'reassurance', signalling that the learner is on the right path and that learning the path is worthwhile. Here, we disentangle pheromone presence from route confinement in order to test these hypotheses, using the ant Lasius niger as a model. Unexpectedly, we did not find any evidence that pheromones support route learning. Indeed, there was no evidence that ants confined to the correct route learned at all. Thus, while we cannot support the 'reassurance' hypothesis, we can rule out the 'confinement' hypothesis. Other findings, such as a reduction in pheromone deposition in the presence of trail pheromones, are remarkably consistent with previous experiments. As previously reported, ants which make errors on their outward journey upregulate pheromone deposition on their return. Surprisingly, ants which would go on to make an error down-regulate pheromone deposition on their outward journey, hinting at a capacity for ants to gauge the quality of their own memories.

  5. The Effect of Trail Pheromone and Path Confinement on Learning of Complex Routes in the Ant Lasius niger.

    Directory of Open Access Journals (Sweden)

    Tomer J Czaczkes

    Full Text Available Route learning is key to the survival of many central place foragers, such as bees and many ants. For ants which lay pheromone trails, the presence of a trail may act as an important source of information about whether an error has been made. The presence of trail pheromone has been demonstrated to support route learning, and the effect of pheromones on route choice have been reported to persist even after the pheromones have been removed. This could be explained in two ways: the pheromone may constrain the ants onto the correct route, thus preventing errors and aiding learning. Alternatively, the pheromones may act as a 'reassurance', signalling that the learner is on the right path and that learning the path is worthwhile. Here, we disentangle pheromone presence from route confinement in order to test these hypotheses, using the ant Lasius niger as a model. Unexpectedly, we did not find any evidence that pheromones support route learning. Indeed, there was no evidence that ants confined to the correct route learned at all. Thus, while we cannot support the 'reassurance' hypothesis, we can rule out the 'confinement' hypothesis. Other findings, such as a reduction in pheromone deposition in the presence of trail pheromones, are remarkably consistent with previous experiments. As previously reported, ants which make errors on their outward journey upregulate pheromone deposition on their return. Surprisingly, ants which would go on to make an error down-regulate pheromone deposition on their outward journey, hinting at a capacity for ants to gauge the quality of their own memories.

  6. Potential Nematode Alarm Pheromone Induces Acute Avoidance in Caenorhabditis elegans.

    Science.gov (United States)

    Zhou, Ying; Loeza-Cabrera, Mario; Liu, Zheng; Aleman-Meza, Boanerges; Nguyen, Julie K; Jung, Sang-Kyu; Choi, Yuna; Shou, Qingyao; Butcher, Rebecca A; Zhong, Weiwei

    2017-07-01

    It is crucial for animal survival to detect dangers such as predators. A good indicator of dangers is injury of conspecifics. Here we show that fluids released from injured conspecifics invoke acute avoidance in both free-living and parasitic nematodes. Caenorhabditis elegans avoids extracts from closely related nematode species but not fruit fly larvae. The worm extracts have no impact on animal lifespan, suggesting that the worm extract may function as an alarm instead of inflicting physical harm. Avoidance of the worm extract requires the function of a cGMP signaling pathway that includes the cGMP-gated channel TAX-2/TAX-4 in the amphid sensory neurons ASI and ASK. Genetic evidence indicates that the avoidance behavior is modulated by the neurotransmitters GABA and serotonin, two common targets of anxiolytic drugs. Together, these data support a model that nematodes use a nematode-specific alarm pheromone to detect conspecific injury. Copyright © 2017 by the Genetics Society of America.

  7. Small-molecule pheromones and hormones controlling nematode development.

    Science.gov (United States)

    Butcher, Rebecca A

    2017-05-17

    The existence of small-molecule signals that influence development in Caenorhabditis elegans has been known for several decades, but only in recent years have the chemical structures of several of these signals been established. The identification of these signals has enabled connections to be made between these small molecules and fundamental signaling pathways in C. elegans that influence not only development but also metabolism, fertility, and lifespan. Spurred by these important discoveries and aided by recent advances in comparative metabolomics and NMR spectroscopy, the field of nematode chemistry has the potential to expand dramatically in the coming years. This Perspective will focus on small-molecule pheromones and hormones that influence developmental events in the nematode life cycle (ascarosides, dafachronic acids, and nemamides), will cover more recent work regarding the biosynthesis of these signals, and will explore how the discovery of these signals is transforming our understanding of nematode development and physiology.

  8. Different roles suggested by sex-biased expression and pheromone binding affinity among three pheromone binding proteins in the pink rice borer, Sesamia inferens (Walker) (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Jin, Jun-Yan; Li, Zhao-Qun; Zhang, Ya-Nan; Liu, Nai-Yong; Dong, Shuang-Lin

    2014-07-01

    Pheromone binding proteins (PBPs) are thought to bind and transport hydrophobic sex pheromone molecules across the aqueous sensillar lymph to specific pheromone receptors on the dendritic membrane of olfactory neurons. A maximum of 3 PBP genes have been consistently identified in noctuid species, and each of them shares high identity with its counterparts in other species within the family. The functionality differences of the 3 proteins are poorly understood. In the present study, 3 PBP cDNAs (SinfPBP1, 2, 3) were identified from the pink rice borer, Sesamia inferens, for the first time. The quantitative real-time PCR indicated that the 3 PBPs displayed similar temporal but very different sex related expression profiles. Expression of SinfPBP1 and SinfPBP2 were highly and moderately male biased, respectively, while SinfPBP3 was slightly female biased, as SinfPBPs were expressed at very different levels (PBP1>PBP2≫PBP3) in male antennae, but at similar levels in female antennae. Furthermore, the 3 SinfPBPs displayed different ligand binding profiles in fluorescence competitive binding assays. SinfPBP1 exhibited high and similar binding affinities to all 3 sex pheromone components (Ki=0.72-1.60 μM), while SinfPBP2 showed selective binding to the alcohol and aldehyde components (Ki=0.78-1.71 μM), and SinfPBP3 showed no obvious binding to the 3 sex pheromone components. The results suggest that SinfPBP1 plays a major role in the reception of female sex pheromones in S. inferens, while SinfPBP3 plays a least role (if any) and SinfPBP2 functions as a recognizer of alcohol and aldehyde components. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Arsenic volatilization in model anaerobic biogas digesters

    International Nuclear Information System (INIS)

    Mestrot, Adrien; Xie, Wan-Ying; Xue, Ximei; Zhu, Yong-Guan

    2013-01-01

    Highlights: • Arsenic is volatilized form all model anaerobic digesters, including the non-treated ones. • Volatile As species can be identified and quantified in all digesters. • Non-arsenic treated digesters volatilization rates are higher than Roxarsone treated ones. - Abstract: Arsenic is a class 1 non-threshold carcinogen which is highly ubiquitous. Arsenic undergoes many different transformations (biotic or abiotic) between and within environmental compartments, leading to a number of different chemical species possessing different properties and toxicities. One specific transformation is As biotic volatilization which is coupled with As biomethylation and has been scarcely studied due to inherent sampling issues. Arsenic methylation/volatilization is also linked with methanogenesis and occurs in anaerobic environments. In China, rice straw and animal manure are very often used to produce biogas and both can contain high amounts of As, especially if the rice is grown in areas with heavy mining or smelting industries and if Roxarsone is fed to the animals. Roxarsone is an As-containing drug which is widely used in China to control coccidian intestinal parasites, to improve feed efficiency and to promote rapid growth. Previous work has shown that this compound degrades to inorganic As under anaerobic conditions. In this study the focus is on biotic transformations of As in small microcosms designed as biogas digester models (BDMs) using recently validated As traps, thus, enabling direct quantification and identification of volatile As species. It is shown that although there was a loss of soluble As in the BDMs, their conditions favored biomethylation. All reactors produced volatile As, especially the monomethylarsonic acid spiked ones with 413 ± 148 ng As (mean ± SD, n = 3) which suggest that the first methylation step, from inorganic As, is a limiting factor. The most abundant species was trimethylarsine, but the toxic arsine was present in the

  10. The exploitation of volatile oil

    Institute of Scientific and Technical Information of China (English)

    MENG Teng; ZHANG Da; TENG Xiangjin; LINing; HAO Zaibin

    2007-01-01

    Rose is a kind of favorite ornamental plant. This article briefly introduced the cultivation and the use of rose around the world both in ancient time and nowadays. Today, volatile oil becomes the mainstream of the rose industry. People pay attention to the effect of volatile oil; meanwhile, they speed up their research on extracting volatile oil and the ingredients.

  11. Alternative Asymmetric Stochastic Volatility Models

    NARCIS (Netherlands)

    M. Asai (Manabu); M.J. McAleer (Michael)

    2010-01-01

    textabstractThe stochastic volatility model usually incorporates asymmetric effects by introducing the negative correlation between the innovations in returns and volatility. In this paper, we propose a new asymmetric stochastic volatility model, based on the leverage and size effects. The model is

  12. Essays on nonparametric econometrics of stochastic volatility

    NARCIS (Netherlands)

    Zu, Y.

    2012-01-01

    Volatility is a concept that describes the variation of financial returns. Measuring and modelling volatility dynamics is an important aspect of financial econometrics. This thesis is concerned with nonparametric approaches to volatility measurement and volatility model validation.

  13. Impact of Gamma Radiation on Sex Pheromone Gland of Female and Male Response of Ephestia calidella (Guen.)

    International Nuclear Information System (INIS)

    Hazaa, M.A.M.; Alm El-Din, M. M. S.; Mikhaiel, A.A.

    2012-01-01

    The sex pheromone gland of female oases date moth, Ephestia calidella is located inter segmentally between eight and nine abdominal segment. Effect of three sub sterilizing doses 75, 100 and 125 Gy of gamma radiation on pheromone production and on male response were studied. The results obtained revealed that gamma irradiation reduce the pheromone production by female and the responsiveness of male. The effect was increased by increasing the radiation dose. Histological studies of pheromone gland also, indicated that gamma irradiation disturb epithelial cells of the gland and becoming thin at certain parts. Also, gland hairs ruptured or completely disappeared at the highest dose of 125 Gy.

  14. Larval salivary glands are a source of primer and releaser pheromone in honey bee ( Apis mellifera L.)

    Science.gov (United States)

    Conte, Yves Le; Bécard, Jean-Marc; Costagliola, Guy; de Vaublanc, Gérard; Maâtaoui, Mohamed El; Crauser, Didier; Plettner, Erika; Slessor, Keith N.

    2006-05-01

    A brood pheromone identified in honeybee larvae has primer and releaser pheromone effects on adult bees. Using gas chromatography-mass spectrometry (GC-MS) to evaluate fatty acid esters—the pheromonal compounds—in different parts of the larvae, we have localized the source of the esters as the larval salivary glands. A histochemical study describes the glands and confirms the presence of lipids in the glands. Epithelial cells of the gland likely secrete the fatty acids into the lumen of the gland. These results demonstrate the salivary glands to be a reservoir of esters, components of brood pheromone, in honeybee larvae.

  15. Volatile metabolites from actinomycetes

    DEFF Research Database (Denmark)

    Scholler, C.E.G.; Gurtler, H.; Pedersen, R.

    2002-01-01

    Twenty-six Streptomyces spp. were screened for their volatile production capacity on yeast starch agar. The volatile organic compounds (VOCs) were concentrated on a porous polymer throughout an 8-day growth period. VOCs were analyzed by gas chromatography with flame ionization detection...... and identified or characterized by gas chromatography-mass spectrometry. A total of 120 VOCs were characterized by retention index and mass spectra. Fifty-three compounds were characterized as terpenoid compounds, among which 18 could be identified. Among the VOCs were alkanes, alkenes, alcohols, esters, ketones....... The relationship between the excretion of geosmin and the production of spores was examined for one isolate. A good correlation between headspace geosmin and the number of spores was observed, suggesting that VOCs could be used to indicate the activity of these microorganisms in heterogeneous substrates....

  16. Minimum Tracking Error Volatility

    OpenAIRE

    Luca RICCETTI

    2010-01-01

    Investors assign part of their funds to asset managers that are given the task of beating a benchmark. The risk management department usually imposes a maximum value of the tracking error volatility (TEV) in order to keep the risk of the portfolio near to that of the selected benchmark. However, risk management does not establish a rule on TEV which enables us to understand whether the asset manager is really active or not and, in practice, asset managers sometimes follow passively the corres...

  17. Recovering volatile liquids

    Energy Technology Data Exchange (ETDEWEB)

    Bregeat, J H

    1925-07-30

    The products of hydrogenation of alicyclic compounds, such as terpenes, for example, pinene or oil of turpentine, are used as washing liquids for absorbing vapours of volatile liquids from gases, such as natural gases from petroliferous regions, gases from the distillation of coal, lignite, schist, peat, etc. or from the cracking of heavy oils. Other liquids such as tar oils vaseline oils, cresols, etc. may be added.

  18. Understanding Interest Rate Volatility

    OpenAIRE

    Volker, Desi

    2016-01-01

    This thesis is the result of my Ph.D. studies at the Department of Finance of the Copenhagen Business School. It consists of three essays covering topics related to the term structure of interest rates, monetary policy and interest rate volatility. The rst essay, \\Monetary Policy Uncertainty and Interest Rates", examines the role of monetary policy uncertainty on the term structure of interest rates. The second essay, \\A Regime-Switching A ne Term Structure Model with Stochast...

  19. Silicon isotopes in angrites and volatile loss in planetesimals

    Science.gov (United States)

    Moynier, Frédéric; Savage, Paul S.; Badro, James; Barrat, Jean-Alix

    2014-01-01

    Inner solar system bodies, including the Earth, Moon, and asteroids, are depleted in volatile elements relative to chondrites. Hypotheses for this volatile element depletion include incomplete condensation from the solar nebula and volatile loss during energetic impacts. These processes are expected to each produce characteristic stable isotope signatures. However, processes of planetary differentiation may also modify the isotopic composition of geochemical reservoirs. Angrites are rare meteorites that crystallized only a few million years after calcium–aluminum-rich inclusions and exhibit extreme depletions in volatile elements relative to chondrites, making them ideal samples with which to study volatile element depletion in the early solar system. Here we present high-precision Si isotope data that show angrites are enriched in the heavy isotopes of Si relative to chondritic meteorites by 50–100 ppm/amu. Silicon is sufficiently volatile such that it may be isotopically fractionated during incomplete condensation or evaporative mass loss, but theoretical calculations and experimental results also predict isotope fractionation under specific conditions of metal–silicate differentiation. We show that the Si isotope composition of angrites cannot be explained by any plausible core formation scenario, but rather reflects isotope fractionation during impact-induced evaporation. Our results indicate planetesimals initially formed from volatile-rich material and were subsequently depleted in volatile elements during accretion. PMID:25404309

  20. The memory of volatility

    Directory of Open Access Journals (Sweden)

    Kai R. Wenger

    2018-03-01

    Full Text Available The focus of the volatility literature on forecasting and the predominance of theconceptually simpler HAR model over long memory stochastic volatility models has led to the factthat the actual degree of memory estimates has rarely been considered. Estimates in the literaturerange roughly between 0.4 and 0.6 - that is from the higher stationary to the lower non-stationaryregion. This difference, however, has important practical implications - such as the existence or nonexistenceof the fourth moment of the return distribution. Inference on the memory order is complicatedby the presence of measurement error in realized volatility and the potential of spurious long memory.In this paper we provide a comprehensive analysis of the memory in variances of international stockindices and exchange rates. On the one hand, we find that the variance of exchange rates is subject tospurious long memory and the true memory parameter is in the higher stationary range. Stock indexvariances, on the other hand, are free of low frequency contaminations and the memory is in the lowernon-stationary range. These results are obtained using state of the art local Whittle methods that allowconsistent estimation in presence of perturbations or low frequency contaminations.

  1. The antibacterial protein lysozyme identified as the termite egg recognition pheromone.

    Directory of Open Access Journals (Sweden)

    Kenji Matsuura

    Full Text Available Social insects rely heavily on pheromone communication to maintain their sociality. Egg protection is one of the most fundamental social behaviours in social insects. The recent discovery of the termite-egg mimicking fungus 'termite-ball' and subsequent studies on termite egg protection behaviour have shown that termites can be manipulated by using the termite egg recognition pheromone (TERP, which strongly evokes the egg-carrying and -grooming behaviours of workers. Despite the great scientific and economic importance, TERP has not been identified because of practical difficulties. Herein we identified the antibacterial protein lysozyme as the TERP. We isolated the target protein using ion-exchange and hydrophobic interaction chromatography, and the MALDI-TOF MS analysis showed a molecular size of 14.5 kDa. We found that the TERP provided antibacterial activity against a gram-positive bacterium. Among the currently known antimicrobial proteins, the molecular size of 14.5 kDa limits the target to lysozyme. Termite lysozymes obtained from eggs and salivary glands, and even hen egg lysozyme, showed a strong termite egg recognition activity. Besides eggs themselves, workers also supply lysozyme to eggs through frequent egg-grooming, by which egg surfaces are coated with saliva containing lysozyme. Reverse transcript PCR analysis showed that mRNA of termite lysozyme was expressed in both salivary glands and eggs. Western blot analysis confirmed that lysozyme production begins in immature eggs in queen ovaries. This is the first identification of proteinaceous pheromone in social insects. Researchers have focused almost exclusively on hydrocarbons when searching for recognition pheromones in social insects. The present finding of a proteinaceous pheromone represents a major step forward in, and result in the broadening of, the search for recognition pheromones. This novel function of lysozyme as a termite pheromone illuminates the profound influence

  2. Monitoring Pseudococcus calceolariae (Hemiptera: Pseudococcidae) in Fruit Crops Using Pheromone-Baited Traps.

    Science.gov (United States)

    Flores, M Fernanda; Romero, Alda; Oyarzun, M Soledad; Bergmann, Jan; Zaviezo, Tania

    2015-10-01

    The citrophilus mealybug, Pseudococcus calceolariae (Maskell), is an important pest of fruit crops in many regions of the world. Recently, its sex pheromone has been identified and synthesized. We carried out field experiments with the goal of developing monitoring protocols for P. calceolariae using pheromone-baited traps. Traps checked hourly for 24 hours showed a distinct diel pattern of male flight, between 18:00 and 21:00 h. The presence of unnatural stereoisomers did not affect trap captures, with isomeric mixtures capturing similar amounts of males as the biological active isomer. Dose of isomeric mixture pheromone (0-100 µg) had a nonlinear effect on male captures, with 10, 30, and 50 µg capturing similar amounts. The effective range of pheromone traps was determined by placing traps at different distances (15, 40, and 80 m) from an infested blueberry field, loaded with 0, 1 and 25 µg of the pheromone. For all distances, 25 µg dose captured more males, and was highly attractive up to 40 m. There was a significant effect of lure age on male captures (0-150 d), with similar amount of males captured up to 90-day-old lure, and lower captures in the 150-day-old lure compared with fresh ones. We found significant positive correlations between P. calceolariae males caught in pheromone traps with female abundance and fruit infestation at harvest. Our results show the usefulness of P. calceolariae pheromones for monitoring at field level and provide information for the design of monitoring protocols. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Functional characterization of sex pheromone receptors in the purple stem borer, Sesamia inferens (Walker).

    Science.gov (United States)

    Zhang, Y-N; Zhang, J; Yan, S-W; Chang, H-T; Liu, Y; Wang, G-R; Dong, S-L

    2014-10-01

    The sex pheromone communication system in moths is highly species-specific and extremely sensitive, and pheromone receptors (PRs) are thought to be the most important factors in males. In the present study, three full-length cDNAs encoding PRs were characterized from Sesamia inferens antennae. These three PRs were all male-specific in expression, but their relative expression levels were very different; SinfOR29 was 17- to 23-fold higher than the other two PRs. Phylogenetic and motif pattern analyses showed that these three PRs were allocated to different PR subfamilies with different motif patterns. Functional analysis using the heterologous expression system of Xenopus oocytes demonstrated that SinfOR29 specifically and sensitively responded to the major pheromone component, Z11-16:OAc [concentration for 50% of maximal effect (EC50 ) = 3.431 × 10(-7) M], while SinfOR21 responded robustly to a minor pheromone component Z11-16:OH (EC50  = 1.087 × 10(-6) M). SinfOR27, however, displayed no response to any of the three pheromone components, but, interestingly, it was sensitive to a non-sex pheromone component Z9,E12-14:OAc (EC50  = 1.522 × 10(-6) M). Our results provide insight into the molecular mechanisms of specificity and sensitivity of the sex pheromone communication system in moths. © 2014 The Royal Entomological Society.

  4. Representation of pheromones, interspecific signals, and plant odors in higher olfactory centers; mapping physiologically identified antennal-lobe projection neurons in the male heliothine moth

    Directory of Open Access Journals (Sweden)

    Xin-Cheng eZhao

    2014-10-01

    Full Text Available In the primary olfactory centre of the moth brain, for example, a few enlarged glomeruli situated dorsally, at the entrance of the antennal nerve, are devoted to information about female-produced substances whereas a set of more numerous ordinary glomeruli receives input about general odorants. Heliothine moths are particularly suitable for studying central chemosensory mechanisms not only because of their anatomically separated systems for plant odours and pheromones but also due to their use of female-produced substances in communication across the species. Thus, the male-specific system of heliothine moths includes two sub arrangements, one ensuring attraction and mating behavior by carrying information about pheromones released by conspecifics, and the other reproductive isolation via signal information emitted from heterospecifics. Based on previous tracing experiments, a general chemotopic organization of the male-specific glomeruli has been demonstrated in a number of heliothine species. As compared to the well explored organization of the moth antennal lobe, demonstrating a non-overlapping representation of the biologically relevant stimuli, less is known about the neural arrangement residing at the following synaptic level, i.e. the mushroom body calyces and the lateral horn. In the study presented here, we have labelled physiologically characterized antennal-lobe projection neurons in males of the two heliothine species, Heliothis virescens and Helicoverpa assulta, for the purpose of mapping their target regions in the protocerebrum. In order to compare the representation of plant odours, pheromones, and interspecific signals in the higher brain regions of each species, we have created standard brain atlases and registered three-dimensional models of distinct uniglomerular projection neuron types into the relevant atlas.

  5. The Pricing of Options on Assets with Stochastic Volatilities.

    OpenAIRE

    Hull, John C; White, Alan D

    1987-01-01

    One option-pricing problem which has hitherto been unsolved is the pricing of European call on an asset which has a stochastic volatility. This paper examines this problem. The option price is determined in series form for the case in which the stochastic volatility is independent of the stock price. Numerical solutions are also produced for the case in which the volatility is correlated with the stock price. It is found that the Black-Scholes price frequently overprices options and that the ...

  6. Functional evolution of a multigene family: orthologous and paralogous pheromone receptor genes in the turnip moth, Agrotis segetum.

    Directory of Open Access Journals (Sweden)

    Dan-Dan Zhang

    Full Text Available Lepidopteran pheromone receptors (PRs, for which orthologies are evident among closely related species, provide an intriguing example of gene family evolution in terms of how new functions may arise. However, only a limited number of PRs have been functionally characterized so far and thus evolutionary scenarios suffer from elements of speculation. In this study we investigated the turnip moth Agrotis segetum, in which female moths produce a mixture of chemically related pheromone components that elicit specific responses from receptor cells on male antennae. We cloned nine A. segetum PR genes and the Orco gene by degenerate primer based RT-PCR. The nine PR genes, named as AsegOR1 and AsegOR3-10, fall into four distinct orthologous clusters of known lepidopteran PRs, of which one contains six paralogues. The paralogues are under relaxed selective pressure, contrasting with the purifying selection on other clusters. We identified the receptors AsegOR9, AsegOR4 and AsegOR5, specific for the respective homologous pheromone components (Z-5-decenyl, (Z-7-dodecenyl and (Z-9-tetradecenyl acetates, by two-electrode voltage clamp recording from Xenopus laevis oocytes co-expressing Orco and each PR candidate. These receptors occur in three different orthologous clusters. We also found that the six paralogues with high sequence similarity vary dramatically in ligand selectivity and sensitivity. Different from AsegOR9, AsegOR6 showed a relatively large response to the behavioural antagonist (Z-5-decenol, and a small response to (Z-5-decenyl acetate. AsegOR1 was broadly tuned, but most responsive to (Z-5-decenyl acetate, (Z-7-dodecenyl acetate and the behavioural antagonist (Z-8-dodecenyl acetate. AsegOR8 and AsegOR7, which differ from AsegOR6 and AsegOR1 by 7 and 10 aa respectively, showed much lower sensitivities. AsegOR10 showed only small responses to all the tested compounds. These results suggest that new receptors arise through gene duplication, and

  7. PERUBAHAN KOMPONEN VOLATIL SELAMA FERMENTASI KECAP [Change Volatile Components During Soy Sauce Fermentation

    Directory of Open Access Journals (Sweden)

    Anton Apriyantono1

    2004-08-01

    Full Text Available A study has been conducted to investigate changes of volatile components during soy sauce fermentation. During the fermentation, many volatile components produced may contribute to soy sauce flavor. THe volatile identified by GC-MS werw classified into hydrocarbon (15, alcohol (15, aldehyde (14, ester (14, ketone (9, benzene derivative (11, fatty acid (9, furan (5, terpenoid (18, pyrazine (3, thiazole (1, pyridine (1 and sulfur containing compound (2.Concentration of compounds found in almost all fermentation steps, such as hexanal and benzaldehyde did. These compounds may be derived from raw soybean, since they were all present in raw soybean and their concentration did not change during fermentation. Concentration of palmitic acid and benzeneacetaldehyde, in general, increased during all fermentation steps. They are probably derived from lipid degradation or microorganism activities. Concentrations of some fatty acids, esters and hydrocarbons, such as linoleic acid, methyl palmitate and heptadecane increased during salt fermentation only. Concentration of some other compounds, such as 2,4 decadienal decreased or undetected during fermentation.The absence of some volatile compounds, e.g. (E-nerolidol and (E,E-famesol in boiled soybean which were previously present in raw soybean may be due to evaporation of these compounds during boiling. Some volatile compounds such as, methyl heptadecanoate and few aromatic alcohols are likely derived from Aspergillus sojae, since these compounds were identified only in 0 day koji

  8. Age-dependent plasticity of sex pheromone response in the moth, Agrotis ipsilon: combined effects of octopamine and juvenile hormone

    DEFF Research Database (Denmark)

    Jarriault, David; Barrozo, Romina B; de Carvalho Pinto, Carlos J

    2009-01-01

    Male moths use sex pheromones to find their mating partners. In the moth, Agrotis ipsilon, the behavioral response and the neuron sensitivity within the primary olfactory centre, the antennal lobe (AL), to sex pheromone increase with age and juvenile hormone (JH) biosynthesis. By manipulating...

  9. Mimicking Insect Communication: Release and Detection of Pheromone, Biosynthesized by an Alcohol Acetyl Transferase Immobilized in a Microreactor

    NARCIS (Netherlands)

    Munoz, L.; Dimov, N.G.; Carot-Sans, G.; Bula, W.P.; Guerrero, A.; Gardeniers, Johannes G.E.

    2012-01-01

    Infochemical production, release and detection of (Z,E)-9,11-tetradecadienyl acetate, the major component of the pheromone of the moth Spodoptera littoralis, is achieved in a novel microfluidic system designed to mimic the final step of the pheromone biosynthesis by immobilized recombinant alcohol

  10. Sampling gravid Culex quinquefasciatus (Diptera: Culicidae) in Tanzania with traps baited with synthetic oviposition pheromone and grass infusions

    NARCIS (Netherlands)

    Mboera, L.E.G.; Takken, W.; Mdira, K.Y.; Pickett, J.A.

    2000-01-01

    The effectiveness of traps baited with (5R,6S)-6-acetoxy-5-hexadecanolide (the synthetic oviposition pheromone) and grass infusions in sampling a population of gravid Culex quinquefasciatus Say was conducted in Muheza, Northeast Tanzania. A counterflow geometry (CFG) trap baited with pheromone and

  11. Intra-annual variation in responses by flying southern pine beetles (Coleoptera: Curculionidae: Scolytinae) to pheromone component endo-brevicomin

    Science.gov (United States)

    Brian T. Sullivan; Cavell Brownie; JoAnne P. Barrett

    2016-01-01

    The southern pine beetle Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae: Scolytinae) is attracted to an aggregation pheromone that includes the multifunctional pheromone component endobrevicomin. The effect of endo-brevicomin on attractive lures varies from strong enhancement to reduction of beetle attraction depending upon release rate, lure component...

  12. Evolution of moth sex pheromone composition by a single amino acid substitution in a fatty acid desaturase

    Czech Academy of Sciences Publication Activity Database

    Buček, Aleš; Matoušková, P.; Vogel, H.; Šebesta, Petr; Jahn, Ullrich; Weissflog, J.; Svatoš, Aleš; Pichová, Iva

    2015-01-01

    Roč. 112, č. 41 (2015), s. 12586-12591 ISSN 0027-8424 R&D Projects: GA MŠk LO1302 Institutional support: RVO:61388963 Keywords : fatty acid desaturase * Manduca sexta * sex pheromone biosynthesis * pheromone evolution * substrate specificity Subject RIV: CC - Organic Chemistry Impact factor: 9.423, year: 2015

  13. Gqalpha-linked PLCbeta and PLCgamma are essential components of the pheromone biosynthesis activating neuropeptide (PBAN) signal transduction cascade

    Science.gov (United States)

    Sex pheromone production for most moths is regulated by pheromone biosynthesis activating neuropeptide (PBAN). In Bombyx mori, PBAN binding triggers the opening of store-operated Ca2+ channels, suggesting the involvement of a receptor-activated phospholipase C (PLC). In this study, we found that P...

  14. Gβ promotes pheromone receptor polarization and yeast chemotropism by inhibiting receptor phosphorylation.

    Science.gov (United States)

    Ismael, Amber; Tian, Wei; Waszczak, Nicholas; Wang, Xin; Cao, Youfang; Suchkov, Dmitry; Bar, Eli; Metodiev, Metodi V; Liang, Jie; Arkowitz, Robert A; Stone, David E

    2016-04-12

    Gradient-directed cell migration (chemotaxis) and growth (chemotropism) are processes that are essential to the development and life cycles of all species. Cells use surface receptors to sense the shallow chemical gradients that elicit chemotaxis and chemotropism. Slight asymmetries in receptor activation are amplified by downstream signaling systems, which ultimately induce dynamic reorganization of the cytoskeleton. During the mating response of budding yeast, a model chemotropic system, the pheromone receptors on the plasma membrane polarize to the side of the cell closest to the stimulus. Although receptor polarization occurs before and independently of actin cable-dependent delivery of vesicles to the plasma membrane (directed secretion), it requires receptor internalization. Phosphorylation of pheromone receptors by yeast casein kinase 1 or 2 (Yck1/2) stimulates their internalization. We showed that the pheromone-responsive Gβγ dimer promotes the polarization of the pheromone receptor by interacting with Yck1/2 and locally inhibiting receptor phosphorylation. We also found that receptor phosphorylation is essential for chemotropism, independently of its role in inducing receptor internalization. A mathematical model supports the idea that the interaction between Gβγ and Yck1/2 results in differential phosphorylation and internalization of the pheromone receptor and accounts for its polarization before the initiation of directed secretion. Copyright © 2016, American Association for the Advancement of Science.

  15. Multiphasic on/off pheromone signalling in moths as neural correlates of a search strategy.

    Directory of Open Access Journals (Sweden)

    Dominique Martinez

    Full Text Available Insects and robots searching for odour sources in turbulent plumes face the same problem: the random nature of mixing causes fluctuations and intermittency in perception. Pheromone-tracking male moths appear to deal with discontinuous flows of information by surging upwind, upon sensing a pheromone patch, and casting crosswind, upon losing the plume. Using a combination of neurophysiological recordings, computational modelling and experiments with a cyborg, we propose a neuronal mechanism that promotes a behavioural switch between surge and casting. We show how multiphasic On/Off pheromone-sensitive neurons may guide action selection based on signalling presence or loss of the pheromone. A Hodgkin-Huxley-type neuron model with a small-conductance calcium-activated potassium (SK channel reproduces physiological On/Off responses. Using this model as a command neuron and the antennae of tethered moths as pheromone sensors, we demonstrate the efficiency of multiphasic patterning in driving a robotic searcher toward the source. Taken together, our results suggest that multiphasic On/Off responses may mediate olfactory navigation and that SK channels may account for these responses.

  16. Multiphasic on/off pheromone signalling in moths as neural correlates of a search strategy.

    Science.gov (United States)

    Martinez, Dominique; Chaffiol, Antoine; Voges, Nicole; Gu, Yuqiao; Anton, Sylvia; Rospars, Jean-Pierre; Lucas, Philippe

    2013-01-01

    Insects and robots searching for odour sources in turbulent plumes face the same problem: the random nature of mixing causes fluctuations and intermittency in perception. Pheromone-tracking male moths appear to deal with discontinuous flows of information by surging upwind, upon sensing a pheromone patch, and casting crosswind, upon losing the plume. Using a combination of neurophysiological recordings, computational modelling and experiments with a cyborg, we propose a neuronal mechanism that promotes a behavioural switch between surge and casting. We show how multiphasic On/Off pheromone-sensitive neurons may guide action selection based on signalling presence or loss of the pheromone. A Hodgkin-Huxley-type neuron model with a small-conductance calcium-activated potassium (SK) channel reproduces physiological On/Off responses. Using this model as a command neuron and the antennae of tethered moths as pheromone sensors, we demonstrate the efficiency of multiphasic patterning in driving a robotic searcher toward the source. Taken together, our results suggest that multiphasic On/Off responses may mediate olfactory navigation and that SK channels may account for these responses.

  17. Sublethal Effects of Neonicotinoid Insecticide on Calling Behavior and Pheromone Production of Tortricid Moths.

    Science.gov (United States)

    Navarro-Roldán, Miguel A; Gemeno, César

    2017-09-01

    In moths, sexual behavior combines female sex pheromone production and calling behavior. The normal functioning of these periodic events requires an intact nervous system. Neurotoxic insecticide residues in the agroecosystem could impact the normal functioning of pheromone communication through alteration of the nervous system. In this study we assess whether sublethal concentrations of the neonicotinoid insecticide thiacloprid, that competitively modulates nicotinic acetylcholine receptors at the dendrite, affect pheromone production and calling behavior in adults of three economically important tortricid moth pests; Cydia pomonella (L.), Grapholita molesta (Busck), and Lobesia botrana (Denis & Schiffermüller). Thiacloprid significantly reduced the amount of calling in C. pomonella females at LC 0.001 (a lethal concentration that kills only 1 in 10 5 individuals), and altered its calling period at LC 1 , and in both cases the effect was dose-dependent. In the other two species the effect was similar but started at higher LCs, and the effect was relatively small in L. botrana. Pheromone production was altered only in C. pomonella, with a reduction of the major compound, codlemone, and one minor component, starting at LC 10 . Since sex pheromones and neonicotinoids are used together in the management of these three species, our results could have implications regarding the interaction between these two pest control methods.

  18. Mixtures of Two Bile Alcohol Sulfates Function as a Proximity Pheromone in Sea Lamprey.

    Directory of Open Access Journals (Sweden)

    Cory O Brant

    Full Text Available Unique mixtures of pheromone components are commonly identified in insects, and have been shown to increase attractiveness towards conspecifics when reconstructed at the natural ratio released by the signaler. In previous field studies of pheromones that attract female sea lamprey (Petromyzon marinus, L., putative components of the male-released mating pheromone included the newly described bile alcohol 3,12-diketo-4,6-petromyzonene-24-sulfate (DkPES and the well characterized 3-keto petromyzonol sulfate (3kPZS. Here, we show chemical evidence that unequivocally confirms the elucidated structure of DkPES, electrophysiological evidence that each component is independently detected by the olfactory epithelium, and behavioral evidence that mature female sea lamprey prefer artificial nests activated with a mixture that reconstructs the male-released component ratio of 30:1 (3kPZS:DkPES, molar:molar. In addition, we characterize search behavior (sinuosity of swim paths of females approaching ratio treatment sources. These results suggest unique pheromone ratios may underlie reproductive isolating mechanisms in vertebrates, as well as provide utility in pheromone-integrated control of invasive sea lamprey in the Great Lakes.

  19. Courtship Pheromone Use in a Model Urodele, the Mexican Axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Maex, Margo; Van Bocxlaer, Ines; Mortier, Anneleen; Proost, Paul; Bossuyt, Franky

    2016-02-04

    Sex pheromones have been shown to constitute a crucial aspect of salamander reproduction. Until now, courtship pheromones of Salamandridae and Plethodontidae have been intensively studied, but information on chemical communication in other urodelan families is essentially lacking. The axolotl (Ambystoma mexicanum, Ambystomatidae) has a courtship display that suggests a key role for chemical communication in the orchestration of its sexual behavior, but no sex pheromones have yet been characterized from this species. Here we combined whole transcriptome analyses of the male cloaca with proteomic analyses of water in which axolotls were allowed to court to show that male axolotls secrete multiple ca. 20 kDa glycosylated sodefrin precursor-like factor (SPF) proteins during courtship. In combination with phylogenetic analyses, our data show that the male cloaca essentially secretes a courtship-specific clade of SPF proteins that is orthologous to salamandrid courtship pheromones. In addition, we identified an SPF protein for which no orthologs have been described from other salamanders so far. Overall, our study advocates a central role for SPF proteins during the courtship display of axolotls and adds knowledge on pheromone use in a previously unexplored deep evolutionary branch of salamander evolution.

  20. THE USE OF GRIGNARD REAGENT IN PHEROMONE SYNTHESIS FOR PALM WEEVIL (Rhynchorus, Sp

    Directory of Open Access Journals (Sweden)

    Warsito Warsito

    2010-06-01

    Full Text Available In an integrated controlling system of palm weevil, using of synthetic feromoid is strickly needed. The research is aimed to synthesize pheromone which secreted by the weevil, e.g. 4-methyl-5-nonanol (R. ferrugineus and 3-methyl-4-octanol (R. schach through Grignard reagent which formed in situ. The synthesis was proceded by retrosynthesis to determine the precursor, valeraldehyde. The precursor was reacted with Grignard reagent of sec-amyl magnesium bromide (R. ferrugenieus and sec-butyl magnesium bromide (R. shach which made in situ. Characterization of the synthetic molecular pheromone was performed by Gas Chromatography-mass spectroscopy and Fourier Transformed Infra Red. The bioassay of the molecule was carried out by olfactometer. The result showed that the conversion of the reactions were 51.28% (4-methyl-5-nonanol and 85.90% (3-methyl-4-octanol. The character of physico-chemical and bioactivity of the synthetic pheromone are identic with natural pheromones.   Keywords: palm weevil, pheromone, grignard reagent