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1.
Aquat Toxicol ; 227: 105591, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32853898

RESUMO

The effects of allelopathy and the potential harm of several isolated allelochemicals have been studied in detail. Microorganisms in the phycosphere play an important role in algal growth, decay and nutrient cycling. However, it is unknown and often neglected whether allelochemicals affect the phycosphere. The present study selected a phenolic acid protocatechuic acid (PA) - previously shown to be an allelochemical. We studied PA at a half maximal effective concentration of 0.20 mM (30 mg L-1) against Scrippsiella trochoidea to assess the effect of PA on its phycosphere in an acute time period (48 h). The results showed that: 1) OTUs (operational taxonomic units) in the treatment groups (31.4 ± 0.55) exceeded those of the control groups (28.2 ± 1.30) and the Shannon and Simpson indices were lower than the control groups (3.31 ± 0.08 and 0.84 ± 0.02, 3.45 ± 0.09 and 0.88 ± 0.01); 2) Gammaproteobacteria predominated in the treatment groups (44.71 ± 2.13 %) while Alphaproteobacteria dominated in the controls (67.17 ± 3.87 %); 3) Gammaproteobacteria and Alphaproteobacteria were important biomarkers in the treatment and control groups respectively (LDA > 4.0). PA improved the relative abundance of Alteromonas significantly and decreased the one of Rhodobacteraceae. PICRUSt analysis showed that the decrease of Rhodobacterceae was closely related with the decline of most functional genes in metabolism such as amino acid, carbohydrate, xenobiotics, cofactors and vitamins metabolism after PA-treated.


Assuntos
Alelopatia/efeitos dos fármacos , Dinoflagelados/efeitos dos fármacos , Proliferação Nociva de Algas/efeitos dos fármacos , Hidroxibenzoatos/farmacologia , Microbiota/efeitos dos fármacos , Feromônios/farmacologia , Alelopatia/genética , Bacteroidetes/efeitos dos fármacos , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Dinoflagelados/genética , Dinoflagelados/crescimento & desenvolvimento , Microbiota/genética , Proteobactérias/efeitos dos fármacos , Proteobactérias/genética , Proteobactérias/isolamento & purificação
2.
Nature ; 584(7822): 584-588, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32788724

RESUMO

Locust plagues threaten agricultural and environmental safety throughout the world1,2. Aggregation pheromones have a crucial role in the transition of locusts from a solitary form to the devastating gregarious form and the formation of large-scale swarms3,4. However, none of the candidate compounds reported5-7 meet all the criteria for a locust aggregation pheromone. Here, using behavioural assays, electrophysiological recording, olfactory receptor characterization and field experiments, we demonstrate that 4-vinylanisole (4VA) (also known as 4-methoxystyrene) is an aggregation pheromone of the migratory locust (Locusta migratoria). Both gregarious and solitary locusts are strongly attracted to 4VA, regardless of age and sex. Although it is emitted specifically by gregarious locusts, 4VA production can be triggered by aggregation of four to five solitary locusts. It elicits responses specifically from basiconic sensilla on locust antennae. We also identified OR35 as a specific olfactory receptor of 4VA. Knockout of OR35 using CRISPR-Cas9 markedly reduced the electrophysiological responses of the antennae and impaired 4VA behavioural attractiveness. Finally, field trapping experiments verified the attractiveness of 4VA to experimental and wild populations. These findings identify a locust aggregation pheromone and provide insights for the development of novel control strategies for locusts.


Assuntos
Locusta migratoria/efeitos dos fármacos , Locusta migratoria/fisiologia , Feromônios/metabolismo , Feromônios/farmacologia , Estirenos/metabolismo , Estirenos/farmacologia , Envelhecimento , Migração Animal/efeitos dos fármacos , Animais , Ecossistema , Feminino , Controle de Insetos , Locusta migratoria/química , Masculino , Densidade Demográfica , Receptores Odorantes/deficiência , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Sensilas/fisiologia
3.
Chem Biol Interact ; 325: 109123, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32387439

RESUMO

To avoid being preyed, organisms must be able to identify predatory threats by sensing molecules released by predators (kairomones), and to employ effective strategies to prevent detection by predators. Furthermore, in the wild, organisms are also exposed to chemicals that may alter their behavioral traits, such as neuroactive pharmaceuticals. Considering the co-occurrence of both types of chemicals, their possible interaction needs to be studied. To address this topic, the aim of this study was to verify the effects of fish kairomone (FK - a chemical associated to putative predation by fish) and chlorpromazine (CPZ - neuroactive pharmaceutical drug, environmental contaminant), isolated and in combination, in different functional endpoints of Daphnia magna, such as oxygen consumption, feeding rate, behavior and reproduction. Among these endpoints, oxygen consumption was only affected by the combination of compounds (FK + CPZ). On the other hand, feeding rate was affected by all treatments, being lower than control. For life history traits and phototactic behavior, the effects of FK predominated over the ones caused by CPZ exposure, incrementing the reproductive output of females, leading to greater population growth rates and increasing negative phototactic behaviour.


Assuntos
Clorpromazina/toxicidade , Daphnia/efeitos dos fármacos , Peixes/metabolismo , Feromônios/farmacologia , Poluentes Químicos da Água/toxicidade , Animais , Comportamento Animal/efeitos dos fármacos , Daphnia/fisiologia , Interações Medicamentosas , Feromônios/metabolismo , Reprodução/efeitos dos fármacos
4.
Bull Entomol Res ; 110(5): 638-644, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32381143

RESUMO

Telenomus podisi Ashmead (Hymenoptera: Scelionidae) is the most important egg parasitoid of Euschistus heros (Fabricius) (Hemiptera: Pentatomidae), and its successful parasitism is related to their searching ability to find suitable hosts under a complex chemical environment using host-reliable cues. Thus, the objective of this study was to elucidate chemical substances on the external layer of E. heros eggs and report its potential kairomonal activity on T. podisi. We tested female wasps in olfactometer system to synthetic compounds obtained from a chemical identification of E. heros egg masses. The synthetic blend was also evaluated in parasitism tests under laboratory and semi-field conditions. We identified 31 substances from egg surface extracts, including monoterpenes, aldehydes and alkanes. Among those compounds, a synthetic solution including camphene, ß-pinene, limonene and benzaldehyde-induced chemotaxic behaviour on the wasps and increased the parasitism on E. heros eggs, either in laboratory or semi-field test, suggesting its potential use to T. podisi manipulation and parasitism improvement.


Assuntos
Heterópteros/química , Óvulo/química , Feromônios/farmacologia , Vespas/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Feminino , Heterópteros/parasitologia , Óvulo/parasitologia
5.
Lett Appl Microbiol ; 71(1): 39-45, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32390273

RESUMO

Filter feeding is a biotic process that brings waterborne bacteria in close contact with each other and may thus support the horizontal transfer of their antimicrobial resistance genes. This laboratory study investigated whether the freshwater sponge Ephydatia fluviatilis supported the transfer of vancomycin resistance between two Enterococcus faecalis strains that we previously demonstrated to exhibit pheromone responsive plasmid conjugation. Microcosm experiments exposed live and dead colonies of laboratory-grown sponges to a vancomycin-resistant donor strain and a rifampicin-resistant recipient strain of Ent. faecalis. Enterococci with both resistance phenotypes were detected on double selection plates. In comparison to controls, abundance of these presumed transconjugants increased significantly in water from sponge microcosms. Homogenized suspensions of sponge cells also yielded presumed transconjugants; however, there was no significant difference between samples from live or dead sponges. Fluorescent in situ hybridization analysis of the sponge cell matrix using species-specific probes revealed the presence of enterococci clusters with cells adjacent to each other. The results demonstrated that sponge colonies can support the horizontal transfer of antimicrobial resistance although the mechanism underlying this process, such as binding of the bacteria to the sponge collagen matrix, has yet to be fully elucidated.


Assuntos
Antibacterianos/farmacologia , Conjugação Genética/genética , Farmacorresistência Bacteriana/genética , Enterococcus faecalis/genética , Poríferos/microbiologia , Resistência a Vancomicina/genética , Animais , Enterococcus faecalis/efeitos dos fármacos , Água Doce , Hibridização in Situ Fluorescente , Feromônios/farmacologia , Plasmídeos/genética , Vancomicina/farmacologia
6.
Nat Microbiol ; 5(6): 821-829, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32251369

RESUMO

Volatile compounds emitted by bacteria are often sensed by other organisms as odours, but their ecological roles are poorly understood1,2. Well-known examples are the soil-smelling terpenoids geosmin and 2-methylisoborneol (2-MIB)3,4, which humans and various animals sense at extremely low concentrations5,6. The conservation of geosmin biosynthesis genes among virtually all species of Streptomyces bacteria (and genes for the biosynthesis of 2-MIB in about 50%)7,8, suggests that the volatiles provide a selective advantage for these soil microbes. We show, in the present study, that these volatiles mediate interactions of apparent mutual benefit between streptomycetes and springtails (Collembola). In field experiments, springtails were attracted to odours emitted by Streptomyces colonies. Geosmin and 2-MIB in these odours induce electrophysiological responses in the antennae of the model springtail Folsomia candida, which is also attracted to both compounds. Moreover, the genes for geosmin and 2-MIB synthases are under the direct control of sporulation-specific transcription factors, constraining emission of the odorants to sporulating colonies. F. candida feeds on the Streptomyces colonies and disseminates spores both via faecal pellets and through adherence to its hydrophobic cuticle. The results indicate that geosmin and 2-MIB production is an integral part of the sporulation process, completing the Streptomyces life cycle by facilitating dispersal of spores by soil arthropods.


Assuntos
Artrópodes/microbiologia , Canfanos/farmacologia , Naftóis/farmacologia , Feromônios/farmacologia , Solo/parasitologia , Esporos Bacterianos , Streptomyces , Animais
7.
PLoS Negl Trop Dis ; 14(3): e0007719, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32126087

RESUMO

The putative vector of trachoma, Musca sorbens, prefers to lay its eggs on human faeces on the ground. This study sought to determine whether M. sorbens females were attracted to volatile odours from human faeces in preference to odours from the faeces of other animals, and to determine whether specific volatile semiochemicals mediate selection of the faeces. Traps baited with the faeces of humans and local domestic animals were used to catch flies at two trachoma-endemic locations in The Gambia and one in Ethiopia. At all locations, traps baited with faeces caught more female M. sorbens than control traps baited with soil, and human faeces was the most successful bait compared with soil (mean rate ratios 44.40, 61.40, 10.50 [P<0.001]; 8.17 for child faeces [P = 0.004]). Odours from human faeces were sampled by air entrainment, then extracts of the volatiles were tested by coupled gas chromatography-electroantennography with laboratory-reared female M. sorbens. Twelve compounds were electrophysiologically active and tentatively identified by coupled mass spectrometry-gas chromatography, these included cresol, indole, 2-methylpropanoic acid, butanoic acid, pentanoic acid and hexanoic acid. It is possible that some of these volatiles govern the strong attraction of M. sorbens flies to human faeces. If so, a synthetic blend of these chemicals, at the correct ratios, may prove to be a highly attractive lure. This could be used in odour-baited traps for monitoring or control of this species in trachoma-endemic regions.


Assuntos
Fezes/química , Insetos Vetores/efeitos dos fármacos , Muscidae/efeitos dos fármacos , Feromônios/farmacologia , Compostos Orgânicos Voláteis/farmacologia , Adolescente , Adulto , Animais , Criança , Cromatografia Gasosa , Fenômenos Eletrofisiológicos , Etiópia , Feminino , Gâmbia , Humanos , Insetos Vetores/fisiologia , Masculino , Muscidae/fisiologia , Feromônios/isolamento & purificação , Compostos Orgânicos Voláteis/isolamento & purificação , Adulto Jovem
8.
Sci Rep ; 10(1): 2892, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-32076002

RESUMO

The pest species Spodoptera frugiperda, which is native to North and South America, has invaded Africa in 2016. The species consists of two strains, the corn-strain and rice-strain, which differ in their sexual communication. When we investigated populations from Benin and Nigeria, consisting of corn-strain and rice-corn-hybrid descendants, we found no strain-specific sexual communication differences. Both genotypes exhibited the same pheromone composition, consisting of around 97% (Z)-9-tetradecenyl acetate (Z9-14:Ac), 2% (Z)-7-dodecenyl acetate (Z7-12:Ac), and 1% (Z)-9-dodecenyl acetate (Z9-12:Ac), they had similar electrophysiological responses, and all mated around three hours into scotophase. However, we found geographic variation between African and American populations. The sex pheromone of African corn-strain and hybrid descendant females was similar to American rice-strain females and showed higher percentages of the male-attracting minor component Z7-12:Ac. In addition, African males exhibited the highest antennal sensitivity towards Z7-12:Ac, while American males showed highest sensitivity towards the major pheromone component Z9-14:Ac. Increasing the production of and response to the critical minor component Z7-12:Ac may reduce communication interference with other African Spodoptera species that share the same major pheromone component. The implications of our results on pheromone-based pest management strategies are discussed.


Assuntos
Adaptação Fisiológica , Espécies Introduzidas , Controle de Pragas , Comportamento Sexual Animal/fisiologia , Spodoptera/fisiologia , Adaptação Fisiológica/efeitos dos fármacos , África Ocidental , Animais , Antenas de Artrópodes/efeitos dos fármacos , Antenas de Artrópodes/fisiologia , Dodecanol/análogos & derivados , Dodecanol/farmacologia , Ácidos Graxos Monoinsaturados/farmacologia , Feminino , Masculino , Feromônios/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Spodoptera/efeitos dos fármacos , Spodoptera/genética , Zea mays
9.
Sci Rep ; 10(1): 3048, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-32080255

RESUMO

Mosquito-borne diseases like malaria are a major public health problem in tropical countries, such as Madagascar. Female Anopheles mosquito vectors the human malaria parasites (Plasmodium spp.) and is important indicator in malaria surveillance activities. Among the various means of vector control in Madagascar, the use of attractants for mass trapping of target species could be an alternative to insecticides. The aim of this study is to evaluate whether 4-hydroxycoumarin can be used as an attractant for anthropophilic Anopheles spp. vectors of malaria. For this, a field study was conducted using CDC light traps in the village of Ambohidray, Madagascar. 16 days of trapping was conducted and four replicates nights were performed for each product tested. 4-hydroxycoumarin, octenol and two types of blend of these products were tested. The results showed that 4-hydroxycoumarin (2 mg) have a significant attractive effect on Anopheles spp. and significant selectivity towards Anopheles gambiae s.l, and Anopheles mascarensis which are both significant malaria vectors in Madagascar. A synergy of 4-hydroxycoumarin with octenol was found to attract these mosquito vectors. A significant decrease in vector populations was observed during this experiment. These results suggest that 4-hydroxycoumarin could be useful for malaria surveillance and the control of vector populations.


Assuntos
4-Hidroxicumarinas/farmacologia , Anopheles/efeitos dos fármacos , Fatores Quimiotáticos/farmacologia , Malária/parasitologia , Mosquitos Vetores/parasitologia , Animais , Feminino , Geografia , Humanos , Umidade , Madagáscar , Controle de Mosquitos , Feromônios/farmacologia , Temperatura
10.
Vet Parasitol ; 278: 109036, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32004852

RESUMO

Amblyomma sculptum is a tick of medical-veterinary importance. Areas with high infestations need to be monitored, and parasitized hosts treated accordingly. Carbon dioxide (CO2) traps and acaricides are commonly deployed as control measures, although with some disadvantages such as high costs, challenging logistics and vertebrate intoxication. Semiochemicals have the potential to improve tick attraction to traps and monitoring devices and alleviate the burden of A. sculptum infestations. Four concentrations (10, 5, 2.5 and 1.25 %) of 13 semiochemical candidates (CO2 only at 5 % as the standard, benzaldehyde, benzoic acid, salicylic acid, 2,6 diclorophenol, R-limonene, S-limonene, methyl salicylate, 1-octen-3-ol, acetone, ammonium hydroxide, isobutyric acid and lactic acid) were tested on unfed A. sculptum nymphs and adults using a Y-tube olfactometer to evaluated repellence and attraction behaviors. All stages tested were attracted to CO2, whereas nymphs were repelled by benzaldehyde and R-limonene, both at 10 %, and isobutyric acid at 5 and 10 %. Nymphs were attracted by methyl salicylate, benzoic acid and salicylic acid, all at 1.25 %, and by ammonium hydroxide at 2.5 %. Males were attracted by benzoic acid at 2.5 %, while females were repelled by benzaldehyde at 5 %. Mixtures with the attractive compounds achieved no attraction response. The compounds that caused attractiveness in the olfactometer assay (CO2, methyl salicylate, benzoic acid, salicylic acid and ammonium hydroxide) were placed randomly in traps in a grassland plot naturally infested with A. sculptum in triplicate. Notably, dry ice (CO2) remained the best at luring ticks in the field (P < 0.001). Benzoic acid should be further investigated since attractant activity was strongly confirmed in both laboratory and field tests. On the other hand, isobutyric acid and R-limonene could be better exploited due to their repellent role revealed by the lab assay, which makes them worthwhile molecules as natural repellents for the management of this tick.


Assuntos
Repelentes de Insetos/farmacologia , Ixodidae/efeitos dos fármacos , Feromônios/farmacologia , Infestações por Carrapato/prevenção & controle , Animais
11.
J Econ Entomol ; 113(3): 1270-1278, 2020 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-31968098

RESUMO

The use of aerosol mating disruption for management of the navel orangeworm Amyelois transitella (Walker) in California tree nuts has increased markedly. This treatment suppresses pheromone monitoring traps in neighboring orchards as well as in the orchard under treatment. The current study, therefore, addresses the interrelated topics of which attractant is most effective, how the number of adults captured is affected by trap design, and what sex is captured. Under most circumstances, wing traps baited with phenyl propionate (PPO) captured more adults than those baited with a 5-compound kairomone blend. Adding a pheromone lure along with the dispenser for the experimental attractant increased the number of adults captured with PPO both in and near-mating disruption. In contrast, addition of a pheromone lure along with the kairomone blend only increased the number of adults captured in orchards near but not under mating disruption. Delta traps, which are preferred by the industry, captured fewer adults than wing traps. Improvements in the number of adults captured with PPO in delta traps from addition of a pheromone lure and from design modifications were additive. Both sexes were captured by all attractants and trap designs tested, and the sex ratio was highly variable. Open traps like the wing trap captured a slightly higher proportion of males than closed traps. These findings are discussed in the context of management of the navel orangeworm.


Assuntos
Mariposas , Atrativos Sexuais , Animais , Feminino , Controle de Insetos , Masculino , Feromônios/farmacologia , Reprodução , Atrativos Sexuais/farmacologia , Razão de Masculinidade , Comportamento Sexual Animal
12.
J Econ Entomol ; 113(3): 1290-1298, 2020 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-31971572

RESUMO

Mating disruption is used to help manage the navel orangeworm on approximately 200,000 ha of tree nut crops. Aerosol dispensers are the most common formulation, and all formulations use an incomplete pheromone blend consisting solely of (Z11,Z13)-hexadecadienal. Profile analysis (examination of capture and males in pheromone traps as a function of spatial density of dispensers) demonstrated a sharp drop of males captured with a very low density of dispensers, and then an approximately linear relationship between 90 and approaching 100% suppression. This near-linear portion of the profile includes both dispenser densities in which crop protection has been demonstrated, and densities in which it is unlikely. Suppression of males in pheromone traps was lost the next night after dispensers were removed, suggesting that the active ingredient was not persistent in the orchard environment. During most of the summer preharvest period, turning the dispensers off 1 or 2 h before the end of the predawn period of sexual activity provides the same amount of suppression of sexual communication as emission throughout the period of sexual activity. This suggests that encountering the pheromone from the mating disruption dispensers had a persistent effect on males. During the autumn postharvest period, only emission prior to midnight suppressed communication on nights on which the temperature fell below 19°C by midnight. These findings and the analysis will help manufacturers refine their offerings for mating disruption for this important California pest, and buyers of mating disruption to assess cost-effectiveness of competing offerings.


Assuntos
Mariposas , Atrativos Sexuais , Aerossóis , Animais , Controle de Insetos , Masculino , Feromônios/farmacologia , Reprodução , Comportamento Sexual Animal
13.
J Chem Ecol ; 46(3): 288-298, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31953705

RESUMO

Cowpea, Vigna unguiculata L. Walp. (Fabaceae), is one of the most important food legumes grown on the African continent, as it provides an affordable source of dietary protein. Yields of cowpea are significantly reduced through damage by legume pod-borer, Maruca vitrata (Lepidoptera: Crambidae), caterpillars to flowers, tender leaves and pods. Semiochemical-based strategies are considered as environmentally benign and affordable for pest management, particularly on smallholder farms. In this study, we investigated the importance of cowpea flower volatiles as host location cues for egg-laying M. vitrata, and herbivore-induced plant volatiles (HIPVs) as M. vitrata repellents and natural enemy (Apanteles taragamae and Phanerotoma syleptae parasitoid) attractants. In oviposition choice assays, M. vitrata laid more eggs on flowering cowpea plants than non-flowering plants. Coupled gas chromatography-electrophysiology (GC-EAG) analysis using the antennae of female M. vitrata and an extract of flower volatiles collected by dynamic headspace collection revealed the presence of five EAG-active components that were identified by coupled GC-mass spectrometry (GC-MS) analysis as benzaldehyde, benzyl alcohol, acetophenone, a vinylbenzaldehyde isomer and (E)-cinnamaldehyde. A synthetic blend of the identified compounds, prepared using 3-vinylbenzaldehyde, induced M. vitrata to lay as many eggs on non-flowering cowpea as on flowering plants. The moths also preferred laying eggs on intact plants compared to M. vitrata-infested plants. As the emission of EAG-active floral compounds was determined to be lower in the headspace of infested cowpea flowers, the role of HIPVs emitted by M. vitrata-damaged leaves was also investigated. Of the compounds induced by larval damage, (E)-DMNT, indole, n-hexyl acetate, 1-octen-3-ol and linalool were shown by GC-EAG to possess electrophysiological activity. A synthetic blend of the EAG-active compounds, using racemic 1-octen-3-ol and linalool, significantly reduced egg numbers on flowering cowpea. Larval and egg parasitoids, i.e. A. taragamae and Ph. syleptae, respectively, of M. vitrata both preferred the Y-tube olfactometer arm treated with synthetic (E)-DMNT, whereas preference for racemic linalool and (E)-nerolidol was dose-dependent in A. taragamae. Our results provide the platform for the development of future semiochemical-based pest management strategies against M. vitrata on smallholder farms in West Africa.


Assuntos
Controle de Insetos , Mariposas , Controle Biológico de Vetores , Feromônios/farmacologia , Vigna/química , Compostos Orgânicos Voláteis/farmacologia , Animais , Flores/química , Oviposição
14.
J Chem Ecol ; 46(3): 233-249, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31970605

RESUMO

Use of the first fish pheromone biopesticide, 3-keto petromyzonol sulfate (3kPZS) in sea lamprey (Petromyzon marinus) control requires an understanding of both how the amount 3kPZS applied to a trap relates to catch, and how that relationship varies among stream types. By conducting 3kPZS dose-response experiments over two years and across six varied trapping contexts, we conclude (1) that 3kPZS application is best standardized by how much is emitted from the trap instead of the fully mixed concentration achieved downstream, and (2) that 3kPZS is more effective in wide streams (>30 m). In wide streams, emission of 3kPZS at 50 mg hr.-1 from the trap increased capture rate by 10-15% as sea lamprey were 25-50% more likely to enter the trap after encounter. However, in narrow streams (< 15 m), 50 mg hr.-1 3kPZS generally reduced probabilities of upstream movement, trap encounter, and entrance. While 3kPZS significantly influenced upstream movement, encounter, and capture probabilities, these behaviors were also highly influenced by water temperature, stream width, sea lamprey length, and sex. This study highlights that a pheromone component in a stream environment does not ubiquitously increase trap catch in all contexts, but that where, how, and when the pheromone is applied has major impacts on whether it benefits or hinders trapping efforts.


Assuntos
Agentes de Controle Biológico/farmacologia , Ácidos Cólicos/farmacologia , Controle Biológico de Vetores/métodos , Petromyzon/fisiologia , Feromônios/farmacologia , Animais , Relação Dose-Resposta a Droga , Feminino , Masculino
15.
Int J Mol Sci ; 21(2)2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31963543

RESUMO

Sexually deceptive orchids typically depend on specific insect species for pollination, which are lured by sex pheromone mimicry. European Ophrys orchids often exploit specific species of wasps or bees with carboxylic acid derivatives. Here, we identify the specific semiochemicals present in O. insectifera, and in females of one of its pollinator species, Argogorytes fargeii. Headspace volatile samples and solvent extracts were analysed by GC-MS and semiochemicals were structurally elucidated by microderivatisation experiments and synthesis. (Z)-8-Heptadecene and n-pentadecane were confirmed as present in both O. insectifera and A. fargeii female extracts, with both compounds being found to be electrophysiologically active to pollinators. The identified semiochemicals were compared with previously identified Ophrys pollinator attractants, such as (Z)-9 and (Z)-12-C27-C29 alkenes in O. sphegodes and (Z)-9-octadecenal, octadecanal, ethyl linoleate and ethyl oleate in O. speculum, to provide further insights into the biosynthesis of semiochemicals in this genus. We propose that all these currently identified Ophrys semiochemicals can be formed biosynthetically from the same activated carboxylic acid precursors, after a sequence of elongation and decarbonylation reactions in O. sphegodes and O. speculum, while in O. insectifera, possibly by decarbonylation without preceding elongation.


Assuntos
Alcanos/farmacologia , Alcenos/farmacologia , Flores/fisiologia , Orchidaceae/fisiologia , Feromônios/farmacologia , Atrativos Sexuais/farmacologia , Alcanos/análise , Alcanos/química , Alcenos/análise , Alcenos/química , Animais , Abelhas , Flores/efeitos dos fármacos , Orchidaceae/efeitos dos fármacos , Feromônios/análise , Feromônios/química , Polinização , Atrativos Sexuais/análise , Atrativos Sexuais/química , Especificidade da Espécie , Vespas
16.
Ecotoxicol Environ Saf ; 190: 110180, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31927195

RESUMO

This paper studied the allelopathic effect of Cylindrotheca closterium on the growth of Prorocentrum donghaiense, the model of harmful algal blooms in aquatic environment, by the co-culture tests and bioassay-guided fraction methods. The growth of P. donghaiense in co-cultures was observably suppressed by C. closterium, and P. donghaiense biomass in C/P = 3: 1 group increased slowly with a low growth rate of 0.18 d-1 after 4 days. Petroleum ether (PE) extract derived from C. closterium filtrates was isolated by C18 column and the allelopathy of all isolated fractions for P. donghaiense was investigated. After 96 h cultivation, the inhibition ratio of PE-Ⅲ and PE-Ⅷ fractions on P. donghaiense could reach up to 70.2% and 64.3% at the concentration of 10-fold when compared to control, while the other fractions displayed relatively low inhibitory effects on P. donghaiense. PE-Ⅲ and PE-Ⅷ fractions also decreased the chlorophyll content and maximum quantum yield of photosystem II (Fv/Fm) of P. donghaiense cells. The activities of superoxide dismutase (SOD), one of antioxidant enzymes, reduced around 8.3% and 13.7% following exposure to 2-fold PE-Ⅲ and PE-Ⅷ, and was significantly decreased following higher exposure concentrations. After 96 h of 10-fold PE-Ⅲ and PE-Ⅷ treatments, Catalase (CAT) activity reduced to 44.86% and 46.42% of that observed in the control group. At the same time, a significant increase in malondialdehyde (MDA) contents was observed. These findings suggested that PE-Ⅲ and PE-Ⅷ fractions contained main allelochemicals and possibly acted as promising algistatic agents for emergency handling of P. donghaiense blooms.


Assuntos
Diatomáceas/química , Dinoflagelados/efeitos dos fármacos , Proliferação Nociva de Algas/efeitos dos fármacos , Herbicidas/farmacologia , Feromônios/farmacologia , Alelopatia , Biomassa , Clorofila/metabolismo , Dinoflagelados/crescimento & desenvolvimento , Herbicidas/isolamento & purificação , Feromônios/isolamento & purificação , Complexo de Proteína do Fotossistema II/metabolismo
17.
J Chem Ecol ; 46(1): 30-39, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31808075

RESUMO

Cerambycid beetles of the subfamily Lamiinae use male-produced aggregation-sex pheromones that are attractive to both sexes. Terpenoid pheromones have been identified from species in the tribes Acanthoderini and Acanthocinini native to North and South America, comprised of (E)-6,10-dimethyl-5,9-undecadien-2-one (geranylacetone), the structurally related 6-methylhept-5-en-2-one (sulcatone), and/or specific enantiomers or nonracemic ratios of enantiomers of the related compounds (E)-6,10-dimethyl-5,9-undecadien-2-ol (fuscumol), its acetate ester, (E)-6,10-dimethyl-5,9-undecadien-2-yl acetate (fuscumol acetate), and 6-methylhept-5-en-2-ol (sulcatol). Here, we present new information about the chemical ecology of six acanthoderine and acanthocinine species native to the eastern USA. The pheromone of Astyleiopus variegatus (Haldeman) previously was identified as a blend of (S)-fuscumol and (S)-fuscumol acetate, and we report here that geranylacetone is a synergistic component. Males of Aegomorphus modestus (Gyllenhal), Lepturges angulatus (LeConte), and Lepturges confluens (Haldeman) were found to produce similar blends composed of the enantiomers of fuscumol acetate and geranylacetone, whereas males of Astylidius parvus (LeConte) and Sternidius alpha (Say) produced both enantiomers of fuscumol together with (R)-fuscumol acetate and geranylacetone. Field experiments with synthesized chemicals revealed that species with similar pheromone composition nevertheless differed in their responses to individual components, and to various blends of components, and in how attraction was influenced by chemicals that were pheromone components of other species. Sulcatone and/or sulcatol antagonized attraction of some species to pheromones of the geranylacetone class, suggesting that there is an adaptive advantage in an ability to detect these heterospecific compounds, such as in avoiding cross attraction to other cerambycid species, as yet unknown, that use pheromones composed of both chemical classes.


Assuntos
Besouros/química , Feromônios/química , Animais , Besouros/metabolismo , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Feromônios/isolamento & purificação , Feromônios/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Especificidade da Espécie , Estereoisomerismo , Terpenos/química , Terpenos/isolamento & purificação , Terpenos/farmacologia , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação , Compostos Orgânicos Voláteis/farmacologia
18.
Nat Prod Res ; 34(6): 773-781, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30445848

RESUMO

New allelochemicals were identified through bio-guided fractionation from the ethyl acetate of seeds extracts, which was the most autotoxic compared to the other plant parts. Phytochemical investigation of the seeds extracts of C. arabica by spectroscopy analyses has led to identify two new dammarane type triterpenes (4 and 9), with nine known analogues (1 - 3, 5 - 8, 10 and 11), a new cucurbitane triterpene (12), acylated dehydrodiconiferyl alcohol (13), and three highly oxygenated flavonols (14-16). The most autotoxic compounds on germination and seedling growth were elucidated as dammarane type triterpenes. However, less autotoxic effect was recorded by an inhibition under 50% for most of the identified flavonoids. These results suggest that those autotoxic substances may be used as a new bio-herbicide that may contribute to manage the distribution of C. arabica in agronomic field.[Formula: see text].


Assuntos
Cleome/efeitos dos fármacos , Herbicidas/isolamento & purificação , Feromônios/farmacologia , Triterpenos/isolamento & purificação , Flavonóis/isolamento & purificação , Germinação/efeitos dos fármacos , Glicosídeos/isolamento & purificação , Herbicidas/química , Extratos Vegetais/química , Plântula/efeitos dos fármacos , Sementes/química , Triterpenos/química , Triterpenos/farmacologia
19.
Vet Rec ; 186(14): 449, 2020 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-31879321

RESUMO

BACKGROUND: Parturition and the initial postpartum period are important moments in the reproductive cycle of dogs. METHODS: A study assessed the effect of ADAPTIL, a dog-appeasing pheromone, on maternal behaviour during peripartum. Bitches were continuously exposed to ADAPTIL (n=20) or placebo (n=21) in double-blinded conditions from an average of about seven days before parturition up to 21 days postpartum. Differences in maternal behaviour in relation to the treatment were evaluated by the observation of specific activities through video recordings, such as the time spent by the bitch in close contact with the puppies, oronasal interaction and nursing duration and position. Videos were recorded at four time points (W0: within the first 48 hours of whelping; W1: one week after parturition; W2: two weeks after parturition; and W3: three weeks after parturition). In addition, the perception of breeders in relation to the quality of maternal care, puppies' wellbeing and overall relationship between the bitches and the puppies was evaluated using Visual Analogue Scale at the same time points. Moreover, the daily activity of the bitches was measured by using an electronic device (FitBark dog activity trackers, Kansas City, Missouri). RESULTS: For all observed maternal behaviours, there was a steady decrease in levels as the puppies developed, independently of treatment. However, bitches exposed to ADAPTIL tended to nurse significantly more in lying position, while those exposed to the placebo nursed more in a seated position, especially at W1 (P=0.06) and W3 (P=0.005). According to the breeders, the attention scores of bitches towards puppies were significantly higher in ADAPTIL than in the placebo group at each time point (P=0.01). Moreover, a difference according to parity was observed (P=0.004), with greater attention score displayed by primiparous bitches exposed to ADAPTIL compared with placebo on W0 (P=0.02), W1 and W3 (P<0.001). The global mother-puppies relationship was also perceived as significantly better (P=0.0002) by breeders of bitches exposed to ADAPTIL, with significant differences at W2 (P=0.01) and W3 (P=0.001). The bitches' daily activity increased starting two days before the whelp, peaked during parturition and then gradually declined up until four days postpartum. There was a trend towards a difference in the activity level according to the treatment during the full study period (P=0.09) and at two days before parturition (P=0.07). Bitches exposed to ADAPTIL were more active compared with placebo in relation to the FitBark data. CONCLUSION: The use of ADAPTIL in maternity modulated maternal behaviours. Concerning the caregiver's view, bitches under the influence of ADAPTIL had greater and extended attention towards the puppies and they were eager to stay with the puppies for a longer time.


Assuntos
Comportamento Animal/efeitos dos fármacos , Comportamento Materno/efeitos dos fármacos , Período Periparto , Feromônios/farmacologia , Animais , Animais Recém-Nascidos , Cães , Feminino , Gravidez
20.
J Chem Ecol ; 45(10): 823-837, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31701385

RESUMO

European badgers, Meles meles, are group-living in the UK, and demarcate their ranges with shared latrines. As carnivores, badgers possess paired anal glands, but olfactory information on the content of badger anal gland secretion (AGS) is largely uninvestigated. Here, we examined the volatile organic compounds (VOCs) of AGS samples from 57 free-living badgers using solid-phase microextraction (SPME) and gas chromatography-mass spectrometry. AGS was rich in alkanes (C7-C15, 14.3% of identified compounds), aldehydes (C5-C14, 9.7%), phenols (C6-C15, 9.5%), alcohols (C5-C10, 7.3%), aromatic hydrocarbons (C6-C13, 6.8%), ketones (C6-C13, 6.3%) and carboxylic acids (C3-C12, 5.6%) and contained a variety of esters, sulfurous and nitrogenous compounds, and ethers. The number of VOCs per profile ranged from 20 to 111 (mean = 65.4; ± 22.7 SD), but no compound was unique for any of the biological categories. After normalization of the raw data using Probabilistic Quotient Normalization, we produced a resemblance matrix by calculating the Euclidian distances between all sample pairs. PERMANOVA revealed that AGS composition differs between social groups, and concentration and complexity in terms of number of measurable VOCs varies between seasons and years. AGS VOC profiles encode individual identity, sex and vary with female reproductive state, indicating an important function in intraspecific communication. Because AGS is excreted together with fecal deposits, we conclude that chemical complexity of AGS enables particularly latrine-using species, such as badgers, to advertise more complex individual-specific information than in feces alone.


Assuntos
Canal Anal/química , Mustelidae/fisiologia , Feromônios/química , Alcanos/química , Alcanos/isolamento & purificação , Alcanos/farmacologia , Canal Anal/metabolismo , Comunicação Animal , Animais , Comportamento Animal/efeitos dos fármacos , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Feromônios/isolamento & purificação , Feromônios/farmacologia , Estações do Ano , Microextração em Fase Sólida , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação , Compostos Orgânicos Voláteis/farmacologia
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