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Sample records for anopheles stephensi mosquitoes

  1. A Physical Map for an Asian Malaria Mosquito, Anopheles stephensi

    OpenAIRE

    Maria V Sharakhova; Xia, Ai; Tu, Zhijian; Shouche, Yogesh S.; Unger, Maria F; Sharakhov, Igor V

    2010-01-01

    Physical mapping is a useful approach for studying genome organization and evolution as well as for genome sequence assembly. The availability of polytene chromosomes in malaria mosquitoes provides a unique opportunity to develop high-resolution physical maps. We report a 0.6-Mb-resolution physical map consisting of 422 DNA markers hybridized to 379 chromosomal sites of the Anopheles stephensi polytene chromosomes. This makes An. stephensi second only to Anopheles gambiae in density of a phys...

  2. Laser induced mortality of Anopheles stephensi mosquitoes

    Science.gov (United States)

    Keller, Matthew D.; Leahy, David J.; Norton, Bryan J.; Johanson, Threeric; Mullen, Emma R.; Marvit, Maclen; Makagon, Arty

    2016-02-01

    Small, flying insects continue to pose great risks to both human health and agricultural production throughout the world, so there remains a compelling need to develop new vector and pest control approaches. Here, we examined the use of short (mosquitoes, which were chosen as a representative species. The mortality of mosquitoes exposed to laser pulses of various wavelength, power, pulse duration, and spot size combinations was assessed 24 hours after exposure. For otherwise comparable conditions, green and far-infrared wavelengths were found to be more effective than near- and mid-infrared wavelengths. Pulses with larger laser spot sizes required lower lethal energy densities, or fluence, but more pulse energy than for smaller spot sizes with greater fluence. Pulse duration had to be reduced by several orders of magnitude to significantly lower the lethal pulse energy or fluence required. These results identified the most promising candidates for the lethal laser component in a system being designed to identify, track, and shoot down flying insects in the wild.

  3. Mosquito repellent potential of Pithecellobium dulce leaf and seed against malaria vector Anopheles stephensi (Diptera: Culicidae)

    OpenAIRE

    Mohan Rajeswary; Marimuthu Govindarajan

    2016-01-01

    Objective: To determine the repellent properties of hexane, benzene, ethyl acetate, chloroform and methanol extract of Pithecellobium dulce (P. dulce) leaf and seed against Anopheles stephensi (An. stephensi). Methods: Repellent activity assay was carried out in a net cage (45 cm × 30 cm × 25 cm) containing 100 blood starved female mosquitoes of An. stephensi. This assay was carried out in the laboratory conditions according to the WHO 2009 protocol. Plant crude extracts of P. ...

  4. Mosquito repellent action of Blumea lacera (Asteraceae) against Anopheles stephensi and Culex quinquefasciatus.

    OpenAIRE

    Singh, S.P.; MITTAL, P.K.

    2014-01-01

    Petroleum ether extract of Blumea lacera was screened under laboratory conditions for repellent activity against mosquito vector Anopheles stephensi Liston and Culex quinquefasciatus Say (Diptera: Culicidae). The repellent activity of Blumea lacera extract was tested against mosquitoes in comparison with the DEET, which was used as a positive control. Results obtained from the laboratory experiment showed that the extract was effective against mosquito vectors even at a low dose. A direct rel...

  5. Mosquito repellent action of Blumea lacera (Asteraceae against Anopheles stephensi and Culex quinquefasciatus.

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    S.P. Singh

    2014-03-01

    Full Text Available Petroleum ether extract of Blumea lacera was screened under laboratory conditions for repellent activity against mosquito vector Anopheles stephensi Liston and Culex quinquefasciatus Say (Diptera: Culicidae. The repellent activity of Blumea lacera extract was tested against mosquitoes in comparison with the DEET, which was used as a positive control. Results obtained from the laboratory experiment showed that the extract was effective against mosquito vectors even at a low dose. A direct relationship was observed with concentrations of Blumea lacera extract and the repellent activity. Percent repellency obtained at 6% concentration of theextract against An. stephensi and Cx. quinquefasciatus were 97and 98% at 0 hour and 78.8 and 76.2% after 6 hrs. DEET-2% however showed 100% repellency against An. stephensi and against Cx. quinquefasciatus up to 4 hours and 1 hour, respectively. These results show that Blumea lacera extract has the potential as an effective mosquito repellent.

  6. Larvicidal and repellent properties of Adansonia digitata against medically important human malarial vector mosquito Anopheles stephensi (Diptera: Culicidae)

    OpenAIRE

    K. Krishnappa , K. Elumalai , S. Dhanasekaran & J. Gokulakrishnan

    2012-01-01

    Background & objectives: Development of plant-based alternative compounds for mosquito control has gainedimportance now-a-days, in view of increasing resistance in mosquito vectors to existing insecticides. The larvicidaland repellent activities of benzene, chloroform, hexane and methanol leaf extracts of Indian medicinal plant,Adansonia digitata were investigated against malarial vector, Anopheles stephensi.Methods: In all, 25 III instar larvae of An. stephensi were exposed to various concen...

  7. Mosquito repellent potential of Pithecellobium dulce leaf and seed against malaria vector Anopheles stephensi (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Mohan Rajeswary

    2016-03-01

    Full Text Available Objective: To determine the repellent properties of hexane, benzene, ethyl acetate, chloroform and methanol extract of Pithecellobium dulce (P. dulce leaf and seed against Anopheles stephensi (An. stephensi. Methods: Repellent activity assay was carried out in a net cage (45 cm × 30 cm × 25 cm containing 100 blood starved female mosquitoes of An. stephensi. This assay was carried out in the laboratory conditions according to the WHO 2009 protocol. Plant crude extracts of P. dulce were applied at 1.0, 2.5, and 5.0 mg/cm2 separately in the exposed fore arm of study subjects. Ethanol was used as the sole control. Results: In this study, the applied plant crude extracts were observed to protect against mosquito bites. There were no allergic reactions experienced by the study subjects. The repellent activity of the extract was dependent on the concentration of the extract. Among the tested solvents, the leaf and seed methanol extract showed the maximum efficacy. The highest concentration of 5.0 mg/cm2 leaf and seed methanol extract of P. dulce provided over 180 min and 150 min protection, respectively. Conclusions: Crude extracts of P. dulce exhibit the potential for controlling malaria vector mosquito An. stephensi.

  8. Mosquito Larvicidal Potential of Gossypium hirsutum (Bt cotton) Leaves Extracts against Aedes aegypti and Anopheles stephensi larvae.

    OpenAIRE

    Patil, Chandrashekhar D; Hemant P Borase; Salunkhe, Rahul B; Rahul K Suryawanshi; Narkhade, Chandrakant P; Salunke, Bipinchandra K.; Satish V Patil

    2014-01-01

    Background: We aimed to extract the ingredients from leaves of Gossypium hirsutum (Bt cotton) using different solvents and evaluate for potential use to control different larval stages of mosquito species, Aedes aegypti and Anopheles stephensi. Methods: Qualitative and quantitative estimation of ingredients from Go. hirsutum (Bt) plant extract was carried out and their inhibitory action against mosquito larvae was determined using mosquito larvicidal assay. Results: LC50 values of water, etha...

  9. Molecular interactions between Anopheles stephensi midgut cells and Plasmodium berghei: the time bomb theory of ookinete invasion of mosquitoes

    OpenAIRE

    Han, Yeon Soo; Thompson, Joanne; Kafatos, Fotis C.; Barillas-Mury, Carolina

    2000-01-01

    We present a detailed analysis of the interactions between Anopheles stephensi midgut epithelial cells and Plasmodium berghei ookinetes during invasion of the mosquito by the parasite. In this mosquito, P.berghei ookinetes invade polarized columnar epithelial cells with microvilli, which do not express high levels of vesicular ATPase. The invaded cells are damaged, protrude towards the midgut lumen and suffer other characteristic changes, including induction of nitric oxide synthase (NOS) exp...

  10. Analysis of two novel midgut-specific promoters driving transgene expression in Anopheles stephensi mosquitoes.

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    Tony Nolan

    Full Text Available BACKGROUND: Tissue-specific promoters controlling the expression of transgenes in Anopheles mosquitoes represent a valuable tool both for studying the interaction between these malaria vectors and the Plasmodium parasites they transmit and for novel malaria control strategies based on developing Plasmodium-refractory mosquitoes by expressing anti-parasitic genes. With this aim we have studied the promoter regions of two genes from the most important malaria vector, Anopheles gambiae, whose expression is strongly induced upon blood feeding. RESULTS: We analysed the A. gambiae Antryp1 and G12 genes, which we have shown to be midgut-specific and maximally expressed at 24 hours post-bloodmeal (PBM. Antryp1, required for bloodmeal digestion, encodes one member of a family of 7 trypsin genes. The G12 gene, of unknown function, was previously identified in our laboratory in a screen for genes induced in response to a bloodmeal. We fused 1.1 kb of the upstream regions containing the putative promoter of these genes to reporter genes and transformed these into the Indian malaria vector A. stephensi to see if we could recapitulate the expression pattern of the endogenous genes. Both the Antryp1 and G12 upstream regions were able to drive female-predominant, midgut-specific expression in transgenic mosquitoes. Expression of the Antryp1-driven reporter in transgenic A. stephensi lines was low, undetectable by northern blot analysis, and failed to fully match the induction kinetics of the endogenous Antryp1 gene in A. gambiae. This incomplete conservation of expression suggests either subtle differences in the transcriptional machinery between A. stephensi and A. gambiae or that the upstream region chosen lacked all the control elements. In contrast, the G12 upstream region was able to faithfully reproduce the expression profile of the endogenous A. gambiae gene, showing female midgut specificity in the adult mosquito and massive induction PBM, peaking at 24

  11. Taxonomy Icon Data: Anopheles stephensi [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available Anopheles stephensi Anopheles stephensi Arthropoda Anopheles_stephensi_L.png Anopheles_stephen...si_NL.png Anopheles_stephensi_S.png Anopheles_stephensi_NS.png http://biosciencedbc.jp/taxonomy_i...con/icon.cgi?i=Anopheles+stephensi&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Anopheles+stephensi&...t=NL http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Anopheles+stephensi&t=S htt...p://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Anopheles+stephensi&t=NS http://togodb.biosciencedbc.jp/togodb/view/taxonomy_icon_comment_en?species_id=149 ...

  12. The role of proboscis of the malaria vector mosquito Anopheles stephensi in host-seeking behavior

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    Yoshimura Aya

    2011-01-01

    Full Text Available Abstract Background The proboscis is an essential head appendage in insects that processes gustatory code during food intake, particularly useful considering that blood-sucking arthropods routinely reach vessels under the host skin using this proboscis as a probe. Results Here, using an automated device able to quantify CO2-activated thermo (35°C-sensing behavior of the malaria vector Anopheles stephensi, we uncovered that the protruding proboscis of mosquitoes contributes unexpectedly to host identification from a distance. Ablation experiments indicated that not only antennae and maxillary palps, but also proboscis were required for the identification of pseudo-thermo targets. Furthermore, the function of the proboscis during this behavior can be segregated from CO2 detection required to evoke mosquito activation, suggesting that the proboscis of mosquitoes divide the proboscis into a "thermo-antenna" in addition to a "thermo-probe". Conclusions Our findings support an emerging view with a possible role of proboscis as important equipment during host-seeking, and give us an insight into how these appendages likely evolved from a common origin in order to function as antenna organs.

  13. Laser dosimetry for disabling anopheles stephensi mosquitoes in-flight (Conference Presentation)

    Science.gov (United States)

    Keller, Matthew D.; Norton, Bryan J.; Rutschman, Phil; Farrar, David J.; Marvit, Maclen; Makagon, Artyom

    2016-03-01

    The Photonic Fence is a system designed to detect mosquitoes and other pestilent flying insects in an active region and to apply lethal doses of laser light to them. Previously, we determined lethal fluence levels for a variety of lasers and pulse conditions on anesthetized Anopheles stephensi mosquitoes. In this work, similar studies were performed while the bugs were freely flying within transparent cages. Dose-response curves were created for various beam diameter, pulse width, and power conditions at 455 nm, 532 nm, 1064nm, and 1540 nm wavelengths. Besides mortality outcomes, the flight behavior of the bugs and the performance of the tracking system were monitored for consistency and to ensure that they had no impact on the mortality outcomes. As in anesthetized experiments, the visible wavelengths required significantly less fluence than near infrared wavelengths to reliably disable bugs. For the visible wavelengths, lethal fluence values were generally equivalent to those found in anesthetized dosing, while near infrared wavelengths required approximately twice the fluence compared with anesthetized experiments. The performance of the optical tracking system remained highly stable throughout the experiments, and it was found not to influence mortality results for pulse widths up to 25 ms. In general, keeping energy constant while decreasing power and increasing pulse width reduced mortality levels. The results of this study further affirm the practicality of using optical approaches to protect people and crops from flying insects.

  14. Larvicidal and repellent properties of Adansonia digitata against medically important human malarial vector mosquito Anopheles stephensi (Diptera: Culicidae

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    K. Krishnappa , K. Elumalai , S. Dhanasekaran & J. Gokulakrishnan

    2012-06-01

    Full Text Available Background & objectives: Development of plant-based alternative compounds for mosquito control has gainedimportance now-a-days, in view of increasing resistance in mosquito vectors to existing insecticides. The larvicidaland repellent activities of benzene, chloroform, hexane and methanol leaf extracts of Indian medicinal plant,Adansonia digitata were investigated against malarial vector, Anopheles stephensi.Methods: In all, 25 III instar larvae of An. stephensi were exposed to various concentrations (30–180 mg/l in thelaboratory by using the standard protocol described by WHO (2005. The larvae were exposed for 24 h andmortalities were subjected to log-probit analysis. Repellent activity of crude leaf extract at the dosages of 2, 4and 6 mg/cm2 was evaluated in a net cage (45 × 30 × 45 cm containing 100 blood starved female mosquitoes ofAn. stephensi using the protocol of WHO (1996.Results: Preliminary phytochemical analysis of A. digitata showed the presence of triterpenoids and saponins.The LC50 and LC90 values of hexane, benzene, chloroform, and methanol extracts of A. digitata against An.stephensi larvae in 24 h were 111.32, 97.13, 88.55, 78.18 and 178.63, 176.19, 168.14, 155.42 mg/l, respectively.The repellent activity of methanol extract was found to be most effective and at higher concentration of 6mg/cm2 benzene, chloroform hexane and methanol extracts provided 100% protection up to 150, 180, 120 and210 min against An. stephensi, respectively.Conclusion: The preliminary study indicated that A. digitata showed larvicidal and repellent activities againstAn. stephensi and could be used for controlling mosquitoes. Further studies are indicated to purify the activecompounds from these plants for developing larvicide and repellents.

  15. Mosquito repellent potential ofPithecellobium dulce leaf and seed against malaria vectorAnopheles stephensi (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Mohan Rajeswary; Marimuthu Govindarajan

    2016-01-01

    Objective:To determine the repellent properties of hexane, benzene, ethyl acetate, chloroform and methanol extract ofPithecellobium dulce (P. dulce) leaf and seed against Anopheles stephensi(An. stephensi). Methods:Repellent activity assay was carried out in a net cage (45 cmí30 cmí25 cm) containing 100 blood starved female mosquitoes ofAn. stephensi. This assay was carried out in the laboratory conditions according to theWHO 2009 protocol. Plant crude extracts ofP. dulce were applied at 1.0, 2.5, and 5.0 mg/cm2 separately in the exposed fore arm of study subjects. Ethanol was used as the sole control. Results: In this study, the applied plant crude extracts were observed to protect against mosquito bites. There were no allergic reactions experienced by the study subjects. The repellent activity of the extract was dependent on the concentration of the extract. Among the tested solvents, the leaf and seed methanol extract showed the maximum efficacy. The highest concentration of 5.0 mg/cm2 leaf and seed methanol extract ofP. dulceprovided over 180 min and 150 min protection, respectively. Conclusions: Crude extracts ofP. dulceexhibit the potential for controlling malaria vector mosquitoAn. stephensi.

  16. Mosquito larvicidal properties of Impatiens balsamina (Balsaminaceae) against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Marimuthu Govindarajan; Mohan Rajeswary

    2014-01-01

    Objective: To assess the larvicidal potential of the crude benzene, chloroform, ethyl acetate and methanol solvent extracts of the medicinal plant Impatiens balsamina against Anopheles stephensi(An. stephensi), Aedes aegypti (Ae. aegypti) and Culex quinquefasciatus (Cx. quinquefasciatus). Methods: Twenty five third instar larvae of An. stephensi, Ae. aegypti and Cx. quinquefasciatus were exposed to various concentrations and were assayed in the laboratory by using the protocol recommended by WHO. The larval mortality was observed after 24 h of treatment. Results: Among extracts tested, the highest larvicidal activity was observed in leaf methanol extract of Impatiens balsamina against An. stephensi, Ae. aegypti and Cx. quinquefasciatus with the LC50 and LC90 values 98.04, 119.68, 125.06 and 172.93, 210.14, 220.60 mg/L, respectively. Conclusions:From the results it can be concluded that the larvicidal effect of Impatiens balsamina against An. stephensi, Ae. aegypti and Cx. quinquefasciatus make this plant product promising as an alternative to synthetic insecticide in mosquito control programs.

  17. Genetic Study of Propoxur Resistance—A Carbamate Insecticide in the Malaria Mosquito, Anopheles stephensi Liston

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    D. Sanil

    2010-01-01

    Full Text Available Anopheles stephensi Liston (Diptera: Culicidae is the urban vector of malaria in the Indian subcontinent and several countries of the Middle East. The genetics of propoxur resistance (pr in An. stephensi larvae was studied to determine its mode of inheritance. A diagnostic dose of 0.01 mg/L as recommended by WHO was used to establish homozygous resistant and susceptible strains. Reciprocal crosses between the resistant and susceptible strains showed an F1 generation of incomplete dominance. The progenies of backcrosses to susceptible parents were in 1 : 1 ratio of the same phenotypes as the parents and hybrids involved. The dosage mortality (d-m lines were constructed for each one of the crosses, and the degree of dominance was calculated. It is concluded that propoxur resistance in An. stephensi larvae is due to monofactorial inheritance with incomplete dominance and is autosomal in nature.

  18. Mosquito adulticidal and repellent activities of botanical extracts against malarial vector,Anopheles stephensi Liston (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Marimuthu Govindarajan; Rajamohan Sivakumar

    2011-01-01

    Objective:To determine the adulticidal and repellent activities of different solvent leaf extracts ofEclipta alba (E. alba) andAndrographis paniculata (A. paniculata)against malarial vector, Anopheles stephensi (An. stephensi).Methods:Adulticidal efficacy of the crude leaf extracts ofE. alba andA. paniculata with five different solvents like benzene, hexane, ethyl acetate, methanol and chloroform was tested against the five to six day old adult female mosquitoes of An. stephensi. The adult mortality was observed after24 h under the laboratory conditions. The repellent efficacy was determined againstAn. stephensimosquito species at three concentrations viz.,1.0, 2.5 and 5.0 mg/cm2 under laboratory conditions.Results: Among the tested solvents the maximum efficacy was observed in the methanol extract. TheLC50 andLC90 values ofE. alba andA. paniculata against adults ofAn. stephensiwere150.36, 130.19 ppm and285.22, 244.16ppm, respectively. No mortality was observed in controls. Thechi-square values were significant at P<0.05 level. Methanol extract of E. alba andA. paniculata was produce maximum repellency againstAn. stephensi.Conclusions:From the results it can be concluded the crude extract ofE. alba andA. paniculatawas an excellent potential for controllingAn. stephensimosquitoes.

  19. Effects of Anti-Mosquito Salivary Glands and Deglycosylated Midgut Antibodies of Anopheles stephensi on Fecundity and Longevity

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    H Mohammadzadeh Hajipirloo

    2005-09-01

    Full Text Available With the aim of controlling malaria by reducing vector population, the effects of antibodies produced against salivary glands and deglycosylated midgut antigens of Anopheles stephensi mosquitoes on fecundity and longevity of the same species were tested. Three deglycosylated preparations of midgut and two preparations of salivary glands were produced, conjugated with aluminum hydroxide gel, and subcutaneously injected to shoulders of TO (Turner Out-bred mice. After 4 immunizations and assurance of enough antibody production against utilized antigenic suspensions, effects of blood feeding on immunized and control mice were assayed. Insoluble preparation of midgut showed the strongest effect with 23.5% reduction in egg laying, and increasing death rate of vectors in third day after feeding. No significant reduction in fecundity or survivorship was seen with other preparations. Anopheles midgut insoluble antigens are potential candidates for designing vaccines against malaria vectors and further investigations need to be done to find effective antigens and the best way of their use.

  20. Mosquito Larvicidal Potential of Gossypium hirsutum (Bt cotton Leaves Extracts against Aedes aegypti and Anopheles stephensi larvae.

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    Chandrashekhar D Patil

    2014-06-01

    Full Text Available We aimed to extract the ingredients from leaves of Gossypium hirsutum (Bt cotton using different solvents and evaluate for potential use to control different larval stages of mosquito species, Aedes aegypti and Anopheles stephensi.Qualitative and quantitative estimation of ingredients from Go. hirsutum (Bt plant extract was carried out and their inhibitory action against mosquito larvae was determined using mosquito larvicidal assay.LC50 values of water, ethanol, ethyl acetate and hexane extracts for Ae. aegypti were 211.73±21.49, 241.64±19.92, 358.07±32.43, 401.03±36.19 and 232.56±26.00, 298.54±21.78, 366.50±30.59, 387.19±31.82 for 4(th instar of An. stephensi, respectively. The water extract displayed lowest LC50 value followed by ethanol, ethyl acetate and hexane. Owing to the comparatively better activity of water extract, its efficacy was further evaluated for mosquito larvicidal activity, which exhibited LC50 values of 133.95±12.79, 167.65±11.34 against 2(nd and 3(rd instars of Ae. aegypti and 145.48±11.76, 188.10±12.92 against 2(nd and 3(rd instars of An. stephensi, respectively. Crude protein from the water extract was precipitated using acetone and tested against 2(nd, 3(rd and 4(th instars of Ae. aegypti and An. stephensi. It revealed further decrease in LC50 values as 105.72±25.84, 138.23±23.18, 126.19±25.65, 134.04±04 and 137.88±17.59, 154.25±16.98 for 2(nd, 3(rd and 4(th instars of Ae. aegypti and An. stephensi, respectively.Leaves extracts of Go. hirsutum (Bt is potential mosquito larvicide and can be used as a potent alternative to chemical insecticides in integrated pest management.

  1. Mitochondrial NAD+-dependent malic enzyme from Anopheles stephensi: a possible novel target for malaria mosquito control

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    Pon Jennifer

    2011-10-01

    Full Text Available Abstract Background Anopheles stephensi mitochondrial malic enzyme (ME emerged as having a relevant role in the provision of pyruvate for the Krebs' cycle because inhibition of this enzyme results in the complete abrogation of oxygen uptake by mitochondria. Therefore, the identification of ME in mitochondria from immortalized A. stephensi (ASE cells and the investigation of the stereoselectivity of malate analogues are relevant in understanding the physiological role of ME in cells of this important malaria parasite vector and its potential as a possible novel target for insecticide development. Methods To characterize the mitochondrial ME from immortalized ASE cells (Mos. 43; ASE, mass spectrometry analyses of trypsin fragments of ME, genomic sequence analysis and biochemical assays were performed to identify the enzyme and evaluate its activity in terms of cofactor dependency and inhibitor preference. Results The encoding gene sequence and primary sequences of several peptides from mitochondrial ME were found to be highly homologous to the mitochondrial ME from Anopheles gambiae (98% and 59% homologous to the mitochondrial NADP+-dependent ME isoform from Homo sapiens. Measurements of ME activity in mosquito mitochondria isolated from ASE cells showed that (i Vmax with NAD+ was 3-fold higher than that with NADP+, (ii addition of Mg2+ or Mn2+ increased the Vmax by 9- to 21-fold, with Mn2+ 2.3-fold more effective than Mg2+, (iii succinate and fumarate increased the activity by 2- and 5-fold, respectively, at sub-saturating concentrations of malate, (iv among the analogs of L-malate tested as inhibitors of the NAD+-dependent ME catalyzed reaction, small (2- to 3-carbons organic diacids carrying a 2-hydroxyl/keto group behaved as the most potent inhibitors of ME activity (e.g., oxaloacetate, tartronic acid and oxalate. Conclusions The biochemical characterization of Anopheles stephensi ME is of critical relevance given its important role in

  2. Mosquito larvicidal and biting deterrency activity of bud of Polianthes tuberosa plants extract against Anopheles stephensi and Culex quinquefasciatus.

    Science.gov (United States)

    Anjali, Rawani; Atanu, Banerjee; Goutam, Chandra

    2012-06-01

    Mosquito control by phytochemicals is an alternative method to synthetic insecticides, as it is biodegradable and non resistant to vector mosquito. Polianthes tuberosa is a perennial plant distributed in many parts of India. The present study was undertaken to scientifically evaluate the larvicide and biting deterrency activity of bud of Polianthes tuberosa against Culex quinquefasciatus and Anopheles stephensi. Crude and solvent extract [ethyl acetate, chloroform: methanol (1:1, v/v), acetone] of fresh, mature, bud of P. tuberosa was tested against (ex. quinquefasciatus and An. stephensi. The repellent activity tested by chloroform: methanol (1:1, v/v) solvent extract against both mosquito species. The appropriate lethal concentrations at 24h for chloroform: methanol (1:1, v/v) extract was also studied on non target organisms such as Toxorhynchites larvae, Diplonychus annulatum and Chironomus circumdatus. In a 72 hour bioassay experiment, 0.5% crude extract showed the highest mortality and chloroform: methanol (1:1, v/v) solvent extract showed the highest mortality, the maximum (p larvicide agent. There is no changes in the activity non-target organism so, it is safe to use.

  3. Effect of anti-mosquito hemolymph antibodies on fecundity and on the infectivity of malarial parasite Plasmodium vivax to Anopheles stephensi (Diptera:Insecta).

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    Gulia, Monika; Suneja, Amita; Gakhar, Surendra K

    2002-06-01

    Rabbit antibodies to hemolymph antigens (102.5, 101, 100, 96, 88, 80, 64, 55, 43, 29, and 23 kDa) of Anopheles stephensi reduced fecundity as well as viability in An. stephensi. However, ingestion of these antibodies was not associated with a marked effect on the engorgement of mosquitoes but egg laying was significantly delayed. Antisera raised against hemolymph proteins were also used to identify cross reactive antigens/epitopes present in other tissues by Western blotting, as well as by in vivo ELISA. In addition, a significant reduction in oocyst development was also observed in An. stephensi mosquitoes that ingested anti-hemolymph antibodies along with Plasmodium vivax. The results confirmed the feasibility of targeting mosquito antigens as a novel anti-mosquito strategy, as well as confirmed the usefulness of such antigens for the development of a transmission-blocking vaccine. PMID:12195047

  4. Mosquito larvicidal properties of volatile oil from salt marsh mangrove plant of Sesuvium portulacastrum against Anopheles stephensi and Aedes aegypti

    Institute of Scientific and Technical Information of China (English)

    Mohamed Yacoob Syed Ali; Venkatraman Anuradha; SyedAbudhair Sirajudeen; Prathasarathy Vijaya; Nagarajan Yogananth; Ramachandran Rajan; Peer Mohamed Kalitha Parveen

    2013-01-01

    Objective: To identify the larvicidal activity of the volatile oil from Sesuvium portulacastrum (S.portulacastrum ) against Anopheles stephensi and Aedes aegypti. Methods: Volatile oil extract of S. portulacastrum was prepared in a graded series of concentration. The test for the larvicidal effect of volatile oil against mosquitos larvae was conducted in accordance with the WHO standard method. Batches of 25 early 4th instar larvae of two mosquitoes were transferred to 250 mL enamel bowl containing 199 mL of distilled water and 1 mL of plant extracts. Each experiment was conducted with triplicate with concurrent a control group.Results:Volatile oil extract of S. portulacastrum showed toxicity against 4th instar larvae of Aedes aegypti and Anopheles stephensi with equivalent LC50 value [(63±7.8) µL/mL, LCL-UCL=55.2-64.0] and LC90 value [(94.2±3.9) µL/mL)] in maximum activity with minimum concentration (200 µL/mL) of volatile oil and followed by maximum activity of 250 µL concentration showed LC50 value=(68.0±8.2) µL/mL, LCL-UCL=66.26-69.2 and LC50 value of (55.2±2.8) µL/mL, LCL-UCL=53.7-56.9, LC90=(95.2±1.25) µL/mL and followed by 250 µL of oil extract against 4th instar larvae of Aedes aegypti respectively.Conclusions:It is inferred from the present study that, the extracts from salt marsh mangrove plan of S. portulacastum are identified as a potential source of safe and efficacious mosquito control agents for the management of vector borne diseases of malaria and dengue.

  5. Evaluation of some aromatic plant extracts for mosquito larvicidal potential against Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi.

    Science.gov (United States)

    Jayaraman, M; Senthilkumar, A; Venkatesalu, V

    2015-04-01

    In the present investigation, larvicidal potential of hexane, choloroform, ethyl acetate, acetone, and methanol extracts of seven aromatic plants, viz., Blumea mollis, Chloroxylon swietenia, Clausena anisata, Feronia limnonia, Lantana camera, Plectranthus amboinicus, and Tagetes erecta were screened against Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi. The larval mortality was observed after 12 and 24 h of exposure period. The results revealed that all the extracts showed varied levels of larvicidal activity against the mosquito species tested. However, the ethyl acetate extract of Chloroxylon swietenia showed the remarkable larvicidal activity against C. quinquefasciatus, Ae. aegypti, and An. stephensi. After 12 h of exposure period, the larvicidal activity was LC50 = 194.22 and LC90 = 458.83 ppm (C. quinquefasciatus), LC50 = 173.04 and LC90 = 442.73 ppm (Ae. aegypti), and LC50 = 167.28 and LC90 = 433.07 ppm (An. stephensi), and the larvicidal activity after 24-h exposure period was LC50 = 94.12 and LC90 = 249.83 ppm (C. quinquefasciatus), LC50 = 80.58 and LC90 = 200.96 ppm (Ae. aegypti), and LC50 = 76.24 and LC90 = 194.51 ppm (An. stephensi). The larvicidal potential of other plant extracts were in order of ethyl acetate extract of Clausena anisata > methanol extract of P. amboinicus > acetone extract of F. limonia > methanol extract of T. erecta > methanol extract of B. mollis > and methanol extract of L. camera. The results of the present study offer a possible way for further investigations to find out the active molecule responsible for the activity. PMID:25630696

  6. Plasmodium falciparum malaria challenge by the bite of aseptic Anopheles stephensi mosquitoes: results of a randomized infectivity trial.

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    Kirsten E Lyke

    Full Text Available BACKGROUND: Experimental infection of malaria-naïve volunteers by the bite of Plasmodium falciparum-infected mosquitoes is a preferred means to test the protective effect of malaria vaccines and drugs. The standard model relies on the bite of five infected mosquitoes to induce malaria. We examined the efficacy of malaria transmission using mosquitoes raised aseptically in compliance with current Good Manufacturing Practices (cGMPs. METHODS AND FINDINGS: Eighteen adults aged 18-40 years were randomized to receive 1, 3 or 5 bites of Anopheles stephensi mosquitoes infected with the chloroquine-sensitive NF54 strain of P. falciparum. Seventeen participants developed malaria; fourteen occurring on Day 11. The mean prepatent period was 10.9 days (9-12 days. The geometric mean parasitemia was 15.7 parasites/µL (range: 4-70 by microscopy. Polymerase chain reaction (PCR detected parasites 3.1 (range: 0-4 days prior to microscopy. The geometric mean sporozoite load was 16,753 sporozoites per infected mosquito (range: 1,000-57,500. A 1-bite participant withdrew from the study on Day 13 post-challenge and was PCR and smear negative. CONCLUSIONS: The use of aseptic, cGMP-compliant P. falciparum-infected mosquitoes is safe, is associated with a precise prepatent period compared to the standard model and appears more efficient than the standard approach, as it led to infection in 100% (6/6 of volunteers exposed to three mosquito bites and 83% (5/6 of volunteers exposed to one mosquito bite. TRIAL REGISTRATION: ClinicalTrials.gov NCT00744133.

  7. Cuticular hydrocarbon discrimination/variation among strains of the mosquito, Anopheles (Cellia) stephensi Liston.

    Science.gov (United States)

    Anyanwu, G I; Davies, D H; Molyneux, D H; Phillips, A; Milligan, P J

    1993-06-01

    Cuticular lipids were removed from adult female Anopheles stephensi Liston and the hydrocarbons present were separated and quantified by gas chromatography. Comparison was made between the hydrocarbons of four An. stephensi strains: Russ, sensitive to DDT and malathion and originally isolated in the former U.S.S.R.; Beech, a DDT-resistant Indian strain with high sensitivity to Plasmodium species; St Mal, a strain from Pakistan shown to be resistant to malathion; and Iraq, a DDT-susceptible strain from Iraq. Discriminant analysis indicated that the four groups were distinct and that, on average, 78% of the population could be separated on the basis of the quantities of some of the cuticular hydrocarbons. The profiles of Beech and Russ or Russ and St Mal could be separated in 98% of the cases. There was reduced segregation between the profiles of St. Mal and Iraq, suggesting greater similarity in the hydrocarbons of these two strains. The usefulness of cuticular hydrocarbon in determining species relationships is discussed. PMID:8257238

  8. Susceptibility of Anopheles stephensi to Plasmodium gallinaceum: a trait of the mosquito, the parasite, and the environment.

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    Jen C C Hume

    Full Text Available BACKGROUND: Vector susceptibility to Plasmodium infection is treated primarily as a vector trait, although it is a composite trait expressing the joint occurrence of the parasite and the vector with genetic contributions of both. A comprehensive approach to assess the specific contribution of genetic and environmental variation on "vector susceptibility" is lacking. Here we developed and implemented a simple scheme to assess the specific contributions of the vector, the parasite, and the environment to "vector susceptibility." To the best of our knowledge this is the first study that employs such an approach. METHODOLOGY/PRINCIPAL FINDINGS: We conducted selection experiments on the vector (while holding the parasite "constant" and on the parasite (while holding the vector "constant" to estimate the genetic contributions of the mosquito and the parasite to the susceptibility of Anopheles stephensi to Plasmodium gallinaceum. We separately estimated the realized heritability of (i susceptibility to parasite infection by the mosquito vector and (ii parasite compatibility (transmissibility with the vector while controlling the other. The heritabilities of vector and the parasite were higher for the prevalence, i.e., fraction of infected mosquitoes, than the corresponding heritabilities of parasite load, i.e., the number of oocysts per mosquito. CONCLUSIONS: The vector's genetics (heritability comprised 67% of "vector susceptibility" measured by the prevalence of mosquitoes infected with P. gallinaceum oocysts, whereas the specific contribution of parasite genetics (heritability to this trait was only 5%. Our parasite source might possess minimal genetic diversity, which could explain its low heritability (and the high value of the vector. Notably, the environment contributed 28%. These estimates are relevant only to the particular system under study, but this experimental design could be useful for other parasite-host systems. The prospects and

  9. Chromosomal inversions among insecticide-resistant strains of Anopheles stephensi Liston, a malaria mosquito.

    Science.gov (United States)

    Shetty, N J; Hariprasad, T P N; Sanil, D; Zin, T

    2013-11-01

    Polytene chromosomes were prepared from the ovarian nurse cells of semi-gravid females of ten insecticide-resistant strains of Anopheles stephensi. Altogether, 16 heterozygous paracentric inversions, namely b/+ (11D-16C) in alphamethrin; i/+ (14B-18A) and h/+ (27B-28A) in DDT; j/+ (14A-16B) in chlorpyrifos; k/+ (11D-16B) in cyfluthrin; l/+ (11A-16C) in deltamethrin; m/+ (14B-15C) and e/+ (32A-33B) in bifenthrin; n/+ (12D-14B), f/+ (33A-36A) and g/+ (33C-34A) in propoxur; o/+ (11A-12D), h/+ (37A-37C) and i/+ (31C-32C) in temephos; d/+ (33D-35C) in carbofuran and a/+ (41C-43B) in neem strains, were reported. No inversions were observed in X chromosome so far. The frequency of inversions in different insecticides was found to be highest in the 2R arm, followed by the 3R arm. Such inversions were not reported in the corresponding susceptible strains or in the parental stocks. PMID:23982309

  10. Molecular interactions between Anopheles stephensi midgut cells and Plasmodium berghei: the time bomb theory of ookinete invasion of mosquitoes.

    Science.gov (United States)

    Han, Y S; Thompson, J; Kafatos, F C; Barillas-Mury, C

    2000-11-15

    We present a detailed analysis of the interactions between Anopheles stephensi midgut epithelial cells and Plasmodium berghei ookinetes during invasion of the mosquito by the parasite. In this mosquito, P. berghei ookinetes invade polarized columnar epithelial cells with microvilli, which do not express high levels of vesicular ATPase. The invaded cells are damaged, protrude towards the midgut lumen and suffer other characteristic changes, including induction of nitric oxide synthase (NOS) expression, a substantial loss of microvilli and genomic DNA fragmentation. Our results indicate that the parasite inflicts extensive damage leading to subsequent death of the invaded cell. Ookinetes were found to be remarkably plastic, to secrete a subtilisin-like serine protease and the GPI-anchored surface protein Pbs21 into the cytoplasm of invaded cells, and to be capable of extensive lateral movement between cells. The epithelial damage inflicted is repaired efficiently by an actin purse-string-mediated restitution mechanism, which allows the epithelium to 'bud off' the damaged cells without losing its integrity. A new model, the time bomb theory of ookinete invasion, is proposed and its implications are discussed. PMID:11080150

  11. Successful human infection with P. falciparum using three aseptic Anopheles stephensi mosquitoes: a new model for controlled human malaria infection.

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    Matthew B Laurens

    Full Text Available Controlled human malaria infection (CHMI is a powerful method for assessing the efficacy of anti-malaria vaccines and drugs targeting pre-erythrocytic and erythrocytic stages of the parasite. CHMI has heretofore required the bites of 5 Plasmodium falciparum (Pf sporozoite (SPZ-infected mosquitoes to reliably induce Pf malaria. We reported that CHMI using the bites of 3 PfSPZ-infected mosquitoes reared aseptically in compliance with current good manufacturing practices (cGMP was successful in 6 participants. Here, we report results from a subsequent CHMI study using 3 PfSPZ-infected mosquitoes reared aseptically to validate the initial clinical trial. We also compare results of safety, tolerability, and transmission dynamics in participants undergoing CHMI using 3 PfSPZ-infected mosquitoes reared aseptically to published studies of CHMI using 5 mosquitoes. Nineteen adults aged 18-40 years were bitten by 3 Anopheles stephensi mosquitoes infected with the chloroquine-sensitive NF54 strain of Pf. All 19 participants developed malaria (100%; 12 of 19 (63% on Day 11. The mean pre-patent period was 258.3 hours (range 210.5-333.8. The geometric mean parasitemia at first diagnosis by microscopy was 9.5 parasites/µL (range 2-44. Quantitative polymerase chain reaction (qPCR detected parasites an average of 79.8 hours (range 43.8-116.7 before microscopy. The mosquitoes had a geometric mean of 37,894 PfSPZ/mosquito (range 3,500-152,200. Exposure to the bites of 3 aseptically-raised, PfSPZ-infected mosquitoes is a safe, effective procedure for CHMI in malaria-naïve adults. The aseptic model should be considered as a new standard for CHMI trials in non-endemic areas. Microscopy is the gold standard used for the diagnosis of Pf malaria after CHMI, but qPCR identifies parasites earlier. If qPCR continues to be shown to be highly specific, and can be made to be practical, rapid, and standardized, it should be considered as an alternative for diagnosis

  12. Mosquito larvicidal properties ofOrthosiphon thymiflorus(Roth) Sleesen. (Family:Labiatae) against mosquito vectors,Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    K Kovendan; K Murugan; S Vincent; Donald R Barnard

    2012-01-01

    ABSTRACT Objective:To determine the mosquito larvicidal activities of hexane, chloroform, ethyl acetate, acetone and methanol leaf extract ofOrthosiphon thymiflorus (O. thymiflorus) againstAnopheles stephensi (An. stephensi), Culex quinquefasciatus (Cx. quinquefasciatus) andAedes aegypti (Ae. aegypti).Methods: The larvicidal activity was assayed against three mosquito species at various concentrations ranging from (50-450 ppm) under the laboratory conditions. TheLC50and LC90value of theO. thymiflorus leaf extract was determined by Probit analysis.Results: The LC50values of hexane, chloroform, ethyl acetate, acetone and methanol extract ofO. thymiflorus third instar larvae ofAn. stephensiwereLC50= 201.39, 178.76, 158.06, 139.22 and118.74 ppm;Cx. quinquefasciatus were LC50=228.13, 209.72, 183.35, 163.55 and149.96 ppm andAe. aegyptiwere LC50=215.65, 197.91, 175.05, 154.80 and137.26 ppm, respectively. Maximum larvicidal activity was observed in the methanolic extract followed by acetone, ethyl acetate chloroform and hexane extract. The larval mortality was observed after24h exposure. No mortality was observed in control.Conclusions:The present results suggest that the effective plant crude extracts have potential to be used as an ideal eco-friendly approach for the control of mosquito vectors. This study provides the first report on the larvicidal activity of this plant crude solvent extract of againstAn. stephensi, Cx. quinquefasciatus andAe. aegyptimosquitoes.

  13. Effect of leaf essential oil ofCoccinia indica on egg hatchability and different larval instars of malarial mosquito Anopheles stephensi

    Institute of Scientific and Technical Information of China (English)

    Sankaran Rajkumar; Arulsamy Jebanesan; Rajarathinavelu Nagarajan

    2011-01-01

    Objective:To assess the larvicidal and egg hatching inhibition property of the leaf essential oil ofCoccinia indica (C. indica) againstAnopheles stephensi (An. stephensi).Methods:The larvicidal potential ofC.indica leaf essential oil was evaluated against 1st,2nd,3rd and4th instars larvae ofAn. stephensi usingWHOprotocol. The24hLC50 andLC90values of the essential oil were determined following probit analysis. The egg hatching inhibition activity was also tested at10, 20, 40, and60 mg/L. TheIC50 value of essential oil was determined against eggs ofAn. stephensi.Results: The essential oil extracted fromC. indica possessed excellent larvicidal and egg hatching inhibition activity against An. stephensi. The bioassays showedLC50-LC90 of54.3-140.3,65.5-155.6, 86.8-180.7 and95.3-192.6 for 1st,2nd,3rd, and 4th larval instars, respectively. The50% egg hatching inhibition concentration(IC50) was noted at16.5mg/L.Conclusions: The present finding suggest that theC. indica leaf essential oil provided an excellent potential for controllingAn. stephensi mosquito at earlier stage of their life cycle.

  14. Ovicidal, larvicidal and adulticidal properties of Asparagus racemosus (Willd.) (Family: Asparagaceae) root extracts against filariasis (Culex quinquefasciatus), dengue (Aedes aegypti) and malaria (Anopheles stephensi) vector mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Govindarajan, Marimuthu; Sivakumar, Rajamohan

    2014-04-01

    Several diseases are associated to the mosquito-human interaction. Mosquitoes are the carriers of severe and well-known illnesses such as malaria, arboviral encephalitis, dengue fever, chikungunya fever, West Nile virus and yellow fever. These diseases produce significant morbidity and mortality in humans and livestock around the world. The present investigation was undertaken to study the ovicidal, larvicidal and adulticidal activities of crude hexane, ethyl acetate, benzene, chloroform and methanol extracts of root of Asparagus racemosus were assayed for their toxicity against three important vector mosquitoes, viz., Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi (Diptera: Culicidae). The mean percent hatchability of the eggs was observed after 48 h post-treatment. The percent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. All the five solvent extracts showed moderate ovicidal activity; however, the methanol extract showed the highest ovicidal activity. The methanol extract of Asparagus racemosus against Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi exerted 100% mortality (zero hatchability) at 375, 300 and 225 ppm, respectively. Control eggs showed 99-100% hatchability. The larval mortality was observed after 24 h of exposure. All extracts showed moderate larvicidal effects; however, the highest larval mortality was found in methanol extract of root of Asparagus racemosus against the larvae of Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi with the LC50 and LC90 values were 115.13, 97.71 and 90.97 ppm and 210.96, 179.92, and 168.82 ppm, respectively. The adult mortality was observed after 24 h recovery period. The plant crude extracts showed dose-dependent mortality. At higher concentrations, the adult showed restless movement for some times with abnormal wagging and then died. Among the extracts tested, the highest adulticidal activity was observed in

  15. Insecticidal potency of Aspergillus terreus against larvae and pupae of three mosquito species Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti.

    Science.gov (United States)

    Ragavendran, Chinnasamy; Natarajan, Devarajan

    2015-11-01

    Microbial control agents offer alternatives to chemical pest control, as they can be more selective than chemical insecticides. The present study evaluates the mosquito larvicidal and pupicidal potential of fungus mycelia using ethyl acetate and methanol solvent extracts produced by Aspergillus terreus against Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti. The A. terreus mycelia were extracted after 15 days from Sabouraud dextrose broth medium. The ethyl acetate extracts showed lethal concentration that kills 50% of the exposed larvae (LC50) and lethal concentration that kills 90% of the exposed larvae (LC90) values of the first, second, third, and fourth instar larvae of An. stephensi (LC50 = 97.410, 102.551, 29.802, and 8.907; LC90 = 767.957, 552.546, 535.474, and 195.677 μg/ml), Cx. quinquefasciatus (LC50 = 89.584, 74.689, 68.265, and 67.40; LC90 = 449.091, 337.355, 518.793, and 237.347 μg/ml), and Ae. aegypti (LC50 = 83.541, 84.418, 80.407, and 95.926; LC90 = 515.464, 443.167, 387.910, and 473.998 μg/ml). Pupicidal activity of mycelium extracts was tested against An. stephensi (LC50 = 25.228, LC90 = 140.487), Cx. quinquefasciatus (LC50 = 54.525, LC90 = 145.366), and Ae. aegypti (LC50 = 10.536, LC90 = 63.762 μg/ml). At higher concentration (500 μg/ml), mortality starts within the first 6 h of exposure. One hundred percent mortality occurs at 24-h exposure. The overall result observed that effective activity against selected mosquito larvae and pupae after 24 h was a dose and time-dependent activity. These ensure that the resultant mosquito population reduction is substantial even where the larvicidal and pupicidal potential is minimal. The FTIR spectra of ethyl acetate extract reflect prominent peaks (3448.32, 3000.36, 2914.59, 2118.73, 1668.21, 1436.87, 1409.02, 954.33, 901.13, and 704.67 cm(-1)). The spectra showed a sharp absorption band at 1314.66 cm(-1) assigned to wagging vibration of

  16. Insecticidal potency of Aspergillus terreus against larvae and pupae of three mosquito species Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti.

    Science.gov (United States)

    Ragavendran, Chinnasamy; Natarajan, Devarajan

    2015-11-01

    Microbial control agents offer alternatives to chemical pest control, as they can be more selective than chemical insecticides. The present study evaluates the mosquito larvicidal and pupicidal potential of fungus mycelia using ethyl acetate and methanol solvent extracts produced by Aspergillus terreus against Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti. The A. terreus mycelia were extracted after 15 days from Sabouraud dextrose broth medium. The ethyl acetate extracts showed lethal concentration that kills 50% of the exposed larvae (LC50) and lethal concentration that kills 90% of the exposed larvae (LC90) values of the first, second, third, and fourth instar larvae of An. stephensi (LC50 = 97.410, 102.551, 29.802, and 8.907; LC90 = 767.957, 552.546, 535.474, and 195.677 μg/ml), Cx. quinquefasciatus (LC50 = 89.584, 74.689, 68.265, and 67.40; LC90 = 449.091, 337.355, 518.793, and 237.347 μg/ml), and Ae. aegypti (LC50 = 83.541, 84.418, 80.407, and 95.926; LC90 = 515.464, 443.167, 387.910, and 473.998 μg/ml). Pupicidal activity of mycelium extracts was tested against An. stephensi (LC50 = 25.228, LC90 = 140.487), Cx. quinquefasciatus (LC50 = 54.525, LC90 = 145.366), and Ae. aegypti (LC50 = 10.536, LC90 = 63.762 μg/ml). At higher concentration (500 μg/ml), mortality starts within the first 6 h of exposure. One hundred percent mortality occurs at 24-h exposure. The overall result observed that effective activity against selected mosquito larvae and pupae after 24 h was a dose and time-dependent activity. These ensure that the resultant mosquito population reduction is substantial even where the larvicidal and pupicidal potential is minimal. The FTIR spectra of ethyl acetate extract reflect prominent peaks (3448.32, 3000.36, 2914.59, 2118.73, 1668.21, 1436.87, 1409.02, 954.33, 901.13, and 704.67 cm(-1)). The spectra showed a sharp absorption band at 1314.66 cm(-1) assigned to wagging vibration of

  17. Insecticidal potential of Ocimum canum plant extracts against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus larval and adult mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Murugan, Jimmantiyur Madhappan; Ramkumar, Govindaraju; Shivakumar, Muthugoundar Subramanian

    2016-01-01

    Mosquitoes have developed resistance to various synthetic insecticides, making their control increasingly difficult. Insecticides of botanical origin may serve as suitable natural control. This study evaluates the toxic potential of Ocimum canum (Sims) leaf extract and powder against Anopheles stephensi (Liston), Aedes aegypti (Lin) and Culex quinquefasciatus (Say) larval and adult mosquitoes. Larval mortality was observed after 24 h recovery period and adult smoke toxicity observed for 40 min duration at 10 min interval. Methanol extract of O. canum showed highest larval mortality against the larvae of C. quinquefasciatus LC50 = 28.3225, LC90 = 44.1150; Ae. aegypti LC50 = 43.327, LC90 = 61.249; and An. stephensi LC50 = 30.2001, LC90 = 48.2866 ppm. The smoke toxicities were 93% mortality in C. quinquefasciatus, 74% in Ae. aegypti and 79% in An. stephensi adults, respectively, whereas 100% mortality was recorded in the commercial mosquito control. Our results suggest that O. canum leaf extract and powder are natural insecticide, and ideal eco friendly approach for mosquito control.

  18. Highly efficient Cas9-mediated gene drive for population modification of the malaria vector mosquito Anopheles stephensi.

    Science.gov (United States)

    Gantz, Valentino M; Jasinskiene, Nijole; Tatarenkova, Olga; Fazekas, Aniko; Macias, Vanessa M; Bier, Ethan; James, Anthony A

    2015-12-01

    Genetic engineering technologies can be used both to create transgenic mosquitoes carrying antipathogen effector genes targeting human malaria parasites and to generate gene-drive systems capable of introgressing the genes throughout wild vector populations. We developed a highly effective autonomous Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-associated protein 9 (Cas9)-mediated gene-drive system in the Asian malaria vector Anopheles stephensi, adapted from the mutagenic chain reaction (MCR). This specific system results in progeny of males and females derived from transgenic males exhibiting a high frequency of germ-line gene conversion consistent with homology-directed repair (HDR). This system copies an ∼ 17-kb construct from its site of insertion to its homologous chromosome in a faithful, site-specific manner. Dual anti-Plasmodium falciparum effector genes, a marker gene, and the autonomous gene-drive components are introgressed into ∼ 99.5% of the progeny following outcrosses of transgenic lines to wild-type mosquitoes. The effector genes remain transcriptionally inducible upon blood feeding. In contrast to the efficient conversion in individuals expressing Cas9 only in the germ line, males and females derived from transgenic females, which are expected to have drive component molecules in the egg, produce progeny with a high frequency of mutations in the targeted genome sequence, resulting in near-Mendelian inheritance ratios of the transgene. Such mutant alleles result presumably from nonhomologous end-joining (NHEJ) events before the segregation of somatic and germ-line lineages early in development. These data support the design of this system to be active strictly within the germ line. Strains based on this technology could sustain control and elimination as part of the malaria eradication agenda. PMID:26598698

  19. Production of a Transgenic Mosquito Expressing Circumsporozoite Protein, a Malarial Protein, in the Salivary Gland of Anopheles stephensi (Diptera:Culicidae

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    Matsuoka,Hiroyuki

    2010-08-01

    Full Text Available We are producing a transgenic mosquito, a flying syringe, to deliver a vaccine protein to human beings via the saliva the mosquito deposits in the skin while biting. The mosquito produces a vaccine protein in the salivary gland (SG and deposits the protein into the host's skin when it takes the host's blood. We chose circumsporozoite protein (CSP, currently the most promising malaria vaccine candidate, to be expressed in the SG of Anopheles stephensi. To transform the mosquitoes, plasmid containing the CSP gene under the promoter of female SG-specific gene, as well as the green fluorescent protein (GFP gene under the promoter of 3xP3 as a selection marker in the eyes, was injected into more than 400 eggs. As a result, five strains of GFP-expressing mosquitoes were established, and successful CSP expression in the SG was confirmed in one strain. The estimated amount of CSP in the SG of the strain was 40ng per mosquito. We allowed the CSP-expressing mosquitoes to feed on mice to induce the production of anti-CSP antibody. However, the mice did not develop anti-CSP antibody even after transgenic mosquitoes had bitten them several times. We consider that CSP in the SG was not secreted properly into the saliva. Further techniques and trials are required in order to realize vaccine-delivering mosquitoes.

  20. Suppressor of hairy-wing, modifier of mdg4 and centrosomal protein of 190 gene orthologues of the gypsy insulator complex in the malaria mosquito, Anopheles stephensi.

    Science.gov (United States)

    Carballar-Lejarazú, R; Brennock, P; James, A A

    2016-08-01

    DNA insulators organize independent gene regulatory domains and can regulate interactions amongst promoter and enhancer elements. They have the potential to be important in genome enhancing and editing technologies because they can mitigate chromosomal position effects on transgenes. The orthologous genes of the Anopheles stephensi putative gypsy-like insulator protein complex were identified and expression characteristics studied. These genes encode polypeptides with all the expected protein domains (Cysteine 2 Histidine 2 (C2H2) zinc fingers and/or a bric-a-brac/poxvirus and zinc finger). The mosquito gypsy transcripts are expressed constitutively and are upregulated in ovaries of blood-fed females. We have uncovered significant experimental evidence that the gypsy insulator protein complex is widespread in vector mosquitoes.

  1. Suppressor of hairy-wing, modifier of mdg4 and centrosomal protein of 190 gene orthologues of the gypsy insulator complex in the malaria mosquito, Anopheles stephensi.

    Science.gov (United States)

    Carballar-Lejarazú, R; Brennock, P; James, A A

    2016-08-01

    DNA insulators organize independent gene regulatory domains and can regulate interactions amongst promoter and enhancer elements. They have the potential to be important in genome enhancing and editing technologies because they can mitigate chromosomal position effects on transgenes. The orthologous genes of the Anopheles stephensi putative gypsy-like insulator protein complex were identified and expression characteristics studied. These genes encode polypeptides with all the expected protein domains (Cysteine 2 Histidine 2 (C2H2) zinc fingers and/or a bric-a-brac/poxvirus and zinc finger). The mosquito gypsy transcripts are expressed constitutively and are upregulated in ovaries of blood-fed females. We have uncovered significant experimental evidence that the gypsy insulator protein complex is widespread in vector mosquitoes. PMID:27110891

  2. Resistance Status of the Malaria Vector Mosquitoes, Anopheles stephensi and Anopheles subpictus Towards Adulticides and Larvicides in Arid and Semi-Arid Areas of India

    OpenAIRE

    Tikar, S. N.; M J Mendki; Sharma, A K; D. Sukumaran; Veer, Vijay; Prakash, Shri; Parashar, B. D.

    2011-01-01

    Susceptibility studies of malaria vectors Anopheles stephensi Liston (Diptera: Culicidae) and An. subpictus Grassi collected during 2004–2007 from various locations of Arid and Semi-Arid Zone of India were conducted by adulticide bioassay of DDT, malathion, deltamethrin and larvicide bioassay of fenthion, temephos, chlorpyriphos and malathion using diagnostic doses. Both species from all locations exhibited variable resistance to DDT and malathion from majority of location. Adults of both the...

  3. Mosquito larvicidal potential of silver nanoparticles synthesized using Chomelia asiatica (Rubiaceae) against Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus (Diptera: Culicidae).

    Science.gov (United States)

    Muthukumaran, Udaiyan; Govindarajan, Marimuthu; Rajeswary, Mohan

    2015-03-01

    Mosquitoes transmit serious human diseases, causing millions of deaths every year. Mosquito control is to enhance the health and quality of life of county residents and visitors through the reduction of mosquito populations. Mosquito control is a serious concern in developing countries like India due to the lack of general awareness, development of resistance, and socioeconomic reasons. Today, nanotechnology is a promising research domain which has a wide ranging application in vector control programs. These are nontoxic, easily available at affordable prices, biodegradable, and show broad-spectrum target-specific activities against different species of vector mosquitoes. In the present study, larvicidal activity of aqueous leaf extract and silver nanoparticles (AgNPs) synthesized using C. asiatica plant leaves against late third instar larvae of Anopheles stephensi, Aedes aegypti, and Cx. quinquefasciatus. The range of varying concentrations of synthesized AgNPs (8, 16, 24, 32, and 40 μg/mL) and aqueous leaf extract (40, 80, 120, 160, and 200 μg/mL) were tested against the larvae of An. stephensi, Ae. aegypti, and Cx. quinquefasciatus. The synthesized AgNPs from C. asiatica were highly toxic than crude leaf aqueous extract in three important vector mosquito species. The results were recorded from UV-Vis spectrum, Fourier transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy analysis (EDX). Considerable mortality was evident after the treatment of C. asiatica for all three important vector mosquitoes. The LC50 and LC90 values of C. asiatica aqueous leaf extract appeared to be effective against An. stephensi (LC50, 90.17 μg/mL; LC90, 165.18 μg/mL) followed by Ae. aegypti (LC50, 96.59 μg/mL; LC90, 173.83 μg/mL) and Cx. quinquefasciatus (LC50, 103.08 μg/mL; LC90, 183.16 μg/mL). Synthesized AgNPs against the vector mosquitoes of An. stephensi, Ae. aegypti, and Cx. quinquefasciatus had the following LC50 and LC90

  4. Metabolic pathways in Anopheles stephensi mitochondria.

    Science.gov (United States)

    Giulivi, Cecilia; Ross-Inta, Catherine; Horton, Ashley A; Luckhart, Shirley

    2008-10-15

    No studies have been performed on the mitochondria of malaria vector mosquitoes. This information would be valuable in understanding mosquito aging and detoxification of insecticides, two parameters that have a significant impact on malaria parasite transmission in endemic regions. In the present study, we report the analyses of respiration and oxidative phosphorylation in mitochondria of cultured cells [ASE (Anopheles stephensi Mos. 43) cell line] from A. stephensi, a major vector of malaria in India, South-East Asia and parts of the Middle East. ASE cell mitochondria share many features in common with mammalian muscle mitochondria, despite the fact that these cells are of larval origin. However, two major differences with mammalian mitochondria were apparent. One, the glycerol-phosphate shuttle plays as major a role in NADH oxidation in ASE cell mitochondria as it does in insect muscle mitochondria. In contrast, mammalian white muscle mitochondria depend primarily on lactate dehydrogenase, whereas red muscle mitochondria depend on the malate-oxaloacetate shuttle. Two, ASE mitochondria were able to oxidize proline at a rate comparable with that of alpha-glycerophosphate. However, the proline pathway appeared to differ from the currently accepted pathway, in that oxoglutarate could be catabolized completely by the tricarboxylic acid cycle or via transamination, depending on the ATP need.

  5. Larvicidal activity and GC-MS analysis of flavonoids of Vitex negundo and Andrographis paniculata against two vector mosquitoes Anopheles stephensi and Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Keerti Gautam

    2013-08-01

    Full Text Available Background & objectives: Development of insect resistance to synthetic pesticides, high operational cost and environmental pollution have created the need for developing alternative approaches to control vector-borne diseases. In the present study, larvicidal activity of flavonoid extracts of different parts of Vitex negundo (Linnaeus and Andrographis paniculata (Nees have been studied against the late III or early IV instar larvae of Aedes aegypti and Anopheles stephensi (Liston. Methods: Flavonoids were extracted from different parts of the selected plants using standard method. Bioassay test was carried out by WHO method for determination of larvicidal activity against mosquitoes. Different compounds of the most active extract were identified by the gas chromatography-mass spectrometry (GC-MS analysis. Results: Flavonoid extract of whole aerial part of A. paniculata was found to be inactive against the selected larvae of Ae. aegypti even at the concentration of 600 ppm, whereas it caused 70% mortality in An. stephensi at the concentration of 200 ppm. Flavonoid extract of flower-buds produced highest mortality (100% at the concentration of 600 ppm for the late III or early IV instar larvae of Ae. aegypti and at the concentration of 200 ppm for the larvae of An. stephensi. GC-MS analysis of the most active flavonoid extract from flower-buds of Vitex showed 81 peaks. Phenol (26.83% area, naphthalene (4.95% area, 2,3-dihydrobenzofuran (6.79% area, Phenol-2,4-Bis (1,1-dimethyl (4.49% area, flavones 4'-OH,5-OH,7-di-O-glucoside (0.25% area and 5-hydroxy- 3,6,7,3',4'-pentamethoxy flavones (0.80% area were present in major amount. Conclusion: Flavonoid extracts from different parts of two selected plants possess larvicidal activity against two selected mosquito species, hence, could be utilized for developing flavonoid-based, ecofriendly insecticide as an alternative to synthetic insecticides.

  6. Chemical composition and larvicidal activity of the essential oil of Plectranthus amboinicus (Lour.) Spreng against Anopheles stephensi: a malarial vector mosquito.

    Science.gov (United States)

    Senthilkumar, Annadurai; Venkatesalu, Venugopalan

    2010-10-01

    Essential oil of Plectranthus amboinicus was studied for its chemical composition and larvicidal potential against the malarial vector mosquito Anopheles stephensi. Totally 26 compounds were identified by GC and GC-MS. The major chemical compounds were carvacrol (28.65%) followed by thymol (21.66%), α-humulene (9.67%), undecanal (8.29%), γ-terpinene (7.76%), ρ-cymene (6.46%), caryophyllene oxide (5.85%), α-terpineol (3.28%) and β-selinene (2.01%). The larvicidal assay was conducted to record the LC(50) and LC(90) values and the larval mortality was observed after 12 and 24 h of exposure period. The LC(50) values of the oil were 33.54 (after 12 h) and 28.37 ppm (after 24 h). The LC(90) values of the oil were 70.27 (after 12 h) and 59.38 ppm (after 24 h). The results of the present study showed that the essential oil of P. amboinicus is one of the inexpensive and eco-friendly sources of natural mosquito larvicidal agent to control/reduce the population of malarial vector mosquito. PMID:20668876

  7. Mosquito larvicidal and pupicidal activity of Euphorbia hirta Linn. (Family:Euphorbiaceae) andBacillus sphaericus against Anopheles stephensiListon. (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    C Panneerselvam; K Murugan; K Kovendan; P Mahesh Kumar; J Subramaniam

    2013-01-01

    Objective:To explore the larvicidal and pupicidal activity ofEuphorbia hirta (E. hirta)leaf extract andBacillus sphaericus (B. sphaericus) against the malarial vector,Anopheles stephensi (An. stephensi).Methods:The larvicidal and pupicidal activity was assayed againstAn. stephensiat various concentrations ranging from (75-375 ppm) under the laboratory as well as field conditions. TheLC50 andLC90value of theE. hirta leaf extract was determined by probit analysis.Results:The plant extract showed larvicidal effects after24 h of exposure; however, the highest larval mortality was found in the methanol extract ofE. hirta against the first to fourth instars larvae and pupae of valuesLC50=137.40,172.65,217.81,269.37 and332.39 ppm;B. sphaericusagainst the first to fourth instars larvae and pupae of valuesLC50=44.29,55.83,68.51,82.19 and95.55 ppm, respectively. Moreover, combined treatment of values ofLC50=79.13,80.42,86.01,93.00 and98.12 ppm, respectively. No mortality was observed in the control.Conclusions:These results suggest methanol leaf extracts ofE. hirta andB. sphaericus have potential to be used as an ideal eco-friendly approach for the control of the malarial vector,An. stephensi as target species of vector control programs. This study provides the first report on the combined mosquito larvicidal and pupicidal activity of this plant crude extract and bacterial toxin againstAn. stephensimosquitoes.

  8. Spectral and HRTEM analyses of Annona muricata leaf extract mediated silver nanoparticles and its Larvicidal efficacy against three mosquito vectors Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti.

    Science.gov (United States)

    Santhosh, Shanthi Bhupathi; Ragavendran, Chinnasamy; Natarajan, Devarajan

    2015-12-01

    Mosquitoes transmit various diseases which mainly affect the human beings and every year cause millions of deaths globally. Currently available chemical and synthetic mosquitocidal agents pose severe side effects, pollute the environment vigorously, and become resistance. There is an urgent need to identify and develop the cost effective, compatible and eco-friendly product for mosquito control. The present study was aimed to find out the larvicidal potential of aqueous crude extract and green synthesized silver nanoparticles (AgNPs) from Annona muricata leaves were tested against fourth instar larvae of three important mosquitoes i.e. Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti using different concentrations of AgNPs (10, 20, 30, 40 and 50 ppm) and the aqueous leaf extract (100, 200, 300, 400, and 500 ppm) for 24 and 48 h. The maximum mortality was noticed in AgNPs than aqueous leaf extract of A. muricata against tested mosquitoes with least LC50 values of 37.70, 31.29, and 20.65 ppm (24h) and 546.7, 516.2, and 618.4 ppm (48 h), respectively. All tested concentrations of AgNps exhibited 100% mortality in A. aegypti larvae at 48 hour observation. In addition, the plant mediated AgNPs were characterized by UV-vis spectrum, Fourier transform infrared spectroscopy, particle size analyser, X-ray diffraction, high resonance transmission electron microscopy, and energy-dispersive X-ray spectroscopy analysis for confirmation of nanoparticle synthesis. Based on the findings of the study suggests that the use of A. muricata plant mediated AgNPs can act as an alternate insecticidal agents for controlling target mosquitoes. PMID:26410042

  9. Spectral and HRTEM analyses of Annona muricata leaf extract mediated silver nanoparticles and its Larvicidal efficacy against three mosquito vectors Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti.

    Science.gov (United States)

    Santhosh, Shanthi Bhupathi; Ragavendran, Chinnasamy; Natarajan, Devarajan

    2015-12-01

    Mosquitoes transmit various diseases which mainly affect the human beings and every year cause millions of deaths globally. Currently available chemical and synthetic mosquitocidal agents pose severe side effects, pollute the environment vigorously, and become resistance. There is an urgent need to identify and develop the cost effective, compatible and eco-friendly product for mosquito control. The present study was aimed to find out the larvicidal potential of aqueous crude extract and green synthesized silver nanoparticles (AgNPs) from Annona muricata leaves were tested against fourth instar larvae of three important mosquitoes i.e. Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti using different concentrations of AgNPs (10, 20, 30, 40 and 50 ppm) and the aqueous leaf extract (100, 200, 300, 400, and 500 ppm) for 24 and 48 h. The maximum mortality was noticed in AgNPs than aqueous leaf extract of A. muricata against tested mosquitoes with least LC50 values of 37.70, 31.29, and 20.65 ppm (24h) and 546.7, 516.2, and 618.4 ppm (48 h), respectively. All tested concentrations of AgNps exhibited 100% mortality in A. aegypti larvae at 48 hour observation. In addition, the plant mediated AgNPs were characterized by UV-vis spectrum, Fourier transform infrared spectroscopy, particle size analyser, X-ray diffraction, high resonance transmission electron microscopy, and energy-dispersive X-ray spectroscopy analysis for confirmation of nanoparticle synthesis. Based on the findings of the study suggests that the use of A. muricata plant mediated AgNPs can act as an alternate insecticidal agents for controlling target mosquitoes.

  10. Larvicidal and pupicidal activity of synthesized silver nanoparticles using Leucas aspera leaf extract against mosquito vectors, Aedes aegypti and Anopheles stephensi

    Directory of Open Access Journals (Sweden)

    S. Sivapriyajothi

    2014-08-01

    Full Text Available Mosquitoes are one of the most medically significant groups of vectors, having an ability to transmit parasites and pathogens that can have devastating impacts on humans. The development of reliable and ecofriendly processes for the synthesis of metallic nanoparticles is an important step in the field of application of nanotechnology. In this study, we address the biosynthesis of silver nanoparticles (AgNPs using Leucas aspera leaf extract, and evaluate its lethal concentration (LC50 and LC90 values against first to fourth instar larvae and pupae of the mosquito vectors, Aedes aegypti and Anopheles stephensi. The nanoparticles were characterized by UV-Vis spectrum, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transformed infrared spectroscopy analysis. Larvae and pupae were exposed to varying concentrations of aqueous extracts of synthesized AgNPs for 24 h. The maximum mortality was observed from synthesized AgNPs, with LC50 values for I-IV instars and pupae ranging from 13.06 to 25.54, and LC90 values ranging from 24.11 to 47.34 for A. aegypti; for A. stephensi, the corresponding LC50 values ranged from 12.45 to 22.26, and the LC90 values ranged from 23.50 to 42.95. With methanol leaf extract of L. aspera against A. aegypti, the LC50 values ranged from 174.89 to 462.96 and the LC90 values ranged from 488.16 to 963.74; for A. stephensi, the corresponding LC50 values ranged from 148.93 to 417.07 and the LC90 values ranged from 449.72 to 912.94. The study suggests that nanoparticles could be a preferred alternative to the most hazardous existing chemical pesticides, contributing to a more healthy environment by providing an ideal ecological and user-friendly vector control strategy for managing malaria and dengue, and contributing to their eventual elimination in the near future.

  11. Mosquito larvicidal activity of some common spices and vegetable waste onCulex quinquefasciatus andAnopheles stephensi

    Institute of Scientific and Technical Information of China (English)

    Someshwar Singha; Goutam Chandra

    2011-01-01

    Objective:To investigate the larvicidal activities of crude and chloroform: methanol (1:1 v/v) extracts of some common spices (Cuminum cyminum, Allium sativum, Zingiber offinale, Curcuma longa) and vegetable waste (Solanum tuberosum germinated tuber) againstAnopheles stephensiandCulex quinquefasciatus mosquito larvae.Methods:Larval mortality of above mosquito species were observed after 24, 48 and72 h of exposure to five concentrations of aqueous extract (0.1%, 0.2%, 0.3%, 0.4% and0.5%) and four concentrations (25, 50, 75 ppm) of chloroform: methanol (1:1 v/v) extract. The lethal concentration of individual spices or vegetable waste was determined by log-probit analysis (at95%confidence level) and effect of crude and chloroform: methanol (1:1 v/v) extracts were recorded on non target organisms.Results:Relative mortality rate of both larval mosquito species were recorded in the following sequences:Cuminum cyminum>Allium sativum>Zingiber offinale, Curcuma longa > Solanum tuberosum germinated tuber for crude extract, and efficacy of chloroform: methanol (1:1 v/v) extract were as follows:Curcuma longa > Zingiber offinale > Solanum tuberosum germinated tuber >Cuminum cyminum>Allium sativum.Conclusions: Crude and chloroform: methanol (1:1 v/v) extract of Cuminum cyminum, Allium sativum, Zingiber offinale, Curcuma longa andSolanum tuberosum germinated tuber can be recommended effectively in mosquito control programmes at very low concentrations. No mortality and other abnormalities were noticed on non target organisms and further studies are needed to investigate the chemical structure of active principal which are responsible for larvicidal activity.

  12. Suppressor of hairy‐wing, modifier of mdg4 and centrosomal protein of 190 gene orthologues of the gypsy insulator complex in the malaria mosquito, Anopheles stephensi

    OpenAIRE

    Carballar‐Lejarazú, R.; Brennock, P; James, A. A.

    2016-01-01

    Abstract DNA insulators organize independent gene regulatory domains and can regulate interactions amongst promoter and enhancer elements. They have the potential to be important in genome enhancing and editing technologies because they can mitigate chromosomal position effects on transgenes. The orthologous genes of the Anopheles stephensi putative gypsy‐like insulator protein complex were identified and expression characteristics studied. These genes encode polypeptides with all the expecte...

  13. The genetics of green thorax, a new larval colour mutant, non-linked with ruby-eye locus in the malaria mosquito, Anopheles stephensi Liston

    OpenAIRE

    Sanil, D.; N. J. Shetty

    2009-01-01

    Background & objectives: Anopheles stephensi, an important vector of malaria continues to be distributed widely in the Indian subcontinent. The natural vigour of the species combined with its new tolerance, indeed resistance to insecticides has made it obligatory that we look for control methods involving genetic manipulation. Hence, there is an immediate need for greater understanding of the genetics of this vector species. One of the requirements for such genetic studies is the establishmen...

  14. Insecticide susceptibility status of Aedes aegypti and Anopheles stephensi larvae against temephos in Delhi, India

    OpenAIRE

    Singh, R. K.; P.K.Mittal; Gaurav Kumar; Dhiman, R.C.

    2014-01-01

    Temephos is used as a larvicide in urban areas in India to control the population of mosquito vectors viz. Anopheles stephensi and Aedes aegypti. The susceptibility status of Ae. aegypti and An. stephensi to temophos in various zones of Municipal Corporation of Delhi was evaluated using the WHO method for determining larval susceptibility test kit. Results revealed that the larval mortality of Ae. aegypti collected from different localities ranged between 64.88% to 98.22%. The highest mortali...

  15. DDT-resistance in Anopheles stephensi.

    Science.gov (United States)

    DAVIDSON, G; JACKSON, C E

    1961-01-01

    In view of the increasing number of reports from different parts of the world indicating resistance to DDT in both adults and larvae of Anopheles stephensi, an important malaria vector, a series of laboratory studies has been carried out on the degree, the pattern and the mode of inheritance of resistance in this species. A DDT-resistant strain from Iraq and a susceptible strain from India were used.In four sets of observations made in the course of tests on both adults and larvae a monofactorial type of inheritance was indicated, and the factor involved was shown to be dependent for its expression on the genetic background.DDT-resistance in A. stephensi appears to be similar in most respects to that in A. sundaicus. PMID:13883789

  16. Stability and Wash Resistance of Local Made Mosquito Bednets and Detergents Treated with Pyrethroids against Anopheles stephensi

    Directory of Open Access Journals (Sweden)

    H Vatandoost

    2009-07-01

    Full Text Available Abstract Background: We aimed to evaluate different fibres of bednets impregnated with various pyrethroids. The stability of insecticide on the bednet was measured using different methods of washings as well as local made detergents."nMethods: The entire test was carried out according to the WHO-recommended methods. In addition, the impact of the numbers of washes on the stability of the insecticides was determined. Permethrin 10% (EC, deltamethrin 10% (SC, lambdacyhalothrin 2.5% (CS and cyfluthrin 5% (EW were used at the recommended dosages. Three different lo­cal detergents were used. Two kinds of washing methods (shaking, no shaking were used and in each method four kinds of washings, i.e. no wash, one wash, two washes and three washes was done. The main malaria vectors, Anophe­les stephensi, which is susceptible to all insecticides (BEECH strain, was tested with impregnated bednets in 3 minutes exposure time and the mortality was measured after 24 hours recovery period. Knock-down was measured as well using appropriate statistical methods."nResults: Lambdacyhalothrin has saved its insecticidal impact after being washed, whereas, deltamethrin has lost its activ­ity faster than other insecticides. Tow other insecticides had moderate effect. Golnar soap detergent has least ef­fect on the durability of insecticides, but the Shoma had the most. Whit increasing  the times of washing, insecticidal ef­fects was decreased , but shaking had no influence on the decreasing  of the quality of insecticidal impact."nConclusion: Results will be useful for local people who wish to use pyrethroid-impregnated bednets with their own lo­cal made detergent and bednets. 

  17. Stability and Wash Resistance of Local Made Mosquito Bednets and Detergents Treated with Pyrethroids against Anopheles stephensi

    Directory of Open Access Journals (Sweden)

    H Vatandoost

    2009-06-01

    Full Text Available Background: We aimed to evaluate different fibres of bednets impregnated with various pyrethroids. The stability of insecticide on the bednet was measured using different methods of washings as well as local made detergents.Methods: The entire test was carried out according to the WHO-recommended methods. In addition, the impact of the numbers of washes on the stability of the insecticides was determined. Permethrin 10% (EC, deltamethrin 10% (SC, lambdacyhalothrin 2.5% (CS and cyfluthrin 5% (EW were used at the recommended dosages. Three different lo­cal detergents were used. Two kinds of washing methods (shaking, no shaking were used and in each method four kinds of washings, i.e. no wash, one wash, two washes and three washes was done. The main malaria vectors, Anophe­les stephensi, which is susceptible to all insecticides (BEECH strain, was tested with impregnated bednets in 3 minutes exposure time and the mortality was measured after 24 hours recovery period. Knock-down was measured as well using appropriate statistical methods.Results: Lambdacyhalothrin has saved its insecticidal impact after being washed, whereas, deltamethrin has lost its activ­ity faster than other insecticides. Tow other insecticides had moderate effect. Golnar soap detergent has least ef­fect on the durability of insecticides, but the Shoma had the most. Whit increasing  the times of washing, insecticidal ef­fects was decreased , but shaking had no influence on the decreasing  of the quality of insecticidal impact.Conclusion: Results will be useful for local people who wish to use pyrethroid-impregnated bednets with their own lo­cal made detergent and bednets. 

  18. Resistance Mechanisms of Anopheles stephensi (Diptera: Culicidae) to Temephos

    OpenAIRE

    Aboozar Soltani; Hassan Vatandoost; MohammadAli Oshaghi; Naseh Maleki-Ravasan; AhmadAli Enayati; Fatemeh Asgarian

    2014-01-01

    Background: Anopheles stephensi is a sub-tropical species and has been considered as one of the most important vector of human malaria throughout the Middle East and South Asian region including the malarious areas of southern Iran. Current reports confirmed An. stephensi resistance to temephos in Oman and India. However, there is no comprehensive research on mechanisms of temephos resistance in An. stephensi in the literature. This study was designed in order to clarify the enzymatic and mol...

  19. Factors affecting fungus-induced larval mortality in Anopheles gambiae and Anopheles stephensi

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    Takken Willem

    2010-01-01

    Full Text Available Abstract Background Entomopathogenic fungi have shown great potential for the control of adult malaria vectors. However, their ability to control aquatic stages of anopheline vectors remains largely unexplored. Therefore, how larval characteristics (Anopheles species, age and larval density, fungus (species and concentration and environmental effects (exposure duration and food availability influence larval mortality caused by fungus, was studied. Methods Laboratory bioassays were performed on the larval stages of Anopheles gambiae and Anopheles stephensi with spores of two fungus species, Metarhizium anisopliae and Beauveria bassiana. For various larval and fungal characteristics and environmental effects the time to death was determined and survival curves established. These curves were compared by Kaplan Meier and Cox regression analyses. Results Beauveria bassiana and Metarhizium anisopliae caused high mortality of An. gambiae and An. stephensi larvae. However, Beauveria bassiana was less effective (Hazard ratio (HR Metarhizium anisopliae. Anopheles stephensi and An. gambiae were equally susceptible to each fungus. Older larvae were less likely to die than young larvae (HR Conclusions This study shows that both fungus species have potential to kill mosquitoes in the larval stage, and that mortality rate depends on fungus species itself, larval stage targeted, larval density and amount of nutrients available to the larvae. Increasing the concentration of fungal spores or reducing the exposure time to spores did not show a proportional increase and decrease in mortality rate, respectively, because the spores clumped together. As a result spores did not provide uniform coverage over space and time. It is, therefore, necessary to develop a formulation that allows the spores to spread over the water surface. Apart from formulation appropriate delivery methods are also necessary to avoid exposing non-target organisms to fungus.

  20. Thermal behaviour of Anopheles stephensi in response to infection with malaria and fungal entomopathogens

    Directory of Open Access Journals (Sweden)

    Read Andrew F

    2009-04-01

    Full Text Available Abstract Background Temperature is a critical determinant of the development of malaria parasites in mosquitoes, and hence the geographic distribution of malaria risk, but little is known about the thermal preferences of Anopheles. A number of other insects modify their thermal behaviour in response to infection. These alterations can be beneficial for the insect or for the infectious agent. Given current interest in developing fungal biopesticides for control of mosquitoes, Anopheles stephensi were examined to test whether mosquitoes showed thermally-mediated behaviour in response to infection with fungal entomopathogens and the rodent malaria, Plasmodium yoelii. Methods Over two experiments, groups of An. stephensi were infected with one of three entomopathogenic fungi, and/or P. yoelii. Infected and uninfected mosquitoes were released on to a thermal gradient (14 – 38°C for "snapshot" assessments of thermal preference during the first five days post-infection. Mosquito survival was monitored for eight days and, where appropriate, oocyst prevalence and intensity was assessed. Results and conclusion Both infected and uninfected An. stephensi showed a non-random distribution on the gradient, indicating some capacity to behaviourally thermoregulate. However, chosen resting temperatures were not altered by any of the infections. There is thus no evidence that thermally-mediated behaviours play a role in determining malaria prevalence or that they will influence the performance of fungal biopesticides against adult Anopheles.

  1. The genetics of green thorax, a new larval colour mutant, non-linked with ruby-eye locus in the malaria mosquito, Anopheles stephensi Liston

    Directory of Open Access Journals (Sweden)

    D. Sanil

    2009-06-01

    Full Text Available Background & objectives: Anopheles stephensi, an important vector of malaria continues to be distributed widely in the Indian subcontinent. The natural vigour of the species combined with its new tolerance, indeed resistance to insecticides has made it obligatory that we look for control methods involving genetic manipulation. Hence, there is an immediate need for greater understanding of the genetics of this vector species. One of the requirements for such genetic studies is the establishment of naturally occurring mutants, establishment of the genetic basis for the same and use of such mutants in the genetic transformation studies and other genetic control programme(s. This paper describes the isolation and genetic studies of a larval colour mutant, green thorax (gt, and linkage studies involving another autosomal recessive mutant ruby-eye (ru in An. stephensi. Methods: After the initial discovery, the mutant green thorax was crossed inter se and pure homozygous stock of the mutant was established. The stock of the mutant ruby-eye, which has been maintained as a pure stock in the laboratory. Crosses were made between the wild type and mutant, green thorax to determine the mode of inheritance of green thorax. For linkage studies, crosses were made between the mutant green thorax and another autosomal recessive mutant ruby-eye. The percentage cross-over was calculated for the genes linkage relationship for gt and gt ru. Results: Results of crosses between mutant and wild type showed that the inheritance of green thorax (gt in An. stephensi is monofactorial in nature. The gt allele is recessive to wild type and is autosomal. The linkage studies showed no linkage between ru and gt. Interpretation & conclusion: The mutant gt represents an excellent marker for An. stephensi as it is expressed in late III instar stage of larvae and is prominent in IV instar and pupal stages with complete penetrance and high viability. The said mutant could be easily

  2. Robust and regulatory expression of defensin A gene driven by vitellogenin promoter in transgenic Anopheles stephensi

    Institute of Scientific and Technical Information of China (English)

    CHEN XiaoGuang; ZHANG YaJing; ZHENG XueLi; WANG ChunMei

    2007-01-01

    The use of genetically modified mosquitoes to reduce or replace field populations is a new strategy to control mosquito-borne diseases. The precondition of the implementation of this strategy is the ability to manipulate the genome of mosquitoes and to induce specific expression of the effector molecules driven by a suitable promoter. The objective of this study is to evaluate the expression of defensin A gene of Anopheles sinensis under the control of a vitellogenin promoter in transgenic Anopheles stephensi. The regulatory region of Anopheles gambiae vitellogenin was cloned and subcloned into transfer vector pSLFa consisting of an expression cassette with defensin A coding sequence. Then, the expression cassette was transferred into transformation vector pBac[3xP3-DsRedafm] using Asc I digestion. The recombinant plasmid DNA of pBac[3xP3DsRed-AgVgT2-DefA] and helper plasmid DNA of phsp-pBac were micro-injected into embryos of An. stephensi. The positive transgenic mosquitoes were screened by observing specific red fluorescence in the eyes of G1 larvae. Southern blot analysis showed that a single-copy transgene integrated into the genome of An. stephensi. RT-PCR analysis showed that the defensin A gene expressed specifically in fat bodies of female mosquitoes after a blood meal. Interestingly, the mRNA of defensin A is more stable compared with that of the endogenous vitellogenin gene. After multiple blood meals, the expression of defensin A appeared as a reducible and non-cycling type, a crucial feature for its anti-pathogen effect. From data above, we concluded that the regulatory function of the Vg promoter and the expression of defensin A gene were relatively conserved in different species of anopheles mosquitoes. These molecules could be used as candidates in the development of genetically modified mosquitoes.

  3. Imidacloprid and Thiamethoxam Induced Mutations in Internal Transcribed Spacer 2 (ITS2) of Anopheles stephensi

    OpenAIRE

    Bhinder, Preety; Chaudhry, Asha; Barna, Bhupinder; Kaur, Satvinderjeet

    2012-01-01

    The present article deals with the polymerase chain reaction (PCR)-based genotoxicity evaluation of neonicotinoid pesticides, imidacloprid and thiamethoxam, by using the genome of a mosquito Anopheles stephensi taken as an experimental model. After treatment of the second instar larvae with LC20 of the pesticides for 24 h, the induced nucleotide sequence variations in the internal transcribed spacer 2 (ITS2) of freshly hatched unfed control and treated individuals was studied from the sequenc...

  4. Mosquitocidal activity of Polygala arvensis Willd against Aedes aegypti (Linn., Anopheles stephensi (Liston. and Culex quinquefasciatus (Say. (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    M. Deepa

    2014-12-01

    Full Text Available To determine the larvicidal, ovicidal and repellent activities of benzene and methanol extract of Polygala arvensis against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus Twenty five 3rd instar larvae of selected mosquitoes species were exposed to various concentrations (60-300 ppm and were assayed in the laboratory by using the protocol of WHO 2005; the 24 h LC50 values of the P. Arvensis leaf extract was determined following Probit analysis. The ovicidal activity was determined against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus exposed to variousconcentrations were tested under laboratory conditions and the hatch rates were assessed 120hrs post treatment. The repellent efficacy was determined against selected mosquitoes at three concentrations viz., 1.0, 2.0 and 3.0 mg/cm2 under the laboratory conditions. The LC50 and LC90 values of benzene and methanol extract of P. arvensis against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus larvae in 24 h were 75.32, 88.26, 82.46, 58.21, 46.37, 42.68 and 260.48, 275.26, 251.39, 208.45, 189.82 and 130.44 ppm, respectively. It has been noticed that the higher concentrations of P. arvensis extractspossesses strong ovicidal activity at 200 ppm concentration against Ae. aegypti, An. stephensi and C. quinquefasciatus, no egg hatchability was recorded. In the same way, methanol extracts showed maximum ovicidal activity followed by benzene extract against selected vector mosquitoes. In repellent activity, among two extracts tested P. arvensis methanol extract had strong repellent action against selected mosquitoes as it provided 100% protection against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus for 280min. From the results it can be concluded the P. arvensis extract was an excellent potential for controlling Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus mosquitoes.

  5. Transcriptome analysis of Anopheles stephensi embryo using expressed sequence tags

    Indian Academy of Sciences (India)

    Kaustubh Gokhale; Deepak P Patil; Dhiraj P Dhotre; Rajnikant Dixit; Murlidhar J Mendki; Milind S Patole; Yogesh S Shouche

    2013-06-01

    Germ band retraction (GBR) stage is one of the important stages during insect development. It is associated with an extensive epithelial morphogenesis and may also be pivotal in generation of morphological diversity in insects. Despite its importance, only a handful of studies report the transcriptome repertoire of this stage in insects. Here, we report generation, annotation and analysis of ESTs from the embryonic stage (16–22 h post fertilization) of laboratory-reared Anopheles stephensi mosquitoes. A total of 1002 contigs were obtained upon clustering of 1140 high-quality ESTs, which demonstrates an astonishingly low transcript redundancy (12.1%). Putative functions were assigned only to 213 contigs (21%), comprising mainly of transcripts encoding protein synthesis machinery. Approximately 78% of the transcripts remain uncharacterized, illustrating a lack of sequence information about the genes expressed in the embryonic stages of mosquitoes. This study highlights several novel transcripts, which apart from insect development, may significantly contribute to the essential biological complexity underlying insect viability in adverse environments. Nonetheless, the generated sequence information from this work provides a comprehensive resource for genome annotation, microarray development, phylogenetic analysis and other molecular biology applications in entomology.

  6. "Comparison of Midgut Hemagglutination Activity in Three Different Geographical Populations of Anopheles stephensi"

    Directory of Open Access Journals (Sweden)

    HR Basseri

    2004-08-01

    Full Text Available Lectins that agglutinate red blood cells (RBCs were demonstrated in Anopheles stephensi mosquito midgut extracts using human (four groups: A, B, AB and O, RH+ rat, sheep and rabbit blood cells. Only rabbit RBCs showed agglutination reaction against the midgut extracts. Significant differences in hemagglutinin titers and carbohydrate specifity were detected between male and female mosquitoes as well as among three different geographical populations of Anopheles stephensi from south of Iran. Overall agglutinin levels were increased following a blood meal. The highest hemagglintination titers were due to Kazerun population. All hemagglutination assays were versus rabbit RBCS. A significant difference was detected among the number of egg-float ridges. Iranshahr population was different from Bandar-abbas and Kazerun population in egg-float ridges number. Bandr-abbas population was in the intermediate category. Iranshahr population fell between mysoransis and intermediate group and Kazerun population was between intermediate and type form. This study presents the first report on the occurrence of heterogeneous anti Rabbit RBC agglutinins in the midget extracts of the different geographical populations of An.stephensi with the sugar – binding specificities. The sugar- inhibition pattern was different between & within geographical population of An.stephensi.

  7. Resistance Mechanisms of Anopheles stephensi (Diptera: Culicidae to Temephos

    Directory of Open Access Journals (Sweden)

    Aboozar Soltani

    2015-10-01

    Full Text Available Background: Anopheles stephensi is a sub-tropical species and has been considered as one of the most important vector of human malaria throughout the Middle East and South Asian region including the malarious areas of southern Iran. Current reports confirmed An. stephensi resistance to temephos in Oman and India. However, there is no comprehensive research on mechanisms of temephos resistance in An. stephensi in the literature. This study was designed in order to clarify the enzymatic and molecular mechanisms of temephos resistance in this species.Methods: Profile activities of α- and ß-esterases, mixed function oxidase (MFO, glutathione-S-transferase (GST, insensitive acetylcholinesterase, and para-nitrophenyl acetate (PNPA-esterase enzymes were tested for An. stephensi strain with resistance ratio of 15.82 to temephos in comparison with susceptible strain.Results: Results showed that the mean activity of α-EST, GST and AChE enzymes were classified as altered indicating metabolic mechanisms have considerable role in resistance of An. stephensi to temephos. Molecular study using PCR-RFLP method to trace the G119S mutation in ACE-1 gene showed lack of the mutation responsible for organophosphate insecticide resistance in the temephos-selected strain of An. stephensi.Conclusion: This study showed that the altered enzymes but not targets site insensitivity of ACE-1 are responsible for temephos resistance in An. stephensi in south of Iran.

  8. Mass Spectrometry Based Proteomic Analysis of Salivary Glands of Urban Malaria Vector Anopheles stephensi

    Directory of Open Access Journals (Sweden)

    Sonam Vijay

    2014-01-01

    Full Text Available Salivary gland proteins of Anopheles mosquitoes offer attractive targets to understand interactions with sporozoites, blood feeding behavior, homeostasis, and immunological evaluation of malaria vectors and parasite interactions. To date limited studies have been carried out to elucidate salivary proteins of An. stephensi salivary glands. The aim of the present study was to provide detailed analytical attributives of functional salivary gland proteins of urban malaria vector An. stephensi. A proteomic approach combining one-dimensional electrophoresis (1DE, ion trap liquid chromatography mass spectrometry (LC/MS/MS, and computational bioinformatic analysis was adopted to provide the first direct insight into identification and functional characterization of known salivary proteins and novel salivary proteins of An. stephensi. Computational studies by online servers, namely, MASCOT and OMSSA algorithms, identified a total of 36 known salivary proteins and 123 novel proteins analysed by LC/MS/MS. This first report describes a baseline proteomic catalogue of 159 salivary proteins belonging to various categories of signal transduction, regulation of blood coagulation cascade, and various immune and energy pathways of An. stephensi sialotranscriptome by mass spectrometry. Our results may serve as basis to provide a putative functional role of proteins in concept of blood feeding, biting behavior, and other aspects of vector-parasite host interactions for parasite development in anopheline mosquitoes.

  9. Ovicidal and repellent activities of botanical extracts against Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Govindarajan M; Mathivanan T; Elumalai K; Krishnappa K; Anandan A

    2011-01-01

    Objective: To determine the ovicidal and repellent activities of methanol leaf extract ofErvatamia coronaria (E. coronaria) and Caesalpinia pulcherrima (C. pulcherrima) against Culex quinquefasciatus (Cx. quinquefasciatus), Aedes aegypti (Ae. aegypti) and Anopheles stephensi (An. stephensi). Methods: The ovicidal activity was determined against three mosquito species at various concentrations ranging from 50-450 ppm under the laboratory conditions. The hatch rates were assessed 48 h after treatment. The repellent efficacy was determined against three mosquito species at three concentrations viz., 1.0, 2.5 and 5.0 mg/cm2 under the laboratory conditions.Results:The crude extract of E. coronaria exerted zero hatchability (100% mortality) at 250, 200 and 150 ppm for Cx. quinquefasciatus, Ae. aegypti and An. stephensi, respectively. The crude extract of C. pulcherrima exerted zero hatchability (100% mortality) at 375, 300 and 225 ppm for Cx. quinquefasciatus, Ae. aegypti and An. Stephensi, respectively. The methanol extract of E. coronaria found to be more repellenct than C. pulcherrima extract. A higher concentration of 5.0 mg/cm2 provided 100% protection up to 150, 180 and 210 min against Cx. quinquefasciatus, Ae.aegypti and An. stephensi, respectively. The results clearly showed that repellent activity was dose dependent. Conclusions: From the results it can be concluded the crude extracts of E. coronaria and C. pulcherrima are an excellent potential for controlling Cx. quinquefasciatus, Ae. aegypti and An. stephensi mosquitoes.

  10. Larvicidal and pupicidal activity of spinosad against the malarial vector Anopheles stephensi

    Institute of Scientific and Technical Information of China (English)

    Kolanthasamy Prabhu; Kadarkarai Murugan; Arjunan Nareshkumar; Subramanian Bragadeeswaran

    2011-01-01

    Objective:To investigate the larvicidal and pupicidal activity of spinosad againstAnopheles stephensi Listen.Methods: Spinosad from the actinomycete,Saccharopolyspora spinosa was tested againstAnopheles stephensi at different concentrations (0.01, 0.02, 0.04, 0.06 and0.08ppm.), and against first to fourth instar larvae and pupae.Results: The larval mortality ranged from36.1±1.7 in (0.01 ppm) to 79.3±1.8 (0.08 ppm) the first instar larva. The LC50andLC90values of first, second, third and fourth instar larva were0.001, 0.031, 0.034, 0.036and0.0113, 0.102, 0.111, 0.113, respectively. The pupal mortality ranged from33.0±2.0 (0.01 ppm) to 80.0±0.9 (0.08 ppm). The LC50 andLC90values were0.028 and 0.1020, respectively. The reduction percentage ofAnopheles larvae was82.7%, 91.4% and96.0% after 24, 48, 72 hours, respectively, while more than80% reduction was observed after3 weeks.Conclusions:In the present study spinosad effectively caused mortality of mosquito larvae in both the laboratory and field trial. It is predicted that spinosad is likely to be an effective larvicide for treatment of mosquito breeding sites.

  11. Larvicidal activity of oak Quercus infectoria Oliv. (Fagaceae) gall extracts against Anopheles stephensi Liston.

    Science.gov (United States)

    Aivazi, Ali-Ashraf; Vijayan, V A

    2009-06-01

    There is a growing interest in the use of botanical insecticides to reduce the use of synthetic pesticides in order to avoid environmental side effects. Anopheles stephensi is the primary vector of urban malaria, an endemic disease in India. So, an effort to assay An. stephensi larvae with gall extracts of Quercus infectoria was made under laboratory conditions at Mysore. Ethyl-acetate extract was found to be the most effective of all the five extracts tested for larvicidal activity against the fourth instar larvae, with LC(50) of 116.92 ppm followed by gallotannin, n-butanol, acetone, and methanol with LC(50) values of 124.62, 174.76, 299.26, and 364.61 ppm, respectively. The efficacy in killing mosquito larvae may make this plant promising for the development of new botanical larvicide. PMID:19148681

  12. Larvicidal activity of oak Quercus infectoria Oliv. (Fagaceae) gall extracts against Anopheles stephensi Liston.

    Science.gov (United States)

    Aivazi, Ali-Ashraf; Vijayan, V A

    2009-06-01

    There is a growing interest in the use of botanical insecticides to reduce the use of synthetic pesticides in order to avoid environmental side effects. Anopheles stephensi is the primary vector of urban malaria, an endemic disease in India. So, an effort to assay An. stephensi larvae with gall extracts of Quercus infectoria was made under laboratory conditions at Mysore. Ethyl-acetate extract was found to be the most effective of all the five extracts tested for larvicidal activity against the fourth instar larvae, with LC(50) of 116.92 ppm followed by gallotannin, n-butanol, acetone, and methanol with LC(50) values of 124.62, 174.76, 299.26, and 364.61 ppm, respectively. The efficacy in killing mosquito larvae may make this plant promising for the development of new botanical larvicide.

  13. Insecticidal, repellent and oviposition-deterrent activity of selected essential oils against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus.

    Science.gov (United States)

    Prajapati, Veena; Tripathi, A K; Aggarwal, K K; Khanuja, S P S

    2005-11-01

    Essential oils extracted from 10 medicinal plants were evaluated for larvicidal, adulticidal, ovicidal, oviposition-deterrent and repellent activities towards three mosquito species; Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus. The essential oils of Juniperus macropoda and Pimpinella anisum were highly effective as both larvicidal and ovicidal. The essential oil of P. anisum showed toxicity against 4th instar larvae of A. stephensi and A. aegypti with equivalent LD95 values of 115.7 microg/ml, whereas it was 149.7 microg/ml against C. quinquefasciatus larvae. Essential oils of Zingiber officinale and Rosmarinus officinalis were found to be ovicidal and repellent, respectively towards the three mosquito species. The essential oil of Cinnamomum zeylanicum resulted into highest repellent (RD95) values of 49.6, 53.9 and 44.2 mg/mat against A. stephensi, A. aegypti and C. quinquefasciatus, respectively apart from oviposition-deterrent potential. PMID:16051081

  14. Larvicidal potential of essential oils against Musca domestica and Anopheles stephensi.

    Science.gov (United States)

    Chauhan, Nitin; Malik, Anushree; Sharma, Satyawati; Dhiman, R C

    2016-06-01

    The larvicidal activity of Mentha piperita, Cymbopogan citratus (lemongrass), Eucalyptus globulus and Citrus sinensis (orange) essential oils and their combinations was evaluated against Musca domestica (housefly) and Anopheles stephensi (mosquitoes) through contact toxicity assay. Among all the tested essential oils/combinations, Me. piperita was found to be the most effective larvicidal agent against Mu. domestica and An. stephensi with LC50 values of 0.66 μl/cm(2) and 44.66 ppm, respectively, after 48 h. The results clearly highlighted that the addition of mentha oil to other oils (1:1 ratio) improved their larvicidal activity. The order of effectiveness of essential oils/combinations indicated that the pattern for An. stephensi follows the trend as mentha > mentha + lemongrass > lemongrass > mentha + eucalyptus > eucalyptus > mentha + orange > orange and for Mu. domestica as mentha > mentha + lemongrass > lemongrass > mentha + orange > orange > mentha + eucalyptus > eucalyptus. The images obtained from scanning electron microscopy (SEM) analysis indicated the toxic effect of Me. piperita as the treated larvae were observed to be dehydrated and deformed. This study demonstrates the effectiveness of tested essential oils/combinations against the larval stages of Mu. domestica and An. stephensi and has the potential for development of botanical formulations.

  15. Molecular characterization, biological forms and sporozoite rate of Anopheles stephensi in southern Iran

    Institute of Scientific and Technical Information of China (English)

    Ali Reza Chavshin; Mohammad Ali Oshaghi; Hasan Vatandoost; Ahmad Ali Hanafi-Bojd; Ahmad Raeisi; Fatemeh Nikpoor

    2014-01-01

    Objective: To identify the biological forms, sporozoite rate and molecular characterization of the Anopheles stephensi (An. stephensi) in Hormozgan and Sistan-Baluchistan provinces, the most important malarious areas in Iran. Methods: Wild live An. stephensi samples were collected from different malarious areas in southern Iran. The biological forms were identified based on number of egg-ridges. Molecular characterization of biological forms was verified by analysis of the mitochondrial cytochrome oxidase subunit I and II (mtDNA-COI/COII). The Plasmodium infection was examined in the wild female specimens by species-specific nested–PCR method. Results: Results showed that all three biological forms including mysorensis, intermediate and type are present in the study areas. Molecular investigations revealed no genetic variation between mtDNA COI/COII sequences of the biological forms and no Plasmodium parasites was detected in the collected mosquito samples. Conclusions:Presence of three biological forms with identical sequences showed that the known biological forms belong to a single taxon and the various vectorial capacities reported for these forms are more likely corresponded to other epidemiological factors than to the morphotype of the populations. Lack of malaria parasite infection in An. stephensi, the most important vector of malaria, may be partly due to the success and achievement of ongoing active malaria control program in the region.

  16. Larvicidal potential of essential oils against Musca domestica and Anopheles stephensi.

    Science.gov (United States)

    Chauhan, Nitin; Malik, Anushree; Sharma, Satyawati; Dhiman, R C

    2016-06-01

    The larvicidal activity of Mentha piperita, Cymbopogan citratus (lemongrass), Eucalyptus globulus and Citrus sinensis (orange) essential oils and their combinations was evaluated against Musca domestica (housefly) and Anopheles stephensi (mosquitoes) through contact toxicity assay. Among all the tested essential oils/combinations, Me. piperita was found to be the most effective larvicidal agent against Mu. domestica and An. stephensi with LC50 values of 0.66 μl/cm(2) and 44.66 ppm, respectively, after 48 h. The results clearly highlighted that the addition of mentha oil to other oils (1:1 ratio) improved their larvicidal activity. The order of effectiveness of essential oils/combinations indicated that the pattern for An. stephensi follows the trend as mentha > mentha + lemongrass > lemongrass > mentha + eucalyptus > eucalyptus > mentha + orange > orange and for Mu. domestica as mentha > mentha + lemongrass > lemongrass > mentha + orange > orange > mentha + eucalyptus > eucalyptus. The images obtained from scanning electron microscopy (SEM) analysis indicated the toxic effect of Me. piperita as the treated larvae were observed to be dehydrated and deformed. This study demonstrates the effectiveness of tested essential oils/combinations against the larval stages of Mu. domestica and An. stephensi and has the potential for development of botanical formulations. PMID:26920567

  17. Baseline Susceptibility of Different Geographical Strains of Anopheles stephensi (Diptera: Culicidae) to Temephos in Malarious Areas of Iran

    OpenAIRE

    Aboozar Soltani; Hassan Vatandoost; Mohammad Ali Oshaghi; Ahmad Ali Enayati; Ahmad Raeisi; Mohammad Reza Eshraghian; Mohammad Mehdi Soltan-Dallal; Ahmad Ali Hanafi-Bojd; Mohammad Reza Abai; Fatemeh Rafi

    2013-01-01

    Background: Malaria still remains a public health problem in Iran. There are different vector control interventions such as insecticide spraying. The present study was carried out to determine the susceptibility status of Anopheles stephensi larvae to temephos as a national plan for monitoring and mapping of insecticide resistance Methods: Eight different localities in two main malarious provinces were determined as field collecting sites. Mosquitoes were collected from the field and reared i...

  18. Studies on the effects of sida acuta and vetiveria zizanioides against the malarial vector, anopheles stephensi and malarial parasite, plasmodium berghei

    Science.gov (United States)

    Methanolic extracts of Sida acuta and Vetiveria zizanioides leaves and root were studied for toxicity to Anopheles stephensi mosquitoes and to the malaria parasite Plasmodium berghei in mice. The extracts reduced parasitemia levels in mice by 17-69%, depending on extract concentration. Median le...

  19. "Behaviour changes in Permethrin-resistant strain of Anopheles Stephensi "

    Directory of Open Access Journals (Sweden)

    Vatandoost H

    2000-09-01

    Full Text Available Behaviour studies indicated that the permethrin resistant strin of An. Stephensi was 3-fold resistant to knock-down compared with the susceptible strain. The resistant strain was however 3-fold less irritable to permethrin and less responsive than the susceptible strain to the movement of an aspirator. If reduced irritability and reduced responsiveness to catch are consequences of the changes in the nervous system, then such a form of resistance may be disadvantageous to mosquitoes in natural populations.

  20. Effect of Chloroxylon swietenia Dc bark extracts against Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi larvae.

    Science.gov (United States)

    Balasubramanian, Jayaprasad; Subramanian, Sharavanan; Kaliyan, Veerakumar

    2015-11-01

    Mosquitoes are the vector of more diseases and cause major health problems like malaria, dengue, chikungunya, and lymphatic filariasis. This article deals with the mosquito larvicidal activity of Chloroxylon swietenia Dc bark extracts against late third instar larvae of Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi. Methanolic crude extract of Ch. swietenia bark was obtained by soxhlet apparatus and aqueous crude extract by cold percolation method. The range of concentrations of the crude extracts used was 50, 100, 150, 200, and 250 ppm. The mortality and lethal concentration (LC50 and LC90) was calculated after a 24-h exposure period. Both the extracts showed trustworthy larvicidal activity. The larvicidal activity of the methanol extract of Ch. swietenia bark was higher than the aqueous extract, and the LC50 and the LC90 values of the methanol extract were found to be 124.70 and 226.26 μg/ml (Ae. aegypti), 130.57 and 234.67 ppm (Cu. quinquefasciatus), and 137.55 and 246.09 ppm (An. stephensi). The LC50 and the LC90 values of the aqueous extract were found to be 133.10 and 238.93 ppm (Ae. aegypti), 136.45 and 242.47 ppm (Cu. quinquefasciatus), and 139.43 and 248.64 ppm (An. stephensi). No mortality was observed in the control. Methanolic crude extract Ch. swietenia bark shows higher activity against An. stephensi than the other two tested larvae and aqueous extract. The results of the present study propose a possible way for further investigations to find out the active molecule responsible for the larvicidal activity of Ch. swietenia bark extracts. PMID:26246308

  1. Oviposition deterrent and skin repellent activities of Solanum trilobatum leaf extract against the malarial vector Anopheles stephensi.

    OpenAIRE

    Rajkumar, S.; Jebanesan, A.

    2005-01-01

    The leaf extract of Solanum trilobatum (Solanaceae) was tested under laboratory conditions for oviposition deterrent and skin repellent activities against the adult mosquito Anopheles stephensi. Concentrations of 0.01, 0.025, 0.05, 0.075 and 0.1% reduced egg laying by gravid females from 18 to 99% compared to ethanol-treated controls. In skin repellent tests, concentrations of 0.001, 0.005, 0.01, 0.015, and 0.02 % provided 70 to 120 minutes protection against mosquito bites, whereas the ethan...

  2. Insecticide susceptibility status of Aedes aegypti and Anopheles stephensi larvae against temephos in Delhi, India

    Directory of Open Access Journals (Sweden)

    R.K. Singh

    2014-09-01

    Full Text Available Temephos is used as a larvicide in urban areas in India to control the population of mosquito vectors viz. Anopheles stephensi and Aedes aegypti. The susceptibility status of Ae. aegypti and An. stephensi to temophos in various zones of Municipal Corporation of Delhi was evaluated using the WHO method for determining larval susceptibility test kit. Results revealed that the larval mortality of Ae. aegypti collected from different localities ranged between 64.88% to 98.22%. The highest mortality was recorded from Sangam Vihar (98.22% and lowest was recorded from Majnu ka tila (64.88%. Ae. aegypti larvae collected from Sangam Vihar locality was found fully susceptible to temephos, from two localities viz. Uttam Nagar and Pitampura of study area were tolerant to temephos, and from five localities viz. Majnu ka tila, Shastri Park, Mayur Vihar II, Tilak Bridge and Nagal Dewat showed development of resistance against temephos at diagnostic concentrations. However, larval populations of An. stephensi were fully susceptible to temephos in all the localities. The present study indicates the possible development of resistance against temephos in the larvae of Ae. aegypti in some areas in Delhi.

  3. Pteridine fluorescence for age determination of Anopheles mosquitoes.

    Science.gov (United States)

    Wu, D; Lehane, M J

    1999-02-01

    The age structure of mosquito populations is of great relevance to understanding the dynamics of disease transmission and in monitoring the success of control operations. Unfortunately, the ovarian dissection methods currently available for determining the age of adult mosquitoes are technically difficult, slow and may be of limited value, because the proportion of diagnostic ovarioles in the ovary declines with age. By means of reversed-phase HPLC this study investigated the malaria vectors Anopheles gambiae and An. stephensi to see if changes in fluorescent pteridine pigments, which have been used in other insects to determine the age of field-caught individuals, may be useful for age determination in mosquitoes. Whole body fluorescence was inversely proportional to age (P 91%) up to 30 days postemergence, with the regression values: y = 40580-706x for An. gambiae, and y = 52896-681x for An. stephensi. In both species the main pteridines were 6-biopterin, pterin-6-carboxylic acid and an unidentified fluorescent compound. An. gambiae had only 50-70% as much fluorescence as An. stephensi, and fluorescent compounds were relatively more concentrated in the head than in the thorax (ratios 1:0.8 An. gambiae; 1:0.5 An. stephensi). The results of this laboratory study are encouraging. It seems feasible that this simpler and faster technique of fluorescence quantification could yield results of equivalent accuracy to the interpretation of ovarian dissection. A double-blind field trial comparing the accuracy of this technique to marked, released and recaptured mosquitoes is required to test the usefulness of the pteridine method in the field. PMID:10194749

  4. Ovicidal and repellent activities of botanical extracts against Culex quinquefasciatus,Aedes aegypti and Anopheles stephensi(Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Govindarajan; M; Mathivanan; T; Elumalai; K; Krishnappa; K; Anandan; A

    2011-01-01

    Objective:To determine the ovicidal and repellent activities of methanol leaf extract of Ervatamia coronaria(E.coronaria) and Caeslpinia pulckerrima(C.pulcherrima) against Culex quinquefasciatus(Cx.quinquefasciatus),Aedes aegypti(Ae.aegypti) and Anopheles stephensi(An. stephensi).Methods:The ovicidal activity was determined against three mosquito species at various concentrations ranging from 50-450 ppm under the laboratory conditions.The hatch rates were assessed 48 h after treatment.The repellent efficacy was determined against three mosquito species at three concentrations viz.,1.0,2.5 and 5.0 mg/cm under the laboratory conditions. Results:The crude extract of E.coronaria exerted zero hatchability(100%mortality) at 250.200 and 150 ppm for Cx.quinqitefasciatus,Ae.aegypti and An.stephensi,respectively.The crude extract of C.pulchenima exerted zero hatchability(100%mortality) at 375.300 and 225 ppm for Cx.quinquefasciatus,Ae.aegypti and An.Stephensi,respectively.The methanol extract of E. coronaria found to be more repellenct than C.pukherrima extract.A higher concentration of 5.0 mg/cm~2 provided 100%protection up to 150.180 and 210 min against Cx.quinquefasciatus,Ae. aegypti and An.stephensi,respectively.The results clearly showed that repellent activity was dose dependent.Conclusions:From the results it can be concluded the crude extracts of E.coronaria and C.pukherrima are an excellent potential for controlling Cx.quinquefasciatus,Ae.aegypti and An.stephensi mosquitoes.

  5. Electroantennogram, flight orientation and oviposition responses of Anopheles stephensi and Aedes aegypti to a fatty acid ester-propyl octadecanoate.

    Science.gov (United States)

    Seenivasagan, Thangaraj; Sharma, Kavita R; Prakash, Shri

    2012-10-01

    Studies were carried out to evaluate the role of a C(21)-fatty acid ester; propyl octadecanoate (PO) for olfaction-mediated behavioral responses of urban malaria vector, Anopheles stephensi and dengue vector, Aedes aegypti mosquitoes using electroantennogram (EAG), flight orientation and oviposition experiments. Dose dependent electrophysiological responses were recorded for PO from the antenna of both mosquito species in which 10(-5) g elicited significant EAG response. An. stephensi exhibited 2.4, 4.2 and 5.5 fold increased EAG response compared to control, while Ae. aegypti showed 1.9, 4.6 and 5.8 fold EAG responses respectively at 10(-7) g, 10(-6) g and 10(-5) g doses. In the Y-tube olfactometer, 77-80% gravid females of An. stephensi, and 64-77% of Ae. aegypti were caught in the chambers releasing 10(-6) g and 10(-5) g plume of PO. The synthetic fatty acid ester loaded onto an effervescent tablet at 0.1 mg/L, 1 mg/L and 10 mg/L elicited increased ovipositional responses from gravid mosquitoes compared to control. The oviposition activity indices (OAI) of An. stephensi females were +0.40, +0.51 and +0.58, whereas the OAI for Ae. aegypti females were +0.05, +0.36 and +0.57 respectively in 0.1, 1, 10 mg/L of PO; indicated concentration dependent increased egg deposition. Similarly, in the residual activity studies, oviposition substrates treated with PO on effervescent tablet at 1mg/L and 10mg/L received significantly increased egg deposition by gravid females of both mosquito species for up to 1 week compared to control substrates. PO can potentially be used in ovitraps to monitor An. stephensi and Ae. aegypti populations in the vector surveillance programs.

  6. Insecticidal activity of the essential oil of Thymus transcaspicus against Anopheles stephensi

    Institute of Scientific and Technical Information of China (English)

    Leila Dargahi; Kamal Razavi-Azarkhiavi; Mohammad Ramezani; Mohammad Reza Abaee; Javad Behravan

    2014-01-01

    Objective:To investigate the insecticidal activity of the essential oil of Thymus transcaspicus (T. transcaspicus) against Anopheles stephensi (An. stephensi). Methods:An. stephensi were exposed to 31, 63, 125 and 250 µg/L of essential oil of T. transcaspicus for 24 h. Results:The most toxicity was observed at 250 µg/L of essential oil with the LC50 values of 134.1 µg/L after 24 h. Conclusions:The essential oil of T. transcaspicus exhibited strong insecticidal activity against An. stephensi which can be attributed to its constituent especially carvacrol and thymol phenols.

  7. Laser induced mortality of Anopheles stephensi mosquitoes

    Science.gov (United States)

    Keller, Matthew D.; Leahy, David J.; Norton, Bryan J.; Johanson, Threeric; Mullen, Emma R.; Marvit, Maclen; Makagon, Arty

    2016-02-01

    Small, flying insects continue to pose great risks to both human health and agricultural production throughout the world, so there remains a compelling need to develop new vector and pest control approaches. Here, we examined the use of short (insects in the wild.

  8. Laser induced mortality of Anopheles stephensi mosquitoes.

    Science.gov (United States)

    Keller, Matthew D; Leahy, David J; Norton, Bryan J; Johanson, Threeric; Mullen, Emma R; Marvit, Maclen; Makagon, Arty

    2016-01-01

    Small, flying insects continue to pose great risks to both human health and agricultural production throughout the world, so there remains a compelling need to develop new vector and pest control approaches. Here, we examined the use of short (orders of magnitude to significantly lower the lethal pulse energy or fluence required. These results identified the most promising candidates for the lethal laser component in a system being designed to identify, track, and shoot down flying insects in the wild. PMID:26887786

  9. Partial genomic organization of ribosomal protein S7 gene from malaria vector Anopheles stephensi

    Institute of Scientific and Technical Information of China (English)

    RAJNIKANT DIXIT; SARITA DIXIT; UPAL ROY; YOGESH S.SHOUCHE; SURENDRA GAKHAR

    2007-01-01

    In this study, we describe the partial genomic organization of ribosomal protein S7 gene isolated from the mosquito Anopheles stephensi. Initially a 558 bp partial cDNA sequence was amplified as precursor mRNA sequence containing 223 bp long intron. 5' and 3' end sequences were recovered using end specific rapid amplification of cDNA ends (RACE) polymerase chain reaction. The full-length cDNA sequence was 914 nucleotide long with an open reading frame capable of encoding 192 amino acid long protein with calculated molecular mass of 22174 Da and a pI point of 9.94. Protein homology search revealed >75% identity to other insect's S7 ribosomal proteins. Analysis of sequence alignment revealed several highly conserved domains, one of which is related to nuclear localization signal (NLS) region of human rpS7. Interestingly, intron nucleotide sequence comparison with A. gambiae showed a lesser degree of conservation as compared to coding and untranslated regions. Like this, early studies on the genomic organization and cDNA/Expressed sequence tag analysis (EST) could help in genome annotation ofA. stephensi, and would be likely to be sequenced in the future.

  10. Green synthesis of silver nanoparticles using Murraya koenigii leaf extract against Anopheles stephensi and Aedes aegypti.

    Science.gov (United States)

    Suganya, Ayyappan; Murugan, Kadarkarai; Kovendan, Kalimuthu; Mahesh Kumar, Palanisamy; Hwang, Jiang-Shiou

    2013-04-01

    Mosquitoes transmit serious human diseases, causing millions of deaths every year. The use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of synthesized natural products for vector control have been a priority in this area. In the present study, the activity of silver nanoparticles (AgNPs) synthesized using Murraya koenigii plant leaf extract against first to fourth instars larvae and pupae of Anopheles stephensi and Aedes aegypti was determined. Range of concentrations of synthesized AgNPs (5, 10, 20, 30, and 40 ppm) and ethanol leaf extract (50, 200, 350, 500, and 650 ppm) were tested against the larvae of A. stephensi and A. aegypti. The synthesized AgNPs from M. koenigii leaf were highly toxic than crude leaf ethanol extract in both mosquito species. The results were recorded from UV-Vis spectrum, Fourier transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy analysis. Larvae were exposed to varying concentrations of aqueous extract of synthesized AgNPs for 24 h. The maximum mortality was observed in synthesized AgNPs, and ethanol leaf extract of M. koenigii against A. stephensi had LC50 values of 10.82, 14.67, 19.13, 24.35, and 32.09 ppm and 279.33, 334.61, 406.95, 536.11, and 700.16 ppm and LC90 values of 32.38, 42.52, 53.65, 63.51, and 75.26 ppm and 737.37, 843.84, 907.67, 1,187.62, and 1,421.13 ppm. A. aegypti had LC50 values of 13.34, 17.19, 22.03, 27.57, and 34.84 ppm and 314.29, 374.95, 461.01, 606.50, and 774.01 ppm and LC90 values of 36.98, 47.67, 55.95, 67.36, and 77.72 ppm and 777.32, 891.16, 1,021.90, 1,273.06, and 1,509.18 ppm, respectively. These results suggest that the use of M. koenigii synthesized silver nanoparticles can be a rapid, environmentally safer biopesticide which can form a novel approach to develop effective biocides for controlling the target

  11. Aristolochia indica green-synthesized silver nanoparticles: A sustainable control tool against the malaria vector Anopheles stephensi?

    Science.gov (United States)

    Murugan, Kadarkarai; Labeeba, Mohammed Aamina; Panneerselvam, Chellasamy; Dinesh, Devakumar; Suresh, Udaiyan; Subramaniam, Jayapal; Madhiyazhagan, Pari; Hwang, Jiang-Shiou; Wang, Lan; Nicoletti, Marcello; Benelli, Giovanni

    2015-10-01

    Malaria is a life-threatening disease caused by parasites transmitted to people and animals through the bites of infected mosquitoes. We biosynthesized silver nanoparticles (AgNP) using Aristolochia indica extract as reducing and stabilizing agent. AgNP were characterized by UV-vis spectroscopy, FTIR, SEM, EDX and XRD. In laboratory, LC50 of A. indica extract against Anopheles stephensi ranged from 262.66 (larvae I) to 565.02 ppm (pupae). LC50 of AgNP against A. stephensi ranged from 3.94 (larvae I) to 15.65 ppm (pupae). In the field, the application of A. indica extract and AgNP (10 × LC50) leads to 100% larval reduction after 72 h. In laboratory, 24-h predation efficiency of Diplonychus indicus against A. stephensi larvae was 33% (larvae II) and 57% (larvae III). In AgNP-contaminated environment (1 ppm), it was 45.5% (larvae II) and 71.75% (larvae III). Overall, A. indica-synthesized AgNP may be considered as newer and safer control tools against Anopheles vectors.

  12. Larvicidal activities of Knema attenuata (Hook. f. & Thomson) Warb. (Myristicaceae) extracts against Aedes albopictus Skuse and Anopheles stephensi Liston.

    Science.gov (United States)

    Vinayachandra; Shwetha, R; Chandrashekar, K R

    2011-12-01

    In recent years, uses of environment friendly and biodegradable natural insecticides of plant origin have received renewed attention as agents for vector control. The present study was undertaken to investigate the effect of aril and kernel extracts of Knema attenuata (Hook. f. & Thomson) Warb. (Myristicaceae) on larvae of Aedes albopictus Skuse and Anopheles stephensi Liston under laboratory conditions. The aril was extracted with chloroform and ethanol; the kernel was extracted with ethanol and hexane. The extracts were tested against the 3rd-4th instar larvae collected from Bunder area, Mangalore, India, which is a well-known fishing harbour, where several mosquito-borne diseases were reported. All the graded concentrations (100, 200, 300, 400 and 500 ppm) showed significant larval mortality after 24 h of observation. Chloroform extracts of aril showed 100% mortality against both larval forms of A. albopictus and A. stephensi at the concentration of 500 ppm. Among the extracts tested, chloroform extracts of aril and ethanol extracts of kernel exhibited higher toxicity against both A. albopictus (LC(50), 141 ppm and 159 ppm; LC(90), 290 ppm and 342 ppm) and A. stephensi (LC(50), 160 ppm and 162 ppm; LC90, 445 ppm and 458 ppm). Hexane extracts of kernel exhibited least toxicity against A. albopictus (LC50, 239 ppm; LC(90), 484 ppm), whereas ethanol extracts of aril showed the least toxicity against A. stephensi (LC(50), 290; LC(90), 498). A preliminary phytochemical assay revealed the presence of phenolics, tannins, steroids, terpenes, resins, and glycolipids in all the extracts. Alkaloids, flavonoids and saponins were absent. The lower LC(50) value of the chloroform extracts of K. attenuata aril indicates its potentiality as a larvicide against A. albopictus and A. stephensi mosquito larvae. PMID:21559763

  13. Competency of Anopheles stephensi mysorensis strain for Plasmodium vivax and the role of inhibitory carbohydrates to block its sporogonic cycle

    Directory of Open Access Journals (Sweden)

    Whitten Miranda MA

    2008-07-01

    Full Text Available Abstract Background Despite the abundance of studies conducted on the role of mosquitoes in malaria transmission, the biology and interaction of Plasmodium with its insect host still holds many mysteries. This paper provides the first study to follow the sporogonic cycle of Plasmodium vivax in a wild insecticide-resistant mysorensis strain of Anopheles stephensi, a major vector of vivax malaria in south-eastern Iran. The study subsequently demonstrates that host-parasite sugar binding interactions are critical to the development of this parasite in the salivary glands of its mosquito host. The identity of the receptors or sugars involved was revealed by a receptor "pre-saturation" strategy in which sugars fed to the mosquitoes inhibited normal host-parasite interactions. Methods Anopheles stephensi mysorensis mosquitoes were artificially infected with P. vivax by feeding on the blood of gametocytaemic volunteers reporting to local malaria clinics in the Sistan-Baluchistan province of south-eastern Iran. In order to determine the inhibitory effect of carbohydrates on sporogonic development, vector mosquitoes were allowed to ingest blood meals containing both gametocytes and added carbohydrates. The carbohydrates tested were GlcNAc, GalNAc, arabinose, fucose, mannose, lactose, glucose and galactose. Sporogonic development was assessed by survival of the parasite at both the oocyst and sporozoite stages. Results Oocyst development was observed among nearly 6% of the fed control mosquitoes but the overall number of mosquitoes exhibiting sporozoite invasion of the salivary glands was 47.5% lower than the number supporting oocysts in their midgut. Of the tested carbohydrates, only arabinose and fucose slightly perturbed the development of P. vivax oocysts at the basal side of the mosquito midgut, and the remaining sugars caused no reductions in oocyst development. Strikingly however, sporozoites were completely absent from the salivary glands of

  14. Larvicidal potential of carvacrol and terpinen-4-ol from the essential oil of Origanum vulgare (Lamiaceae) against Anopheles stephensi, Anopheles subpictus, Culex quinquefasciatus and Culex tritaeniorhynchus (Diptera: Culicidae).

    Science.gov (United States)

    Govindarajan, Marimuthu; Rajeswary, Mohan; Hoti, S L; Benelli, Giovanni

    2016-02-01

    Mosquito-borne diseases represent a deadly threat for millions of people worldwide. However, the use of synthetic insecticides to control Culicidae may lead to resistance, high operational costs and adverse non-target effects. Nowadays, plant-borne mosquitocides may serve as suitable alternative in the fight against mosquito vectors. In this study, the mosquito larvicidal activity of Origanum vulgare (Lamiaceae) leaf essential oil (EO) and its major chemical constituents was evaluated against the malaria vectors Anopheles stephensi and An. subpictus, the filariasis vector Culex quinquefasciatus and the Japanese encephalitis vector Cx. tritaeniorhynchus. The chemical composition of the EO was analyzed by gas chromatography-mass spectroscopy. GC-MS revealed that the essential oil of O. vulgare contained 17 compounds. The major chemical components were carvacrol (38.30%) and terpinen-4-ol (28.70%). EO had a significant toxic effect against early third-stage larvae of An. stephensi, An. subpictus, Cx. quinquefasciatus and Cx. tritaeniorhynchus, with LC50 values of 67.00, 74.14, 80.35 and 84.93 μg/ml. The two major constituents extracted from the O. vulgare EO were tested individually for acute toxicity against larvae of the four mosquito vectors. Carvacrol and terpinen-4-ol appeared to be most effective against An. stephensi (LC50=21.15 and 43.27 μg/ml, respectively) followed by An. subpictus (LC50=24.06 and 47.73 μg/ml), Cx. quinquefasciatus (LC50=26.08 and 52.19 μg/ml) and Cx. tritaeniorhynchus (LC50=27.95 and 54.87 μg/ml). Overall, this research adds knowledge to develop newer and safer natural larvicides against malaria, filariasis and Japanese encephalitis mosquito vectors. PMID:26850541

  15. Characterization of the Rel2-regulated transcriptome and proteome of Anopheles stephensi identifies new anti-Plasmodium factors.

    Science.gov (United States)

    Pike, Andrew; Vadlamani, Alekhya; Sandiford, Simone L; Gacita, Anthony; Dimopoulos, George

    2014-09-01

    Mosquitoes possess an innate immune system that is capable of limiting infection by a variety of pathogens, including the Plasmodium spp. parasites responsible for human malaria. The Anopheles immune deficiency (IMD) innate immune signaling pathway confers resistance to Plasmodium falciparum. While some previously identified Anopheles anti-Plasmodium effectors are regulated through signaling by Rel2, the transcription factor of the IMD pathway, many components of this defense system remain uncharacterized. To begin to better understand the regulation of immune effector proteins by the IMD pathway, we used oligonucleotide microarrays and iTRAQ to analyze differences in mRNA and protein expression, respectively, between transgenic Anopheles stephensi mosquitoes exhibiting blood meal-inducible overexpression of an active recombinant Rel2 and their wild-type conspecifics. Numerous genes were differentially regulated at both the mRNA and protein levels following induction of Rel2. While multiple immune genes were up-regulated, a majority of the differentially expressed genes have no known immune function in mosquitoes. Selected up-regulated genes from multiple functional categories were tested for both anti-Plasmodium and anti-bacterial action using RNA interference (RNAi). Based on our experimental findings, we conclude that increased expression of the IMD immune pathway-controlled transcription factor Rel2 affects the expression of numerous genes with diverse functions, suggesting a broader physiological impact of immune activation and possible functional versatility of Rel2. Our study has also identified multiple novel genes implicated in anti-Plasmodium defense. PMID:24998399

  16. Larvicidal activity of Morinda citrifolia L. (Noni) (Family: Rubiaceae) leaf extract against Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti.

    Science.gov (United States)

    Kovendan, Kalimuthu; Murugan, Kadarkarai; Shanthakumar, Shanmugam Perumal; Vincent, Savariar; Hwang, Jiang-Shiou

    2012-10-01

    Morinda citrifolia leaf extract was tested for larvicidal activity against three medically important mosquito vectors such as malarial vector Anopheles stephensi, dengue vector Aedes aegypti, and filarial vector Culex quinquefasciatus. The plant material was shade dried at room temperature and powdered coarsely. From the leaf, 1-kg powder was macerated with 3.0 L of hexane, chloroform, acetone, methanol, and water sequentially for a period of 72 h each and filtered. The yield of extracts was hexane (13.56 g), chloroform (15.21 g), acetone (12.85 g), methanol (14.76 g), and water (12.92 g), respectively. The extracts were concentrated at reduced temperature on a rotary vacuum evaporator and stored at a temperature of 4°C. The M. citrifolia leaf extract at 200, 300, 400, 500, and 600 ppm caused a significant mortality of three mosquito species. Hexane, chloroform, acetone, and water caused moderate considerable mortality; however, the highest larval mortality was methanolic extract, observed in three mosquito vectors. The larval mortality was observed after 24-h exposure. No mortality was observed in the control. The third larvae of Anopheles stephensi had values of LC(50) = 345.10, 324.26, 299.97, 261.96, and 284.59 ppm and LC(90) = 653.00, 626.58, 571.89, 505.06, and 549.51 ppm, respectively. The Aedes aegypti had values of LC(50) = 361.75, 343.22, 315.40, 277.92, and 306.98 ppm and LC(90) = 687.39, 659.02, 611.35, 568.18, and 613.25 ppm, respectively. The Culex quinquefasciatus had values of LC(50) = 382.96, 369.85, 344.34, 330.42, and 324.64 ppm and LC(90) = 726.18, 706.57, 669.28, 619.63, and 644.47 ppm, respectively. The results of the leaf extract of M. citrifolia are promising as good larvicidal activity against the mosquito vector Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus. This is a new eco-friendly approach for the control of vector control programs. Therefore, this study provides first report on the larvicidal activities against three

  17. Spinosad and neem seed kernel extract as bio-controlling agents for malarial vector,Anopheles stephensi and non-biting midge,Chironomus circumdatus

    Institute of Scientific and Technical Information of China (English)

    Kumar AN; Murugan K; Madhiyazhagan P; Prabhu K

    2011-01-01

    Objective:Midge egg masses are reported to support non-pathogenic strains of the cholera pathogen,Vibrio cholera (V. cholera). Mosquito born diseases have been reported to cause millions of death worldwide. The present research reveals the toxicity effect of spinosad and neem seed kernel extract (NSKE)against different larval stages ofAnopheles stephensi (An. stephensi) andChironomus circumdatus (Ch. circumdatus).Methods: The neem seeds were collected from Marudamalai hills, Bharathiar University, Coimbatore, India. Neem seed kernels were powdered, extracted and diluted for different concentrations (2 ppm to10 ppm). Spinosad was purchased from Kalpatharu pesticide Limited, Coimbatore, Tamil Nadu, India and thoroughly mixed with distilled water to prepare various concentrations (0.01 to0.08 ppm) and used for bioassay.Results: The results depict that spinosad is more toxic in lower concentrations when compared toNSKE and mosquitoes are more susceptible than chironomids. Lethal concentrations were evaluated using the observed mortality. The lowest LC50 value obtained from spinosad againstAn. stephensi and Ch. circumdatus were0.002 05 ppm and0.008 91 ppm. This study investigated on effect of Spinosad andNSKE on the biology of mosquito. The immature stages of both species were susceptible to Spinosad andNSKE. Spinosad andNSKE in individual as well as combined treatment provided additional days in development for mosquitoes.Conclusions:The results conclude that Spinosad andNSKE are potential larvicides against An. stephensi andCh. circumdatus.

  18. Anopheles stephensi: effect of gamma-radiation and chemosterilants on the fertility and fitness of males for sterile male releases

    International Nuclear Information System (INIS)

    Irradiation of Anopheles stephensi Liston male pupae with 8 krad induced 97.2 percent male sterility. Higher irradiation of 12 krad resulted in ca. 2 percent increase of sterility (99.1 percent) with reduced fitness of males for mating and survival. Four krad irradiation of females resulted in inhibited egg production and at 7 krad there was complete failure of females to lay eggs. Thiotepa was not effective in the sterilization of mosquitoes at the pupal stage. Dipping mosquito pupae in 1 percent P, P-bis (1-aziridinyl)-N-methylphosphinothioic amide for 2 h induced 100 percent sterility in both sexes. Chemosterilized males were permanently sterile and comparable in quality (mating competitiveness, mating ability, and survival) with untreated males

  19. Baseline Susceptibility of Different Geographical Strains of Anopheles stephensi (Diptera: Culicidae to Temephos in Malarious Areas of Irana.

    Directory of Open Access Journals (Sweden)

    Aboozar Soltani

    2013-06-01

    Full Text Available Malaria still remains a public health problem in Iran. There are different vector control interventions such as insecticide spraying. The present study was carried out to determine the susceptibility status of Anopheles stephensi larvae to temephos as a national plan for monitoring and mapping of insecticide resistance.Eight different localities in two main malarious provinces were determined as field collecting sites. Mosquitoes were collected from the field and reared in an insectray. Susceptibility assays were carried out according to the WHO method. The laboratory reared susceptible Beech-Lab strain was used for comparison. Data were analyzed using Probit analysis to determine LC50 and LC90 values.Susceptibility of An. stephensi to temephos indicated that the LC50 ranged from 0.0022 mg/l to 0.0141 mg/l. Although all field strains were susceptible to temephos, considerable variations in temephos resistance ratios of field strains were noticed from all the localities studied in comparison with the susceptible strain. A low level of resistance ratio was noticed in An. stephensi populations except for the Chabahar strain (RR= 4.27 fold. All field-collected An. stephensi populations exhibited homogeneity to the larvicide except for Bandar Abbas and Hormoodar village strains (P> 0.05%.Due to intensive use of temephos in the neighboring countries and occurrence of resistant to this insecticide in the main malaria vector in the region, insecticide resistance gene may evolve in the populations of An. stephensi. If temephos be applied as a larvicide it should be used judiciously for resistance management, as rotation strategy.

  20. Chemical Composition and Repellent Activity of Achillea vermiculata and Satureja hortensis against Anopheles stephensi

    OpenAIRE

    Masoumeh Pirmohammadi; Mansoureh Shayeghi; Hassan Vatandoost; Mohammad Reza Abaei; Ali Mohammadi; Akbar Bagheri; Mehdi Khoobdel; Hasan Bakhshi; Maryam Pirmohammadi; Maryam Tavassoli

    2016-01-01

    Background: One of the best ways to control the malaria disease and to be protected human against Anopheles mos­quito biting is the use of repellents. Throughout repellents, herbal ones may be an appropriate and safe source for protection.Methods: Chemical constituents of Achillea vermiculata and Satoreja hortensis were determined by using gas chromatography-mass spectrometry. Efficacy and the protection time of these plants were assessed on Anopheles stephensi under the laboratory condition....

  1. Silencing of Anopheles stephensi Heme Peroxidase HPX15 Activates Diverse Immune Pathways to Regulate the Growth of Midgut Bacteria.

    Science.gov (United States)

    Kajla, Mithilesh; Choudhury, Tania P; Kakani, Parik; Gupta, Kuldeep; Dhawan, Rini; Gupta, Lalita; Kumar, Sanjeev

    2016-01-01

    Anopheles mosquito midgut harbors a diverse group of endogenous bacteria that grow extensively after the blood feeding and help in food digestion and nutrition in many ways. Although, the growth of endogenous bacteria is regulated by various factors, however, the robust antibacterial immune reactions are generally suppressed in this body compartment by a heme peroxidase HPX15 crosslinked mucins barrier. This barrier is formed on the luminal side of the midgut and blocks the direct interactions and recognition of bacteria or their elicitors by the immune reactive midgut epithelium. We hypothesized that in the absence of HPX15, an increased load of exogenous bacteria will enormously induce the mosquito midgut immunity and this situation in turn, can easily regulate mosquito-pathogen interactions. In this study, we found that the blood feeding induced AsHPX15 gene in Anopheles stephensi midgut and promoted the growth of endogenous as well as exogenous fed bacteria. In addition, the mosquito midgut also efficiently regulated the number of these bacteria through the induction of classical Toll and Imd immune pathways. In case of AsHPX15 silenced midguts, the growth of midgut bacteria was largely reduced through the induction of nitric oxide synthase (NOS) gene, a downstream effector molecule of the JAK/STAT pathway. Interestingly, no significant induction of the classical immune pathways was observed in these midguts. Importantly, the NOS is a well known negative regulator of Plasmodium development, thus, we proposed that the induction of diverged immune pathways in the absence of HPX15 mediated midgut barrier might be one of the strategies to manipulate the vectorial capacity of Anopheles mosquito. PMID:27630620

  2. RESISTANCE OF ANOPHELES STEPHENSI LISTON TO MALATHION IN THE PROVICE OF FARS, SOUTHERN IRAN

    Directory of Open Access Journals (Sweden)

    N.Eshghy

    1985-08-01

    Full Text Available Anopheles Stephensi is an important malaria vector in southern Iran. This species developed resistance to DDT in 1975 and subsequently to dieldrin in 1960. Since 1968 this species has been under pressure of malathin house sprayin. 50% w.d.p. , 2g/m2, 1-2 rounds per year. Susceptibility tests carried out with malathion impregnated papers during 1979 showed that An.stephensi has acquired resistant to malathion too. With regard to the 0.1% propoxur, a study was carried out to obtain base-line data in the localities under routine observations and also the discriminating dosage that could kill 100% of An.stephensi. The objective of the present paper is to summarize and discuss briefly the field investigations concerning insecticide resistance in An.stephensi.

  3. Adulticidal and repellent properties of Cassia tora Linn. (Family: Caesalpinaceae) against Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi.

    Science.gov (United States)

    Amerasan, Duraisamy; Murugan, Kadarkarai; Kovendan, Kalimuthu; Mahesh Kumar, Palanisamy; Panneerselvam, Chellasamy; Subramaniam, Jayapal; John William, Samuel; Hwang, Jiang-Shiou

    2012-11-01

    Mosquitoes have developed resistance to various synthetic insecticides, making its control increasingly difficult. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. The adulticidal and repellent activities of crude hexane, chloroform, benzene, acetone, and methanol extracts of the leaf of Cassia tora were assayed for their toxicity against three important vector mosquitoes, viz., Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi. The adult mortality was observed after 24 h of exposure. All extracts showed moderate adulticidal effects; however, the highest adult mortality observed was found in methanol extract. The LC(50) and LC(90) values of C. tora leaf extracts against adulticidal activity of (hexane, chloroform benzene, acetone, and methanol) C. quinquefasciatus, A. aegypti, and A. stephensi were the following: C. quinquefasciatus LC(50) values were 338.81, 315.73, 296.13, 279.23, and 261.03 ppm and LC(90) values were 575.77, 539.31, 513.99, 497.06, and 476.03 ppm; A. aegypti LC(50) values were 329.82, 307.31, 287.15, 269.57, and 252.03 ppm and LC(90) values were 563.24, 528.33, 496.92, 477.61, and 448.05 ppm; and A. stephensi LC(50) values were 317.28, 300.30, 277.51, 263.35, and 251.43 ppm and LC(90) values were 538.22, 512.90, 483.78, 461.08, and 430.70 ppm, respectively. The results of the repellent activity of hexane, chloroform, benzene, acetone, and methanol extracts of C. tora plant at three different concentrations of 1.0, 2.5, and 5.0 mg/cm(2) were applied on skin of forearm in man and exposed against adult female mosquitoes. In this observation, this plant crude extracts gave protection against mosquito bites without any allergic reaction to the test person, and also, the repellent activity is dependent on the strength of the plant extracts. These results suggest that the leaf solvent plant extracts have the potential to be used as an ideal eco-friendly approach for the control of

  4. Bioefficacy of Morinda tinctoria and Pongamia glabra plant extracts against the malaria vector Anopheles stephensi (Diptera: Culicidae

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    D. Amerasan

    2015-04-01

    Full Text Available Mosquito-borne diseases have an economic impact, including loss in commercial and labour outputs, particularly in countries with tropical and subtropical climates; however, no part of the world is free from vector-borne diseases. The aim of the present study was to investigate the larvicidal, adulticidal and ovicidal activity of dried leaf chloroform, ethyl acetate, acetone, aqueous, and methanol extracts of Morinda tinctoria and Pongamia glabra against larvae of Anopheles stephensi (Diptera: Culicidae. Larvae were exposed to varying concentrations of plant extracts for 24 h. All extracts showed moderate larvicidal effects after 24 h of exposure; however, the highest larval mortality was found with the leaf methanol extracts of M. tinctoria and P. glabra against the larvae of A. stephensi lethal concentration (LC50=136.24 and 141.05 ppm; LC90=342.67 and 368.89 ppm, respectively. The results of the adulticidal activity assays of chloroform, ethyl acetate, acetone, aqueous, and methanol extracts of M. tinctoria and P. glabra showed significant mortality against larvae of A. stephensi. The methanol extract showed maximum activity compared with the other extracts. The greatest effect on mean percentage hatch in the ovicidal assays was observed 48 h post-treatment. Percent hatch was inversely proportional to the concentration of extract, and directly proportional to the number of eggs. A mortality of 100% was observed with 100-400 ppm methanol extracts and 200-400 ppm aqueous extracts of M. tinctoria, and 200-400 ppm aqueous and methanol extracts of P. glabra. This study provides the first report of the larvicidal, adulticidal and ovicidal activities of M. tinctoria and P. glabra plant extracts against the malaria vector, A. stephensi, representing an ideal eco-friendly approach for its control.

  5. Mosquitocidal activity of indigenenous plants of Western Ghats, Achras sapota Linn. (Sapotaceae) and Cassia auriculata L. (Fabaceae) against a common malarial vector, Anopheles stephensi Liston (Culicidae:Diptera)

    Institute of Scientific and Technical Information of China (English)

    Kaliyamoorthy Krishnappa; Kuppusamy Elumalai

    2014-01-01

    Objective: To evaluate the mosquito larvicidal, ovicidal, pupicidal and repellent activities of hexane, diethyl ether, dichloromethane, acetone and methanol extracts of Indian medicinal plants, Achras sapota (A. sapota) and Cassia auriculata (C. auriculata) at different concentrations against Anopheles stephensi (An. stephensi), a malarial vector. Methods: Twenty five early third instar larvae of An. stephensi were exposed to various concentrations (30-210 mg/L) of plants extracts and were assayed in the laboratory by using the protocol of WHO 2005;then after 24 h LC50 values of the A. sapota and C. auriculata leaf extract was determined by probit analysis. The ovicidal activity was tested with the extracts ranging from 50-350 mg/L. The pupicidal activity was recorded after 24 h of exposure to the extract. The repellent efficacy was determined against mosquito species at two different concentrations 1.5 and 3.0 mg/cm2 under laboratory conditions. Results:Among the five different extracts tested against the An. stephensi, methanol extract of A. sapota proved to be an more effective solvent extract in almost all the parameters studied than C. auriculata. Conclusions:It is inferred that the leaf extract of A. sapota and C. auriculata could be used in vector control programme.

  6. Larvicidal and repellent potential ofMoringa oleiferaagainst malarial vector,Anopheles stephensi Liston (Insecta:Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Prabhu K; Murugan K; Nareshkumar A; Ramasubramanian N; Bragadeeswaran S

    2011-01-01

    Objective:To evaluate the larvicidal and pupicidal potential of the methanolic extracts from Moringa oleifera (M. oleifera) plant seeds against malarial vectorAnopheles stephensi(A. stephensi) mosquitoes at different concentrations (20,40,60,80 and100 ppm).Methods:M. oleifera was collected from the area of around Bharathiar University, Coimbatore. The dried plant materials were powdered by an electrical blender. From each sample,100 g of the plant material were extracted with300 mL of methanol for8 h in a Soxhlet apparatus. The extracts were evaporated to dryness in rotary vacuum evaporator to yield122 mg and110 mg of dark greenish material (residue) fromArcang amara andOcimum basilicum, respectively. One gram of the each plant residue was dissolved separately in100 mL of acetone (stock solution) from which different concentrations, i.e.,20,40,60,80 and100 ppm were prepared.Results: Larvicidal activity ofM.oleifera exhibited in the first to fourth instar larvae of theA. stephensi, and the LC50 and LC90 values were57.79 ppm and125.93 ppm for the first instar,63.90 ppm and133.07 ppm for the second instar,72.45 ppm and139.82 ppm for the third instar,78.93 ppm and143.20 ppm for the fourth instar, respectively. During the pupal stage the methanolic extract ofM.oleifera showed that the LC50 and LC90 values were67.77 ppm and141.00 ppm, respectively.Conclusions:The present study indicates that the phytochemicals derived fromM. oleifera seeds extracts are effective mosquito vector control agents and the plant extracts may be used for further integrated pest management programs.

  7. Ecology of Anopheles stephensi in a malarious area, southeast of Iran.

    Science.gov (United States)

    Mehravaran, Ahmad; Vatandoost, Hassan; Oshaghi, Mohammad Ali; Abai, Mohammad Reza; Edalat, Hamideh; Javadian, Ezatoddin; Mashayekhi, Minoo; Piazak, Norair; Hanafi-Bojd, Ahmad Ali

    2012-01-01

    District of Jiroft is situated in south-east of Iran which is one of the malarious regions. Anopheles stephensi is considered as one of the main malaria vector in this region. Ecology of this species was studied in the area to understand its vector behavior for implementation of effective vector control measures. Different methods like total catch, pit shelter, night bite collection on human and animal, larval dipping methods were used for species identification, seasonal activity, anthropophilic index and egg morphological characteristics. Anthropophilicity index was assessed by ELISA test. Activity of Anopheles species started at the beginning of April, and its peak occurs in late spring. The larvae were found in the river bed with pools, stagnant streams, slow foothill streams, temporary pools, and slowly moving water with and without vegetation, drainage containers of air conditioner and palm irrigation canals. From different methods of adult collection, it was found that spray sheet collection is the appropriate method. ELISA testing of 144 blood meals of females revealed the anthropophilicity of 11.8% indicating host preference on animal, mainly cow. Ridge length and their number on the egg floats confirmed Anopheles stephensi mysorensis form. This study showed that Anopheles stephensi is the main vector of malaria in the region, although some other species may play a role. Our findings could provide a valuable clue for epidemiology and control of malaria in the southeast of Iran. PMID:22267381

  8. Ecology of Anopheles Stephensi in a Malarious Area, Southeast of Iran

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    Norair Piazak

    2012-01-01

    Full Text Available District of Jiroft is situated in south-east of Iran which is one of the malarious regions. Anopheles stephensi is considered as one of the main malaria vector in this region. Ecology of this species was studied in the area to understand its vector behavior for implementation of effective vector control measures. Different methods like total catch, pit shelter, night bite collection on human and animal, larval dipping methods were used for species identification, seasonal activity, anthropophilic index and egg morphological characteristics. Anthropophilicity index was assessed by ELISA test. Activity of Anopheles species started at the beginning of April, and its peak occurs in late spring. The larvae were found in the river bed with pools, stagnant streams, slow foothill streams, temporary pools, and slowly moving water with and without vegetation, drainage containers of air conditioner and palm irrigation canals. From different methods of adult collection, it was found that spray sheet collection is the appropriate method. ELISA testing of 144 blood meals of females revealed the anthropophilicity of 11.8% indicating host preference on animal, mainly cow. Ridge length and their number on the egg floats confirmed Anopheles stephensi mysorensis form. This study showed that Anopheles stephensi is the main vector of malaria in the region, although some other species may play a role. Our findings could provide a valuable clue for epidemiology and control of malaria in the southeast of Iran.

  9. Larvicidal, ovicidal and repellent activities of marine spongeCliona celata (Grant) extracts againstAnopheles stephensi Liston (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Appadurai Daniel Reegan; Arokia Valan Kinsalin; Michael Gabriel Paulraj; Savarimuthu Ignacimuthu

    2015-01-01

    Objective:To evaluate the larvicidal, ovicidal and repellent properties of solvent extracts of marine spongeCliona celata(C. celata)(Grant) against the malarial vectorAnopheles stephensi(An. stephensi)Liston.Methods:Marine spongeC. celata was thoroughly washed with distilled water and shade dried for48 h.Then the sponges were homogenized and extracted sequentially with hexane, ethyl acetate and methanol.Larvicidal and ovicidal activities were tested at four different concentrationsviz.,62.5,125.0,250.0 and500.0 ppm.For repellent study extracts were taken in three different concentrationsviz.,5.0,2.5,1.0 mg/cm2 at.Results:Among the three solvent extracts ofC. celata, methanol extract showed the highest larvicidal activity at500 ppm against the fourth instar larvae ofAn. stephensi.TheLC50andLC90 values ofC. celata methanol extract were recorded as80.61 and220.81 ppm againstAn. stephensi larvae respectively.High ovicidal activity of91.2% was recorded at500 ppm concentration of methanol extract.The haxane extract was found to be the most effective protectant against the adult female mosquitoes ofAn. stephensi. The mean protection time recorded in hexane extract was up to245 min at5 mg/cm2 dosage againstAn. stephensi adults.Conclusions:The screening results suggest that the hexane and methanol extracts ofC. celata are promising in mosquito control.Considering these bioactivities,C. celata could be probed further to obtain some novel pesticidal molecules.

  10. PROPOXUR SELECTION OF THE ADULTS OF ANOPHELES STEPHENSI FROM MINAB, SOUTH OF IRAN

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    H. Edalat

    1997-10-01

    Full Text Available Anopheles stephensi is the main malaria vector in south of Iran. It has been known to be resistant to DDT, malathion and dieldrin. After appearance of resistance the area was treated with propoxur, at the rate of 2 g/m2 twice a year for 14 successive years. This species is still susceptible to propoxur. In order to forecast the possibility of development of propoxur resistance in An.stephensi, the females of this species were put under the pressure of propoxur for 14 generations in 1988. Fourteen generations of propoxur selection on the adult females of An.stephensi resulted in an increase in LT60 from 8.5 min to 24.30 minutes, i.e. 2.86 fold increase in tolerance.

  11. Ecology of Anopheles Stephensi in a Malarious Area, Southeast of Iran

    OpenAIRE

    Norair Piazak; Minoo Mashayekhi; Ezatoddin Javadian; Hamideh Edalat; Mohammad Reza Abai; Mohammad Ali Oshaghi; Hassan Vatandoost; Ahmad Mehravaran; Ahmad Ali Hanafi-Bojd

    2012-01-01

    District of Jiroft is situated in south-east of Iran which is one of the malarious regions. Anopheles stephensi is considered as one of the main malaria vector in this region. Ecology of this species was studied in the area to understand its vector behavior for implementation of effective vector control measures. Different methods like total catch, pit shelter, night bite collection on human and animal, larval dipping methods were used for species identification, seasonal activity, anthropoph...

  12. Green chemistry focus on optimization of silver nanoparticles using response surface methodology (RSM) and mosquitocidal activity: Anopheles stephensi (Diptera: Culicidae).

    Science.gov (United States)

    Ondari Nyakundi, Erick; Padmanabhan, M Nalini

    2015-01-01

    There is an exigent necessity for development of environmental friendly bio-control agent(s) for elimination of mosquito due to increased resistance resurgence against synthetic control agents. Mosquito control strategy will lay a strong foundation to malaria exclusion or it can be curbed to certain level especially in the developing nations. In this study, silver nanoparticles were synthesized by green chemistry approach using Tridax procumbens leaf extract as a reducing agent. The reaction medium involved in the synthesis process was optimized by statistical experimental design using response surface methodology to obtain better yield, uniform size, shape and stability. Further, these synthesized nanoparticles were confirmed through UV-Visible, FT-IR spectroscopy, PSA and SEM Subsequently, the bioefficacy of these particles were investigated on Anopheles stephensi for larvicidal and pupicidal activity. Interestingly, time period of 90 min, temperature of 76±2 °C, pH 7.2±2, 2 mM silver nitrate (AgNO3), 3mM PEG and 2mM PVP showed excellent parameters for bioprocess design for large scale production of stabilized nanoparticles. A concentration of 5 ppm of PVP stabilized nanoparticles exhibited 100% mortality. Thus, the obtained results clearly suggest that silver nanoparticles stabilized by PEG and PVP may have important function as stabilizers, dispersants as well as larvicides for mosquito control.

  13. Green chemistry focus on optimization of silver nanoparticles using response surface methodology (RSM) and mosquitocidal activity: Anopheles stephensi (Diptera: Culicidae).

    Science.gov (United States)

    Ondari Nyakundi, Erick; Padmanabhan, M Nalini

    2015-01-01

    There is an exigent necessity for development of environmental friendly bio-control agent(s) for elimination of mosquito due to increased resistance resurgence against synthetic control agents. Mosquito control strategy will lay a strong foundation to malaria exclusion or it can be curbed to certain level especially in the developing nations. In this study, silver nanoparticles were synthesized by green chemistry approach using Tridax procumbens leaf extract as a reducing agent. The reaction medium involved in the synthesis process was optimized by statistical experimental design using response surface methodology to obtain better yield, uniform size, shape and stability. Further, these synthesized nanoparticles were confirmed through UV-Visible, FT-IR spectroscopy, PSA and SEM Subsequently, the bioefficacy of these particles were investigated on Anopheles stephensi for larvicidal and pupicidal activity. Interestingly, time period of 90 min, temperature of 76±2 °C, pH 7.2±2, 2 mM silver nitrate (AgNO3), 3mM PEG and 2mM PVP showed excellent parameters for bioprocess design for large scale production of stabilized nanoparticles. A concentration of 5 ppm of PVP stabilized nanoparticles exhibited 100% mortality. Thus, the obtained results clearly suggest that silver nanoparticles stabilized by PEG and PVP may have important function as stabilizers, dispersants as well as larvicides for mosquito control. PMID:26010566

  14. Strong larvicidal potential of Artemisia annua leaf extract against malaria (Anopheles stephensi Liston) and dengue (Aedes aegypti L.) vectors and bioassay-driven isolation of the marker compounds.

    Science.gov (United States)

    Sharma, Gaurav; Kapoor, Himanshi; Chopra, Madhu; Kumar, Kaushal; Agrawal, Veena

    2014-01-01

    Malaria and dengue are the two most important vector-borne human diseases caused by mosquito vectors Anopheles stephensi and Aedes aegypti, respectively. Of the various strategies adopted for eliminating these diseases, controlling of vectors through herbs has been reckoned as one of the important measures for preventing their resurgence. Artemisia annua leaf chloroform extract when tried against larvae of A. stephensi and A. aegypti has shown a strong larvicidal activity against both of these vectors, their respective LC50 and LC90 values being 0.84 and 4.91 ppm for A. stephensi and 0.67 and 5.84 ppm for A. aegypti. The crude extract when separated through column chromatography using petroleum ether-ethyl acetate gradient (0-100%) yielded 76 fractions which were pooled into three different active fractions A, B and C on the basis of same or nearly similar R f values. The aforesaid pooled fractions when assayed against the larvae of A. stephensi too reported a strong larvicidal activity. The respective marker compound purified from the individual fractions A, B and C, were Artemisinin, Arteannuin B and Artemisinic acid, as confirmed and characterized through FT-IR and NMR. This is our first report of strong mortality of A. annua leaf chloroform extract against vectors of two deadly diseases. This technology can be scaled up for commercial exploitation. PMID:24158647

  15. Phenotypic dissection of a Plasmodium-refractory strain of malaria vector Anopheles stephensi: the reduced susceptibility to P. berghei and P. yoelii.

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    Naoaki Shinzawa

    Full Text Available Anopheline mosquitoes are the major vectors of human malaria. Parasite-mosquito interactions are a critical aspect of disease transmission and a potential target for malaria control. Current investigations into parasite-mosquito interactions frequently assume that genetically resistant and susceptible mosquitoes exist in nature. Therefore, comparisons between the Plasmodium susceptibility profiles of different mosquito species may contribute to a better understanding of vectorial capacity. Anopheles stephensi is an important malaria vector in central and southern Asia and is widely used as a laboratory model of parasite transmission due to its high susceptibility to Plasmodium infection. In the present study, we identified a rodent malaria-refractory strain of A. stephensi mysorensis (Ehime by comparative study of infection susceptibility. A very low number of oocysts develop in Ehime mosquitoes infected with P. berghei and P. yoelii, as determined by evaluation of developed oocysts on the basal lamina. A stage-specific study revealed that this reduced susceptibility was due to the impaired formation of ookinetes of both Plasmodium species in the midgut lumen and incomplete crossing of the midgut epithelium. There were no apparent abnormalities in the exflagellation of male parasites in the ingested blood or the maturation of oocysts after the rounding up of the ookinetes. Overall, these results suggest that invasive-stage parasites are eliminated in both the midgut lumen and epithelium in Ehime mosquitoes by strain-specific factors that remain unknown. The refractory strain newly identified in this report would be an excellent study system for investigations into novel parasite-mosquito interactions in the mosquito midgut.

  16. PCR detection of malaria parasites in desiccated Anopheles mosquitoes is uninhibited by storage time and temperature

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    Rider Mark A

    2012-06-01

    Full Text Available Abstract Background Reliable methods to preserve mosquito vectors for malaria studies are necessary for detecting Plasmodium parasites. In field settings, however, maintaining a cold chain of storage from the time of collection until laboratory processing, or accessing other reliable means of sample preservation is often logistically impractical or cost prohibitive. As the Plasmodium infection rate of Anopheles mosquitoes is a central component of the entomological inoculation rate and other indicators of transmission intensity, storage conditions that affect pathogen detection may bias malaria surveillance indicators. This study investigated the effect of storage time and temperature on the ability to detect Plasmodium parasites in desiccated Anopheles mosquitoes by real-time polymerase chain reaction (PCR. Methods Laboratory-infected Anopheles stephensi mosquitoes were chloroform-killed and stored over desiccant for 0, 1, 3, and 6 months while being held at four different temperatures: 28, 37, -20 and -80°C. The detection of Plasmodium DNA was evaluated by real-time PCR amplification of a 111 base pair region of block 4 of the merozoite surface protein. Results Varying the storage time and temperature of desiccated mosquitoes did not impact the sensitivity of parasite detection. A two-way factorial analysis of variance suggested that storage time and temperature were not associated with a loss in the ability to detect parasites. Storage of samples at 28°C resulted in a significant increase in the ability to detect parasite DNA, though no other positive associations were observed between the experimental storage treatments and PCR amplification. Conclusions Cold chain maintenance of desiccated mosquito samples is not necessary for real-time PCR detection of parasite DNA. Though field-collected mosquitoes may be subjected to variable conditions prior to molecular processing, the storage of samples over an inexpensive and logistically

  17. Chemical constituents and larvicidal potential of Feronia limonia leaf essential oil against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus.

    Science.gov (United States)

    Senthilkumar, A; Jayaraman, M; Venkatesalu, V

    2013-03-01

    In the present investigation, the leaf essential oil of Feronia limonia was evaluated for chemical constituents and mosquito larvicidal activity against the larvae of Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus. GC and GC-MS analyses revealed that the essential oil contain 51 compounds. Estragole (34.69 %) and β-pinene(23.59 %) were identified as the major constituents followed by methyl (Z)-caryophyllene (11.05 %), eugenol (6.50 %), linalool (3.97 %), phytol (3.27 %), sabinene (2.41 %) and limonene (2.27 %). Larval mortality was observed after 12 and 24 h of exposure period. The oil showed remarkable larvicidal activity against A. stephensi (LC(50) = 38.93 and LC(90) = 108.64 ppm (after 12 h); LC(50) = 15.03 and LC(90) = 36.69 ppm (after 24 h)), A. aegypti (LC(50) = 37.60 and LC(90) = 104.69 ppm (after 12 h); LC(50) = 11.59 and LC(90) = 42.95 ppm (after 24 h)) and C. quinquefasciatus (LC(50) = 52.08 and LC(90) = 124.33 ppm (after 12 h); LC(50) = 22.49 and LC(90) = 60.90 ppm (after 24 h)). Based on the results, the essential oil of F. limonia can be considered as a new source of larvicide for the control of vector mosquitoes.

  18. Screening of Methanolic Plant Extracts against Larvae of Aedes aegypti and Anopheles stephensi in Mysore

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    Thirumalapura Krishnaiah Mohankumar

    2016-01-01

    Full Text Available Background: Mosquitoes transmit serious human diseases, causing millions of death every year. Vector control is facing a threat due to the emergence of resistance to synthetic insecticides. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. Nine different locally available medicinally important plants suspected to posse larvicidal property were screened against fourth instar larvae of Aedes aegypti and Anoph­eles stephensi to a series of concentrations of the methanolic extracts.Methods: Susceptibility tests on Ae. aegypti and An. stephensi were conducted using standard WHO methods. The larvae of two mosquito species were exposed to methanolic extracts and mortality counts were made after 24 hours of exposure as per WHO method. Larvae of Ae. aegypti were more susceptible than that of An. stephensi.Results: Among the nine plant species tested, Annona reticulata leaf extract was more effective against Ae. aegypti larvae with LC50 and LC90 values of 95.24 and 262.64 ppm respectively and against An. stephensi larvae 262.71 and 636.94 ppm respectively. The least efficacy was in Cosmos bipinnatus with LC50 and LC90 values of 442.6 and 1225.93 ppm against Ae. aegypti and LC50 and LC90 values of 840.69 and 1334.01 ppm of Thespesia populnea against An. stephensi.Conclusion: The crude methanolic extract of the An. reticulata with good larvicidal efficacy could be considered for further characterization to control mosquito vectors instead of chemical insecticides. High efficacy found in An. re­ticulata extract will be considered for further studies to isolate the bioactive compound.

  19. Scanning electron microscopic (Sem studies on fourth instar larva and pupa of Anopheles (Cellia stephensi Liston (Anophelinae: Culicidae

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    Jagbir Singh Kirti

    2014-12-01

    Full Text Available Anopheles (Cellia stephensi Liston is a major vector species of malaria in Indian subcontinent. Taxonomists have worked on its various morphological aspects and immature stages to explore additional and new taxonomic attributes. Scanning electron microscopic (SEM studies have been conducted on the fourth instar larva and pupa of An. stephensi to find additional taxonomic features for the first time from Punjab state.

  20. Low-cost and eco-friendly green synthesis of silver nanoparticles using Feronia elephantum (Rutaceae) against Culex quinquefasciatus, Anopheles stephensi, and Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Veerakumar, Kaliyan; Govindarajan, Marimuthu; Rajeswary, Mohan; Muthukumaran, Udaiyan

    2014-05-01

    Mosquitoes transmit serious human diseases, causing millions of deaths every year. The use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of synthesized natural products for vector control have been a priority in this area. In the present study, the larvicidal activity of silver nanoparticles (AgNPs) synthesized using Feronia elephantum plant leaf extract against late third-instar larvae of Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus was determined. The range of concentrations of synthesized AgNPs (5, 10, 15, 20, and 25 μg mL(-1)) and aqueous leaf extract (25, 50, 75, 100, and 125 μg mL(-1)) were tested against the larvae of A. stephensi, A. aegypti, and C. quinquefasciatus. Larvae were exposed to varying concentrations of aqueous crude extract and synthesized AgNPs for 24 h. Considerable mortality was evident after the treatment of F. elephantum for all three important vector mosquitoes. The synthesized AgNPs from F. elephantum were highly toxic than crude leaf aqueous extract to three important vector mosquito species. The results were recorded from UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy analysis (EDX). Synthesized AgNPs against the vector mosquitoes A. stephensi, A. aegypti, and C. quinquefasciatus had the following LC50 and LC90 values: A. stephensi had LC50 and LC90 values of 11.56 and 20.56 μg mL(-1); A. aegypti had LC50 and LC90 values of 13.13 and 23.12 μg mL(-1); and C. quinquefasciatus had LC50 and LC90 values of 14.19 and 24.30 μg mL(-1). No mortality was observed in the control. These results suggest that the green synthesis of silver nanoparticles using F. elephantum has the potential to be used as an ideal eco-friendly approach for the control of A. stephensi, A. aegypti, and C

  1. Evaluation of leaf aqueous extract and synthesized silver nanoparticles using Nerium oleander against Anopheles stephensi (Diptera: Culicidae).

    Science.gov (United States)

    Roni, Mathath; Murugan, Kadarkarai; Panneerselvam, Chellasamy; Subramaniam, Jayapal; Hwang, Jiang-Shiou

    2013-03-01

    ppm; and LC(50) and LC(90) of pupae 39.55 and 79.10 ppm, respectively. The aqueous leaf extract exhibited larval toxicity against the first to fourth instar larvae and pupae of Anopheles stephensi with the following values: LC(50) of instar larvae 232.90, 273.71, 318.94, and 369.96 ppm; LC(90) of instar larvae 455.95, 563.10, 639.86, and 730.30 ppm; and LC(50) and LC(90) of pupae 426.01 and 805.13 ppm, respectively. The chi-square value was significant at p nanoparticles through a membrane. The results could suggest that the use of plant N. oleander to synthesize silver nanoparticles is a rapid, environmentally safer, and greener approach for mosquito control. This could lead us to a new possibility in vector-control strategy.

  2. COMPARATIVE TOXICITIES OF FOUR WHO-RECOMMENDED LARVICIDES AGAINST LAB STRAIN OF ANOPHELES STEPHENSI IN IRAN

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    H. Vatandoost

    1999-08-01

    Full Text Available Investigation on the current response of An.stephensi larvae to four WHO recommended larvicides, i.e. Malathion, temephos, chlorpyrifos and fenitrothion, were carried out in the laboratory in 1999. Diagnostic concentrations of pesticides only yielded 100% mortality with malathion. In contrast, levels of susceptibility to temphos, chlorpyrifos (0.025 mg/l and temephos (0.625 mg/l killed 72%, 90% and 87% of the population of An. Stephensi, respectively. At the LC50 level the efficacies of chlorpyrifos and fenitrothion was higher than malathion and temephos. Relative toxicity of chlorpyrifos and fenitrothion was 6 and 24 times more than temephos and Malathion. The findings of this study suggest that the diagnostic dose of organophosphate larvicides depends on time, location, strain and genetically background of resistance to insecticides; hence they can be attributed to all species of anopheles.

  3. Screening of Methanolic Plant Extracts against Larvae of Aedes aegypti and Anopheles stephensi in Mysore

    OpenAIRE

    Thirumalapura Krishnaiah Mohankumar; Kumuda Sathigal Shivanna; Vijayan Valiakottukal Achuttan

    2016-01-01

    Background: Mosquitoes transmit serious human diseases, causing millions of death every year. Vector control is facing a threat due to the emergence of resistance to synthetic insecticides. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. Nine different locally available medicinally important plants suspected to posse larvicidal property were screened against fourth instar larvae of Aedes aegypti and Anoph­eles stephensi to a series of co...

  4. Datura metel-synthesized silver nanoparticles magnify predation of dragonfly nymphs against the malaria vector Anopheles stephensi.

    Science.gov (United States)

    Murugan, Kadarkarai; Dinesh, Devakumar; Kumar, Prabhu Jenil; Panneerselvam, Chellasamy; Subramaniam, Jayapal; Madhiyazhagan, Pari; Suresh, Udaiyan; Nicoletti, Marcello; Alarfaj, Abdullah A; Munusamy, Murugan A; Higuchi, Akon; Mehlhorn, Heinz; Benelli, Giovanni

    2015-12-01

    Malaria is a life-threatening disease caused by parasites transmitted to people and animals through the bites of infected mosquitoes. The employ of synthetic insecticides to control Anopheles populations leads to high operational costs, non-target effects, and induced resistance. Recently, plant-borne compounds have been proposed for efficient and rapid extracellular synthesis of mosquitocidal nanoparticles. However, their impact against predators of mosquito larvae has been poorly studied. In this study, we synthesized silver nanoparticles (AgNPs) using the Datura metel leaf extract as reducing and stabilizing agent. The biosynthesis of AgNPs was confirmed analyzing the excitation of surface plasmon resonance using ultraviolet-visible (UV-vis) spectroscopy. Scanning electron microscopy (SEM) showed the clustered and irregular shapes of AgNPs, with a mean size of 40-60 nm. The presence of silver was determined by energy-dispersive X-ray (EDX) spectroscopy. Fourier transform infrared (FTIR) spectroscopy analysis investigated the identity of secondary metabolites, which may be acting as AgNP capping agents. In laboratory, LC50 of D. metel extract against Anopheles stephensi ranged from 34.693 ppm (I instar larvae) to 81.500 ppm (pupae). LC50 of AgNP ranged from 2.969 ppm (I instar larvae) to 6.755 ppm (pupae). Under standard laboratory conditions, the predation efficiency of Anax immaculifrons nymphs after 24 h was 75.5 % (II instar larvae) and 53.5 % (III instar larvae). In AgNP-contaminated environment, predation rates were boosted to 95.5 and 78 %, respectively. Our results documented that D. metel-synthesized AgNP might be employed at rather low doses to reduce larval populations of malaria vectors, without detrimental effects on behavioral traits of young instars of the dragonfly Anax immaculifrons.

  5. Larvicidal,ovicidal and repellent activities of marine sponge Cliona celata(Grant) extracts against Anopheles stephensi Liston(Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Appadurai; Daniel; Reegan; Arokia; Valan; Kinsalin; Michael; Gabriel; Paulraj; Savarimuthu; Ignacimuthu

    2015-01-01

    Obective:To evaluate the larvieidal.ovieidal and repellent properties of solvent extracts of marine sponge Cliona celala(C.celata)(Grant) against the malarial vector Anopheles stephensi(An.stephensi) Listen.Methods:Marine sponge C.celala was thoroughly washed with distilled water and shade dried for 48 h.Then the sponges were homogenized and extracted sequentially with hexane,ethyl acetate and methanol,Lanvicidal and ovicidal activities were tested at four different concentrations viz.,62.5.125.0.250.0 and 500.0 ppm.for repellent study extracts were taken in three different concentrations viz..5.0.2.5.1.0 mg/cm at.Results:Among the three solvent extracts of C.celata,methanol extract showed thc highest lanvieidal activity at 500 ppm against the fourth inslar larvae of An.stephensi.The LC50and LC90 values of C.celata methanol extract were recorded as 80.61 and 220.81 ppm against An.stephensi larvae respectively.High ovieidal activity of 91.2%was recorded al 500 ppm concentration of methanol extract.The haxane extract was found to be the most effective protectant against the adult female mosquitoes of An.stephensi.The mean protection time recorded in hexane extract was up to 245 min at 5 mg/cm2 dosage against An.Stephensi adults.Conclusions:The screening results suggest that the hexane and methanol extracts of C.celata arc promising in mosquito control.Considering these bioaclivitics.C.celata could the probed further to obtain some novel pesticidal molecules.

  6. Larvicidal activity of essential oil and methanol extract of Nepeta menthoides against malaria vector Anopheles stephensi

    Institute of Scientific and Technical Information of China (English)

    Khanavi Mahnaz; Fallah Alireza; Vatandoost Hassan; Sedaghat Mahdi; Abai Mohammad Reza; Hadjiakhoondi Abbas

    2012-01-01

    Objective: To investigate the larvicidal activity of essential oil and methanol extract of theNepeta menthoides (N. menthoides) against main malaria vector, Anopheles stephensi (An. stephensi). Methods: The essential oil of plant was obtained by Clevenger type apparatus and the methanol extract was supplied with Percolation method. Larvicidal activity was tested by WHO method. Twenty five fourth-instar larvae of An. stephensi were used in the larvicidal assay and four replicates were tested for each concentration. Five different concentrations of the oil and extract were tested for calculation of LC50 and LC90 values. Results: The LC50 and LC90 values were determined by probit analysis. LC50 was 69.5 and 234.3 ppm and LC90 was 175.5 and 419.9 ppm for the extract and essential oil respectively. Conclusions: According to the results of this study methanolic extract of plant exhibited more larvicidal activity than essential oil. This could be useful for investigation of new natural larvicidal compounds.

  7. Adulticidal Activity of Olea vera, Linum usitatissimum and Piper nigera against Anopheles stephensi and Aedes aegypti under Laboratory Conditions

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    R Nawaz

    2011-12-01

    Conclusion: Black pepper showed best results in term of LC50, LC90, LT50 and percentage mortality against Ae. ae­gypti and An. stephensi. Our study suggested that the plant extracts have potential to kill adult mosquitoes, are envi­ronment friendly and can be used for the control of mosquitoes.

  8. Wash Resistance and Bioefficacy of Alpha-cypermethrin Long Lasting Impregnated Nets (LLIN-Interceptor(® against Anopheles stephensi using Tunnel Test.

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    Hassan Vatandoost

    2013-06-01

    Full Text Available The Long-lasing insecticide impregnated nets (LLINs is considered as an effective tools for malaria vector control. The aim of this study was to evaluate the residual efficacy of alpha-cypermethrin long lasting impregnated nets (LLIN-Interceptor(® against Anopheles stephensi using tunnel test.The wash-resistance of Interceptor(® nets were assessed under laboratory conditions using tunnel test. Females of An. stephensi were released into the tunnel and then they were provided blood meals from guinea pigs. Bed nets were washed according to the standard procedure up to 20 times. The bioefficacy indicators such as inhibition of bloodmeal from experimental animal, knockdown, irritancy rate, survival rate, entry index and mortality were calculated.It induced 90-100% mortalities in the population of An. stephensi up to 15 washes. The KT50 values reduced from 73.47 to 26.30 minutes in unwashed in comparison to one washed, respectively. The mean of mortality rate of blood-feeding inhibition and entry indexes was reached to 91.6%±2.8, 87.0±3.4 and 24.9±2.8 respectively after 20 washing.This net could provide a good personal protection against malaria vectors and could induce relatively high mortality, inhibit the blood-feeding as well as reduce the entry rates of female mosquitoes even after several washes.

  9. Wash Resistance and Bioefficacy of Alpha-cypermethrin Long Lasting Impregnated Nets (LLIN-Interceptor® against Anopheles stephensi using Tunnel Test

    Directory of Open Access Journals (Sweden)

    Hassan Vatandoost

    2013-03-01

    Full Text Available Background: The Long-lasing insecticide impregnated nets (LLINs is considered as an effective tools for malaria vector control. The aim of this study was to evaluate the residual efficacy of alpha-cypermethrin long lasting im­pregnated nets (LLIN-Interceptor® against Anopheles stephensi using tunnel test.Methods: The wash-resistance of Interceptor® nets were assessed under laboratory conditions using tunnel test. Females of An. stephensi were released into the tunnel and then they were provided blood meals from guinea pigs. Bed nets were washed according to the standard procedure up to 20 times. The bioefficacy indicators such as inhi­bition of bloodmeal from experimental animal, knockdown, irritancy rate, survival rate, entry index and mortality were calculated.Results: It induced 90–100% mortalities in the population of An. stephensi up to 15 washes. The KT50 values re­duced from 73.47 to 26.30 minutes in unwashed in comparison to one washed, respectively. The mean of mortality rate of blood-feeding inhibition and entry indexes was reached to 91.6%±2.8, 87.0±3.4 and 24.9±2.8 respectively after 20 washing.Conclusion: This net could provide a good personal protection against malaria vectors and could induce relatively high mortality, inhibit the blood-feeding as well as reduce the entry rates of female mosquitoes even after several washes.

  10. Phytochemistry and larvicidal activity of Eucalyptus camaldulensisagainst malaria vector,Anopheles stephensi

    Institute of Scientific and Technical Information of China (English)

    Sedaghat Mohamad Medhi; SaneiAli Reza; Khnavi Mahnaz; Abai Mohammad Reza; Hadjiakhoondi Abbas; MohtaramiFatemeh; VatandoostHassan

    2010-01-01

    Objective:To determine phytochemistry and larvicidal activity ofEucalyptus camaldulensis againstAnopheles stephensi.Methods:The chemical compositions of the leaf essential oils were analyzed using gas chromatography/mass spectrometry (GC/MS). The larvicidal activity of essential oils and extract of leaf were tested against 4th instar larvae of laboratory-rearedAnopheles stephensi.Results:GC/MS analyses identified the presence of28 compounds corresponding to 99.60%of the total oil. The main constituents in the leaf essential oil were1,8-cineole(69.46%), γ-Terpinene(15.10%), α-Pinene(5.47%)and Globulol(2%). The leaf extract and volatile oil exerted significant larvicidal activity withLC50 values of89.85 and397.75ppm, respectively. Clear dose-response relationships were established with the highest dose of320 ppm essential oil extract resulted almost100% mortality in the population.Conclusions:The larvicidal properties suggest that the essential oil of plant is a potential source of valuable larvicidal compounds against malaria vector and can be used as an alternative to synthetic insecticides.

  11. Comparative efficacy of neem and dimethyl phthalate (DMP)against malaria vector,Anopheles stephensi (dip-tera:culicidae)

    Institute of Scientific and Technical Information of China (English)

    HVatandoos; FRafi; AKhazani; JRafinejad; MKhoobdel; AKebriai-Zadeh; MRAbai; AAHanafi Bojd; AAAkhavan; SMAbtahi

    2008-01-01

    Malaria is one of the most important parasitic diseases in the world which is transmitted by the Anopheles mos-quitoes.There are several methods for malaria control.One of them is application of repellents on skin in ma-larious area as an intergrated vectro management measures.This study evaluated two repellents of DMP as a synthtic and locally product of neem oil as a botanical repellent against Anopheles stephensi.The modified method of K &D was used for the tests.Probing/biting rates on the shaved belly of white rabbits were coun-ted.ED50 and ED95 values were calculated by probit statistic software.Calculation of effective dose (ED50, ED90)on human volunteer and white rabbit was performed using regression line.Protection and failure time of DMP and neem oil was also determined.ED50 value of DMP and neem oil was determined as 0.0076 and 0. 159 mg/cm2 respectively on white rabit.The figures of ED90 value of DMP and neem oil was determined as 0. 046 and 1.388 mg/cm2 .DMP and neem oil showed repellency effects against An.stephensi on human volun-teers with ED50 value of 0.0037 and 0.127 mg/cm2 respectively.ED90 value of DMP was determined as 0. 032 mg/cm2 .neem oil exhibited a ED90 value of 1.066 mg/cm2 on human volunteer.The protection time of 6-7 hours for DMP and 31 minute for neem oil was determined.The failure times for DMP and Neem was 9 hours and 65 minutes rspectively on human bait.Our results exhibited that plant-based repellent is generally less effective than synthetic repellents.However,use of locally made botanical materials would be of great ad-vantages for personal protection against mosquito biting.

  12. Biting behavior of Anopheles mosquitoes in Costa Marques, Rondonia, Brazil

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    Terry A. Klein

    1991-03-01

    Full Text Available Mosquito collections were made in and near Costa Marques, Rondonia, Brazil, to determine anopheline anthropophilic/zoophilic behavior. Collections from a non-illuminated, bovine-baited trap and indoor and outdoor human-bait collections were compared. Anopheles darlingi and Anopheles deaneorum were more anthropophilic than the other anophelines collected. The remainder of the Anopheles species were collected much morefrequently in bovine-baited traps than in human-bait collections. Anopheles darlingi and An. deaneorum were more frequently collected inside houses than the other anopheline species. But, when collections were made in a house with numerous openings in the walls, there were few differences in the percentages of each species biting man indoors versus outdoors. Anopheles darlingi was the predominant mosquito collected, both inside and outside houses, and had the strongest anthropophilic feeding behavior of the anophelines present.Para determinar o comportamento antropofilico e zoofilico dos anofelinos, foram capturados mosquitos na periferia e na zona urbana de Costa Marques, Rondônia, Brasil. Foram comparadas as capturas feitas à noite, com iscas bovinas e humanas, dentro efora de casa. O Anopheles darlingi e o Anopheles deaneorumforam mais antropojilicos do que os outros anofelinos capturados. O restante das espécies anofelinas foi capturado mais freqüentemente nas iscas bovinas do que nas humanas. Anopheles darlingi e Anopheles deaneorumforam capturados dentro de casa com mais freqüência do que as outras espécies anofelinas. Porém, quando a captura foi feita em casas com muitas aberturas nas paredes houve pouca diferença nas porcentagens de cada espécie sugadora de humanos dentro efora de casa. Anopheles darlingi foi o mosquito capturado com mais freqüência, dentro e fora de casa, e apresentava maior antropofilia em relação aos outros anofelinos presentes.

  13. Green synthesis of silver nanoparticles using Sida acuta (Malvaceae) leaf extract against Culex quinquefasciatus, Anopheles stephensi, and Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Veerakumar, Kaliyan; Govindarajan, Marimuthu; Rajeswary, Mohan

    2013-12-01

    Mosquitoes act as a vector for most of the life-threatening diseases like malaria, yellow fever, dengue fever, chikungunya fever, filariasis, encephalitis, West Nile Virus infection, etc. Under the Integrated Mosquito Management, emphasis was given on the application of alternative strategies in mosquito control. The continuous application of synthetic insecticides causes development of resistance in vector species, biological magnification of toxic substances through the food chain, and adverse effects on environmental quality and nontarget organisms including human health. Application of active toxic agents from plant extracts as an alternative mosquito control strategy was available from ancient times. These are nontoxic, easily available at affordable prices, biodegradable, and show broad-spectrum target-specific activities against different species of vector mosquitoes. In the present study, the larvicidal activity of silver nanoparticles (AgNPs) synthesized using Sida acuta plant leaf extract against late third instar larvae of Culex quinquefasciatus, Anopheles stephensi, and Aedes aegypti was determined. Range of concentrations of synthesized AgNPs (10, 20, 30, 40, and 50 μg/mL) and aqueous leaf extract (50, 100, 150, 200, and 250 μg/mL) were tested against the larvae of C. quinquefasciatus, A. stephensi and A. aegypti. The synthesized AgNPs from S. acuta leaf were highly toxic than crude leaf aqueous extract in three important vector mosquito species. The results were recorded from UV-Vis spectrum, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy analysis. Larvae were exposed to varying concentrations of aqueous crude extract and synthesized AgNPs for 24 h. Considerable mortality was evident after the treatment of S. acuta for all three important vector mosquitoes. The LC50 and LC90 values of S. acuta aqueous leaf extract appeared to be most effective

  14. Study on Fungal Flora in the Midgut of the Larva and Adult of the Different Populations of the Malaria Vector Anopheles stephensi

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    L Tajedin

    2009-07-01

    Full Text Available Abstract Background: Many microorganisms in midgut of mosquito challenge with their host and also other pathogens pre­sent in midgut. The aim of this study was presence of non-pathogens microorganisms like fungal flora which may be cru­cial on interaction between vectors and pathogens."nMethods: Different populations of Anopheles stephensi were reared in insectary and objected to determine fungal flora in their midguts. The midgut paunch of mosquito adults and larvae as well as breading water and larval food sam­ples transferred on Subaru-dextrose agar, in order to detect the environment fungus."nResults: Although four fungi, Aspergillus, Rhizopus, Geotrichum and Sacharomyces were found in the food and wa­ter, but only Aspiragilus observed in the midgut of larvae. No fungus was found in the midgut of adults. This is the first report on fungal flora in the midgut of the adults and larvae of An. stephensi and possible stadial transmission of fungi from immature stages to adults."nConclusion: The midgut environment of adults is not compatible for survivorship of fungi but the larval midgut may con­tain few fungi as a host or even pathogen.

  15. Persistent Infection by Wolbachia wAlbB Has No Effect on Composition of the Gut Microbiota in Adult Female Anopheles stephensi

    Science.gov (United States)

    Chen, Shicheng; Zhao, Jiangchao; Joshi, Deepak; Xi, Zhiyong; Norman, Beth; Walker, Edward D.

    2016-01-01

    The bacteria in the midgut of Anopheles stephensi adult females from laboratory colonies were studied by sequencing the V4 region of 16S rRNA genes, with respect to three experimental factors: stable or cured Wolbachia infection; sugar or blood diet; and age. Proteobacteria and Bacteroidetes dominated the community [>90% of operational taxonomic units (OTUs)]; most taxa were in the classes Flavobacteriia, Gammaproteobacteria, and Alphaproteobacteria, and were assigned to Elizabethkingia (46.9%), Asaia (6.4%) and Pseudomonas (6.0%), or unclassified Enterobacteriaceae (37.2%). Bacterial communities were similar between Wolbachia-cured and Wolbachia-infected mosquito lines, indicating that the gut microbiota were not dysregulated in the presence of Wolbachia. The proportion of Enterobacteriaceae was higher in mosquitoes fed a blood meal compared to those provided a sugar meal. Collectively, the bacterial community had a similar structure in older Wolbachia-infected mosquitoes 8 days after the blood meal, as in younger Wolbachia-infected mosquitoes before a blood meal, except that older mosquitoes had a higher proportion of Enterobacteriaceae and lower proportion of Elizabethkingia. Consistent presence of certain predominant bacteria (Elizabethkingia, Asaia, Pseudomonas, and Enterobacteriaceae) suggests they would be useful for paratransgenesis to control malaria infection, particularly when coupled to a Wolbachia-based intervention strategy. PMID:27708633

  16. Factors affecting fungus-induced larval mortality in Anopheles gambiae and Anopheles stephensi

    NARCIS (Netherlands)

    Bukhari, S.T.; Middelman, A.; Koenraadt, C.J.M.; Takken, W.; Knols, B.G.J.

    2010-01-01

    Background Entomopathogenic fungi have shown great potential for the control of adult malaria vectors. However, their ability to control aquatic stages of anopheline vectors remains largely unexplored. Therefore, how larval characteristics (Anopheles species, age and larval density), fungus (species

  17. "Repellent Effect of Extracts and Essential Oils of Citrus limon (Rutaceae and Melissa officinalis (Labiatae Against Main Malaria Vector, Anopheles stephensi (Diptera: Culicidae"

    Directory of Open Access Journals (Sweden)

    "MA Oshaghi

    2003-10-01

    Full Text Available Repellet effect of extracts and essential oils of Citrus limon (L. Burm.F., (lemon and Melissa officinalis, (balm were evaluated against Anopheles stephensi in laboratory on animal and human and compared with synthetic repellent, N,Ndiethyl- 3-methylbenzamide (Deet as a standard. Results of statistical analysis revealed significant differences between oils and extracts (P< 0.05 against the tested species, thus oils were more effective than extracts. There was no significant difference between Deet and lemon oil, whereas the difference between lemon and melissa oils was significant. Relative efficacy of lemon oil to Deet was 0.88 whereas it was 0.71 for melissa oil. The results were found marginally superior in repellency for animals than human. Due to advantages of botanic compounds to synthetic compounds we recommend lemon essential oil as an effective alternative to Deet with potential as a means of personal protection against mosquito vectors of disease.

  18. Larvicidal, ovicidal and pupicidal activities ofGliricidia sepium (Jacq.) (Leguminosae) against the malarial vector,Anopheles stephensiListon (Culicidae:Diptera)

    Institute of Scientific and Technical Information of China (English)

    Kaliyamoorthy Krishnappa; Shanmugam Dhanasekaran; Kuppusamy Elumalai

    2012-01-01

    Objective:To investigate the potentiality of mosquitocidal activity ofGliricidia sepium(G. sepium) (Jacq.)(Leguminosae).Methods:Twenty five early third instar larvae ofAnopheles stephensi (An. stephensi) were exposed to various concentrations(50-250 ppm) and the24 hLC50 values of theG. sepium extract was determined by probit analysis.The ovicidal activity was determined againstAn. stephensi to various concentrations ranging from25-100 ppm under laboratory conditions.The eggs hatchability was assessed48 h post treatment.The pupicidal activity was determined againstAn. stephensi to various concentrations ranging from25-100 ppm.Mortality of each pupa was recorded after24 h of exposure to the extract.Results:Results pertaining to the experiment clearly revealed that ethanol extract showed significant larvicidal, ovicidal and pupicidal activity against theAn. stephensi.Larvicidal activityof ethanol extracts ofG. sepium showed maximum mortality in250 ppm concentration(96.0±2.4)%.Furthermore, theLC50 was found to be121.79 and theLC90value was recorded to be231.98 ppm.Ovicidal activity of ethanol extract was assessed by assessing the egg hatchability.Highest concentration of both solvent extracts exhibited100% ovicidal activity.Similarly, pupae exposed to different concentrations of ethanol extract were found dead with58.10% adult emergence when it was treated with25 ppm concentration.Similarly,18.36(n=30;61.20%);21.28(70.93) and27.33(91.10) pupal mortality was recorded from the experimental pupae treated with50,75 and100 ppm concentration of extracts. Three fractions have been tested for their larvicidal activity of which theFraction3 showed the LC50 andLC90 values of23.23 and40.39 ppm.With regard to the ovicidal effect fraction3 showed highest ovicidal activities than the other two fractions.Furthermore, there were no hatchability was recorded above50 ppm(100% egg mortality) in the experimental group.Statistically significant pupicidal activity was recorded from75 ppm

  19. SUSCEPTIBILITY TESTS OF ANOPHELES STEPHENSI WITH SOME CHLORINE, PHOSPHORUS, CARBAMATE AND PYRETILROID INSECTICICDES IN SOUTH OF IRAN

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    M.Iranpour

    1993-12-01

    Full Text Available Susceptibility tests were carried out on Anopheles stephensi with D.D.T(4%, dieldrin (4%, malathion(5%, propoxus (0.1%, primphos-methyl (O.lmg/cm2, lambda-cyhalothrin (0.1%, permethrin (0.25% and deltamethrin (0.025% during 1990-94 in Minab county, soutern Iran, using W.H.O standard method. Results showed that An. stephensi was susceptible to malathion, propoxur, primphos - methyl, lambda- cyhalothrin permethrin and deltamethrin, also LT5O was 5,19.5, less than 1.less than 1,3 and less than 1 minute, respectively. Results indicated that An.stephensi was still resistant to D.D.T and dieldrin but susceptibility level has increased. Mortality rate was 36.1 and 80.6 when the species was exposed to D.D.T and dieldrin impregnated papers for 60 minutes, respectively.

  20. Highly evolvable malaria vectors : the genomes of 16 Anopheles mosquitoes

    OpenAIRE

    Neafsey, Daniel E; Waterhouse, Robert M.; Abai, Mohammad R.; Aganezov, Sergey S.; Alekseyev, Max A.; Allen, James E.; Amon, James; Arcà, Bruno; Arensburger, Peter; Artemov, Gleb; Assour, Lauren A.; Basseri, Hamidreza; Berlin, Aaron; Birren, Bruce W.; Blandin, Stephanie A.

    2015-01-01

    Variation in vectorial capacity for human malaria among Anopheles mosquito species is determined by many factors, including behavior, immunity, and life history. To investigate the genomic basis of vectorial capacity and explore new avenues for vector control, we sequenced the genomes of 16 anopheline mosquito species from diverse locations spanning similar to 100 million years of evolution. Comparative analyses show faster rates of gene gain and loss, elevated gene shuffling on the X chromos...

  1. Mosquitocidal and antibacterial activity of green-synthesized silver nanoparticles from Aloe vera extracts: towards an effective tool against the malaria vector Anopheles stephensi?

    Science.gov (United States)

    Dinesh, Devakumar; Murugan, Kadarkarai; Madhiyazhagan, Pari; Panneerselvam, Chellasamy; Kumar, Palanisamy Mahesh; Nicoletti, Marcello; Jiang, Wei; Benelli, Giovanni; Chandramohan, Balamurugan; Suresh, Udaiyan

    2015-04-01

    Mosquitoes represent an important threat for lives of millions of people worldwide, acting as vectors for devastating pathogens, such as malaria, yellow fever, dengue, and West Nile. In addition, pathogens and parasites polluting water also constitute a severe plague for populations of developing countries. Here, we investigated the mosquitocidal and antibacterial properties of Aloe vera leaf extract and silver nanoparticles synthesized using A. vera extract. Mosquitocidal properties were assessed in laboratory against larvae (I-IV instar) and pupae of the malaria vector Anopheles stephensi. Green-synthesized silver nanoparticles were tested against An. stephensi also in field conditions. Antibacterial properties of nanoparticles were evaluated against Bacillus subtilis, Klebsiella pneumoniae, and Salmonella typhi using the agar disk diffusion and minimum inhibitory concentration protocol. The synthesized silver nanoparticles were characterized by UV-vis spectrum, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). In laboratory conditions, the A. vera extract was toxic against An. stephensi larvae and pupae, even at low dosages. LC50 were 48.79 ppm (I instar), 59.09 ppm (II instar), 70.88 ppm (III instar), 83.58 ppm (IV instar), and 152.55 ppm (pupae). Green-synthesized silver nanoparticles were highly toxic against An. stephensi. LC50 were 3.825 ppm (I instar), 4.119 ppm (II instar), 4.982 ppm (III instar), 5.711 ppm (IV instar), and 6.113 ppm (pupae). In field conditions, the application of A. vera-synthesized silver nanoparticles (10 × LC50) leads to An. stephensi larval reduction of 74.5, 86.6, and 97.7%, after 24, 48, and 72 h, respectively. Nanoparticles also showed antibacterial properties, and the maximum concentration tested (150 mg/L) evoked an inhibition zone wider than 80 mm in all tested bacterium species. This study adds knowledge about the use of green synthesis of nanoparticles in

  2. Differential expression of glutathione s-transferase enzyme in different life stages of various insecticide-resistant strains of Anopheles stephensi: A malaria vector

    Directory of Open Access Journals (Sweden)

    D. Sanil

    2014-04-01

    Full Text Available Background & objectives: Interest in insect glutathione s-transferases (GSTs has primarily focused on their role in insecticide resistance. These play an important role in biotransformation and detoxification of many different xenobiotic and endogenous substances including insecticides. The GST activity among 10 laboratory selected insecticide resistant and susceptible/control strains of Anopheles stephensi was compared using the substrates 1-chloro-2,4-dinitrobenzene (CDNB. The difference in the GST activities of different life stages of diverse insecticide resistant strains was compared and presented. Methods: About 100 larvae, pupae, adult males, adult females and eggs (100 μg in total weight were collected and used for the experiment. The extracts were prepared from each of the insecticide-resistant strains and control. Protein contents of the enzyme homogenate and GST activities were determined. Results: Deltamethrin and cyfluthrin-resistant strains of An. stephensi showed significantly higher GST activity. Larvae and pupae of DDT-resistant strain showed peak GST activity followed by the propoxur-resistant strain. On contrary, the GST activity was found in reduced quantity in alphamethrin, bifenthrin, carbofuran and chloropyrifos resistant strains. Adults of either sexes showed higher GST activity in mosquito strain resistant to organophosphate group of insecticides namely, temephos and chloropyrifos. Interpretation & conclusion: The GST activity was closely associated with almost all of the insecticides used in the study, strengthening the fact that one of the mechanisms associated with resistance includes an increase of GST activity. This comparative data on GST activity in An. stephensi can be useful database to identify possible underlying mechanisms governing insecticide-resistance by GSTs.

  3. Larvicidal activity of silver nanoparticles synthesized using Pergularia daemia plant latex against Aedes aegypti and Anopheles stephensi and nontarget fish Poecillia reticulata.

    Science.gov (United States)

    Patil, Chandrashekhar D; Borase, Hemant P; Patil, Satish V; Salunkhe, Rahul B; Salunke, Bipinchandra K

    2012-08-01

    In present study, the bioactivity of latex-producing plant Pergularia daemia as well as synthesized silver nanoparticles (AgNPs) against the larval instars of Aedes aegypti and Anopheles stephensi mosquito larvae was determined. The range of concentrations of plant latex (1,000, 500, 250, 125, 62.25, and 31.25 ppm) and AgNPs (10, 5, 2.5, 1.25, 0.625, and 0.3125 ppm) were prepared. The LC(50) and LC(90) values for first, second, third, and fourth instars of synthesized AgNPs-treated first, second, third, and fourth instars of A. aegypti (LC(50) = 4.39, 5.12, 5.66, 6.18; LC(90) = 9.90, 11.13, 12.40, 12.95 ppm) and A. stephensi (LC(50) = 4.41, 5.35, 5.91, 6.47; LC(90) = 10.10, 12.04, 13.05, 14.08 ppm) were found many fold lower than crude latex-treated A. aegypti (LC(50) = 55.13, 58.81, 75.66, 94.31; LC(90) = 113.00, 118.25, 156.95, 175.71 ppm) and A. stephensi (LC(50) = 81.47, 92.09, 96.07, 101.31; LC(90) = 159.51, 175.97, 180.67, 190.42 ppm). The AgNPs did not exhibit any noticeable effects on Poecillia reticulata after either 24 or 48 h of exposure at their LC(50) and LC(90) values against fourth-instar larvae of A. aegypti and A. stephensi. The UV-visible analysis shows absorbance for AgNPs at 520 nm. TEM reveals spherical shape of synthesized AgNPs. Particle size analysis revealed that the size of particles ranges from 44 to 255 nm with average size of 123.50 nm. AgNPs were clearly negatively charged (zeta potential -27.4 mV). This is the first report on mosquito larvicidal activity P. daemia-synthesized AgNPs.

  4. Adult emergence inhibition and adulticidal activities of medicinal plant extracts againstAnopheles stephensiListon

    Institute of Scientific and Technical Information of China (English)

    AbdulAbduzZahir; AbdulAbdulRahuman; AsokanBa=gavan; GandhiElango; Chinnaperumal Kamaraj

    2010-01-01

    Objective:To determine the adult emergence inhibition (EI) and adulticidal activities of hexane, chloroform, ethyl acetate, and acetone leaves extracts of Anisomeles malabarica (A. malabarica), Euphorbia hirta (E. hirta), Ocimum basilicum (O. basilicum), Ricinus communis (R. communis), Solanum trilobatum (S. trilobatum), Tridax procumbens (T. procumbens)and seeds ofGloriosa superba (G. superba) againstAnopheles stephensi (An. stephensi).Methods: The EI and adulticidal trials were carried out according to World Health Organization (WHO) procedures with slight modifications. The extracts were diluted in dimethyl sulphoxide in order to prepare a serial dilution of test dosages (15.625, 31.25, 62.5, 125, 250, 500 and1 000μg/mL). Five duplicate trials were carried out for every sample concentration, and for each trial a negative control was included and the mortality was determined after24 h of exposure.Results: The highestEI activity was found in ethyl acetate extracts ofA. malabarica, chloroform extracts ofO. basilicum, S.trilobatum, acetone of extract ofR. communis, T. procumbens, and seed extract ofG. superba withEI50 values143.12, 119.82, 157.87, 139.39, 111.19, and134.85 μg/mL, and the effective adulticidal activity was observed in chloroform, acetone extracts ofG. superba, T. procumbens, R. communis, S.trilobatum and ethyl acetate extract ofO. basilicum with LD50 values120.17, 108.77, 127.22, 163.11, 118.27, and93.02μg/mL, respectively. Chi-square value was significant atP<0.05 level.Conclusions: These results should encourage further efforts to investigate the compounds that might possess good EI and adulticidal properties when isolated in pure form.

  5. Observations on sporozoite detection in naturally infected sibling species of the Anopheles culicifacies complex and variant of Anopheles stephensi in India

    Indian Academy of Sciences (India)

    Susanta Kumar Ghosh; Satyanarayan Tiwari; Kamaraju Raghavendra; Tiruchinapalli Sundaraj; Aditya Prasad Dash

    2008-09-01

    Sporozoites were detected in naturally infected sibling species of the primary rural vector Anopheles culicifacies complex in two primary health centres (PHCs) and a variant of the urban vector Anopheles stephensi in Mangalore city, Karnataka, south India while carrying out malaria outbreak investigations from 1998–2006. Sibling species of An. culicifacies were identified based on the banding patterns on ovarian polytene chromosomes, and variants of An. stephensi were identified based on the number of ridges on the egg floats. Sporozoites were detected in the salivary glands by the dissection method. Of the total 334 salivary glands of An. culicifacies dissected, 17 (5.08%) were found to be positive for sporozoites. Of the 17 positive samples, 11 were suitable for sibling species analysis; 10 were species A (an efficient vector) and 1 was species B (a poor vector). Out of 46 An. stephensi dissected, one was sporozoite positive and belonged to the type form (an efficient vector). In malaria epidemiology this observation is useful for planning an effective vector control programme, because each sibling species/variant differs in host specificity, susceptibility to malarial parasites, breeding habitats and response to insecticides.

  6. Lectin-carbohydrate recognition mechanism of Plasmodium berghei in the midgut of malaria vector Anopheles stephensi using quantum dot as a new approach.

    Science.gov (United States)

    Basseri, Hamid R; Javazm, Mahdi Salari; Farivar, Leila; Abai, Mohammad R

    2016-04-01

    Potential targets of Plasmodium ookinetes at the mosquito midgut walls were investigated in relation to interfering malarial transmission. In this study, the essential application of Quantum Dots (QDs) was used to examine the interaction between Plasmodium berghei ookinetes and the Anopheles stephensi midgut, based on lectin-carbohydrate recognition. Two significant lectins were utilized to determine this interaction. Two QDs, cadmium telluride (CdTe)/CdS and cadmium selenide (CdSe)/CdS, were employed in staining Plasmodium ookinete to study its interaction in the midgut of the mosquito vector in vivo. Concurrently, two lectins, wheat germ agglutinin (WGA) and concanavalin A (Con A), were inadvertently exploited to mask lectin binding sites between ookinetes and mosquito midgut cells. The numbers of ookinetes in both lumen and epithelial cells were eventually counted, following adequate preparation of wax sections extracted from whole midgut, and subsequent examination using a differential interference contrast a fluorescence microscopic technique. Interestingly, we detected that neither of the QDs mutated ookinete invasion into the midgut cells of the investigated mosquitoes. QD staining of ookinetes remained permanent despite the effective embedding procedure. The massive binding potency of ookinetes to midgut cells of the cross-examined mosquitoes undoubtedly revealed that Con A did not interrupt ookinete penetration into the midgut wall. In contrast, WGA inhibited ookinete invasion into the midgut cells. The results proved that QD nanoparticles are biocompatible, non-toxic to P. berghei and stable to photobleaching. The QDs staining, which was successfully implemented for ookinete labelling, is a simple and effective tool which plays a crucial role in bioimaging including the study of parasite-vector interactions. PMID:26772447

  7. Lectin-carbohydrate recognition mechanism of Plasmodium berghei in the midgut of malaria vector Anopheles stephensi using quantum dot as a new approach.

    Science.gov (United States)

    Basseri, Hamid R; Javazm, Mahdi Salari; Farivar, Leila; Abai, Mohammad R

    2016-04-01

    Potential targets of Plasmodium ookinetes at the mosquito midgut walls were investigated in relation to interfering malarial transmission. In this study, the essential application of Quantum Dots (QDs) was used to examine the interaction between Plasmodium berghei ookinetes and the Anopheles stephensi midgut, based on lectin-carbohydrate recognition. Two significant lectins were utilized to determine this interaction. Two QDs, cadmium telluride (CdTe)/CdS and cadmium selenide (CdSe)/CdS, were employed in staining Plasmodium ookinete to study its interaction in the midgut of the mosquito vector in vivo. Concurrently, two lectins, wheat germ agglutinin (WGA) and concanavalin A (Con A), were inadvertently exploited to mask lectin binding sites between ookinetes and mosquito midgut cells. The numbers of ookinetes in both lumen and epithelial cells were eventually counted, following adequate preparation of wax sections extracted from whole midgut, and subsequent examination using a differential interference contrast a fluorescence microscopic technique. Interestingly, we detected that neither of the QDs mutated ookinete invasion into the midgut cells of the investigated mosquitoes. QD staining of ookinetes remained permanent despite the effective embedding procedure. The massive binding potency of ookinetes to midgut cells of the cross-examined mosquitoes undoubtedly revealed that Con A did not interrupt ookinete penetration into the midgut wall. In contrast, WGA inhibited ookinete invasion into the midgut cells. The results proved that QD nanoparticles are biocompatible, non-toxic to P. berghei and stable to photobleaching. The QDs staining, which was successfully implemented for ookinete labelling, is a simple and effective tool which plays a crucial role in bioimaging including the study of parasite-vector interactions.

  8. Transmission blocking activity of a standardized neem (Azadirachta indica seed extract on the rodent malaria parasite Plasmodium berghei in its vector Anopheles stephensi

    Directory of Open Access Journals (Sweden)

    Esposito Fulvio

    2010-03-01

    Full Text Available Abstract Background The wide use of gametocytocidal artemisinin-based combination therapy (ACT lead to a reduction of Plasmodium falciparum transmission in several African endemic settings. An increased impact on malaria burden may be achieved through the development of improved transmission-blocking formulations, including molecules complementing the gametocytocidal effects of artemisinin derivatives and/or acting on Plasmodium stages developing in the vector. Azadirachtin, a limonoid (tetranortriterpenoid abundant in neem (Azadirachta indica, Meliaceae seeds, is a promising candidate, inhibiting Plasmodium exflagellation in vitro at low concentrations. This work aimed at assessing the transmission-blocking potential of NeemAzal®, an azadirachtin-enriched extract of neem seeds, using the rodent malaria in vivo model Plasmodium berghei/Anopheles stephensi. Methods Anopheles stephensi females were offered a blood-meal on P. berghei infected, gametocytaemic BALB/c mice, treated intraperitoneally with NeemAzal, one hour before feeding. The transmission-blocking activity of the product was evaluated by assessing oocyst prevalence, oocyst density and capacity to infect healthy mice. To characterize the anti-plasmodial effects of NeemAzal® on early midgut stages, i.e. zygotes and ookinetes, Giemsa-stained mosquito midgut smears were examined. Results NeemAzal® completely blocked P. berghei development in the vector, at an azadirachtin dose of 50 mg/kg mouse body weight. The totally 138 examined, treated mosquitoes (three experimental replications did not reveal any oocyst and none of the healthy mice exposed to their bites developed parasitaemia. The examination of midgut content smears revealed a reduced number of zygotes and post-zygotic forms and the absence of mature ookinetes in treated mosquitoes. Post-zygotic forms showed several morphological alterations, compatible with the hypothesis of an azadirachtin interference with the functionality

  9. Anopheles (Anopheles) petragnani Del Vecchio 1939-a new mosquito species for Germany.

    Science.gov (United States)

    Becker, Norbert; Pfitzner, Wolf Peter; Czajka, Christina; Kaiser, Achim; Weitzel, Thomas

    2016-07-01

    The so far known species of the Anopheles Claviger Complex, Anopheles claviger s.s. and Anopheles petragnani, can only be distinguished by partial overlapping characteristics of immature stages and by nucleotide sequence variation of the genomic ribosomal DNA (rDNA) internal transcribed spacer 2 (ITS2) region. The known distribution of An. petragnani is so far restricted to the western Mediterranean region, whereas An. claviger s.s. occurs across most of Europe, up to the Middle East and North Africa. In our study, we investigated the larval mosquito fauna in rock pools of the Murg valley (Black Forest, Germany) once a month from April to December 2015.Among other species, larvae belonging to the Anopheles Claviger Complex were found. The fourth instar larvae were morphologically identified by chaetotaxy of the head and abdomen. The results were confirmed by a multiplex PCR and additional sequencing of the amplificates.Of the 1289 collected larvae from the rock pools, seven belonged to the Anopheles Claviger Complex. Five individuals were determined morphologically as An. petragnani and two as An. claviger s.s. The associated mosquito fauna comprised of Aedes japonicus japonicus (548 individuals), Culex pipiens s.l. and Culex torrentium (493 individuals) and Culex hortensis (241 individuals).This is the first record of An. petragnani north of the Alps. Further studies will reveal whether this is an isolated population of An. petragnani and if the investigated rock pool breeding sites represent typical habitats of this species in temperate regions in Central Europe.

  10. Baseline Susceptibility of Different Geographical Strains of Anopheles stephensi (Diptera: Culicidae to Temephos in Malarious Areas of Iran

    Directory of Open Access Journals (Sweden)

    Aboozar Soltani

    2013-03-01

    Full Text Available Background: Malaria still remains a public health problem in Iran. There are different vector control interventions such as insecticide spraying. The present study was carried out to determine the susceptibility status of Anopheles stephensi larvae to temephos as a national plan for monitoring and mapping of insecticide resistanceMethods: Eight different localities in two main malarious provinces were determined as field collecting sites. Mos­quitoes were collected from the field and reared in an insectray. Susceptibility assays were carried out according to the WHO method. The laboratory reared susceptible Beech-Lab strain was used for comparison. Data were analyzed using Probit analysis to determine LC50 and LC90 values.Results: Susceptibility of An. stephensi to temephos indicated that the LC50 ranged from 0.0022 mg/l to 0.0141 mg/l. Although all field strains were susceptible to temephos, considerable variations in temephos resistance ratios of field strains were noticed from all the localities studied in comparison with the susceptible strain. A low level of resistance ratio was noticed in An. stephensi populations except for the Chabahar strain (RR= 4.27 fold. All field-collected An. stephensi populations exhibited homogeneity to the larvicide except for Bandar Abbas and Hormoodar village strains (P> 0.05%.Conclusion: Due to intensive use of temephos in the neighboring countries and occurrence of resistant to this insec­ticide in the main malaria vector in the region, insecticide resistance gene may evolve in the populations of An. stephensi. If temephos be applied as a larvicide it should be used judiciously for resistance management, as rotation strategy

  11. In depth annotation of the Anopheles gambiae mosquito midgut transcriptome

    OpenAIRE

    Padrón, Alejandro; Molina-Cruz, Alvaro; Quinones, Mariam; Ribeiro, José MC; Ramphul, Urvashi; Rodrigues, Janneth; Shen, Kui; Haile, Ashley; Ramirez, José Luis; Barillas-Mury, Carolina

    2014-01-01

    Background Genome sequencing of Anopheles gambiae was completed more than ten years ago and has accelerated research on malaria transmission. However, annotation needs to be refined and verified experimentally, as most predicted transcripts have been identified by comparative analysis with genomes from other species. The mosquito midgut—the first organ to interact with Plasmodium parasites—mounts effective antiplasmodial responses that limit parasite survival and disease transmission. High-th...

  12. Seaweed-synthesized silver nanoparticles: an eco-friendly tool in the fight against Plasmodium falciparum and its vector Anopheles stephensi?

    Science.gov (United States)

    Murugan, Kadarkarai; Samidoss, Christina Mary; Panneerselvam, Chellasamy; Higuchi, Akon; Roni, Mathath; Suresh, Udaiyan; Chandramohan, Balamurugan; Subramaniam, Jayapal; Madhiyazhagan, Pari; Dinesh, Devakumar; Rajaganesh, Rajapandian; Alarfaj, Abdullah A; Nicoletti, Marcello; Kumar, Suresh; Wei, Hui; Canale, Angelo; Mehlhorn, Heinz; Benelli, Giovanni

    2015-11-01

    Malaria, the most widespread mosquito-borne disease, affects 350-500 million people each year. Eco-friendly control tools against malaria vectors are urgently needed. This research proposed a novel method of plant-mediated synthesis of silver nanoparticles (AgNP) using a cheap seaweed extract of Ulva lactuca, acting as a reducing and capping agent. AgNP were characterized by UV-vis spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The U. lactuca extract and the green-synthesized AgNP were tested against larvae and pupae of the malaria vector Anopheles stephensi. In mosquitocidal assays, LC50 values of U. lactuca extract against A. stephensi larvae and pupae were 18.365 ppm (I instar), 23.948 ppm (II), 29.701 ppm (III), 37.517 ppm (IV), and 43.012 ppm (pupae). LC50 values of AgNP against A. stephensi were 2.111 ppm (I), 3.090 ppm (II), 4.629 ppm (III), 5.261 ppm (IV), and 6.860 ppm (pupae). Smoke toxicity experiments conducted against mosquito adults showed that U. lactuca coils evoked mortality rates comparable to the permethrin-based positive control (66, 51, and 41%, respectively). Furthermore, the antiplasmodial activity of U. lactuca extract and U. lactuca-synthesized AgNP was evaluated against CQ-resistant (CQ-r) and CQ-sensitive (CQ-s) strains of Plasmodium falciparum. Fifty percent inhibitory concentration (IC50) values of U. lactuca were 57.26 μg/ml (CQ-s) and 66.36 μg/ml (CQ-r); U. lactuca-synthesized AgNP IC50 values were 76.33 μg/ml (CQ-s) and 79.13 μg/ml (CQ-r). Overall, our results highlighted out that U. lactuca-synthesized AgNP may be employed to develop newer and safer agents for malaria control.

  13. In vitro larvicidal potential against Anopheles stephensi and antioxidative enzyme activities of Ginkgo biloba, Stevia rebaudiana and Parthenium hysterophorous

    Institute of Scientific and Technical Information of China (English)

    Nisar Ahmad; Hina Fazal; Bilal H Abbasi; Mazhar Iqbal

    2011-01-01

    Objective: To investigate in vitro larvicidal and antioxidant enzymes potential of the medicinal plants Ginkgo biloba (G. biloba), Stevia rebaudiana (S. rebaudiana) and Parthenium hysterophorous (P. hysterophorous) against Anopheles stephensi (An. stephensi) 4th instars larvae. Methods:For evaluation of larvicidal potential, the ethanolic, methanolic and dichloromethane leaves extracts of three different plants were used in dose-dependent experiments in two media, while the antioxidant enzymes activities were investigated using four different methods viz., superoxide dismutase, peroxidase, ascorbate and catalase. Results:An. stephensi has developed resistance to various synthetic insecticides, making its control increasingly difficult. The comparative performance of ethanolic extracts (65%-90%) was found better than the methanolic extract (70%-87%) and dichloromethane extract (60%-70%). Among the three plants extracts tested in two media, S. rebaudiana exhibited higher larvicidal activity with LC50 (24 h) in methanolic extract than P. hysterophorous and G. biloba. G. biloba and P. hysterophorous exhibited the strongest antioxidative enzymes activity and S. rebaudiana were less active and no significant difference was observed. Conclusions:These three plants exhibit larvicidal potential and can be further used for vector control alternative to synthetic insecticide due to eco-friendly and diseases control, furthermore these plant species have potent antioxidative enzyme activities, therefore, making them strong natural candidate particularly for diseases which are caused due to free radicals.

  14. Studies on larvicidal and pupicidal activity of Leucas aspera Willd. (Lamiaceae) and bacterial insecticide, Bacillus sphaericus, against malarial vector, Anopheles stephensi Liston (Diptera: Culicidae)

    Science.gov (United States)

    The efficacy of whole plant ethanolic extracts of Leucas aspera and of Bacillus sphaericus was determined for larvae and pupae of Anopheles stephensi. When larvae were exposed to one of five concentrations of plant extract (6%, 8%, 10%, 12%, and 14%) for 24 h, mortality in 4th instars ranged from 1...

  15. Organization of olfactory centres in the malaria mosquito Anopheles gambiae

    Science.gov (United States)

    Riabinina, Olena; Task, Darya; Marr, Elizabeth; Lin, Chun-Chieh; Alford, Robert; O'Brochta, David A.; Potter, Christopher J.

    2016-01-01

    Mosquitoes are vectors for multiple infectious human diseases and use a variety of sensory cues (olfactory, temperature, humidity and visual) to locate a human host. A comprehensive understanding of the circuitry underlying sensory signalling in the mosquito brain is lacking. Here we used the Q-system of binary gene expression to develop transgenic lines of Anopheles gambiae in which olfactory receptor neurons expressing the odorant receptor co-receptor (Orco) gene are labelled with GFP. These neurons project from the antennae and maxillary palps to the antennal lobe (AL) and from the labella on the proboscis to the suboesophageal zone (SEZ), suggesting integration of olfactory and gustatory signals occurs in this brain region. We present detailed anatomical maps of olfactory innervations in the AL and the SEZ, identifying glomeruli that may respond to human body odours or carbon dioxide. Our results pave the way for anatomical and functional neurogenetic studies of sensory processing in mosquitoes. PMID:27694947

  16. First record of the Asian malaria vector Anopheles stephensi and its possible role in the resurgence of malaria in Djibouti, Horn of Africa.

    Science.gov (United States)

    Faulde, Michael K; Rueda, Leopoldo M; Khaireh, Bouh A

    2014-11-01

    Anopheles stephensi is an important vector of urban malaria in India and the Persian Gulf area. Its previously known geographical range includes southern Asia and the Arab Peninsula. For the first time, we report A. stephensi from the African continent, based on collections made in Djibouti, on the Horn of Africa, where this species' occurrence was linked to an unusual urban outbreak of Plasmodium falciparum malaria, with 1228 cases reported from February to May 2013, and a second, more severe epidemic that emerged in November 2013 and resulted in 2017 reported malaria cases between January and February 2014. Anopheles stephensi was initially identified using morphological identification keys, followed by sequencing of the Barcode cytochrome c-oxidase I (COI) gene and the rDNA second internal transcribed spacer (ITS2). Positive tests for P. falciparum circumsporozoite antigen in two of six female A. stephensi trapped in homes of malaria patients in March 2013 are evidence that autochthonous urban malaria transmission by A. stephensi has occurred. Concurrent with the second malaria outbreak, P. falciparum-positive A. stephensi females were detected in Djibouti City starting in November 2013. In sub-Saharan Africa, newly present A. stephensi may pose a significant future health threat because of this species' high susceptibility to P. falciparum infection and its tolerance of urban habitats. This may lead to increased malaria outbreaks in African cities. Rapid interruption of the urban malaria transmission cycle, based on integrated vector surveillance and control programs aimed at the complete eradication of A. stephensi from the African continent, is strongly recommended. PMID:25004439

  17. Green-synthesised nanoparticles from Melia azedarach seeds and the cyclopoid crustacean Cyclops vernalis: an eco-friendly route to control the malaria vector Anopheles stephensi?

    Science.gov (United States)

    Anbu, Priya; Murugan, Kadarkarai; Madhiyazhagan, Pari; Dinesh, Devakumar; Subramaniam, Jayapal; Panneerselvam, Chellasamy; Suresh, Udaiyan; Alarfaj, Abdullah A; Munusamy, Murugan A; Higuchi, Akon; Hwang, Jiang-Shiou; Kumar, Suresh; Nicoletti, Marcello; Benelli, Giovanni

    2016-09-01

    The impact of green-synthesised mosquitocidal nanoparticles on non-target aquatic predators is poorly studied. In this research, we proposed a single-step method to synthesise silver nanoparticles (Ag NP) using the seed extract of Melia azedarach. Ag NP were characterised using a variety of biophysical methods, including UV-vis spectrophotometry, scanning electron microscopy, energy-dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy. In laboratory assays on Anopheles stephensi, Ag NP showed LC50 ranging from 2.897 (I instar larvae) to 14.548 ppm (pupae). In the field, the application of Ag NP (10 × LC50) lead to complete elimination of larval populations after 72 h. The application of Ag NP in the aquatic environment did not show negative adverse effects on predatory efficiency of the mosquito natural enemy Cyclops vernalis. Overall, this study highlights the concrete possibility to employ M. azedarach-synthesised Ag NP on young instars of malaria vectors.

  18. Inhibition of Anopheles gambiae odorant receptor function by mosquito repellents.

    Science.gov (United States)

    Tsitoura, Panagiota; Koussis, Konstantinos; Iatrou, Kostas

    2015-03-20

    The identification of molecular targets of insect repellents has been a challenging task, with their effects on odorant receptors (ORs) remaining a debatable issue. Here, we describe a study on the effects of selected mosquito repellents, including the widely used repellent N,N-diethyl-meta-toluamide (DEET), on the function of specific ORs of the African malaria vector Anopheles gambiae. This study, which has been based on quantitative measurements of a Ca(2+)-activated photoprotein biosensor of recombinant OR function in an insect cell-based expression platform and a sequential compound addition protocol, revealed that heteromeric OR (ORx/Orco) function was susceptible to strong inhibition by all tested mosquito repellents except DEET. Moreover, our results demonstrated that the observed inhibition was due to efficient blocking of Orco (olfactory receptor coreceptor) function. This mechanism of repellent action, which is reported for the first time, is distinct from the mode of action of other characterized insect repellents including DEET. PMID:25657000

  19. /sup 14/C-labelled propoxur metabolic studies on Anopheles Stephensi from the south coast of Iran

    Energy Technology Data Exchange (ETDEWEB)

    Hossaini, M.A.; Manouchehri, A.V.; Zareh, Z. (Atomic Energy Organization of Iran, Teheran. Nuclear Research Centre)

    1984-08-01

    /sup 14/C-propoxur (Baygonsub(circled R)) was synthesized through the reaction of o-isopropoxyphenol with methyl isocyanate-/sup 14/C. The product was isolated chromatographically on Florisil and crystallized from carbon tetrachloride. The purity and structure were confirmed using infrared spectra, melting point, co-chromatography of Florisil column, and silica-gel G thin-layer chromatography. The purity was found to be at least 99%. The rate of absorption and other characteristics of /sup 14/C-propoxur resistance in Anopheles Stephensi from the south coast of Iran was investigated. The mortality of strain adults was 100% after a one hour exposure when 1 ppm /sup 14/C-propoxur was used. Moreover, the mortality was not changed when a lower concentration (5 ppm) was used. On the other hand, the absorbance of /sup 14/C-propoxur in several strains of A. Stephensi has been determined. The identity and TLC characteristics of products formed after 1 and 2 hours exposure, resp., to /sup 14/C-propoxur have also been investigated. 5 refs.

  20. Residual Effects of Deltamthrin WG 25% as a New Formulationon Different Surfaces against Anopheles stephensi, inSoutheastern Iran

    Directory of Open Access Journals (Sweden)

    A Raeisi

    2010-06-01

    Full Text Available Background: Indoor residual spraying (IRS is functioned as national interventions against malaria in southeastern foci of Iran and deltamethrin WP one of the insecticides have been used since past decade. In this study, the residual activity of the wettable granule (WG was studied on different surfaces in hut scale trial against Anopheles stephensi  in Iranshahr district, southeastern Iran.Methods: Three dosages of 25, 40 and 50 mg a.i./m2 of deltamethrin WG 25% formulation were applied on plaster, cement, mud, and wooden surfaces using Hudson® X-pert compression sprayer having 10 litters capacity.Results: The residual effects of deltamethrin WG 25% on different surfaces was assessed based on reduction of mortality An. stepehnsi from 100% to about 70%. At 25, 40 and 50 mg a.i./m2 the WG formulation of deltamethrin had a bioefficacy for about 2, 3 and 4 months respectively.Conclusion: There was an expectable fluctuation in mortality of An. stephensi at different sprayed surfaces as well as dosages. The proposed 50 mg/m2 WG is the longest activity for up to 4 months which needs to be applied for two spraying cycles per year at the climatically condition of southwestern Iran.

  1. Residual Effects of Deltamthrin WG 25% as a New Formulationon Different Surfaces against Anopheles stephensi, inSoutheastern Iran

    Directory of Open Access Journals (Sweden)

    A Raeisi

    2010-06-01

    Full Text Available "n "nBackground: Indoor residual spraying (IRS is functioned as national interventions against malaria in southeastern foci of Iran and deltamethrin WP one of the insecticides have been used since past decade. In this study, the residual activity of the wettable granule (WG was studied on different surfaces in hut scale trial against Anopheles stephensi  in Iranshahr district, southeastern Iran. "n "n "nMethods: Three dosages of 25, 40 and 50 mg a.i./m2 of deltamethrin WG 25% formulation were applied on plaster, cement, mud, and wooden surfaces using Hudson® X-pert compression sprayer having 10 litters capacity. "n "nResults: The residual effects of deltamethrin WG 25% on different surfaces was assessed based on reduction of mortality An. stepehnsi from 100% to about 70%. At 25, 40 and 50 mg a.i./m2 the WG formulation of deltamethrin had a bioefficacy for about 2, 3 and 4 months respectively. "nConclusion: There was an expectable fluctuation in mortality of An. stephensi at different sprayed surfaces as well as dosages. The proposed 50 mg/m2 WG is the longest activity for up to 4 months which needs to be applied for two spraying cycles per year at the climatically condition of southwestern Iran.

  2. COMPARATIVE TOXICITIES OF FOUR WHO-RECOMMENDED LARVICIDES AGAINST LAB STRAIN OF ANOPHELES STEPHENSI IN IRAN

    OpenAIRE

    H. Vatandoost; V. Moinvaziri

    1999-01-01

    Investigation on the current response of An.stephensi larvae to four WHO recommended larvicides, i.e. Malathion, temephos, chlorpyrifos and fenitrothion, were carried out in the laboratory in 1999. Diagnostic concentrations of pesticides only yielded 100% mortality with malathion. In contrast, levels of susceptibility to temphos, chlorpyrifos (0.025 mg/l) and temephos (0.625 mg/l) killed 72%, 90% and 87% of the population of An. Stephensi, respectively. At the LC50 level the efficacies of chl...

  3. Larvicidal Activity of Essential Oils of Apiaceae Plants Against Malaria Vector, Anopheles Stephensi

    Directory of Open Access Journals (Sweden)

    Y Salim Abadi

    2011-12-01

    Full Text Available Background: Plant extracts and oils may act as alternatives to conventional pesticides for malaria vector control. The aim of this study was to evaluate the larvicidal activity of essential oils of three plants of Apiaceae family against Anophe­les stephensi, the main malaria vector in Iran. Methods: Essential oils from Heracleum persicum, Foeniculum vulgare and Coriandrum sativum seeds were hydro distil­lated, then their larvicidal activity were evaluated against laboratory-reared larvae of An. stephensi according to stan­dard method of WHO. After susceptibility test, results were analysis using Probit program.Results: Essential oils were separated from H. persicum, F. vulgare and C. sativum plants and their larvicidal activi­ties were tested. Result of this study showed that F. vulgare oil was the most effective against An. stephensi with LC50 and LC90 values of 20.10 and 44.51 ppm, respectively.Conclusion: All three plants essential oil can serve as a natural larvicide against An. stephensi. F. vulgare oil exhib­ited more larvicidal properties.

  4. Malaria infection does not affect the sensitivity of peripheral receptor neurons in Anopheles stephensi

    OpenAIRE

    Grant, Alan; Muskavitch, Marc; O’Connell, Robert J.

    2013-01-01

    Background: Mosquitoes transmit many important diseases including malaria, dengue and yellow fever. Disease transmission from one vertebrate host to another depends on repeated blood feedings by single mosquitoes. In order for the mosquito to acquire the blood that it needs to complete oogenesis, the insect must locate a suitable host. Olfactory cues (including carbon dioxide) released by the host and detected by the mosquito are the primary signals that vector insects use for host location. ...

  5. Using a near-infrared spectrometer to estimate the age of anopheles mosquitoes exposed to pyrethroids.

    Directory of Open Access Journals (Sweden)

    Maggy T Sikulu

    Full Text Available We report on the accuracy of using near-infrared spectroscopy (NIRS to predict the age of Anopheles mosquitoes reared from wild larvae and a mixed age-wild adult population collected from pit traps after exposure to pyrethroids. The mosquitoes reared from wild larvae were estimated as <7 or ≥7 d old with an overall accuracy of 79%. The age categories of Anopheles mosquitoes that were not exposed to the insecticide papers were predicted with 78% accuracy whereas the age categories of resistant, susceptible and mosquitoes exposed to control papers were predicted with 82%, 78% and 79% accuracy, respectively. The ages of 85% of the wild-collected mixed-age Anopheles were predicted by NIRS as ≤8 d for both susceptible and resistant groups. The age structure of wild-collected mosquitoes was not significantly different for the pyrethroid-susceptible and pyrethroid-resistant mosquitoes (P = 0.210. Based on these findings, NIRS chronological age estimation technique for Anopheles mosquitoes may be independent of insecticide exposure and the environmental conditions to which the mosquitoes are exposed.

  6. Molecular identification of a myosuppressin receptor from the malaria mosquito Anopheles gambiae

    DEFF Research Database (Denmark)

    Schöller, Susanne; Belmont, Martin; Cazzamali, Giuseppe;

    2005-01-01

    The insect myosuppressins (X1DVX2HX3FLRFamide) are neuropeptides that generally block insect muscle activities. We have used the genomic sequence information from the malaria mosquito Anopheles gambiae Genome Project to clone a G protein-coupled receptor that was closely related to the two...... previously cloned and characterized myosuppressin receptors from Drosophila [Proc. Natl. Acad. Sci. USA 100 (2003) 9808]. The mosquito receptor cDNA was expressed in Chinese hamster ovary cells and was found to be activated by low concentrations of Anopheles myosuppressin (TDVDHVFLRFamide; EC50, 1.6 x 10...... identification of a mosquito neuropeptide receptor....

  7. A mosquito lipoxin/lipocalin complex mediates innate immune priming in Anopheles gambiae

    OpenAIRE

    Ramirez, Jose Luis; de Almeida Oliveira, Giselle; Calvo, Eric; Dalli, Jesmond; Colas, Romain A.; Serhan, Charles N.; Ribeiro, Jose M.; Barillas-Mury, Carolina

    2015-01-01

    Exposure of Anopheles gambiae mosquitoes to Plasmodium infection enhances the ability of their immune system to respond to subsequent infections. However, the molecular mechanism that allows the insect innate immune system to ‘remember' a previous encounter with a pathogen has not been established. Challenged mosquitoes constitutively release a soluble haemocyte differentiation factor into their haemolymph that, when transferred into Naive mosquitoes, also induces priming. Here we show that t...

  8. Larvicidal efficacy of Catharanthus roseus Linn. (Family:Apocynaceae) leaf extract and bacterial insecticideBacillus thuringiensis againstAnopheles stephensi Liston

    Institute of Scientific and Technical Information of China (English)

    Chellasamy Panneerselvam; Kadarkarai Murugan; Kalimuthu Kovendan; Palanisamy Mahesh Kumar; Sekar Ponarulselvam; Duraisamy Amerasan; Jayapal Subramaniam; Jiang-Shiou Hwang

    2013-01-01

    Objective:To explore the larvicidal activity ofCatharanthus roseus(C. roseus) leaf extract and Bacillus thuringiensis(B. thuringiensis) against the malarial vectorAnopheles stephensi(An. stephensi), when being used alone or together.Methods:The larvicidal activity was assayed at various concentrations under the laboratory and field conditions.TheLC50 andLC90 values of theC. roseus leaf extract were determined by probit analysis.Results:The plant extract showed larvicidal effects after24 h of exposure;however, the highest larval mortality was found in the petroleum ether extract ofC. roseus against the first to fourth instars larvae withLC50=3.34,4.48, 5.90 and8.17 g/L, respectively;B. thuringiensis against the first to fourth instars larvae with LC50=1.72,1.93,2.17 and2.42 g/L, respectively; and the combined treatment withLC50=2.18,2.41, 2.76 and3.22 g/L, respectively.No mortality was observed in the control.Conclusions:The petroleum ether extract ofC. roseus extract andB. thuringiensis have potential to be used as ideal eco-friendly agents for the control ofAn. stephensi in vector control programs.The combined treatment with this plant crude extract and bacterial toxin has better larvicidal efficacy against An. stephensi.

  9. Fitness consequences of larval exposure to Beauveria bassiana on adults of the malaria vector Anopheles stephensi

    NARCIS (Netherlands)

    Vogels, C.B.F.; Bukhari, T.; Koenraadt, C.J.M.

    2014-01-01

    Entomopathogenic fungi have shown to be effective in biological control of both larval and adult stages of malaria mosquitoes. However, a small fraction of mosquitoes is still able to emerge after treatment with fungus during the larval stage. It remains unclear whether fitness of these adults is af

  10. Eco-friendly drugs from the marine environment: spongeweed-synthesized silver nanoparticles are highly effective on Plasmodium falciparum and its vector Anopheles stephensi, with little non-target effects on predatory copepods.

    Science.gov (United States)

    Murugan, Kadarkarai; Panneerselvam, Chellasamy; Subramaniam, Jayapal; Madhiyazhagan, Pari; Hwang, Jiang-Shiou; Wang, Lan; Dinesh, Devakumar; Suresh, Udaiyan; Roni, Mathath; Higuchi, Akon; Nicoletti, Marcello; Benelli, Giovanni

    2016-08-01

    Mosquitoes act as vectors of devastating pathogens and parasites, representing a key threat for millions of humans and animals worldwide. The control of mosquito-borne diseases is facing a number of crucial challenges, including the emergence of artemisinin and chloroquine resistance in Plasmodium parasites, as well as the presence of mosquito vectors resistant to synthetic and microbial pesticides. Therefore, eco-friendly tools are urgently required. Here, a synergic approach relying to nanotechnologies and biological control strategies is proposed. The marine environment is an outstanding reservoir of bioactive natural products, which have many applications against pests, parasites, and pathogens. We proposed a novel method of seaweed-mediated synthesis of silver nanoparticles (AgNP) using the spongeweed Codium tomentosum, acting as a reducing and capping agent. AgNP were characterized by UV-Vis spectroscopy, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). In mosquitocidal assays, the 50 % lethal concentration (LC50) of C. tomentosum extract against Anopheles stephensi ranged from 255.1 (larva I) to 487.1 ppm (pupa). LC50 of C. tomentosum-synthesized AgNP ranged from 18.1 (larva I) to 40.7 ppm (pupa). In laboratory, the predation efficiency of Mesocyclops aspericornis copepods against A. stephensi larvae was 81, 65, 17, and 9 % (I, II, III, and IV instar, respectively). In AgNP contaminated environment, predation was not affected; 83, 66, 19, and 11 % (I, II, III, and IV). The anti-plasmodial activity of C. tomentosum extract and spongeweed-synthesized AgNP was evaluated against CQ-resistant (CQ-r) and CQ-sensitive (CQ-s) strains of Plasmodium falciparum. Fifty percent inhibitory concentration (IC50) of C. tomentosum were 51.34 μg/ml (CQ-s) and 65.17 μg/ml (CQ-r); C. tomentosum-synthesized AgNP achieved IC50 of 72.45 μg/ml (CQ-s) and 76.08

  11. Eco-friendly drugs from the marine environment: spongeweed-synthesized silver nanoparticles are highly effective on Plasmodium falciparum and its vector Anopheles stephensi, with little non-target effects on predatory copepods.

    Science.gov (United States)

    Murugan, Kadarkarai; Panneerselvam, Chellasamy; Subramaniam, Jayapal; Madhiyazhagan, Pari; Hwang, Jiang-Shiou; Wang, Lan; Dinesh, Devakumar; Suresh, Udaiyan; Roni, Mathath; Higuchi, Akon; Nicoletti, Marcello; Benelli, Giovanni

    2016-08-01

    Mosquitoes act as vectors of devastating pathogens and parasites, representing a key threat for millions of humans and animals worldwide. The control of mosquito-borne diseases is facing a number of crucial challenges, including the emergence of artemisinin and chloroquine resistance in Plasmodium parasites, as well as the presence of mosquito vectors resistant to synthetic and microbial pesticides. Therefore, eco-friendly tools are urgently required. Here, a synergic approach relying to nanotechnologies and biological control strategies is proposed. The marine environment is an outstanding reservoir of bioactive natural products, which have many applications against pests, parasites, and pathogens. We proposed a novel method of seaweed-mediated synthesis of silver nanoparticles (AgNP) using the spongeweed Codium tomentosum, acting as a reducing and capping agent. AgNP were characterized by UV-Vis spectroscopy, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). In mosquitocidal assays, the 50 % lethal concentration (LC50) of C. tomentosum extract against Anopheles stephensi ranged from 255.1 (larva I) to 487.1 ppm (pupa). LC50 of C. tomentosum-synthesized AgNP ranged from 18.1 (larva I) to 40.7 ppm (pupa). In laboratory, the predation efficiency of Mesocyclops aspericornis copepods against A. stephensi larvae was 81, 65, 17, and 9 % (I, II, III, and IV instar, respectively). In AgNP contaminated environment, predation was not affected; 83, 66, 19, and 11 % (I, II, III, and IV). The anti-plasmodial activity of C. tomentosum extract and spongeweed-synthesized AgNP was evaluated against CQ-resistant (CQ-r) and CQ-sensitive (CQ-s) strains of Plasmodium falciparum. Fifty percent inhibitory concentration (IC50) of C. tomentosum were 51.34 μg/ml (CQ-s) and 65.17 μg/ml (CQ-r); C. tomentosum-synthesized AgNP achieved IC50 of 72.45 μg/ml (CQ-s) and 76.08

  12. Antimalarial efficacy of dynamic compound of plumbagin chemical constituent from Plumbago zeylanica Linn (Plumbaginaceae) against the malarial vector Anopheles stephensi Liston (Diptera: Culicidae).

    Science.gov (United States)

    Pradeepa, Venkatraman; Sathish-Narayanan, Subbiah; Kirubakaran, Suyambulingam Arunachalam; Senthil-Nathan, Sengottayan

    2014-08-01

    In the present investigation, the effective root compound of plumbagin of Plumbago zeylanica (Plumbaginaceae) was evaluated for chemical constituent and antimalarial effect against the fourth instar larvae of Anopheles stephensi Liston (Diptera). In the chromatographic analyses of root compound with Rf value of 0.788 and NMR analyses also revealed that the effective compound contain naphthoquinone plumbagin were identified as the major chemical constituent. Larval mortality was observed after 3 h of exposure period. The plumbagin compound showed remarkable larvicidal activity against A. stephensi (LC50 32.65 and LC9072.27 ppm). Histopathological effects of compound was observed in the treated larvae. Based on the results, the plumbagin compound of P. zeylanica can be considered as a new source of natural larvicide for the control of malarial vector.

  13. Larvicidal and repellent potential of Moringa oleifera against malarial vector, Anopheles stephensi Liston (Insecta: Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    K Prabhu

    2011-04-01

    Conclusions: The present study indicates that the phytochemicals derived from M. oleifera seeds extracts are effective mosquito vector control agents and the plant extracts may be used for further integrated pest management programs.

  14. Efficacy of larvicidal and pupicidal activity of Catharanthus roseus aqueous and solvent extracts against Anopheles stephensi Liston and Culex quinquefasciatus Say (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Selladurai Subarani; Selvi Sabhanayakam; Chinnaperumal Kamaraj; Gandhi Elango; Mohamed Abdul Kadir

    2013-01-01

    Objective:To investigate the larvicidal and pupicidal activities of aqueous, ethyl acetate and methanol extracts of Catharanthus roseus (C. roseus) against malaria and filariasis vectors. Methods:The larvicidal and pupicidal activities of C. roseus leaf extracts were tested against the fourth instar larvae and pupae of Anopheles stephensi (An. stephensi) and Culex quinquefasciatus (Cx. quinquefasciatus). The mortality was observed after 24 and 48 h post the treatment. The data were subjected to probit analysis to determine the lethal concentrations (LC50 and LC90) at which 50%and 90%of the treated larvae or pupae of the tested species were killed. Results:The larval and pupal mortality were observed after 24 and 48 h of exposure of aqueous, ethyl acetate and methanol extracts of C. roseus; no mortality was observed in the control group. The LC50 values against the fourth-instar larvae of An. stephensi were 68.62 and 72.04 mg/mL for the aqueous extract, 82.47 mg/mL for the ethyl acetate extract, and 78.80 and 86.64 mg/mL for the methanol extract, while the aqueous, ethyl acetate and methanol extracts had LC50 values of 85.21, 76.84 and 94.20 mg/mL against the fourth-instar larvae of Cx. quinquefasciatus. The aqueous, ethyl acetate and methanol extracts had LC50 values of 118.08, 182.47 and 143.80 mg/mL against the pupae of An. stephensi and 146.20, 226.84 and 156.62 mg/mL against the pupae of Cx. quinquefasciatus, respectively. Conclusions: The aqueous and methanol extracts of C. roseus leaves had an excellent potential to control the malarial vector An. stephensi and filariasis vector Cx. quinquefasciatus.

  15. Bioinformatics-Based Identification of Chemosensory Proteins in African Malaria Mosquito, Anopheles gambiae

    Institute of Scientific and Technical Information of China (English)

    Zhengxi Li; Zuorui Shen; Jingjiang Zhou; Lin Field

    2003-01-01

    Chemosensory proteins (CSPs) are identifiable by four spatially conserved Cysteine residues in their primary structure or by two disulfide bridges in their tertiary structure according to the previously identified olfactory specific-D related proteins. A genomics- and bioinformatics-based approach is taken in the present study to identify the putative CSPs in the malaria-carrying mosquito, Anopheles gambiae. The results show that five out of the nine annotated candidates are the most possible Anopheles CSPs of A. gambiae. This study lays the foundation for further functional identification of Anopheles CSPs, though all of these candidates need additional experimental verification.

  16. Identification of one capa and two pyrokinin receptors from the malaria mosquito Anopheles gambiae

    DEFF Research Database (Denmark)

    Olsen, Stine S; Cazzamali, Giuseppe; Williamson, Michael;

    2007-01-01

    We cloned the cDNA of three evolutionarily related G protein-coupled receptors from the malaria mosquito Anopheles gambiae and functionally expressed them in Chinese hamster ovary cells. One receptor, Ang-Capa-R, was only activated by the two Anopheles capa neuropeptides Ang-capa-1 (GPTVGLFAFPRVa......We cloned the cDNA of three evolutionarily related G protein-coupled receptors from the malaria mosquito Anopheles gambiae and functionally expressed them in Chinese hamster ovary cells. One receptor, Ang-Capa-R, was only activated by the two Anopheles capa neuropeptides Ang-capa-1...... (GPTVGLFAFPRVamide) and Ang-capa-2 (pQGLVPFPRVamide) with EC(50) values of 8.6x10(-9)M and 3.3x10(-9)M, respectively, but not by any other known mosquito neuropeptide. The second receptor, Ang-PK-1-R, was selectively activated by the Anopheles pyrokinin-1 peptides Ang-PK-1-1 (AGGTGANSAMWFGPRLamide) and Ang-PK-1......-2 (AAAMWFGPRLamide) with EC(50) values of 3.3x10(-8)M and 2.5x10(-8)M, respectively, but not by mosquito capa or pyrokinin-2 peptides. For the third receptor, Ang-PK-2-R, the most potent ligands were the pyrokinin-2 peptides Ang-PK-2-1 (DSVGENHQRPPFAPRLamide) and Ang-PK-2-2 (NLPFSPRLamide) with EC(50) values of 5.2x...

  17. Larvicidal efficacy of Cleistanthus collinus (Roxb.) (Euphorbiaceae) leaf extracts against vector mosquitoes (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Arivoli S; Samuel T

    2011-01-01

    Objective:To determine the larvicidal activity of Cleistanthus collinus (C. collinus) leaf extracts against Aedes aegypti, Anopheles stephensi (An. stephensi) and Culex quinquefasciatus. Methods:The larvicidal activity was determined against three vector mosquito species at concentrations of 250, 500, 750 and 1000 ppm. Larval mortality was assessed after 24 hours. Results:The leaf extracts of C. collinus was found to exhibit a larvicidal activity against the larvae of An. stephensi with a LC50 value of 399.72 ppm. Conclusions:The results indicate moderate level of larvicidal activity against vector mosquitoes.

  18. Rhodopsin coexpression in UV photoreceptors of Aedes aegypti and Anopheles gambiae mosquitoes

    OpenAIRE

    Hu, Xiaobang; Leming, Matthew T; Whaley, Michelle A.; O'Tousa, Joseph E.

    2014-01-01

    Differential rhodopsin gene expression within specialized R7 photoreceptor cells divides the retinas of Aedes aegypti and Anopheles gambiae mosquitoes into distinct domains. The two species express the rhodopsin orthologs Aaop8 and Agop8, respectively, in a large subset of these R7 photoreceptors that function as ultraviolet receptors. We show here that a divergent subfamily of mosquito rhodopsins, Aaop10 and Agop10, is coexpressed in these R7 photoreceptors. The properties of the A. aegypti ...

  19. Extensive circadian and light regulation of the transcriptome in the malaria mosquito Anopheles gambiae

    OpenAIRE

    Rund, Samuel SC; James E. Gentile; Duffield, Giles E.

    2013-01-01

    Background Mosquitoes exhibit 24 hr rhythms in flight activity, feeding, reproduction and development. To better understand the molecular basis for these rhythms in the nocturnal malaria vector Anopheles gambiae, we have utilized microarray analysis on time-of-day specific collections of mosquitoes over 48 hr to explore the coregulation of gene expression rhythms by the circadian clock and light, and compare these with the 24 hr rhythmic gene expression in the diurnal Aedes aegypti dengue vec...

  20. Development of sporogonic cycle of Plasmodium vivax in experimentally infected Anopheles albimanus mosquitoes

    OpenAIRE

    Martha L. Salas; Romero, Jackeline F.; Yesid Solarte; Victor Olano; Myriam A. Herrera; Sócrates Herrera

    1994-01-01

    The sporogonic cycle of Plasmodium vivax was established and maintained under laboratory conditions in two different strains of Anopheles albimanus mosquitoes using as a parasite source blood from human patients or from Aotus monkeys infected with the VCC-2 P.vivax colombian isolate. Both the Tecojate strain isolate from Guatemala and the Cartagena strain from the colombian Pacific coast were susceptible to infections with P.vivax. A higher percentage of Cartagena mosquitoes was infected per ...

  1. The role of cow urine in the oviposition site preference of culicine and Anopheles mosquitoes

    OpenAIRE

    Kweka Eliningaya J; Owino Eunice A; Mwang'onde Beda J; Mahande Aneth M; Nyindo Mramba; Mosha Franklin

    2011-01-01

    Abstract Background Chemical and behavioural ecology of mosquitoes plays an important role in the development of chemical cue based vector control. To date, studies available have focused on evaluating mosquito attractants and repellents of synthetic and human origins. This study, however, was aimed at seasonal evaluation of the efficiency of cow urine in producing oviposition cues to Anopheles gambiae s.l. and Culex quinquefasciatus in both laboratory and field conditions. Methods Ovipositio...

  2. The nicotinic acetylcholine receptor gene family of the malaria mosquito, Anopheles gambiae.

    Science.gov (United States)

    Jones, Andrew K; Grauso, Marta; Sattelle, David B

    2005-02-01

    Nicotinic acetylcholine receptors (nAChRs) mediate fast cholinergic synaptic transmission in the insect nervous system and are targets of widely selling insecticides. We have identified the nAChR gene family from the genome of the malaria mosquito vector, Anopheles gambiae, to be the second complete insect nAChR gene family described following that of Drosophila melanogaster. Like Drosophila, Anopheles possesses 10 nAChR subunits with orthologous relationships evident between the two insects. Interestingly, the Anopheles orthologues of Dbeta2 and Dbeta3 possess the vicinal cysteines that define alpha subunits. As with Dalpha4 and Dalpha6, the Anopheles orthologues are alternatively spliced at equivalent exons. Reverse transcription-polymerase chain reaction analysis shows that RNA A-to-I editing sites conserved between Dalpha6 of Drosophila and alpha7-2 of the tobacco budworm, Heliothis virescens, are not shared with the equivalent nAChR subunit of Anopheles. Indeed, RNA-editing sites identified in functionally significant regions of Dbeta1, Dalpha5, and Dalpha6 are not conserved in the mosquito orthologues, indicating considerable divergence of RNA molecules targeted for editing within the insect order Diptera. These findings shed further light on the diversity of nAChR subunits and may present a useful basis for the development of improved malaria control agents by enhancing our understanding of a validated mosquito insecticide target.

  3. The effect of temperature on Anopheles mosquito population dynamics and the potential for malaria transmission.

    Directory of Open Access Journals (Sweden)

    Lindsay M Beck-Johnson

    Full Text Available The parasites that cause malaria depend on Anopheles mosquitoes for transmission; because of this, mosquito population dynamics are a key determinant of malaria risk. Development and survival rates of both the Anopheles mosquitoes and the Plasmodium parasites that cause malaria depend on temperature, making this a potential driver of mosquito population dynamics and malaria transmission. We developed a temperature-dependent, stage-structured delayed differential equation model to better understand how climate determines risk. Including the full mosquito life cycle in the model reveals that the mosquito population abundance is more sensitive to temperature than previously thought because it is strongly influenced by the dynamics of the juvenile mosquito stages whose vital rates are also temperature-dependent. Additionally, the model predicts a peak in abundance of mosquitoes old enough to vector malaria at more accurate temperatures than previous models. Our results point to the importance of incorporating detailed vector biology into models for predicting the risk for vector borne diseases.

  4. A natural Anopheles-associated Penicillium chrysogenum enhances mosquito susceptibility to Plasmodium infection

    Science.gov (United States)

    Angleró-Rodríguez, Yesseinia I.; Blumberg, Benjamin J.; Dong, Yuemei; Sandiford, Simone L.; Pike, Andrew; Clayton, April M.; Dimopoulos, George

    2016-01-01

    Whereas studies have extensively examined the ability of bacteria to influence Plasmodium infection in the mosquito, the tripartite interactions between non-entomopathogenic fungi, mosquitoes, and Plasmodium parasites remain largely uncharacterized. Here we report the isolation of a common mosquito-associated ascomycete fungus, Penicillium chrysogenum, from the midgut of field-caught Anopheles mosquitoes. Although the presence of Pe. chrysogenum in the Anopheles gambiae midgut does not affect mosquito survival, it renders the mosquito significantly more susceptible to Plasmodium infection through a secreted heat-stable factor. We further provide evidence that the mechanism of the fungus-mediated modulation of mosquito susceptibility to Plasmodium involves an upregulation of the insect’s ornithine decarboxylase gene, which sequesters arginine for polyamine biosynthesis. Arginine plays an important role in the mosquito’s anti-Plasmodium defense as a substrate of nitric oxide production, and its availability therefore has a direct impact on the mosquito’s susceptibility to the parasite. While this type of immunomodulatory mechanism has already been demonstrated in other host-pathogen interaction systems, this is the first report of a mosquito-associated fungus that can suppress the mosquito’s innate immune system in a way that would favor Plasmodium infection and possibly malaria transmission. PMID:27678168

  5. Control of pyrethroid-resistant Anopheles gambiae and Culex quinquefasciatus mosquitoes with chlorfenapyr in Benin

    NARCIS (Netherlands)

    N'Guessan, R.; Boko, P.; Odjo, A.; Knols, B.G.J.; Akogbeto, M.; Rowland, M.

    2009-01-01

    Objective To compare the efficacy of chlorfenapyr applied on mosquito nets and as an indoor residual spray against populations of Anopheles gambiae and Culex quinquefasciatus in an area of Benin that shows problematic levels of pyrethroid resistance. Method Eight-week trial conducted in experimental

  6. Olfaction in the malaria mosquito Anopheles gambiae : Electrophysiology and identification of kairomones

    NARCIS (Netherlands)

    Meijerink, J.

    1999-01-01

    Female mosquitoes of the species Anopheles gambiae Giles sensu stricto are important vectors of human malaria in Africa. It is generally assumed that they locate their human host by odours. These odours are detected by olfactory receptor neurons situated within cuticular extensions on the antenna. T

  7. Effect of larval crowding on mating competitiveness of Anopheles gambiae mosquitoes

    NARCIS (Netherlands)

    Ng'habi, K.R.; John, B.; Nkwengulila, G.; Knols, B.G.J.; Killeen, G.F.; Ferguson, H.M.

    2005-01-01

    Background: The success of sterile or transgenic Anopheles for malaria control depends on their mating competitiveness within wild populations. Current evidence suggests that transgenic mosquitoes have reduced fitness. One means of compensating for this fitness deficit would be to identify environme

  8. The effect of sublethal exposure to temephos and propoxur on reproductive fitness and its influence on circadian rhythms of pupation and adult emergence in Anopheles stephensi Liston-a malaria vector.

    Science.gov (United States)

    Sanil, Deepak; Shetty, Nadikere Jaya

    2012-07-01

    The present study was undertaken to investigate the effects of organophosphate and carbamate insecticides namely, temephos and propoxur respectively, on the life history of Anopheles stephensi Liston (Culicidae) under laboratory conditions. The late third instar larvae of the mosquito were exposed to sublethal concentrations of temephos and propoxur at LC(10), LC(30) and LC(50), respectively, and adult survivors were evaluated for fitness parameters. Sublethal effects were also evaluated in subsequent generations. Fecundity, egg hatchability, sex ratio, adult longevity and morphology of gonads were the end points studied and compared to the untreated control. Adverse changes in developmental traits were mainly observed in fecundity, egg hatchability and sex ratio. However, significant differences in adult longevity were observed in the insecticide-exposed population. Pleiotropic effects through prolonged larval duration and enhanced longevity of adults were observed. Morphology of gonads in the insecticide-exposed population was severely affected and is represented by rudimentary and atrophied testes, and the size of the vas deferens was very much reduced when compared to that of the control. In another set of experiments, circadian rhythm (for pupation and adult emergence) of LC(10), LC(30) and LC(50) values to abovementioned insecticides exposed to late third instar larvae was studied. Pupation and adult emergence rhythms were found to be disturbed with an increase in concentrations of insecticides when compared to that of untreated control.

  9. Hemolytic C-Type Lectin CEL-III from Sea Cucumber Expressed in Transgenic Mosquitoes Impairs Malaria Parasite Development

    OpenAIRE

    Shigeto Yoshida; Yohei Shimada; Daisuke Kondoh; Yoshiaki Kouzuma; Ghosh, Anil K.; Marcelo Jacobs-Lorena; Sinden, Robert E.

    2007-01-01

    The midgut environment of anopheline mosquitoes plays an important role in the development of the malaria parasite. Using genetic manipulation of anopheline mosquitoes to change the environment in the mosquito midgut may inhibit development of the malaria parasite, thus blocking malaria transmission. Here we generate transgenic Anopheles stephensi mosquitoes that express the C-type lectin CEL-III from the sea cucumber, Cucumaria echinata, in a midgut-specific manner. CEL-III has strong and ra...

  10. A mosquito lipoxin/lipocalin complex mediates innate immune priming in Anopheles gambiae.

    Science.gov (United States)

    Ramirez, Jose Luis; de Almeida Oliveira, Giselle; Calvo, Eric; Dalli, Jesmond; Colas, Romain A; Serhan, Charles N; Ribeiro, Jose M; Barillas-Mury, Carolina

    2015-01-01

    Exposure of Anopheles gambiae mosquitoes to Plasmodium infection enhances the ability of their immune system to respond to subsequent infections. However, the molecular mechanism that allows the insect innate immune system to 'remember' a previous encounter with a pathogen has not been established. Challenged mosquitoes constitutively release a soluble haemocyte differentiation factor into their haemolymph that, when transferred into Naive mosquitoes, also induces priming. Here we show that this factor consists of a Lipoxin/Lipocalin complex. We demonstrate that innate immune priming in mosquitoes involves a persistent increase in expression of Evokin (a lipid carrier of the lipocalin family), and in their ability to convert arachidonic acid to lipoxins, predominantly Lipoxin A4. Plasmodium ookinete midgut invasion triggers immune priming by inducing the release of a mosquito lipoxin/lipocalin complex. PMID:26100162

  11. A mosquito lipoxin/lipocalin complex mediates innate immune priming in Anopheles gambiae

    Science.gov (United States)

    Ramirez, Jose Luis; de Almeida Oliveira, Giselle; Calvo, Eric; Dalli, Jesmond; Colas, Romain A.; Serhan, Charles N.; Ribeiro, Jose M.; Barillas-Mury, Carolina

    2015-01-01

    Exposure of Anopheles gambiae mosquitoes to Plasmodium infection enhances the ability of their immune system to respond to subsequent infections. However, the molecular mechanism that allows the insect innate immune system to ‘remember' a previous encounter with a pathogen has not been established. Challenged mosquitoes constitutively release a soluble haemocyte differentiation factor into their haemolymph that, when transferred into Naive mosquitoes, also induces priming. Here we show that this factor consists of a Lipoxin/Lipocalin complex. We demonstrate that innate immune priming in mosquitoes involves a persistent increase in expression of Evokin (a lipid carrier of the lipocalin family), and in their ability to convert arachidonic acid to lipoxins, predominantly Lipoxin A4. Plasmodium ookinete midgut invasion triggers immune priming by inducing the release of a mosquito lipoxin/lipocalin complex. PMID:26100162

  12. Chemical composition and larvicidal activity of essential oil of Cupressus arizonica E.L. Greene against malaria vector Anopheles stephensi Liston (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Mohammad Mehdi Sedaghat

    2011-01-01

    Full Text Available Background: Using botanical insecticides as an alternative biocontrol technique for vector control is considered by some scientists. Materials and Methods: Chemical composition of the essential oil was analyzed using gas chromatography-mass spectrometry (GC-MS. In addition, the mosquito larvicidal activity of leaf essential oil of Cupressus arizonica was investigated against fourth instar larvae of laboratory-reared An. stephensi according to the method of the World Health Organization. Results: Of 46 constituents in the oil, limonene (14.44%, umbellulone (13.25% and α-pinene (11% were determined as the main constituents. Cupressus arizonica volatile oil showed significant larvicidal activity against An. stephensi with LC 50 and LC 90 values 79.30 ppm and 238.89 ppm respectively. Clear dose-response relationships were established with the highest dose of 160 ppm essential oil with almost 100% mortality. Discussion: The results from this study revealed that C. arizonica essential oil could be considered as a natural larvicide against An. stephensi. However, the field evaluation of the formulation is necessary.

  13. West African Anopheles gambiae mosquitoes harbor a taxonomically diverse virome including new insect-specific flaviviruses, mononegaviruses, and totiviruses.

    Science.gov (United States)

    Fauver, Joseph R; Grubaugh, Nathan D; Krajacich, Benjamin J; Weger-Lucarelli, James; Lakin, Steven M; Fakoli, Lawrence S; Bolay, Fatorma K; Diclaro, Joseph W; Dabiré, Kounbobr Roch; Foy, Brian D; Brackney, Doug E; Ebel, Gregory D; Stenglein, Mark D

    2016-11-01

    Anopheles gambiae are a major vector of malaria in sub-Saharan Africa. Viruses that naturally infect these mosquitoes may impact their physiology and ability to transmit pathogens. We therefore used metagenomics sequencing to search for viruses in adult Anopheles mosquitoes collected from Liberia, Senegal, and Burkina Faso. We identified a number of virus and virus-like sequences from mosquito midgut contents, including 14 coding-complete genome segments and 26 partial sequences. The coding-complete sequences define new viruses in the order Mononegavirales, and the families Flaviviridae, and Totiviridae. The identification of a flavivirus infecting Anopheles mosquitoes broadens our understanding of the evolution and host range of this virus family. This study increases our understanding of virus diversity in general, begins to define the virome of a medically important vector in its natural setting, and lays groundwork for future studies examining the potential impact of these viruses on anopheles biology and disease transmission. PMID:27639161

  14. A Possible Mechanism for the Suppression of Plasmodium berghei Development in the Mosquito Anopheles gambiae by the Microsporidian Vavraia culicis

    OpenAIRE

    Bargielowski, Irka; Koella, Jacob C

    2009-01-01

    Background Microsporidian parasites of mosquitoes offer a possible way of controlling malaria, as they impede the development of Plasmodium parasites within the mosquito. The mechanism involved in this interference process is unknown. Methodology We evaluated the possibility that larval infection by a microsporidian primes the immune system of adult mosquitoes in a way that enables a more effective anti-Plasmodium response. To do so, we infected 2-day old larvae of the mosquito Anopheles gamb...

  15. Evaluation of selected South African ethnomedicinal plants as mosquito repellents against the Anopheles arabiensis mosquito in a rodent model

    Directory of Open Access Journals (Sweden)

    Folb Peter I

    2010-10-01

    Full Text Available Abstract Background This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic, that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito repellent properties. Methods Extracts of a selection of South African taxa were tested for repellency properties in an applicable mosquito feeding-probing assay using unfed female Anopheles arabiensis. Results Although a water extract of the roots of Chenopodium opulifolium was found to be 97% as effective as DEET after 2 mins, time lag studies revealed a substantial reduction in efficacy (to 30% within two hours. Conclusions None of the plant extracts investigated exhibited residual repellencies >60% after three hours.

  16. Potential Test of Papaya Leaf and Seed Extract (Carica Papaya) as Larvicides against Anopheles Mosquito Larvae Mortality. SP IN Jayapura, Papua Indonesia

    OpenAIRE

    Arsunan

    2015-01-01

    Anopheles mosquitoes, sp is the main vector of malaria disease that is widespread in many parts of the world including in Papua Province. There are four speciesof Anopheles mosquitoes, sp, in Papua namely: An.farauti, An.koliensis, An. subpictus, and An.punctulatus. Larviciding synthetic cause resistance. This study aims to analyze the potential of papaya leaf and seeds extracts (Carica papaya) as larvicides against the mosquitoes Anopheles sp. The experiment was conducted at the Laboratory o...

  17. Repellency Effects of Essential Oils of Myrtle (Myrtus communis, Marigold (Calendula officinalis Compared with DEET against Anopheles stephensi on Human Volunteers

    Directory of Open Access Journals (Sweden)

    M Tavassoli

    2011-12-01

    Full Text Available Background: Malaria and leishmaniasis are two most significant parasitic diseases which are endemic in Iran. Over the past decades, interest in botanical repellents has increased as a result of safety to human. The comparative effi­cacy of essential oils of two native plants, myrtle (Myrtus communis and marigold (Calendula officinalis collected from natural habitats at southern Iran was compared with DEET as synthetic repellent against Anopheles stephensi on human subjects under laboratory condition. Methods:  Essential oils from two species of native plants were obtained by Clevenger-type water distillation. The protec­tion time of DEET, marigold and myrtle was assessed on human subject using screened cage method against An. stephensi. The effective dose of 50% essential oils of two latter species and DEET were determined by modified ASTM method. ED50 and ED90 values and related statistical parameters were calculated by probit analysis.   Results: The protection time of 50% essential oils of marigold and myrtle were respectively 2.15 and 4.36 hours com­pared to 6.23 hours for DEET 25%. The median effective dose (ED50 of 50% essential oils was 0.1105 and 0.6034 mg/cm2 respectively in myrtle and marigold. The figure for DEET was 0.0023 mg/cm2. Conclusion: This study exhibited that the repellency of both botanical repellents was generally lower than DEET as a synthetic repellent. However the 50% essential oil of myrtle showed a moderate repellency effects compared to mari­gold against An. stephensi.

  18. Repellency Effects of Essential Oils of Myrtle (Myrtus Communis, Marigold (Calendula Officinalis Compared with DEET Against Anopheles Stephensi on Human Volunteers

    Directory of Open Access Journals (Sweden)

    M Khoobdel

    2011-12-01

    Full Text Available Background: Malaria and leishmaniasis are two most significant parasitic diseases which are endemic in Iran. Over the past decades, interest in botanical repellents has increased as a result of safety to human. The comparative effi­cacy of essential oils of two native plants, myrtle (Myrtus communis and marigold (Calendula officinalis collected from natural habitats at southern Iran was compared with DEET as synthetic repellent against Anopheles stephensi on human subjects under laboratory condition. Methods: Essential oils from two species of native plants were obtained by Clevenger-type water distillation. The protec­tion time of DEET, marigold and myrtle was assessed on human subject using screened cage method against An. stephensi. The effective dose of 50% essential oils of two latter species and DEET were determined by modified ASTM method. ED50 and ED90 values and related statistical parameters were calculated by probit analysis. Results: The protection time of 50% essential oils of marigold and myrtle were respectively 2.15 and 4.36 hours com­pared to 6.23 hours for DEET 25%. The median effective dose (ED50 of 50% essential oils was 0.1105 and 0.6034 mg/cm2 respectively in myrtle and marigold. The figure for DEET was 0.0023 mg/cm2.Conclusion: This study exhibited that the repellency of both botanical repellents was generally lower than DEET as a synthetic repellent. However the 50% essential oil of myrtle showed a moderate repellency effects compared to mari­gold against An. stephensi.

  19. Fauna and some biological characteristics of Anopheles mosquitoes (Diptera:Culicidae) in Kalaleh County, Golestan Province, northeast of lran

    Institute of Scientific and Technical Information of China (English)

    Aioub Sofizadeh; Hamideh Edalat; Mohammad Reza Abai; Ahmad Ali Hanafi-Bojd

    2016-01-01

    Objective: To determine fauna and some ecological aspects of Anopheles mosquitoes in northeast of Iran. Methods: In this descriptive study, 3 villages in Kalaleh County were selected in different geographical zones. Anopheles mosquitoes were collected biweekly from May to October using standard dipping method for larvae, and hand catch, total catch, artificial pit shelter as well as night-biting collections on human and animal baits for adults. Results: Totally 399 larvae and 2 602 adults of Anopheles mosquitoes were collected and identified as 2 species: Anopheles superpictus s.l. (An. superpictus s.l.) and Anopheles maculipennis s.l. The dominant species was An. superpictus s.l. (92.1%). Activity of these mosquitoes found to be started from middle of May and extended till September with two peaks of activity in July and August. Conclusions: An. superpictus s.l. as one of the main malaria vectors in Iran as well as some other parts of the world is the dominant species in the study area. This species has high potential for transmission and possibility of establishing a transmission cycle with low abundance. Other species, Anopheles maculipennis s.l. also has introduced as a malaria vector in northern parts of Iran. As this Anopheles is a complex species, genetic studies are recommended to determine the members of this complex in the study area.

  20. Olfaction in the malaria mosquito Anopheles gambiae : Electrophysiology and identification of kairomones

    OpenAIRE

    Meijerink, J

    1999-01-01

    Female mosquitoes of the species Anopheles gambiae Giles sensu stricto are important vectors of human malaria in Africa. It is generally assumed that they locate their human host by odours. These odours are detected by olfactory receptor neurons situated within cuticular extensions on the antenna. These cuticular extensions, called sensilla, contain numerous pores through which the odours can enter the sensillum and reach the olfactory receptor neuron membrane. Despite the fact that these mos...

  1. Anopheles gambiae mosquito isolated neurons : a new biological model for optimizing insecticide/repellent efficacy

    OpenAIRE

    Lavialle-Defaix, C.; Apaire-Marchais, V; Legros, C.; Pennetier, Cédric; Mohamed, A; P. Licznar; Corbel, Vincent; Lapied, B

    2011-01-01

    To understand better the mode of action of insecticides and repellents used in vector-borne diseases control, we developed a new biological model based on mosquito neurons isolated from adults Anopheles gambiae heads. This cellular model is well adapted to multidisciplinary approaches: electrophysiology, pharmacology, molecular biology and biochemical assays. Using RT-PCR, we demonstrated that isolated neurons express the nicotinic acetylcholine receptor subunit alpha 1 (Ag alpha 1 nAchR), tw...

  2. Biochemical Characterization of Anopheles gambiae SRPN6, a Malaria Parasite Invasion Marker in Mosquitoes

    OpenAIRE

    Chunju An; Yasuaki Hiromasa; Xin Zhang; Scott Lovell; Michal Zolkiewski; John M Tomich; Kristin Michel

    2012-01-01

    Serine proteinase inhibitors of the serpin family are well known as negative regulators of hemostasis, thrombolysis and innate immune responses. Additionally, non-inhibitory serpins serve functions as chaperones, hormone transporters, or anti-angiogenic factors. In the African malaria mosquito, Anopheles gambiae s.s., at least three serpins (SRPNs) are implicated in the innate immune response against malaria parasites. Based on reverse genetic and cell biological analyses, AgSRPN6 limits para...

  3. The STAT pathway mediates late phase immunity against Plasmodium in the mosquito Anopheles gambiae

    OpenAIRE

    Gupta, Lalita; Molina-Cruz, Alvaro; Kumar, Sanjeev; Rodrigues, Janneth; Dixit, Rajnikant; Zamora, Rodolfo E.; Barillas-Mury, Carolina

    2009-01-01

    The STAT family of transcription factors activate expression of immune system genes in vertebrates. The ancestral STAT gene (AgSTAT-A) appears to have duplicated in the mosquito Anopheles gambiae, giving rise to a second intronless STAT gene (AgSTAT-B), which we show regulates AgSTAT-A expression in adult females. AgSTAT-A participates in the transcriptional activation of nitric oxide synthase (NOS) in response to bacterial and plasmodial infection. Activation of this pathway, however, is not...

  4. Hemocyte differentiation mediates innate immune memory in Anopheles gambiae mosquitoes.

    Science.gov (United States)

    Rodrigues, Janneth; Brayner, Fábio André; Alves, Luiz Carlos; Dixit, Rajnikant; Barillas-Mury, Carolina

    2010-09-10

    Mosquito midgut invasion by ookinetes of the malaria parasite Plasmodium disrupts the barriers that normally prevent the gut microbiota from coming in direct contact with epithelial cells. This triggers a long-lived response characterized by increased abundance of granulocytes, a subpopulation of hemocytes that circulates in the insect's hemocoel, and enhanced immunity to bacteria that indirectly reduces survival of Plasmodium parasites upon reinfection. In mosquitoes, differentiation of hemocytes was necessary and sufficient to confer innate immune memory. PMID:20829487

  5. Hemocyte Differentiation Mediates Innate Immune Memory in Anopheles gambiae Mosquitoes

    OpenAIRE

    Rodrigues, Janneth; Brayner, Fábio André; Alves, Luiz Carlos; Dixit, Rajnikant; Barillas-Mury, Carolina

    2010-01-01

    Mosquito midgut invasion by ookinetes of the malaria parasite Plasmodium disrupts the barriers that normally prevent the gut microbiota from coming in direct contact with epithelial cells. This triggers a long-lived response characterized by increased abundance of granulocytes, a subpopulation of hemocytes, circulating in the insect’s hemocoel, and enhanced immunity to bacteria that indirectly reduces survival of Plasmodium parasites upon reinfection. In mosquitoes, differentiation of hemocyt...

  6. Hemocyte Differentiation Mediates Innate Immune Memory in Anopheles gambiae Mosquitoes

    Science.gov (United States)

    Rodrigues, Janneth; Brayner, Fábio André; Alves, Luiz Carlos; Dixit, Rajnikant; Barillas-Mury, Carolina

    2012-01-01

    Mosquito midgut invasion by ookinetes of the malaria parasite Plasmodium disrupts the barriers that normally prevent the gut microbiota from coming in direct contact with epithelial cells. This triggers a long-lived response characterized by increased abundance of granulocytes, a subpopulation of hemocytes, circulating in the insect’s hemocoel, and enhanced immunity to bacteria that indirectly reduces survival of Plasmodium parasites upon reinfection. In mosquitoes, differentiation of hemocytes was necessary and sufficient to confer innate immune memory. PMID:20829487

  7. Evaluation of selected South African ethnomedicinal plants as mosquito repellents against the Anopheles arabiensis mosquito in a rodent model

    OpenAIRE

    Folb Peter I; Bhagwandin Niresh; Newmarch Marion; Crouch Neil R; Maharaj Vinesh; Maharaj Rajendra; Pillay Pamisha; Gayaram Reshma

    2010-01-01

    Abstract Background This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic), that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito repellent properties. Methods Extracts of a selection of South African taxa were tested for repellency properties in an applicable mosquito feeding-probing assay using unfed female Anopheles arabiensis. Results Although a water extract of the roots of Chenopodiu...

  8. Bacterial diversity associated with wild caught Anopheles mosquitoes from Dak Nong Province, Vietnam using culture and DNA fingerprint.

    Directory of Open Access Journals (Sweden)

    Chung Thuy Ngo

    Full Text Available Microbiota of Anopheles midgut can modulate vector immunity and block Plasmodium development. Investigation on the bacterial biodiversity in Anopheles, and specifically on the identification of bacteria that might be used in malaria transmission blocking approaches, has been mainly conducted on malaria vectors of Africa. Vietnam is an endemic country for both malaria and Bancroftian filariasis whose parasitic agents can be transmitted by the same Anopheles species. No information on the microbiota of Anopheles mosquitoes in Vietnam was available previous to this study.The culture dependent approach, using different mediums, and culture independent (16S rRNA PCR - TTGE method were used to investigate the bacterial biodiversity in the abdomen of 5 Anopheles species collected from Dak Nong Province, central-south Vietnam. Molecular methods, sequencing and phylogenetic analysis were used to characterize the microbiota.The microbiota in wild-caught Anopheles was diverse with the presence of 47 bacterial OTUs belonging to 30 genera, including bacterial genera impacting Plasmodium development. The bacteria were affiliated with 4 phyla, Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria, the latter being the dominant phylum. Four bacterial genera are newly described in Anopheles mosquitoes including Coxiella, Yersinia, Xanthomonas, and Knoellia. The bacterial diversity per specimen was low ranging from 1 to 4. The results show the importance of pairing culture and fingerprint methods to better screen the bacterial community in Anopheles mosquitoes.Sampled Anopheles species from central-south Vietnam contained a diverse bacterial microbiota that needs to be investigated further in order to develop new malaria control approaches. The combination of both culture and DNA fingerprint methods allowed a thorough and complementary screening of the bacterial community in Anopheles mosquitoes.

  9. Bacterial Diversity Associated with Wild Caught Anopheles Mosquitoes from Dak Nong Province, Vietnam Using Culture and DNA Fingerprint

    Science.gov (United States)

    Ngo, Chung Thuy; Aujoulat, Fabien; Veas, Francisco; Jumas-Bilak, Estelle; Manguin, Sylvie

    2015-01-01

    Background Microbiota of Anopheles midgut can modulate vector immunity and block Plasmodium development. Investigation on the bacterial biodiversity in Anopheles, and specifically on the identification of bacteria that might be used in malaria transmission blocking approaches, has been mainly conducted on malaria vectors of Africa. Vietnam is an endemic country for both malaria and Bancroftian filariasis whose parasitic agents can be transmitted by the same Anopheles species. No information on the microbiota of Anopheles mosquitoes in Vietnam was available previous to this study. Method The culture dependent approach, using different mediums, and culture independent (16S rRNA PCR – TTGE) method were used to investigate the bacterial biodiversity in the abdomen of 5 Anopheles species collected from Dak Nong Province, central-south Vietnam. Molecular methods, sequencing and phylogenetic analysis were used to characterize the microbiota. Results and Discussion The microbiota in wild-caught Anopheles was diverse with the presence of 47 bacterial OTUs belonging to 30 genera, including bacterial genera impacting Plasmodium development. The bacteria were affiliated with 4 phyla, Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria, the latter being the dominant phylum. Four bacterial genera are newly described in Anopheles mosquitoes including Coxiella, Yersinia, Xanthomonas, and Knoellia. The bacterial diversity per specimen was low ranging from 1 to 4. The results show the importance of pairing culture and fingerprint methods to better screen the bacterial community in Anopheles mosquitoes. Conclusion Sampled Anopheles species from central-south Vietnam contained a diverse bacterial microbiota that needs to be investigated further in order to develop new malaria control approaches. The combination of both culture and DNA fingerprint methods allowed a thorough and complementary screening of the bacterial community in Anopheles mosquitoes. PMID:25747513

  10. Studies on the impact of biosynthesized silver nanoparticles (AgNPs) in relation to malaria and filariasis vector control against Anopheles stephensi Liston and Culex quinquefasciatus Say (Diptera: Culicidae).

    Science.gov (United States)

    Subarani, Selladurai; Sabhanayakam, Selvi; Kamaraj, Chinnaperumal

    2013-02-01

    Biosynthesized nanoparticles have been achieved using environmentally acceptable plant extract and eco-friendly reducing and capping agents. The present study was based on assessments of the larvicidal activities to determine the efficacies of synthesized silver nanoparticles (AgNPs) using aqueous leaf extract of Vinca rosea (L.) (Apocynaceae) against the larvae of malaria vector Anopheles stephensi Liston and filariasis vector Culex quinquefasciatus Say (Diptera: Culicidae). Larvae were exposed to varying concentrations of aqueous extract of V. rosea and synthesized AgNPs for 24, 48, and 72 h. AgNPs were rapidly synthesized using the leaf extract of V. rosea, and the formation of nanoparticles was observed within 15 min. The results recorded from UV-Vis spectrum, Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) support the biosynthesis and characterization of AgNPs. The formation of the AgNPs synthesized from the XRD spectrum compared with the Bragg reflections at 2θ = 29.36, 38.26, 44.51, 63.54, and 77.13° which can be indexed to the (121), (111), (200), (220), and (311) orientations, respectively, confirmed the presence of AgNPs. The FTIR spectra of AgNPs exhibited prominent peaks at the spectra showed sharp and strong absorption band at 3,406.71 to 3,431.90 cm(-1) double in case of NH(2) group of a primary amine (N-H stretch). The presence of the sharp peak at 2,926.54 to 2,925.80 cm(-1) very broad often looks like distorted baseline (O-H carboxylic acids). The band 1,633.26 to 1,625.81 cm(-1) was assigned to C = C alkenes, aromatic ring stretching vibration, respectively. SEM analysis of the synthesized AgNPs clearly showed the clustered and irregular shapes, mostly aggregated and having the size of 120 nm. TEM reveals spherical shape of synthesized AgNPs. Particle size analysis revealed that the size of particles ranges from 25 to 47 nm with average size of 34.61 nm

  11. Sampling of adult mosquito vectors with Mosquito Magnet Pro in Panaji, Goa, India.

    Science.gov (United States)

    Korgaonkar, Nandini S; Kumar, Ashwani; Yadav, Rajpal S; Kabadi, Dipak; Dash, Aditya P

    2008-12-01

    For mosquito vector population monitoring, a new commercial trap, Mosquito Magnet Pro (MM-PRO), was tested for its usefulness in Goa, India. Anopheles stephensi was tested for the presence of Plasmodium sporozoite infection in the salivary glands. Using the MM-PRO 24 h a day for 34 days, 2,329 mosquitoes belonging to 16 species were collected. These included 6 species each of the genera Anopheles and Culex, 2 species of Aedes, and 1 each of Mansonia and Armigeres. Most (91%) of the mosquitoes caught were females. Among these the number and percentage of each species were Anopheles stephensi 59 (2.78%), Culex quinquefasciatus 1013 (47.78%), Culex vishnui 551 (26.0%), Mansonia uniformis 216 (10.19%), and Aedes albopictus 1 (0.04%). Of the 54 An. stephensi females tested for the presence of circumsporozoite protein (CSP) by an ELISA technique, 1 was found to be Plasmodium falciparum CSP positive. The MM-PRO device was found useful for mosquito population sampling in the urban setting of Goa. PMID:19181075

  12. Diversity and distribution of tree hole mosquitoes in Puducherry Union Territory, India

    Institute of Scientific and Technical Information of China (English)

    Periyasamy Senthamarai Selvan; Arulsamy Jebanesan; Chinnusamy Makesh Kumar

    2015-01-01

    Objective:To study diversity and distribution of tree hole mosquitoes at Puducherry Union Territory. Methods:Random collections were carried out in tree holes at collection sites by using suction tube. Mosquitoes are identified by standard entomological procedures. Results: A total of 235 mosquitoes were collected from tree holes, comprising 3 genera and 12 species. They are,Aedes aegypti, Aedes albopictus, Aedes stokesi, Aedes simpsoni, Anopheles subpictus, Anopheles stephensi, Anopheles culiciformis, Anopheles maculatus, Culex quinquefasciatus, Culex pseudovishnui, Culex tritaeniorhynchus, and Culex decens. The results reveal thatAedes species is the dominant species in tree holes. Simpson’s dominance index and Shanon-Wiener diversity index of 0.182 7 and 0.833 6 were respectively recorded for all tree hole mosquitoes. Conclusions:The diversity studies of tree hole mosquitoes in the study area are necessary for the implementation of appropriate control strategies.

  13. Ingested human insulin inhibits the mosquito NF-¿B-dependent immune response to Plasmodium falciparum

    Science.gov (United States)

    We showed previously that ingested human insulin activates the insulin/IGF-1 signaling pathway in Anopheles stephensi and increases the susceptibility of these mosquitoes to Plasmodium falciparum. In other organisms insulin can alter immune responsiveness through regulation of NF-kB transcription fa...

  14. An Epithelial Serine Protease, AgESP, Is Required for Plasmodium Invasion in the Mosquito Anopheles gambiae

    OpenAIRE

    Rodrigues, Janneth; Oliveira, Giselle A.; Kotsyfakis, Michalis; Dixit, Rajnikant; Molina-Cruz, Alvaro; Jochim, Ryan; Barillas-Mury, Carolina

    2012-01-01

    Background Plasmodium parasites need to cross the midgut and salivary gland epithelia to complete their life cycle in the mosquito. However, our understanding of the molecular mechanism and the mosquito genes that participate in this process is still very limited. Methodology/Principal Findings We identified an Anopheles gambiae epithelial serine protease (AgESP) that is constitutively expressed in the submicrovillar region of mosquito midgut epithelial cells and in the basal side of the sali...

  15. Identification of four evolutionarily related G protein-coupled receptors from the malaria mosquito Anopheles gambiae

    DEFF Research Database (Denmark)

    Belmont, Martin; Cazzamali, Giuseppe; Williamson, Michael;

    2006-01-01

    The mosquito Anopheles gambiae is an important vector for malaria, which is one of the most serious human parasitic diseases in the world, causing up to 2.7 million deaths yearly. To contribute to our understanding of A. gambiae and to the transmission of malaria, we have now cloned four evolutio......The mosquito Anopheles gambiae is an important vector for malaria, which is one of the most serious human parasitic diseases in the world, causing up to 2.7 million deaths yearly. To contribute to our understanding of A. gambiae and to the transmission of malaria, we have now cloned four...... evolutionarily related G protein-coupled receptors (GPCRs) from this mosquito and expressed them in Chinese hamster ovary cells. After screening of a library of thirty-three insect or other invertebrate neuropeptides and eight biogenic amines, we could identify (de-orphanize) three of these GPCRs as...... relationship to the A. gambiae and other insect AKH receptors suggested that it is a receptor for an AKH-like peptide. This is the first published report on evolutionarily related AKH, corazonin, and CCAP receptors in mosquitoes....

  16. Mosquito species geographical distribution in Iraq 2009

    Directory of Open Access Journals (Sweden)

    Haidar A. Hantosh, Hameeda M. Hassan, Bushra Ahma & Ali Al-fatlawy

    2012-03-01

    Full Text Available Background & objectives: Mosquitoes transmit diseases to >700 million people annually. Malaria kills threemillion persons every year, including one child every 30 sec. Worldwide there are >3000 mosquito species.In Iraq, 37 species have been identified in different surveys over several decades. We conducted an entomologicalsurvey to determine the mosquito species and their distribution in Iraq in 2009.Methods: Between January 20 and December 31, 2009, mosquitoes in houses in 12 Iraqi provinces werecollected and speciated. Five to 10 villages were selected randomly in each province and in each village 10houses were selected randomly to collect mosquitoes and the density of mosquitoes per room was calculated.Kits for entomological investigation were used and the collected mosquitoes were sent to the vector bornedisease section laboratory for classification using the Naval Medical Research Unit 3 standard classificationkey.Results: A total of 29,156 mosquitoes were collected, representing two genera: Anopheles (n=13,268, or 46%of the total collected and Culex (n=15,888, or 54% of the total collected. Four Anopheles (An. pulcherrimus,An. stephensi, An. superpictus, and An. sacharovi and one Culex (Cx. pipiens species were identified. Anophelespulcherrimus was found in 11 provinces, An. stephensi in 7, An. superpictus in 2 and An. sacharovi in oneprovince, while Cx. pipiens was found in all the 12 provinces. Two peaks of mosquito density were found: thefirst from April–June and the other from September–October.Interpretation & conclusion: There are clear differences in Anopheles mosquito species geographical distributionand density among Iraqi provinces, while Cx. pipiens mosquitoes are distributed all over Iraq. All mosquitogenera show clear seasonal density variation. The study highlights that the manual mosquito classification isnot enough to identify all the species of mosquitoes in Iraq

  17. Unassisted isolated-pair mating of Anopheles gambiae (Diptera: Culicidae) mosquitoes.

    Science.gov (United States)

    Benedict, Mark Q; Rafferty, Cristina S

    2002-11-01

    Female Anopheles mosquitoes usually mate only once, but mating is seldom seen in small containers containing only one female and male. Therefore, matings are often performed among many adults in large cages or by forced copulation. Isolated-pair mating of Anopheles gambiae G3 strain-derived mosquitoes without forced copulation in small vials is described. We observed that the experimental variables eye color and male number were significant factors in the mating frequency. Females mated more frequently when three males were present over only one male. White-eyed females were more likely to be mated than wild-eyed females, but wild males mated more frequently than did white-eyed males. Experiments were also conducted to determine when mating was occurring by using wild-eye-color mosquitoes in isolated pairs. Almost no matings were observed before day 6 rather than the frequencies typically observed after 1-2 d in standard large-cage matings among large numbers of adults.

  18. Disección de mosquitos anopheles (resumen de resultados)

    OpenAIRE

    Cadena, M. A.

    2012-01-01

    Hago a continuación un resumen de los resultados obtenidos con la disección de hembras de anofelinos llevada a cabo en varios sitios del Rio Magdalena y en dos Municipios del Departamento del Valle del Cauca, en los años de 1932 a 1937, figurando en él, el número de disecciones hechas en cada lugar, las especies de anofelinos y lo que en los estómagos y las glándulas salivales de los mosquitos se encontró.

  19. Does polyandrous impede mosquito control by autocidal?

    OpenAIRE

    Jayaprakash, K.; Karthikeyan, V.

    2014-01-01

    Vector mosquito control by releasing genetically altered males has been attempted under the presumption that the females are monandrous. The present observation was through the sex–linked inheritance pattern of eye-colour and the estimation of polyandrous in in-vitro mating. A small proportion (18.2%) of the female Anopheles stephensi population exhibited polyandrous on examination of 850 F1 adults when two types of males (white and black eyed) where allowed to mate with homozygous white eyed...

  20. Comprehensive genetic dissection of the hemocyte immune response in the malaria mosquito Anopheles gambiae.

    Directory of Open Access Journals (Sweden)

    Fabrizio Lombardo

    2013-01-01

    Full Text Available Reverse genetics in the mosquito Anopheles gambiae by RNAi mediated gene silencing has led in recent years to an advanced understanding of the mosquito immune response against infections with bacteria and malaria parasites. We developed RNAi screens in An. gambiae hemocyte-like cells using a library of double-stranded RNAs targeting 109 genes expressed highly or specifically in mosquito hemocytes to identify novel regulators of the hemocyte immune response. Assays included phagocytosis of bacterial bioparticles, expression of the antimicrobial peptide CEC1, and basal and induced expression of the mosquito complement factor LRIM1. A cell viability screen was also carried out to assess dsRNA cytotoxicity and to identify genes involved in cell growth and survival. Our results identify 22 novel immune regulators, including proteins putatively involved in phagosome assembly and maturation (Ca²⁺ channel, v-ATPase and cyclin-dependent protein kinase, pattern recognition (fibrinogen-domain lectins and Nimrod, immune modulation (peptidase and serine protease homolog, immune signaling (Eiger and LPS-induced factor, cell adhesion and communication (Laminin B1 and Ninjurin and immune homeostasis (Lipophorin receptor. The development of robust functional cell-based assays paves the way for genome-wide functional screens to study the mosquito immune response to infections with human pathogens.

  1. Gene expression patterns associated with blood-feeding in the malaria mosquito Anopheles gambiae

    Directory of Open Access Journals (Sweden)

    Hogan James R

    2005-01-01

    Full Text Available Abstract Background Blood feeding, or hematophagy, is a behavior exhibited by female mosquitoes required both for reproduction and for transmission of pathogens. We determined the expression patterns of 3,068 ESTs, representing ~2,000 unique gene transcripts using cDNA microarrays in adult female Anopheles gambiae at selected times during the first two days following blood ingestion, at 5 and 30 min during a 40 minute blood meal and at 0, 1, 3, 5, 12, 16, 24 and 48 hours after completion of the blood meal and compared their expression to transcript levels in mosquitoes with access only to a sugar solution. Results In blood-fed mosquitoes, 413 unique transcripts, approximately 25% of the total, were expressed at least two-fold above or below their levels in the sugar-fed mosquitoes, at one or more time points. These differentially expressed gene products were clustered using k-means clustering into Early Genes, Middle Genes, and Late Genes, containing 144, 130, and 139 unique transcripts, respectively. Several genes from each group were analyzed by quantitative real-time PCR in order to validate the microarray results. Conclusion The expression patterns and annotation of the genes in these three groups (Early, Middle, and Late genes are discussed in the context of female mosquitoes' physiological responses to blood feeding, including blood digestion, peritrophic matrix formation, egg development, and immunity.

  2. Gene expression patterns associated with blood-feeding in the malaria mosquito Anopheles gambiae

    OpenAIRE

    Hogan James R; Lobo Neil F; Harker Brent W; Hillenmeyer Maureen E; Kern Marcia K; Hong Young S; Dana Ali N; Romans Patricia; Collins Frank H

    2005-01-01

    Abstract Background Blood feeding, or hematophagy, is a behavior exhibited by female mosquitoes required both for reproduction and for transmission of pathogens. We determined the expression patterns of 3,068 ESTs, representing ~2,000 unique gene transcripts using cDNA microarrays in adult female Anopheles gambiae at selected times during the first two days following blood ingestion, at 5 and 30 min during a 40 minute blood meal and at 0, 1, 3, 5, 12, 16, 24 and 48 hours after completion of t...

  3. Development of sporogonic cycle of Plasmodium vivax in experimentally infected Anopheles albimanus mosquitoes

    Directory of Open Access Journals (Sweden)

    Martha L. Salas

    1994-01-01

    Full Text Available The sporogonic cycle of Plasmodium vivax was established and maintained under laboratory conditions in two different strains of Anopheles albimanus mosquitoes using as a parasite source blood from human patients or from Aotus monkeys infected with the VCC-2 P.vivax colombian isolate. Both the Tecojate strain isolate from Guatemala and the Cartagena strain from the colombian Pacific coast were susceptible to infections with P.vivax. A higher percentage of Cartagena mosquitoes was infected per trial, however the Tecojate strain developed higher sporozoite loads. Intravenous inoculation of Aotus monkeys with sporozoites obtained from both anopheline strains resulted in successful blood infections. Animals infected with sporozoites from the Tecojate strain presented a patent period of 21-32 days whereas parasitemia appeared between days 19-53 in monkeys infected with sporozites from Cartagena strain.

  4. Development of sporogonic cycle of Plasmodium vivax in experimentally infected Anopheles albimanus mosquitoes.

    Science.gov (United States)

    Salas, M L; Romero, J F; Solarte, Y; Olano, V; Herrera, M A; Herrera, S

    1994-01-01

    The sporogonic cycle of Plasmodium vivax was established and maintained under laboratory conditions in two different strains of Anopheles albimanus mosquitoes using as a parasite source blood from human patients or from Aotus monkeys infected with the VCC-2 P.vivax colombian isolate. Both the Tecojate strain isolate from Guatemala and the Cartagena strain from the colombian Pacific coast were susceptible to infections with P.vivax. A higher percentage of Cartagena mosquitoes was infected per trial, however the Tecojate strain developed higher sporozoite loads. Intravenous inoculation of Aotus monkeys with sporozoites obtained from both anopheline strains resulted in successful blood infections. Animals infected with sporozoites from the Tecojate strain presented a patent period of 21-32 days whereas parasitemia appeared between days 19-53 in monkeys infected with sporozites from Cartagena strain. PMID:7565121

  5. Identification of a Bacillus thuringiensis Cry11Ba toxin-binding aminopeptidase from the mosquito, Anopheles quadrimaculatus

    Directory of Open Access Journals (Sweden)

    Abdullah Mohd

    2006-05-01

    Full Text Available Abstract Background Aminopeptidase N (APN type proteins isolated from several species of lepidopteran insects have been implicated as Bacillus thuringiensis (Bt toxin-binding proteins (receptors for Cry toxins. We examined brush border membrane vesicle (BBMV proteins from the mosquito Anopheles quadrimaculatus to determine if APNs from this organism would bind mosquitocidal Cry toxins that are active to it. Results A 100-kDa protein with APN activity (APNAnq 100 was isolated from the brush border membrane of Anopheles quadrimaculatus. Native state binding analysis by surface plasmon resonance shows that APNAnq 100 forms tight binding to a mosquitocidal Bt toxin, Cry11Ba, but not to Cry2Aa, Cry4Ba or Cry11Aa. Conclusion An aminopeptidase from Anopheles quadrimaculatus mosquitoes is a specific binding protein for Bacillus thuringiensis Cry11Ba.

  6. Synergism between ammonia, lactic acid and carboxylic acids as kairomones in the host-seeking behaviour of the malaria mosquito Anopheles gambiae sensu stricto (Diptera: Culicidae)

    NARCIS (Netherlands)

    Smallegange, R.C.; Qiu, Y.T.; Loon, van J.J.A.; Takken, W.

    2005-01-01

    Host odours play a major role in the orientation and host location of blood-feeding mosquitoes. Anopheles gambiae Giles sensu stricto, which is the most important malaria vector in Africa, is a highly anthropophilic mosquito species, and the host-seeking behaviour of the females of this mosquito is

  7. Some strains of Plasmodium falciparum, a human malaria parasite, evade the complement-like system of Anopheles gambiae mosquitoes

    OpenAIRE

    Molina-Cruz, Alvaro; DeJong, Randall J.; Ortega, Corrie; Haile, Ashley; Abban, Ekua; Rodrigues, Janneth; Jaramillo-Gutierrez, Giovanna; Barillas-Mury, Carolina

    2012-01-01

    Plasmodium falciparum lines differ in their ability to infect mosquitoes. The Anopheles gambiae L3-5 refractory (R) line melanizes most Plasmodium species, including the Brazilian P. falciparum 7G8 line, but it is highly susceptible to some African P. falciparum strains such as 3D7, NF54, and GB4. We investigated whether these lines differ in their ability to evade the mosquito immune system. Silencing key components of the mosquito complement-like system [thioester-containing protein 1 (TEP1...

  8. Maternal environment shapes the life history and susceptibility to malaria of Anopheles gambiae mosquitoes

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    Lorenz Lena M

    2011-12-01

    Full Text Available Abstract Background It is becoming generally recognized that an individual's phenotype can be shaped not only by its own genotype and environmental experience, but also by its mother's environment and condition. Maternal environmental factors can influence mosquitoes' population dynamics and susceptibility to malaria, and therefore directly and indirectly the epidemiology of malaria. Methods In a full factorial experiment, the effects of two environmental stressors - food availability and infection with the microsporidian parasite Vavraia culicis - of female mosquitoes (Anopheles gambiae sensu stricto on their offspring's development, survival and susceptibility to malaria were studied. Results The offspring of A. gambiae s.s. mothers infected with V. culicis developed into adults more slowly than those of uninfected mothers. This effect was exacerbated when mothers were reared on low food. Maternal food availability had no effect on the survival of their offspring up to emergence, and microsporidian infection decreased survival only slightly. Low food availability for mothers increased and V. culicis-infection of mothers decreased the likelihood that the offspring fed on malaria-infected blood harboured malaria parasites (but neither maternal treatment influenced their survival up to dissection. Conclusions Resource availability and infection with V. culicis of A. gambiae s.s. mosquitoes not only acted as direct environmental stimuli for changes in the success of one generation, but could also lead to maternal effects. Maternal V. culicis infection could make offspring more resistant and less likely to transmit malaria, thus enhancing the efficacy of the microsporidian for the biological control of malaria.

  9. The STAT pathway mediates late phase immunity against Plasmodium in the mosquito Anopheles gambiae

    Science.gov (United States)

    Gupta, Lalita; Molina-Cruz, Alvaro; Kumar, Sanjeev; Rodrigues, Janneth; Dixit, Rajnikant; Zamora, Rodolfo E.; Barillas-Mury, Carolina

    2009-01-01

    The STAT family of transcription factors activate expression of immune system genes in vertebrates. The ancestral STAT gene (AgSTAT-A) appears to have duplicated in the mosquito Anopheles gambiae, giving rise to a second intronless STAT gene (AgSTAT-B), which we show regulates AgSTAT-A expression in adult females. AgSTAT-A participates in the transcriptional activation of nitric oxide synthase (NOS) in response to bacterial and plasmodial infection. Activation of this pathway, however, is not essential for mosquitoes to survive a bacterial challenge. AgSTAT-A silencing reduces the number of early Plasmodium oocysts in the midgut, but nevertheless enhances the overall infection by increasing oocyst survival. Silencing of SOCS, a STAT suppressor, has the opposite effect, reducing Plasmodium infection by increasing NOS expression. Chemical inhibition of mosquito NOS activity after oocyte formation increases oocyte survival. Thus, the AgSTAT-A pathway mediates a late phase anti-plasmodial response that reduces oocyst survival in An. gambiae. PMID:19454353

  10. The STAT pathway mediates late-phase immunity against Plasmodium in the mosquito Anopheles gambiae.

    Science.gov (United States)

    Gupta, Lalita; Molina-Cruz, Alvaro; Kumar, Sanjeev; Rodrigues, Janneth; Dixit, Rajnikant; Zamora, Rodolfo E; Barillas-Mury, Carolina

    2009-05-01

    The STAT family of transcription factors activates expression of immune system genes in vertebrates. The ancestral STAT gene (AgSTAT-A) appears to have duplicated in the mosquito Anopheles gambiae, giving rise to a second intronless STAT gene (AgSTAT-B), which we show regulates AgSTAT-A expression in adult females. AgSTAT-A participates in the transcriptional activation of nitric oxide synthase (NOS) in response to bacterial and plasmodial infection. Activation of this pathway, however, is not essential for mosquitoes to survive a bacterial challenge. AgSTAT-A silencing reduces the number of early Plasmodium oocysts in the midgut, but nevertheless enhances the overall infection by increasing oocyst survival. Silencing of SOCS, a STAT suppressor, has the opposite effect, reducing Plasmodium infection by increasing NOS expression. Chemical inhibition of mosquito NOS activity after oocyte formation increases oocyte survival. Thus, the AgSTAT-A pathway mediates a late-phase antiplasmodial response that reduces oocyst survival in A. gambiae. PMID:19454353

  11. Anopheles salivary gland proteomes from major malaria vectors

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    Fontaine Albin

    2012-11-01

    Full Text Available Abstract Background Antibody responses against Anopheles salivary proteins can indicate individual exposure to bites of malaria vectors. The extent to which these salivary proteins are species-specific is not entirely resolved. Thus, a better knowledge of the diversity among salivary protein repertoires from various malaria vector species is necessary to select relevant genus-, subgenus- and/or species-specific salivary antigens. Such antigens could be used for quantitative (mosquito density and qualitative (mosquito species immunological evaluation of malaria vectors/host contact. In this study, salivary gland protein repertoires (sialomes from several Anopheles species were compared using in silico analysis and proteomics. The antigenic diversity of salivary gland proteins among different Anopheles species was also examined. Results In silico analysis of secreted salivary gland protein sequences retrieved from an NCBInr database of six Anopheles species belonging to the Cellia subgenus (An. gambiae, An. arabiensis, An. stephensi and An. funestus and Nyssorhynchus subgenus (An. albimanus and An. darlingi displayed a higher degree of similarity compared to salivary proteins from closely related Anopheles species. Additionally, computational hierarchical clustering allowed identification of genus-, subgenus- and species-specific salivary proteins. Proteomic and immunoblot analyses performed on salivary gland extracts from four Anopheles species (An. gambiae, An. arabiensis, An. stephensi and An. albimanus indicated that heterogeneity of the salivary proteome and antigenic proteins was lower among closely related anopheline species and increased with phylogenetic distance. Conclusion This is the first report on the diversity of the salivary protein repertoire among species from the Anopheles genus at the protein level. This work demonstrates that a molecular diversity is exhibited among salivary proteins from closely related species despite their

  12. A Study of the Essential Oils of Four Sudanese Accessions of Basil (Ocimum basilicum L. Against Anopheles Mosquito Larvae

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    Azhari H. Nour

    2009-01-01

    Full Text Available Problem statement: Certain basil essential oils were claimed to have a larvicidal activity towards mosquito's larvae. To test this claim the essential oils of four accessions of basil grown in Sudan were selected and tested for Anopheles larvae. Malaria is the major health problem in the Sudan and the whole country is now considered endemic, with varying degrees, about 35,000 deaths every year due to malaria. Anopheles mosquito is the major vector of malaria disease in Sudan. Search for larvicidal active compound(s is one of several attempts to fine effective and affordable ways to control this mosquito. To determine the toxic effects of basil essential oils extracted by steam distillation against Anopheles larvae. Approach: For the larvicidal bioassay, three concentrations (100, 300, 500 ppm of essential oil solutions of four basil accessions were prepared; 1 mL of ethanol was used to solubilize the oil in water (999 mL. In each concentration of oil solution were inserted 20 larvae (third instars. A set of controls using 0.1% ethanol and untreated sets of larvae in (tap water, were also run for comparison. Data were evaluated through regression analysis, from the regression line; the LC50 values were read. The active ingredients were separated and/ or identified by TLC, IR and GC-MS. Results: Larvicidal activity of the essential oils is varied, lasted for about 9 h and thereafter decreased, LC50 values ranging from 190-300 ppm. Linalool, geraniol and eugenol are active components of basil essential oil against Anopheles larvae. Two accessions were caused 100% mortality at a concentration range 300-500 ppm for 3 h. Conclusion: These results indicated that basil essential oils have larvicidal activity towards Anopheles larvae. Therefore, could be affordable way to control this mosquito.

  13. Energy metabolism affects susceptibility of Anopheles gambiae mosquitoes to Plasmodium infection.

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    Oliveira, Jose Henrique M; Gonçalves, Renata L S; Oliveira, Giselle A; Oliveira, Pedro L; Oliveira, Marcus F; Barillas-Mury, Carolina

    2011-06-01

    Previous studies showed that Anopheles gambiae L3-5 females, which are refractory (R) to Plasmodium infection, express higher levels of genes involved in redox-metabolism and mitochondrial respiration than susceptible (S) G3 females. Our studies revealed that R females have reduced longevity, faster utilization of lipid reserves, impaired mitochondrial state-3 respiration, increased rate of mitochondrial electron leak and higher expression levels of several glycolytic enzyme genes. Furthermore, when state-3 respiration was reduced in S females by silencing expression of the adenine nucleotide translocator (ANT), hydrogen peroxide generation was higher and the mRNA levels of lactate dehydrogenase increased in the midgut, while the prevalence and intensity of Plasmodium berghei infection were significantly reduced. We conclude that there are broad metabolic differences between R and S An. gambiae mosquitoes that influence their susceptibility to Plasmodium infection. PMID:21320598

  14. Random amplified polymorphic DNA (RAPD) markers readily distinguish cryptic mosquito species (Diptera: Culicidae: Anopheles).

    Science.gov (United States)

    Wilkerson, R C; Parsons, T J; Albright, D G; Klein, T A; Braun, M J

    1993-01-01

    The usefulness of random amplified polymorphic DNA (RAPD) was examined as a potential tool to differentiate cryptic mosquito species. It proved to be a quick, effective means of finding genetic markers to separate two laboratory populations of morphologically indistinguishable African malaria vectors, Anopheles gambiae and An. arabiensis. In an initial screening of fifty-seven RAPD primers, 377 bands were produced, 295 of which differed between the two species. Based on criteria of interpretability, simplicity and reproducibility, thirteen primers were chosen for further screening using DNA from thirty individuals of each species. Seven primers produced diagnostic bands, five of which are described here. Some problematic characteristics of RAPD banding patterns are discussed and approaches to overcome these are suggested. PMID:8269099

  15. The role of cow urine in the oviposition site preference of culicine and Anopheles mosquitoes

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    Kweka Eliningaya J

    2011-09-01

    Full Text Available Abstract Background Chemical and behavioural ecology of mosquitoes plays an important role in the development of chemical cue based vector control. To date, studies available have focused on evaluating mosquito attractants and repellents of synthetic and human origins. This study, however, was aimed at seasonal evaluation of the efficiency of cow urine in producing oviposition cues to Anopheles gambiae s.l. and Culex quinquefasciatus in both laboratory and field conditions. Methods Oviposition response evaluation in laboratory conditions was carried out in mosquito rearing cages. The oviposition substrates were located in parallel or in diagonal positions inside the cage. Urine evaluation against gravid females of An. arabiensis and Cx. quinquefasciatus was carried out at Day 1, Day 3 and Day 7. Five millilitres (mls of cow urine was added to oviposition substrate while de-chlorinated water was used as a control. In field experiments, 500 mls of cow urine was added in artificial habitats with 2500 mls of de-chlorinated water and 2 kgs of soil. The experiment was monitored for thirty consecutive days, eggs were collected daily from the habitats at 7.00 hrs. Data analysis was performed using parametric and non-parametric tests for treatments and controls while attraction of the oviposition substrate in each species was presented using Oviposition Activity Index (OAI. Results The OAI was positive with ageing of cattle urine in culicine species in both laboratory and field experiments. The OAI for anopheline species was positive with fresh urine. The OAI during the rainy season was positive for all species tested while in the dry season the OAI for culicine spp and Anopheles gambiae s.l., changed with time from positive to negative values. Based on linear model analysis, seasons and treatments had a significant effect on the number of eggs laid in habitats, even though the number of days had no effect. Conclusion Oviposition substrates treated with

  16. Spermless males elicit large-scale female responses to mating in the malaria mosquito Anopheles gambiae

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    Thailayil, Janis; Magnusson, Kalle; Godfray, H. Charles J.; Crisanti, Andrea; Catteruccia, Flaminia

    2011-01-01

    Anopheles gambiae sensu stricto is the major vector of malaria, a disease with devastating consequences for human health. Given the constant spread of the disease, alternative approaches to the use of insecticides are urgently needed to control vector populations. Females of this species undergo large behavioral changes after mating, which include a life-long refractoriness to further insemination and the induction of egg laying in blood-fed individuals. Genetic control strategies aimed at impacting Anopheles fertility through the release of sterile males are being advocated to reduce the size of mosquito field populations. Such strategies depend on the ability of the released sterile males to mate successfully with wild females and to switch off the female receptivity to further copulation. Here we evaluate the role of sperm in regulating female behavioral responses after mating in An. gambiae. We developed spermless males by RNAi silencing of a germ cell differentiation gene. These males mated successfully and preserved standard accessory gland functions. Females mated to spermless males exhibited normal postcopulatory responses, which included laying large numbers of eggs upon blood feeding and becoming refractory to subsequent insemination. Moreover, spermless males induced transcriptional changes in female reproductive genes comparable to those elicited by fertile males. Our data demonstrate that, in contrast to Drosophila, targeting sperm in An. gambiae preserves normal male and female reproductive behavior for the traits and time frame analyzed and validate the use of approaches based on incapacitation or elimination of sperm for genetic control of vector populations to block malaria transmission. PMID:21825136

  17. Radiation-induced sterility for pupal and adult stages of the malaria mosquito Anopheles arabiensis

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    Knols Bart GJ

    2006-05-01

    Full Text Available Abstract Background In the context of the Sterile Insect Technique (SIT, radiation-induced sterility in the malaria mosquito Anopheles arabiensis Patton (Diptera: Culicidae was studied. Male mosquitoes were exposed to gamma rays in the pupal or adult stage and dose-sterility curves were determined. Methods Pupae were irradiated shortly before emergence (at 22–26 hrs of age, and adults Results Irradiation of pupae, for all doses tested, had no effect on adult emergence. Survival curves of males irradiated as pupae or adults were similar or even slightly higher than non-irradiated males. Overall, adults appeared to be slightly more susceptible to irradiation, although no significant differences for individual doses were observed. In the pupal stage, a significant negative correlation was found between insemination and dose, but the correlation-coefficient was associated with less than 25% of the total variation. A review of the literature indicated that An. arabiensis is more radiation resistant than other anopheline mosquitoes. Conclusion The optimal dose for male insects to be released in an SIT programme depends on their level of sterility and competitiveness. The use of semi-sterilizing doses to produce more competitive insects is discussed. The most convenient developmental stage for mosquito irradiation on a mass-scale are pupae, but pupal irradiation resulted in a lower insemination rate at the highest dose compared to adult irradiation. On the basis of this study, a suitable dose range that includes semi-sterilizing doses is identified to initiate competitiveness experiments for males irradiated at both developmental stages.

  18. Genotyping of chloroquine resistant Plasmodium falciparum in wild caught Anopheles minimus mosquitoes in a malaria endemic area of Assam, India.

    Science.gov (United States)

    Sarma, D K; Mohapatra, P K; Bhattacharyya, D R; Mahanta, J; Prakash, A

    2014-09-01

    We validated the feasibility of using Plasmodium falciparum, the human malaria parasite, DNA present in wild caught vector mosquitoes for the characterization of chloroquine resistance status. House frequenting mosquitoes belonging to Anopheles minimus complex were collected from human dwellings in a malaria endemic area of Assam, Northeast India and DNA was extracted from the head-thorax region of individual mosquitoes. Anopheles minimus complex mosquitoes were identified to species level and screened for the presence of Plasmodium sp. using molecular tools. Nested PCR-RFLP method was used for genotyping of P. falciparum based on K76T mutation in the chloroquine resistance transporter (pfcrt) gene. Three of the 27 wild caught An. minimus mosquitoes were harbouring P. falciparum sporozoites (positivity 11.1%) and all 3 were had 76T mutation in the pfcrt gene, indicating chloroquine resistance. The approach of characterizing antimalarial resistance of malaria parasite in vector mosquitoes can potentially be used as a surveillance tool for monitoring transmission of antimalarial drug resistant parasite strains in the community.

  19. Using green fluorescent malaria parasites to screen for permissive vector mosquitoes

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    Martin Beatrice

    2006-03-01

    Full Text Available Abstract Background The Plasmodium species that infect rodents, particularly Plasmodium berghei and Plasmodium yoelii, are useful to investigate host-parasite interactions. The mosquito species that act as vectors of human plasmodia in South East Asia, Africa and South America show different susceptibilities to infection by rodent Plasmodium species. P. berghei and P. yoelii infect both Anopheles gambiae and Anopheles stephensi, which are found mainly in Africa and Asia, respectively. However, it was reported that P. yoelii can infect the South American mosquito, Anopheles albimanus, while P. berghei cannot. Methods P. berghei lines that express the green fluorescent protein were used to screen for mosquitoes that are susceptible to infection by P. berghei. Live mosquitoes were examined and screened for the presence of a fluorescent signal in the abdomen. Infected mosquitoes were then examined by time-lapse microscopy to reveal the dynamic behaviour of sporozoites in haemolymph and extracted salivary glands. Results A single fluorescent oocyst can be detected in live mosquitoes and P. berghei can infect A. albimanus. As in other mosquitoes, P. berghei sporozoites can float through the haemolymph and invade A. albimanus salivary glands and they are infectious in mice after subcutaneous injection. Conclusion Fluorescent Plasmodium parasites can be used to rapidly screen susceptible mosquitoes. These results open the way to develop a laboratory model in countries where importation of A. gambiae and A. stephensi is not allowed.

  20. Screening of selected ethnomedicinal plants from South Africa for larvicidal activity against the mosquito Anopheles arabiensis

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    Maharaj Rajendra

    2012-09-01

    Full Text Available Abstract Background This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic, that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito larvicidal properties. Methods Extracts of a selection of plant taxa sourced in South Africa were tested for larvicidal properties in an applicable assay. Thirty 3rd instar Anopheles arabiensis larvae were exposed to various extract types (dichloromethane, dichloromethane/methanol (1:1, methanol and purified water of each species investigated. Mortality was evaluated relative to the positive control Temephos (Mostop; Agrivo, an effective emulsifiable concentrate larvicide. Results Preliminary screening of crude extracts revealed substantial variation in toxicity with 24 of the 381 samples displaying 100% larval mortality within the seven day exposure period. Four of the high activity plants were selected and subjected to bioassay guided fractionation. The results of the testing of the fractions generated identified one fraction of the plant, Toddalia asiatica as being very potent against the An. arabiensis larvae. Conclusion The present study has successfully identified a plant with superior larvicidal activity at both the crude and semi pure fractions generated through bio-assay guided fractionation. These results have initiated further research into isolating the active compound and developing a malaria vector control tool.

  1. A possible mechanism for the suppression of Plasmodium berghei development in the mosquito Anopheles gambiae by the microsporidian Vavraia culicis.

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    Irka Bargielowski

    Full Text Available BACKGROUND: Microsporidian parasites of mosquitoes offer a possible way of controlling malaria, as they impede the development of Plasmodium parasites within the mosquito. The mechanism involved in this interference process is unknown. METHODOLOGY: We evaluated the possibility that larval infection by a microsporidian primes the immune system of adult mosquitoes in a way that enables a more effective anti-Plasmodium response. To do so, we infected 2-day old larvae of the mosquito Anopheles gambiae with one of 4 isolates of the microsporidian Vavraia culicis and reared one group as an uninfected control. Within each treatment, we fed half the adult females on a mix of P. berghei ookinetes and blood and inoculated the other half with a negatively charged CM-25 Sephadex bead to evaluate the mosquitoes' melanisation response. CONCLUSIONS: The microsporidian-infected mosquitoes were less likely to harbour oocysts (58.5% vs. 81.8%, harboured fewer oocysts (8.9 oocysts vs. 20.7 oocysts if the malaria parasite did develop and melanised the Sephadex bead to a greater degree (73% vs. 35% than the controls. While the isolates differed in the number of oocysts and in the melanisation response, the stimulation of the immune response was not correlated with either measure of malaria development. Nevertheless, the consistent difference between microsporidian-infected and -uninfected mosquitoes--more effective melanisation and less successful infection by malaria--suggests that microsporidians impede the development of malaria by priming the mosquito's immune system.

  2. Feeding and indoor resting behaviour of the mosquito Anopheles longipalpis in an area of hyperendemic malaria transmission in southern Zambia

    OpenAIRE

    Kent, R.J.; Coetzee, M.; Mharakurwa, S.; Norris, D. E.

    2006-01-01

    Anopheles longipalpis (Theobald) (Diptera: Culicidae) is a predominantly zoophilic mosquito that has not been implicated in malaria transmission. However, this species was collected indoors with An. funestus s.l. in southern Zambia, where transmission of Plasmodium falciparum is hyperendemic, and we initially misidentified it morphologically and molecularly as An. funestus s.l. The indoor resting density and blood-feeding behaviour of An. longipalpis were investigated during the 2004 – 05 and...

  3. Effects of blood-feeding on olfactory sensitivity of the malaria mosquito Anopheles gambiae: application of mixed linear models to account for repeated measurements

    NARCIS (Netherlands)

    Qiu, Y.T.; Gort, G.; Torricelli, A.; Takken, W.; Loon, van J.J.A.

    2013-01-01

    Olfaction plays an important role in the host-seeking behavior of the malaria mosquito Anopheles gambiae. After a complete blood meal, female mosquitoes will not engage in host-seeking behavior until oviposition has occurred. We investigated if peripheral olfactory sensitivity changed after a blood

  4. Life-table analysis of Anopheles malaria vectors: generational mortality as tool in mosquito vector abundance and control studies

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    Godwin Ray Anugboba Okogun

    2005-06-01

    Full Text Available Background & objectives: Vector control will for sometime remain a primary weapon in the waragainst vector borne diseases. Malaria is of paramount importance in this with its associated highmorbidity and mortality especially in sub-Saharan Africa. This study on generational mortality associatedfactors in Anopheles mosquitoes life-table analysis was designed to investigate the fecundity,levels of mortality and mortality associated factors at the aquatic stages of anopheline malaria vectors.Methods: Mortality associated factors were investigated at the eggs, I and II instar larval, III and IVinstar larval and pupal stages of two anopheline species— Anopheles pseudopunctipennis (Theobaldand An. gambiae life-cycles in screen cages. Adult male and female mosquitoes were membrane filterfedand algae in culture medium formed the bulk of food substances for the larval stage. Environmentaltemperature of culture media, pH and some associated physio-chemical factors were also determined.Results: Results showed significant mortality rates at various aquatic stages. Infertility, cannibalismand environmental factors were the major factors responsible for mortality at the egg, larval and pupalstages respectively.Interpretation & conclusion: The aquatic stages of Anopheles mosquito mortality factor K and themortality factors at the various stages investigated k1, k2, k3 and k4 are discussed. Our recommendationsinclude further studies on the possible genetic modification of predacious An. pseudopunctipennislarvae and/or its modification for the production of sterile/infertile eggs as possible alternativesin the reduction and control of anopheline malaria burden.

  5. Identification of the midgut microbiota of An. stephensi and An. maculipennis for their application as a paratransgenic tool against malaria.

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    Navid Dinparast Djadid

    Full Text Available The midgut microbiota associated with Anopheles stephensi and Anopheles maculipennis (Diptera: Culicidae was investigated for development of a paratransgenesis-based approach to control malaria transmission in Eastern Mediterranean Region (EMR. Here, we present the results of a polymerase chain reaction (PCR and biochemical-based approaches to identify the female adult and larvae mosquitoe microbiota of these two major malaria vectors, originated from South Eastern and North of Iran. Plating the mosquito midgut contents from lab-reared and field-collected Anopheles spp. was used for microbiota isolation. The gram-negative and gram-positive bacterial colonies were identified by Gram staining and specific mediums. Selected colonies were identified by differential biochemical tests and 16S rRNA gene sequence analysis. A number of 10 An. stephensi and 32 An. maculipennis adult mosquitoes and 15 An. stephensi and 7 An. maculipennis larvae were analyzed and 13 sequences of 16S rRNA gene bacterial species were retrieved, that were categorized in 3 classes and 8 families. The majority of the identified bacteria were belonged to the γ-proteobacteria class, including Pseudomonas sp. and Aeromonas sp. and the others were some closely related to those found in other vector mosquitoes, including Pantoea, Acinetobacter, Brevundimonas, Bacillus, Sphingomonas, Lysinibacillus and Rahnella. The 16S rRNA sequences in the current study aligned with the reference strains available in GenBank were used for construction of the phylogenetic tree that revealed the relatedness among the bacteria identified. The presented data strongly encourage further investigations, to verify the potential role of the detected bacteria for the malaria control in Iran and neighboring countries.

  6. Attractiveness of volatiles from different body parts to the malaria mosquito Anopheles coluzzii is affected by deodorant compounds.

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    Verhulst, Niels O; Weldegergis, Berhane T; Menger, David; Takken, Willem

    2016-01-01

    Mosquitoes display biting preferences among different sites of the human body. In addition to height or convection currents, body odour may play a role in the selection of these biting sites. Previous studies have shown that skin emanations are important host-finding cues for mosquitoes. In this study, skin emanations were collected from armpits, hands and feet; the volatile profiles were analysed and tested for their attractiveness to the malaria mosquito Anopheles coluzzii. Skin emanations collected from armpits were less attractive to An. coluzzii compared to hands or/and feet. The difference may have been caused by deodorant residues, which were found in the armpit samples and not in those of hands and feet. In a subsequent experiment, volunteers were asked to avoid using skincare products for five days, and thereafter, no differences in attractiveness of the body parts to mosquitoes were found. The detected deodorant compound isopropyl tetradecanoate inhibited mosquito landings in a repellent bioassay. It is concluded that the volatiles emanated from different body parts induced comparable levels of attraction in mosquitoes, and that skincare products may reduce a person's attractiveness to mosquitoes. PMID:27251017

  7. Attractiveness of volatiles from different body parts to the malaria mosquito Anopheles coluzzii is affected by deodorant compounds.

    Science.gov (United States)

    Verhulst, Niels O; Weldegergis, Berhane T; Menger, David; Takken, Willem

    2016-06-01

    Mosquitoes display biting preferences among different sites of the human body. In addition to height or convection currents, body odour may play a role in the selection of these biting sites. Previous studies have shown that skin emanations are important host-finding cues for mosquitoes. In this study, skin emanations were collected from armpits, hands and feet; the volatile profiles were analysed and tested for their attractiveness to the malaria mosquito Anopheles coluzzii. Skin emanations collected from armpits were less attractive to An. coluzzii compared to hands or/and feet. The difference may have been caused by deodorant residues, which were found in the armpit samples and not in those of hands and feet. In a subsequent experiment, volunteers were asked to avoid using skincare products for five days, and thereafter, no differences in attractiveness of the body parts to mosquitoes were found. The detected deodorant compound isopropyl tetradecanoate inhibited mosquito landings in a repellent bioassay. It is concluded that the volatiles emanated from different body parts induced comparable levels of attraction in mosquitoes, and that skincare products may reduce a person's attractiveness to mosquitoes.

  8. Evaluation of Solanum xanthocarpum extracts as mosquito larvicides.

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    Mohan, Lalit; Sharma, Preeti; Srivastava, C N

    2005-06-01

    Mosquito larvicidal activity of crude carbon-tetra-chloride, methanol and petroleum ether extracts of Solanum xanthocarpum fruits was examined against Anopheles stephensi and Culex quinquefasciatus. Among the extracts tested, carbon-tetra-chloride extract was the most effective with LC50 values of 5.11 ppm after 24 hours and 1.27 ppm after 48 hours of treatment against An. stephensi. In the case of Cx. quinquefasciatus the petroleum ether extract was observed as most toxic with LC50 values of 62.62 ppm after 24 hours and 59.45 ppm after 48 hours of exposure period respectively. It is, therefore, suggested that S. xanthocarpum can be applied as an ideal potential larvicide against An. stephensi and Cx. quinquefasciatus.

  9. Biochemical characterization of Anopheles gambiae SRPN6, a malaria parasite invasion marker in mosquitoes.

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    Chunju An

    Full Text Available Serine proteinase inhibitors of the serpin family are well known as negative regulators of hemostasis, thrombolysis and innate immune responses. Additionally, non-inhibitory serpins serve functions as chaperones, hormone transporters, or anti-angiogenic factors. In the African malaria mosquito, Anopheles gambiae s.s., at least three serpins (SRPNs are implicated in the innate immune response against malaria parasites. Based on reverse genetic and cell biological analyses, AgSRPN6 limits parasite numbers and transmission and has been postulated to control melanization and complement function in mosquitoes. This study aimed to characterize AgSRPN6 biophysically and determine its biochemical mode of action. The structure model of AgSRPN6, as predicted by I-Tasser showed the protein in the native serpin fold, with three central β-sheets, nine surrounding α-helices, and a protruding reactive center loop. This structure is in agreement with biophysical and functional data obtained from recombinant (r AgSRPN6, produced in Escherichia coli. The physical properties of purified rAgSRPN6 were investigated by means of analytical ultracentrifugation, circular dichroism, and differential scanning calorimetry tools. The recombinant protein exists predominantly as a monomer in solution, is composed of a mixture of α-helices and β-sheets, and has a mid-point unfolding temperature of 56°C. Recombinant AgSRPN6 strongly inhibited porcine pancreatic kallikrein and to a lesser extent bovine pancreatic trypsin in vitro. Furthermore, rAgSRPN6 formed inhibitory, SDS-stable, higher molecular weight complexes with prophenoloxidase-activating proteinase (PAP1, PAP3, and Hemolymph protein (HP6, which are required for melanization in the lepidopteran model organism, Manduca sexta. Taken together, our results strongly suggest that AgSRPN6 takes on a native serpin fold and is an inhibitor of trypsin-like serine proteinases.

  10. Biochemical characterization of Anopheles gambiae SRPN6, a malaria parasite invasion marker in mosquitoes.

    Science.gov (United States)

    An, Chunju; Hiromasa, Yasuaki; Zhang, Xin; Lovell, Scott; Zolkiewski, Michal; Tomich, John M; Michel, Kristin

    2012-01-01

    Serine proteinase inhibitors of the serpin family are well known as negative regulators of hemostasis, thrombolysis and innate immune responses. Additionally, non-inhibitory serpins serve functions as chaperones, hormone transporters, or anti-angiogenic factors. In the African malaria mosquito, Anopheles gambiae s.s., at least three serpins (SRPNs) are implicated in the innate immune response against malaria parasites. Based on reverse genetic and cell biological analyses, AgSRPN6 limits parasite numbers and transmission and has been postulated to control melanization and complement function in mosquitoes. This study aimed to characterize AgSRPN6 biophysically and determine its biochemical mode of action. The structure model of AgSRPN6, as predicted by I-Tasser showed the protein in the native serpin fold, with three central β-sheets, nine surrounding α-helices, and a protruding reactive center loop. This structure is in agreement with biophysical and functional data obtained from recombinant (r) AgSRPN6, produced in Escherichia coli. The physical properties of purified rAgSRPN6 were investigated by means of analytical ultracentrifugation, circular dichroism, and differential scanning calorimetry tools. The recombinant protein exists predominantly as a monomer in solution, is composed of a mixture of α-helices and β-sheets, and has a mid-point unfolding temperature of 56°C. Recombinant AgSRPN6 strongly inhibited porcine pancreatic kallikrein and to a lesser extent bovine pancreatic trypsin in vitro. Furthermore, rAgSRPN6 formed inhibitory, SDS-stable, higher molecular weight complexes with prophenoloxidase-activating proteinase (PAP)1, PAP3, and Hemolymph protein (HP)6, which are required for melanization in the lepidopteran model organism, Manduca sexta. Taken together, our results strongly suggest that AgSRPN6 takes on a native serpin fold and is an inhibitor of trypsin-like serine proteinases. PMID:23152794

  11. Identification and analysis of Single Nucleotide Polymorphisms (SNPs in the mosquito Anopheles funestus, malaria vector

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    Hemingway Janet

    2007-01-01

    Full Text Available Abstract Background Single nucleotide polymorphisms (SNPs are the most common source of genetic variation in eukaryotic species and have become an important marker for genetic studies. The mosquito Anopheles funestus is one of the major malaria vectors in Africa and yet, prior to this study, no SNPs have been described for this species. Here we report a genome-wide set of SNP markers for use in genetic studies on this important human disease vector. Results DNA fragments from 50 genes were amplified and sequenced from 21 specimens of An. funestus. A third of specimens were field collected in Malawi, a third from a colony of Mozambican origin and a third form a colony of Angolan origin. A total of 494 SNPs including 303 within the coding regions of genes and 5 indels were identified. The physical positions of these SNPs in the genome are known. There were on average 7 SNPs per kilobase similar to that observed in An. gambiae and Drosophila melanogaster. Transitions outnumbered transversions, at a ratio of 2:1. The increased frequency of transition substitutions in coding regions is likely due to the structure of the genetic code and selective constraints. Synonymous sites within coding regions showed a higher polymorphism rate than non-coding introns or 3' and 5'flanking DNA with most of the substitutions in coding regions being observed at the 3rd codon position. A positive correlation in the level of polymorphism was observed between coding and non-coding regions within a gene. By genotyping a subset of 30 SNPs, we confirmed the validity of the SNPs identified during this study. Conclusion This set of SNP markers represents a useful tool for genetic studies in An. funestus, and will be useful in identifying candidate genes that affect diverse ranges of phenotypes that impact on vector control, such as resistance insecticide, mosquito behavior and vector competence.

  12. Parasite killing in malaria non-vector mosquito Anopheles culicifacies species B: implication of nitric oxide synthase upregulation.

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    Sonam Vijay

    Full Text Available BACKGROUND: Anopheles culicifacies, the main vector of human malaria in rural India, is a complex of five sibling species. Despite being phylogenetically related, a naturally selected subgroup species B of this sibling species complex is found to be a poor vector of malaria. We have attempted to understand the differences between vector and non-vector Anopheles culicifacies mosquitoes in terms of transcriptionally activated nitric oxide synthase (AcNOS physiologies to elucidate the mechanism of refractoriness. Identification of the differences between genes and gene products that may impart refractory phenotype can facilitate development of novel malaria transmission blocking strategies. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a study on phylogenetically related susceptible (species A and refractory (species B sibling species of An. culicifacies mosquitoes to characterize biochemical and molecular differences in AcNOS gene and gene elements and their ability to inhibit oocyst growth. We demonstrate that in species B, AcNOS specific activity and nitrite/nitrates in mid-guts and haemolymph were higher as compared to species A after invasion of the mid-gut by P. vivax at the beginning and during the course of blood feeding. Semiquantitative RT-PCR and real time PCR data of AcNOS concluded that this gene is more abundantly expressed in midgut of species B than in species A and is transcriptionally upregulated post blood meals. Dietary feeding of L-NAME along with blood meals significantly inhibited midgut AcNOS activity leading to an increase in oocyst production in An. culicifacies species B. CONCLUSIONS/SIGNIFICANCE: We hypothesize that upregulation of mosquito innate cytotoxicity due to NOS in refractory strain to Plasmodium vivax infection may contribute to natural refractoriness in An. culicifacies mosquito population. This innate capacity of refractory mosquitoes could represent the ancestral function of the mosquito immune system against

  13. Suboptimal Larval Habitats Modulate Oviposition of the Malaria Vector Mosquito Anopheles coluzzii.

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    Eunho Suh

    Full Text Available 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.

  14. Swarming and mating activity of Anopheles gambiae mosquitoes in semi-field enclosures.

    Science.gov (United States)

    Achinko, D; Thailayil, J; Paton, D; Mireji, P O; Talesa, V; Masiga, D; Catteruccia, F

    2016-03-01

    Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) is the major Afro-tropical vector of malaria. Novel strategies proposed for the elimination and eradication of this mosquito vector are based on the use of genetic approaches, such as the sterile insect technique (SIT). These approaches rely on the ability of released males to mate with wild females, and depend on the application of effective protocols to assess the swarming and mating behaviours of laboratory-reared insects prior to their release. The present study evaluated whether large semi-field enclosures can be utilized to study the ability of males from a laboratory colony to respond to natural environmental stimuli and initiate normal mating behaviour. Laboratory-reared males exhibited spatiotemporally consistent swarming behaviour within the study enclosures. Swarm initiation, peak and termination time closely tracked sunset. Comparable insemination rates were observed in females captured in copula in the semi-field cages relative to females in small laboratory cages. Oviposition rates after blood feeding were also similar to those observed in laboratory settings. The data suggest that outdoor enclosures are suitable for studying swarming and mating in laboratory-bred males in field-like settings, providing an important reference for future studies aimed at assessing the comparative mating ability of strains for SIT and other vector control strategies. PMID:26508420

  15. Modeling of Anopheles minimus Mosquito NADPH-Cytochrome P450 Oxidoreductase (CYPOR and Mutagenesis Analysis

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    Pornpimol Rongnoparut

    2013-01-01

    Full Text Available Malaria is one of the most dangerous mosquito-borne diseases in many tropical countries, including Thailand. Studies in a deltamethrin resistant strain of Anopheles minimus mosquito, suggest cytochrome P450 enzymes contribute to the detoxification of pyrethroid insecticides. Purified A. minimus CYPOR enzyme (AnCYPOR, which is the redox partner of cytochrome P450s, loses flavin-adenosine di-nucleotide (FAD and FLAVIN mono-nucleotide (FMN cofactors that affect its enzyme activity. Replacement of leucine residues at positions 86 and 219 with phenylalanines in FMN binding domain increases FMN binding, enzyme stability, and cytochrome c reduction activity. Membrane-Bound L86F/L219F-AnCYPOR increases A. minimus P450-mediated pyrethroid metabolism in vitro. In this study, we constructed a comparative model structure of AnCYPOR using a rat CYPOR structure as a template. Overall model structure is similar to rat CYPOR, with some prominent differences. Based on primary sequence and structural analysis of rat and A. minimus CYPOR, C427R, W678A, and W678H mutations were generated together with L86F/L219F resulting in three soluble Δ55 triple mutants. The C427R triple AnCYPOR mutant retained a higher amount of FAD binding and increased cytochrome c reduction activity compared to wild-type and L86F/L219F-Δ55AnCYPOR double mutant. However W678A and W678H mutations did not increase FAD and NAD(PH bindings. The L86F/L219F double and C427R triple membrane-bound AnCYPOR mutants supported benzyloxyresorufin O-deakylation (BROD mediated by mosquito CYP6AA3 with a two- to three-fold increase in efficiency over wild-type AnCYPOR. The use of rat CYPOR in place of AnCYPOR most efficiently supported CYP6AA3-mediated BROD compared to all AnCYPORs.

  16. Some strains of Plasmodium falciparum, a human malaria parasite, evade the complement-like system of Anopheles gambiae mosquitoes.

    Science.gov (United States)

    Molina-Cruz, Alvaro; DeJong, Randall J; Ortega, Corrie; Haile, Ashley; Abban, Ekua; Rodrigues, Janneth; Jaramillo-Gutierrez, Giovanna; Barillas-Mury, Carolina

    2012-07-10

    Plasmodium falciparum lines differ in their ability to infect mosquitoes. The Anopheles gambiae L3-5 refractory (R) line melanizes most Plasmodium species, including the Brazilian P. falciparum 7G8 line, but it is highly susceptible to some African P. falciparum strains such as 3D7, NF54, and GB4. We investigated whether these lines differ in their ability to evade the mosquito immune system. Silencing key components of the mosquito complement-like system [thioester-containing protein 1 (TEP1), leucine-rich repeat protein 1, and Anopheles Plasmodium-responsive leucine-rich repeat protein 1] prevented melanization of 7G8 parasites, reverting the refractory phenotype. In contrast, it had no effect on the intensity of infection with NF54, suggesting that this line is able to evade TEP1-mediated lysis. When R females were coinfected with a line that is melanized (7G8) and a line that survives (3D7), the coinfection resulted in mixed infections with both live and encapsulated parasites on individual midguts. This finding shows that survival of individual parasites is parasite-specific and not systemic in nature, because parasites can evade TEP1-mediated lysis even when other parasites are melanized in the same midgut. When females from an extensive genetic cross between R and susceptible A. gambiae (G3) mosquitoes were infected with P. berghei, encapsulation was strongly correlated with the TEP1-R1 allele. However, P. falciparum 7G8 parasites were no longer encapsulated by females from this cross, indicating that the TEP1-R1 allele is not sufficient to melanize this line. Evasion of the A. gambiae immune system by P. falciparum may be the result of parasite adaptation to sympatric mosquito vectors and may be an important factor driving malaria transmission. PMID:22623529

  17. Sugar-fermenting yeast as an organic source of carbon dioxide to attract the malaria mosquito Anopheles gambiae

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    Spitzen Jeroen

    2010-10-01

    Full Text Available Abstract Background Carbon dioxide (CO2 plays an important role in the host-seeking process of opportunistic, zoophilic and anthropophilic mosquito species and is, therefore, commonly added to mosquito sampling tools. The African malaria vector Anopheles gambiae sensu stricto is attracted to human volatiles augmented by CO2. This study investigated whether CO2, usually supplied from gas cylinders acquired from commercial industry, could be replaced by CO2 derived from fermenting yeast (yeast-produced CO2. Methods Trapping experiments were conducted in the laboratory, semi-field and field, with An. gambiae s.s. as the target species. MM-X traps were baited with volatiles produced by mixtures of yeast, sugar and water, prepared in 1.5, 5 or 25 L bottles. Catches were compared with traps baited with industrial CO2. The additional effect of human odours was also examined. In the laboratory and semi-field facility dual-choice experiments were conducted. The effect of traps baited with yeast-produced CO2 on the number of mosquitoes entering an African house was studied in the MalariaSphere. Carbon dioxide baited traps, placed outside human dwellings, were also tested in an African village setting. The laboratory and semi-field data were analysed by a χ2-test, the field data by GLM. In addition, CO2 concentrations produced by yeast-sugar solutions were measured over time. Results Traps baited with yeast-produced CO2 caught significantly more mosquitoes than unbaited traps (up to 34 h post mixing the ingredients and also significantly more than traps baited with industrial CO2, both in the laboratory and semi-field. Adding yeast-produced CO2 to traps baited with human odour significantly increased trap catches. In the MalariaSphere, outdoor traps baited with yeast-produced or industrial CO2 + human odour reduced house entry of mosquitoes with a human host sleeping under a bed net indoors. Anopheles gambiae s.s. was not caught during the field trials

  18. Effect of Novaluron (Rimon 10 EC) on the mosquitoes Anopheles albimanus, Anopheles pseudopunctipennis, Aedes aegypti, Aedes albopictus and Culex quinquefasciatus from Chiapas, Mexico.

    Science.gov (United States)

    Arredondo-Jiménez, J I; Valdez-Delgado, K M

    2006-12-01

    Dengue fever is a serious problem in Mexico and vector control has not been effective enough at preventing outbreaks. Malaria is largely under control, but it is important that new control measures continue to be developed. Novaluron, a novel host-specific insect growth regulator and chitin synthesis inhibitor, has proved to be effective against agricultural pests, but its efficacy against larval mosquito vectors under field conditions remains unknown. In accordance with the World Health Organization Pesticide Evaluation Scheme, phase I, II and III studies were conducted to evaluate the efficacy and residual effect of Novaluron (Rimon 10 EC, Makhteshim, Beer-Sheva, Israel) on the malaria vectors Anopheles albimanus Wiedemann (Diptera: Culicidae) and Anopheles pseudopunctipennis Theobald, the dengue vectors Aedes aegypti (L) and Aedes albopictus Skuse and the nuisance mosquito Culex quinquefasciatus Say. Laboratory susceptibility tests yielded diagnostic concentrations for all five target species. Field trials to identify the optimum field dosage of Novaluron against Anopheles mosquitoes were carried out under semi-natural conditions in artificial plots and in vessels with wild mosquitoes. Efficacy was measured by monitoring mortality of larvae and pupae and the percentage of inhibition of emergence from floating cages. Dosages of Novaluron for field tests were based on pupal LC(99) (lethal concentration 99%) of An. pseudopunctipennis (0.166 mg/L) in plots and average pupal LC(99) of Ae. aegypti and Ae. albopictus (0.55 mg/L). At all dosages tested, Novaluron significantly reduced larval populations of An. albimanus, Culex coronator Dyar & Knab, Ae. albopictus and Cx. quinquefasciatus by approximately 90%, inhibited adult emergence of An. albimanus and An. pseudopunctipennis by approximately 97% for almost 4 months in experimental plots, and inhibited adult emergence of Ae. aegypti and Ae. albopictus by approximately 97% for up to 14 weeks. Recommended dosages of

  19. Reactive oxygen species detoxification by catalase is a major determinant of fecundity in the mosquito Anopheles gambiae

    OpenAIRE

    DeJong, Randall J.; Miller, Lisa M; Molina-Cruz, Alvaro; Gupta, Lalita; Kumar, Sanjeev; Barillas-Mury, Carolina

    2007-01-01

    The mosquito Anopheles gambiae is a primary vector of Plasmodium parasites in Africa. The effect of aging on reproductive output in A. gambiae females from three strains that differ in their ability to melanize Plasmodium and in their systemic levels of hydrogen peroxide (H2O2), a reactive oxygen species (ROS), was analyzed. The number of eggs oviposited after the first blood meal decreases with age in all strains; however, this decline was much more pronounced in the G3 (unselected) and R (r...

  20. Role of Culex and Anopheles mosquito species as potential vectors of rift valley fever virus in Sudan outbreak, 2007

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    Galal Fatma H

    2010-03-01

    Full Text Available Abstract Background Rift Valley fever (RVF is an acute febrile arthropod-borne viral disease of man and animals caused by a member of the Phlebovirus genus, one of the five genera in the family Bunyaviridae. RVF virus (RVFV is transmitted between animals and human by mosquitoes, particularly those belonging to the Culex, Anopheles and Aedes genera. Methods Experiments were designed during RVF outbreak, 2007 in Sudan to provide an answer about many raised questions about the estimated role of vector in RVFV epidemiology. During this study, adult and immature mosquito species were collected from Khartoum and White Nile states, identified and species abundance was calculated. All samples were frozen individually for further virus detection. Total RNA was extracted from individual insects and RVF virus was detected from Culex, Anopheles and Aedes species using RT-PCR. In addition, data were collected about human cases up to November 24th, 2007 to asses the situation of the disease in affected states. Furthermore, a historical background of the RVF outbreaks was discussed in relation to global climatic anomalies and incriminated vector species. Results A total of 978 mosquitoes, belonging to 3 genera and 7 species, were collected during Sudan outbreak, 2007. Anopheles gambiae arabiensis was the most frequent species (80.7% in White Nile state. Meanwhile, Cx. pipiens complex was the most abundant species (91.2% in Khartoum state. RT-PCR was used and successfully amplified 551 bp within the M segment of the tripartite negative-sense single stranded RNA genome of RVFV. The virus was detected in female, male and larval stages of Culex and Anopheles species. The most affected human age interval was 15-29 years old followed by ≥ 45 years old, 30-44 years old, and then 5-14 years old. Regarding to the profession, housewives followed by farmers, students, shepherd, workers and the free were more vulnerable to the infection. Furthermore, connection between

  1. Molecular evolution of immune genes in the malaria mosquito Anopheles gambiae.

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    Tovi Lehmann

    Full Text Available BACKGROUND: As pathogens that circumvent the host immune response are favoured by selection, so are host alleles that reduce parasite load. Such evolutionary processes leave their signature on the genes involved. Deciphering modes of selection operating on immune genes might reveal the nature of host-pathogen interactions and factors that govern susceptibility in host populations. Such understanding would have important public health implications. METHODOLOGY/FINDINGS: We analyzed polymorphisms in four mosquito immune genes (SP14D1, GNBP, defensin, and gambicin to decipher selection effects, presumably mediated by pathogens. Using samples of Anopheles arabiensis, An. quadriannulatus and four An. gambiae populations, as well as published sequences from other Culicidae, we contrasted patterns of polymorphisms between different functional units of the same gene within and between populations. Our results revealed selection signatures operating on different time scales. At the most recent time scale, within-population diversity revealed purifying selection. Between populations and between species variation revealed reduced differentiation (GNBP and gambicin at coding vs. noncoding- regions, consistent with balancing selection. McDonald-Kreitman tests between An. quadriannulatus and both sibling species revealed higher fixation rate of synonymous than nonsynonymous substitutions (GNBP in accordance with frequency dependent balancing selection. At the longest time scale (>100 my, PAML analysis using distant Culicid taxa revealed positive selection at one codon in gambicin. Patterns of genetic variation were independent of exposure to human pathogens. SIGNIFICANCE AND CONCLUSIONS: Purifying selection is the most common form of selection operating on immune genes as it was detected on a contemporary time scale on all genes. Selection for "hypervariability" was not detected, but negative balancing selection, detected at a recent evolutionary time scale

  2. Biochemical characterization of chitin synthase activity and inhibition in the African malaria mosquito, Anopheles gambiae

    Institute of Scientific and Technical Information of China (English)

    Xin Zhang; Kun Yan Zhu

    2013-01-01

    Chitin synthase (CHS) is an important enzyme catalyzing the formation of chitin polymers in all chitin containing organisms and a potential target site for insect pest control.However,our understanding of biochemical properties of insect CHSs has been very limited.We here report enzymatic and inhibitory properties of CHS prepared from the African malaria mosquito,Anopheles gambiae.Our study,which represents the first time to use a nonradioactive method to assay CHS activity in an insect species,determined the optimal conditions for measuring the enzyme activity,including pH,temperature,and concentrations of the substrate uridine diphosphate N-acetyl-D-glucosamine (UDPGlcNAc) and Mg++.The optimal pH was about 6.5-7.0,and the highest activity was detected at temperatures between 37℃ and 44℃.Dithithreitol is required to prevent melanization of the enzyme extract.CHS activity was enhanced at low concentration of GlcNAc,but inhibited at high concentrations.Proteolytic activation of the activity is significant both in the 500×g supernatant and the 40 000×g pellet.Our study revealed only slight in vitro inhibition ofA.gambiae CHS activity by diflubenzuron and nikkomycin Z at the highest concentration (2.5μmol/L) examined.There was no in vitro inhibition by polyoxin D at any concentration examined.Furthermore,we did not observe any in vivo inhibition of CHS activity by any of these chemicals at any concentration examined.Our results suggest that the inhibition of chitin synthesis by these chemicals is not due to direct inhibition of CHS in A.gambiae.

  3. Synergy in efficacy of fungal entomopathogens and permethrin against West African insecticide-resistant Anopheles gambiae mosquitoes.

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    Marit Farenhorst

    Full Text Available BACKGROUND: Increasing incidences of insecticide resistance in malaria vectors are threatening the sustainable use of contemporary chemical vector control measures. Fungal entomopathogens provide a possible additional tool for the control of insecticide-resistant malaria mosquitoes. This study investigated the compatibility of the pyrethroid insecticide permethrin and two mosquito-pathogenic fungi, Beauveria bassiana and Metarhizium anisopliae, against a laboratory colony and field population of West African insecticide-resistant Anopheles gambiae s.s. mosquitoes. METHODOLOGY/FINDINGS: A range of fungus-insecticide combinations was used to test effects of timing and sequence of exposure. Both the laboratory-reared and field-collected mosquitoes were highly resistant to permethrin but susceptible to B. bassiana and M. anisopliae infection, inducing 100% mortality within nine days. Combinations of insecticide and fungus showed synergistic effects on mosquito survival. Fungal infection increased permethrin-induced mortality rates in wild An. gambiae s.s. mosquitoes and reciprocally, exposure to permethrin increased subsequent fungal-induced mortality rates in both colonies. Simultaneous co-exposure induced the highest mortality; up to 70.3+/-2% for a combined Beauveria and permethrin exposure within a time range of one gonotrophic cycle (4 days. CONCLUSIONS/SIGNIFICANCE: Combining fungi and permethrin induced a higher impact on mosquito survival than the use of these control agents alone. The observed synergism in efficacy shows the potential for integrated fungus-insecticide control measures to dramatically reduce malaria transmission and enable control at more moderate levels of coverage even in areas where insecticide resistance has rendered pyrethroids essentially ineffective.

  4. Identification and expression profiling of putative odorant-binding proteins in the malaria mosquitoes, Anopheles gambiae and A.arabiensis

    Institute of Scientific and Technical Information of China (English)

    LI Zhengxi; Jing-Jiang ZHOU; SHEN Zuorui; Lin FIELD

    2004-01-01

    Olfaction plays a major role in host-seeking behaviour of mosquitoes. An informatics-based genome-wide analysis of odorant-binding protein (OBP) homologues is undertaken,and 32 putative OBP genes in total in the whole genome sequences of Anopheles gambiae are identified. Tissue-specific expression patterns of all A. gambiae OBP candidates are determined by semi-quantitative Reverse Transcription (RT)-PCR using mosquito actin gene as internal expression control standard. The results showed that 20 OBP candidates had strong expression in mosquito olfactory tissues (female antennae), which indicate that OBPs may play an important role in regulating mosquito olfactory behaviours. Species-specific expression patterns of all putative anopheline OBPs are also studied in two of the most important malaria vectors in A. gambiae complex, i.e.A. gambiae and A. arabiensis, which found 12 of the putative OBP genes examined displayed species-differential expression patterns. The cumulative relative expression intensity of the OBPs in A. arabiensis antennae was higher than that in A. gambiae (the ratio is 1441.45:1314.12), which might be due to their different host preference behaviour. While A.gambiae is a highly anthropophilic mosquito, A. arabiensis is more opportunistic (varying from anthropophilic to zoophilic). So the latter should need more OBPs to support its host selection preference. Identification of mosquito OBPs and verification of their tissue- and species-specific expression patterns represent the first step towards further molecular analysis of mosquito olfactory mechanism, such as recombinant expression and ligand identification.

  5. [Malaria mosquitoes (Diptera, Culicidae, Anopheles) of North Tajikistan, their ecology, and role in the transmission of malaria pathogens].

    Science.gov (United States)

    Kadamov, D S; Zvantseva, A B; Karimov, S S; Gordeev, M I; Goriacheva, I I; Ezhov, M N; Tadzhiboev, A

    2012-01-01

    Five species of malaria mosquitoes: An. artemievi, An. claviger, An. hyrcanus, An. superpictus, and An. pulcherrimus were found in North Tajikistan in 2006 - 2007. Species affiliation was identified according to the morphological signs of their larvae and imagoes, and by using the polymerase chain reaction-restriction fragment length polymorphism analysis. There was a larger number of An. hyrcanus (34%), An. artemievi (29%), and An. pulcherrimus (24%) and a smaller number of An. superpictus (11%); and An. claviger was few (2%). The hatching sites of the above species and the preferred types of their day refuges were found. The intensity of attack of different Anopheles species on humans and animals was studied. Among the North Tajikistan malaria mosquitoes, An. pulcherrimus and An. superpictus are of the greatest epidemiological importance as vehicles for transmission of malaria pathogens. An. artemievi and An. hyrcanus are minor vehicles. At present, An. claviger is of no epidemiological significance in transmitting malaria in North Tajikistan.

  6. Does polyandrous impede mosquito control by autocidal?

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    K.Jayaprakash

    2014-03-01

    Full Text Available Vector mosquito control by releasing genetically altered males has been attempted under the presumption that the females are monandrous. The present observation was through the sex–linked inheritance pattern of eye-colour and the estimation of polyandrous in in-vitro mating. A small proportion (18.2% of the female Anopheles stephensi population exhibited polyandrous on examination of 850 F1 adults when two types of males (white and black eyed where allowed to mate with homozygous white eyed females. The above results were discussed with relation to the consequences of the polyandrous trait in sterile insect technique, genetic control programmes.

  7. Larvicidal and repellent activities ofSida acuta Burm. F. (Family:Malvaceae) against three important vector mosquitoes

    Institute of Scientific and Technical Information of China (English)

    Marimuthu Govindarajan

    2010-01-01

    Objective:To determine the larvicidal and repellent activities ofSida acuta Burm. F. (Family: Malvaceae)extract against Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi. Methods: Twenty five late III instar larve of three mosquito species were exposed to various concentrations (15-90 mg/L) and were assayed in the laboratory by using the protocol ofWHO 2005; the24 h LC50 values of theSida acuta leaf extract was determined following Probit analysis. The repellent efficacy was determined against three mosquito species at three concentrations viz.,1.0, 2.5 and5.0mg/cm2 under the laboratory conditions.Results:Results showed varying degree of larvicidal activity of crude extract of Sida acuta against three important mosquitoes withLC50values ranging between38 to48 mg/L. The crude extract had strong repellent action against three species of mosquitoes as it provided100%protection againstAnopheles stephensi for 180min followed byAedes aegypti (150 min) andCulex quinquefasciatus (120 min).Conclusions:From the results it can be concluded the crude extract ofSida acuta was an excellent potential for controllingCulex quinquefasciatus, Aedes aegypti andAnopleles stephensi mosquitoes.

  8. Determination of nitric oxide metabolites, nitrate and nitrite, in Anopheles culicifacies mosquito midgut and haemolymph by anion exchange high-performance liquid chromatography: plausible mechanism of refractoriness

    OpenAIRE

    Adak Tridibesh; Raghavendra Kamaraju; Sharma Arun; Dash Aditya P

    2008-01-01

    Abstract Background The diverse physiological and pathological role of nitric oxide in innate immune defenses against many intra and extracellular pathogens, have led to the development of various methods for determining nitric oxide (NO) synthesis. NO metabolites, nitrite (NO2-) and nitrate (NO3-) are produced by the action of an inducible Anopheles culicifacies NO synthase (AcNOS) in mosquito mid-guts and may be central to anti-parasitic arsenal of these mosquitoes. Method While exploring a...

  9. Repellent, irritant and toxic effects of 20 plant extracts on adults of the malaria vector Anopheles gambiae mosquito.

    Directory of Open Access Journals (Sweden)

    Emilie Deletre

    Full Text Available Pyrethroid insecticides induce an excito-repellent effect that reduces contact between humans and mosquitoes. Insecticide use is expected to lower the risk of pathogen transmission, particularly when impregnated on long-lasting treated bednets. When applied at low doses, pyrethroids have a toxic effect, however the development of pyrethroid resistance in several mosquito species may jeopardize these beneficial effects. The need to find additional compounds, either to kill disease-carrying mosquitoes or to prevent mosquito contact with humans, therefore arises. In laboratory conditions, the effects (i.e., repellent, irritant and toxic of 20 plant extracts, mainly essential oils, were assessed on adults of Anopheles gambiae, a primary vector of malaria. Their effects were compared to those of DEET and permethrin, used as positive controls. Most plant extracts had irritant, repellent and/or toxic effects on An. gambiae adults. The most promising extracts, i.e. those combining the three types of effects, were from Cymbopogon winterianus, Cinnamomum zeylanicum and Thymus vulgaris. The irritant, repellent and toxic effects occurred apparently independently of each other, and the behavioural response of adult An. gambiae was significantly influenced by the concentration of the plant extracts. Mechanisms underlying repellency might, therefore, differ from those underlying irritancy and toxicity. The utility of the efficient plant extracts for vector control as an alternative to pyrethroids may thus be envisaged.

  10. Bitter-sensitive gustatory receptor neuron responds to chemically diverse insect repellents in the common malaria mosquito Anopheles quadrimaculatus

    Science.gov (United States)

    Sparks, Jackson T.; Dickens, Joseph C.

    2016-06-01

    Female mosquitoes feed on blood from animal hosts to obtain nutritional resources used for egg production. These contacts facilitate the spread of harmful human diseases. Chemical repellents are used to disrupt mosquito host-seeking and blood-feeding behaviors; however, little is known about the gustatory sensitivity of mosquitoes to known repellents. Here, we recorded electrical responses from gustatory receptor neurons (GRNs) housed within the labellar sensilla of female Anopheles quadrimaculatus to N,N-diethyl-3-methylbenzamide (DEET), picaridin, IR3535, 2-undecanone, p-menthane-3,8-diol, geraniol, trans-2-hexen-1-ol, quinine, and quinidine. A bitter-sensitive GRN responded to all tested repellents and quinine, a known feeding deterrent. Responses of the bitter-sensitive neuron to quinine and an isomer, quinidine, did not differ. Delayed bursts of electrical activity were observed in response to continuous stimulation with synthetic repellents at high concentrations. Electrophysiological recordings from bitter-sensitive GRNs associated with mosquito gustatory sensilla represent a convenient model to evaluate candidate repellents.

  11. Salivary Gland Proteome during Adult Development and after Blood Feeding of Female Anopheles dissidens Mosquitoes (Diptera: Culicidae)

    Science.gov (United States)

    Phattanawiboon, Benjarat; Jariyapan, Narissara; Mano, Chonlada; Roytrakul, Sittiruk; Paemanee, Atchara; Sor-Suwan, Sriwatapron; Sriwichai, Patchara; Saeung, Atiporn; Bates, Paul A.

    2016-01-01

    Understanding changes in mosquito salivary proteins during the time that sporozoite maturation occurs and after blood feeding may give information regarding the roles of salivary proteins during the malarial transmission. Anopheles dissidens (formerly Anopheles barbirostris species A1) is a potential vector of Plasmodium vivax in Thailand. In this study, analyses of the proteomic profiles of female An. dissidens salivary glands during adult development and after blood feeding were carried out using two-dimensional gel electrophoresis coupled with nano-liquid chromatography-mass spectrometry. Results showed at least 17 major salivary gland proteins present from day one to day 21 post emergence at 8 different time points sampled. Although there was variation observed, the patterns of protein expression could be placed into one of four groups. Fifteen protein spots showed significant depletion after blood feeding with the percentages of the amount of depletion ranging from 8.5% to 68.11%. The overall results identified various proteins, including a putative mucin-like protein, an anti-platelet protein, a long form D7 salivary protein, a putative gVAG protein precursor, a D7-related 3.2 protein, gSG7 salivary proteins, and a gSG6 protein. These results allow better understanding of the changes of the salivary proteins during the adult mosquito development. They also provide candidate proteins to investigate any possible link or not between sporozoite maturation, or survival of skin stage sporozoites, and salivary proteins. PMID:27669021

  12. The effect of aliphatic carboxylic acids on olfaction-based host-seeking of the malaria mosquito Anopheles gambiae sensu stricto

    NARCIS (Netherlands)

    Smallegange, R.C.; Qiu, Y.T.; Bukovinszkine-Kiss, G.; Loon, van J.J.A.; Takken, W.

    2009-01-01

    The role of aliphatic carboxylic acids in host-seeking response of the malaria mosquito Anopheles gambiae sensu stricto was examined both in a dual-choice olfactometer and with indoor traps. A basic attractive blend of ammonia + lactic acid served as internal standard odor. Single carboxylic acids w

  13. Combined effect of seaweed (Sargassum wightii) and Bacillus thuringiensis var. israelensis on the coastal mosquito,Anopheles sundaicus, in Tamil Nadu, India

    Science.gov (United States)

    Studies were made of the extract of Sargassum wightii combined with Bacillus thuringiensis var. israelensis (Bti) for control of the malaria vector Anopheles sundaicus. Treatment of mosquito larvae with 0.001% S. wightii extract indicated median lethal concentrations (LC50) of 88, 73, 134, 156, and...

  14. The influence of late-stage pupal irradiation and increased irradiated:un-irradiated male ratio on mating competitiveness of the malaria mosquito Anopheles arabiensis Patton

    NARCIS (Netherlands)

    Helinski, M.; Knols, B.G.J.

    2009-01-01

    Competitiveness of released males in genetic control programmes is of critical importance. In this paper, we explored two scenarios to compensate for the loss of mating competitiveness after pupal stage irradiation in males of the malaria mosquito Anopheles arabiensis. First, competition experiments

  15. Comparative susceptibility to permethrin of two Anopheles gambiae s.l. populations from Southern Benin, regarding mosquito sex, physiological status, and mosquito age

    Institute of Scientific and Technical Information of China (English)

    Nazaire Azoun; Rock Akpon; Roseric Azondekon; Alex Asidi; Martin Akogbto

    2014-01-01

    Objective: To investigate what kind of mosquito sample is necessary for the determination of insecticide susceptibility in malaria vectors. Methods:Larvae and pupae of Anopheles gambiae s.l. (An. gambiae) mosquitoes were collected from the breeding sites in Littoral and Oueme departments. The Centers for Disease Control and Prevention (CDC) susceptibility tests were conducted on unfed male and female mosquitoes aged 2-5 days old. CDC susceptibility tests were also conducted on unfed, blood fed and gravid female mosquitoes aged 2-5 days old. These susceptibility tests were also conducted on unfed and blood fed female mosquitoes aged 2-5 days old and 20 days old. CDC biochemical assay using synergist was also carried out to detect any increase in the activity of enzyme typically involved in insecticide metabolism. Results:Female An. gambiae Ladji and Sekandji populations were more susceptible than the males when they were unfed and aged 2-5 days old. The mortality rates of blood fed female An. gambiae Ladji and Sekandji populations aged 2-5 days old were lower than those obtained when females were unfed. In addition, the mortality rates of gravid female An. gambiae Ladji and Sekandji populations aged 2-5 days old were lower than those obtained when they were unfed. The mortality rate obtained when female An. gambiae Sekandji populations were unfed and aged 20 days old was higher than the one obtained when these populations were unfed and aged 2-5 days old. The results obtained after effects of synergist penicillin in beeswax on F1 progeny of An. gambiae Ladji populations resistant to permethrin showed that mono-oxygenases were involved in permethrin resistant F1 progeny from Ladji. Conclusions: The resistance is a hereditary and dynamic phenomenon which can be due to metabolic mechanisms like overproduction of detoxifying enzymes activity. Many factors influence vector susceptibility to insecticide. Among these factors, there are mosquito sex, mosquito age, its

  16. Ingested Human Insulin Inhibits the Mosquito NF-κB-Dependent Immune Response to Plasmodium falciparum

    Science.gov (United States)

    Corby-Harris, Vanessa; Green, Gabriel P.; Smithers, Hannah M.; Cheung, Kong W.; Riehle, Michael A.; Luckhart, Shirley

    2012-01-01

    We showed previously that ingested human insulin activates the insulin/IGF-1 signaling pathway in Anopheles stephensi and increases the susceptibility of these mosquitoes to Plasmodium falciparum. In other organisms, insulin can alter immune responsiveness through regulation of NF-κB transcription factors, critical elements for innate immunity that are also central to mosquito immunity. We show here that insulin signaling decreased expression of NF-κB-regulated immune genes in mosquito cells stimulated with either bacterial or malarial soluble products. Further, human insulin suppressed mosquito immunity through sustained phosphatidylinositol 3-kinase activation, since inhibition of this pathway led to decreased parasite development in the mosquito. Together, these data demonstrate that activation of the insulin/IGF-1 signaling pathway by ingested human insulin can alter NF-κB-dependent immunity, and ultimately the susceptibility, of mosquitoes to P. falciparum. PMID:22473605

  17. Molasses as a source of carbon dioxide for attracting the malaria mosquitoes Anopheles gambiae and Anopheles funestus

    OpenAIRE

    Mweresa, C. K.; Omusula, P.; Otieno, B.; Loon, van, R.R.; Takken, W.; Mukabana, W.R.

    2014-01-01

    Background. Most odour baits for haematophagous arthropods contain carbon dioxide (CO2). The CO2 is sourced artificially from the fermentation of refined sugar (sucrose), dry ice, pressurized gas cylinders or propane. These sources of CO2 are neither cost-effective nor sustainable for use in remote areas of sub-Saharan Africa. In this study, molasses was evaluated as a potential substrate for producing CO2 used as bait for malaria mosquitoes. Methods. The attraction of laboratory-reared and w...

  18. Salivary gland proteome analysis reveals modulation of anopheline unique proteins in insensitive acetylcholinesterase resistant Anopheles gambiae mosquitoes.

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    Sylvie Cornelie

    Full Text Available Insensitive acetylcholinesterase resistance due to a mutation in the acetylcholinesterase (ace encoding ace-1 gene confers cross-resistance to organophosphate and carbamate insecticides in Anopheles gambiae populations from Central and West Africa. This mutation is associated with a strong genetic cost revealed through alterations of some life history traits but little is known about the physiological and behavioural changes in insects bearing the ace-1(R allele. Comparative analysis of the salivary gland contents between An. gambiae susceptible and ace-1(R resistant strains was carried out to charaterize factors that could be involved in modifications of blood meal process, trophic behaviour or pathogen interaction in the insecticide-resistant mosquitoes. Differential analysis of the salivary gland protein profiles revealed differences in abundance for several proteins, two of them showing major differences between the two strains. These two proteins identified as saglin and TRIO are salivary gland-1 related proteins, a family unique to anopheline mosquitoes, one of them playing a crucial role in salivary gland invasion by Plasmodium falciparum sporozoites. Differential expression of two other proteins previously identified in the Anopheles sialome was also observed. The differentially regulated proteins are involved in pathogen invasion, blood feeding process, and protection against oxidation, relevant steps in the outcome of malaria infection. Further functional studies and insect behaviour experiments would confirm the impact of the modification of the sialome composition on blood feeding and pathogen transmission abilities of the resistant mosquitoes. The data supports the hypothesis of alterations linked to insecticide resistance in the biology of the primary vector of human malaria in Africa.

  19. Mosquitoes of Anopheles hyrcanus (Diptera, Culicidae) Group: Species Diagnostic and Phylogenetic Relationships.

    Science.gov (United States)

    Khrabrova, Natalia V; Andreeva, Yulia V; Sibataev, Anuarbek K; Alekseeva, Svetlana S; Esenbekova, Perizat A

    2015-09-01

    Herein, we report the results of study of Anopheles species in Primorsk and Khabarovsk regions of Russia. Three species of the Anopheles hyrcanus group: An. kleini, An. pullus, and An. lesteri were identified by molecular taxonomic diagnostics for the first time in Russia. Surprisingly, An. sinensis, which earlier was considered the only species of Anopheles in Russian Far East, was not observed. We analyzed nucleotide variation in the 610-bp fragment of the 5' end of the cytochrome c oxidase subunit I (COI) region. All species possessed a distinctive set of COI sequences. A maximum likelihood phylogenetic tree was constructed for members of the hyrcanus group. The examined Anopheles hyrcanus group members could be divided into two major subgroups: subgroup 1 (An. hyrcanus and An. pullus) and subgroup 2 (An. sinensis, An. kleini, and An. lesteri), which were found to be monophyletic.

  20. Predation on Mosquito Larvae by Mesocyclops thermocyclopoides (Copepoda: Cyclopoida) in the Presence of Alternate Prey

    Science.gov (United States)

    Kumar, Ram; Ramakrishna Rao, T.

    2003-11-01

    The cyclopoid copepod Mesocyclops thermocyclopoides, a dominant invertebrate predator in many shallow ponds and temporary water bodies in northern India, feeds on cladocerans, rotifers, ciliates and when present, on mosquito larvae also. We studied in the laboratory the prey consumption rates of the copepod on first and fourth instar larvae of two species of mosquito (Anopheles stephensi and Culex quinquefasciatus) in relation to their density. We also studied its prey selectivity with mosquito larvae in the presence of an alternate prey (the cladocerans-either Moina macrocopa or Ceriodaphnia cornuta) in different proportions. With either mosquito species, the copepod actively selected Instar-I larvae, avoiding the Instar-IV larvae, and with either instar, selected Anopheles stephensi over Culex quinquefasciatus. When prey choice included the cladoceran as an alternate prey, the copepod selected the cladoceran only when the other prey was Instar-IV mosquito larvae. Our results point to the potential and promise of M. thermocyclopoides as a biological agent for controlling larval populations of vectorially important mosquito species.

  1. Heterosis Increases Fertility, Fecundity, and Survival of Laboratory-Produced F1 Hybrid Males of the Malaria Mosquito Anopheles coluzzii

    Science.gov (United States)

    Ekechukwu, Nkiru E.; Baeshen, Rowida; Traorè, Sékou F.; Coulibaly, Mamadou; Diabate, Abdoulaye; Catteruccia, Flaminia; Tripet, Frédéric

    2015-01-01

    The success of vector control strategies aiming to decrease disease transmission via the release of sterile or genetically-modified male mosquitoes critically depends on mating between laboratory-reared males and wild females. Unfortunately, mosquito colonization, laboratory rearing, and genetic manipulations can all negatively affect male competitiveness. Heterosis is commonly used to produce domestic animals with enhanced vigor and homogenous genetic background and could therefore potentially improve the mating performance of mass-reared male mosquitoes. Here, we produced enhanced hybrid males of the malaria mosquito Anopheles coluzzii by crossing two strains colonized >35 and 8 years ago. We compared the amount of sperm and mating plug proteins they transferred to females, as well as their insemination rate, reproductive success and longevity under various experimental conditions. Across experiments, widespread adaptations to laboratory mating were detected in the older strain. In large-group mating experiments, no overall hybrid advantage in insemination rates and the amount of sperm and accessory gland proteins transferred to females was detected. Despite higher sperm activity, hybrid males did not appear more fecund. However, individual-male mating and laboratory-swarm experiments revealed that hybrid males, while inseminating fewer females than older inbred males, were significantly more fertile, producing larger mating plugs and drastically increasing female fecundity. Heterotic males also showed increased longevity. These results validate the use of heterosis for creating hybrid males with improved fitness from long-established inbred laboratory strains. Therefore, this simple approach could facilitate disease control strategies based on male mosquito releases with important ultimate benefits to human health. PMID:26497140

  2. An epithelial serine protease, AgESP, is required for Plasmodium invasion in the mosquito Anopheles gambiae.

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    Janneth Rodrigues

    Full Text Available BACKGROUND: Plasmodium parasites need to cross the midgut and salivary gland epithelia to complete their life cycle in the mosquito. However, our understanding of the molecular mechanism and the mosquito genes that participate in this process is still very limited. METHODOLOGY/PRINCIPAL FINDINGS: We identified an Anopheles gambiae epithelial serine protease (AgESP that is constitutively expressed in the submicrovillar region of mosquito midgut epithelial cells and in the basal side of the salivary glands that is critical for Plasmodium parasites to cross these two epithelial barriers. AgESP silencing greatly reduces Plasmodium berghei and Plasmodium falciparum midgut invasion and prevents the transcriptional activation of gelsolin, a key regulator of actin remodeling and a reported Plasmodium agonist. AgESP expression is highly induced in midgut cells invaded by Plasmodium, suggesting that this protease also participates in the apoptotic response to invasion. In salivary gland epithelial cells, AgESP is localized on the basal side--the surface with which sporozoites interact. AgESP expression in the salivary gland is also induced in response to P. berghei and P. falciparum sporozoite invasion, and AgESP silencing significantly reduces the number of sporozoites that invade this organ. CONCLUSION: Our findings indicate that AgESP is required for Plasmodium parasites to effectively traverse the midgut and salivary gland epithelial barriers. Plasmodium parasites need to modify the actin cytoskeleton of mosquito epithelial cells to successfully complete their life cycle in the mosquito and AgESP appears to be a major player in the regulation of this process.

  3. An Epithelial Serine Protease, AgESP, Is Required for Plasmodium Invasion in the Mosquito Anopheles gambiae

    Science.gov (United States)

    Rodrigues, Janneth; Oliveira, Giselle A.; Kotsyfakis, Michalis; Dixit, Rajnikant; Molina-Cruz, Alvaro; Jochim, Ryan; Barillas-Mury, Carolina

    2012-01-01

    Background Plasmodium parasites need to cross the midgut and salivary gland epithelia to complete their life cycle in the mosquito. However, our understanding of the molecular mechanism and the mosquito genes that participate in this process is still very limited. Methodology/Principal Findings We identified an Anopheles gambiae epithelial serine protease (AgESP) that is constitutively expressed in the submicrovillar region of mosquito midgut epithelial cells and in the basal side of the salivary glands that is critical for Plasmodium parasites to cross these two epithelial barriers. AgESP silencing greatly reduces Plasmodium berghei and Plasmodium falciparum midgut invasion and prevents the transcriptional activation of gelsolin, a key regulator of actin remodeling and a reported Plasmodium agonist. AgESP expression is highly induced in midgut cells invaded by Plasmodium, suggesting that this protease also participates in the apoptotic response to invasion. In salivary gland epithelial cells, AgESP is localized on the basal side–the surface with which sporozoites interact. AgESP expression in the salivary gland is also induced in response to P. berghei and P. falciparum sporozoite invasion, and AgESP silencing significantly reduces the number of sporozoites that invade this organ. Conclusion Our findings indicate that AgESP is required for Plasmodium parasites to effectively traverse the midgut and salivary gland epithelial barriers. Plasmodium parasites need to modify the actin cytoskeleton of mosquito epithelial cells to successfully complete their life cycle in the mosquito and AgESP appears to be a major player in the regulation of this process. PMID:22509400

  4. Expression Profiles and RNAi Silencing of Inhibitor of Apoptosis Transcripts in Aedes, Anopheles, and Culex Mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Puglise, Jason M; Estep, Alden S; Becnel, James J

    2016-03-01

    Effective mosquito control is vital to curtail the devastating health effects of many vectored diseases. RNA interference (RNAi)-mediated control of mosquitoes is an attractive alternative to conventional chemical pesticides. Previous studies have suggested that transcripts for inhibitors of apoptosis (IAPs) may be good RNAi targets. To revisit and extend previous reports, we examined the expression of Aedes aegypti (L.) IAPs (AaeIAPs) 1, 2, 5, 6, 9, and a viral IAP-associated factor (vIAF) as well as Anopheles quadrimaculatus Say and Culex quinquefasciatus Say IAP1 homologs (AquIAP1 and CquIAP1) in adult females. Expression profiles of IAPs suggested that some older female mosquitoes had significantly higher IAP mRNA levels when compared to the youngest ones. Minor differences in expression of AaeIAPs were observed in mosquitoes that imbibed a bloodmeal, but the majority of the time points (up to 48 h) were not significantly different. Although in vitro experiments with the Ae. aegypti Aag-2 cell line demonstrated that the various AaeIAPs could be effectively knocked down within one day after dsRNA treatment, only Aag-2 cells treated with dsIAP1 displayed apoptotic morphology. Gene silencing and mortality were also evaluated after topical application and microinjection of the same dsRNAs into female Ae. aegypti. In contrast to previous reports, topical administration of dsRNA against AaeIAP1 did not yield a significant reduction in gene expression or increased mortality. Knockdown of IAP1 and other IAPs by microinjection did not result in significant mortality. In toto, our findings suggest that IAPs may not be suitable RNAi targets for controlling adult mosquito populations.

  5. Curcuma Raktakanda is a Potential Larvicide for Mosquito Control.

    Science.gov (United States)

    Latha, C; Ammini, J

    2000-01-01

    The leaves and tuber of Curcuma raktakanda were investigated as a mosquito larvicide against the early fourth instar larvae of four mosquito species, viz., Culex quinquefasciatus , Culex sitiens , Aedes aegypti and Anopheles stephensi . The petroleum ether extract of the leaves and tuber exhibited toxicity towards all the test species. The LC 90 values of leaf extract for Cx. quinquefasciatus , Cx. sitiens , Ae. aegypti and An. stephensi were 46.77, 27.45, 58.75 and 45.81 mg/l,respectively. The LC 90 values of crude extract of tuber were 44.88, 29.11, 48.08 and 37.49 mg/l for Cx. quinquefasciatus , Cx. sitiens , Ae. aegypti and An. stephensi , respectively. The crude extract of the tuber was fractionated using column chromatography and the activity of the fractions was studied against the test species. The LC 90 values of the biologically active fraction for Cx. quinquefasciatus , Cx. sitiens , Ae. aegypti and An. stephensi were 18.50, 12.82, 19.95 and 18.19 mg/l, respectively. The extracts were active after storage for one year.

  6. Mosquito cell line glycoproteins: an unsuitable model system for the Plasmodium ookinete-mosquito midgut interaction?

    Directory of Open Access Journals (Sweden)

    Wilkins Simon

    2010-03-01

    Full Text Available Abstract Background Mosquito midgut glycoproteins may act as key recognition sites for the invading malarial ookinete. Effective transmission blocking strategies require the identification of novel target molecules. We have partially characterised the surface glycoproteins of two cell lines from two mosquito species; Anopheles stephensi and Anopheles gambiae, and investigated the binding of Plasmodium berghei ookinetes to carbohydrate ligands on the cells. Cell line extracts were run on SDS-PAGE gels and carbohydrate moieties determined by blotting against a range of biotinylated lectins. In addition, specific glycosidases were used to cleave the oligosaccharides. Results An. stephensi 43 and An. gambiae 55 cell line glycoproteins expressed oligosaccharides containing oligomannose and hybrid oligosaccharides, with and without α1-6 core fucosylation; N-linked oligosaccharides with terminal Galβ1-3GalNAc or GalNAcβ1-3Gal; O-linked α/βGalNAc. An. stephensi 43 cell line glycoproteins also expressed N-linked Galβ1-4R and O-linked Galβ1-3GalNAc. Although P. berghei ookinetes bound to both mosquito cell lines, binding could not be inhibited by GlcNAc, GalNAc or Galactose. Conclusions Anopheline cell lines displayed a limited range of oligosaccharides. Differences between the glycosylation patterns of the cell lines and mosquito midgut epithelial cells could be a factor why ookinetes did not bind in a carbohydrate inhibitable manner. Anopheline cell lines are not suitable as a potential model system for carbohydrate-mediated adhesion of Plasmodium ookinetes.

  7. Evaluation of Hexane Extract of Tuber of Root of Cyperus rotundus Linn (Cyperaceae for Repellency against Mosquito Vectors

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    S. P. Singh

    2009-01-01

    Full Text Available Hexane extract of tuber of plant Cyperus rotundus (Cyperaceae was screened under laboratory conditions for repellent activity against mosquito vector Anopheles culicifacies Giles species A (Diptera: Culicidae, Anopheles stephensi Liston (Diptera: Culicidae, and Culex quinquefasciatus Say (Diptera: Culicidae. The Cyperus rotundus tuber extract was used to determine their effect on mosquito vector, and comparison with the DEET (NN Diethyl 1-3 methyl Benzamide, formerly known as diethyl 1-m-toluamide. The tuber extracts showed more effective at all the dose. Result obtained from the laboratory experiment showed that the tuber extracts are more effective for repellency of allthe mosquito vector even at low dose. Clear dose response relationships were established with the highest dose of 10% tuber extract evoking 100% repellency. Percent protection obtained against An. culicifacies Giles species A 100% repellency in 4 hours, 6 hours, An. stephensi 100% repellency in 6 hours and Cx. quinquefasciatus was 100% repellency in 6 hours at the 10% concentration. Against DEET- 2.5% An. culicifacies A 100% repellency in 1 hour, 2 hours, 6 hours, An. stephensi have shown 100% repellency in 6 hours, and Culex quinquefasciatus have shown 100% repellency in 1 hour, 2 hours, 6 hours. The consolidated data of the repellency observed in different species is given and it is evident that the over all repellency rates varied between 80 and 100% for different repellents concentrations (2.5%, 5%, and 10%. The extract can be applied as an effective personal protective measure against mosquito bites.

  8. The interaction between a sexually transferred steroid hormone and a female protein regulates oogenesis in the malaria mosquito Anopheles gambiae.

    Directory of Open Access Journals (Sweden)

    Francesco Baldini

    2013-10-01

    Full Text Available Molecular interactions between male and female factors during mating profoundly affect the reproductive behavior and physiology of female insects. In natural populations of the malaria mosquito Anopheles gambiae, blood-fed females direct nutritional resources towards oogenesis only when inseminated. Here we show that the mating-dependent pathway of egg development in these mosquitoes is regulated by the interaction between the steroid hormone 20-hydroxy-ecdysone (20E transferred by males during copulation and a female Mating-Induced Stimulator of Oogenesis (MISO protein. RNAi silencing of MISO abolishes the increase in oogenesis caused by mating in blood-fed females, causes a delay in oocyte development, and impairs the function of male-transferred 20E. Co-immunoprecipitation experiments show that MISO and 20E interact in the female reproductive tract. Moreover MISO expression after mating is induced by 20E via the Ecdysone Receptor, demonstrating a close cooperation between the two factors. Male-transferred 20E therefore acts as a mating signal that females translate into an increased investment in egg development via a MISO-dependent pathway. The identification of this male-female reproductive interaction offers novel opportunities for the control of mosquito populations that transmit malaria.

  9. The Interaction between a Sexually Transferred Steroid Hormone and a Female Protein Regulates Oogenesis in the Malaria Mosquito Anopheles gambiae

    Science.gov (United States)

    Baldini, Francesco; Gabrieli, Paolo; South, Adam; Valim, Clarissa; Mancini, Francesca; Catteruccia, Flaminia

    2013-01-01

    Molecular interactions between male and female factors during mating profoundly affect the reproductive behavior and physiology of female insects. In natural populations of the malaria mosquito Anopheles gambiae, blood-fed females direct nutritional resources towards oogenesis only when inseminated. Here we show that the mating-dependent pathway of egg development in these mosquitoes is regulated by the interaction between the steroid hormone 20-hydroxy-ecdysone (20E) transferred by males during copulation and a female Mating-Induced Stimulator of Oogenesis (MISO) protein. RNAi silencing of MISO abolishes the increase in oogenesis caused by mating in blood-fed females, causes a delay in oocyte development, and impairs the function of male-transferred 20E. Co-immunoprecipitation experiments show that MISO and 20E interact in the female reproductive tract. Moreover MISO expression after mating is induced by 20E via the Ecdysone Receptor, demonstrating a close cooperation between the two factors. Male-transferred 20E therefore acts as a mating signal that females translate into an increased investment in egg development via a MISO-dependent pathway. The identification of this male–female reproductive interaction offers novel opportunities for the control of mosquito populations that transmit malaria. PMID:24204210

  10. Habitat characterization and mapping of Anopheles maculatus (Theobald) mosquito larvae in malaria endemic areas in Kuala Lipis, Pahang, Malaysia.

    Science.gov (United States)

    Rohani, A; Wan Najdah, W M A; Zamree, I; Azahari, A H; Mohd Noor, I; Rahimi, H; Lee, H L

    2010-07-01

    In Peninsular Malaysia, a large proportion of malaria cases occur in the central mountainous and forested parts of the country. As part of a study to assess remote sensing data as a tool for vector mapping, we conducted entomological surveys to determine the type of mosquitoes, their characteristics and the abundance of habitats of the vector Anopheles maculatus in malaria endemic areas in Pos Senderot. An. maculatus mosquitoes were collected from 49 breeding sites in Pos Senderot. An. maculatus preferred to breed in water pockets formed on the bank of rivers and waterfalls. The most common larval habitats were shallow pools 5.0-15.0 cm deep with clear water, mud substrate and plants or floatage. The mosquito also preferred open or partially shaded habitats. Breeding habitats were generally located at 100-400 m from the nearest human settlement. Changes in breeding characteristics were also observed. Instead of breeding in slow flowing streams, most larvae bred in small water pockets along the river margin. PMID:21073056

  11. Studies on mosquito larvicidal properties of Eucalyptus citriodora Hook (family-Myrtaceae).

    Science.gov (United States)

    Singh, R K; Dhiman, R C; Mittal, P K

    2007-12-01

    Hexane extract obtained from leaves of Eucalyptus citriodora Hook was tested against larvae of Anopheles stephensi Liston, Culex quinquefasciatus Say and Aedes aegypti Linn to assess its toxicity and growth inhibiting activity. The results showed better activity of hexane extract against larvae of An. stephensi Liston as compared to the larvae of Cx. quinquefasciatus Say and Ae. aegypti Linn. The LC50 values against IVth instar larvae of three species were 69.86, 81.12 & 91.76 ppm respectively after 24 hours and 26.7, 29.9 & 38.8 ppm respectively after 72 hours. At lowest concentration viz. 10 ppm, 73% larvae of An. stephensi Liston failed to emergence as adult mosquito while in Cx. quinquefasciatus Say and Ae. aegypti Linn only 10 & 6% larvae failed to emerge. Further observations showed some morphological abnormalities in same pupae which could not moult normally. These results clearly indicated growth inhibition effect of the hexane extract of Eucalyptus against mosquito larvae, particularly Anopheles species. Thus Eucalyptus citriodora Hook, which is commonly found in Northern India, has a great potential for the development of an eco-friendly herbal insecticidal product for control of mosquito breeding. PMID:18697593

  12. Mosquito nets treated with a mixture of chlorfenapyr and alphacypermethrin control pyrethroid resistant Anopheles gambiae and Culex quinquefasciatus mosquitoes in West Africa.

    Directory of Open Access Journals (Sweden)

    Raphael N'Guessan

    Full Text Available BACKGROUND: The effectiveness of insecticide treated nets is under threat across Africa south of the Sahara from the selection of pyrethroid resistance in Anopheles gambiae mosquitoes. To maintain progress against malaria it is necessary to identify alternative residual insecticides for mosquito nets. Mixtures of pyrethroid and insecticides with novel mode of action provide scope for both improved control and management of resistance through concurrent exposure to unrelated insecticides. METHODS: The pyrrole chlorfenapyr and the pyrethroid alphacypermethrin were tested individually and as a mixture on mosquito nets in an experimental hut trial in southern Benin against pyrethroid resistant An gambiae and Culex quinquefasciatus mosquitoes. The nets were deliberately holed to simulate the effect of wear and tear. RESULTS: The nets treated with the mixture of chlorfenapyr 200 mg/m² and alphacypermethrin 25 mg/m² killed a proportion of An gambiae (77%, 95%CI: 66-86% significantly greater than nets treated with alphacypermethrin 25 mg/m(2 (30%, 95%CI: 21-41% but not significantly different from nets treated with chlorfenapyr 200 mg/m² (69%, 95%CI: 57-78%. The nets treated with the mixtures procured personal protection against An gambiae biting(58-62% by a greater margin than the alphacypermethrin treated net (39%, whereas the chlorfenapyr treated net was not protective. A similar trend in mortality and blood feeding inhibition between treatments was observed in Cx quinquefasciatus to that seen in An. gambiae, although the effects were lower. A mixture of alphacypermethrin with chlorfenapyr applied at 100 mg/m² had an effect similar to the mixture with chlorfenapyr at 200 mg/m². CONCLUSION: The effectiveness of ITNs against pyrethroid resistant mosquitoes was restored by the mixture: the alphacypermethrin component reduced human-vector contact while the chlorfenapyr controlled pyrethroid-resistant mosquitoes. The complementary action of these

  13. Alstonia boonei De Wild oil extract in the management of mosquito (Anopheles gambiae, a vector of malaria disease

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    Kayode David Ileke

    2015-07-01

    Full Text Available Objective: To evaluate the insecticidal potential of Alstonia boonei (A. boonei oils and derivatives against different life stages of a malaria vector, Anopheles gambiae. Methods: The leaf, stem bark and root bark of A. boonei were collected from an open field and air dried before being blended to fine powder. Oils from this plant were extracted by cold extraction and were prepared at different concentrations. Contact toxicity of A. boonei was tested against the larvae and pupae of the insect while smoke toxicity of the plant materials in form of mosquito coil was tested against the adult insect. Results: Alstodine recorded the highest insect mortality rate and the order of susceptibility of the life stages of the insect to the plant was pupae alstonine > stem bark extract > leaf extract > root bark extract.

  14. Alstonia booneiDe Wildoil extract in the management of mosquito (Anopheles gambiae), a vector of malaria disease

    Institute of Scientific and Technical Information of China (English)

    Kayode David Ileke; Olaniyi Charles Ogungbite

    2015-01-01

    Objective:To evaluate the insecticidal potential ofAlstonia boonei(A. boonei)oils and derivatives against different life stages of a malaria vector,Anopheles gambiae. Methods:The leaf, stem bark and root bark ofA. boonei were collected from an open field and air dried before being blended to fine powder. Oils from this plant were extracted by cold extraction and were prepared at different concentrations. Contact toxicity ofA. boonei was tested against the larvae and pupae of the insect while smoke toxicity of the plant materials in form of mosquito coil was tested against the adult insect. Results: Alstodine recorded the highest insect mortality rate and the order of susceptibility of the life stages of the insect to the plant was pupae alstonine > stem bark extract > leaf extract > root bark extract.

  15. Hemocyte differentiation mediates the mosquito late-phase immune response against Plasmodium in Anopheles gambiae

    OpenAIRE

    Smith, Ryan C.; Barillas-Mury, Carolina; Jacobs-Lorena, Marcelo

    2015-01-01

    The innate immune response is a major determinant of malaria parasite success in its mosquito host. Previous experiments have implicated LPS-induced TNFα transcription factor (LITAF)-like 3 (LL3) as an integral component of the mosquito immune response to the malaria parasite. This study reports that LL3 influences oocyst survival and demonstrates its role in mosquito blood cell (hemocyte) differentiation in response to parasite infection. Integrating previous data, we provide evidence that h...

  16. Hydric stress-dependent effects of Plasmodium falciparum infection on the survival of wild-caught Anopheles gambiae female mosquitoes

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    Aboagye-Antwi Fred

    2010-08-01

    Full Text Available Abstract Background Whether Plasmodium falciparum, the agent of human malaria responsible for over a million deaths per year, causes fitness costs in its mosquito vectors is a burning question that has not yet been adequately resolved. Understanding the evolutionary forces responsible for the maintenance of susceptibility and refractory alleles in natural mosquito populations is critical for understanding malaria transmission dynamics. Methods In natural mosquito populations, Plasmodium fitness costs may only be expressed in combination with other environmental stress factors hence this hypothesis was tested experimentally. Wild-caught blood-fed Anopheles gambiae s.s. females of the M and S molecular form from an area endemic for malaria in Mali, West Africa, were brought to the laboratory and submitted to a 7-day period of mild hydric stress or kept with water ad-libitum. At the end of this experiment all females were submitted to intense desiccation until death. The survival of all females throughout both stress episodes, as well as their body size and infection status was recorded. The importance of stress, body size and molecular form on infection prevalence and female survival was investigated using Logistic Regression and Proportional-Hazard analysis. Results Females subjected to mild stress exhibited patterns of survival and prevalence of infection compatible with increased parasite-induced mortality compared to non-stressed females. Fitness costs seemed to be linked to ookinetes and early oocyst development but not the presence of sporozoites. In addition, when females were subjected to intense desiccation stress, those carrying oocysts exhibited drastically reduced survival but those carrying sporozoites were unaffected. No significant differences in prevalence of infection and infection-induced mortality were found between the M and S molecular forms of Anopheles gambiae. Conclusions Because these results suggest that infected

  17. Efficacy of AquatainTM, a monomolecular surface film, against the malaria vectors Anopheles stephensi and An. gambiae s.s. in the laboratory

    NARCIS (Netherlands)

    Bukhari, S.T.; Knols, B.G.J.

    2009-01-01

    Monomolecular films are used for mosquito control because of their asphyxiating effect on larvae and pupae. Compared with other films, Aquatain mosquito formulation (AMFTM) has an improved spreading ability and flexibility on a water surface. In the laboratory, AMFTM showed larvicidal, pupicidal, an

  18. A 15N stable isotope semen label to detect mating in the malaria mosquito Anopheles arabiensis Patton

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    Gludovacz Doris

    2008-07-01

    Full Text Available Abstract In previous studies it was determined that the stable isotope 13-carbon can be used as a semen label to detect mating events in the malaria mosquito Anopheles arabiensis. In this paper we describe the use of an additional stable isotope, 15-nitrogen (15N, for that same purpose. Both stable isotopes can be analysed simultaneously in a mass spectrometer, offering the possibility to detect both labels in one sample in order to study complex and difficult-to-detect mating events, such as multiple mating. 15N-glycine was added to larval rearing water and the target enrichment was 5 atom% 15N. Males from these trays were mated with unlabelled virgin females, and spiked spermathecae were analysed for isotopic composition after mating using mass spectrometry. Results showed that spermathecae positive for semen could be distinguished from uninseminated or control samples using the raw δ15N‰ values. The label persisted in spermathecae for up to 5 days after insemination, and males aged 10 days transferred similar amounts of label as males aged 4 days. There were no negative effects of the label on larval survival and male longevity. Enrichment of teneral mosquitoes after emergence was 4.85 ± 0.10 atom% 15N. A threshold value defined as 3 standard deviations above the mean of virgin (i.e. uninseminated spermathecae samples was successful in classifying a large proportion of samples correctly (i.e. on average 95%. We conclude that alongside 13C, 15N can be used to detect mating in Anopheles and the suitability of both labels is briefly discussed.

  19. Midgut epithelial responses of different mosquito-Plasmodium combinations: the actin cone zipper repair mechanism in Aedes aegypti.

    Science.gov (United States)

    Gupta, Lalita; Kumar, Sanjeev; Han, Yeon Soo; Pimenta, Paulo F P; Barillas-Mury, Carolina

    2005-03-15

    In vivo responses of midgut epithelial cells to ookinete invasion of three different vector-parasite combinations, Aedes aegypti-Plasmodium gallinaceum, Anopheles stephensi-Plasmodium berghei, and A. stephensi-P. gallinaceum, were directly compared by using enzymatic markers and immunofluorescence stainings. Our studies indicate that, in A. aegypti and A. stephensi ookinetes traverse the midgut via an intracellular route and inflict irreversible damage to the invaded cells. These two mosquito species differ, however, in their mechanisms of epithelial repair. A. stephensi detaches damaged cells by an actin-mediated budding-off mechanism when invaded by either P. berghei or P. gallinaceum. In A. aegypti, the midgut epithelium is repaired by a unique actin cone zipper mechanism that involves the formation of a cone-shaped actin aggregate at the base of the cell that closes sequentially, expelling the cellular contents into the midgut lumen as it brings together healthy neighboring cells. Invasion of A. stephensi by P. berghei induced expression of nitric oxide synthase and peroxidase activities, which mediate tyrosine nitration. These enzymes and nitrotyrosine, however, were not induced in the other two vector-parasite combinations examined. These studies indicate that the epithelial responses of different mosquito-parasite combinations are not universal. The implications of these observations to validate animal experimental systems that reflect the biology of natural vectors of human malarias are discussed. PMID:15753303

  20. Gustatory receptor neuron responds to chemically diverse insect repellents in the common malaria mosquito Anopheles quadrimaculatus

    Science.gov (United States)

    Female mosquitoes feed on blood from animal hosts to obtain nutritional resources used for egg production. These contacts facilitate the spread of harmful human diseases. Chemical repellents are used to disrupt mosquito host seeking and blood feeding behaviors; however, little is known about the g...

  1. The bionomics of the malaria mosquito Anopheles gambiae sensu lato in Southeast Tanzania.

    NARCIS (Netherlands)

    Lyimo, E.O.K.

    1993-01-01

    Size of adult mosquitoes is known to affect both population dynamics as well as disease transmission. Studies devoted to this topic have given different results for different species. For example in some mosquito species, large size was found to be associated with high fecundity and longer survival

  2. Larvicidal activity of methanolic leaf extracts of plant, Chromolaena odorata L. (Asteraceae against vector mosquitoes

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    Jagruti H. Sukhthankar

    2014-09-01

    Full Text Available Mosquitoes transmit malaria, filariasis, dengue, chikungunya, etc. Repeated use of insecticides for mosquito control has caused development of resistance, adverse effects on non-target organisms and serious environmental concerns. Hence alternative control measures are being explored inter alia plant based insecticides. We carried out larvicidal bioassays with methanolic extract of leaves of Chromolaena odorata (family Asteraceae against late instar larvae of disease vectors Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti. The highest mortality was observed in Cx. quinquefasciatus [LC50 = 43 ppm, (95% CI: 34 - 48 ppm; LC90 = 110 ppm (CI: 94 - 135 ppm] followed by Ae. aegypti [LC50 = 138 ppm, (CI: 121 - 157 ppm; LC90 = 463 ppm (CI: 386 - 584 ppm] and An. stephensi [LC50 = 1613 ppm (CI: 1364 - 1890 ppm; LC90 = 8306 ppm (CI: 6598 - 11076 ppm]. Being larvicidal, leaf extracts of Chromolaena odorata could be explored further.

  3. Green synthesis of silver nanoparticles for the control of mosquito vectors of malaria, filariasis, and dengue.

    Science.gov (United States)

    Arjunan, Naresh Kumar; Murugan, Kadarkarai; Rejeeth, Chandrababu; Madhiyazhagan, Pari; Barnard, Donald R

    2012-03-01

    A biological method was used to synthesize stable silver nanoparticles that were tested as mosquito larvicides against Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus. Annona squamosa leaf broth (5%) reduced aqueous 1 mM AgNO₃ to stable silver nanoparticles with an average size of 450 nm. The structure and percentage of synthesized nanoparticles was characterized by using ultraviolet spectrophotometry, X-Ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy methods. The median lethal concentrations (LC₅₀) of silver nanoparticles that killed fourth instars of Ae. aegypti, Cx. quinquefasciatus, and An. stephensi were 0.30, 0.41, and 2.12 ppm, respectively. Adult longevity (days) in male and female mosquitoes exposed as larvae to 0.1 ppm silver nanoparticles was reduced by ~30% (pnanoparticles decreased by 36% (p<0.05).

  4. Hemocyte differentiation mediates the mosquito late-phase immune response against Plasmodium in Anopheles gambiae.

    Science.gov (United States)

    Smith, Ryan C; Barillas-Mury, Carolina; Jacobs-Lorena, Marcelo

    2015-06-30

    Plasmodium parasites must complete development in the mosquito vector for transmission to occur. The mosquito innate immune response is remarkably efficient in limiting parasite numbers. Previous work has identified a LPS-induced TNFα transcription factor (LITAF)-like transcription factor, LITAF-like 3 (LL3), which significantly influences parasite numbers. Here, we demonstrate that LL3 does not influence invasion of the mosquito midgut epithelium or ookinete-to-oocyst differentiation but mediates a late-phase immune response that decreases oocyst survival. LL3 expression in the midgut and hemocytes is activated by ookinete midgut invasion and is independent of the mosquito microbiota, suggesting that LL3 may be a component of a wound-healing response. LL3 silencing abrogates the ability of mosquito hemocytes to differentiate and respond to parasite infection, implicating hemocytes as critical modulators of the late-phase immune response. PMID:26080400

  5. Hemocyte differentiation mediates the mosquito late-phase immune response against Plasmodium in Anopheles gambiae

    Science.gov (United States)

    Smith, Ryan C.; Barillas-Mury, Carolina; Jacobs-Lorena, Marcelo

    2015-01-01

    Plasmodium parasites must complete development in the mosquito vector for transmission to occur. The mosquito innate immune response is remarkably efficient in limiting parasite numbers. Previous work has identified a LPS-induced TNFα transcription factor (LITAF)-like transcription factor, LITAF-like 3 (LL3), which significantly influences parasite numbers. Here, we demonstrate that LL3 does not influence invasion of the mosquito midgut epithelium or ookinete-to-oocyst differentiation but mediates a late-phase immune response that decreases oocyst survival. LL3 expression in the midgut and hemocytes is activated by ookinete midgut invasion and is independent of the mosquito microbiota, suggesting that LL3 may be a component of a wound-healing response. LL3 silencing abrogates the ability of mosquito hemocytes to differentiate and respond to parasite infection, implicating hemocytes as critical modulators of the late-phase immune response. PMID:26080400

  6. Mosquito Fauna (Diptera: Culicidae of Hamedan County, Western Iran.

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    Amir Hossein Zahirnia

    2014-12-01

    Full Text Available This study aimed to identify and determine the larval and adult mosquitoes (Culicidae fauna in Hamedan County, western Iran.It was a cross-sectional study which took place in four area of the Hamedan County. Sampling methods for larvae, pupae and adults were dipping, hand catch, night catch and total catch. Larvae and adult mosquitoes collected and were sent to laboratory of Medical Entomology, Hamedan University of Medical Sciences, Hamedan, Iran for further identification to species level to determination of fauna. Data analysis was performed using SPSS software version19.Three genera and eight species of family Culicidae were collected and identified in Hamedan County, Hamedan Province, West Iran, during May to October 2013. These species included: Culex theileri, Cx. pipiens, Cx. antennatus, Culiseta subochrea, Cs. langiareolata, Anopheles superpictus, An. maculipennis and An. stephensi. The species Cx. antennatus and An. stephensi were reported for the first time in Hamedan County.An. stephensi and Cx. antennatus caught had not been previously recorded in Hamedan Province. Due to vast agricultural activities in the province which provides suitable environment for the establishment of various species of mosquitoes and since many of them are potential vectors of human and domesticated animal pathogens, their ecology needs to be studied extensively.

  7. Reactive oxygen species detoxification by catalase is a major determinant of fecundity in the mosquito Anopheles gambiae.

    Science.gov (United States)

    DeJong, Randall J; Miller, Lisa M; Molina-Cruz, Alvaro; Gupta, Lalita; Kumar, Sanjeev; Barillas-Mury, Carolina

    2007-02-13

    The mosquito Anopheles gambiae is a primary vector of Plasmodium parasites in Africa. The effect of aging on reproductive output in A. gambiae females from three strains that differ in their ability to melanize Plasmodium and in their systemic levels of hydrogen peroxide (H2O2), a reactive oxygen species (ROS), was analyzed. The number of eggs oviposited after the first blood meal decreases with age in all strains; however, this decline was much more pronounced in the G3 (unselected) and R (refractory to Plasmodium infection) strains than in the S (highly susceptible to Plasmodium) strain. Reduction of ROS levels in G3 and R females by administration of antioxidants reversed this age-related decline in fecundity. The S and G3 strains were fixed for two functionally different catalase alleles that differ at the second amino acid position (Ser2Trp). Biochemical analysis of recombinant proteins revealed that the Trp isoform has lower specific activity and higher Km than the Ser isoform, indicating that the former is a less efficient enzyme. The Trp-for-Ser substitution appears to destabilize the functional tetrameric form of the enzyme. Both alleles are present in the R strain, and Ser/Ser females had significantly higher fecundity than Trp/Trp females. Finally, a systemic reduction in catalase activity by dsRNA-mediated knockdown significantly reduced the reproductive output of mosquito females, indicating that catalase plays a central role in protecting the oocyte and early embryo from ROS damage. PMID:17284604

  8. Reactive oxygen species detoxification by catalase is a major determinant of fecundity in the mosquito Anopheles gambiae

    Science.gov (United States)

    DeJong, Randall J.; Miller, Lisa M.; Molina-Cruz, Alvaro; Gupta, Lalita; Kumar, Sanjeev; Barillas-Mury, Carolina

    2007-01-01

    The mosquito Anopheles gambiae is a primary vector of Plasmodium parasites in Africa. The effect of aging on reproductive output in A. gambiae females from three strains that differ in their ability to melanize Plasmodium and in their systemic levels of hydrogen peroxide (H2O2), a reactive oxygen species (ROS), was analyzed. The number of eggs oviposited after the first blood meal decreases with age in all strains; however, this decline was much more pronounced in the G3 (unselected) and R (refractory to Plasmodium infection) strains than in the S (highly susceptible to Plasmodium) strain. Reduction of ROS levels in G3 and R females by administration of antioxidants reversed this age-related decline in fecundity. The S and G3 strains were fixed for two functionally different catalase alleles that differ at the second amino acid position (Ser2Trp). Biochemical analysis of recombinant proteins revealed that the Trp isoform has lower specific activity and higher Km than the Ser isoform, indicating that the former is a less efficient enzyme. The Trp-for-Ser substitution appears to destabilize the functional tetrameric form of the enzyme. Both alleles are present in the R strain, and Ser/Ser females had significantly higher fecundity than Trp/Trp females. Finally, a systemic reduction in catalase activity by dsRNA-mediated knockdown significantly reduced the reproductive output of mosquito females, indicating that catalase plays a central role in protecting the oocyte and early embryo from ROS damage. PMID:17284604

  9. Molecular characterisation and chromosomal mapping of transcripts having tissue-specific expression in the malaria mosquito Anopheles gambiae: possible involvement in visual or olfactory processes.

    Science.gov (United States)

    Ricci, Irene; Santolamazza, Federica; Costantini, Carlo; Favia, Guido

    2002-01-01

    We have compared the transcriptional activity of heads, antennae + palps, and carcasses in the mosquito Anopheles gambiae by means of differential display PCR (DD-PCR). Three transcripts specifically or preferentially expressed in the heads and in the antennae + palps have been selected. All are very similar to genes related to visual and olfactory mechanisms of several different organisms. They have been named Ag arrestin, Ag rLDL, and Ag dynamin. The potential of the DD-PCR technique in identifying genes involved in mosquito behaviour and the usefulness of the molecular characterisation of these transcripts are discussed. PMID:11822731

  10. Towards a sterile insect technique field release of Anopheles arabiensis mosquitoes in Sudan: Irradiation, transportation, and field cage experimentation

    Directory of Open Access Journals (Sweden)

    Malcolm Colin A

    2008-04-01

    Full Text Available Abstract Background The work described in this article forms part of a study to suppress a population of the malaria vector Anopheles arabiensis in Northern State, Sudan, with the Sterile Insect Technique. No data have previously been collected on the irradiation and transportation of anopheline mosquitoes in Africa, and the first series of attempts to do this in Sudan are reported here. In addition, experiments in a large field cage under near-natural conditions are described. Methods Mosquitoes were irradiated in Khartoum and transported as adults by air to the field site earmarked for future releases (400 km from the laboratory. The field cage was prepared for experiments by creating resting sites with favourable conditions. The mating and survival of (irradiated laboratory males and field-collected males was studied in the field cage, and two small-scale competition experiments were performed. Results Minor problems were experienced with the irradiation of insects, mostly associated with the absence of a rearing facility in close proximity to the irradiation source. The small-scale transportation of adult mosquitoes to the release site resulted in minimal mortality ( Conclusion It is concluded that although conditions are challenging, there are no major obstacles associated with the small-scale irradiation and transportation of insects in the current setting. The field cage is suitable for experiments and studies to test the competitiveness of irradiated males can be pursued. The scaling up of procedures to accommodate much larger numbers of insects needed for a release is the next challenge and recommendations to further implementation of this genetic control strategy are presented.

  11. Mosquito immune responses and compatibility between Plasmodium parasites and anopheline mosquitoes

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    Molina-Cruz Alvaro

    2009-07-01

    Full Text Available Abstract Background Functional screens based on dsRNA-mediated gene silencing identified several Anopheles gambiae genes that limit Plasmodium berghei infection. However, some of the genes identified in these screens have no effect on the human malaria parasite Plasmodium falciparum; raising the question of whether different mosquito effector genes mediate anti-parasitic responses to different Plasmodium species. Results Four new An. gambiae (G3 genes were identified that, when silenced, have a different effect on P. berghei (Anka 2.34 and P. falciparum (3D7 infections. Orthologs of these genes, as well as LRIM1 and CTL4, were also silenced in An. stephensi (Nijmegen Sda500 females infected with P. yoelii (17XNL. For five of the six genes tested, silencing had the same effect on infection in the P. falciparum-An. gambiae and P. yoelii-An. stephensi parasite-vector combinations. Although silencing LRIM1 or CTL4 has no effect in An. stephensi females infected with P. yoelii, when An. gambiae is infected with the same parasite, silencing these genes has a dramatic effect. In An. gambiae (G3, TEP1, LRIM1 or LRIM2 silencing reverts lysis and melanization of P. yoelii, while CTL4 silencing enhances melanization. Conclusion There is a broad spectrum of compatibility, the extent to which the mosquito immune system limits infection, between different Plasmodium strains and particular mosquito strains that is mediated by TEP1/LRIM1 activation. The interactions between highly compatible animal models of malaria, such as P. yoelii (17XNL-An. stephensi (Nijmegen Sda500, is more similar to that of P. falciparum (3D7-An. gambiae (G3.

  12. Towards a sterile insect technique field release of Anopheles arabiensis mosquitoes in Sudan: Irradiation, transportation, and field cage experimentation

    OpenAIRE

    Malcolm Colin A; El-Motasim Waleed M; Hassan Mo'awia M; Helinski Michelle EH; Knols Bart GJ; El-Sayed Badria

    2008-01-01

    Abstract Background The work described in this article forms part of a study to suppress a population of the malaria vector Anopheles arabiensis in Northern State, Sudan, with the Sterile Insect Technique. No data have previously been collected on the irradiation and transportation of anopheline mosquitoes in Africa, and the first series of attempts to do this in Sudan are reported here. In addition, experiments in a large field cage under near-natural conditions are described. Methods Mosqui...

  13. Effects of bed net use, female size, and plant abundance on the first meal choice (blood vs sugar) of the malaria mosquito Anopheles gambiae

    OpenAIRE

    Stone Chris M; Jackson Bryan T; Foster Woodbridge A

    2012-01-01

    Abstract Background The purpose of this study was to determine whether the sugar-or-blood meal choice of Anopheles gambiae females one day after emergence is influenced by blood-host presence and accessibility, nectariferous plant abundance, and female size. This tested the hypothesis that the initial meal of female An. gambiae is sugar, even when a blood host is available throughout the night, and, if not, whether the use of a bed net diverts mosquitoes to sugar sources. Methods Females and ...

  14. Toxicity of essential oil from Indian borage on the larvae of the African malaria vector mosquito, Anopheles gambiae

    OpenAIRE

    Kweka Eliningaya J; Senthilkumar Annadurai; Venkatesalu Venugopalan

    2012-01-01

    Abstract Background Essential oils are currently studied for the control of different disease vectors, because of their efficacy on targeted organisms. In the present investigation, the larvicidal potential of essential oil extracted from Indian borage (Plectranthus amboinicus) was studied against the African anthropophagic malaria vector mosquito, Anopheles gambiae. The larvae of An. gambiae s.s laboratory colony and An. gambiae s.l of wild populations were assayed and the larval mortality w...

  15. Differential gene expression in abdomens of the malaria vector mosquito, Anopheles gambiae, after sugar feeding, blood feeding and Plasmodium berghei infection

    OpenAIRE

    Romans Patricia A; Kern Marcia K; Hillenmeyer Maureen E; Lobo Neil F; Dana Ali N; Collins Frank H

    2006-01-01

    Abstract Background Large scale sequencing of cDNA libraries can provide profiles of genes expressed in an organism under defined biological and environmental circumstances. We have analyzed sequences of 4541 Expressed Sequence Tags (ESTs) from 3 different cDNA libraries created from abdomens from Plasmodium infection-susceptible adult female Anopheles gambiae. These libraries were made from sugar fed (S), rat blood fed (RB), and P. berghei-infected (IRB) mosquitoes at 30 hours after the bloo...

  16. Efficacy of leaves extract of Calotropis procera Ait. (Asclepiadaceae) in controlling Anopheles arabiensis and Culex quinquefasciatus mosquitoes.

    Science.gov (United States)

    Elimam, Abdalla M; Elmalik, Khitma H; Ali, Faysal S

    2009-10-01

    The present study aimed to investigate, the larvicidal, adult emergence inhibition and oviposition deterrent activity of aqueous leaves extract of Calotropis procera against Anopheles arabiensis and Culex quinquefasciatus as natural mosquito larvicide. The larvicidal activity was monitored against 2nd, 3rd and 4th instar larvae of each mosquito species 24 h post-treatment. Adult emergence inhibition activity was tested by exposing 3rd instar larvae of each mosquito species to different concentrations of extracts (200, 400, 600, 800 and 1000 ppm for An. arabiensis and 100, 200, 300, 400, 500 and 600 ppm for Cx. quinquefasciatus). Probit analysis was used to analyze data from bioassay experiments. The oviposition deterrent activity was tested by using three different concentrations of extracts (1000, 500 and 200 for An. arabiensis, and 1000, 500 and 100 for Cx. quinquefasciatus) that caused high, moderate and low larval mortality in the larvicidal experiment against 3rd instar larvae. It was found that, LC50-LC90 values calculated were 273.53-783.43, 366.44-1018.59 and 454.99-1224.62 ppm for 2nd, 3rd and 4th larval instars, respectively, of An. arabiensis and 187.93-433.51, 218.27-538.27 and 264.85-769.13 ppm for 2nd, 3rd and 4th larval instars, respectively, of Cx. quinquefasciatus. Fifty percent of adult emergence inhibition (EI50) was shown at 277.90 and 183.65 ppm for An. arabiensis and Cx. quinquefasciatus, respectively. The pupal stage was not affected till a concentration of 5000 ppm. The extract showed oviposition deterrence and effective repellence against both mosquito species at different concentrations, with the observation on that maximal eggs were laid in low concentration of extract. These results suggest that the leaves extract of C. procera possess remarkable larvicidal, adult emergence inhibitor, repellent and oviposition deterrent effect against both An. arabiensis and Cx. quinquefasciatus, and might be used as natural biocides for mosquito

  17. Green Nanoparticles for Mosquito Control

    Science.gov (United States)

    Soni, Namita; Prakash, Soam

    2014-01-01

    Here, we have used the green method for synthesis of silver and gold nanoparticles. In the present study the silver (Ag) and gold (Au) nanoparticles (NPs) were synthesized by using the aqueous bark extract of Indian spice dalchini (Cinnamomum zeylanicum) (C. zyelanicum or C. verum J. Presl). Additionally, we have used these synthesized nanoparticles for mosquito control. The larvicidal activity has been tested against the malaria vector Anopheles stephensi and filariasis vector Culex quinquefasciatus. The results were obtained using UV-visible spectrophotometer and the images were recorded with a transmission electron microscope (TEM). The efficacy tests were then performed at different concentrations and varying numbers of hours by probit analysis. The synthesized AgNPs were in spherical shape and average sizes (11.77 nm AgNPs and 46.48 nm AuNPs). The larvae of An. stephensi were found highly susceptible to the synthesized AgNPs and AuNPs than the Cx. quinquefasciatus. These results suggest that the C. zeylanicum synthesized silver and gold nanoparticles have the potential to be used as an ideal ecofriendly approach for the control of mosquito. PMID:25243210

  18. Green Nanoparticles for Mosquito Control

    Directory of Open Access Journals (Sweden)

    Namita Soni

    2014-01-01

    Full Text Available Here, we have used the green method for synthesis of silver and gold nanoparticles. In the present study the silver (Ag and gold (Au nanoparticles (NPs were synthesized by using the aqueous bark extract of Indian spice dalchini (Cinnamomum zeylanicum (C. zyelanicum or C. verum J. Presl. Additionally, we have used these synthesized nanoparticles for mosquito control. The larvicidal activity has been tested against the malaria vector Anopheles stephensi and filariasis vector Culex quinquefasciatus. The results were obtained using UV-visible spectrophotometer and the images were recorded with a transmission electron microscope (TEM. The efficacy tests were then performed at different concentrations and varying numbers of hours by probit analysis. The synthesized AgNPs were in spherical shape and average sizes (11.77 nm AgNPs and 46.48 nm AuNPs. The larvae of An. stephensi were found highly susceptible to the synthesized AgNPs and AuNPs than the Cx. quinquefasciatus. These results suggest that the C. zeylanicum synthesized silver and gold nanoparticles have the potential to be used as an ideal ecofriendly approach for the control of mosquito.

  19. Using Stable Isotopes of Carbon and Nitrogen to Mark Wild Populations of Anopheles and Aedes Mosquitoes in South-Eastern Tanzania

    Science.gov (United States)

    Opiyo, Mercy A.; Hamer, Gabriel L.; Lwetoijera, Dickson W.; Auckland, Lisa D.; Majambere, Silas; Okumu, Fredros O.

    2016-01-01

    Background Marking wild mosquitoes is important for understanding their ecology, behaviours and role in disease transmission. Traditional insect marking techniques include using fluorescent dyes, protein labels, radioactive labels and tags, but such techniques have various limitations; notably low marker retention and inability to mark wild mosquitoes at source. Stable isotopes are gaining wide spread use for non-invasive marking of arthropods, permitting greater understanding of mosquito dispersal and responses to interventions. We describe here a simple technique for marking naturally-breeding malaria and dengue vectors using stable isotopes of nitrogen (15N) and carbon (13C), and describe potential field applications. Methods We created man-made aquatic mosquito habitats and added either 15N-labelled potassium nitrate or 13C-labelled glucose, leaving non-adulterated habitats as controls. We then allowed wild mosquitoes to lay eggs in these habitats and monitored their development in situ. Pupae were collected promptly as they appeared and kept in netting cages. Emergent adults (in pools of ~4 mosquitoes/pool) and individually stored pupae were desiccated and analysed using Isotope Ratio Mass Spectrometry (IRMS). Findings Anopheles gambiae s.l and Aedes spp. from enriched 13C and enriched 15N larval habitats had significantly higher isotopic levels than controls (P = 0.005), and both isotopes produced sufficient distinction between marked and unmarked mosquitoes. Mean δ15N for enriched females and males were 275.6±65.1 and 248.0±54.6, while mean δ15N in controls were 2.1±0.1 and 3.9±1.7 respectively. Similarly, mean δ13C for enriched females and males were 36.08±5.28 and 38.5±6.86, compared to -4.3±0.2 and -7.9±3.6 in controls respectively. Mean δ15N and δ13C was significantly higher in any pool containing at least one enriched mosquito compared to pools with all unenriched mosquitoes, P<0.001. In all cases, there were variations in standardized

  20. The bionomics of the malaria mosquito Anopheles gambiae sensu lato in Southeast Tanzania.

    OpenAIRE

    Lyimo, E.O.K.

    1993-01-01

    Size of adult mosquitoes is known to affect both population dynamics as well as disease transmission. Studies devoted to this topic have given different results for different species. For example in some mosquito species, large size was found to be associated with high fecundity and longer survival (Steinwascher, 1982; Nasci, 1986a; 1986b; 1987) but in others large size did not result in longer survival (Walker et al ., 1987; Landry et al ., 1988; Pumpuni & Walker, 1989). Similar data were fo...

  1. Malaria mosquitoes host-locate and feed upon caterpillars.

    Directory of Open Access Journals (Sweden)

    Justin George

    Full Text Available Adult female mosquitoes need blood to develop their eggs and both sexes use nectar and honeydew as carbohydrate resources for flight, survival and to enhance reproduction. However, there are also a few reports in the literature of mosquitoes feeding on haemolymph of soft-bodied insects such as caterpillars. The frequency and significance of this entomophagous behavior is not well understood, but is thought to be a vestige of ancestral feeding behavior or an opportunistic behavior that has evolved over time. In our current paper we investigated the extent to which the malaria mosquito, Anopheles stephensi, is attracted to, and can successfully feed on, larvae of two common moth species, Manduca sexta and Heliothis subflexa. Using y-tube olfactometer assays we found that female An. stephensi readily flew upwind to and landed on the caterpillars of both moth species. The nature of the volatile cues used in host location remains unclear but respirometer studies suggest a possible role of CO2. Laboratory cage assays further showed that the female mosquitoes were able to actively feed on moth larvae and gain sufficient nutritional benefit to influence survival. The extent to which such an opportunistic behavior occurs in the field has yet to be explored but our results suggest that this haemolymph feeding behavior could play a role in malaria mosquito life history and could provide a novel mechanism for horizontal transmission of pathogens and other micro-organisms between hosts.

  2. Repellent properties of Cardiospermum halicacabum Linn. (Family:Sapindaceae) plant leaf extracts against three important vector mosquitoes

    Institute of Scientific and Technical Information of China (English)

    M Govindarajan; R Sivakumar

    2012-01-01

    Objective: To determine repellent activity of hexane, ethyl acetate, benzene, chloroform and methanol extract of Cardiospermum halicacabum (C. halicacabum) against Culex quinquefasciatus (Cx. quinquefasciatus), Aedes aegypti (Ae. aegypti) and Anopheles stephensi (An. stephensi).Methods:Evaluation was carried out in a net cage (45 cm×30 cm×25 cm) containing 100 blood starved female mosquitoes of three mosquito species and were assayed in the laboratory condition by using the protocol of WHO 2005; The plant leaf crude extracts of C. halicacabum was applied at 1.0, 2.5, and 5.0 mg/cm2 separately in the exposed area of the fore arm. Only ethanol served as control. Results: In this observation, the plant crude extracts gave protection against mosquito bites without any allergic reaction to the test person, and also, the repellent activity was dependent on the strength of the plant extracts. The tested plant crude extracts had exerted promising repellent against all the three mosquitoes. Conclusions: From the results it can be concluded the crude extract of C. halicacabum was potential for controlling Cx. quinquefasciatus,Ae. aegypti and An. stephensi mosquitoes.

  3. Genetic diversity in two sibling species of the Anopheles punctulatus group of mosquitoes on Guadalcanal in the Solomon Islands

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    Harada Masakazu

    2008-11-01

    Full Text Available Abstract Background The mosquito Anopheles irenicus, a member of the Anopheles punctulatus group, is geographically restricted to Guadalcanal in the Solomon Islands. It shows remarkable morphological similarities to one of its sibling species, An. farauti sensu stricto (An. farauti s.s., but is dissimilar in host and habitat preferences. To infer the genetic variations between these two species, we have analyzed mitochondrial cytochrome oxidase subunit II (COII and nuclear ribosomal internal transcribed spacer 2 (ITS2 sequences from Guadalcanal and from one of its nearest neighbours, Malaita, in the Solomon Islands. Results An. farauti s.s. was collected mostly from brackish water and by the human bait method on both islands, whereas An. irenicus was only collected from fresh water bodies on Guadalcanal Island. An. irenicus is distributed evenly with An. farauti s.s. (ΦSC = 0.033, 0.38% and its range overlaps in three of the seven sampling sites. However, there is a significant population genetic structure between the species (ΦCT = 0.863, P ST = 0.865, P FST = 0.878, P An. irenicus is a monophyletic species, not a hybrid, and is closely related to the An. farauti s.s. on Guadalcanal. The time estimator suggests that An. irenicus diverged from the ancestral An. farauti s.s. on Guadalcanal within 29,000 years before present (BP. An. farauti s.s. expanded much earlier on Malaita (texp = 24,600 BP than the populations on Guadalcanal (texp = 16,800 BP for An. farauti s.s. and 14,000 BP for An. irenicus. Conclusion These findings suggest that An. irenicus and An. farauti s.s. are monophyletic sister species living in sympatry, and their populations on Guadalcanal have recently expanded. Consequently, the findings further suggest that An. irenicus diverged from the ancestral An. farauti s.s. on Guadalcanal.

  4. Inhibition of Malaria Infection in Transgenic Anopheline Mosquitoes Lacking Salivary Gland Cells.

    Science.gov (United States)

    Yamamoto, Daisuke S; Sumitani, Megumi; Kasashima, Katsumi; Sezutsu, Hideki; Matsuoka, Hiroyuki

    2016-09-01

    Malaria is an important global public health challenge, and is transmitted by anopheline mosquitoes during blood feeding. Mosquito vector control is one of the most effective methods to control malaria, and population replacement with genetically engineered mosquitoes to block its transmission is expected to become a new vector control strategy. The salivary glands are an effective target tissue for the expression of molecules that kill or inactivate malaria parasites. Moreover, salivary gland cells express a large number of molecules that facilitate blood feeding and parasite transmission to hosts. In the present study, we adapted a functional deficiency system in specific tissues by inducing cell death using the mouse Bcl-2-associated X protein (Bax) to the Asian malaria vector mosquito, Anopheles stephensi. We applied this technique to salivary gland cells, and produced a transgenic strain containing extremely low amounts of saliva. Although probing times for feeding on mice were longer in transgenic mosquitoes than in wild-type mosquitoes, transgenic mosquitoes still successfully ingested blood. Transgenic mosquitoes also exhibited a significant reduction in oocyst formation in the midgut in a rodent malaria model. These results indicate that mosquito saliva plays an important role in malaria infection in the midgut of anopheline mosquitoes. The dysfunction in the salivary glands enabled the inhibition of malaria transmission from hosts to mosquito midguts. Therefore, salivary components have potential in the development of new drugs or genetically engineered mosquitoes for malaria control. PMID:27598328

  5. Laboratory evaluation of methanolic extract of Atlantia monophylla (Family: Rutaceae against immature stages of mosquitoes and non-target organisms

    Directory of Open Access Journals (Sweden)

    N Sivagnaname

    2004-02-01

    Full Text Available Methanolic extracts of the leaves of Atlantia monophylla (Rutaceae were evaluated for mosquitocidal activity against immature stages of three mosquito species, Culex quinquefasciatus, Anopheles stephensi, and Aedes aegypti in the laboratory.Larvae of Cx. quinquefasciatus and pupae of An. stephensi were found more susceptible, with LC50 values of 0.14 mg/l and 0.05 mg/l, respectively. Insect growth regulating activity of this extract was more pronounced against Ae. aegypti, with EI50 value 0.002 mg/l. The extract was found safe to aquatic mosquito predators Gambusia affinis, Poecilia reticulata, and Diplonychus indicus, with the respective LC50 values of 23.4, 21.3, and 5.7 mg/l. The results indicate that the mosquitocidal effects of the extract of this plant were comparable to neem extract and certain synthetic chemical larvicides like fenthion, methoprene, etc.

  6. Apolipophorin-III Mediates Antiplasmodial Epithelial Responses in Anopheles gambiae (G3) Mosquitoes

    OpenAIRE

    Gupta, Lalita; Noh, Ju Young; Jo, Yong Hun; Oh, Seung Han; Kumar, Sanjeev; Noh, Mi Young; Lee, Yong Seok; Cha, Sung-Jae; Seo, Sook Jae; Kim, Iksoo; Han, Yeon Soo; Barillas-Mury, Carolina

    2010-01-01

    Background Apolipophorin-III (ApoLp-III) is known to play an important role in lipid transport and innate immunity in lepidopteran insects. However, there is no evidence of involvement of ApoLp-IIIs in the immune responses of dipteran insects such as Drosophila and mosquitoes. Methodology/Principal Findings We report the molecular and functional characterization of An. gambiae apolipophorin-III (AgApoLp-III). Mosquito ApoLp-IIIs have diverged extensively from those of lepidopteran insects; ho...

  7. Expression of trypsin modulating oostatic factor (TMOF in an entomopathogenic fungus increases its virulence towards Anopheles gambiae and reduces fecundity in the target mosquito

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    Kamareddine Layla

    2013-01-01

    Full Text Available Abstract Background Adult and larval mosquitoes regulate food digestion in their gut with trypsin modulating oostatic factor (TMOF, a decapeptide hormone synthesized by the ovaries and the neuroendocrine system. TMOF is currently being developed as a mosquitocide, however, delivery of the peptide to the mosquito remains a significant challenge. Entomopathogenic fungi offer a means for targeting mosquitoes with TMOF. Findings The efficacy of wild type and transgenic Beauveria bassiana strains expressing Aedes aegypti TMOF (Bb-Aa1 were evaluated against larvae and sugar- and blood-fed adult Anopheles gambiae mosquitoes using insect bioassays. Bb-Aa1 displayed increased virulence against larvae, and sugar and blood fed adult A. gambiae when compared to the wild type parent strain. Median lethal dose (LD50 values decreased by ~20% for larvae, and ~40% for both sugar and blood-fed mosquitoes using Bb-Aa1 relative to the wild type parent. Median lethal time (LT50 values were lower for blood-fed compared to sugar-fed mosquitoes in infections with both wild type and Bb-Aa1. However, infection using Bb-Aa1 resulted in 15% to 25% reduction in LT50 values for sugar- and blood fed mosquitoes, and ~27% for larvae, respectively, relative to the wild type parent. In addition, infection with Bb-Aa1 resulted in a dramatic reduction in fecundity of the target mosquitoes. Conclusions B. bassiana expressing Ae. aegypti TMOF exhibited increased virulence against A. gambiae compared to the wild type strain. These data expand the range and utility of entomopathogenic fungi expressing mosquito-specific molecules to improve their biological control activities against mosquito vectors of disease.

  8. Breeding of Anopheles mosquitoes in irrigated areas of South Punjab, Pakistan

    DEFF Research Database (Denmark)

    Herrel, N; Amerasinghe, F P; Ensink, J;

    2001-01-01

    As part of investigations on potential linkages between irrigation and malaria transmission, all surface water bodies in and around three villages along an irrigation distributary in South Punjab, Pakistan, were surveyed for anopheline mosquito larvae (Diptera: Culicidae) from April 1999 to March...

  9. Reduction of malaria transmission to Anopheles mosquitoes with a six-dose regimen of co-artemether.

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    Colin J Sutherland

    2005-04-01

    Full Text Available BACKGROUND: Resistance of malaria parasites to chloroquine (CQ and sulphadoxine-pyrimethamine (SP is increasing in prevalence in Africa. Combination therapy can both improve treatment and provide important public health benefits if it curbs the spread of parasites harbouring resistance genes. Thus, drug combinations must be identified which minimise gametocyte emergence in treated cases, and so prevent selective transmission of parasites resistant to any of the partner drugs. METHODS AND FINDINGS: In a randomised controlled trial, 497 children with uncomplicated falciparum malaria were treated with CQ and SP (three doses and one dose respectively; n = 91, or six doses of artemether in fixed combination with lumefantrine (co-artemether [Coartem, Riamet] (n = 406. Carriage rates of Plasmodium falciparum gametocytes and trophozoites were measured 7, 14, and 28 d after treatment. The infectiousness of venous blood from 29 children carrying P. falciparum gametocytes 7 d after treatment was tested by membrane-feeding of Anopheles mosquitoes. Children treated with co-artemether were significantly less likely to carry gametocytes within the 4 weeks following treatment than those receiving CQ/SP (30 of 378 [7.94%] versus 42 of 86 [48.8%]; p < 0.0001. Carriers in the co-artemether group harboured gametocytes at significantly lower densities, for shorter periods (0.3 d versus 4.2 d; p < 0.0001 and were less infectious to mosquitoes at day 7 (p < 0.001 than carriers who had received CQ/SP. CONCLUSIONS: Co-artemether is highly effective at preventing post-treatment transmission of P. falciparum. Our results suggest that co-artemether has specific activity against immature sequestered gametocytes, and has the capacity to minimise transmission of drug-resistant parasites.

  10. Chemical composition and larvicidal activity of Blumea densiflora essential oils against Anopheles anthropophagus: a malarial vector mosquito.

    Science.gov (United States)

    Zhu, Liang; Tian, Yingjuan

    2011-11-01

    Blumea densiflora, an edible and medicinal plant, is chiefly distributed in Southeast Asia and South Asia. Essential oils extracted by steam distillation from B. densiflora were investigated for their chemical composition and larvicidal activity against Anopheles anthropophagus, the primary vector of malaria in China and other East Asian countries. Totally, 46 compounds were identified by gas chromatography and mass spectroscopy. The major chemical compounds identified were borneol (11.43%), germacrene D (8.66%), β-caryophyllene (6.68%), γ-terpinene (4.35%), sabinene (4.34%), and β-bisabolene (4.24%). A series of concentrations of essential oil (that ranged from 6.25 to 150 ppm) were tested against A. anthropophagus fourth-instar larvae according to WHO recommendation. In general, larval mortality increased as concentration and exposure time increased, indicating a dose-dependent effect, and high insecticidal activity showed that 100% mortality occurred within 6 h at 150 ppm, 10 h at 100 ppm, 30 h at 50 ppm, and 30 h at 25 ppm essential oil concentration. The LC(50) values were 22.32 (after 12 h) and 10.55 ppm (after 24 h), and the LC(90) values were 54.04 (after 12 h) and 33.56 ppm (after 24 h). Pylarvex, the reference standard, had better larvicidal activity, causing 100% mortality within 2 h at 150 ppm and within 6 h at 6.25 ppm. The results clearly reveal that the essential oil of B. densiflora served as a potential, eco-friendly mosquito larvicide against the malarial vector mosquito A. anthropophagus.

  11. Toxicity of essential oil from Indian borage on the larvae of the African malaria vector mosquito, Anopheles gambiae

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    Kweka Eliningaya J

    2012-12-01

    Full Text Available Abstract Background Essential oils are currently studied for the control of different disease vectors, because of their efficacy on targeted organisms. In the present investigation, the larvicidal potential of essential oil extracted from Indian borage (Plectranthus amboinicus was studied against the African anthropophagic malaria vector mosquito, Anopheles gambiae. The larvae of An. gambiae s.s laboratory colony and An. gambiae s.l of wild populations were assayed and the larval mortality was observed at 12, 24 and 48 h after exposure period with the concentrations of 3.125, 6.25, 12.5, 25, 50 and 100 ppm. Findings Larval mortality rates of the essential oil was entirely time and dose dependent. The LC50 values of the laboratory colony were 98.56 (after 12h 55.20 (after 24 h and 32.41 ppm (after 48 h and the LC90 values were 147.40 (after 12h, 99.09 (after 24 h and 98.84 ppm (after 48 h. The LC50 and LC90 values of the wild population were 119.52, 179.85 (after 12h 67.53, 107.60 (after 24 h and 25.51, 111.17 ppm (after 48 h respectively. The oil showed good larvicidal potential after 48 h of exposure period against An. gambiae. The essential oil of Indian borage is a renowned natural source of larvicides for the control of the African malaria vector mosquito, An. gambiae. Conclusion The larvicidal efficacy shown by plant extracts against An. gambiae should be tested in semi field and small scale trials for effective compounds to supplement the existing larval control tools.

  12. Select small core structure carbamates exhibit high contact toxicity to "carbamate-resistant" strain malaria mosquitoes, Anopheles gambiae (Akron.

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    Dawn M Wong

    Full Text Available Acetylcholinesterase (AChE is a proven target for control of the malaria mosquito (Anopheles gambiae. Unfortunately, a single amino acid mutation (G119S in An. gambiae AChE-1 (AgAChE confers resistance to the AChE inhibitors currently approved by the World Health Organization for indoor residual spraying. In this report, we describe several carbamate inhibitors that potently inhibit G119S AgAChE and that are contact-toxic to carbamate-resistant An. gambiae. PCR-RFLP analysis was used to confirm that carbamate-susceptible G3 and carbamate-resistant Akron strains of An. gambiae carry wild-type (WT and G119S AChE, respectively. G119S AgAChE was expressed and purified for the first time, and was shown to have only 3% of the turnover number (k(cat of the WT enzyme. Twelve carbamates were then assayed for inhibition of these enzymes. High resistance ratios (>2,500-fold were observed for carbamates bearing a benzene ring core, consistent with the carbamate-resistant phenotype of the G119S enzyme. Interestingly, resistance ratios for two oxime methylcarbamates, and for five pyrazol-4-yl methylcarbamates were found to be much lower (4- to 65-fold. The toxicities of these carbamates to live G3 and Akron strain An. gambiae were determined. As expected from the enzyme resistance ratios, carbamates bearing a benzene ring core showed low toxicity to Akron strain An. gambiae (LC(50>5,000 μg/mL. However, one oxime methylcarbamate (aldicarb and five pyrazol-4-yl methylcarbamates (4a-e showed good to excellent toxicity to the Akron strain (LC(50 = 32-650 μg/mL. These results suggest that appropriately functionalized "small-core" carbamates could function as a resistance-breaking anticholinesterase insecticides against the malaria mosquito.

  13. Comparative mosquito repellency of essential oils against Aedes aegypti (Linn.), Anopheles dirus (Peyton and Harrison) and Culex quinquefasciatus (Say)

    Institute of Scientific and Technical Information of China (English)

    Siriporn Phasomkusolsil; Mayura Soonwera

    2011-01-01

    Objective: To assess the repellency to female Aedes aegypti (Ae. aegypti), Anopheles dirus (An. dirus) and Culex quinquefasciatus (Cx. quinquefasciatus) of seven essential oils using two treatment methods. Methods: Topical applications of three dose concentrations (0.02, 0.10 and 0.21 mg/cm2) were made on the forearms of volunteers. Dose-response study and protection time study were employed in the experiment. Results: In the dose-response test, Cymbopogon citratus (C. citratus), Cymbopogon nardus (C. nardus), Syzygium aromaticum (S. aromaticum) and Ocimum basilicum (O. basilicum) exhibited a high repellency against Ae. aegypti with ED50 at < 0.045 mg/cm2, whereas C. citratus, C. nardus and S. aromaticum showed repellency against An. dirus with ED50 at <0.068 mg/cm2. Furthermore, the essential oils of C. citratus, C. nardus, S. aromaticum, O.basilicum and Cananga odorata gave strong effective dose (ED 50) values at <0.003 mg/cm2 when tested against Cx. quinquefasciatus. For testing by arm in cage method, at 0.21 mg/cm2, protection time of C. citratus gave the longest lasting period against three mosquito species, 72 min for Ae. aegypti, 132 min for An. dirus and 84 min for Cx. quinquefasciatus. In addition, the two essential oils exhibited moderate repellency against Ae. aegypti, An. dirus and Cx. quinquefasciatus, at 60, 90 and 78 min with C. nardus, and 54, 96 and 72 min with S. aromaticum, respectively. Conclusions: The percentage repellency increased when the concentration of essential oils increased. In contrast, biting rates decreased when the concentration of essential oils increased.C. citratus exhibited high efficiency for the protection time and the percentage of biting deterrent against all of 3 mosquito species.

  14. A stable isotope dual-labelling approach to detect multiple insemination in un-irradiated and irradiated Anopheles arabiensis mosquitoes

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    Hood Rebecca C

    2008-04-01

    Full Text Available Abstract Background In the context of a Sterile Insect Technique programme, the occurrence of multiple insemination in the malaria mosquito Anopheles arabiensis Patton was studied using a novel labelling system with the stable isotopes 15N and 13C. The incidence of multiple insemination in the absence of radiation, and when males were irradiated in the pupal stage and competed against un-irradiated males were assessed. Males used in the experiments were labelled with either 15N or 13C and the label was applied to the larval rearing water. Males with either label and virgin females were caged at a 1:1:1 ratio. Males used in the radiation treatments were irradiated in the pupal stage with a partially or fully-sterilizing dose of 70 or 120 Gy, respectively. After mating, females were dissected and inseminated spermathecae analysed using mass spectrometry. Results The data indicate that about 25% of inseminated females had been inseminated multiply. The presence of irradiated males in the experiments did not affect the incidence of multiple insemination. In line with previous research, irradiated males were generally less competitive than un-irradiated males. Conclusion The implications of these findings for the Sterile Insect Technique are discussed, and further experiments recommended. The dual-labelling system used to determine paternity gave good results for 13C, however, for 15N it is recommended to increase the amount of label in future studies.

  15. A CRISPR-Cas9 gene drive system targeting female reproduction in the malaria mosquito vector Anopheles gambiae.

    Science.gov (United States)

    Hammond, Andrew; Galizi, Roberto; Kyrou, Kyros; Simoni, Alekos; Siniscalchi, Carla; Katsanos, Dimitris; Gribble, Matthew; Baker, Dean; Marois, Eric; Russell, Steven; Burt, Austin; Windbichler, Nikolai; Crisanti, Andrea; Nolan, Tony

    2016-01-01

    Gene drive systems that enable super-Mendelian inheritance of a transgene have the potential to modify insect populations over a timeframe of a few years. We describe CRISPR-Cas9 endonuclease constructs that function as gene drive systems in Anopheles gambiae, the main vector for malaria. We identified three genes (AGAP005958, AGAP011377 and AGAP007280) that confer a recessive female-sterility phenotype upon disruption, and inserted into each locus CRISPR-Cas9 gene drive constructs designed to target and edit each gene. For each targeted locus we observed a strong gene drive at the molecular level, with transmission rates to progeny of 91.4 to 99.6%. Population modeling and cage experiments indicate that a CRISPR-Cas9 construct targeting one of these loci, AGAP007280, meets the minimum requirement for a gene drive targeting female reproduction in an insect population. These findings could expedite the development of gene drives to suppress mosquito populations to levels that do not support malaria transmission. PMID:26641531

  16. A CRISPR-Cas9 gene drive system targeting female reproduction in the malaria mosquito vector Anopheles gambiae.

    Science.gov (United States)

    Hammond, Andrew; Galizi, Roberto; Kyrou, Kyros; Simoni, Alekos; Siniscalchi, Carla; Katsanos, Dimitris; Gribble, Matthew; Baker, Dean; Marois, Eric; Russell, Steven; Burt, Austin; Windbichler, Nikolai; Crisanti, Andrea; Nolan, Tony

    2016-01-01

    Gene drive systems that enable super-Mendelian inheritance of a transgene have the potential to modify insect populations over a timeframe of a few years. We describe CRISPR-Cas9 endonuclease constructs that function as gene drive systems in Anopheles gambiae, the main vector for malaria. We identified three genes (AGAP005958, AGAP011377 and AGAP007280) that confer a recessive female-sterility phenotype upon disruption, and inserted into each locus CRISPR-Cas9 gene drive constructs designed to target and edit each gene. For each targeted locus we observed a strong gene drive at the molecular level, with transmission rates to progeny of 91.4 to 99.6%. Population modeling and cage experiments indicate that a CRISPR-Cas9 construct targeting one of these loci, AGAP007280, meets the minimum requirement for a gene drive targeting female reproduction in an insect population. These findings could expedite the development of gene drives to suppress mosquito populations to levels that do not support malaria transmission.

  17. Mecanismos de invasión del esporozoíto de Plasmodium en el mosquito vector Anopheles

    Directory of Open Access Journals (Sweden)

    Lilian M. Spencer

    2016-09-01

    Full Text Available La Malaria o Paludismo es una de las enfermedades tropicales considerada un problema de salud pública a nivel mundial por la OMS. Plasmodium es un protozoario cuyo vector es la hembra del mosquito Anopheles. En este vector se cumplen dos procesos fundamentales en el ciclo de vida del parásito, como son la reproducción sexual, con la formación de un cigoto móvil llamado ooquineto como producto de la fertilización entre los gametos; y la invasión del epitelio del estómago y formación del ooquiste. El estadio producto de esta esporogonia son los esporozoítos (reproducción asexual que se dirigen a las glándulas salivales; y es el infectivo para el mamífero. El esporozoíto es el responsable de establecer la enfermedad en su hospedador vertebrado y por lo tanto los procesos de invasión de este a las glándulas salivales del mosquito es uno de los puntos fundamentales de estudio. Nosotros presentamos una revisión acerca de los mecanismos de invasión del parásito dentro del vector mosquito y las proteínas más importantes que median este proceso. Uno de los aspectos más estudiados en las investigaciones en malaria ha sido determinar la antigenicidad de dichas proteínas en esta parte del ciclo con el fin de ser usadas en el diseño de vacunas. Entre ellas, algunas de las más estudiadas son: P230, P48/45, P28, P25, CTRP, CS, TRAP, WARP y SOAP las cuales han sido consideradas en las estrategias para inhibir el desarrollo del parásito, mejor conocidas como vacunas de bloqueo de trasmisión por el vector. Por lo tanto, presentamos algunas de las estrategias en el diseño de vacunas, basado en las proteínas implicadas en los estadios desarrollados dentro del vector.

  18. Apolipophorin-III mediates antiplasmodial epithelial responses in Anopheles gambiae (G3 mosquitoes.

    Directory of Open Access Journals (Sweden)

    Lalita Gupta

    Full Text Available BACKGROUND: Apolipophorin-III (ApoLp-III is known to play an important role in lipid transport and innate immunity in lepidopteran insects. However, there is no evidence of involvement of ApoLp-IIIs in the immune responses of dipteran insects such as Drosophila and mosquitoes. METHODOLOGY/PRINCIPAL FINDINGS: We report the molecular and functional characterization of An. gambiae apolipophorin-III (AgApoLp-III. Mosquito ApoLp-IIIs have diverged extensively from those of lepidopteran insects; however, the predicted tertiary structure of AgApoLp-III is similar to that of Manduca sexta (tobacco hornworm. We found that AgApoLp-III mRNA expression is strongly induced in the midgut of An. gambiae (G3 strain mosquitoes in response to Plasmodium berghei infection. Furthermore, immunofluorescence stainings revealed that high levels of AgApoLp-III protein accumulate in the cytoplasm of Plasmodium-invaded cells and AgApoLp-III silencing increases the intensity of P. berghei infection by five fold. CONCLUSION: There are broad differences in the midgut epithelial responses to Plasmodium invasion between An. gambiae strains. In the G3 strain of An. gambiae AgApoLp-III participates in midgut epithelial defense responses that limit Plasmodium infection.

  19. Apolipophorin-III Mediates Antiplasmodial Epithelial Responses in Anopheles gambiae (G3) Mosquitoes

    Science.gov (United States)

    Jo, Yong Hun; Oh, Seung Han; Kumar, Sanjeev; Noh, Mi Young; Lee, Yong Seok; Cha, Sung-Jae; Seo, Sook Jae; Kim, Iksoo; Han, Yeon Soo; Barillas-Mury, Carolina

    2010-01-01

    Background Apolipophorin-III (ApoLp-III) is known to play an important role in lipid transport and innate immunity in lepidopteran insects. However, there is no evidence of involvement of ApoLp-IIIs in the immune responses of dipteran insects such as Drosophila and mosquitoes. Methodology/Principal Findings We report the molecular and functional characterization of An. gambiae apolipophorin-III (AgApoLp-III). Mosquito ApoLp-IIIs have diverged extensively from those of lepidopteran insects; however, the predicted tertiary structure of AgApoLp-III is similar to that of Manduca sexta (tobacco hornworm). We found that AgApoLp-III mRNA expression is strongly induced in the midgut of An. gambiae (G3 strain) mosquitoes in response to Plasmodium berghei infection. Furthermore, immunofluorescence stainings revealed that high levels of AgApoLp-III protein accumulate in the cytoplasm of Plasmodium-invaded cells and AgApoLp-III silencing increases the intensity of P. berghei infection by five fold. Conclusion There are broad differences in the midgut epithelial responses to Plasmodium invasion between An. gambiae strains. In the G3 strain of An. gambiae AgApoLp-III participates in midgut epithelial defense responses that limit Plasmodium infection. PMID:21072214

  20. Larvicidal activity of Saraca indica, Nyctanthes arbor-tristis, and Clitoria ternatea extracts against three mosquito vector species.

    Science.gov (United States)

    Mathew, Nisha; Anitha, M G; Bala, T S L; Sivakumar, S M; Narmadha, R; Kalyanasundaram, M

    2009-04-01

    Screening of natural products for mosquito larvicidal activity against three major mosquito vectors Aedes aegypti, Culex quinquefasciatus, and Anopheles stephensi resulted in the identification of three potential plant extracts viz., Saraca indica/asoca, Nyctanthes arbor-tristis, and Clitoria ternatea for mosquito larval control. In the case of S. indica/asoca, the petroleum ether extract of the leaves and the chloroform extract of the bark were effective against the larvae of C. quinquefasciatus with respective LC(50) values 228.9 and 291.5 ppm. The LC(50) values of chloroform extract of N. arbor-tristis leaves were 303.2, 518.2, and 420.2 ppm against A. aegypti, A. stephensi, and C. quinquefasciatus, respectively. The methanol and chloroform extracts of flowers of N. arbor-tristis showed larvicidal activity against larvae of A. stephensi with the respective LC(50) values of 244.4 and 747.7 ppm. Among the methanol extracts of C. ternatea leaves, roots, flowers, and seeds, the seed extract was effective against the larvae of all the three species with LC(50) values 65.2, 154.5, and 54.4 ppm, respectively, for A. stephensi, A. aegypti, and C. quinquefasciatus. Among the three plant species studied for mosquito larvicidal activity, C. ternatea was showing the most promising mosquito larvicidal activity. The phytochemical analysis of the promising methanolic extract of the seed extract was positive for carbohydrates, saponins, terpenoids, tannins, and proteins. In conclusion, bioassay-guided fractionation of effective extracts may result in identification of a useful molecule for the control of mosquito vectors. PMID:19039604

  1. Genetic diversity in two sibling species of the Anopheles punctulatus group of mosquitoes on Guadalcanal in the Solomon Islands

    Science.gov (United States)

    2008-01-01

    Background The mosquito Anopheles irenicus, a member of the Anopheles punctulatus group, is geographically restricted to Guadalcanal in the Solomon Islands. It shows remarkable morphological similarities to one of its sibling species, An. farauti sensu stricto (An. farauti s.s.), but is dissimilar in host and habitat preferences. To infer the genetic variations between these two species, we have analyzed mitochondrial cytochrome oxidase subunit II (COII) and nuclear ribosomal internal transcribed spacer 2 (ITS2) sequences from Guadalcanal and from one of its nearest neighbours, Malaita, in the Solomon Islands. Results An. farauti s.s. was collected mostly from brackish water and by the human bait method on both islands, whereas An. irenicus was only collected from fresh water bodies on Guadalcanal Island. An. irenicus is distributed evenly with An. farauti s.s. (ΦSC = 0.033, 0.38%) and its range overlaps in three of the seven sampling sites. However, there is a significant population genetic structure between the species (ΦCT = 0.863, P < 0.01; ΦST = 0.865, P < 0.01 and FST = 0.878, P < 0.01). Phylogenetic analyses suggest that An. irenicus is a monophyletic species, not a hybrid, and is closely related to the An. farauti s.s. on Guadalcanal. The time estimator suggests that An. irenicus diverged from the ancestral An. farauti s.s. on Guadalcanal within 29,000 years before present (BP). An. farauti s.s. expanded much earlier on Malaita (texp = 24,600 BP) than the populations on Guadalcanal (texp = 16,800 BP for An. farauti s.s. and 14,000 BP for An. irenicus). Conclusion These findings suggest that An. irenicus and An. farauti s.s. are monophyletic sister species living in sympatry, and their populations on Guadalcanal have recently expanded. Consequently, the findings further suggest that An. irenicus diverged from the ancestral An. farauti s.s. on Guadalcanal. PMID:19025663

  2. Spatial repellency of transfluthrin-treated hessian strips against laboratory-reared Anopheles arabiensis mosquitoes in a semi-field tunnel cage

    Directory of Open Access Journals (Sweden)

    Ogoma Sheila B

    2012-03-01

    Full Text Available Abstract Background Vapour phase spatial repellents deter mosquitoes from attacking one or more humans in a protected space. Simulation models indicate that high coverage of spatial repellents can enhance the impact of long - lasting insecticide nets (LLINs and indoor residual spraying (IRS where mosquito vectors commonly bite humans outdoors. Here we report a preliminary evaluation of an effective, user-friendly prototype product for delivering spatial repellents to protect against malaria vector mosquitoes. Findings Protective efficacy of a 4.0 × 0.3 m strip of hessian sacking treated with 10 ml of transfluthrin was evaluated in a 60 m × 2 m ×2.5 m netting tunnel with malaria-free insectary-reared Anopheles arabiensis Patton mosquitoes. Personal protection, in terms of proportional reduction of exposure to bites, was measured by comparing human landing catches of volunteers with treated and untreated strips. A freshly treated hessian strip reduced mosquito attack rate on human volunteers by > 99% and consistently conferred > 90% protective efficacy for a period of 6 months. Over the entire study period, only 22 out of 1400 released mosquitoes bit volunteers using the treated sacking strip while 894 out of 1400 mosquitoes released into cages containing volunteers using an untreated strip fed upon them. Conclusion Locally available natural fibers may be promising absorbent substrates for delivering spatial repellents, such as transfluthrin, to protect against mosquitoes in tropical settings. However, these observations relate to a single prototype specimen of this particular device, therefore, much more detailed, well replicated studies are essential to establish long-term efficacy, effectiveness, practicability and affordability.

  3. Ammonium sulphate fertiliser increases larval populations of Anopheles arabiensis and culicine mosquitoes in rice fields

    DEFF Research Database (Denmark)

    Mutero, C M; Ng'ang'a, P N; Wekoyela, P;

    2004-01-01

    Field experiments were conducted in central Kenya, to study the effect of ammonium sulphate fertiliser ((NH(4))(2)SO(4)) on mosquito larval populations in rice fields. The experiments used a complete randomised block design having four blocks with two experimental ponds per block, and the fertili......Field experiments were conducted in central Kenya, to study the effect of ammonium sulphate fertiliser ((NH(4))(2)SO(4)) on mosquito larval populations in rice fields. The experiments used a complete randomised block design having four blocks with two experimental ponds per block......, and the fertiliser and control treatments allocated randomly among the ponds. Student's two-sample unpaired t-test was used to test for the significance of differences between the relative counts of larvae in fertiliser and control treatments. The results showed a significant overall increase in the larval...... populations of An. arabiensis (Pfertiliser. Significantly more fourth instar larvae of An. arabiensis were collected in fertiliser than control plots (Pfertiliser application had...

  4. Life on the edge: African malaria mosquito (Anopheles gambiae s. l.) larvae are amphibious

    Science.gov (United States)

    Miller, James R.; Huang, Juan; Vulule, John; Walker, Edward D.

    2007-03-01

    Anopheles gambiae s.l. is the main vector of malaria in Sub-Saharan Africa. Here, an estimated 1 million people die every year from this disease. Despite considerable research on An. gambiae that increasingly explores sub-organismal phenomena, important facets of the field biology of this deadly insect are yet being discovered. In the current study, we used simple observational tools to reveal that the habitat of larval An. gambiae is not limited within the boundaries of temporary mud puddles, as has been the accepted generalization. Thus, control tactics aimed at immatures must consider zones larger than puddles per se. In fact, eggs are more likely to be found outside than inside puddles. Eggs can develop and larvae can emerge on mud. Larvae are then capable of three distinct modes of terrestrial displacement (two active and one passive), whereby, they can reach standing water. On mud bearing a film of water, larvae actively displace backwards by sinusoidal undulations shown to be only a slight variation of the swimming motor program. On drying mud, larvae switch to a slower and forward form of active locomotion resembling that of a crawling caterpillar. During rains, small larvae may be passively displaced by flowing rainwater so as to be deposited into puddles. These capabilities for being amphibious, along with very rapid growth and development, help explain how An. gambiae thrives in a highly uncertain and often hostile larval environment.

  5. Evidence of carbamate resistance in urban populations of Anopheles gambiae s.s. mosquitoes resistant to DDT and deltamethrin insecticides in Lagos, South-Western Nigeria

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    Oduola Adedayo O

    2012-06-01

    Full Text Available Abstract Background Resistance monitoring is essential in ensuring the success of insecticide based vector control programmes. This study was carried out to assess the susceptibility status of urban populations of Anopheles gambiae to carbamate insecticide being considered for vector control in mosquito populations previously reported to be resistant to DDT and permethrin. Methods Two – three day old adult female Anopheles mosquitoes reared from larval collections in 11 study sites from Local Government Areas of Lagos were exposed to test papers impregnated with DDT 4%, deltamethrin 0.05% and propoxur 0.1% insecticides. Additional tests were carried out to determine the susceptibility status of the Anopheles gambiae population to bendiocarb insecticide. Members of the A. gambiae complex, the molecular forms, were identified by PCR assays. The involvement of metabolic enzymes in carbamate resistance was assessed using Piperonyl butoxide (PBO synergist assays. The presence of kdr-w/e and ace-1R point mutations responsible for DDT-pyrethroid and carbamate resistance mechanisms was also investigated by PCR. Results Propoxur resistance was found in 10 out of the 11 study sites. Resistance to three classes of insecticides was observed in five urban localities. Mortality rates in mosquitoes exposed to deltamethrin and propoxur did not show any significant difference (P > 0.05 but was significantly higher (P A. gambiae s.s (M form. The kdr -w point mutation at allelic frequencies between 45%-77% was identified as one of the resistant mechanisms responsible for DDT and pyrethroid resistance. Ace-1R point mutation was absent in the carbamate resistant population. However, the possible involvement of metabolic resistance was confirmed by synergistic assays conducted. Conclusion Evidence of carbamate resistance in A. gambiae populations already harbouring resistance to DDT and permethrin is a clear indication that calls for the implementation of

  6. Next-generation site-directed transgenesis in the malaria vector mosquito Anopheles gambiae: self-docking strains expressing germline-specific phiC31 integrase.

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    Janet M Meredith

    Full Text Available Diseases transmitted by mosquitoes have a devastating impact on global health and the situation is complicated due to difficulties with both existing control measures and the impact of climate change. Genetically modified mosquitoes that are refractory to disease transmission are seen as having great potential in the delivery of novel control strategies. The Streptomyces phage phiC31 integrase system has been successfully adapted for site-directed transgene integration in a range of insects, thus overcoming many limitations due to size constraints and random integration associated with transposon-mediated transformation. Using this technology, we previously published the first site-directed transformation of Anopheles gambiae, the principal vector of human malaria. Mosquitoes were initially engineered to incorporate the phiC31 docking site at a defined genomic location. A second phase of genetic modification then achieved site-directed integration of an anti-malarial effector gene. In the current publication we report improved efficiency and utility of the phiC31 integrase system following the generation of Anopheles gambiae self-docking strains. Four independent strains, with docking sites at known locations on three different chromosome arms, were engineered to express integrase under control of the regulatory regions of the nanos gene from Anopheles gambiae. The resulting protein accumulates in the posterior oocyte to provide integrase activity at the site of germline development. Two self-docking strains, exhibiting significantly different levels of integrase expression, were assessed for site-directed transgene integration and found to demonstrate greatly improved survival and efficiency of transformation. In the fight against malaria, it is imperative to establish a broad repertoire of both anti-malarial effector genes and tissue-specific promoters to regulate their expression, enabling those offering maximum effect with minimum fitness

  7. Comparative genomic analysis of chitinase and chitinase-like genes in the African malaria mosquito (Anopheles gambiae.

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    Jianzhen Zhang

    Full Text Available Chitinase is an important enzyme responsible for chitin metabolism in a wide range of organisms including bacteria, yeasts and other fungi, nematodes and arthropods. However, current knowledge on chitinolytic enzymes, especially their structures, functions and regulation is very limited. In this study we have identified 20 chitinase and chitinase-like genes in the African malaria mosquito, Anopheles gambiae, through genome-wide searching and transcript profiling. We assigned these genes into eight different chitinase groupings (groups I-VIII. Domain analysis of their predicted proteins showed that all contained at least one catalytic domain. However, only seven (AgCht4, AgCht5-1, AgCht6, AgCht7, AgCht8, AgCht10 and AgCht23 displayed one or more chitin-binding domains. Analyses of stage- and tissue-specific gene expression revealed that most of these genes were expressed in larval stages. However, AgCht8 was mainly expressed in the pupal and adult stages. AgCht2 and AgCht12 were specifically expressed in the foregut, whereas AgCht13 was only expressed in the midgut. The high diversity and complexity of An. gambiae chitinase and chitinase-like genes suggest their diverse functions during different developmental stages and in different tissues of the insect. A comparative genomic analysis of these genes along with those present in Drosophila melanogaster, Tribolium castaneum and several other insect species led to a uniform classification and nomenclature of these genes. Our investigation also provided important information for conducting future studies on the functions of chitinase and chitinase-like genes in this important malaria vector and other species of arthropods.

  8. Chromosome inversions, genomic differentiation and speciation in the African malaria mosquito Anopheles gambiae.

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    Yoosook Lee

    Full Text Available The African malaria vector, Anopheles gambiae, is characterized by multiple polymorphic chromosomal inversions and has become widely studied as a system for exploring models of speciation. Near complete reproductive isolation between different inversion types, known as chromosomal forms, has led to the suggestion that A. gambiae is in early stages of speciation, with divergence evolving in the face of considerable gene flow. We compared the standard chromosomal arrangement (Savanna form with genomes homozygous for j, b, c, and u inversions (Bamako form in order to identify regions of genomic divergence with respect to inversion polymorphism. We found levels of divergence between the two sub-taxa within some of these inversions (2Rj and 2Rb, but at a level lower than expected and confined near the inversion breakpoints, consistent with a gene flux model. Unexpectedly, we found that the majority of diverged regions were located on the X chromosome, which contained half of all significantly diverged regions, with much of this divergence located within exons. This is surprising given that the Bamako and Savanna chromosomal forms are both within the S molecular form that is defined by a locus near centromere of X chromosome. Two X-linked genes (a heat shock protein and P450 encoding genes involved in reproductive isolation between the M and S molecular forms of A. gambiae were also significantly diverged between the two chromosomal forms. These results suggest that genes mediating reproductive isolation are likely located on the X chromosome, as is thought to be the case for the M and S molecular forms. We conclude that genes located on the sex chromosome may be the major force driving speciation between these chromosomal forms of A. gambiae.

  9. 传疟按蚊抗药性研究进展%Research advance on insecticide resistance of malaria vector mosquito Anopheles

    Institute of Scientific and Technical Information of China (English)

    秦茜; 闫桂云; 陈晓光

    2014-01-01

    In May 2010,the Ministry of Health and Chinese Government issued Action Plan of China Malaria Elimination (2010-2020),aiming at complete elimination of malaria in P.R.China by 2020.Vector control is a fundamental element of the existing global strategy to fight malaria.Anopheles is the main malaria vector mosquito.However,rapidly increasing insecticide resistance of mosquitoes threatens current malaria vector control efforts.In order to understand current status of mosquito resistance to insecticide and resistance mechanisms of the malaria vector,the current status of insecticide resistance in malaria vector mosquito Anopheles,the resistance mechanisms and the detection methods on resistance were reviewed in this paper.%我国卫生部于2010年5月印发《中国消除疟疾行动计划(2010-2020年)》,提出在2020年,将全面彻底消除疟疾.控制及消除疟疾的关键在于传播媒介的控制,而按蚊为疟疾主要传播媒介,传疟媒介对杀虫剂的抗药性直接导致了疟疾发病的死灰复燃.为了全面了解疟疾蚊媒的抗药性现状和产生机制,该文对国内外传疟按蚊抗药性现状、产生机制和检测方法进行综述.

  10. Potential topical natural repellent against Ae. aegypti, Culex sp. and Anopheles sp. mosquitoes

    Directory of Open Access Journals (Sweden)

    Dewi Nur Hodijah

    2014-08-01

    Full Text Available AbstrakLatar belakang:Minyak atsiri daun sirih diketahui mempunyai daya proteksi. Dibuatkan losion berdasarkan pengantar sediaan farmasi yang ditambahkan minyak atsiri daun nilam. Sediaan losion dipilih agar dapat menempel lebih lama di permukaan kulit. Tujuan penelitian ini untuk membandingkan daya proteksi antara losion dengan penambahan minyak nilam dan losion tanpa penambahan minyak nilam dibandingkan daya proteksi dengan DEET. Metode: Penelitian ini merupakan penelitian eksperimental laboratorium. Semua nyamuk uji berasal dari insektarium laboratorium penelitian kesehatan Loka litbang P2B2 Ciamis. Konsentrasi minyak atsiri daun sirih dalam losion adalah 4%; konsentrasi minyak nilam sebagai zat pengikat adalah 0,4%. Formula yang digunakan yaitu formula dasar yang ada pada pengantar sediaan farmasi. Uji repelensi dilakukan dengan menggunakan metoda yang direkomendasikan oleh Komisi pestisida.Hasil: Dihasilkan formulasi losion yang stabil dan masih memenuhi standar formulasi sediaan. Berdasarkan hasil, diperoleh data bahwa DEET dan losion hasil modifikasi memiliki rata-rata daya proteksi di atas 90% selama 6 jam terhadap nyamuk Ae.aegypti dan Culex sp. Kesimpulan: Penambahan minyak nilam pada losion sirih dapat meningkatkan daya proteksi terhadap hinggapan nyamuk Ae. aegypti dan Culex sp. (Health Science Indones 2014;1:44-8Kata kunci:repelen alamiah, minyak atsiri, daun sirih, daun nilam, Ae. aegypti, Culex sp.AbstractBackground: Betel leaf essential oil lotion has been known to have insect repellent properties. A lotion was made based on a pharmaceutical formula from a monograph where patchouli leaf essential oil was added. A lotion preparation was intended to enhance adherence of the formula on the surface of the skin. The purpose of this study was to compare protection percentage of lotion with patchouli oil and without patchouli oil lotion compared to DEET.Methods: This study is an experimental laboratory-based research. All mosquitoes

  11. Potential mosquito repellent compounds of Ocimum species against 3N7H and 3Q8I of Anopheles gambiae

    OpenAIRE

    Gaddaguti, Venugopal; Venkateswara Rao, Talluri; Prasada Rao, Allu

    2016-01-01

    Mosquitoes are exceptionally efficient in detecting their hosts for blood meal using odorant binding proteins, viz. 3N7H and 3Q8I and spread several dreadful diseases. DEET is a synthetic mosquito repellent widely used all over world for protection against mosquito bite. Reports reveal that, synthetic mosquito repellents may pose health problems in considerably large population. In view of the above fact, we made an attempt to discover efficient and novel natural mosquito repellent compounds ...

  12. Deep sequencing revealed molecular signature of horizontal gene transfer of plant like transcripts in the mosquito Anopheles culicifacies: an evolutionary puzzle [version 1; referees: 2 approved

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    Punita Sharma

    2015-12-01

    Full Text Available In prokaryotes, horizontal gene transfer (HGT has been regarded as an important evolutionary drive to acquire and retain beneficial genes for their survival in diverse ecologies. However, in eukaryotes, the functional role of HGTs remains questionable, although current genomic tools are providing increased evidence of acquisition of novel traits within non-mating metazoan species. Here, we provide another transcriptomic evidence for the acquisition of massive plant genes in the mosquito, Anopheles culicifacies. Our multiple experimental validations including genomic PCR, RT-PCR, real-time PCR, immuno-blotting and immuno-florescence microscopy, confirmed that plant like transcripts (PLTs are of mosquito origin and may encode functional proteins. A comprehensive molecular analysis of the PLTs and ongoing metagenomic analysis of salivary microbiome provide initial clues that mosquitoes may have survival benefits through the acquisition of nuclear as well as chloroplast encoded plant genes. Our findings of PLTs further support the similar questionable observation of HGTs in other higher organisms, which is still a controversial and debatable issue in the community of evolutionists. We believe future understanding of the underlying mechanism of the feeding associated molecular responses may shed new insights in the functional role of PLTs in the mosquito.

  13. The vasa regulatory region mediates germline expression and maternal transmission of proteins in the malaria mosquito Anopheles gambiae: a versatile tool for genetic control strategies

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    Burt Austin

    2009-07-01

    Full Text Available Abstract Background Germline specific promoters are an essential component of potential vector control strategies which function by genetic drive, however suitable promoters are not currently available for the main human malaria vector Anopheles gambiae. Results We have identified the Anopheles gambiae vasa-like gene and found its expression to be specifically localized to both the male and female gonads in adult mosquitoes. We have functionally characterised using transgenic reporter lines the regulatory regions required for driving transgene expression in a pattern mirroring that of the endogenous vasa locus. Two reporter constructs indicate the existence of distinct vasa regulatory elements within the 5' untranslated regions responsible not only for the spatial and temporal but also for the sex specific germline expression. vasa driven eGFP expression in the ovary of heterozygous mosquitoes resulted in the progressive accumulation of maternal protein and transcript in developing oocytes that were then detectable in all embryos and neonatal larvae. Conclusion We have characterized the vasa regulatory regions that are not only suited to drive transgenes in the early germline of both sexes but could also be utilized to manipulate the zygotic genome of developing embryos via maternal deposition of active molecules. We have used computational models to show that a homing endonuclease-based gene drive system can function in the presence of maternal deposition and describe a novel non-invasive control strategy based on early vasa driven homing endonuclease expression.

  14. Unravelling the Evolution of the Allatostatin-Type A, KISS and Galanin Peptide-Receptor Gene Families in Bilaterians: Insights from Anopheles Mosquitoes.

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    Rute C Felix

    Full Text Available Allatostatin type A receptors (AST-ARs are a group of G-protein coupled receptors activated by members of the FGL-amide (AST-A peptide family that inhibit food intake and development in arthropods. Despite their physiological importance the evolution of the AST-A system is poorly described and relatively few receptors have been isolated and functionally characterised in insects. The present study provides a comprehensive analysis of the origin and comparative evolution of the AST-A system. To determine how evolution and feeding modified the function of AST-AR the duplicate receptors in Anopheles mosquitoes, were characterised. Phylogeny and gene synteny suggested that invertebrate AST-A receptors and peptide genes shared a common evolutionary origin with KISS/GAL receptors and ligands. AST-ARs and KISSR emerged from a common gene ancestor after the divergence of GALRs in the bilaterian genome. In arthropods, the AST-A system evolved through lineage-specific events and the maintenance of two receptors in the flies and mosquitoes (Diptera was the result of a gene duplication event. Speciation of Anopheles mosquitoes affected receptor gene organisation and characterisation of AST-AR duplicates (GPRALS1 and 2 revealed that in common with other insects, the mosquito receptors were activated by insect AST-A peptides and the iCa2+-signalling pathway was stimulated. GPRALS1 and 2 were expressed mainly in mosquito midgut and ovaries and transcript abundance of both receptors was modified by feeding. A blood meal strongly up-regulated expression of both GPRALS in the midgut (p < 0.05 compared to glucose fed females. Based on the results we hypothesise that the AST-A system in insects shared a common origin with the vertebrate KISS system and may also share a common function as an integrator of metabolism and reproduction.AST-A and KISS/GAL receptors and ligands shared common ancestry prior to the protostome-deuterostome divergence. Phylogeny and gene

  15. 3-Oxoisoxazole-2(3H)-carboxamides and isoxazol-3-yl carbamates: Resistance-breaking acetylcholinesterase inhibitors targeting the malaria mosquito, Anopheles gambiae

    Science.gov (United States)

    Verma, Astha; Wong, Dawn M.; Islam, Rafique; Tong, Fan; Ghavami, Maryam; Mutunga, James M.; Slebodnick, Carla; Li, Jianyong; Viayna, Elisabet; Lam, Polo C.-H.; Totrov, Maxim M.; Bloomquist, Jeffrey R.; Carlier, Paul R.

    2015-01-01

    To identify potential selective and resistance-breaking mosquitocides against the African malaria vector Anopheles gambiae, we investigated the acetylcholinesterase (AChE) inhibitory and mosquitocidal properties of isoxazol-3-yl dimethylcarbamates (15), and the corresponding 3-oxoisoxazole-2(3H)-dimethylcarboxamide isomers (14). In both series, compounds were found with excellent contact toxicity to wild-type susceptible (G3) strain and multiply resistant (Akron) strain mosquitoes that carry the G119S resistance mutation of AChE. Compounds possessing good to excellent toxicity to Akron strain mosquitoes inhibit the G119S mutant of An. gambiae AChE (AgAChE) with ki values at least 10- to 600-fold higher than that of propoxur, a compound that does not kill Akron mosquitoes at the highest concentration tested. On average, inactivation of WT AgAChE by dimethylcarboxamides 14 was 10-20 fold faster than that of the corresponding isoxazol-3-yl dimethylcarbamates 15. X-ray crystallography of dimethylcarboxamide 14d provided insight into that reactivity, a finding that may explain the inhibitory power of structurally-related inhibitors of hormone-sensitive lipase. Finally, human/An. gambiae AChE inhibition selectivities of these compounds were low, suggesting the need for additional structural modification. PMID:25684426

  16. Combining two-dimensional gel electrophoresis and metabolomic data in support of dry-season survival in the two main species of the malarial mosquito Anopheles gambiae

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    Hidalgo K.

    2015-12-01

    Full Text Available In dry savannahs of West-Africa, the malarial mosquitoes of the Anopheles gambiae sensu stricto complex annually survive the harsh desiccating conditions of the dry season. However, the physiological and biochemical mechanisms underlying how these mosquitoes survive such desiccating conditions are still undefined, and controversial. In this context, we provide the first work examining both proteomic and metabolomic changes in the two molecular forms of A. gambiae s.s (M and S forms experimentally exposed to the rainy and dry season conditions as they experience in the field. Protein abundances of the mosquitoes were measured using a two-dimensional fluorescence difference gel electrophoresis (2D DIGE coupled with a matrix-assisted laser desorption/ionisation-time of flight (MALDI-TOF and tandem mass spectrometry (MS for protein identification. These assays were conducted by Applied Biomics (http://www.appliedbiomics.com, Applied Biomics, Inc. Hayward, CA, USA, and the mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium (http://proteomecentral.proteomexchange.org via the PRIDE partner repository with the dataset identifier PXD000294. The metabolomic analysis was conducted using both Acquity UPLC® system (for amino acid identification, and a gas-chromatography-mass spectrometry platform (for sugars identification. Metabolomic fingerprintings were assessed in the University of Rennes 1, UMR CNRS 6553 EcoBio (France. A detailed interpretation of the obtained data can be found in Hidalgo et al. (2014 [1] (Journal of Insect Physiology (2014.

  17. Cymbopogon citratus-synthesized gold nanoparticles boost the predation efficiency of copepod Mesocyclops aspericornis against malaria and dengue mosquitoes.

    Science.gov (United States)

    Murugan, Kadarkarai; Benelli, Giovanni; Panneerselvam, Chellasamy; Subramaniam, Jayapal; Jeyalalitha, Tirupathi; Dinesh, Devakumar; Nicoletti, Marcello; Hwang, Jiang-Shiou; Suresh, Udaiyan; Madhiyazhagan, Pari

    2015-06-01

    Plant-borne compounds can be employed to synthesize mosquitocidal nanoparticles that are effective at low doses. However, how they affect the activity of mosquito predators in the aquatic environment is unknown. In this study, we synthesized gold nanoparticles (AuN) using the leaf extract of Cymbopogon citratus, which acted as a reducing and capping agent. AuN were characterized by a variety of biophysical methods and sorted for size in order to confirm structural integrity. C. citratus extract and biosynthesized AuN were tested against larvae and pupae of the malaria vector Anopheles stephensi and the dengue vector Aedes aegypti. LC₅₀ of C. citratus extract ranged from 219.32 ppm to 471.36 ppm. LC₅₀ of AuN ranged from 18.80 ppm to 41.52 ppm. In laboratory, the predatory efficiency of the cyclopoid crustacean Mesocyclops aspericornis against A. stephensi larvae was 26.8% (larva I) and 17% (larva II), while against A. aegypti was 56% (I) and 35.1% (II). Predation against late-instar larvae was minimal. In AuN-contaminated environment,predation efficiency against A. stephensi was 45.6% (I) and 26.7% (II), while against A. aegypti was 77.3% (I) and 51.6% (II). Overall, low doses of AuN may help to boost the control of Anopheles and Aedes larval populations in copepod-based control programs.

  18. Evaluation of larvicidal activity of Pongamia pinnata extracts against three mosquito vectors

    Science.gov (United States)

    Kolli, Guna Ranjan; Balakrishnan; Vijayan; Sundararajan, Raja

    2013-01-01

    Objective To evaluate the mosquito larvicidal activity of Pongamia pinnata (P. pinnata) extracts against three mosquito vectors. Methods The methanol and hydroalcohol extracts of bark part of P. pinnata L were tested against fourth instar larvae of Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi. The mortality was observed 24 h and 48 h after treatment, data was subjected to probit analysis to determine lethal concentration (LC50 and LC90) to kill 50 and 90 percent of treated larvae of tested species. Results The larval mortality was found in both methanol and hydroalcohol extracts of P. pinnata against Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi with LC50 values of 84.8, 118.2 and 151.7 ppm; 97.7, 128.3 and 513 ppm. The highest larval mortality was found in methanol extract of P. pinnata when comparable to the hydroalcohol extract. Conclusions These results suggest that both methanol and hyrdoalcohol extracts have the potential to be used as an ideal ecofriendly approach for the control of disease vectors. This could lead to isolation of novel natural larvicidal compounds.

  19. Evaluation of larvicidal activity of Pongamia pinnata extracts against three mosquito vectors

    Institute of Scientific and Technical Information of China (English)

    Guna Ranjan Kolli; Balakrishnan; Vijayan; Raja Sundararajan

    2013-01-01

    Objective: To evaluate the mosquito larvicidal activity of Pongamia pinnata (P. pinnata) extracts against three mosquito vectors.Methods:The larval mortality was found in both methanol and hydroalcohol extracts of P. pinnata against fourth instar larvae of Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi. The mortality was observed 24 h and 48 h after treatment, data was subjected to probit analysis to determine lethal concentration (LC50 and LC90) to kill 50 and 90 percent of treated larvae of tested species.Results:The methanol and hydroalcohol extracts of bark part of P. pinnata L were tested against Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi with LC50 values of 84.8, 118.2 and 151.7 ppm; 97.7, 128.3 and 513 ppm. The highest larval mortality was found in methanol extract of P. pinnata when comparable to the hydroalcohol extract.Conclusions:These results suggest that both methanol and hyrdoalcohol extracts have the potential to be used as an ideal ecofriendly approach for the control of disease vectors. This could lead to isolation of novel natural larvicidal compounds.

  20. Characterization of larval habitats for anopheline mosquitoes in a malarious area under elimination program in the southeast of Iran

    Institute of Scientific and Technical Information of China (English)

    Moussa Soleimani-Ahmadi; Hassan Vatandoost; Mehdi Zare

    2014-01-01

    Objective: To determine the effects of environmental characteristics of larval habitats on distribution and abundance of anopheline mosquitoes in Bashagard county, a malarious area in southeast of Iran. Methods: Larvae were collected monthly using the standard dipping method and identified using a morphological-based key. Environmental characteristics of the larval habitats were recorded. Water samples were taken from habitats during larval collection for physico-chemical characterization. Statistical analyses were performed. Results: In total 5150 anopheline larvae from 36 larval habitats were collected and identified. They comprised of six species: Anopheles culicifacies (29.36%), Anopheles moghulensis (25.20%),Anopheles dthali stephensi (5.01%). (18.02%), Anopheles superpictus (17.24%), Anopheles turkhudi (5.17%) and Anopheles The most common larval habitats were natural and clear water bodies such as riverbeds with sandy substrates and still water. Furthermore, the anopheline larvae were abundant in permanent and full sunlight habitats without vegetation and algae. Larval density was positively correlated with water temperature. Chemical characteristics including conductivity, total alkalinity, sulphate and chloride had significant effects on distribution and abundance of anopheline species.Conclusions:The result of this study indicates a correlation between some environmental characteristics and anopheline larvae abundance which can be considered for effective planning and implementing malaria elimination program in Iran.

  1. Larvicidal activity of few select indigenous plants of North East India against disease vector mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Dohutia, C; Bhattacharyya, D R; Sharma, S K; Mohapatra, P K; Bhattacharjee, K; Gogoi, K; Gogoi, P; Mahanta, J; Prakash, A

    2015-03-01

    Mosquitoes are the vectors of several life threatening diseases like dengue, malaria, Japanese encephalitis and lymphatic filariasis, which are widely present in the north-eastern states of India. Investigations on five local plants of north-east India, selected on the basis of their use by indigenous communities as fish poison, were carried out to study their mosquito larvicidal potential against Anopheles stephensi (malaria vector), Stegomyia aegypti (dengue vector) and Culex quinquefasciatus (lymphatic filariasis vector) mosquitoes. Crude Petroleum ether extracts of the roots of three plants viz. Derris elliptica, Linostoma decandrum and Croton tiglium were found to have remarkable larvicidal activity; D. elliptica extract was the most effective and with LC50 value of 0.307 μg/ml its activity was superior to propoxur, the standard synthetic larvicide. Half-life of larvicidal activity of D. elliptica and L. decandrum extracts ranged from 2-4 days.

  2. Adulticidal properties of synthesized silver nanoparticles using leaf extracts of Feronia elephantum (Rutaceae) against filariasis, malaria, and dengue vector mosquitoes.

    Science.gov (United States)

    Veerakumar, Kaliyan; Govindarajan, Marimuthu

    2014-11-01

    Mosquito-borne diseases with an economic impact create loss in commercial and labor outputs, particularly in countries with tropical and subtropical climates. Mosquito control is facing a threat because of the emergence of resistance to synthetic insecticides. Extracts from plants may be alternative sources of mosquito control agents because they constitute a rich source of bioactive compounds that are biodegradable into nontoxic products and potentially suitable for use to control mosquitoes. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. In view of the recently increased interest in developing plant origin insecticides as an alternative to chemical insecticide, in the present study, the adulticidal activity of silver nanoparticles (AgNPs) synthesized using Feronia elephantum plant leaf extract against adults of Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus was determined. The range of concentrations of synthesized AgNPs (8, 16, 24, 32, and 40 μg mL(-1)) and aqueous leaf extract (40, 80, 120, 160, and 200 μg mL(-1)) were tested against the adults of A. stephensi, A. aegypti, and C. quinquefasciatus. Adults were exposed to varying concentrations of aqueous crude extract and synthesized AgNPs for 24 h. Considerable mortality was evident after the treatment of F. elephantum for all three important vector mosquitoes. The synthesized AgNPs from F. elephantum were highly toxic than crude leaf aqueous extract to three important vector mosquito species. The results were recorded from UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy analysis (EDX), and transmission electron microscopy (TEM). Synthesized AgNPs against the vector mosquitoes A. stephensi, A. aegypti, and C. quinquefasciatus had the following lethal dose (LD)₅₀ and LD₉₀ values: A. stephensi had LD₅₀ and LD₉₀ values of 18

  3. Estudo da influência da flora intestinal do mosquito Anopheles sp. no estabelecimento da infecção por Plasmodium Berghei

    OpenAIRE

    Gomes, Joana da Graça

    2013-01-01

    A malária é uma doença infecciosa com um efeito devastador nas áreas afectadas. É provocada pelo protozoário Plasmodium e transmitida pelo insecto vector do género Anopheles. As fêmeas hematófagas ao alimentar-se de um hospedeiro infectado vão dar continuidade ao ciclo de vida do parasita e transmiti-lo a um novo hospedeiro na próxima refeição sanguínea. O intestino médio dos mosquitos é um órgão imunocompetente, onde a presença de microrganismos vai activar o sistema imunitário, determinando...

  4. Inducible immune factors of the vector mosquito Anopheles gambiae: biochemical purification of a defensin antibacterial peptide and molecular cloning of preprodefensin cDNA.

    Science.gov (United States)

    Richman, A M; Bulet, P; Hetru, C; Barillas-Mury, C; Hoffmann, J A; Kafalos, F C

    1996-08-01

    Larvae of the mosquito vector of human malaria, Anopheles gambiae, were inoculated with bacteria and extracts were biochemically fractionated by reverse-phase HPLC. Multiple induced polypeptides and antibacterial activities were observed following bacterial infection, including a member of the insect defensin family of antibacterial proteins. A cDNA encoding An. gambiae preprodefensin was isolated using PCR primers based on phylogenetically conserved sequences. The mature peptide is highly conserved, but the signal and propeptide segments are not, relative to corresponding defensin sequences of other insects. Defensin expression is induced in response to bacterial infection, in both adult and larval stages. In contrast, pupae express defensin mRNA constitutively. Defensin expression may prove a valuable molecular marker to monitor the An. gambiae host response to infection by parasitic protozoa of medical importance. PMID:8799739

  5. Dynamics of immature stages of Anopheles arabiensis and other mosquito species (Diptera: Culicidae) in relation to rice cropping in a rice agro-ecosystem in Kenya.

    Science.gov (United States)

    Mwangangi, Joseph; Shililu, Josephat; Muturi, Ephantus; Gu, Weidong; Mbogo, Charles; Kabiru, Ephantus; Jacob, Benjamin; Githure, John; Novak, Robert

    2006-12-01

    We determined changes in species composition and densities of immature stages of Anopheles arabiensis mosquitoes in relation to rice growth cycle in order to generate data for developing larval control strategies in rice ecosystems. Experimental rice paddies (6.3m x 3.15m) exposed to natural colonization of mosquitoes were sampled weekly for two rice growing cycles between February 2004 and March 2005. Overall, 21,325 Anopheles larvae were collected, of which 91.9% were 1st and 2nd instars and 8.1% were 3rd and 4th instars. An. arabiensis was the predominant species (84.1%) with other species, An. pharoensis (13.5%), An. funestus (2.1%), An. coustani (0.3%), and An. maculipalpis (0.1%) accounting for only a small proportion of the anophelines collected. Culex quinquefasciatus (65.7%) was the predominant species among the non-anopheline species. Others species collected included: C. annulioris (9.9%), C. poicilipes (7.3%), C. tigripes (7.2%), C. duttoni (0.6%), Aedes aegypti (5.3%), Ae. cumminsii (3.5%), and Ae. vittatus (0.7%). The densities of the major anopheline species were closely related to rice stage and condition of the rice field. An. arabiensis, the predominant species, was most abundant over a three-week period after transplanting. Low densities of larvae were collected during the late vegetative, reproductive, and ripening phases of rice. An increase in larval density ten days post-transplanting was found to correlate with the application of fertilizer (sulphate of ammonia). Culicine and aedine species densities were significantly higher during the post-harvesting period. Our results suggest that the transplanting stage is favorable for the growth of immature stages of An. arabiensis and provides a narrow window for targeted larval intervention in rice. PMID:17249341

  6. Biology & control of Anopheles culicifacies Giles 1901.

    Science.gov (United States)

    Sharma, V P; Dev, V

    2015-05-01

    Malaria epidemiology is complex due to multiplicity of disease vectors, sibling species complex and variations in bionomical characteristics, vast varied terrain, various ecological determinants. There are six major mosquito vector taxa in India, viz. Anopheles culicifacies, An. fluviatilis, An. stephensi, An. minimus, An. dirus and An. sundaicus. Among these, An. culicifacies is widely distributed and considered the most important vector throughout the plains and forests of India for generating bulk of malaria cases (>60% annually). Major malaria epidemics are caused by An. culicifaices. It is also the vector of tribal malaria except parts of Odisha and Northeastern States of India. An. culicifacies has been the cause of perennial malaria transmission in forests, and over the years penetrated the deforested areas of Northeast. An. culicifacies participates in malaria transmission either alone or along with An. stephensi or An. fluviatilis. The National Vector Borne Disease Control Programme (NVBDCP) spends about 80 per cent malaria control budget annually in the control of An. culicifacies, yet it remains one of the most formidable challenges in India. With recent advances in molecular biology there has been a significant added knowledge in understanding the biology, ecology, genetics and response to interventions, requiring stratification for cost-effective and sustainable malaria control. Research leading to newer interventions that are evidence-based, community oriented and sustainable would be useful in tackling the emerging challenges in malaria control. Current priority areas of research should include in-depth vector biology and control in problem pockets, preparation of malaria-risk maps for focused and selective interventions, monitoring insecticide resistance, cross-border initiative and data sharing, and coordinated control efforts for achieving transmission reduction, and control of drug-resistant malaria. The present review on An. culicifacies

  7. Comparative susceptibility to permethrin of two Anopheles gambiae s.l. populations from Southern Benin, regarding mosquito sex, physiological status, and mosquito age

    Directory of Open Access Journals (Sweden)

    Nazaire Aïzoun

    2014-04-01

    Conclusions: The resistance is a hereditary and dynamic phenomenon which can be due to metabolic mechanisms like overproduction of detoxifying enzymes activity. Many factors influence vector susceptibility to insecticide. Among these factors, there are mosquito sex, mosquito age, its physiological status. Therefore, it is useful to respect the World Health Organization criteria in the assessment of insecticide susceptibility tests in malaria vectors. Otherwise, susceptibility testing is conducted using unfed female mosquitoes aged 3-5 days old. Tests should also be carried out at (25±2 °C and (80±10% relative humidity.

  8. Attractiveness of volatiles from different body parts to the malaria mosquito Anopheles coluzzii is affected by deodorant compounds

    NARCIS (Netherlands)

    Verhulst, Niels O.; Weldegergis, Berhane T.; Menger, David; Takken, Willem

    2016-01-01

    Mosquitoes display biting preferences among different sites of the human body. In addition to height or convection currents, body odour may play a role in the selection of these biting sites. Previous studies have shown that skin emanations are important host-finding cues for mosquitoes. In this

  9. Electrophysiological responses of gustatory receptor neurons on the labella of the common malaria mosquito Anopheles quadrimaculatus Say (Diptera: Culicidae)

    Science.gov (United States)

    We recorded electrical responses from sensory cells associated with gustatory sensilla on the labella of female Anopheles quadrimaculatus to salt, sucrose, quinine (a feeding deterrent) and the insect repellent, N,N-diethyl-3-methylbenzamide (DEET). A salt-sensitive cell responded to increasing con...

  10. Modified mosquito landing boxes dispensing transfluthrin provide effective protection against Anopheles arabiensis mosquitoes under simulated outdoor conditions in a semi-field system.

    OpenAIRE

    Andrés, Marta; Lorenz, Lena M; Mbeleya, Edgar; Moore, Sarah J.

    2015-01-01

    Abstract Background Efforts to control malaria vectors have primarily focused on scaling-up of long-lasting insecticidal nets (LLINs) and indoor residual spraying. Although highly efficient against indoor-biting and indoor-resting vectors, these interventions have lower impact on outdoor-biting mosquitoes. Innovative vector control tools are required to prevent outdoor human–mosquito contacts. In this work, the potential of spatial repellents, delivered in an active system that requires minim...

  11. Larval food quantity affects the capacity of adult mosquitoes to transmit human malaria

    Science.gov (United States)

    Shapiro, Lillian L. M.; Murdock, Courtney C.; Jacobs, Gregory R.; Thomas, Rachel J.; Thomas, Matthew B.

    2016-01-01

    Adult traits of holometabolous insects are shaped by conditions experienced during larval development, which might impact interactions between adult insect hosts and parasites. However, the ecology of larval insects that vector disease remains poorly understood. Here, we used Anopheles stephensi mosquitoes and the human malaria parasite Plasmodium falciparum, to investigate whether larval conditions affect the capacity of adult mosquitoes to transmit malaria. We reared larvae in two groups; one group received a standard laboratory rearing diet, whereas the other received a reduced diet. Emerging adult females were then provided an infectious blood meal. We assessed mosquito longevity, parasite development rate and prevalence of infectious mosquitoes over time. Reduced larval food led to increased adult mortality and caused a delay in parasite development and a slowing in the rate at which parasites invaded the mosquito salivary glands, extending the time it took for mosquitoes to become infectious. Together, these effects increased transmission potential of mosquitoes in the high food regime by 260–330%. Such effects have not, to our knowledge, been shown previously for human malaria and highlight the importance of improving knowledge of larval ecology to better understand vector-borne disease transmission dynamics. PMID:27412284

  12. One-pot fabrication of silver nanocrystals using Nicandra physalodes: A novel route for mosquito vector control with moderate toxicity on non-target water bugs.

    Science.gov (United States)

    Govindarajan, Marimuthu; Khater, Hanem F; Panneerselvam, Chellasamy; Benelli, Giovanni

    2016-08-01

    Mosquitoes (Diptera: Culicidae) as vectors for important diseases and parasites causing millions of deaths every year. The use of synthetic pesticides against Culicidae leads to resistance and environmental concerns. Therefore, eco-friendly control tools are a priority. In this research, Nicandra physalodes-mediated synthesis of silver nanoparticles (Ag NPs) was conducted, in order to control larval populations of three important mosquito vectors, Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus. Biofabricated Ag NPs were characterized using UV-vis spectrophotometry, XRD, FTIR spectroscopy, SEM, and TEM analyses. Ag NPs were highly toxic against the three mosquito vectors. Maximum efficacy was detected against A. stephensi (LC50=12.39μg/mL), followed by Ae. aegypti (LC50=13.61μg/mL) and Cx. quinquefasciatus (LC50=14.79μg/mL). Interestingly, Ag NPs were safer for the non-target aquatic organism Diplonychus indicus sharing the same aquatic habitats of mosquito larvae. LC50 and LC90 values were 1032.81 and 19,076.59μg/mL, respectively. Overall, our results highlight that N. physalodes-fabricated Ag NPs are a promising for development of eco-friendly larvicides against mosquito vectors, with negligible toxicity against non-target aquatic water bugs.

  13. One-pot fabrication of silver nanocrystals using Nicandra physalodes: A novel route for mosquito vector control with moderate toxicity on non-target water bugs.

    Science.gov (United States)

    Govindarajan, Marimuthu; Khater, Hanem F; Panneerselvam, Chellasamy; Benelli, Giovanni

    2016-08-01

    Mosquitoes (Diptera: Culicidae) as vectors for important diseases and parasites causing millions of deaths every year. The use of synthetic pesticides against Culicidae leads to resistance and environmental concerns. Therefore, eco-friendly control tools are a priority. In this research, Nicandra physalodes-mediated synthesis of silver nanoparticles (Ag NPs) was conducted, in order to control larval populations of three important mosquito vectors, Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus. Biofabricated Ag NPs were characterized using UV-vis spectrophotometry, XRD, FTIR spectroscopy, SEM, and TEM analyses. Ag NPs were highly toxic against the three mosquito vectors. Maximum efficacy was detected against A. stephensi (LC50=12.39μg/mL), followed by Ae. aegypti (LC50=13.61μg/mL) and Cx. quinquefasciatus (LC50=14.79μg/mL). Interestingly, Ag NPs were safer for the non-target aquatic organism Diplonychus indicus sharing the same aquatic habitats of mosquito larvae. LC50 and LC90 values were 1032.81 and 19,076.59μg/mL, respectively. Overall, our results highlight that N. physalodes-fabricated Ag NPs are a promising for development of eco-friendly larvicides against mosquito vectors, with negligible toxicity against non-target aquatic water bugs. PMID:27473981

  14. Mosquito larvicidal and ovicidal properties of Pemphis acidula Frost. (Lythraceae) against Culex tritaeniorhynchus Giles and Anopheles subpictus Grassi (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    K. Samidurai

    2012-01-01

    Objective: This study was undertaken to assess the larvicidal and ovicidal potential of the crude methanol, benzene and acetone solvent extracts from the medicinal plant Pemphis acidula (Pe. acidula) against the medically important mosquito vectors, Culex tritaeniorhynchus (Cx. tritaeniorhynchus) and Anopheles subpictus (An. subpictus) were exposed to various concentrations and (Diptera: Culicidae). Methods: Twenty five late third instar of Cx. tritaeniorhynchus and An. subpictus were exposed to various concentrations and were assayed in the laboratory by using the protocol of WHO 2005. The larval mortality was observed 24 h of treatment. Hundred eggs of Cx. tritaeniorhynchus and An. subpictus were exposed to various concentrations and were assayed in the laboratory by using the protocol of Su and Mulla 1998. The ovicidal activity was observed 48 h of treatment. Results: The LC50 and LC90 values being 10.81and 20.64 and 22.10 and 43.71 ppm and hundred percent of egg mortality was observed at 350 and 400 ppm methanol extract of Pe. acidula against Cx. tritaeniorhynchus and An. subpictus, respectively. Conclusion: These results suggest that the leaf extracts have the potential to be used as an ideal ecofriendly approach for the control of mosquitoes.

  15. Synthesis, Polymorphism, and Insecticidal Activity of Methyl 4-(4-chlorophenyl)-8-iodo-2-methyl-6-oxo-1,6-dihydro-4H-pyrimido[2,1-b]quinazoline-3-Carboxylate Against Anopheles arabiensis Mosquito.

    Science.gov (United States)

    Venugopala, Katharigatta N; Nayak, Susanta K; Gleiser, Raquel M; Sanchez-Borzone, Mariela E; Garcia, Daniel A; Odhav, Bharti

    2016-07-01

    Mosquitoes are the major vectors of pathogens and parasites including those causing malaria, the most deadly vector-borne disease. The negative environmental effects of most synthetic compounds combined with widespread development of insecticide resistance encourage an interest in finding and developing alternative products against mosquitoes. In this study, pyrimido[2,1-b]quinazoline derivative DHPM3 has been synthesized by three-step chemical reaction and screened for larvicide, adulticide, and repellent properties against Anopheles arabiensis, one of the dominant vectors of malaria in Africa. The title compound emerged as potential larvicide agent for further research and development, because it exerted 100% mortality, while adulticide activity was considered moderate.

  16. Di-rhamnolipid is a mosquito pupicidal metabolite from Pseudomonas fluorescens (VCRC B426).

    Science.gov (United States)

    Prabakaran, G; Hoti, S L; Rao, H Surya Prakash; Vijjapu, Satish

    2015-08-01

    Pseudomonas fluorescens Migula (VCRC B426) produces a secondary metabolite, which was found to be active against pupae of vector mosquitoes namely Culex quinquefasciatus, Anopheles stephensi and Aedes aegypti. The mosquito pupicidal metabolite from P. fluoescens was mass produced and separated by ethyl acetate extraction and purified further by silica gel column chromatography, FPLC, HPLC and TLC. The purified metabolite was characterized by NMR, FT-IR, LC-MS and MALDI-TOF. The FT-IR, (1)H and (13)C NMR results showed that it is a rhamnolipid (di-rhamnolipid). The matrix assisted laser desorption and ionization-time-of-flight spectrum of the sample showed predominant pupicidal component produced by P. fluorescens was the molecule mass of 673.40 Da. Owing to its high toxicity to mosquito pupae, especially Anopheles sp., and Aedes sp., the di-rhamnolipd has potential in the control of the vectors of dengue, chikungunya, yellow fever and malaria. This is the first report of mosquito pupicidal di-rhamnolipid from P. fluorescens. PMID:25912083

  17. Repellent, irritant and toxic effects of 20 plant extracts on adults of the malaria vector Anopheles gambiae mosquito

    OpenAIRE

    Emilie Deletre; Thibaud Martin; Pascal Campagne; Denis Bourguet; Andy Cadin; Chantal Menut; Romain Bonafos; Fabrice Chandre

    2013-01-01

    Pyrethroid insecticides induce an excito-repellent effect that reduces contact between humans and mosquitoes. Insecticide use is expected to lower the risk of pathogen transmission, particularly when impregnated on long-lasting treated bednets. When applied at low doses, pyrethroids have a toxic effect, however the development of pyrethroid resistance in several mosquito species may jeopardize these beneficial effects. The need to find additional compounds, either to kill disease-carrying mos...

  18. Mathematical evaluation of community level impact of combining bed nets and indoor residual spraying upon malaria transmission in areas where the main vectors are Anopheles arabiensis mosquitoes

    Directory of Open Access Journals (Sweden)

    Okumu Fredros O

    2013-01-01

    Full Text Available Abstract Background Indoor residual insecticide spraying (IRS and long-lasting insecticide treated nets (LLINs are commonly used together even though evidence that such combinations confer greater protection against malaria than either method alone is inconsistent. Methods A deterministic model of mosquito life cycle processes was adapted to allow parameterization with results from experimental hut trials of various combinations of untreated nets or LLINs (Olyset®, PermaNet 2.0®, Icon Life® nets with IRS (pirimiphos methyl, lambda cyhalothrin, DDT, in a setting where vector populations are dominated by Anopheles arabiensis, so that community level impact upon malaria transmission at high coverage could be predicted. Results Intact untreated nets alone provide equivalent personal protection to all three LLINs. Relative to IRS plus untreated nets, community level protection is slightly higher when Olyset® or PermaNet 2.0® nets are added onto IRS with pirimiphos methyl or lambda cyhalothrin but not DDT, and when Icon Life® nets supplement any of the IRS insecticides. Adding IRS onto any net modestly enhances communal protection when pirimiphos methyl is sprayed, while spraying lambda cyhalothrin enhances protection for untreated nets but not LLINs. Addition of DDT reduces communal protection when added to LLINs. Conclusions Where transmission is mediated primarily by An. arabiensis, adding IRS to high LLIN coverage provides only modest incremental benefit (e.g. when an organophosphate like pirimiphos methyl is used, but can be redundant (e.g. when a pyrethroid like lambda cyhalothin is used or even regressive (e.g. when DDT is used for the IRS. Relative to IRS plus untreated nets, supplementing IRS with LLINs will only modestly improve community protection. Beyond the physical protection that intact nets provide, additional protection against transmission by An. arabiensis conferred by insecticides will be remarkably small, regardless of

  19. Mosquito appetite for blood is stimulated by Plasmodium chabaudi infections in themselves and their vertebrate hosts

    Directory of Open Access Journals (Sweden)

    Ferguson Heather M

    2004-05-01

    Full Text Available Abstract Background Arthropod vectors of disease may encounter more than one infected host during the course of their lifetime. The consequences of super-infection to parasite development are rarely investigated, but may have substantial epidemiological and evolutionary consequences. Methods Using a rodent malaria model system, behavioural avoidance of super-infection was tested by examining whether already-infected Anopheles stephensi mosquitoes were less responsive to new vertebrate hosts if they were infected. Additionally, a second dose of parasites was given to malaria-infected mosquitoes on a biologically realistic time scale to test whether it impeded the development of a first infection. Results No effect of a second infected blood meal on either the prevalence or parasite burden arising from a first was found. Furthermore, it was found that not only were infected mosquitoes more likely to take a second blood meal than their uninfected counterparts, they were disproportionately drawn to infected hosts. Conclusions The alterations in mosquito feeding propensity reported here would occur if parasites have been selected to make infected vertebrate hosts more attractive to mosquitoes, and infected mosquitoes are more likely to seek out new blood meals. Although such a strategy might increase the risk of super-infection, this study suggests the cost to parasite development is not high and as such would be unlikely to outweigh the potential benefits of increasing the contact rate between the parasite's two obligate hosts.

  20. Determination of nitric oxide metabolites, nitrate and nitrite, in Anopheles culicifacies mosquito midgut and haemolymph by anion exchange high-performance liquid chromatography: plausible mechanism of refractoriness

    Directory of Open Access Journals (Sweden)

    Adak Tridibesh

    2008-04-01

    Full Text Available Abstract Background The diverse physiological and pathological role of nitric oxide in innate immune defenses against many intra and extracellular pathogens, have led to the development of various methods for determining nitric oxide (NO synthesis. NO metabolites, nitrite (NO2- and nitrate (NO3- are produced by the action of an inducible Anopheles culicifacies NO synthase (AcNOS in mosquito mid-guts and may be central to anti-parasitic arsenal of these mosquitoes. Method While exploring a plausible mechanism of refractoriness based on nitric oxide synthase physiology among the sibling species of An. culicifacies, a sensitive, specific and cost effective high performance liquid chromatography (HPLC method was developed, which is not influenced by the presence of biogenic amines, for the determination of NO2- and NO3- from mosquito mid-guts and haemolymph. Results This method is based on extraction, efficiency, assay reproducibility and contaminant minimization. It entails de-proteinization by centrifugal ultra filtration through ultracel 3 K filter and analysis by high performance anion exchange liquid chromatography (Sphereclone, 5 μ SAX column with UV detection at 214 nm. The lower detection limit of the assay procedure is 50 pmoles in all midgut and haemolymph samples. Retention times for NO2- and NO3- in standards and in mid-gut samples were 3.42 and 4.53 min. respectively. Assay linearity for standards ranged between 50 nM and 1 mM. Recoveries of NO2- and NO3- from spiked samples (1–100 μM and from the extracted standards (1–100 μM were calculated to be 100%. Intra-assay and inter assay variations and relative standard deviations (RSDs for NO2- and NO3- in spiked and un-spiked midgut samples were 5.7% or less. Increased levels NO2- and NO3- in midguts and haemolymph of An. culicifacies sibling species B in comparison to species A reflect towards a mechanism of refractoriness based on AcNOS physiology. Conclusion HPLC is a sensitive

  1. Application of biogenic carbon dioxide produced by yeast with different carbon sources for attraction of mosquitoes towards adult mosquito traps.

    Science.gov (United States)

    Sukumaran, D; Ponmariappan, S; Sharma, Atul K; Jha, Hemendra K; Wasu, Yogesh H; Sharma, Ajay K

    2016-04-01

    Surveillance is a prime requisite for controlling arthropod vectors like mosquitoes that transmit diseases such as malaria, dengue and chikungunya. Carbon dioxide (CO2) is one of the main cues from vertebrate breath that attracts mosquitoes towards the host. Hence, CO2 is used as an attractant during surveillance of mosquitoes either from commercial cylinders or dry ice for mosquito traps. In the present study, the biogenic carbon dioxide production was optimized with different carbon sources such as glucose, simple sugar and jaggery with and without yeast peptone dextrose (YPD) media using commercial baker's yeast. The results showed that yeast produced more biogenic CO2 with simple sugar as compared to other carbon sources. Further substrate concentration was optimized for the continuous production of biogenic CO2 for a minimum of 12 h by using 10 g of baker's yeast with 50 g of simple sugar added to 1.5 l distilled water (without YPD media) in a 2-l plastic bottle. This setup was applied in field condition along with two different mosquito traps namely Mosquito Killing System (MKS) and Biogents Sentinel (BGS) trap. Biogenic CO2 from this setup has increased the trapping efficiency of MKS by 6.48-fold for Culex quinquefasciatus, 2.62-fold for Aedes albopictus and 1.5-fold for Anopheles stephensi. In the case of BGS, the efficiency was found to be increased by 3.54-fold for Ae. albopictus, 4.33-fold for An. stephensi and 1.3-fold for Armigeres subalbatus mosquitoes. On the whole, plastic bottle setup releasing biogenic CO2 from sugar and yeast has increased the efficiency of MKS traps by 6.38-fold and 2.74-fold for BGS traps as compared to traps without biogenic CO2. The present study reveals that, among different carbon sources used, simple sugar as a substance (which is economical and readily available across the world) yielded maximum biogenic CO2 with yeast. This setup can be used as an alternative to CO2 cylinder and dry ice in any adult mosquito traps to

  2. Hemolytic C-type lectin CEL-III from sea cucumber expressed in transgenic mosquitoes impairs malaria parasite development.

    Directory of Open Access Journals (Sweden)

    Shigeto Yoshida

    2007-12-01

    Full Text Available The midgut environment of anopheline mosquitoes plays an important role in the development of the malaria parasite. Using genetic manipulation of anopheline mosquitoes to change the environment in the mosquito midgut may inhibit development of the malaria parasite, thus blocking malaria transmission. Here we generate transgenic Anopheles stephensi mosquitoes that express the C-type lectin CEL-III from the sea cucumber, Cucumaria echinata, in a midgut-specific manner. CEL-III has strong and rapid hemolytic activity toward human and rat erythrocytes in the presence of serum. Importantly, CEL-III binds to ookinetes, leading to strong inhibition of ookinete formation in vitro with an IC(50 of 15 nM. Thus, CEL-III exhibits not only hemolytic activity but also cytotoxicity toward ookinetes. In these transgenic mosquitoes, sporogonic development of Plasmodium berghei is severely impaired. Moderate, but significant inhibition was found against Plasmodium falciparum. To our knowledge, this is the first demonstration of stably engineered anophelines that affect the Plasmodium transmission dynamics of human malaria. Although our laboratory-based research does not have immediate applications to block natural malaria transmission, these findings have significant implications for the generation of refractory mosquitoes to all species of human Plasmodium and elucidation of mosquito-parasite interactions.

  3. Hemolytic C-type lectin CEL-III from sea cucumber expressed in transgenic mosquitoes impairs malaria parasite development.

    Science.gov (United States)

    Yoshida, Shigeto; Shimada, Yohei; Kondoh, Daisuke; Kouzuma, Yoshiaki; Ghosh, Anil K; Jacobs-Lorena, Marcelo; Sinden, Robert E

    2007-12-01

    The midgut environment of anopheline mosquitoes plays an important role in the development of the malaria parasite. Using genetic manipulation of anopheline mosquitoes to change the environment in the mosquito midgut may inhibit development of the malaria parasite, thus blocking malaria transmission. Here we generate transgenic Anopheles stephensi mosquitoes that express the C-type lectin CEL-III from the sea cucumber, Cucumaria echinata, in a midgut-specific manner. CEL-III has strong and rapid hemolytic activity toward human and rat erythrocytes in the presence of serum. Importantly, CEL-III binds to ookinetes, leading to strong inhibition of ookinete formation in vitro with an IC(50) of 15 nM. Thus, CEL-III exhibits not only hemolytic activity but also cytotoxicity toward ookinetes. In these transgenic mosquitoes, sporogonic development of Plasmodium berghei is severely impaired. Moderate, but significant inhibition was found against Plasmodium falciparum. To our knowledge, this is the first demonstration of stably engineered anophelines that affect the Plasmodium transmission dynamics of human malaria. Although our laboratory-based research does not have immediate applications to block natural malaria transmission, these findings have significant implications for the generation of refractory mosquitoes to all species of human Plasmodium and elucidation of mosquito-parasite interactions. PMID:18159942

  4. Electrophysiological, flight orientation and oviposition responses of three species of mosquito vectors to hexadecyl pentanoate: residual oviposition repellent activity.

    Science.gov (United States)

    Seenivasagan, T; Sharma, Kavita R; Ganesan, K; Prakash, Shri

    2010-05-01

    Understanding on the chemical ecology of mosquito behavior is of paramount importance in developing control programs employing attractants and repellents. Several workers focused on topical repellents and oviposition attractants of mosquitoes, however, only limited work has been accomplished on mosquito oviposition repellents. The present systematic investigation provides evidence on the effectiveness of a C21 fatty acid ester- hexadecyl pentanoate, to stimulate antennal olfactory receptors of Aedes aegypti (L.), Ae. albopictus (Skuse), and Anopheles stephensi (Liston) that mediate their long-range olfaction guided flight orientation behavior by repelling the gravid females of these mosquito vectors in the olfactometer. The compound loaded onto an effervescent tablet retained its repellent property in the treated substrates for up to 1 wk at 10 mg/L. In places, where the mosquito breeding habitats are near to human habitations, could be treated with hexadecyl pentanoate to repel the ovipositing gravid females as a component of the integrated approach for mosquito management by disrupting the mosquito life cycle and population growth.

  5. A CRISPR-Cas9 Gene Drive System Targeting Female Reproduction in the Malaria Mosquito vector Anopheles gambiae

    OpenAIRE

    Hammond, Andrew; Galizi, Roberto; Kyrou, Kyros; Simoni, Alekos; Siniscalchi, Carla; Katsanos, Dimitris; Gribble, Matthew; Baker, Dean; Marois, Eric; Russell, Steven; Burt, Austin; Windbichler, Nikolai; Crisanti, Andrea; Nolan, Tony

    2015-01-01

    Gene-drive systems that enable super-Mendelian inheritance of a transgene have the potential to modify insect populations over a timeframe of a few years [AU please provide a real estimate, this seems vague]. We describe CRISPR-Cas9 endonuclease constructs that function as gene-drive systems in Anopheles gambiae, the main vector for malaria [AU:OK?]. We identified three genes (AGAP005958, AGAP011377 and AGAP007280) that confer a recessive female sterility phenotype upon disruption, and insert...

  6. Identification, characterisation, and function of adipokinetic hormones and receptor in the African malaria mosquito, "Anopheles Gambiae" (Diptera)

    OpenAIRE

    Kaufmann, Christian; Betschart, Bruno

    2007-01-01

    En utilisant la bioinformatique et la biologie moléculaire, nous avons pu identifier chez le principal vecteur africain de la malaria, le moustique, Anopheles gambiae deux hormones adipokinétiques (AKHs): l'octapeptide, Anoga-AKH-I (pQLTFTPAWa) et le décapeptide, Anoga-AKH-II, (pQVTFSRDWNAa). La fonction principale des AKHs est d’induire une hyperlipémie (effet d’adipokinétique), ainsi qu’une hypertrehalosémie et une hyperprolinémie. En tant que membres de la famille des AKH, les deux neurope...

  7. Chemical composition, toxicity and non-target effects of Pinus kesiya essential oil: An eco-friendly and novel larvicide against malaria, dengue and lymphatic filariasis mosquito vectors.

    Science.gov (United States)

    Govindarajan, Marimuthu; Rajeswary, Mohan; Benelli, Giovanni

    2016-07-01

    Mosquitoes (Diptera: Culicidae) are vectors of important parasites and pathogens causing death, poverty and social disability worldwide, with special reference to tropical and subtropical countries. The overuse of synthetic insecticides to control mosquito vectors lead to resistance, adverse environmental effects and high operational costs. Therefore, the development of eco-friendly control tools is an important public health challenge. In this study, the mosquito larvicidal activity of Pinus kesiya leaf essential oil (EO) was evaluated against the malaria vector Anopheles stephensi, the dengue vector Aedes aegypti and the lymphatic filariasis vector Culex quinquefasciatus. The chemical composition of the EO was analyzed by gas chromatography-mass spectroscopy. GC-MS revealed that the P. kesiya EO contained 18 compounds. Major constituents were α-pinene, β-pinene, myrcene and germacrene D. In acute toxicity assays, the EO showed significant toxicity against early third-stage larvae of An. stephensi, Ae. aegypti and Cx. quinquefasciatus, with LC50 values of 52, 57, and 62µg/ml, respectively. Notably, the EO was safer towards several aquatic non-target organisms Anisops bouvieri, Diplonychus indicus and Gambusia affinis, with LC50 values ranging from 4135 to 8390µg/ml. Overall, this research adds basic knowledge to develop newer and safer natural larvicides from Pinaceae plants against malaria, dengue and filariasis mosquito vectors.

  8. Chemical composition, toxicity and non-target effects of Pinus kesiya essential oil: An eco-friendly and novel larvicide against malaria, dengue and lymphatic filariasis mosquito vectors.

    Science.gov (United States)

    Govindarajan, Marimuthu; Rajeswary, Mohan; Benelli, Giovanni

    2016-07-01

    Mosquitoes (Diptera: Culicidae) are vectors of important parasites and pathogens causing death, poverty and social disability worldwide, with special reference to tropical and subtropical countries. The overuse of synthetic insecticides to control mosquito vectors lead to resistance, adverse environmental effects and high operational costs. Therefore, the development of eco-friendly control tools is an important public health challenge. In this study, the mosquito larvicidal activity of Pinus kesiya leaf essential oil (EO) was evaluated against the malaria vector Anopheles stephensi, the dengue vector Aedes aegypti and the lymphatic filariasis vector Culex quinquefasciatus. The chemical composition of the EO was analyzed by gas chromatography-mass spectroscopy. GC-MS revealed that the P. kesiya EO contained 18 compounds. Major constituents were α-pinene, β-pinene, myrcene and germacrene D. In acute toxicity assays, the EO showed significant toxicity against early third-stage larvae of An. stephensi, Ae. aegypti and Cx. quinquefasciatus, with LC50 values of 52, 57, and 62µg/ml, respectively. Notably, the EO was safer towards several aquatic non-target organisms Anisops bouvieri, Diplonychus indicus and Gambusia affinis, with LC50 values ranging from 4135 to 8390µg/ml. Overall, this research adds basic knowledge to develop newer and safer natural larvicides from Pinaceae plants against malaria, dengue and filariasis mosquito vectors. PMID:26995063

  9. Anopheles gambiae odorant binding protein crystal complex with the synthetic repellent DEET: implications for structure-based design of novel mosquito repellents.

    Science.gov (United States)

    Tsitsanou, K E; Thireou, T; Drakou, C E; Koussis, K; Keramioti, M V; Leonidas, D D; Eliopoulos, E; Iatrou, K; Zographos, S E

    2012-01-01

    Insect odorant binding proteins (OBPs) are the first components of the olfactory system to encounter and bind attractant and repellent odors emanating from various sources for presentation to olfactory receptors, which trigger relevant signal transduction cascades culminating in specific physiological and behavioral responses. For disease vectors, particularly hematophagous mosquitoes, repellents represent important defenses against parasitic diseases because they effect a reduction in the rate of contact between the vectors and humans. OBPs are targets for structure-based rational approaches for the discovery of new repellent or other olfaction inhibitory compounds with desirable features. Thus, a study was conducted to characterize the high resolution crystal structure of an OBP of Anopheles gambiae, the African malaria mosquito vector, in complex with N,N-diethyl-m-toluamide (DEET), one of the most effective repellents that has been in worldwide use for six decades. We found that DEET binds at the edge of a long hydrophobic tunnel by exploiting numerous non-polar interactions and one hydrogen bond, which is perceived to be critical for DEET's recognition. Based on the experimentally determined affinity of AgamOBP1 for DEET (K (d) of 31.3 μΜ) and our structural data, we modeled the interactions for this protein with 29 promising leads reported in the literature to have significant repellent activities, and carried out fluorescence binding studies with four highly ranked ligands. Our experimental results confirmed the modeling predictions indicating that structure-based modeling could facilitate the design of novel repellents with enhanced binding affinity and selectivity. PMID:21671117

  10. Mosquito larvicidal properties ofFicus benghalensis L. (Family:Moraceae) againstCulex tritaeniorhynchus Giles andAnopheles subpictus Grassi (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    M Govindarajan; R Sivakumar; A Amsath; S Niraimathi

    2011-01-01

    Objective:To determine the larvicidal efficacy of different solvent leaf extract ofFicus benghalensis (F. benghalensis) against Culex tritaeniorhynchus (Cx. tritaeniorhynchus)and Anopheles subpictus (An. subpictus).Methods: Twenty five early third instar larvae ofCx. tritaeniorhynchusandAn. subpictus were exposed to various concentrations and were assayed in the laboratory by using the protocol ofWHO 2005. The larval mortality was observed after24 h of treatment.Results: Among three solvent extracts tested the maximum efficacy was observed in the methanol extract. TheLC50 andLC90 values ofF. benghalensis against early third instar of Cx. tritaeniorhynchus andAn. subpictus were100.88, 159.76 ppm and56.66, 85.84 ppm, respectively. No mortality was observed in controls. Thechi-square values were significant atP<0.05 level. Conclusions: From the results it can be concluded the crude extract ofF. benghalensis was an excellent potential for controllingCx. tritaeniorhynchusandAn. subpictus mosquito larvae.

  11. Efficacy of IGR compound Starycide 480 SC (Triflumuron against mosquito larvae in clear and polluted water

    Directory of Open Access Journals (Sweden)

    C.P. Batra, P.K. Mittal, T. Adak & M.A. Ansari

    2005-09-01

    Full Text Available Background & objectives: An environmental friendly formulation Starycide 480 SC (Triflumuron–OMS-2015 , a new insect growth regulator with chitin synthesis inhibitor type mode of action wasevaluated against mosquito larvae in laboratory and small-scale field trials carried out in and aroundDelhi.Methods: The formulation was tested in laboratory for its bio-efficacy against late III instar mosquitolarvae of different species using WHO bioassay procedure. In the field formulation was sprayed atdoses of 0.3, 0.5 and 1 ppm (g/m3 in the natural breeding habitats of Anopheles and Culex mosquitoes.The impact was assessed by monitoring densities of larvae by dipper and observing the reductionin larval density and inhibition of adult emergence.Results: In the laboratory, formulation was more effective against larvae of Anopheles stephensi andAedes aegypti than Culex quinquefasciatus, but it produced 100% inhibition of adult emergence forall mosquito species at a concentration of 0.02 ppm. In the field trials, formulation did not produce100% reduction in the density of late stage larvae even at 1 ppm (g/m3, the highest dose tested, butit resulted in 100% inhibition of pupal formation of both Anopheles and Culex spp in different typesof habitats for 3–7 weeks even at a lower dose of 0.5 ppm.Interpretation & conclusion : Application of triflumuron in the natural breeding habitats in bothclean and polluted water @ 0.5 ppm (g/m3 resulted in complete inhibition of adult emergence of bothAnopheles and Culex spp for 3–7 weeks. This formulation may be tested in large-scale field trials forfurther use in the vector control programme.

  12. Arm-specific dynamics of chromosome evolution in malaria mosquitoes

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    Xia Ai

    2011-04-01

    Full Text Available Abstract Background The malaria mosquito species of subgenus Cellia have rich inversion polymorphisms that correlate with environmental variables. Polymorphic inversions tend to cluster on the chromosomal arms 2R and 2L but not on X, 3R and 3L in Anopheles gambiae and homologous arms in other species. However, it is unknown whether polymorphic inversions on homologous chromosomal arms of distantly related species from subgenus Cellia nonrandomly share similar sets of genes. It is also unclear if the evolutionary breakage of inversion-poor chromosomal arms is under constraints. Results To gain a better understanding of the arm-specific differences in the rates of genome rearrangements, we compared gene orders and established syntenic relationships among Anopheles gambiae, Anopheles funestus, and Anopheles stephensi. We provided evidence that polymorphic inversions on the 2R arms in these three species nonrandomly captured similar sets of genes. This nonrandom distribution of genes was not only a result of preservation of ancestral gene order but also an outcome of extensive reshuffling of gene orders that created new combinations of homologous genes within independently originated polymorphic inversions. The statistical analysis of distribution of conserved gene orders demonstrated that the autosomal arms differ in their tolerance to generating evolutionary breakpoints. The fastest evolving 2R autosomal arm was enriched with gene blocks conserved between only a pair of species. In contrast, all identified syntenic blocks were preserved on the slowly evolving 3R arm of An. gambiae and on the homologous arms of An. funestus and An. stephensi. Conclusions Our results suggest that natural selection favors specific gene combinations within polymorphic inversions when distant species are exposed to similar environmental pressures. This knowledge could be useful for the discovery of genes responsible for an association of inversion polymorphisms with

  13. Screening for adulticidal activity against Anopheles arabiensis in ten plants used as mosquito repellent in South Africa

    OpenAIRE

    Mavundza, Edison J; Maharaj, Rajendra; Chukwujekwu, Jude C; Finnie, Jeffrey F; Staden, Johannes Van

    2014-01-01

    Background Due to the development of resistance to synthetic insecticides, adverse effects to human health, non-target organisms and the environment, there is an urgent need to develop new insecticides, which are effective, safe, biodegrable and target-specific. This study was undertaken to evaluate the adulticidal activity of 10 plants used traditionally as mosquito repellents in South Africa. Methods The dried plant materials were extracted with dichloromethane (DCM) and ethanol (EtOH). The...

  14. Constituents of the Essential Oil of Suregada Zanzibariensis Leaves are Repellent to the Mosquito, Anopheles Gambiae s.s.

    OpenAIRE

    Innocent, Ester; Cosam C. Joseph; Gikonyo, Nicholas K; Nkunya, Mayunga H.H.; Hassanali, Ahmed

    2010-01-01

    In traditional African communities, repellent volatiles from certain plants generated by direct burning or by thermal expulsion have played an important role in protecting households against vectors of malaria and other diseases. Previous research on volatile constituents of plants has shown that some are good sources of potent mosquito repellents. In this bioprospecting initiative, the essential oil of leaves of the tree, Suregada zanzibariensis Verdc. (Angiospermae: Euphobiaceae) was tested...

  15. Increase in susceptibility to insecticides with aging of wild Anopheles gambiae mosquitoes from Côte d’Ivoire

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    Chouaibou Mouhamadou S

    2012-09-01

    Full Text Available Abstract Background Appropriate monitoring of vector insecticide susceptibility is required to provide the rationale for optimal insecticide selection in vector control programs. Methods In order to assess the influence of mosquito age on susceptibility to various insecticides, field-collected larvae of An. gambiae s.l. from Tiassalé were reared to adults. Females aged 1, 2, 3, 5 and 10 days were exposed to 5 insecticides (deltamethrin, permethrin, DDT, malathion and propoxur using WHO susceptibility test kits. Outcome measures included the LT50 (exposure time required to achieve 50% knockdown, the RR (resistance ratio, i.e. a calculation of how much more resistant the wild population is compared with a standard susceptible strain and the mortality rate following 1 hour exposure, for each insecticide and each mosquito age group. Results There was a positive correlation between the rate of knockdown and mortality for all the age groups and for all insecticides tested. For deltamethrin, the RR50 was highest for 2 day old and lowest for 10 day old individuals. Overall, mortality was lowest for 2 and 3 day old individuals and significantly higher for 10 day old individuals (P 50 was highest for 1 to 3 day old individuals and lowest for 10 day old individuals and mortality was lowest for 1 to 3 day old individuals, intermediate for 5 day old and highest for 10 day old individuals. DDT did not display any knockdown effect and mortality was low for all mosquito age groups (50 was low (1.54 - 2.77 and mortality was high (>93% for all age groups. With propoxur, no knockdown effect was observed for 1, 2 and 3 day old individuals and a very low level of mortality was observed ( Conclusion Results indicate that for An. gambiae s.l. adults derived from wild-collected larvae, there was an influence of age on insecticide susceptibility status, with younger individuals (1 to 3 days old more resistant than older mosquitoes. This

  16. Green synthesis of silver nanoparticles from Cassia roxburghii-a most potent power for mosquito control.

    Science.gov (United States)

    Muthukumaran, Udaiyan; Govindarajan, Marimuthu; Rajeswary, Mohan

    2015-12-01

    Mosquitoes transmit serious human diseases, causing millions of deaths every year. The use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of synthesized natural products for vector control have been a priority in this area. In the present study, silver nanoparticles (AgNPs) synthesized using Cassia roxburghii plant leaf extract against Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus were determined. Larvae were exposed to varying concentrations of synthesized AgNPs (12, 24, 36, 48, and 60 μg/mL) and aqueous leaf extracts (60, 120, 180, 240, and 300 μg/mL) for 24 h. The synthesized AgNPs were characterized by UV-Vis spectrum, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), with energy-dispersive X-ray spectroscopy analysis (EDX), transmission electron microscopy, and X-ray diffraction analysis (XRD). Compare to aqueous extracted synthesized AgNPs showed extensive mortality rate against An. stephensi, Ae. aegypti, and C. quinquefasciatus with the LC50 and LC90 values that were 26.35, 28.67, 31.27 and 48.81, 53.24, and 58.11 μg/mL, respectively. No mortality was observed in the control. This is the first report on mosquito larvicidal activity of plant-synthesized nanoparticles. Thus, the use of C. roxburghii to synthesize silver nanoparticles is a rapid, eco-friendly, and a single-step approach, and the AgNPs formed can be potential mosquito larvicidal agents. Therefore, this study proves that C. roxburghii is a potential bioresource for stable, reproducible nanoparticle synthesis (AgNPs) and also can be used as an efficient mosquito control agent. This is the first report on the larvicidal activity of the plant extract and AgNPs.

  17. Green synthesis of silver nanoparticles from Cassia roxburghii-a most potent power for mosquito control.

    Science.gov (United States)

    Muthukumaran, Udaiyan; Govindarajan, Marimuthu; Rajeswary, Mohan

    2015-12-01

    Mosquitoes transmit serious human diseases, causing millions of deaths every year. The use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of synthesized natural products for vector control have been a priority in this area. In the present study, silver nanoparticles (AgNPs) synthesized using Cassia roxburghii plant leaf extract against Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus were determined. Larvae were exposed to varying concentrations of synthesized AgNPs (12, 24, 36, 48, and 60 μg/mL) and aqueous leaf extracts (60, 120, 180, 240, and 300 μg/mL) for 24 h. The synthesized AgNPs were characterized by UV-Vis spectrum, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), with energy-dispersive X-ray spectroscopy analysis (EDX), transmission electron microscopy, and X-ray diffraction analysis (XRD). Compare to aqueous extracted synthesized AgNPs showed extensive mortality rate against An. stephensi, Ae. aegypti, and C. quinquefasciatus with the LC50 and LC90 values that were 26.35, 28.67, 31.27 and 48.81, 53.24, and 58.11 μg/mL, respectively. No mortality was observed in the control. This is the first report on mosquito larvicidal activity of plant-synthesized nanoparticles. Thus, the use of C. roxburghii to synthesize silver nanoparticles is a rapid, eco-friendly, and a single-step approach, and the AgNPs formed can be potential mosquito larvicidal agents. Therefore, this study proves that C. roxburghii is a potential bioresource for stable, reproducible nanoparticle synthesis (AgNPs) and also can be used as an efficient mosquito control agent. This is the first report on the larvicidal activity of the plant extract and AgNPs. PMID:26276645

  18. Chemical composition and mosquito repellent activity of the essential oil of Plectranthus incanus link

    Directory of Open Access Journals (Sweden)

    Pal Mahesh

    2011-01-01

    Full Text Available The chemical composition of the essential oil obtained from the leaves of Plectranthus incanus Link, with the yield of 0.6% (w/v, was analyzed by GC and GC/MS. A total of 16 constituents, representing 95.2% of the oil, were identified. The major components of the oil were fenchone (6.0%, piperitone oxide (32.4%, piperitenone (3.0% and piperitenone oxide (41.5%. The repellent activity of the volatile oil at different concentrations was measured by the protection period against the bites of Anopheles stephensi and Culex fatigans. The tested oil had stronger repellent activity than citronella oil, which was used as a positive control. LC50 (30 min for P. incanus oil against An. stephensi and C. fatigans were 23.8 and 19.6 μl/L air, respectively, whereas LC50 of citronella oil were 31.7 and 31.0 μl/L air. Thus, P. incanus may be regarded as a potential valuable source of chemicals that have strong mosquito repellent activity, and could be used for the preparation of mosquito repellent formulations.

  19. Feasibility of Using the Mosquito Blood Meal for Rapid and Efficient Human and Animal Virus Surveillance and Discovery.

    Science.gov (United States)

    Yang, Yu; Garver, Lindsey S; Bingham, Karen M; Hang, Jun; Jochim, Ryan C; Davidson, Silas A; Richardson, Jason H; Jarman, Richard G

    2015-12-01

    Mosquito blood meals taken from humans and animals potentially represent a useful source of blood for the detection of blood-borne pathogens. In this feasibility study, Anopheles stephensi mosquitoes were fed with blood meals spiked with dengue virus type 2 (DENV-2) and harvested at serial time points. These mosquitoes are not competent vectors, and the virus is not expected to replicate. Ingested blood was spotted on Whatman FTA cards and stored at room temperature. Mosquito abdomens were removed and stored at -80°C. Control blood meal aliquots were stored in vials or applied onto FTA cards. After 4 weeks of storage, the samples were extracted using beadbeating and QIAamp Viral RNA kit (Qiagen Sciences, Germantown, MD). Recovered viral RNA was analyzed by DENV-2 TaqMan RT-PCR assay and next-generation sequencing (NGS). Overall viral RNA recovery efficiency was 15% from the directly applied dried blood spots and approximately 20% or higher for dried blood spots made by blotting mosquito midgut on FTA cards. Viral RNA in mosquito-ingested blood decreases over time, but remains detectable 24 hours after blood feeding. The viral sequences in FTA-stored specimens can be maintained at room temperature. The strategy has the potential utility in expedited zoonotic virus discovery and blood-borne pathogen surveillance. PMID:26416112

  20. Laboratory evaluation of Indian medicinal plants as repellents against malaria, dengue, and filariasis vector mosquitoes.

    Science.gov (United States)

    Govindarajan, Marimuthu; Sivakumar, Rajamohan

    2015-02-01

    Mosquito-borne diseases have an economic impact, including loss in commercial and labor outputs, particularly in countries with tropical and subtropical climates; however, no part of the world is free from vector-borne diseases. Mosquitoes are the carriers of severe and well-known illnesses such as malaria, arboviral encephalitis, dengue fever, chikungunya fever, West Nile virus, and yellow fever. These diseases produce significant morbidity and mortality in humans and livestock around the world. In view of the recently increased interest in developing plant origin insecticides as an alternative to chemical insecticides, in the present study, the repellent activity of crude hexane, ethyl acetate, benzene, chloroform, and methanol extracts of leaf of Erythrina indica and root of Asparagus racemosus were assayed for their repellency against three important vector mosquitoes, viz., Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus. The crude extract was applied on a membrane used for membrane feeding of unfed mosquitoes in a 1-ft cage. About 50 unfed 3-4-day-old laboratory-reared pathogen-free strains of A. stephensi, A. aegypti, and C. quinquefasciatus were introduced in a 1-ft cage fitted with a membrane with blood for feeding with temperature maintained at 37 °C through circulating water bath maintained at 40-45 °C. Three concentrations (1.0, 2.0, and 5.0 mg/cm(2)) of the crude extracts were evaluated. Repellents in E. indica afforded longer protection time against A. stephensi, A. aegypti, and C. quinquefasciatus than those in A. racemosus at 5.0 mg/cm(2) concentration, and the mean complete protection time ranged from 120 to 210 min with the different extracts tested. In this observation, these two plant crude extracts gave protection against mosquito bites; also, the repellent activity is dependent on the strength of the plant extracts. These results suggest that the leaf extract of E. indica and root extract of A. racemosus have the potential to

  1. Laboratory evaluation of Indian medicinal plants as repellents against malaria, dengue, and filariasis vector mosquitoes.

    Science.gov (United States)

    Govindarajan, Marimuthu; Sivakumar, Rajamohan

    2015-02-01

    Mosquito-borne diseases have an economic impact, including loss in commercial and labor outputs, particularly in countries with tropical and subtropical climates; however, no part of the world is free from vector-borne diseases. Mosquitoes are the carriers of severe and well-known illnesses such as malaria, arboviral encephalitis, dengue fever, chikungunya fever, West Nile virus, and yellow fever. These diseases produce significant morbidity and mortality in humans and livestock around the world. In view of the recently increased interest in developing plant origin insecticides as an alternative to chemical insecticides, in the present study, the repellent activity of crude hexane, ethyl acetate, benzene, chloroform, and methanol extracts of leaf of Erythrina indica and root of Asparagus racemosus were assayed for their repellency against three important vector mosquitoes, viz., Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus. The crude extract was applied on a membrane used for membrane feeding of unfed mosquitoes in a 1-ft cage. About 50 unfed 3-4-day-old laboratory-reared pathogen-free strains of A. stephensi, A. aegypti, and C. quinquefasciatus were introduced in a 1-ft cage fitted with a membrane with blood for feeding with temperature maintained at 37 °C through circulating water bath maintained at 40-45 °C. Three concentrations (1.0, 2.0, and 5.0 mg/cm(2)) of the crude extracts were evaluated. Repellents in E. indica afforded longer protection time against A. stephensi, A. aegypti, and C. quinquefasciatus than those in A. racemosus at 5.0 mg/cm(2) concentration, and the mean complete protection time ranged from 120 to 210 min with the different extracts tested. In this observation, these two plant crude extracts gave protection against mosquito bites; also, the repellent activity is dependent on the strength of the plant extracts. These results suggest that the leaf extract of E. indica and root extract of A. racemosus have the potential to

  2. Mosquito larvicidal and silver nanoparticles synthesis potential of plant latex

    Directory of Open Access Journals (Sweden)

    H.P. Borase

    2014-08-01

    Full Text Available Silver nanoparticles (AgNPs were synthesized from the latex of the medicinally important plants Euphorbia milii, Euphorbia hirta, Ficus racemosa and Jatropha curcas. Synthesized AgNPs were characterized by UV-Vis spectrophotometry, scanning electron microscopy, energy dispersive X-ray analysis, X-ray diffraction, Fourier transformed infrared spectroscopy, particle size, and zeta potential analysis. Potency of latex and latex-synthesized AgNPs was evaluated against the 2nd and 4th instar larvae of Aedes aegypti and Anopheles stephensi. The lowest lethal concentration 50 (LC50 value among the different types of plant latex studied was observed for latex of E. milii (281.28±23.30 and 178.97±37.82 ppm, respectively against 2nd instar larvae of Ae. aegypti and An. stephensi. E. milii latex-synthesised AgNPs showed a high reduction in LC50 compared with its latex; i.e., 8.76±0.46 and 8.67±0.47 ppm, respectively, for 2nd instars of Ae. aegypti and An. stephensi. LC50 values of AgNPs synthesized using the latex of E. hirta, F. racemosa and J. curcas were lower than those of the latex of the respective plants; i.e., 10.77±0.53, 9.81±0.52, 12.06±0.60 and 8.79±0.51, 9.83±0.52, 9.60±0.51 ppm, respectively, for 2nd instars of An. stephensi and Ae. aegypti. Similarly, as compared with the plant latex, lower LC50 values were reported for latex-synthesized AgNPs against 4th instars of Ae. aegypt and An. stephensi. Results showed that all the types of plant latex investigated have the potential to convert silver nitrate into AgNPs showing a spectrum of potent mosquito larvicidal effects, indicating the possibility of further exploration of the bioefficacy of latex and latex-synthesized AgNPs against vectors of public health concerns.

  3. Larvicidal and repellent potential of Zingiber nimmonii (J. Graham) Dalzell (Zingiberaceae) essential oil: an eco-friendly tool against malaria, dengue, and lymphatic filariasis mosquito vectors?

    Science.gov (United States)

    Govindarajan, Marimuthu; Rajeswary, Mohan; Arivoli, Subramanian; Tennyson, Samuel; Benelli, Giovanni

    2016-05-01

    Mosquitoes (Diptera: Culicidae) are important vectors of terms of public health relevance, especially in tropical and sub-tropical regions. The continuous and indiscriminate use of conventional pesticides for the control of mosquito vectors has resulted in the development of resistance and negative impacts on non-target organisms and the environment. Therefore, there is a need for development of effective mosquito control tools. In this study, the larvicidal and repellent activity of Zingiber nimmonii rhizome essential oil (EO) was evaluated against the malaria vector Anopheles stephensi, the dengue vector Aedes aegypti, and the lymphatic filariasis vector Culex quinquefasciatus. The chemical composition of the EO was analyzed by gas chromatography-mass spectroscopy (GC-MS). GC-MS revealed that the Z. nimmonii EO contained at least 33 compounds. Major constituents were myrcene, β-caryophyllene, α-humulene, and α-cadinol. In acute toxicity assays, the EO showed significant toxicity against early third-stage larvae of An. stephensi, Ae. aegypti, and Cx. quinquefasciatus, with LC50 values of 41.19, 44.46, and 48.26 μg/ml, respectively. Repellency bioassays at 1.0, 2.0, and 5.0 mg/cm(2) of Z. nimmonii EO gave 100 % protection up to 120, 150, and 180 min. against An. stephensi, followed by Ae. aegypti (90, 120, and 150 min) and Cx. quinquefasciatus (60, 90, and 120 min). Furthermore, the EO was safer towards two non-target aquatic organisms, Diplonychus indicus and Gambusia affinis, with LC50 values of 3241.53 and 9250.12 μg/ml, respectively. Overall, this research adds basic knowledge to develop newer and safer natural larvicides and repellent from Zingiberaceae plants against malaria, dengue, and filariasis mosquito vectors. PMID:26792432

  4. Overexpression and altered nucleocytoplasmic distribution of Anopheles ovalbumin-like SRPN10 serpins in Plasmodium-infected midgut cells.

    Science.gov (United States)

    Danielli, Alberto; Barillas-Mury, Carolina; Kumar, Sanjeev; Kafatos, Fotis C; Loukeris, Thanasis G

    2005-02-01

    The design of effective, vector-based malaria transmission blocking strategies relies on a thorough understanding of the molecular and cellular interactions that occur during the parasite sporogonic cycle in the mosquito. During Plasmodium berghei invasion, transcription from the SRPN10 locus, encoding four serine protease inhibitors of the ovalbumin family, is strongly induced in the mosquito midgut. Herein we demonstrate that intense induction as well as redistribution of SRPN10 occurs specifically in the parasite-invaded midgut epithelial cells. Quantitative analysis establishes that in response to epithelial invasion, SRPN10 translocates from the nucleus to the cytoplasm and this is followed by strong SRPN10 overexpression. The invaded cells exhibit signs of apoptosis, suggesting a link between this type of intracellular serpin and epithelial damage. The SRPN10 gene products constitute a novel, robust and cell-autonomous marker of midgut invasion by ookinetes. The SRPN10 dynamics at the subcellular level confirm and further elaborate the 'time bomb' model of P. berghei invasion in both Anopheles stephensi and Anopheles gambiae. In contrast, this syndrome of responses is not elicited by mutant P. berghei ookinetes lacking the major ookinete surface proteins, P28 and P25. Molecular markers with defined expression patterns, in combination with mutant parasite strains, will facilitate dissection of the molecular mechanisms underlying vector competence and development of effective transmission blocking strategies. PMID:15659062

  5. Tissue-specific differences in the spatial interposition of X-chromosome and 3R chromosome regions in the malaria mosquito Anopheles messeae Fall.

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    Gleb Artemov

    Full Text Available Spatial organization of a chromosome in a nucleus is very important in biology but many aspects of it are still generally unresolved. We focused on tissue-specific features of chromosome architecture in closely related malaria mosquitoes, which have essential inter-specific differences in polytene chromosome attachments in nurse cells. We showed that the region responsible for X-chromosome attachment interacts with nuclear lamina stronger in nurse cells, then in salivary glands cells in Anopheles messeae Fall. The inter-tissue differences were demonstrated more convincingly in an experiment of two distinct chromosomes interposition in the nucleus space of cells from four tissues. Microdissected DNA-probes from nurse cells X-chromosome (2BC and 3R chromosomes (32D attachment regions were hybridized with intact nuclei of nurse cells, salivary gland cells, follicle epithelium cells and imaginal disсs cells in 3D-FISH experiments. We showed that only salivary gland cells and follicle epithelium cells have no statistical differences in the interposition of 2BC and 32D. Generally, the X-chromosome and 3R chromosome are located closer to each other in cells of the somatic system in comparison with nurse cells on average. The imaginal disсs cell nuclei have an intermediate arrangement of chromosome interposition, similar to other somatic cells and nurse cells. In spite of species-specific chromosome attachments there are no differences in interposition of nurse cells chromosomes in An. messeae and An. atroparvus Thiel. Nurse cells have an unusual chromosome arrangement without a chromocenter, which could be due to the special mission of generative system cells in ontogenesis and evolution.

  6. Repeated landmass reformation limits diversification in the widespread littoral zone mosquito Anopheles sundaicus sensu lato in the Indo-Oriental Region.

    Science.gov (United States)

    Zarowiecki, Magdalena; Linton, Yvonne-Marie; Post, Rory J; Bangs, Michael J; Htun, Pe Than; Hlaing, Thaung; Seng, Chang Moh; Baimai, Visut; Ding, Trung Ho; Sochantha, Tho; Walton, Catherine

    2014-05-01

    Southeast Asia harbours abundant biodiversity, hypothesized to have been generated by Pliocene and Pleistocene climatic and environmental change. Vicariance between the island of Borneo, the remaining Indonesian archipelago and mainland Southeast Asia caused by elevated sea levels during interglacial periods has been proposed to lead to diversification in the littoral zone mosquito Anopheles (Cellia) sundaicus (Rodenwaldt) sensu lato. To test this biogeographical hypothesis, we inferred the population history and assessed gene flow of A. sundaicus s.l. sampled from 18 populations across its pan-Asian species range, using sequences from mitochondrial cytochrome c oxidase subunit 1 (CO1), the internal transcribed spacer 2 (ITS2) and the mannose phosphate isomerase (Mpi) gene. A hypothesis of ecological speciation for A. sundaicus involving divergent adaptation to brackish and freshwater larval habitats was also previously proposed, based on a deficiency of heterozygotes for Mpi allozyme alleles in sympatry. This hypothesis was not supported by Mpi sequence data, which exhibited no fixed differences between brackish and freshwater larval habitats. Mpi and CO1 supported the presence of up to eight genetically distinct population groupings. Counter to the hypothesis of three allopatric species, divergence was often no greater between Borneo, Sumatra/Java and the Southeast Asian mainland than it was between genetic groupings within these landmasses. An isolation-with-migration (IM) model indicates recurrent gene flow between the current major landmasses. Such gene flow would have been possible during glacial periods when the current landmasses merged, presenting opportunities for dispersal along expanding and contracting coastlines. Consequently, Pleistocene climatic variation has proved a homogenizing, rather than diversifying, force for A. sundaicus diversity. PMID:24750501

  7. Prolonged Colonisation, Irradiation, and Transportation do not Impede Mating Vigour and Competitiveness of Male Anopheles arabiensis Mosquitoes under Semifield Conditions in Northern Sudan

    International Nuclear Information System (INIS)

    Background. In Sudan, the Sterile Insect Technique (SIT) is being developed to suppress populations of Anopheles arabiensis. The present study was carried out to evaluate the impact of long-term colonisation, irradiation, and transportation on male vigour and mating competitiveness under controlled semi-field conditions. Materials and Methods. Male mosquitoes were irradiated in Khartoum as pupae and transported 400 km to the field site in Dongola. Wild males and females were collected as immature stages (larvae and pupae) from the field site and sexed immediately after adult emergence. Competition experiments were carried out to test the mating competitiveness and vigour of colonised males (non-irradiated or irradiated) against wild conspecifics in the semi-field system. Results. Mortality resulting from packaging and transportation from Khartoum to Dongola was low for adults (1.1% for irradiated and 1.3% for non-irradiated males). In contrast, all irradiated pupae died on their way to the field site. On average, 54.9% females were inseminated after one night. There were no differences between the number of females inseminated by colony males and those inseminated by wild males. Only a slightly significant difference between the numbers of females inseminated by irradiated males (14.0±1.7) or by wild males (19.7±1.7) was observed. However, the competitive index (CI) for irradiated and colony males when competed with wild males were 0.71 and 0.81 respectively. Conclusions. Packing and transportation methods for pupae need to be improved. Prolonged colonisation (68 generations), irradiation and transportation of adult males did not affect their ability to locate virgin females and compete against wild conspecifics. Irradiation, in contrast to many reports, only had a marginal effect on released males during the first night after their release. These findings support the feasibility of staging an SIT campaign against this malaria vector. (author)

  8. Chemical composition and larvicidal activity of essential oil from Mentha spicata (Linn.) against three mosquito species.

    Science.gov (United States)

    Govindarajan, M; Sivakumar, R; Rajeswari, M; Yogalakshmi, K

    2012-05-01

    Mosquitoes are blood-feeding insects and serve as the most important vectors for spreading human diseases such as malaria, yellow fever, dengue fever, and filariasis. The continued use of synthetic insecticides has resulted in resistance in mosquitoes. Synthetic insecticides are toxic and affect the environment by contaminating soil, water, and air, and then natural products may be an alternative to synthetic insecticides because they are effective, biodegradable, eco-friendly, and safe to environment. Botanical origin may serve as suitable alternative biocontrol techniques in the future. Mentha spicata, an edible and medicinal plant, is chiefly distributed in Southeast Asia and South Asia. In the present study, the toxicity of mosquito larvicidal activity of leaf essential oil (EO) and their major chemical constituents from Mentha spicata against Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi. The chemical composition of the leaf EO was analyzed using gas chromatography-mass spectroscopy (GC-MS). GC-MS revealed that the EO of M. spicata contained 18 compounds. The major chemical components identified were carvone (48.60%), cis-carveol (21.30%), and limonene (11.30%). The EO had a significant toxic effect against early third-stage larvae of C. quinquefasciatus, A. aegypti, and A. stephensi with LC(50) values of 62.62, 56.08, and 49.71 ppm and LC(90) values of 118.70, 110.28, and 100.99 ppm, respectively. The three major pure constituents extracted from the M. spicata leaf EO were also tested individually against three mosquito larvae. The LC(50) values of carvone, cis-carveol, and limonene appeared to be most effective against A. stephensi (LC(50) 19.33, 28.50, and 8.83 ppm) followed by A. aegypti (LC(50) 23.69, 32.88, and 12.01 ppm), and C. quinquefasciatus (LC(50) 25.47, 35.20, and 14.07 ppm). The results could be useful in search for newer, safer, and more effective natural larvicidal agents against C. quinquefasciatus, A. aegypti, and A

  9. Chemical composition and larvicidal activity of essential oil from Mentha spicata (Linn.) against three mosquito species.

    Science.gov (United States)

    Govindarajan, M; Sivakumar, R; Rajeswari, M; Yogalakshmi, K

    2012-05-01

    Mosquitoes are blood-feeding insects and serve as the most important vectors for spreading human diseases such as malaria, yellow fever, dengue fever, and filariasis. The continued use of synthetic insecticides has resulted in resistance in mosquitoes. Synthetic insecticides are toxic and affect the environment by contaminating soil, water, and air, and then natural products may be an alternative to synthetic insecticides because they are effective, biodegradable, eco-friendly, and safe to environment. Botanical origin may serve as suitable alternative biocontrol techniques in the future. Mentha spicata, an edible and medicinal plant, is chiefly distributed in Southeast Asia and South Asia. In the present study, the toxicity of mosquito larvicidal activity of leaf essential oil (EO) and their major chemical constituents from Mentha spicata against Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi. The chemical composition of the leaf EO was analyzed using gas chromatography-mass spectroscopy (GC-MS). GC-MS revealed that the EO of M. spicata contained 18 compounds. The major chemical components identified were carvone (48.60%), cis-carveol (21.30%), and limonene (11.30%). The EO had a significant toxic effect against early third-stage larvae of C. quinquefasciatus, A. aegypti, and A. stephensi with LC(50) values of 62.62, 56.08, and 49.71 ppm and LC(90) values of 118.70, 110.28, and 100.99 ppm, respectively. The three major pure constituents extracted from the M. spicata leaf EO were also tested individually against three mosquito larvae. The LC(50) values of carvone, cis-carveol, and limonene appeared to be most effective against A. stephensi (LC(50) 19.33, 28.50, and 8.83 ppm) followed by A. aegypti (LC(50) 23.69, 32.88, and 12.01 ppm), and C. quinquefasciatus (LC(50) 25.47, 35.20, and 14.07 ppm). The results could be useful in search for newer, safer, and more effective natural larvicidal agents against C. quinquefasciatus, A. aegypti, and A

  10. Possibility of false-positive detection for sporozoites in mosquitos (Diptera: Culicidae) by nested polymerase chain reaction using Plasmodium yoelii genomic DNA.

    Science.gov (United States)

    Tsuzuki, A; Toma, T; Miyagi, I; Toma, H; Arakawa, T; Sato, Y; Kobayashi, J; Mugissa, M F

    2001-06-01

    Anopheles stephensi Liston and An. saperoi Bohart and Ingram infected with the rodent malaria parasite Plasmodium yoelii nigeriense. They were examined 12 and 19 days after blood feeding for sporozoites in head with anterior thorax (HT) and oocysts in abdomen with posterior thorax (AB) by light microscopy and by the nested polymerase chain reaction (nested PCR-based on the amplification of the sequences of the small subunit ribosomal RNA gene). The detection rate of parasite DNA by nested PCR in HT samples 12 days after blood feeding was similar to that by microscopic method. However, in HT samples 19 days after blood feeding, the rate by the PCR method was higher than that by the microscopic method. The incidence of sporozoites in salivary glands of infected mosquitos for 12 days after blood sucking was examined by the PCR method. Parasite DNA in HT of Aedes albopictus Skuse (a non vector for the rodent malaria) as well as An. stephensi and An. saperoi was detected for up to 4 days after feeding on mouse with the rodent malaria parasites. The results indicate that when the PCR method is used for detection of sporozoites of human malaria in mosquitos collected in the field, there are possibilities of including false-positive data for mosquitos that have just or recently fed on human blood infected with malaria (erythrocytic form).

  11. Laboratory studies on the olfactory behaviour of Anopheles quadriannulatus

    NARCIS (Netherlands)

    Pates, H.V.; Takken, W.; Curtis, C.F.

    2005-01-01

    The host preference of Anopheles quadriannulatus Theobald (Diptera: Culicidae), the zoophilic member of the malaria mosquito complex Anopheles gambiae Giles, was investigated in a dual-choice olfactometer. Naïve female mosquitoes were exposed to CO2, acetone, 1-octen-3-ol, and skin emanations from c

  12. Synthesis, Polymorphism, and Insecticidal Activity of Methyl 4-(4-chlorophenyl)-8-iodo-2-methyl-6-oxo-1,6-dihydro-4H-pyrimido[2,1-b]quinazoline-3-Carboxylate Against Anopheles arabiensis Mosquito.

    Science.gov (United States)

    Venugopala, Katharigatta N; Nayak, Susanta K; Gleiser, Raquel M; Sanchez-Borzone, Mariela E; Garcia, Daniel A; Odhav, Bharti

    2016-07-01

    Mosquitoes are the major vectors of pathogens and parasites including those causing malaria, the most deadly vector-borne disease. The negative environmental effects of most synthetic compounds combined with widespread development of insecticide resistance encourage an interest in finding and developing alternative products against mosquitoes. In this study, pyrimido[2,1-b]quinazoline derivative DHPM3 has been synthesized by three-step chemical reaction and screened for larvicide, adulticide, and repellent properties against Anopheles arabiensis, one of the dominant vectors of malaria in Africa. The title compound emerged as potential larvicide agent for further research and development, because it exerted 100% mortality, while adulticide activity was considered moderate. PMID:26841246

  13. Effect of food on immature development, consumption rate, and relative growth rate of Toxorhynchites splendens (Diptera: Culicidae, a predator of container breeding mosquitoes

    Directory of Open Access Journals (Sweden)

    D Dominic Amalraj

    2005-12-01

    Full Text Available Food utilization by the larvae of Toxorhynchites splendens (Wiedemann was studied in the laboratory by offering larvae of Aedes aegypti Linnaeus, Anopheles stephensi (Liston, and Culex quinquefasciatus (Say. Quantitative analyses of data indicated that immature development was significantly faster with increase in food availability. The regression analysis showed that the degrees of the relationship between immature duration (Id and food availability were higher when offered early instars of prey (first and second instars than late instars. Consumption rate (Cr of the predator increased with increase in food availability and this relationship was highly significant when larvae of An. stephensi were offered as food. Consumption rate to food level decreased with increase in the age class of the prey. There was a significant negative correlation between Id and Cr. This aspect helps to increase population turnover of T. splendens in a shorter period when the prey is abundant. Conversely, the predator compensated the loss in daily food intake at low food level by extending Id thereby attains the minimum threshold pupal weight for adult emergence. There was an increase in the relative growth rate (RGR of the predator when An. stephensi was offered as prey and this was related to the high protein content of the prey per body weight. There was a positive correlation between Cr and RGR. This adaptive life characteristic strategy of this predator is useful for mass-rearing for large scale field release programmes in the control of container breeding mosquitoes is discussed.

  14. Plant-borne ovicides in the fight against mosquito vectors of medical and veterinary importance: a systematic review.

    Science.gov (United States)

    Benelli, Giovanni

    2015-09-01

    Mosquitoes (Diptera: Culicidae) are a huge threat for millions of people worldwide, since they act as vectors for devastating parasites and pathogens. Culicidae control is of crucial importance. Mosquito eggs, larvae, and pupae are usually targeted using organophosphates, insect growth regulators, and microbial agents. Indoor residual spraying and insecticide-treated bed nets are also employed. However, these chemicals have negative effects on human health and the environment, and induce resistance in a number of species. Eco-friendly tools have been recently implemented against mosquito vectors, including botanical insecticides. The majority of researches focused on larvicides (745 SCOPUS results, July 2015) and adult repellents (434 SCOPUS results), while limited efforts were conducted to identify effective ovicides of botanical origin (59 SCOPUS results). Here, I review current knowledge on the effectiveness of plant-borne ovicides against major mosquito vectors of medical and veterinary importance. The majority of researches focused on the toxicity of crude extracts, their fractions, or essential oils against three important mosquito vectors, Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus. As a general trend, C. quinquefasciatus eggs were the most resistant to botanical ovicides. Five studies proposed selected compounds from plant extracts and essential oils as ovicides effective at few parts per million. However, no efforts were conducted to shed light on possible mechanisms underlying the toxicity of plant-borne ovicides. In the final section, a number of hot issues needing further research and cooperation among parasitologists, entomologists, and researchers working in natural product chemistry are outlined.

  15. Experimental hut evaluation of bednets treated with an organophosphate (chlorpyrifos-methyl or a pyrethroid (lambdacyhalothrin alone and in combination against insecticide-resistant Anopheles gambiae and Culex quinquefasciatus mosquitoes

    Directory of Open Access Journals (Sweden)

    Corbel Vincent

    2005-05-01

    Full Text Available Abstract Background Pyrethroid resistant mosquitoes are becoming increasingly common in parts of Africa. It is important to identify alternative insecticides which, if necessary, could be used to replace or supplement the pyrethroids for use on treated nets. Certain compounds of an earlier generation of insecticides, the organophosphates may have potential as net treatments. Methods Comparative studies of chlorpyrifos-methyl (CM, an organophosphate with low mammalian toxicity, and lambdacyhalothrin (L, a pyrethroid, were conducted in experimental huts in Côte d'Ivoire, West Africa. Anopheles gambiae and Culex quinquefasciatus mosquitoes from the area are resistant to pyrethroids and organophosphates (kdr and insensitive acetylcholinesterase Ace.1R. Several treatments and application rates on intact or holed nets were evaluated, including single treatments, mixtures, and differential wall/ceiling treatments. Results and Conclusion All of the treatments were effective in reducing blood feeding from sleepers under the nets and in killing both species of mosquito, despite the presence of the kdr and Ace.1R genes at high frequency. In most cases, the effects of the various treatments did not differ significantly. Five washes of the nets in soap solution did not reduce the impact of the insecticides on A. gambiae mortality, but did lead to an increase in blood feeding. The three combinations performed no differently from the single insecticide treatments, but the low dose mixture performed encouragingly well indicating that such combinations might be used for controlling insecticide resistant mosquitoes. Mortality of mosquitoes that carried both Ace.1R and Ace.1S genes did not differ significantly from mosquitoes that carried only Ace.1S genes on any of the treated nets, indicating that the Ace.1R allele does not confer effective resistance to chlorpyrifos-methyl under the realistic conditions of an experimental hut.

  16. Physiological correlates of ecological divergence along an urbanization gradient: differential tolerance to ammonia among molecular forms of the malaria mosquito Anopheles gambiae

    Directory of Open Access Journals (Sweden)

    Tene Fossog Billy

    2013-01-01

    Full Text Available Abstract Background Limitations in the ability of organisms to tolerate environmental stressors affect their fundamental ecological niche and constrain their distribution to specific habitats. Evolution of tolerance, therefore, can engender ecological niche dynamics. Forest populations of the afro-tropical malaria mosquito Anopheles gambiae have been shown to adapt to historically unsuitable larval habitats polluted with decaying organic matter that are found in densely populated urban agglomerates of Cameroon. This process has resulted in niche expansion from rural to urban environments that is associated with cryptic speciation and ecological divergence of two evolutionarily significant units within this taxon, the molecular forms M and S, among which reproductive isolation is significant but still incomplete. Habitat segregation between the two forms results in a mosaic distribution of clinally parapatric patches, with the M form predominating in the centre of urban agglomerates and the S form in the surrounding rural localities. We hypothesized that development of tolerance to nitrogenous pollutants derived from the decomposition of organic matter, among which ammonia is the most toxic to aquatic organisms, may affect this pattern of distribution and process of niche expansion by the M form. Results Acute toxicity bioassays indicated that populations of the two molecular forms occurring at the extremes of an urbanization gradient in Yaounde, the capital of Cameroon, differed in their response to ammonia. The regression lines best describing the dose-mortality profile differed in the scale of the explanatory variable (ammonia concentration log-transformed for the S form and linear for the M form, and in slope (steeper for the S form and shallower for the M form. These features reflected differences in the frequency distribution of individual tolerance thresholds in the two populations as assessed by probit analysis, with the M form exhibiting

  17. Exploration of larvicidal and adult emergence inhibition activities of Ricinus communis seed extract against three potential mosquito vectors in Kolkata, India

    Institute of Scientific and Technical Information of China (English)

    Shyamapada Mandal

    2010-01-01

    Objective:To determine the larvicidal and adult emergence inhibition activities of castor (Ricinus communis) seed extract against three potential mosquito vectorsAnopheles stephensi (An. stephensi), Culex quinquefasciatus (Cx. quinquefasciatus) andAedes albopictus (Ae. albopictus) in India.Methods: TheR. communis seed extract was tested, employingWHO procedure, against fourth larval instars of the three mosquito species for 24 h and larval mortalities were recorded at various concentrations (2-64 μg/mL); the 24 hLC50 values of theR. communis seed extract were determined following Probit analysis. The larval killing, antipupation and adult emergence inhibition rates of the test extract, using a single concentration of2μLC50, were studied at different time periods (24-72 h); the extract toxicity was tested against a fish,Oreochromis niloticus (O. niloticus).Results: TheR. communis seed extract exhibited larvicidal effects with 100 % killing activities at concentrations32-64 μg/mL, and withLC50values 7.10, 11.64 and 16.84μg/mL forCx. quinquefasciatus, An. stephensiand Ae. albopictuslarvae, respectively. When the larvae were treated with the extract at a single concentration of2×LC50, significant differences were observed, compared to control groups, in rate of pupation (P<0.001) as well as in adult formation (P<0.001).Conclusions: The present findings suggest that theR. communis seed extract provided an excellent potential for controllingAn. stephensi, Cx. quinquefasciatus andAe. albopictus mosquito vectors.

  18. Evaluation of plant-mediated synthesized silver nanoparticles against vector mosquitoes.

    Science.gov (United States)

    Veerakumar, Kaliyan; Govindarajan, Marimuthu; Hoti, S L

    2014-12-01

    Diseases transmitted by blood-feeding mosquitoes, such as dengue fever, dengue hemorrhagic fever, Japanese encephalitis, malaria, and filariasis, are increasing in prevalence, particularly in tropical and subtropical zones. To control mosquitoes and mosquito-borne diseases, which have worldwide health and economic impacts, synthetic insecticide-based interventions are still necessary, particularly in situations of epidemic outbreak and sudden increases of adult mosquitoes. Green nanoparticle synthesis has been achieved using environmentally acceptable plant extract and eco-friendly reducing and capping agents. In view of the recently increased interest in developing plant origin insecticides as an alternative to chemical insecticide, in the present study, the adulticidal activity of silver nanoparticles (AgNPs) synthesized using Heliotropium indicum plant leaf extract against adults of Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus was determined. Adult mosquitoes were exposed to varying concentrations of aqueous extract of H. indicum and synthesized AgNPs for 24 h. AgNPs were rapidly synthesized using the leaf extract of H. indicum, and the formation of nanoparticles was observed within 6 h. The results recorded from UV-vis spectrum, Fourier transform infrared, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy support the biosynthesis and characterization of AgNPs. The maximum efficacy was observed in synthesized AgNPs against the adult of A. stephensi (lethal dose (LD)₅₀ = 26.712 μg/mL; LD₉₀ = 49.061 μg/mL), A. aegypti (LD₅₀ = 29.626 μg/mL; LD₉₀ = 54.269 μg/mL), and C. quinquefasciatus (LD₅₀ = 32.077 μg/mL; LD₉₀ = 58.426 μg/mL), respectively. No mortality was observed in the control. These results suggest that the leaf aqueous extracts of H.indicum and green synthesis of AgNPs have the potential to be used as an ideal eco-friendly approach for the control of

  19. Evaluation of plant-mediated synthesized silver nanoparticles against vector mosquitoes.

    Science.gov (United States)

    Veerakumar, Kaliyan; Govindarajan, Marimuthu; Hoti, S L

    2014-12-01

    Diseases transmitted by blood-feeding mosquitoes, such as dengue fever, dengue hemorrhagic fever, Japanese encephalitis, malaria, and filariasis, are increasing in prevalence, particularly in tropical and subtropical zones. To control mosquitoes and mosquito-borne diseases, which have worldwide health and economic impacts, synthetic insecticide-based interventions are still necessary, particularly in situations of epidemic outbreak and sudden increases of adult mosquitoes. Green nanoparticle synthesis has been achieved using environmentally acceptable plant extract and eco-friendly reducing and capping agents. In view of the recently increased interest in developing plant origin insecticides as an alternative to chemical insecticide, in the present study, the adulticidal activity of silver nanoparticles (AgNPs) synthesized using Heliotropium indicum plant leaf extract against adults of Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus was determined. Adult mosquitoes were exposed to varying concentrations of aqueous extract of H. indicum and synthesized AgNPs for 24 h. AgNPs were rapidly synthesized using the leaf extract of H. indicum, and the formation of nanoparticles was observed within 6 h. The results recorded from UV-vis spectrum, Fourier transform infrared, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy support the biosynthesis and characterization of AgNPs. The maximum efficacy was observed in synthesized AgNPs against the adult of A. stephensi (lethal dose (LD)₅₀ = 26.712 μg/mL; LD₉₀ = 49.061 μg/mL), A. aegypti (LD₅₀ = 29.626 μg/mL; LD₉₀ = 54.269 μg/mL), and C. quinquefasciatus (LD₅₀ = 32.077 μg/mL; LD₉₀ = 58.426 μg/mL), respectively. No mortality was observed in the control. These results suggest that the leaf aqueous extracts of H.indicum and green synthesis of AgNPs have the potential to be used as an ideal eco-friendly approach for the control of

  20. Monoclonal antibodies AC-43 and AC-29 disrupt Plasmodium vivax development in the Indian malaria vector Anopheles culicifacies (Diptera: culicidae)

    Indian Academy of Sciences (India)

    Manoj Chugh; B R Gulati; S K Gakhar

    2010-03-01

    A repertoire of monoclonal antibodies (mAbs) was generated against the midgut proteins of Anopheles culicifacies mosquitoes. The mAbs AC-43 and AC-29 significantly inhibited Plasmodium vivax development inside the mosquito midgut. The number of oocysts that developed was reduced by 78.6% when mosquitoes ingested a combination of these two mAbs along with the blood meal. AC-43 mAb binds to the epitope common in 97, 80 and 43 kDa polypeptides from the midgut protein extract, as indicated by western blot analysis. Similarly, the mAb AC-29 recognized 52, 44, 40 and 29 kDa polypeptides. These female midgut-specific polypeptides are shared between An. culicifacies and An. stephensi, two major vectors of malaria in India. Deglycosylation assays revealed that -linked carbohydrates are the major components in epitopes corresponding to AC-43 and AC-29. Gold particle labelling revealed that both these mAbs preferentially bind to glycoproteins at the apical microvilli and the microvillus-associated network present inside transverse sections of the gut epithelium. These regions are particularly known to have receptors for ookinetes, which enable them to cross this epithelial barrier and provide them with certain necessary chemicals or components for further development into oocysts. Therefore, these glycoproteins appear to be potential candidates for a vectordirected transmission-blocking vaccine (TBV).

  1. S argassum muticum-synthesized silver nanoparticles: an effective control tool against mosquito vectors and bacterial pathogens.

    Science.gov (United States)

    Madhiyazhagan, Pari; Murugan, Kadarkarai; Kumar, Arjunan Naresh; Nataraj, Thiyagarajan; Dinesh, Devakumar; Panneerselvam, Chellasamy; Subramaniam, Jayapal; Mahesh Kumar, Palanisamy; Suresh, Udaiyan; Roni, Mathath; Nicoletti, Marcello; Alarfaj, Abdullah A; Higuchi, Akon; Munusamy, Murugan A; Benelli, Giovanni

    2015-11-01

    Mosquito-borne diseases represent a deadly threat for millions of people worldwide. Furthermore, pathogens and parasites polluting water also constitute a severe plague for populations of developing countries. In this research, silver nanoparticles (AgNP) were synthesized using the aqueous extract of the seaweed Sargassum muticum. The production of AgNP was confirmed by surface plasmon resonance band illustrated in UV-vis spectrophotometry. AgNP were characterized by FTIR, SEM, EDX, and XRD analyses. AgNP were mostly spherical in shape, crystalline in nature, with face-centered cubic geometry, and mean size was 43-79 nm. Toxicity of AgNP was assessed against Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus. In laboratory, AgNP were highly toxic against larvae and pupae of the three mosquito species. Maximum efficacy was observed against A. stephensi larvae, with LC50 ranging from 16.156 ppm (larva I) to 28.881 ppm (pupa). In the field, a single treatment with AgNP (10 × LC50) in water storage reservoirs was effective against the three mosquito vectors, allowing complete elimination of larval populations after 72 h. In ovicidal experiments, egg hatchability was reduced by 100% after treatment with 30 ppm of AgNP. Ovideterrence assays highlighted that 10 ppm of AgNP reduced oviposition rates of more than 70% in A. aegypti, A. stephensi, and C. quinquefasciatus (OAI = -0.61, -0.63, and -0.58, respectively). Antibacterial properties of AgNP were evaluated against Bacillus subtilis, Klebsiella pneumoniae, and Salmonella typhi using the agar disk diffusion and minimum inhibitory concentration protocol. AgNP tested at 50 ppm evoked growth inhibition zones larger than 5 mm in all tested bacteria. Overall, the chance to use S. muticum-synthesized AgNP for control of mosquito vectors seems promising since they are effective at low doses and may constitute an advantageous alternative to build newer and safer mosquito control tools. This is the first

  2. Evaluation of organophosphorus and synthetic pyrethroid insecticides against six vector mosquitoe species Avaliação de inseticidas organofosforados e piretroides sintéticos contra seis mosquitos vetores

    Directory of Open Access Journals (Sweden)

    Domingo Montada Dorta

    1993-12-01

    Full Text Available Three organophosphorus compounds- malathion, folithion and temephos- and two synthetic pyrethroids- alphamethrin and deltamethrin- were used for monitoring the susceptibility status of larvae and adults of six vector mosquitoe species: Culex quinquefasciatus (Filariasis and Aedes albopictus (Dengue (both laboratory and field strains; laboratory strains of Aedes aegypti (Dengue, Anopheles slephensi and Anopheles culicifacies (Malaria, and Culex tritaeniorhynchus (Japanese encephalitis in India. From the LC50 values obtained for these insecticides, it was found that all mosquito species including the field strains of Cx. quinquefasciatus and Ae. albopictus were highly susceptible Except for Cx. quinquefasciatus (field strain against malathion, 100% mortality was observed at the discriminating dosages recommended by World Health Organization. The residual effect of alphamethrin, deltamethrin, malathion and folithion at 25 mg (ai/m² on different surfaces against six species of vector mosquitoes showed that alphamethrin was the most effective on all four treated surfaces (mud, plywood, cement and thatch. Nevertheless, residual efficacy lasted longer on thatch than on the other surfaces. Therefore, synthetic pyrethroids such as alphamethrin can be effectively employed in integrated vector control operations.Três compostos organo-fosforados - malation, folition e temefos -e dois piretroides sintéticos - alfametrina e deltametrina - foram usados para controlar o estado da susceptibilidade das larvas e adultos de seis mosquitos vetores na Índia. Foram utilizadas cepas de laboratório e área de Culex quinquefasciatus (filariasis e Aedes albopictus (Dengue e cepas de laboratório de Aedes aegypti (Dengue, Anopheles stephensi e Anopheles culicifacies (Malária e Culex tritaenorhynchus (encefalite japonesa. Os valores de C1(50 obtidos para esses inseticidas mostram que todas as espécies incluindo as cepas de área foram muito susceptíveis. Nos

  3. Synthesis and characterization of silver nanoparticles using Gmelina asiatica leaf extract against filariasis, dengue, and malaria vector mosquitoes.

    Science.gov (United States)

    Muthukumaran, Udaiyan; Govindarajan, Marimuthu; Rajeswary, Mohan; Hoti, S L

    2015-05-01

    Mosquitoes are blood-feeding insects and serve as the most important vectors for spreading human diseases such as malaria, yellow fever, dengue fever, and filariasis. The continued use of synthetic insecticides has resulted in resistance in mosquitoes. Synthetic insecticides are toxic and affect the environment by contaminating soil, water, and air, and then natural products may be an alternative to synthetic insecticides because they are effective, biodegradable, eco-friendly, and safe to environment. Botanical origin may serve as suitable alternative biocontrol techniques in the future. The present study was carried out to establish the larvicidal potential of leaf extracts of Gmelina asiatica and synthesized silver nanoparticles using aqueous leaf extract against late third instar larvae of Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus. Larvae were exposed to varying concentrations of plant extracts and synthesized AgNPs for 24 h. The results were recorded from UV-visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy analysis support the biosynthesis and characterization of AgNPs. The maximum efficacy was observed in synthesized AgNPs against the larvae of An. stephensi (lethal dose (LC₅₀) = 22.44 μg/mL; LC₉₀ 40.65 μg/mL), Ae. aegypti (LC₅₀ = 25.77 μg/mL; LC₉₀ 45.98 μg/mL), and C. quinquefasciatus (LC₅₀ = 27.83 μg/mL; LC₉₀ 48.92 μg/mL), respectively. No mortality was observed in the control. This is the first report on mosquito larvicidal activity of plant-synthesized nanoparticles. Thus, the use of G. asiatica to synthesize silver nanoparticles is a rapid, eco-friendly, and a single-step approach and the AgNps formed can be potential mosquito larvicidal agents.

  4. Synthesis and characterization of silver nanoparticles using Gmelina asiatica leaf extract against filariasis, dengue, and malaria vector mosquitoes.

    Science.gov (United States)

    Muthukumaran, Udaiyan; Govindarajan, Marimuthu; Rajeswary, Mohan; Hoti, S L

    2015-05-01

    Mosquitoes are blood-feeding insects and serve as the most important vectors for spreading human diseases such as malaria, yellow fever, dengue fever, and filariasis. The continued use of synthetic insecticides has resulted in resistance in mosquitoes. Synthetic insecticides are toxic and affect the environment by contaminating soil, water, and air, and then natural products may be an alternative to synthetic insecticides because they are effective, biodegradable, eco-friendly, and safe to environment. Botanical origin may serve as suitable alternative biocontrol techniques in the future. The present study was carried out to establish the larvicidal potential of leaf extracts of Gmelina asiatica and synthesized silver nanoparticles using aqueous leaf extract against late third instar larvae of Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus. Larvae were exposed to varying concentrations of plant extracts and synthesized AgNPs for 24 h. The results were recorded from UV-visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy analysis support the biosynthesis and characterization of AgNPs. The maximum efficacy was observed in synthesized AgNPs against the larvae of An. stephensi (lethal dose (LC₅₀) = 22.44 μg/mL; LC₉₀ 40.65 μg/mL), Ae. aegypti (LC₅₀ = 25.77 μg/mL; LC₉₀ 45.98 μg/mL), and C. quinquefasciatus (LC₅₀ = 27.83 μg/mL; LC₉₀ 48.92 μg/mL), respectively. No mortality was observed in the control. This is the first report on mosquito larvicidal activity of plant-synthesized nanoparticles. Thus, the use of G. asiatica to synthesize silver nanoparticles is a rapid, eco-friendly, and a single-step approach and the AgNps formed can be potential mosquito larvicidal agents. PMID:25666372

  5. Sustained activation of Akt elicits mitochondrial dysfunction to block Plasmodium falciparum infection in the mosquito host.

    Directory of Open Access Journals (Sweden)

    Shirley Luckhart

    2013-02-01

    Full Text Available The overexpression of activated, myristoylated Akt in the midgut of female transgenic Anopheles stephensi results in resistance to infection with the human malaria parasite Plasmodium falciparum but also decreased lifespan. In the present study, the understanding of mitochondria-dependent midgut homeostasis has been expanded to explain this apparent paradox in an insect of major medical importance. Given that Akt signaling is essential for cell growth and survival, we hypothesized that sustained Akt activation in the mosquito midgut would alter the balance of critical pathways that control mitochondrial dynamics to enhance parasite killing at some cost to survivorship. Toxic reactive oxygen and nitrogen species (RNOS rise to high levels in the midgut after blood feeding, due to a combination of high NO production and a decline in FOXO-dependent antioxidants. Despite an apparent increase in mitochondrial biogenesis in young females (3 d, energy deficiencies were apparent as decreased oxidative phosphorylation and increased [AMP]/[ATP] ratios. In addition, mitochondrial mass was lower and accompanied by the presence of stalled autophagosomes in the posterior midgut, a critical site for blood digestion and stem cell-mediated epithelial maintenance and repair, and by functional degradation of the epithelial barrier. By 18 d, the age at which An. stephensi would transmit P. falciparum to human hosts, mitochondrial dysfunction coupled to Akt-mediated repression of autophagy/mitophagy was more evident and midgut epithelial structure was markedly compromised. Inhibition of RNOS by co-feeding of the nitric-oxide synthase inhibitor L-NAME at infection abrogated Akt-dependent killing of P. falciparum that begins within 18 h of infection in 3-5 d old mosquitoes. Hence, Akt-induced changes in mitochondrial dynamics perturb midgut homeostasis to enhance parasite resistance and decrease mosquito infective lifespan. Further, quality control of mitochondrial

  6. Plectranthus amboinicus leaf extract mediated synthesis of zinc oxide nanoparticles and its control of methicillin resistant Staphylococcus aureus biofilm and blood sucking mosquito larvae

    Science.gov (United States)

    Vijayakumar, S.; Vinoj, G.; Malaikozhundan, B.; Shanthi, S.; Vaseeharan, B.

    2015-02-01

    In this study, zinc oxide nanoparticles were biologically synthesized using the leaf extract of Plectranthus amboinicus (Pam-ZnO NPs). The synthesized Pam-ZnO NPs were characterized by UV-Vis spectrophotometer, FTIR, TEM and XRD analysis. TEM analysis of Pam-ZnO NPs showed the average size of about 20-50 nm. Pam-ZnO NPs control the growth of methicillin-resistant Staphylococcus aureus biofilms (MRSA ATCC 33591) at the concentration of 8-10 μg/ml. Confocal laser scanning microscope (CLSM) images revealed that Pam-ZnO NPs strongly inhibited the biofilm forming ability of S. aureus. In addition, Pam-ZnO NPs showed 100% mortality of fourth instar mosquito larvae of Anopheles stephensi, Culex quinquefasciatus and Culex tritaeniorhynchus at the concentration of 8 and 10 μg/ml. The histopathological studies of Pam-ZnO NPs treated A. stephensi and C. quinquefasciatus larvae revealed the presence of damaged cells and tissues in the mid-gut. The damaged tissues suffered major changes including rupture and disintegration of epithelial layer and cellular vacuolization. The present study conclude that Pam-ZnO NPs showed effective control of S. aureus biofilms and mosquito larvae by damaging the mid gut cells.

  7. An analysis of diet quality, how it controls fatty acid profiles, isotope signatures and stoichiometry in the malaria mosquito Anopheles arabiensis.

    Directory of Open Access Journals (Sweden)

    Rebecca Hood-Nowotny

    Full Text Available BACKGROUND: Knowing the underlying mechanisms of mosquito ecology will ensure effective vector management and contribute to the overall goal of malaria control. Mosquito populations show a high degree of population plasticity in response to environmental variability. However, the principle factors controlling population size and fecundity are for the most part unknown. Larval habitat and diet play a crucial role in subsequent mosquito fitness. Developing the most competitive insects for sterile insect technique programmes requires a "production" orientated perspective, to deduce the most effective larval diet formulation; the information gained from this process offers us some insight into the mechanisms and processes taking place in natural native mosquito habitats. METHODOLOGY/PRINCIPAL FINDINGS: Fatty acid profiles and de-novo or direct assimilation pathways, of whole-individual mosquitoes reared on a range of larval diets were determined using pyrolysis gas chromatograph/mass spectrometry. We used elemental analysis and isotope ratio mass spectrometry to measure individual-whole-body carbon, nitrogen and phosphorous values and to assess the impact of dietary quality on subsequent population stoichiometry, size, quality and isotopic signature. Diet had the greatest impact on fatty acid (FA profiles of the mosquitoes, which exhibited a high degree of dietary routing, characteristic of generalist feeders. De-novo synthesis of a number of important FAs was observed. Mosquito C:N stoichiometry was fixed in the teneral stage. Dietary N content had significant influence on mosquito size, and P was shown to be a flexible pool which limited overall population size. CONCLUSIONS/SIGNIFICANCE: Direct routing of FAs was evident but there was ubiquitous de-novo synthesis suggesting mosquito larvae are competent generalist feeders capable of survival on diet with varying characteristics. It was concluded that nitrogen availability in the larval diet

  8. Effects of a botanical larvicide derived from Azadirachta indica (the neem tree) on oviposition behaviour in Anopheles gambiae s.s. mosquitoes

    NARCIS (Netherlands)

    Howard, A.F.V.; Adongo, E.A.; Vulule, J.; Githure, J.

    2011-01-01

    More focus is given to mosquito larval control due to the necessity to use several control techniques together in integrated vector management programmes. Botanical products are thought to be able to provide effective, sustainable and cheap mosquito larval control tools. However, bio-larvicides like

  9. Incorporating the effects of humidity in a mechanistic model of Anopheles gambiae mosquito population dynamics in the Sahel region of Africa

    OpenAIRE

    Yamana, Teresa K.; Eltahir, Elfatih A B

    2013-01-01

    Background: Low levels of relative humidity are known to decrease the lifespan of mosquitoes. However, most current models of malaria transmission do not account for the effects of relative humidity on mosquito survival. In the Sahel, where relative humidity drops to levels

  10. Studies on mosquitoes (Diptera: Culicidae and anthropic environment: 1- Parity of blood seeking Anopheles (Kerteszia in South-Eastern Brazil Estudos sobre mosquitos (Diptera: Culicidae e ambiente antrópico: 1- Paridade de Anopheles (Kerteszia em atividade hematófaga, na região sudeste do Brasil

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1993-02-01

    Full Text Available Populations of Anopheles (Kerteszia were sampled fortnightly over a one-year period (August 1991 to July 1992 at Ribeira Valley, S. Paulo State, Brazil. Indoor and outdoor collections were made on human bait at evening crepuscular period. The Polovodova technique for age grading was applied to 3,501 females of Anopheles cruzii and to 416 females of An. bellator. That sample represented 34.4% of the total number of mosquitoes collected. The most abundant species found was An. cruzii. However, An. bellator showed an endophagy that was almost three times greater than that of An. cruzii. The overall parous rate was 25.4% and uniparity was practically dominant one. A proportion of 26.9% of An. cruzii and 12.0% of An. bellator were found to be uniparous. Only three outdoor females of the former species (0.1% showed biparity. Parity of An. cruzii was higher in females caught outdoors than in those caught indoors. Nevertheless, 497 nulliparous females examined (417 cruzii and 80 bellator had ovaries that had advanced to Christophers and Mer stages III to V. These results imply that these females had already practised hematophagy. Relating these results to those from the parous females, a high statistical significance was found, leading to the conclusion that gonothophic discordance is a common pattern among these anophelines. Further, these results obtained with human bait catches strongly suggest that nearly 38.0% of these host-seeking females had already taken at least one previous blood-meal. So it is possible that enough time could thus be available for the plasmodian development in the vectors.Relata-se os resultados obtidos em coletas regulares de Anopheles cruzii e An. bellator, mediante o emprego de isca humana e por ocasião do crepúsculo vespertino. Objetivou-se, precipuamente, conhecer a paridade de populações dessas espécies, quando em plena tentativa hematófaga, tanto no ambiente intra como peridomiciliar. As coletas foram levadas a

  11. Identification of candidate volatiles that affect the behavioural response of the malaria mosquito Anopheles gambiae sensu stricto to an active kairomone blend: laboratory and semi-field assays

    NARCIS (Netherlands)

    Smallegange, R.C.; Bukovinszkine Kiss, G.; Otieno, B.; Mbadi, P.A.; Takken, W.; Mukabana, W.R.; Loon, van J.J.A.

    2012-01-01

    Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) is the most important vector of human malaria in sub-Saharan Africa, affecting the lives of millions of people. Existing tools such as insecticide-treated nets and indoor-residual sprays are not only effective, but also have limitations as a

  12. Mating competitiveness of male Anopheles arabiensis mosquitoes irradiated with a partially or fully sterilizing dose in small and large laboratory cages

    NARCIS (Netherlands)

    Helinski, M.; Knols, B.G.J.

    2008-01-01

    Male mating competitiveness is a crucial parameter in many genetic control programs including the sterile insect technique (SIT). We evaluated competitiveness of male Anopheles arabiensis Patton as a function of three experimental variables: (1) small or large cages for mating, (2) the effects of ei

  13. Environmental characteristics of anopheline mosquito larval habitats in a malaria endemic area in Iran

    Institute of Scientific and Technical Information of China (English)

    Moussa Soleimani-Ahmadi; Hassan Vatandoost; Ahmad-Ali Hanafi-Bojd; Mehdi Zare; Reza Safari; Abdolrasul Mojahedi; Fatemeh Poorahmad-Garbandi

    2013-01-01

    Objective: To determine the effects of environmental parameters of larval habitats on distribution and abundance of anopheline mosquitoes in Rudan county of Iran. Methods: This cross-sectional study was conducted during the mosquito breeding season from February 2010 to October 2011. The anopheline larvae were collected using the standard dipping method. The specimens were identified using a morphological-based key. Simultaneously with larval collection, environmental parameters of the larval habitats including water current and turbidity, sunlight situation, and substrate type of habitats were recorded. Water samples were taken from breeding sites during larval collection. Before collection of samples, the water temperature was measured. The water samples were analysed for turbidity, conductivity, total alkalinity, total dissolved solid, pH and ions including chloride, sulphate, calcium, and magnesium. Statistical correlation analysis and ANOVA test were used to analyze the association between environmental parameters and larval mosquito abundance. Results: In total 2 973 larvae of the genus Anopheles were collected from 25 larval habitats and identified using morphological characters. They comprised of six species:An. dthali turkhudi (3.30%), and An. apoci (1.14%). The most abundant species was An. dthali which were collected from all of the study areas. Larvae of two malaria vectors, An. dthali and An. stephensi, co-existed and collected in a wide range of habitats with different physico-chemical parameters. The most common larval habitats were man-made sites such as sand mining pools with clean and still water. The anopheline mosquitoes also preferred permanent habitats in sunlight with sandy substrates. The results indicated that there was a significant relationship between mean physico-chemical parameters such as water temperature, conductivity, total alkalinity, sulphate, chloride, and mosquito distribution and abundance. Conclusions: The results of this

  14. Efficacy of essential oil from Cananga odorata (Lamk.) Hook.f. & Thomson (Annonaceae) against three mosquito species Aedes aegypti (L.), Anopheles dirus (Peyton and Harrison), and Culex quinquefasciatus (Say).

    Science.gov (United States)

    Soonwera, Mayura

    2015-12-01

    The essential oil of Cananga odorata flowers was evaluated for oviposition-deterrent, ovicidal, insecticidal, and repellent activities toward three mosquito species: Aedes aegypti, Anopheles dirus, and Culex quinquefasciatus. Oviposition deterrence of the oil was evaluated on gravid females using oviposition deterrence bioassay. The results showed that 10 % Ca. odorata exhibited high percent effective repellency against oviposition at 99.4 % to Ae. aegypti, 97.1 % to An. dirus, and 100 % to Cx. quinquefasciatus. Ca. odorata oil was tested for ovicidal activity. Regression equations revealed that the ovicidal rates were positively correlated with the concentrations of the essential oil. As the concentration of essential oil increased from 1, 5, and up to 10 % concentration, the ovicidal rate increased accordingly. Larvicidal activity of the oils was used on immature stages (third and fourth instar lavae and pupae). The maximum larval mortality was found with 10 % Ca. odorata against immature stages, and there were LC50 values ranged from 10.4 to 10.5 % (for Ae. aegypti), odorata oil had high knockdown rates against the three mosquito species at 96 % (for Ae. aegypti), 98.4 % (for An. dirus), and 100 % (for Cx. quinquefasciatus), with EC50 values of 6.2, 4.7, and 5.4 %, respectively. It gave moderate mortality rates after 24 and 48 h of exposure. Ca. odorata oil was assessed for repellency to females by using the modified K&D module. Ten percent Ca. odorata oil gave the strongest value against Ae. aegypti, An. dirus, and Cx. quinquefasciatus, with percentage repellency of 66, 92, and 90 %, respectively. This study demonstrates the potential for the essential oil of Ca. odorata essential oil to be used as a botanical insecticide against three mosquito species. PMID:26337270

  15. Efficacy of essential oil from Cananga odorata (Lamk.) Hook.f. & Thomson (Annonaceae) against three mosquito species Aedes aegypti (L.), Anopheles dirus (Peyton and Harrison), and Culex quinquefasciatus (Say).

    Science.gov (United States)

    Soonwera, Mayura

    2015-12-01

    The essential oil of Cananga odorata flowers was evaluated for oviposition-deterrent, ovicidal, insecticidal, and repellent activities toward three mosquito species: Aedes aegypti, Anopheles dirus, and Culex quinquefasciatus. Oviposition deterrence of the oil was evaluated on gravid females using oviposition deterrence bioassay. The results showed that 10 % Ca. odorata exhibited high percent effective repellency against oviposition at 99.4 % to Ae. aegypti, 97.1 % to An. dirus, and 100 % to Cx. quinquefasciatus. Ca. odorata oil was tested for ovicidal activity. Regression equations revealed that the ovicidal rates were positively correlated with the concentrations of the essential oil. As the concentration of essential oil increased from 1, 5, and up to 10 % concentration, the ovicidal rate increased accordingly. Larvicidal activity of the oils was used on immature stages (third and fourth instar lavae and pupae). The maximum larval mortality was found with 10 % Ca. odorata against immature stages, and there were LC50 values ranged from 10.4 to 10.5 % (for Ae. aegypti), <1 % (for An. dirus), and <1 % (for Cx. quinquefasciatus). Adulticidal properties were evaluated with unfed females. Ten percent Ca. odorata oil had high knockdown rates against the three mosquito species at 96 % (for Ae. aegypti), 98.4 % (for An. dirus), and 100 % (for Cx. quinquefasciatus), with EC50 values of 6.2, 4.7, and 5.4 %, respectively. It gave moderate mortality rates after 24 and 48 h of exposure. Ca. odorata oil was assessed for repellency to females by using the modified K&D module. Ten percent Ca. odorata oil gave the strongest value against Ae. aegypti, An. dirus, and Cx. quinquefasciatus, with percentage repellency of 66, 92, and 90 %, respectively. This study demonstrates the potential for the essential oil of Ca. odorata essential oil to be used as a botanical insecticide against three mosquito species.

  16. Larvicidal activity of neem oil (Azadirachta indica formulation against mosquitoes

    Directory of Open Access Journals (Sweden)

    Dua Virendra K

    2009-06-01

    Full Text Available Abstract Background Mosquitoes transmit serious human diseases, causing millions of deaths every year. Use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of botanical origin have been reported as useful for control of mosquitoes. Azadirachta indica (Meliaceae and its derived products have shown a variety of insecticidal properties. The present paper discusses the larvicidal activity of neem-based biopesticide for the control of mosquitoes. Methods Larvicidal efficacy of an emulsified concentrate of neem oil formulation (neem oil with polyoxyethylene ether, sorbitan dioleate and epichlorohydrin developed by BMR & Company, Pune, India, was evaluated against late 3rd and early 4th instar larvae of different genera of mosquitoes. The larvae were exposed to different concentrations (0.5–5.0 ppm of the formulation along with untreated control. Larvicidal activity of the formulation was also evaluated in field against Anopheles, Culex, and Aedes mosquitoes. The formulation was diluted with equal volumes of water and applied @ 140 mg a.i./m2 to different mosquito breeding sites with the help of pre calibrated knapsack sprayer. Larval density was determined at pre and post application of the formulation using a standard dipper. Results Median lethal concentration (LC50 of the formulation against Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti was found to be 1.6, 1.8 and 1.7 ppm respectively. LC50 values of the formulation stored at 26°C, 40°C and 45°C for 48 hours against Ae. aegypti were 1.7, 1.7, 1.8 ppm while LC90 values were 3.7, 3.7 and 3.8 ppm respectively. Further no significant difference in LC50 and LC90 values of the formulation was observed against Ae. aegypti during 18 months storage period at room temperature. An application of the formulation at the rate of 140 mg a.i./m2 in different breeding

  17. Studies on mosquitoes (Diptera: Culicidae and anthropicenvironment: 5- Breeding of Anopheles albitarsis in flooded rice fields in South-Eastern Brazil

    Directory of Open Access Journals (Sweden)

    Forattini Oswaldo Paulo

    1994-01-01

    Full Text Available Studies on breeding Anopheles albitarsis and association with rice growth in irrigated paddy fields were carried out during the rice cultivation cycle from December 1993 to March 1994. This period corresponded to the length of time of permanent paddy flooding. Breeding occurred in the early stage up until five weeks after transplantation when rice plant height was small. That inverse correlation may give potential direction to control measures.

  18. Studies on mosquitoes (Diptera: Culicidae and anthropicenvironment: 5- Breeding of Anopheles albitarsis in flooded rice fields in South-Eastern Brazil

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1994-10-01

    Full Text Available Studies on breeding Anopheles albitarsis and association with rice growth in irrigated paddy fields were carried out during the rice cultivation cycle from December 1993 to March 1994. This period corresponded to the length of time of permanent paddy flooding. Breeding occurred in the early stage up until five weeks after transplantation when rice plant height was small. That inverse correlation may give potential direction to control measures.

  19. Spatial and temporal distribution of the malaria mosquito Anopheles arabiensis in northern Sudan: influence of environmental factors and implications for vector control

    OpenAIRE

    Malcolm Colin A; Benedict Mark Q; Knols Bart GJ; Hassan M'oawia M; Cox Jonathan; Ageep Tellal B; Babiker Ahmed; El Sayed Badria B

    2009-01-01

    Abstract Background Malaria is an important public health problem in northern Sudan, but little is known about the dynamics of its transmission. Given the characteristic low densities of Anopheles arabiensis and the difficult terrain in this area, future vector control strategies are likely to be based on area-wide integrated pest management (AW-IPM) that may include the sterile insect technique (SIT). To support the planning and implementation of future AW-IPM activities, larval surveys were...

  20. Plant-mediated biosynthesis of nanoparticles as an emerging tool against mosquitoes of medical and veterinary importance: a review.

    Science.gov (United States)

    Benelli, Giovanni

    2016-01-01

    Mosquitoes (Diptera: Culicidae) are a key threat for millions of people worldwide, since they act as vectors for devastating parasites and pathogens. Mosquito young instars are usually targeted with organophosphates, insect growth regulators and microbial control agents. Indoors residual spraying and insecticide-treated bed nets are also employed. However, these chemicals have strong negative effects on human health and the environment. Newer and safer tools have been recently implemented to enhance control of mosquitoes. In this review, I focus on characterization, effectiveness, and non-target effects of mosquitocidal nanoparticles synthesized using botanical products (mosquitocidal nanoparticles, MNP). The majority of plant-fabricated MNP are silver ones. The synthesis of MNP is usually confirmed by UV-visualization spectroscopy, followed by scanning electron microscopy or transmission electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction studies. Interestingly, plant-synthesized metal nanoparticles have been reported as effective ovicides, larvicides, pupicides, adulticides, and oviposition deterrents against different mosquito species of medical and veterinary importance. Few parts per million of different MNP are highly toxic against the malaria vector Anopheles stephensi, the dengue vector Aedes aegypti, and the filariasis mosquito Culex quiquefasciatus. However, despite the growing number of evidences about the effectiveness of MNP, moderate efforts have been carried out to shed light on their possible non-target effects against mosquito's natural enemies and other aquatic organisms. In the final section, particular attention was dedicated to this issue. A number of hot areas that need further research and cooperation among parasitologists and entomologists are highlighted.

  1. Plant-mediated biosynthesis of nanoparticles as an emerging tool against mosquitoes of medical and veterinary importance: a review.

    Science.gov (United States)

    Benelli, Giovanni

    2016-01-01

    Mosquitoes (Diptera: Culicidae) are a key threat for millions of people worldwide, since they act as vectors for devastating parasites and pathogens. Mosquito young instars are usually targeted with organophosphates, insect growth regulators and microbial control agents. Indoors residual spraying and insecticide-treated bed nets are also employed. However, these chemicals have strong negative effects on human health and the environment. Newer and safer tools have been recently implemented to enhance control of mosquitoes. In this review, I focus on characterization, effectiveness, and non-target effects of mosquitocidal nanoparticles synthesized using botanical products (mosquitocidal nanoparticles, MNP). The majority of plant-fabricated MNP are silver ones. The synthesis of MNP is usually confirmed by UV-visualization spectroscopy, followed by scanning electron microscopy or transmission electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction studies. Interestingly, plant-synthesized metal nanoparticles have been reported as effective ovicides, larvicides, pupicides, adulticides, and oviposition deterrents against different mosquito species of medical and veterinary importance. Few parts per million of different MNP are highly toxic against the malaria vector Anopheles stephensi, the dengue vector Aedes aegypti, and the filariasis mosquito Culex quiquefasciatus. However, despite the growing number of evidences about the effectiveness of MNP, moderate efforts have been carried out to shed light on their possible non-target effects against mosquito's natural enemies and other aquatic organisms. In the final section, particular attention was dedicated to this issue. A number of hot areas that need further research and cooperation among parasitologists and entomologists are highlighted. PMID:26541154

  2. Feeding stage, species, body part and sex-specific activity of glutathione S-transferase in mosquito.

    Science.gov (United States)

    Tripathy, A; Kar, S K

    2015-03-01

    In the present study, the feeding stage, body parts, development and sex specific activity of Glutathione S-transferases (GSTs) were observed in different mosquito species (Aedes aegypti, Culex quinquefasciatus, Anopheles stephensi, An. culicifacies, An. annularis, An. subpictus, An. vagus). GST activity was assayed spectrophotometrically at 23°C, using a UV Max microplate Reader, to measure the rate of conjugation of GSH to CDNB. A significant species-specific difference in the activity of GST was noticed, highest being in unfed Ae. aegypti (41.2 nmol/min/mg) followed by unfed Cx. quinquefasciatus (7.9 nmol/min/mg) and the least in unfed An. stephensi (5.8 nmol/min/mg). In all the species the GST activity was found to be significantly higher in fully fed and gravid stages compared with the unfed, while the enzyme activity was reduced after egg laying either to the level of unfed animals or well below its level in all the experimental species. The GST activity was found to be higher in the abdominal region of all the experimental species in comparison with the other body parts (head and thorax). The GST activity of An. stephensi increased gradually through the larval stages and reached the maximum level in the pupae and remained at that level in the newly emerged adults. However, its activity declined markedly (10 fold) with ageing from 5 to 40 days. A significant sex-related difference in the specific activity of GST was found in An. stephensi where approximately 3.5 fold lower activity was observed in males compared with its females, whereas no significant variation was noticed in Ae. aegypti and Cx. quinquefasciatus. The study corroborates the fact that GSTs are differentially regulated by multiple mechanisms in response to xenobiotics modulation in situation-specific manner such as species, sex, feeding and developmental stage. The knowledge of situation-specific modulation of GST will provide a better understanding of GST based insecticide resistance

  3. CONTROL DEMONSTRATION OF THE RICEFIELD BREEDING MOSQUITO ANOPHELES ACONITUS DONITZ IN CENTRAL JAVA, USING POECILIA RETICULATA THROUGH COMMUNITY PARTICIPATION : 3. FIELD TRIAL AND EVALUATION

    Directory of Open Access Journals (Sweden)

    Sustriayu Nalim

    2012-09-01

    Full Text Available Suatu penelitian dilakukan untuk menjajagi kemungkinan menggunakan minapadi sebagai cara pemberantasan nyamuk Anopheles aconitus. Minapadi dilakukan dengan ikan Cyprinus carpio. Dengan tersedianya air di sawah untuk ikan, ikan pemakan jentik Poecilia Reticulata yang ditebarkan dapat hidup pula. Penebaran dilakukan oleh masyarakat. Hasil Penelitian ini menunjukkan bahwa melalui minapadi yaitu dengan penebaran, ikan P. reticulata pada kepadatan 2 ekor /m2, populasi An. aconitus selama 5 tahun dapat diturunkan sebanyak 99,7% dan S.P.R. malaria sebanyak 98.8%. [1] Regency Health Service, Banjarnegara Regency, Central Java.

  4. Infection of the malaria mosquito, Anopheles gambiae, with two species of entomopathogenic fungi: effects of concentration, co-formulation, exposure time and persistence

    NARCIS (Netherlands)

    Mnyone, L.L.; Kirby, M.J.; Lwetoijera, D.W.; Mpingwa, M.W.; Knols, B.G.J.; Takken, W.; Russell, T.L.

    2009-01-01

    Background - Entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana isolates have been shown to infect and reduce the survival of mosquito vectors. Methods - Here four different bioassays were conducted to study the effect of conidia concentration, co-formulation, exposure time and per

  5. Anopheles gambiae odorant binding protein crystal complex with the synthetic repellent DEET: implications for structure-based design of novel mosquito repellents

    OpenAIRE

    Tsitsanou, K. E.; Thireou, T.; Drakou, C. E.; Koussis, K.; Keramioti, M. V.; Leonidas, D. D.; Eliopoulos, E.; Iatrou, K.; Zographos, S. E.

    2012-01-01

    Insect odorant binding proteins (OBPs) are the first components of the olfactory system to encounter and bind attractant and repellent odors emanating from various sources for presentation to olfactory receptors, which trigger relevant signal transduction cascades culminating in specific physiological and behavioral responses. For disease vectors, particularly hematophagous mosquitoes, repellents represent important defenses against parasitic diseases because they effect a reduction in the ra...

  6. The systematic functional analysis of plasmodium protein kinases identifies essential regulators of mosquito transmission

    KAUST Repository

    Tewari, Rita

    2010-10-21

    Although eukaryotic protein kinases (ePKs) contribute to many cellular processes, only three Plasmodium falciparum ePKs have thus far been identified as essential for parasite asexual blood stage development. To identify pathways essential for parasite transmission between their mammalian host and mosquito vector, we undertook a systematic functional analysis of ePKs in the genetically tractable rodent parasite Plasmodium berghei. Modeling domain signatures of conventional ePKs identified 66 putative Plasmodium ePKs. Kinomes are highly conserved between Plasmodium species. Using reverse genetics, we show that 23 ePKs are redundant for asexual erythrocytic parasite development in mice. Phenotyping mutants at four life cycle stages in Anopheles stephensi mosquitoes revealed functional clusters of kinases required for sexual development and sporogony. Roles for a putative SR protein kinase (SRPK) in microgamete formation, a conserved regulator of clathrin uncoating (GAK) in ookinete formation, and a likely regulator of energy metabolism (SNF1/KIN) in sporozoite development were identified. 2010 Elsevier Inc.

  7. Inducible peroxidases mediate nitration of anopheles midgut cells undergoing apoptosis in response to Plasmodium invasion.

    Science.gov (United States)

    Kumar, Sanjeev; Gupta, Lalita; Han, Yeon Soo; Barillas-Mury, Carolina

    2004-12-17

    Plasmodium berghei invasion of Anopheles stephensi midgut cells causes severe damage, induces expression of nitric-oxide synthase, and leads to apoptosis. The present study indicates that invasion results in tyrosine nitration, catalyzed as a two-step reaction in which nitric-oxide synthase induction is followed by increased peroxidase activity. Ookinete invasion induced localized expression of peroxidase enzymes, which catalyzed protein nitration in vitro in the presence of nitrite and H(2)O(2). Histochemical stainings revealed that when a parasite migrates laterally and invades more than one cell, the pattern of induced peroxidase activity is similar to that observed for tyrosine nitration. In Anopheles gambiae, ookinete invasion elicited similar responses; it induced expression of 5 of the 16 peroxidase genes predicted by the genome sequence and decreased mRNA levels of one of them. One of these inducible peroxidases has a C-terminal oxidase domain homologous to the catalytic moiety of phagocyte NADPH oxidase and could provide high local levels of superoxide anion (O(2)), that when dismutated would generate the local increase in H(2)O(2) required for nitration. Chemically induced apoptosis of midgut cells also activated expression of four ookinete-induced peroxidase genes, suggesting their involvement in general apoptotic responses. The two-step nitration reaction provides a mechanism to precisely localize and circumscribe the toxic products generated by defense reactions involving nitration. The present study furthers our understanding of the biochemistry of midgut defense reactions to parasite invasion and how these may influence the efficiency of malaria transmission by anopheline mosquitoes. PMID:15456781

  8. Laboratory observations on the larvicidal efficacy of three plant species against mosquito vectors of malaria, dengue/dengue hemorrhagic fever (DF/DHF) and lymphatic filariasis in the semi-arid desert.

    Science.gov (United States)

    Bansal, S K; Singh, Karam V; Sharma, Sapna; Sherwani, M R K

    2012-05-01

    Comparative larvicidal efficacy of aqueous and organic solvent extracts from seeds, leaves and flowers of three desert plants viz. Calotropis procera (Aiton), Tephrosia purpurea (L.) Pers. and Prosopis juliflora (Sw.) DC. was evaluated against Anopheles stephensi (Liston), Aedes aegypti (Linnaeus) and Culex quinquefasciatus (Say). For this purpose larvae of all the three mosquito species were reared in the laboratory and studies carried out on late 3rd or early 4th instars using standard WHO technique. Based on concentration mortality data 24 and 48 hr LC50and LC90 values along with their 95% fiducial limits, regression equation, chi-square (chi2)/ heterogeneity of the response were determined by log probit regression analysis. Experiments were carried out with different solvent extracts of seeds of C. procera which revealed that methanol (24 hr LC50: 127.2, 194.8, 361.0) and acetone (229.9, 368.1,193.0 mg l(-1)) extracts were more effective with the three mosquito species, respectively. Petroleum ether extract was effective only on An. stephensi while aqueous extracts were not effective at all with any of the mosquito species (mortality seeds of T. purpurea and leaves of P. juliflora were 74.9, 63.2 and 47.0 and 96.2,128.1 and 118.8 mg l(-1) for the above three mosquito species, respectively. Experiments carried out up to 500 mg l-(1) with leaves (T. purpurea) and seeds (P. juliflora) extracts show only up to 10-30% mortality indicating that active larvicidal principle may be present only in the seeds of Tephrosia and leaves of Prosopis. In general, anophelines were found more susceptible than the culicines to the plant derived derivatives. More studies are being carried outon some other desert plants found in this arid region. The study would be of great importance while formulating vector control strategy based on alternative plant based insecticides in this semi-arid region.

  9. Genome landscape and evolutionary plasticity of chromosomes in malaria mosquitoes.

    Directory of Open Access Journals (Sweden)

    Ai Xia

    Full Text Available BACKGROUND: Nonrandom distribution of rearrangements is a common feature of eukaryotic chromosomes that is not well understood in terms of genome organization and evolution. In the major African malaria vector Anopheles gambiae, polymorphic inversions are highly nonuniformly distributed among five chromosomal arms and are associated with epidemiologically important adaptations. However, it is not clear whether the genomic content of the chromosomal arms is associated with inversion polymorphism and fixation rates. METHODOLOGY/PRINCIPAL FINDINGS: To better understand the evolutionary dynamics of chromosomal inversions, we created a physical map for an Asian malaria mosquito, Anopheles stephensi, and compared it with the genome of An. gambiae. We also developed and deployed novel Bayesian statistical models to analyze genome landscapes in individual chromosomal arms An. gambiae. Here, we demonstrate that, despite the paucity of inversion polymorphisms on the X chromosome, this chromosome has the fastest rate of inversion fixation and the highest density of transposable elements, simple DNA repeats, and GC content. The highly polymorphic and rapidly evolving autosomal 2R arm had overrepresentation of genes involved in cellular response to stress supporting the role of natural selection in maintaining adaptive polymorphic inversions. In addition, the 2R arm had the highest density of regions involved in segmental duplications that clustered in the breakpoint-rich zone of the arm. In contrast, the slower evolving 2L, 3R, and 3L, arms were enriched with matrix-attachment regions that potentially contribute to chromosome stability in the cell nucleus. CONCLUSIONS/SIGNIFICANCE: These results highlight fundamental differences in evolutionary dynamics of the sex chromosome and autosomes and revealed the strong association between characteristics of the genome landscape and rates of chromosomal evolution. We conclude that a unique combination of various

  10. Genomic Dark Matter Illuminated: Anopheles Y Chromosomes.

    Science.gov (United States)

    Redmond, Seth N; Neafsey, Daniel E

    2016-08-01

    Hall et al. have strategically used long-read sequencing technology to characterize the structure and highly repetitive content of the Y chromosome in Anopheles malaria mosquitoes. Their work confirms that this important but elusive heterochromatic sex chromosome is evolving extremely rapidly and harbors a remarkably small number of genes.

  11. Genomic Dark Matter Illuminated: Anopheles Y Chromosomes.

    Science.gov (United States)

    Redmond, Seth N; Neafsey, Daniel E

    2016-08-01

    Hall et al. have strategically used long-read sequencing technology to characterize the structure and highly repetitive content of the Y chromosome in Anopheles malaria mosquitoes. Their work confirms that this important but elusive heterochromatic sex chromosome is evolving extremely rapidly and harbors a remarkably small number of genes. PMID:27263828

  12. Experimental hut evaluation of linalool spatial repellent agar gel against Anopheles gambiae sensu stricto mosquitoes in a semi-field system in Bagamoyo, Tanzania

    OpenAIRE

    Tambwe, Mgeni; Mbeyela, Edgar; Massinda, Brian; Moore, Sarah; Maia, Marta

    2014-01-01

    Background Malaria vector control is in need of new tools to face its current challenges such as the spread of pyrethroid-resistance and the increase of outdoor feeding mosquitoes. New strategies such as spatial repellents need to be evaluated as supplemental tools to existing control measures such as insecticide treated bed nets and indoor residual spraying. Linalool is a naturally occurring terpene alcohol commonly found in flowers and spices with reportedly repellent properties. Methods Fo...

  13. Identification and characterization of a novel marine Bacillus cereus for mosquito control.

    Science.gov (United States)

    Poopathi, Subbiah; Mani, C; Thirugnanasambantham, K; Praba, V Lakshmi; Ahangar, Niyaz Ahmad; Balagangadharan, K

    2014-01-01

    Entomopathogenic bacteria to control mosquitoes are a promising environmentally friendly alternative to synthetic pesticides. In the present study, a novel mosquitocidal bacterium was isolated from marine soil collected from east coastal areas at Pondicherry (India). 16S rRNA gene sequence alignment depicted that this isolate belonged to Bacillus cereus VCRC-B520 (NCBI: KC-119192). Biochemical studies on bacterial growth, biomass, and toxin production have revealed that this strain could possibly be helpful in the production of a biopesticide in mosquito control. Toxicity assay with B. cereus against mosquito larvae has shown that the filariasis vector, Culex quinquefasciatus, is more susceptible than the other two species (Anopheles stephensi and Aedes aegypti). The LC50 and LC90 values for C. quinquefasciatus were 0.30 and 2.21 mg/L, respectively. No effect of B. cereus was found on nontargeted organisms. SDS-PAGE analysis and protein purification result from the cell mass of B. cereus have shown that a well-perceptible polypeptide was the dependable factor (85 kDa) for mosquitocidal action. Protein characterization (M/S MALDI-TOF) has shown that it is an endotoxin-specific insecticidal protein, namely "Cry4Aa". Phylogenetic analyses of 16S rDNA gene sequence from this marine isolate have revealed the presence of homology among closely related Bacillus strains. Therefore, considerable interest has been shown on the identification of a potential mosquitocidal bacterium from marine environment (B. cereus), which was not reported earlier in view of the current scenario of the rapid development of resistance to Bacillus sphaericus in mosquito vector control program.

  14. THE MINAB DAM AND ITS POSSIBLE HAZARDS IN INCREASING MOSQUITO TRANSMITTED DISEASES

    Directory of Open Access Journals (Sweden)

    M.Zaim

    1983-06-01

    Full Text Available A one year faunistic study was carried out in Minab area, starting January 1982, to investigate the possible hazards of the newly constructed Minab Dam in increasing the mosquito transmitted diseases. In view of this, a baseline data was gathered by sampling 4th instar mosquito larvae from different kinds of breeding sites, present in Minab area as well as the 4 districts surrounding it. In this program total of 4000 mosquito larvae, from 164 breeding sites, representing 17 species in 4 genera, were collected. Among these species, there were not only those which are of great nuisance due to their biting activity but as well as species which are of great medical and veterinary importance due to their ability to transmit pathogens. The presence of important malaria vector such as Anopheles stephensi, An. dthali, An.superpictus An. Fluviatilis in this area where malaria is still the major public health problem, is of great importance. Also presence of species such as Culex univittatus, Cx. bitaenior hynchus, Cx. tritaeniorhynchus and Aedes caspius can have great consequences due to their role in transmitting arboviriuses present in the area or those brought in by migrating birds, flying from Africa. As a result, any kind of change in species composition, population density, spatial distribution, and mosquito behavior taking place due to the construction and utilization of the Minab Dam can have a major health impact on the human population living in that area and only well planned studies, preferably started before utilization of the Dam, would prevent the possible health hazards associated with it.

  15. One-pot biogenic fabrication of silver nanocrystals using Quisqualis indica: Effectiveness on malaria and Zika virus mosquito vectors, and impact on non-target aquatic organisms.

    Science.gov (United States)

    Govindarajan, Marimuthu; Vijayan, Periasamy; Kadaikunnan, Shine; Alharbi, Naiyf S; Benelli, Giovanni

    2016-09-01

    Currently, mosquito vector control is facing a number of key challenges, including the rapid development of resistance to synthetic pesticides and the recent spread of aggressive arbovirus outbreaks. The biosynthesis of silver nanoparticles (AgNPs) is currently considered an environmental friendly alternative to the employ of pyrethroids, carbamates and microbial agents (e.g. Bacillus thuringiensis var. israelensis), since AgNPs are easy to produce, effective and stable in the aquatic environment. However, their biophysical features showed wide variations according to the botanical agent using for the green synthesis, outlining the importance of screening local floral resources used as reducing and stabilizing agents. In this study, we focused on the biophysical properties and the mosquitocidal action of Quisqualis indica-fabricated AgNPs. AgNPs were characterized using spectroscopic (UV, FTIR, XRD) and microscopic (AFM, SEM, TEM and EDX) techniques. AFM, SEM and TEM confirmed the synthesis of poly-dispersed AgNPs with spherical shape and size ranging from 1 to 30nm. XRD shed light on the crystalline structure of these AgNPs. The acute toxicity of Quisqualis indica extract and AgNPs was evaluated against malaria, arbovirus, and filariasis vectors, Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus, as well as on three important non-target aquatic organisms. The Q. indica leaf extract showed moderate larvicidal effectiveness on Cx. quinquefasciatus (LC50=220.42), Ae. aegypti (LC50=203.63) and An. stephensi (LC50=185.98). Q. indica-fabricated AgNPs showed high toxicity against Cx. quinquefasciatus (LC50=14.63), Ae. aegypti (LC50=13.55) and An. stephensi (LC50=12.52), respectively. Notably, Q. indica-synthesized AgNPs were moderately toxic to non-target aquatic mosquito predators Anisops bouvieri (LC50=653.05μg/mL), Diplonychus indicus (LC50=860.94μg/mL) and Gambusia affinis (LC50=2183.16μg/mL), if compared to the targeted mosquitoes. Overall, the

  16. One-pot biogenic fabrication of silver nanocrystals using Quisqualis indica: Effectiveness on malaria and Zika virus mosquito vectors, and impact on non-target aquatic organisms.

    Science.gov (United States)

    Govindarajan, Marimuthu; Vijayan, Periasamy; Kadaikunnan, Shine; Alharbi, Naiyf S; Benelli, Giovanni

    2016-09-01

    Currently, mosquito vector control is facing a number of key challenges, including the rapid development of resistance to synthetic pesticides and the recent spread of aggressive arbovirus outbreaks. The biosynthesis of silver nanoparticles (AgNPs) is currently considered an environmental friendly alternative to the employ of pyrethroids, carbamates and microbial agents (e.g. Bacillus thuringiensis var. israelensis), since AgNPs are easy to produce, effective and stable in the aquatic environment. However, their biophysical features showed wide variations according to the botanical agent using for the green synthesis, outlining the importance of screening local floral resources used as reducing and stabilizing agents. In this study, we focused on the biophysical properties and the mosquitocidal action of Quisqualis indica-fabricated AgNPs. AgNPs were characterized using spectroscopic (UV, FTIR, XRD) and microscopic (AFM, SEM, TEM and EDX) techniques. AFM, SEM and TEM confirmed the synthesis of poly-dispersed AgNPs with spherical shape and size ranging from 1 to 30nm. XRD shed light on the crystalline structure of these AgNPs. The acute toxicity of Quisqualis indica extract and AgNPs was evaluated against malaria, arbovirus, and filariasis vectors, Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus, as well as on three important non-target aquatic organisms. The Q. indica leaf extract showed moderate larvicidal effectiveness on Cx. quinquefasciatus (LC50=220.42), Ae. aegypti (LC50=203.63) and An. stephensi (LC50=185.98). Q. indica-fabricated AgNPs showed high toxicity against Cx. quinquefasciatus (LC50=14.63), Ae. aegypti (LC50=13.55) and An. stephensi (LC50=12.52), respectively. Notably, Q. indica-synthesized AgNPs were moderately toxic to non-target aquatic mosquito predators Anisops bouvieri (LC50=653.05μg/mL), Diplonychus indicus (LC50=860.94μg/mL) and Gambusia affinis (LC50=2183.16μg/mL), if compared to the targeted mosquitoes. Overall, the

  17. Wash resistance and repellent properties of Africa University mosquito blankets against mosquitoes

    OpenAIRE

    Lukwa, N; A. Makuwaza; T. Chiwade; S.L. Mutambu; M. Zimba; P. Munosiyei

    2013-01-01

    The effect of permethrin-treated Africa University (AU) mosquito blankets on susceptible female Anopheles gambiae sensu lato mosquitoes was studied under laboratory conditions at Africa University Campus in Mutare, Zimbabwe. Wash resistance (ability to retain an effective dose that kills ≥80% of mosquitoes after a number of washes) and repellence (ability to prevent ≥80% of mosquito bites) properties were studied. The AU blankets were wash resistant when 100% mortality was recorded up t...

  18. Comparison of the functional features of the pump organs of Anopheles sinensis and Aedes togoi

    OpenAIRE

    Young-Ran Ha; Seung-Chul Lee; Seung-Jun Seo; Jeongeun Ryu; Dong-Kyu Lee; Sang-Joon Lee

    2015-01-01

    Mosquitoes act as vectors for severe tropical diseases. Mosquito-borne diseases are affected by various factors such as environmental conditions, host body susceptibility, and mosquito feeding behavior. Among these factors, feeding behavior is affected by the feeding pump system located inside the mosquito head and also depends on the species of mosquito. Therefore, the 3D morphological structures of the feeding pumps of Aedes togoi and Anopheles sinensis were comparatively investigated using...

  19. Chemical composition and larvicidal activity of leaf essential oil from Clausena anisata (Willd.)Hook. f. exBenth (Rutaceae) against three mosquito species

    Institute of Scientific and Technical Information of China (English)

    Marimuthu Govindarajan

    2010-01-01

    Objective:To determine the mosquito larvicidal activity of leaf essential oil and their chemical constituents fromClausena anisata(C. anisata) (Willd.) Hook. f. ex Benth. against Culex quinquefasciatus, Aedes aegypti andAnopheles Stephensi.Methods:Essential oil was obtained by hydro-distillation and the chemical composition of the leaf essential oil was analyzed using gas chromatography-mass spectrometry. The mosquitoes were reared in the vector control laboratory and twenty late III instar larvae of three mosquito species were exposed to based on the wide range and narrow range tests, essential oil was tested at50, 100, 150, 200 and 250 ppm and each compound was tested at various concentration (5-75 ppm) and were assayed in the laboratory by using the protocol ofWHO 2005; the 24 hLC50 values of theC. anisata leaf essential oil and their major compounds were determined following Probit analysis.Results:The oil contained were mainly β-pinene (32.8%), sabinene(28.3%), germacrene-D (12.7%), estragole (6.4%) and linalool(5.9%). The essential oil from the leaves ofC. anisataexhibited significant larvicidal activity, with24 hLC50 values of140.96, 130.19 and119.59ppm, respectively. The five pure constituents extracted from theC. anisata leaf essential oil were also tested individually against three mosquito larvae. The LC50values of β-pinene, sabinene, germacrene-D, estragole and linalool appeared to be most effective againstAnopheles stephensi(LC50-23.17, 19.67, 16.95, 11.01, 35.17ppm) followed byAedes aegypti (LC50-27.69, 21.20,18.76, 12.70, 38.64 ppm) and Culex quinquefasciatus(LC50-32.23, 25.01, 21.28, 14.01, 42.28).Conclusions:The essential oil of C. anisata contains five major compounds and has remarkable larvicidal properties, which may be considered as a potent source for the production of natural larvicides.

  20. Anopheles darlingi and Anopheles marajoara (Diptera: Culicidae susceptibility to pyrethroids in an endemic area of the Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Allan Kardec Ribeiro Galardo

    2015-12-01

    Full Text Available Abstract: INTRODUCTION: This study aimed to evaluate the susceptibility of Anopheles darlingi Root (1926 and Anopheles marajoara Galvão & Damasceno (1942 to pyrethroids used by the National Malaria Control Program in Brazil. METHODS: Mosquitoes from Amapá, Brazilian Amazon, were assessed for resistance to cypermethrin, deltamethrin, and alpha-cypermethrin. Insecticide-impregnated bottles were used as suggested by the CDC/Atlanta. RESULTS: Diagnostic dose for Anopheles darlingi was 12.5µg/bottle during 30 min of exposure. Concentrations for Anopheles marajoara were 20µg/bottle of cypermethrin and deltamethrin and 12.5µg/bottle of alpha-cypermethrin. CONCLUSIONS : No resistance was recorded for Anopheles darlingi , but Anopheles marajoara requires attention.

  1. Identification of the Temperature Induced Larvicidal Efficacy of Agave angustifolia against Aedes, Culex, and Anopheles Larvae.

    Science.gov (United States)

    Kajla, Mithilesh; Bhattacharya, Kurchi; Gupta, Kuldeep; Banerjee, Ujjwal; Kakani, Parik; Gupta, Lalita; Kumar, Sanjeev

    2015-01-01

    Synthetic insecticides are generally employed to control the mosquito population. However, their injudicious over usage and non-biodegradability are associated with many adverse effects on the environment and mosquitoes. The application of environment-friendly mosquitocidals might be an alternate to overcome these issues. In this study, we found that organic or aqueous extracts of Agave angustifolia leaves exhibited a strong larvicidal activity (LD50 28.27 μg/ml) against Aedes aegypti, Culex quinquefasciatus, and Anopheles stephensi larvae within a short exposure of 12 h. The larvicidal activity of A. angustifolia is inherited and independent of the plants vegetative growth. Interestingly, the plant larvicidal activity was observed exclusively during the summer season (April-August, when outside temperature is between 30 and 50°C) and it was significantly reduced during winter season (December-February, when the outside temperature falls to ~4°C or lower). Thus, we hypothesized that the larvicidal components of A. angustifolia might be induced by the manipulation of environmental temperature and should be resistant to the hot conditions. We found that the larvicidal activity of A. angustifolia was induced when plants were maintained at 37°C in a semi-natural environment against the controls that were growing outside in cold weather. Pre-incubation of A. angustifolia extract at 100°C for 1 h killed 60% larvae in 12 h, which gradually increased to 100% mortality after 24 h. In addition, the dry powder formulation of A. angustifolia, also displayed a strong larvicidal activity after a long shelf life. Together, these findings revealed that A. angustifolia is an excellent source of temperature induced bioactive metabolites that may assist the preparedness for vector control programs competently. PMID:26793700

  2. Identification of the temperature- induced larvicidal efficacy of Agave angustifolia against Aedes, Culex and Anopheles larvae

    Directory of Open Access Journals (Sweden)

    Mithilesh eKajla

    2016-01-01

    Full Text Available Synthetic insecticides are generally employed to control the mosquito population. However, their injudicious over usage and non-biodegradability are associated with many adverse effects on the environment and mosquitoes. The application of environment-friendly mosquitocidals might be an alternate to overcome these issues. In this study, we found that organic or aqueous extracts of Agave angustifolia leaves exhibited a strong larvicidal activity (LD50 28.27 µg/ml against Aedes aegypti, Culex quinquefasciatus and Anopheles stephensi larvae within a short exposure of 12h. The larvicidal activity of Agave angustifolia is inherited and independent of the plants vegetative growth. Interestingly, the plant larvicidal activity was observed exclusively during the summer season (April-August, when outside temperature is between 30oC to 50oC and it was significantly reduced during winter season (December-February, when the outside temperature falls to ~4oC or lower. Thus, we hypothesized that the larvicidal components of Agave angustifolia might be induced by the manipulation of environmental temperature and should be resistant to the hot conditions. We found that the larvicidal activity of Agave angustifolia was induced when plants were maintained at 37oC in a semi-natural environment against the controls that were growing outside in cold weather. Pre-incubation of Agave angustifolia extract at 100oC for 1h killed 60% larvae in 12h, which gradually increased to 100% mortality after 24h. In addition, the dry powder formulation of Agave angustifolia, also displayed a strong larvicidal activity after a long shelf life. Together, these findings revealed that Agave angustifolia is an excellent source of temperature induced bioactive metabolites that may assist the preparedness for vector control programs competently.

  3. Mermithid nematodes found in adult Anopheles from southeastern Senegal

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    Kobylinski Kevin C

    2012-06-01

    Full Text Available Abstract Background Over two dozen mermithid nematodes have been described parasitizing mosquitoes worldwide, however, only two species were found in Africa. Mermithid nematodes kill their mosquito host upon emergence, which suggests that they could be developed as biological control agents of mosquitoes. Both Romanomermis culicivorax and Romanomermis iyengari have been reared for mass release to control numerous Anopheles species vector populations, and in one instance this may have led to reduced malaria prevalence in a human population. Methods Anopheles mosquitoes were collected during a malaria study in southeastern Senegal. Two different adult blood fed mosquitoes had a single mermithid nematode emerge from their anus while they were being held post-capture. Primers from the 18 S rDNA were developed to sequence nematode DNA and screen mosquitoes for mermithid DNA. 18 S rDNA from the Senegalese mermithid and other mermithid entries in GenBank were used to create a Maximum Parsimony tree of the Mermithidae family. Results The mermithid was present in 1.8% (10/551 of the sampled adult Anopheles species in our study area. The mermithid was found in An. gambiae s.s., An. funestus, and An. rufipes from the villages of Ndebou, Boundoucondi, and Damboucoye. Maximum parsimony analysis confirmed that the nematode parasites found in Anopheles were indeed mermithid parasites, and of the mermithid sequences available in GenBank, they are most closely related to Strelkovimermis spiculatus. Conclusions To our knowledge, this is the first report of mermithids from adult Anopheles mosquitoes in Senegal. The mermithid appears to infect Anopheles mosquitoes that develop in diverse larval habitats. Although maximum parsimony analysis determined the mermithid was closely related to Strelkovimermis spiculatus, several characteristics of the mermithid were more similar to the Empidomermis genus. Future mermithid isolations will hopefully allow: formal

  4. Neem by-products in the fight against mosquito-borne diseases:Biotoxicity of neem cake fractions towards the rural malaria vector Anopheles culicifacies (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Balamurugan Chandramohan; Marcello Nicoletti; Angelo Canale; Giovanni Benelli; Kadarkarai Murugan; Pari Madhiyazhagan; Kalimuthu Kovendan; Palanisamy Mahesh Kumar; Chellasamy Panneerselvam; Devakumar Dinesh; Jayapal Subramaniam; Rajapandian Rajaganesh

    2016-01-01

    Objective: To evaluate the ovicidal, larvicidal and adulticidal potential of neem cake fractions of different polarity against the rural malaria vector Anopheles culicifacies (An. culicifacies). Methods: Neem cake fractions' total methanol extract (NTMeOH), total ethyl acetate extract (NTAcOEt), ethyl acetate fraction after repartition with NTMeOH (NRAcOEt), butanol fraction after repartition with NTMeOH (NRBuOH), and aqueous fraction after repartition of NTMeOH (NRH2O) were tested against An. culicifacies eggs, fourth instar larvae and adults. Results: In larvicidal experiments, NTMeOH, NTAcOEt, NRAcOEt, NRBuOH and NRH2O achieved LC50 values of 1.32, 1.50, 1.81, 1.95 and 2.54 mg/L, respectively. All fractions tested at 150 mg/L were able to reduce egg hatchability of more than 50%, with the exception of NTAcOEt and NRAcOEt. In adulticidal assays, NTMeOH, NTAcOEt, NRAcOEt, NRBuOH and NRH2O achieved LC50 values of 3.01, 2.95, 3.23, 3.63 and 3.00 mg/L, respectively. Conclusions: Overall, this study suggests that the methanolic fractions of neem cake may be considered as a new and cheap source of highly effective compounds against the rural malaria vector An. culicifacies.

  5. Barrier screens: a method to sample blood-fed and host-seeking exophilic mosquitoes

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    Burkot Thomas R

    2013-02-01

    Full Text Available Abstract Background Determining the proportion of blood meals on humans by outdoor-feeding and resting mosquitoes is challenging. This is largely due to the difficulty of finding an adequate and unbiased sample of resting, engorged mosquitoes to enable the identification of host blood meal sources. This is particularly difficult in the south-west Pacific countries of Indonesia, the Solomon Islands and Papua New Guinea where thick vegetation constitutes the primary resting sites for the exophilic mosquitoes that are the primary malaria and filariasis vectors. Methods Barrier screens of shade-cloth netting attached to bamboo poles were constructed between villages and likely areas where mosquitoes might seek blood meals or rest. Flying mosquitoes, obstructed by the barrier screens, would temporarily stop and could then be captured by aspiration at hourly intervals throughout the night. Results In the three countries where this method was evaluated, blood-fed females of Anopheles farauti, Anopheles bancroftii, Anopheles longirostris, Anopheles sundaicus, Anopheles vagus, Anopheles kochi, Anopheles annularis, Anopheles tessellatus, Culex vishnui, Culex quinquefasciatus and Mansonia spp were collected while resting on the barrier screens. In addition, female Anopheles punctulatus and Armigeres spp as well as male An. farauti, Cx. vishnui, Cx. quinquefasciatus and Aedes species were similarly captured. Conclusions Building barrier screens as temporary resting sites in areas where mosquitoes were likely to fly was an extremely time-effective method for collecting an unbiased representative sample of engorged mosquitoes for determining the human blood index.

  6. Wide cross-reactivity between Anopheles gambiae and Anopheles funestus SG6 salivary proteins supports exploitation of gSG6 as a marker of human exposure to major malaria vectors in tropical Africa

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    Petrarca Vincenzo

    2011-07-01

    Full Text Available Abstract Background The Anopheles gambiae gSG6 is an anopheline-specific salivary protein which helps female mosquitoes to efficiently feed on blood. Besides its role in haematophagy, gSG6 is immunogenic and elicits in exposed individuals an IgG response, which may be used as indicator of exposure to the main African malaria vector A. gambiae. However, malaria transmission in tropical Africa is sustained by three main vectors (A. gambiae, Anopheles arabiensis and Anopheles funestus and a general marker, reflecting exposure to at least these three species, would be especially valuable. The SG6 protein is highly conserved within the A. gambiae species complex whereas the A. funestus homologue, fSG6, is more divergent (80% identity with gSG6. The aim of this study was to evaluate cross-reactivity of human sera to gSG6 and fSG6. Methods The A. funestus SG6 protein was expressed/purified and the humoral response to gSG6, fSG6 and a combination of the two antigens was compared in a population from a malaria hyperendemic area of Burkina Faso where both vectors were present, although with a large A. gambiae prevalence (>75%. Sera collected at the beginning and at the end of the high transmission/rainy season, as well as during the following low transmission/dry season, were analysed. Results According to previous observations, both anti-SG6 IgG level and prevalence decreased during the low transmission/dry season and showed a typical age-dependent pattern. No significant difference in the response to the two antigens was found, although their combined use yielded in most cases higher IgG level. Conclusions Comparative analysis of gSG6 and fSG6 immunogenicity to humans suggests the occurrence of a wide cross-reactivity, even though the two proteins carry species-specific epitopes. This study supports the use of gSG6 as reliable indicator of exposure to the three main African malaria vectors, a marker which may be useful to monitor malaria transmission

  7. Susceptibility of Culicidae Mosquitoes to Some Insecticides Recommended by WHO in a Malaria Endemic Area of Southeastern Iran

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    Mousa Fathian

    2015-10-01

    Full Text Available Background: According to the national strategy plan on monitoring of insecticides resistance, this study was carried out to determine the base line susceptibility of the Culicidae mosquitoes to the WHO-recommended insecticides in an endemic focus of malaria in southeastern Iran.Methods: Larval collection was carried out by dipping method and adult collection occurred by suction tube from January to December 2010. The susceptibility test was assessed to DDT 4 %, malathion 5 %, propoxur 0.1 %, deltamethrin 0.05 %, lambda-cyhalothrin 0.05 %, and cyfluthrin 0.15 % at different interval times (discriminative dose followed by 24 h recovery period . The LT50 and LT90 values were calculated for plotting the regression line using Microsoft office Excel software ver. 2007.Results: Anopheles stephensi was quite resistant to DDT and showed susceptible or tolerant to other insecticides. The LT50 and LT90 values to DDT in this species were 29.07, and 98.26 minutes, respectively. Anopheles culicifacies and Anopheles dthali were found susceptible or tolerant to insecticides. Culex pipiens was found resistance to DDT, propoxur, lambda-cyhalothrin and cyfluthrin whereas observed susceptible to malathion and tolerant to deltamethrin. Ochlerotatus caspius sl. was resistant to DDT, whereas found susceptible to other insecticides. Culisita longiareolatawas susceptible to deltamethrin, whereas tolerant to other insecticides. The LT50 and LT90 values of Cs. longiareolata to DDT were 17.82, and 51.26 minutes.Conclusion: We suggested the same study in different parts of the country for monitoring and evaluation of control measures.

  8. Spatial and temporal distribution of the malaria mosquito Anopheles arabiensis in northern Sudan: influence of environmental factors and implications for vector control

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    Malcolm Colin A

    2009-06-01

    Full Text Available Abstract Background Malaria is an important public health problem in northern Sudan, but little is known about the dynamics of its transmission. Given the characteristic low densities of Anopheles arabiensis and the difficult terrain in this area, future vector control strategies are likely to be based on area-wide integrated pest management (AW-IPM that may include the sterile insect technique (SIT. To support the planning and implementation of future AW-IPM activities, larval surveys were carried out to provide key data on spatial and seasonal dynamics of local vector populations. Methods Monthly cross-sectional larval surveys were carried out between March 2005 and May 2007 in two localities (Dongola and Merowe adjacent to the river Nile. A stratified random sampling strategy based on the use of Remote Sensing (RS, Geographical Information Systems (GIS and the Global Positioning System (GPS was used to select survey locations. Breeding sites were mapped using GPS and data on larval density and breeding site characteristics were recorded using handheld computers. Bivariate and multivariate logistic regression models were used to identify breeding site characteristics associated with increased risk of presence of larvae. Seasonal patterns in the proportion of breeding sites positive for larvae were compared visually to contemporaneous data on climate and river height. Results Of a total of 3,349 aquatic habitats sampled, 321 (9.6% contained An. arabiensis larvae. The frequency with which larvae were found varied markedly by habitat type. Although most positive sites were associated with temporary standing water around the margins of the main Nile channel, larvae were also found at brickworks and in areas of leaking pipes and canals – often far from the river. Close to the Nile channel, a distinct seasonal pattern in larval populations was evident and appeared to be linked to the rise and fall of the river level. These patterns were not

  9. Bionomics of Anopheles spp. (Diptera: Culicidae) in a malaria endemic region of Sukabumi, West Java, Indonesia.

    Science.gov (United States)

    Stoops, Craig A; Rusmiarto, Saptoro; Susapto, Dwiko; Munif, Amurl; Andris, Heri; Barbara, Kathryn A; Sukowati, Supratman

    2009-12-01

    A 15-month bionomic study of Anopheles species was conducted in two ecologically distinct villages (coastal and upland) of Sukabumi District, West Java, Indonesia from June 2006 to September 2007. Mosquitoes were captured using human-landing collections at both sites. During the study, a total of 17,100 Anopheles mosquitoes comprising 13 Anopheles species were caught: 9,151 at the coastal site and 7,949 at the upland site. Anopheles barbirostris, Anopheles maculatus, and Anopheles vagus were the predominant species caught at the coastal site, and Anopheles aconitus, Anopheles barbirostris, and An. maculatus predominated in the upland site. Overall, species were exophagic at both sites, but there was variation between species. Anopheles aconitus was endophagic at the coastal site, exophagic at the upland site, collected most often in April 2007 and had a peak landing time between 22:00 and 23:00. Anopheles sundaicus was only collected at the coastal site, exophagic, collected most often in October 2006, and had a peak landing time between 19:00 and 20:00. Potential malaria vector species such An. aconitus, An. maculatus, and An. sundaicus were present throughout the year. None of the 7,770 Anopheles tested using CSP-ELISA were positive for malaria, although the risk for malaria outbreaks in Sukabumi district remains high.

  10. The ecology and larval habitats characteristics of anopheline mosquitoes (Diptera:Culicidae) in Aligudarz County (Luristan province, western Iran)

    Institute of Scientific and Technical Information of China (English)

    Hamid Amani; Mohammad Reza Yaghoobi-Ershadi; Hamid Kassiri

    2014-01-01

    Objective: To determine ecology and characteristics of the larval habitats of the genus Anopheles (Dipetra: Culicidae) in Aligudarz County, western Iran.Methods:larvae ecology in seven rural districts, Aligudarz County, from late April to late November 1997. Larvae were captured using the dipping method. Larval breeding places characteristics were noted according to water situation (turbid or clean, stagnant or running), substrate type, site type (man-made or natural), sunlight situation, site situation (transient or permanent, with or without vegetation). This descriptive cross-sectional research was carried out to study the anopheline Results: A total of 9 620 3rd and 4th instar larvae of Anopheles from 115 breeding places in 22 villages were captured, which belonged to the following species: Anopheles stephensi, Anopheles d’thali, Anopheles apoci, Anopheles superpictus (forms A and B), Anopheles marterii sogdianus, Anopheles turkhodi, Anopheles maculipennis S.L and Anopheles claviger. Anopheles stephensi,Anopheles maculipennis Anopheles superpictus (93.18%) was the most prevailed one and dispersed over the entire region. Larval habitats consisted of nine natural and three artificial larval habitats. The most important larval habitats were river edges (54.8%), rice fields (12.2%), and grassland (8.7%) with permanent or transient, stagnant or running and clean water, with or without vegetation, sand or mud substrate in full sunlight area.Conclusions:Regarding this research, river edges and rice fields are the most important S.L and Anopheles apoci were collected for the first time in this county. breeding places of malaria vectors in Aligudarz County. It is worthy of note in larvicidal programs.

  11. The role of reactive oxygen species on Plasmodium melanotic encapsulation in Anopheles gambiae

    OpenAIRE

    Kumar, Sanjeev; Christophides, George K.; Cantera, Rafael; Charles, Bradley; Han, Yeon Soo; Meister, Stephan; Dimopoulos, George; Kafatos, Fotis C.; Barillas-Mury, Carolina

    2003-01-01

    Malaria transmission depends on the competence of some Anopheles mosquitoes to sustain Plasmodium development (susceptibility). A genetically selected refractory strain of Anopheles gambiae blocks Plasmodium development, melanizing, and encapsulating the parasite in a reaction that begins with tyrosine oxidation, and involves three quantitative trait loci. Morphological and microarray mRNA expression analysis suggest that the refractory and susceptible strains have broad physiological differe...

  12. Biting patterns and host preference of Anopheles epiroticus in Chang Island, Trat Province, Eastern Thailand

    OpenAIRE

    Ritthison, W.; Tainchum, K.; Manguin, Sylvie; Bangs, M.J.; Chareonviriyaphap, T.

    2014-01-01

    A study of species diversity of Anopheles mosquitoes, biting patterns, and seasonal abundance of important mosquito vectors was conducted in two villages of Chang Island, Trat Province, in eastern Thailand, one located along the coast and the other in the low hills of the central interior of the island. Of 5,399 captured female anophelines, 70.25% belong to the subgenus Cellia and remaining specimens to the subgenus Anopheles. Five important putative malaria vectors were molecularly identifie...

  13. The role of mosquito behaviour on parasite transmission

    OpenAIRE

    Ma, Brian Oh-Bong

    2010-01-01

    I use a combination of theory and experiments to explore the role of various aspects of mosquito behaviour on the ability of mosquitoes to transmit parasites. Special focus is given to the mosquito Anopheles gambiae s.s., the principal vector for Plasmodium falciparum, a parasite that causes human malaria. Female mosquitoes require host blood for egg production, but also use sugar from nectar sources; however, the extent of sugar use is poorly understood. Sugar can be used to fuel somatic mai...

  14. Paratransgenesis: a promising new strategy for mosquito vector control

    OpenAIRE

    Wilke, André Barretto Bruno; Marrelli, Mauro Toledo

    2015-01-01

    The three main mosquito genera, Anopheles, Aedes and Culex, transmit respectively malaria, dengue and lymphatic filariasis. Current mosquito control strategies have proved unsuccessful, and there still is a substantial number of morbidity and mortality from these diseases. Genetic control methods have now arisen as promising alternative strategies, based on two approaches: the replacement of a vector population by disease-refractory mosquitoes and the release of mosquitoes carrying a lethal g...

  15. Fitness of anopheline mosquitoes expressing transgenes that inhibit Plasmodium development.

    OpenAIRE

    Moreira, Luciano A.; Jing WANG; Collins, Frank H.; Jacobs-Lorena, Marcelo

    2004-01-01

    One potential strategy for the control of malaria and other vector-borne diseases is the introduction into wild vector populations of genetic constructs that reduce vectorial capacity. An important caveat of this approach is that the genetic construct should have minimal fitness cost to the transformed vector. Previously, we produced transgenic Anopheles stephensi expressing either of two effector genes, a tetramer of the SM1 dodecapeptide or the phospholipase A2 gene (PLA2) from honeybee ven...

  16. Synergistic effect of some essential oils on toxicity and knockdown effects, against mosquitos, cockroaches and housefly

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    Idin Zibaee

    2015-12-01

    Full Text Available The toxicity and knockdown effect of Eucalyptus globulus, Rosmarinus officinalis essential oils and their mixed formulation on Periplaneta Americana (L., Blattella germanica (L., Supella longipalpa, Culex pipiens, Anopheles stephensi and Musca domestica were evaluated in a series of laboratory experiments. In all bioassay five different doses (0.625, 1.25, 2.5, 5 and 10% were used by filter paper (cm2 and aerosol (cm3 bioassay methods, all essential oils was toxic to cockroaches, mosquitos and housefly species the lowest and the highest LC50 belong to mixed formulation on B. germanica (LC50 6.1 and E. globulus on P. americana (LC50 27.7 respectively. In continuous exposure experiments, Mortality (LT50 values for cockroaches ranged from 1403.3 min with 0.625% E. globulus (for P. americana to 2.2 min with 10% mixed formulation for A. stephensi. The KT50 values ranged from 0.1 to 1090.8 min for 10% and 0.625 for mixed formulation and R. officinalis respectively. The mortality after 24 h for mixed formulation was 100% but for single essential oils ranged from 81.5 to 98.3 for P. americana treated with R. officinalis and A. stephensi treated with E. globulus respectively. Studies on persistence of essential oils on impregnated paper revealed that it has more adulticidal activity for longer period at low storage temperature. Gas chromatographic-mass spectrometric analysis of essential oil showed 14 and 16 peaks for E. globules and R. officinalis respectively. α-Pinene (39.8%, 1, 8-Cineole (13.2%, Camphene (9.1% and Borneol (3.7% were present in major amounts for R. officinalis and 1,8-Cineole (31.4%, α-Pinene (15.3%, d-Limonene (9.7% and α-Terpinolen (5.3% were present in major amounts for E. globulus respectively. Our results showed that two surveyed essential oils has compatible with synergistic effect on various insect species, furthermore it is useful for applying as integrated pest management tool for studied insects management, especially in

  17. Control of pyrethroid and DDT-resistant Anopheles gambiae by application of indoor residual spraying or mosquito nets treated with a long-lasting organophosphate insecticide, chlorpyrifos-methyl

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    Chabi Joseph

    2010-02-01

    Full Text Available Abstract Background Scaling up of long-lasting insecticidal nets (LLINs and indoor residual spraying (IRS with support from the Global Fund and President's Malaria Initiative is providing increased opportunities for malaria control in Africa. The most cost-effective and longest-lasting residual insecticide DDT is also the most environmentally persistent. Alternative residual insecticides exist, but are too short-lived or too expensive to sustain. Dow Agrosciences have developed a microencapsulated formulation (CS of the organophosphate chlorpyrifos methyl as a cost-effective, long-lasting alternative to DDT. Methods Chlorpyrifos methyl CS was tested as an IRS or ITN treatment in experimental huts in an area of Benin where Anopheles gambiae and Culex quinquefasiactus are resistant to pyrethroids, but susceptible to organophosphates. Efficacy and residual activity was compared to that of DDT and the pyrethroid lambdacyalothrin. Results IRS with chlorpyrifos methyl killed 95% of An. gambiae that entered the hut as compared to 31% with lambdacyhalothrin and 50% with DDT. Control of Cx. quinquefasciatus showed a similar trend; although the level of mortality with chlorpyrifos methyl was lower (66% it was still much higher than for DDT (14% or pyrethroid (15% treatments. Nets impregnated with lambdacyhalothrin were compromized by resistance, killing only 30% of An. gambiae and 8% of Cx. quinquefasciatus. Nets impregnated with chlorpyrifos methyl killed more (45% of An gambiae and 15% of Cx. quinquefasciatus, but its activity on netting was of short duration. Contact bioassays on the sprayed cement-sand walls over the nine months of monitoring showed no loss of activity of chlorpyrifos methyl, whereas lambdacyhalothrin and DDT lost activity within a few months of spraying. Conclusion As an IRS treatment against pyrethroid resistant mosquitoes chlorpyrifos methyl CS outperformed DDT and lambdacyhalothrin. In IRS campaigns, chlorpyrifos methyl CS should

  18. Status of carbohydrate, protein and lipid profile in the mosquito larvae treated with certain phytoextracts

    Institute of Scientific and Technical Information of China (English)

    Preeti Sharma; Lalit Mohan; Kamal Kumar Dua; Chand Narayan Srivastava

    2011-01-01

    Objective:To investigate the impact of the most potent petroleum ether extract ofArtemisia annua (A. annua) andAzadirachta indica (Az. indica) on total carbohydrate, lipid and protein level ofAnopheles stephensi andCulex quinquefasciatuslarvae.Methods: Mosquito larvae were exposed to the extracts selected as per standardWHO procedure. Carbohydrate (glucose), total lipid and protein were estimated by the methods as Nelson, Bragdon and Lowry described, respectively.Results: The glucose levels were increased to27.87% and46.8%, respectively in anopheline larval tissues after treatment with petroleum ether extract ofA. annua and methanolic extract ofAz. indica. In culicine larvae, glucose levels were reduced to58.96% and24.65%, respectively. After treatment withA. annua extract, lipid contents in anopheline and culicine larvae decreased by28.57% and25.0%, respectively and increased by14.29% and50.00% in theAnopheles andCulex larvae, respectively after treatment with methanolic extract ofAz. indica. Total protein levels were reduced to63.13% and92.62% in anopheline and to32.39% and 48.12% in culicine larvae after treatment withA. annua andAz. Indica extracts, respectively. Conclusions: Two extracts produce significant alterations in the biochemical profiles of anopheline and culicine larvae. Further, the impacting factors of extracts on carbohydrate, lipid and protein contents of larvae are species and specific extraction. It indicates the disturbed metabolic activity of the larvae.