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Yan R, Chen P, Xu Z, Qian J, Zhu G, Jin Y, Chen B, Chen M. A potential link between aromatics-induced oviposition repellency behaviors and specific odorant receptor of Aedes albopictus. PEST MANAGEMENT SCIENCE 2024; 80:3603-3611. [PMID: 38458148 DOI: 10.1002/ps.8064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 02/21/2024] [Accepted: 03/07/2024] [Indexed: 03/10/2024]
Abstract
BACKGROUND The Asian tiger mosquito, Aedes albopictus, is a competent vector for the spread of several viral arboviruses including dengue, chikungunya, and Zika. Several vital mosquito behaviors linked to survival and reproduction are primarily dependent on a sophisticated olfactory system for semiochemical perception. However, a limited number of studies has hampered our understanding of the relationship between the A. albopictus acute olfactory system and the complex chemical world. RESULTS Here, we performed a qRT-PCR assay on antennae from A. albopictus of differing sex, age and physiological states, and found that AalbOr10 was enriched in blood-fed female mosquitoes. We then undertook single sensillum recording to de-orphan AalbOr10 using a panel of physiologically and behaviorally relevant odorants in a Drosophila 'empty neuron' system. The results indicated that AalbOr10 was activated by seven aromatic compounds, all of which hampered egg-laying in blood-fed mosquitoes. Furthermore, using a post-RNA interference oviposition assay, we found that reducing the transcript level of AalbOr10 affected repellent activity mediated by 2-ethylphenol at low concentrations (10-4 vol/vol). Computational modeling and molecular docking studies suggested that hydrogen bonds to Y68 and Y150 mediated the interaction of 2-ethylphenol with AalbOr10. CONCLUSION We reveal a potential link between aromatics-induced oviposition repellency behaviors and a specific odorant receptor in A. albopictus. Our findings provide a foundation for identifying active semiochemicals for the monitoring or controlling of mosquito populations. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Ru Yan
- College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Peitong Chen
- Institute of Pesticide and Environmental Toxicology, Zhejiang University, Hangzhou, China
| | - Zhanyi Xu
- Institute of Pesticide and Environmental Toxicology, Zhejiang University, Hangzhou, China
| | - Jiali Qian
- Institute of Pesticide and Environmental Toxicology, Zhejiang University, Hangzhou, China
| | - Guonian Zhu
- Institute of Pesticide and Environmental Toxicology, Zhejiang University, Hangzhou, China
| | - Yongfeng Jin
- College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Bosheng Chen
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
| | - Mengli Chen
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
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Vainer Y, Wang Y, Huff RM, Perets D, Sar-Shalom E, Yakir E, Ghaninia M, Coutinho-Abreu Gomes IV, Ruiz C, Rajamanickam D, Warburg A, Akbari OS, Papathanos PA, Ignell R, Riffell JA, Pitts RJ, Bohbot JD. A conserved odorant receptor underpins borneol-mediated repellency in culicine mosquitoes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.08.01.548337. [PMID: 37577635 PMCID: PMC10418152 DOI: 10.1101/2023.08.01.548337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
The use of essential oils derived from the camphor tree to repel mosquitoes is an ancient practice that originated in Southeast Asia and gradually spread to China and across Europe via the Maritime Silk Road. The olfactory mechanisms by which these oils elicit avoidance behavior are unclear. Here we show that plant bicyclic monoterpenoids and borneol specifically activate a neural pathway that originates in the orphan olfactory receptor neuron of the capitate peg sensillum in the maxillary palp, and projects to the mediodorsal glomerulus 3 in the antennal lobe. This neuron co-locates with two olfactory receptor neurons tuned to carbon dioxide and octenol that mediate human-host detection. We also confirm that borneol elicits repellency against human-seeking female mosquitoes. Understanding the functional role of the mosquito maxillary palp is essential to investigating olfactory signal integration and host-selection behavior.
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Affiliation(s)
- Yuri Vainer
- Department of Entomology, The Hebrew University of Jerusalem, Israel
| | - Yinliang Wang
- Department of Entomology, The Hebrew University of Jerusalem, Israel
- Northeast Normal University, China
| | | | - Dor Perets
- Department of Entomology, The Hebrew University of Jerusalem, Israel
| | | | - Esther Yakir
- Department of Entomology, The Hebrew University of Jerusalem, Israel
| | - Majid Ghaninia
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Sweden
| | | | - Carlos Ruiz
- Department of Biology, University of Washington, USA
| | | | - A. Warburg
- Department of Microbiology and Molecular Genetics, The Hebrew University of Jerusalem, Israel
| | - Omar S. Akbari
- Division of Biological Sciences, University of California, USA
| | | | - R. Ignell
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Sweden
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3
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Ai S, Zhang Y, Chen Y, Zhang T, Zhong G, Yi X. Insect-Microorganism Interaction Has Implicates on Insect Olfactory Systems. INSECTS 2022; 13:1094. [PMID: 36555004 PMCID: PMC9787996 DOI: 10.3390/insects13121094] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/23/2022] [Accepted: 11/25/2022] [Indexed: 06/17/2023]
Abstract
Olfaction plays an essential role in various insect behaviors, including habitat selection, access to food, avoidance of predators, inter-species communication, aggregation, and reproduction. The olfactory process involves integrating multiple signals from external conditions and internal physiological states, including living environments, age, physiological conditions, and circadian rhythms. As microorganisms and insects form tight interactions, the behaviors of insects are constantly challenged by versatile microorganisms via olfactory cues. To better understand the microbial influences on insect behaviors via olfactory cues, this paper summarizes three different ways in which microorganisms modulate insect behaviors. Here, we deciphered three interesting aspects of microorganisms-contributed olfaction: (1) How do volatiles emitted by microorganisms affect the behaviors of insects? (2) How do microorganisms reshape the behaviors of insects by inducing changes in the synthesis of host volatiles? (3) How do symbiotic microorganisms act on insects by modulating behaviors?
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Affiliation(s)
- Shupei Ai
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
| | - Yuhua Zhang
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
| | - Yaoyao Chen
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
| | - Tong Zhang
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
| | - Guohua Zhong
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
| | - Xin Yi
- Key Laboratory of Crop Integrated Pest Management in South China, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
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Mulatier M, Boullis A, Vega-Rúa A. Semiochemical oviposition cues to control Aedes aegypti gravid females: state of the art and proposed framework for their validation. Parasit Vectors 2022; 15:228. [PMID: 35752845 PMCID: PMC9233825 DOI: 10.1186/s13071-022-05337-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 05/24/2022] [Indexed: 11/28/2022] Open
Abstract
In the fight against mosquito-borne diseases, odour-based lures targeting gravid females represent a promising alternative to conventional tools for both reducing mosquito populations and monitoring pathogen transmission. To be sustainable and effective, they are expected to use semiochemicals that act specifically against the targeted vector species. In control programmes directed against Aedes aegypti, several candidates of different origins (conspecifics, plants) have already been identified as potential oviposition attractants or repellents in laboratory experiments. However, few of these candidates have received validation in field experiments, studies depicting the active molecules and their mode of perception are still scarce, and there are several methodological challenges (i.e. lack of standardization, differences in oviposition index interpretation and use) that should be addressed to ensure a better reproducibility and accelerate the validation of candidates. In this review, we address the state of the art of the compounds identified as potential candidates for trap development against Ae. aegypti and their level of validation. We also offer a critical methodological analysis, highlight remaining gaps and research priorities, and propose a workflow to validate these candidates and to increase the panel of odours available to specifically trap Ae. aegypti.
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Affiliation(s)
- Margaux Mulatier
- Laboratory of Vector Control Research, Institute Pasteur of Guadeloupe, Lieu-dit Morne Jolivière, 97139, Les Abymes, Guadeloupe, France.
| | - Antoine Boullis
- TERRA, Gembloux Agro-Bio Tech, University of Liège, Avenue de la Faculté 2B, 5030, Gembloux, Belgium
| | - Anubis Vega-Rúa
- Laboratory of Vector Control Research, Institute Pasteur of Guadeloupe, Lieu-dit Morne Jolivière, 97139, Les Abymes, Guadeloupe, France
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5
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Neuronal odor coding in the larval sensory cone of Anopheles coluzzii: Complex responses from a simple system. Cell Rep 2021; 36:109555. [PMID: 34407405 PMCID: PMC8420959 DOI: 10.1016/j.celrep.2021.109555] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 05/18/2021] [Accepted: 07/28/2021] [Indexed: 11/20/2022] Open
Abstract
Anopheles mosquitoes are the sole vectors of malaria. Although adult females are directly responsible for disease transmission and accordingly have been extensively studied, the survival of pre-adult larval stages is vital. Mosquito larvae utilize a spectrum of chemosensory and other cues to navigate their aquatic habitats to avoid predators and search for food. Here we examine larval olfactory responses, in which the peripheral components are associated with the antennal sensory cone. Larval behavior and sensory cone responses to volatile stimuli in Anopheles coluzzii demonstrate the sensory cone is particularly tuned to alcohols, thiazoles, and heterocyclics, and these responses can be assigned to discrete groups of sensory cone neurons with distinctive profiles. These studies reveal that the anopheline larvae actively sample volatile odors above their aquatic habitats via a highly sophisticated olfactory system that is sensitive to a broad range of compounds with significant behavioral relevance. Sun et al. investigate larval sensory cone and behavioral responses to volatile stimuli in Anopheles coluzzii. They find that malaria mosquito larvae actively sample volatile odors above their aquatic habitats via a highly sophisticated olfactory system that is sensitive to a broad range of compounds with significant behavioral relevance.
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Crowley-Gall A, Shaw M, Rollmann SM. Host Preference and Olfaction in Drosophila mojavensis. J Hered 2020; 110:68-79. [PMID: 30299456 DOI: 10.1093/jhered/esy052] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 09/24/2018] [Indexed: 11/12/2022] Open
Abstract
Many organisms live in complex environments that vary geographically in resource availability. This environmental heterogeneity can lead to changes within species in their phenotypic traits. For example, in many herbivorous insects, variation in host plant availability has been shown to influence insect host preference behavior. This behavior can be mediated in part through the insect olfactory system and the odor-evoked responses of olfactory sensory neurons (OSNs), which are in turn mediated by their corresponding odorant receptor genes. The desert dwelling fly Drosophila mojavensis is a model species for understanding the mechanisms underlying host preference in a heterogeneous environment. Depending on geographic region, one to multiple host plant species are available. Here, we conducted electrophysiological studies and found variation in responses of ORNs to host plant volatiles both within and between 2 populations-particularly to the odorant 4-methylphenol. Flies from select localities within each population were found to lack a response to 4-methylphenol. Experiments then assessed the extent to which these electrophysiological differences were associated with differences in several odor-mediated behavioral responses. No association between the presence/absence of these odor-evoked responses and short range olfactory behavior or oviposition behavior was observed. However, differences in odor-induced feeding behavior in response to 4-methylphenol were found. Localities that exhibit an odor-evoked response to the odorant had increased feeding behavior in the presence of the odorant. This study sets the stage for future work examining the functional genetics underlying variation in odor perception.
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Affiliation(s)
- Amber Crowley-Gall
- Department of Biological Sciences, University of Cincinnati, Clifton Court, Cincinnati, OH
| | - Mary Shaw
- Department of Biological Sciences, University of Cincinnati, Clifton Court, Cincinnati, OH
| | - Stephanie M Rollmann
- Department of Biological Sciences, University of Cincinnati, Clifton Court, Cincinnati, OH
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Melo N, Wolff GH, Costa-da-Silva AL, Arribas R, Triana MF, Gugger M, Riffell JA, DeGennaro M, Stensmyr MC. Geosmin Attracts Aedes aegypti Mosquitoes to Oviposition Sites. Curr Biol 2019; 30:127-134.e5. [PMID: 31839454 PMCID: PMC7144812 DOI: 10.1016/j.cub.2019.11.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 09/29/2019] [Accepted: 11/01/2019] [Indexed: 12/18/2022]
Abstract
Melo et al. show that geosmin mediates egg laying in the yellow fever mosquito Aedes aegypti, which associates geosmin with microbes present in the larval aquatic habitat. The authors further show that geosmin can be used as bait in oviposition traps and that geosmin can be substituted by beetroot peel for mosquito trapping in developing countries.
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Affiliation(s)
- Nadia Melo
- Department of Biology, Lund University, 22362 Lund, Sweden
| | - Gabriella H Wolff
- Department of Biology, University of Washington, Seattle, WA 98195-1800, USA
| | - Andre Luis Costa-da-Silva
- Department of Biological Sciences & Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
| | - Robert Arribas
- Department of Biological Sciences & Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
| | - Merybeth Fernandez Triana
- Department of Biology, Lund University, 22362 Lund, Sweden; Instituto de Quimica e Biotecnologia, Universidade Federal de Alagoas, Maceio 5702-970, Brazil
| | - Muriel Gugger
- Collection of Cyanobacteria, Institut Pasteur, 75015 Paris, France
| | - Jeffrey A Riffell
- Department of Biology, University of Washington, Seattle, WA 98195-1800, USA
| | - Matthew DeGennaro
- Department of Biological Sciences & Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
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Cartography of odor chemicals in the dengue vector mosquito (Aedes aegypti L., Diptera/Culicidae). Sci Rep 2019; 9:8510. [PMID: 31186462 PMCID: PMC6559988 DOI: 10.1038/s41598-019-44851-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 05/23/2019] [Indexed: 11/29/2022] Open
Abstract
This study was aimed to identify the chemical compounds of Aedes aegypti that can be potentially used to develop pheromone-based vector control methods. In this study, we compared the chemical compounds collected from the organs of mosquitoes at different developmental stages in the life cycle. We also compared the composition and amount of extracts from the different tissues of male and female adult mosquito. Interestingly, we found large amount of C17-C20 ethyl and methyl esters in the wings of female and antennae of male mosquito. We also found that isopropyl esters, dodelactone, octadecenoic acid and medium-chain fatty acid increase drastically during the late larval stage (L4). Old adult mosquitoes showed remarkable increase in production of C16:1 and C18:1 methyl esters, as a first example of chemical signatures specifically associated with aging in the animals. This knowledge may open the ground to find new behaviorally-important molecules with the ability to control Aedes specifically.
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Gaburro J, Paradkar PN, Klein M, Bhatti A, Nahavandi S, Duchemin JB. Dengue virus infection changes Aedes aegypti oviposition olfactory preferences. Sci Rep 2018; 8:13179. [PMID: 30181545 PMCID: PMC6123472 DOI: 10.1038/s41598-018-31608-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 08/08/2018] [Indexed: 12/27/2022] Open
Abstract
Aedes aegypti mosquitoes, main vectors for numerous flaviviruses, have olfactory preferences and are capable of olfactory learning especially when seeking their required environmental conditions to lay their eggs. In this study, we showed that semiochemical conditions during Aedes aegypti larval rearing affected future female choice for oviposition: water-reared mosquitoes preferred to lay eggs in water or p-cresol containers, while skatole reared mosquitoes preferred skatole sites. Using two independent behavioural assays, we showed that this skatole preference was lost in mosquitoes infected with dengue virus. Viral RNA was extracted from infected female mosquito heads, and an increase of virus load was detected from 3 to 10 days post infection, indicating replication in the insect head and possibly in the central nervous system. Expression of selected genes, potentially implied in olfactory learning processes, were also altered during dengue infection. Based on these results, we hypothesise that dengue virus infection alters gene expression in the mosquito’s head and is associated with a loss of olfactory preferences, possibly modifying oviposition site choice of female mosquitoes.
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Affiliation(s)
- Julie Gaburro
- CSIRO Health and Biosecurity, Australian Animal Health Laboratory, Geelong, Australia.,Institute for Intelligent Systems Research and Innovation (IISRI), Deakin University, Waurn Ponds, Australia
| | - Prasad N Paradkar
- CSIRO Health and Biosecurity, Australian Animal Health Laboratory, Geelong, Australia
| | - Melissa Klein
- CSIRO Health and Biosecurity, Australian Animal Health Laboratory, Geelong, Australia
| | - Asim Bhatti
- Institute for Intelligent Systems Research and Innovation (IISRI), Deakin University, Waurn Ponds, Australia
| | - Saeid Nahavandi
- Institute for Intelligent Systems Research and Innovation (IISRI), Deakin University, Waurn Ponds, Australia
| | - Jean-Bernard Duchemin
- CSIRO Health and Biosecurity, Australian Animal Health Laboratory, Geelong, Australia.
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Gaburro J, Duchemin JB, Paradkar PN, Nahavandi S, Bhatti A. Assessment of ICount software, a precise and fast egg counting tool for the mosquito vector Aedes aegypti. Parasit Vectors 2016; 9:590. [PMID: 27863526 PMCID: PMC5116143 DOI: 10.1186/s13071-016-1870-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 11/02/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Widespread in the tropics, the mosquito Aedes aegypti is an important vector of many viruses, posing a significant threat to human health. Vector monitoring often requires fecundity estimation by counting eggs laid by female mosquitoes. Traditionally, manual data analyses have been used but this requires a lot of effort and is the methods are prone to errors. An easy tool to assess the number of eggs laid would facilitate experimentation and vector control operations. RESULTS This study introduces a built-in software called ICount allowing automatic egg counting of the mosquito vector, Aedes aegypti. ICount egg estimation compared to manual counting is statistically equivalent, making the software effective for automatic and semi-automatic data analysis. This technique also allows rapid analysis compared to manual methods. Finally, the software has been used to assess p-cresol oviposition choices under laboratory conditions in order to test the system with different egg densities. CONCLUSIONS ICount is a powerful tool for fast and precise egg count analysis, freeing experimenters from manual data processing. Software access is free and its user-friendly interface allows easy use by non-experts. Its efficiency has been tested in our laboratory with oviposition dual choices of Aedes aegypti females. The next step will be the development of a mobile application, based on the ICount platform, for vector monitoring surveys in the field.
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Affiliation(s)
- Julie Gaburro
- Institute for Intelligent Systems Research and Innovation (IISRI), Deakin University, 75 Pigdons Road, Waurn Ponds, VIC 3216 Australia
- CSIRO Health & Biosecurity, Australian Animal Health Laboratory, 5 Portarlington Rd, East Geelong, VIC 3220 Australia
| | - Jean-Bernard Duchemin
- CSIRO Health & Biosecurity, Australian Animal Health Laboratory, 5 Portarlington Rd, East Geelong, VIC 3220 Australia
| | - Prasad N. Paradkar
- CSIRO Health & Biosecurity, Australian Animal Health Laboratory, 5 Portarlington Rd, East Geelong, VIC 3220 Australia
| | - Saeid Nahavandi
- Institute for Intelligent Systems Research and Innovation (IISRI), Deakin University, 75 Pigdons Road, Waurn Ponds, VIC 3216 Australia
| | - Asim Bhatti
- Institute for Intelligent Systems Research and Innovation (IISRI), Deakin University, 75 Pigdons Road, Waurn Ponds, VIC 3216 Australia
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Overhead tank is the potential breeding habitat of Anopheles stephensi in an urban transmission setting of Chennai, India. Malar J 2016; 15:274. [PMID: 27169513 PMCID: PMC4865005 DOI: 10.1186/s12936-016-1321-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 04/30/2016] [Indexed: 12/02/2022] Open
Abstract
Background Wells and overhead tanks (OHT) are the major breeding sources of the local malaria vector, Anopheles stephensi in the Indian city of Chennai; they play a significant role in vector breeding, and transmission of urban malaria. Many other man-made breeding habitats, such as cemented cisterns/containers, barrels or drums, sumps or underground tanks, and plastic pots/containers are maintained to supplement water needs, temporarily resulting in enhanced mosquito/vector breeding. Correlating breeding habitats with immature vector abundance is important in effective planning to strengthen operational execution of vector control measures. Methods A year-long, weekly study was conducted in Chennai to inspect available clear/clean water mosquito breeding habitats. Different breeding features, such as instar-wise, immature density and co-inhabitation with other mosquito species, were analysed. The characteristics of breeding habitats, i.e., type of habitat, water temperature and presence of aquatic organisms, organic matter and green algal remnants on the water surface at the time of inspection, were also studied. Immature density of vector was correlated with presence of other mosquito species, malaria prevalence, habitat characteristics and monthly/seasonal fluctuations. All the data collected from field observations were analysed using standard statistical tools. Results When the immature density of breeding habitats was analysed, using one-way ANOVA, it was observed that the density did not change in a significant way either across seasons or months. OHTs contributed significantly to the immature population when compared to wells and other breeding habitats of the study site. The habitat positivity of wells and OHTs was significantly associated with the presence of aquatic organisms, organic matter and algal remnants. Significant correlations of malaria prevalence with monthly immature density, as well as number of breeding habitats with immature vector mosquitoes, were also observed. Conclusions The findings that OHTs showed fairly high and consistent immature density of An. stephensi irrespective of seasons indicates the potentiality of the breeding habitat in contributing to vector density. The correlation between vector breeding habitats, immature density and malaria prevalence indicates the proximity of these habitats to malaria cases, proving its role in vector abundance and local malaria transmission. The preference of An. stephensi to breed in OHTs calls for intensified, appropriate and sustained intervention measures to curtail vector breeding and propagation to shrink malaria to pre-elimination level and beyond.
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12
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Suh E, Choe DH, Saveer AM, Zwiebel LJ. Suboptimal Larval Habitats Modulate Oviposition of the Malaria Vector Mosquito Anopheles coluzzii. PLoS One 2016; 11:e0149800. [PMID: 26900947 PMCID: PMC4768836 DOI: 10.1371/journal.pone.0149800] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 02/04/2016] [Indexed: 01/08/2023] Open
Abstract
Selection of oviposition sites by gravid females is a critical behavioral step in the reproductive cycle of Anopheles coluzzii, which is one of the principal Afrotropical malaria vector mosquitoes. Several studies suggest this decision is mediated by semiochemicals associated with potential oviposition sites. To better understand the chemosensory basis of this behavior and identify compounds that can modulate oviposition, we examined the generally held hypothesis that suboptimal larval habitats give rise to semiochemicals that negatively influence the oviposition preference of gravid females. Dual-choice bioassays indicated that oviposition sites conditioned in this manner do indeed foster significant and concentration dependent aversive effects on the oviposition site selection of gravid females. Headspace analyses derived from aversive habitats consistently noted the presence of dimethyl disulfide (DMDS), dimethyl trisulfide (DMTS) and 6-methyl-5-hepten-2-one (sulcatone) each of which unitarily affected An. coluzzii oviposition preference. Electrophysiological assays across the antennae, maxillary palp, and labellum of gravid An. coluzzii revealed differential responses to these semiochemicals. Taken together, these findings validate the hypothesis in question and suggest that suboptimal environments for An. coluzzii larval development results in the release of DMDS, DMTS and sulcatone that impact the response valence of gravid females.
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Affiliation(s)
- Eunho Suh
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Dong-Hwan Choe
- Department of Entomology, University of California, Riverside, California, United States of America
| | - Ahmed M. Saveer
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Laurence J. Zwiebel
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Pharmacology, Vanderbilt Brain Institute, Program in Developmental Biology, and Institutes of Chemical Biology and Global Health, Vanderbilt University Medical Center, Tennessee, United States of America
- * E-mail:
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Afify A, Galizia CG. Chemosensory Cues for Mosquito Oviposition Site Selection. JOURNAL OF MEDICAL ENTOMOLOGY 2015; 52:120-30. [PMID: 26336295 DOI: 10.1093/jme/tju024] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2014] [Accepted: 12/01/2014] [Indexed: 05/10/2023]
Abstract
Gravid mosquitoes use chemosensory (olfactory, gustatory, or both) cues to select oviposition sites suitable for their offspring. In nature, these cues originate from plant infusions, microbes, mosquito immature stages, and predators. While attractants and stimulants are cues that could show the availability of food (plant infusions and microbes) and suitable conditions (the presence of conspecifics), repellents and deterrents show the risk of predation, infection with pathogens, or strong competition. Many studies have addressed the question of which substances can act as positive or negative cues in different mosquito species, with sometimes apparently contradicting results. These studies often differ in species, substance concentration, and other experimental details, making it difficult to compare the results. In this review, we compiled the available information for a wide range of species and substances, with particular attention to cues originating from larval food, immature stages, predators, and to synthetic compounds. We note that the effect of many substances differs between species, and that many substances have been tested in few species only, revealing that the information is scattered across species, substances, and experimental conditions.
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Affiliation(s)
- Ali Afify
- Department of Neurobiology, University of Konstanz, Universitätsstraße 10, D-78457, Konstanz, Germany.Corresponding author, e-mail:
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