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Biochemical synthetic pyrethroids, deltamethrin are presently used insecticides for the control of mosquito vector-borne diseases in worldwide. Mosquito re-emergence with diseases becoming a serious problem due to development of insecticide resistance. The comprehensive knowledge on the underlying mechanisms of resistance against deltamethrin is required for implementation of an efficient vector control programme. The assessment of the biological fitness of a mosquito strain exposed to insecticide pressure is extremely vital because it provides information on the development of resistance. In the present study, the adult stage of malaria vector, Anopheles stephensi, was designated for the study of deltamethrin resistance (F40 generations). The non-blood-fed, laboratory-reared females to sub-lethal doses of deltamethrin (0.004%, 0.005%, 0.007%, or 0.01%) exposed to every generation for up to F40. The adult mosquito susceptibility was performed by WHO standard method for evaluation. After 24 h, mortality was recorded in both treated and control groups. Therefore, the biological fitness characteristics such as feeding, fecundity, hatchability, egg retention, immature duration, adult emergence, and adult life span were studied to assess the exposed deltamethrin under selection pressure as compared to the unexposed (control) population. The laboratory selection of An. stephensi exposed deltamethrin over the generations were diminished its biological fitness. Information on biological fitness including reproductive potential of mosquito strain under selection pressure against deltamethrin is incredibly necessary because it would facilitate in resistance management. Baseline information gives in this experiment will guide for future studies on the susceptibilities of wild malaria mosquito populations in India., Competing Interests: Declarations Ethics approval Not applicable. Consent to participate Informed consent was obtained from all individual participants included in this study. Consent for publication The participants have given their consent to submit this manuscript in this esteemed journal. Conflict of interest The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Mosquitoes are insects of huge public health importance, since they act as vectors for important pathogens and parasites. Here, we focused on the possibility of using the neem cake in the fight against mosquito vectors. The neem cake chemical composition significantly changes among producers, as evidenced by our HPTLC (High performance thin layer chromatography) analyses of different marketed products. Neem cake extracts were tested to evaluate the ovicidal, larvicidal and adulticidal activity against the rural malaria vector Anopheles culicifacies. Ovicidal activity of both types of extracts was statistically significant, and 150 ppm completely inhibited egg hatching. LC 50 values were extremely low against fourth instar larvae, ranging from 1.321 (NM1) to 1.818 ppm (NA2). Adulticidal activity was also high, with LC 50 ranging from 3.015 (NM1) to 3.637 ppm (NM2). This study pointed out the utility of neem cake as a source of eco-friendly mosquitocides in Anopheline vector control programmes.

Mosquito-borne diseases represent a deadly threat for millions of people worldwide. According to recent estimates, about 3.2 billion people, almost half of the world's population, are at risk of malaria. Malaria control is particularly challenging due to a growing number of chloroquine-resistant Plasmodium and pesticide-resistant Anopheles vectors. Newer and safer control tools are required. In this research, gold nanoparticles (AuNPs) were biosynthesized using a cheap flower extract of Couroupita guianensis as reducing and stabilizing agent. The biofabrication of AuNP was confirmed by UV-vis spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) spectroscopy, X-ray diffraction (XRD), zeta potential, and particle size analysis. AuNP showed different shapes including spheres, ovals, and triangles. AuNPs were crystalline in nature with face-centered cubic geometry; mean size was 29.2-43.8 nm. In laboratory conditions, AuNPs were toxic against Anopheles stephensi larvae, pupae, and adults. LC50 was 17.36 ppm (larva I), 19.79 ppm (larva II), 21.69 ppm (larva III), 24.57 ppm (larva IV), 28.78 ppm (pupa), and 11.23 ppm (adult). In the field, a single treatment with C. guianensis flower extract and AuNP (10 × LC50) led to complete larval mortality after 72 h. In standard laboratory conditions, the predation efficiency of golden wonder killifish, Aplocheilus lineatus, against A. stephensi IV instar larvae was 56.38 %, while in an aquatic environment treated with sub-lethal doses of the flower extract or AuNP, predation efficiency was boosted to 83.98 and 98.04 %, respectively. Lastly, the antiplasmodial activity of C. guianensis flower extract and AuNP was evaluated against CQ-resistant (CQ-r) and CQ-sensitive (CQ-s) strains of Plasmodium falciparum. IC50 of C. guianensis flower extract was 43.21 μg/ml (CQ-s) and 51.16 μg/ml (CQ-r). AuNP IC50 was 69.47 μg/ml (CQ-s) and 76.33 μg/ml (CQ-r). Overall, our results showed the multipurpose effectiveness of C. guianensis-synthesized AuNPs, since they may be proposed as newer and safer tools in the fight against CQ-r strains of P. falciparum and for field control of malaria vectors, in synergy with wonder killifish predators.

Mosquito-borne diseases represent a deadly threat for millions of people worldwide. The Culex genus, with special reference to Culex quinquefasciatus, comprises the most common vectors of filariasis across urban and semi-urban areas of Asia. In recent years, important efforts have been conducted to propose green-synthesized nanoparticles as a valuable alternative to synthetic insecticides. However, the mosquitocidal potential of carbon nanoparticles has been scarcely investigated. In this study, the larvicidal and pupicidal activity of carbon nanoparticle (CNP) and silver nanoparticle (AgNP) was tested against Cx. quinquefasciatus. UV-Vis spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) spectroscopy, and Raman analysis confirmed the rapid and cheap synthesis of carbon and silver nanoparticles. In laboratory assays, LC50 (lethal concentration that kills 50 % of the exposed organisms) values ranged from 8.752 ppm (first-instar larvae) to 18.676 ppm (pupae) for silver nanoparticles and from 6.373 ppm (first-instar larvae) to 14.849 ppm (pupae) for carbon nanoparticles. The predation efficiency of the water bug Lethocerus indicus after a single treatment with low doses of silver and carbon nanoparticles was not reduced. Moderate evidence of genotoxic effects induced by exposure to carbon nanoparticles was found on non-target goldfish, Carassius auratus. Lastly, the plant extract used for silver nanosynthesis was tested for 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity. Overall, our results pointed out that AgNP and CNP can be a candidate for effective tools to reduce larval and pupal populations of filariasis vectors, with reduced genotoxicity and impact on behavioral traits of other aquatic organisms sharing the same ecological niche of Cx. quinquefasciatus.

Mosquitoes (Diptera: Culicidae) serve as important vectors for a wide number of parasites and pathogens of huge medical and veterinary importance. Aedes aegypti is a primary dengue vector in tropical and subtropical urban areas. There is an urgent need to develop eco-friendly mosquitocides. In this study, silver nanoparticles (AgNP) were biosynthesized using neem cake, a by-product of the neem oil extraction from the seed kernels of Azadirachta indica. AgNP were characterized using a variety of biophysical methods, including UV-vis spectrophotometry, FTIR, SEM, EDX, and XRD analyses. Furthermore, the neem cake extract and the biosynthesized AgNP were tested for acute toxicity against larvae and pupae of the dengue vector Ae. aegypti. LC50 values achieved by the neem cake extract ranged from 106.53 (larva I) to 235.36 ppm (pupa), while AgNP LC50 ranged from 3.969 (larva I) to 8.308 ppm (pupa). In standard laboratory conditions, the predation efficiency of a Carassius auratus per day was 7.9 (larva II) and 5.5 individuals (larva III). Post-treatment with sub-lethal doses of AgNP, the predation efficiency was boosted to 9.2 (larva II) and 8.1 individuals (larva III). The genotoxic effect of AgNP was studied on C. auratus using the comet assay and micronucleus frequency test. DNA damage was evaluated on peripheral erythrocytes sampled at different time intervals from the treatment; experiments showed no significant damages at doses below 12 ppm. Overall, this research pointed out that neem cake-fabricated AgNP are easy to produce, stable over time, and can be employed at low dosages to reduce populations of dengue vectors, with moderate detrimental effects on non-target mosquito natural enemies.

Aedes albopictus is an important arbovirus vector, including dengue. Currently, there is no specific treatment for dengue. Its prevention solely depends on effective vector control measures. In this study, silver nanoparticles (AgNPs) were biosynthesized using a cheap leaf extract of Berberis tinctoria as reducing and stabilizing agent and tested against Ae. albopictus and two mosquito natural enemies. AgNPs were characterized by using UV–vis spectrophotometry, X-ray diffraction, and scanning electron microscopy. In laboratory conditions, the toxicity of AgNPs was evaluated on larvae and pupae of Ae. albopictus. Suitability Index/Predator Safety Factor was assessed on Toxorhynchites splendens and Mesocyclops thermocyclopoides. The leaf extract of B. tinctoria was toxic against larval instars (I–IV) and pupae of Ae. albopictus; LC50 was 182.72 ppm (I instar), 230.99 ppm (II), 269.65 ppm (III), 321.75 ppm (IV), and 359.71 ppm (pupa). B. tinctoria-synthesized AgNPs were highly effective, with LC50 of 4.97 ppm (I instar), 5.97 ppm (II), 7.60 ppm (III), 9.65 ppm (IV), and 14.87 ppm (pupa). Both the leaf extract and AgNPs showed reduced toxicity against the mosquito natural enemies M. thermocyclopoides and T. splendens. Overall, this study firstly shed light on effectiveness of B. tinctoria-synthesized AgNPs as an eco-friendly nanopesticide, highlighting the concrete possibility to employ this newer and safer tool in arbovirus vector control programs.

Background: Plant synthesized silver nanoparticles give rapid control on mosquito larvae of dengue vector, Aedes albopictus. AgNPs synthesized from the plant, Argemone mexicana for the control of larvae and these nanoparticles inhibit the growth of microbes are broad spectrum of nanoparticle activities., Methods: Nanoparticles were subjected to analysis by UV-vis spectrophotometry, Fourier transform infrared spectroscopy, scanning electron microscopy and transmission electron microscopy. Furthermore, laboratory evaluation of plant mediated nano-particle carried out lethal toxicity on Aedes albopictus. The characterization studies confirmed the spherical shape and size (5-50 nm) of silver nano-particles., Results: The efficacy of AgNPs was tested at concentration of 2 to 10 ppm against L1 to L4 larval instar of A. albopictus. The LC50 followed by LC90 values were (L1) 5.24, 8.66; (L2) 5.56, 8.85; (L3) 6.20, 10.01 and (L4) 7.04, 10.92 at 10 ppm of silver nanoparticle, whereas LC50 (LC90) values of (L1) 7.63, 11.58; (L2) 8.17, 11.88; 8.80, 12.82 and 8.94, 12.26 at 10 ppm of plant extract alone treated larvae, respectively. The mortality rates were positively correlated with the concentration of AgNPs. Significant (P<0.05) high square value changes in the larval mortality were also recorded between the period of exposure against all larval instar of A. albopictus. Silver nanoparticles were also tested for antimicrobial activity and significant toxicity inhibition was observed against the gram positive microbes and it exhibited mild toxicity against P. aeroginosa., Conclusion: Plant, A. mexicana synthesized silver nano-particles are rapid and potential mosquito larvicidal as well as antimicrobial agents. Finding of our results support that silver nanoparticles can be prepared in a simple and cost-effective manner and are suitable for bio-formulation against mosquitoes and microbes.

Mosquito-borne diseases represent a deadly threat for millions of people worldwide. However, the use of synthetic insecticides to control Culicidae may lead to high operational costs and adverse non-target effects. Plant-borne compounds have been proposed for rapid extracellular synthesis of mosquitocidal nanoparticles. Their impact against biological control agents of mosquito larval populations has been poorly studied. We synthesized silver nanoparticles (AgNP) using the aqueous leaf extract of Mimusops elengi as a reducing and stabilizing agent. The formation of AgNP was studied using different biophysical methods, including UV-vis spectrophotometry, TEM, XRD, EDX and FTIR. Low doses of AgNP showed larvicidal and pupicidal toxicity against the malaria vector Anopheles stephensi and the arbovirus vector Aedes albopictus. AgNP LC50 against A. stephensi ranged from 12.53 (I instar larvae) to 23.55 ppm (pupae); LC50 against A. albopictus ranged from 11.72 ppm (I) to 21.46 ppm (pupae). In the field, the application of M. elengi extract and AgNP (10 × LC50) led to 100 % larval reduction after 72 h. In adulticidal experiments, AgNP showed LC50 of 13.7 ppm for A. stephensi and 14.7 ppm for A. albopictus. The predation efficiency of Gambusia affinis against A. stephensi and A. albopictus III instar larvae was 86.2 and 81.7 %, respectively. In AgNP-contaminated environments, predation was 93.7 and 88.6 %, respectively. This research demonstrates that M. elengi-synthesized AgNP may be employed at ultra-low doses to reduce larval populations of malaria and arbovirus vectors, without detrimental effects on predation rates of mosquito natural enemies, such as larvivorous fishes.

Each year, mosquito-borne diseases infect nearly 700 million people, resulting to more than 1 million deaths. In this study, we evaluated the larvicidal, pupicidal, and smoke toxicity of Senna occidentalis and Ocimum basilicum leaf extracts against the malaria vector Anopheles stephensi. Furthermore, the antiplasmodial activity of plant extracts was evaluated against chloroquine (CQ)-resistant (CQ-r) and CQ-sensitive (CQ-s) strains of Plasmodium falciparum. In larvicidal and pupicidal experiments, S. occidentalis LC50 ranged from 31.05 (I instar larvae) to 75.15 ppm (pupae), and O. basilicum LC50 ranged from 29.69 (I instar larvae) to 69 ppm (pupae). Smoke toxicity experiments conducted against adults showed that S. occidentalis and O. basilicum coils evoked mortality rates comparable to the pyrethrin-based positive control (38, 52, and 42%, respectively). In antiplasmodial assays, Senna occidentalis 50% inhibitory concentration (IC50) were 48.80 μg/ml (CQ-s) and 54.28 μg/ml (CQ-r), while O. basilicum IC50 were 68.14 μg/ml (CQ-s) and 67.27 μg/ml (CQ-r). Overall, these botanicals could be considered as potential sources of metabolites to build newer and safer malaria control tools.

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 synthesized of natural products for vector control have been a priority in this area. In the present study, silver nanoparticles (Ag NPs) were green-synthesized using a floral extract of Chrysanthemum indicum screened for larvicidal and pupicidal activity against the first to fourth instar larvae and pupae of the malaria vector Anopheles stephensi mosquitoes. The synthesized Ag NPs were characterized by using UV-vis absorption, X-ray diffraction, transmission electron microscopy, and energy-dispersive X-ray spectroscopy techniques. The textures of the yielded Ag NPs were found to be spherical and polydispersed with a mean size in the range of 25-59 nm. Larvae and pupae were exposed to various concentrations of aqueous extract of C. indicum and synthesized Ag NPs for 24 h, and the maximum mortality was observed from the synthesized Ag NPs against the vector A. stephensi (LC50 = 5.07, 10.35, 14.19, 22.81, and 35.05 ppm; LC90 = 29.18, 47.15, 65.53, 87.96, and 115.05 ppm). These results suggest that the synthesized Ag NPs have the potential to be used as an ideal eco-friendly approach for the control of A. stephensi. Additionally, this study provides the larvicidal and pupicidal properties of green-synthesized Ag NPs with the floral extract of C. indicum against vector mosquito species from the geographical location of India.

Objective: To explore the larvicidal activity of Catharanthus roseus (C. roseus) leaf extract and Bacillus thuringiensis (B. thuringiensis) against the malarial vector Anopheles stephensi (An. stephensi), when being used alone or together., Methods: The larvicidal activity was assayed at various concentrations under the laboratory and field conditions. The LC50 and LC90 values of the C. roseus leaf extract were determined by probit analysis., Results: The plant extract showed larvicidal effects after 24 h of exposure; however, the highest larval mortality was found in the petroleum ether extract of C. roseus against the first to fourth instars larvae with LC50=3.34, 4.48, 5.90 and 8.17 g/L, respectively; B. thuringiensis against the first to fourth instars larvae with LC50=1.72, 1.93, 2.17 and 2.42 g/L, respectively; and the combined treatment with LC50=2.18, 2.41, 2.76 and 3.22 g/L, respectively. No mortality was observed in the control., Conclusions: The petroleum ether extract of C. roseus extract and B. thuringiensis have potential to be used as ideal eco-friendly agents for the control of An. stephensi in vector control programs. The combined treatment with this plant crude extract and bacterial toxin has better larvicidal efficacy against An. stephensi., (Copyright © 2013 Hainan Medical College. Published by Elsevier B.V. All rights reserved.)

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 vector mosquitoes.

Mosquitoes are insect vectors responsible for the transmission of parasitic and viral infections to millions of people worldwide, with substantial morbidity and mortality. Infections transmitted by mosquitoes include malaria, yellow fever, chikungunya, filariasis and other arboviruses. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. The adulticidal activities of crude hexane, benzene, ethyl acetate, acetone and methanol leaf extracts of Acalypha alnifolia were assayed for their toxicity against three important vector mosquitoes, viz., Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus. The adult mortality was observed after 24 h of exposure. All extracts showed moderate adulticide effects; however, the highest adult mortality was found in methanol extract were observed. The LC(50) values of A. alnifolia leaf extracts against adulticidal activity of (hexane, benzene, ethyl acetate, acetone and methanol) A. aegypti, A. stephensi and C. quinquefasciatus were the following: A. aegypti values were 371.87, 342.97, 320.17, 300.86 and 279.75 ppm; A. stephensi values were 358.35, 336.64, 306.10, 293.01 and 274.76 ppm; C. quinquefasciatus values were 383.59, 354.13, 327.74, 314.33 and 291.71 ppm. The results of the repellent activity of hexane, benzene, ethyl acetate, acetone and methanol extract of A. alnifolia plant at three different concentrations of 1.0, 3.0, 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. Mean percent hatchability of the ovicidal activity was observed 48 h post-treatment. The percent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. Mortality of 100 % with methanol extract of A. alnifolia was exerted at 125 and 300 ppm. The larval density was decreased after the treatment of plant extracts at the breeding sites (water bodies system) of vector mosquitoes, and hence, these plant extracts are suitable alternatives of synthetic insecticides for mosquito vector management.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 mosquitoes. This study provides first report on the mosquito ovicidal, repellent and adulticidal activities of these plant extracts against mosquito vector species from India.

The present study evaluated the Orthosiphon thymiflorus leaf extract and the bacterial insecticide spinosad, testing the first to fourth instars larvae and pupae of two important vector mosquitoes, viz., Aedes aegypti, Anopheles stephensi. The fresh leaves of O. thymiflorus were washed thoroughly in tap water and shade-dried at room temperature (28 ± 2 °C) for 5 to 8 days. The air-dried materials were powdered separately using a commercial electrical blender. From the plants, 500 g powder was macerated with 1.5 L organic solvents of petroleum ether sequentially for a period of 72 h each and then filtered. The larval and pupal mortality was observed after 24 h of exposure; no mortality was observed in the control group. The first- to fourth-instar larvae and pupae of A. stephensi had values of LC(50) = 309.16, 337.58, 390.42, 429.68, and 513.34 ppm, and A. aegypti had values of LC(50) = 334.78, 366.45, 422.97, 467.94, and 54.02 ppm, respectively. Spinosad against the A. stephensi had values of LC(50) = 384.19, 433.39, 479.17, 519.79, and 572.63 ppm, and A. aegypti had values of LC(50) = 210.68, 241.20, 264.93, 283.27, and 305.85 ppm, respectively. Moreover, in combined treatment, the A. stephensi had values of LC(50) = 202.36, 224.76, 250.84, 288.05, and 324.05 ppm, and A. aegypti had values of LC(50) = 217.70, 246.04, 275.36, 315.29, and 353.80 ppm, respectively. Results showed that the leaf extract of O. thymiflorus and bacterial insecticide spinosad are promising as a good larvicidal and pupicidal against dengue vector, A. aegypti and malarial vector, A. stephensi. This is an ideal eco-friendly approach for the control of target species of vector control programs.

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. The aim of the present study, to evaluate the larvicidal, pupicidal, repellent, and adulticidal activities of methanol crude extract of Artemisia nilagirica were assayed for their toxicity against two important vector mosquitoes, viz., Anopheles stephensi and Aedes aegypti (Diptera: Culicidae). The fresh leaves of A. nilagirica were washed thoroughly in tap water and shade dried at room temperature (28 ± 2 °C) for 5-8 days. The air-dried materials were powdered separately using commercial electrical blender. From the plants, 500 g powdered was macerated with 1.5 L organic solvents of methanol sequentially for a period of 72 h each and filtered. The larval and pupal mortality was observed after 24 h of exposure; no mortality was observed in the control group. The first- to fourth-instar larvae and pupae of A. stephensi had values of LC(50) = 272.50, 311.40, 361.51, 442.51, and 477.23 ppm, and the LC(90) = 590.07, 688.81, 789.34, 901.59, and 959.30 ppm; the A. aegypti had values of LC(50) = 300.84, 338.79, 394.69, 470.74, and 542.11 ppm, and the LC(90) = 646.67, 726.07, 805.49, 892.01, and 991.29 ppm, respectively. The results of the repellent activity of plant extract of A. nilagirica plants at five different concentrations of 50, 150, 250, 350, and 450 ppm were applied on skin of fore arm in man and exposed against adult female mosquitoes. In this observation, the plant crude extract 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. The adult mortality was found in methanol extract of A. nilagirica, with the LC(50) and LC(90) values of 205.78 and 459.51 ppm for A. stephensi, and 242.52 and 523.73 ppm for A. aegypti, respectively. This result suggests that the leaf extract have the potential to be used as an ideal eco-friendly approach for the control of vector mosquito as target species.

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 mosquitoes. This is the first report on mosquito adulticidal and repellent activities of the reported C. tora against mosquito vectors from Southern India.

The bio-efficacy of Aloe vera leaf extract and bacterial insecticide, Bacillus sphaericus larvicidal activity was assessed against the first to fourth instars larvae of Aedes aegypti, under the laboratory conditions. The plant material was shade dried at room temperature and powdered coarsely. A. vera and B. sphaericus show varied degrees of larvicidal activity against various instars larvae of A. aegypti. The LC50 of A. vera against the first to fourth instars larvae were 162.74, 201.43, 253.30 and 300.05 ppm and the LC90 442.98, 518.86, 563.18 and 612.96 ppm, respectively. B. sphaericus against the first to fourth instars larvae the LC50 values were 68.21, 79.13, 93.48, and 107.05 ppm and the LC90 values 149.15, 164.67, 183.84, and 201.09 ppm, respectively. However, the combined treatment of A. vera + B. sphaericus (1:2) material shows highest larvicidal activity of the LC50 values 54.80, 63.11, 74.66 and 95.10 ppm; The LC90 values of 145.29, 160.14, 179.74 and 209.98 ppm, against A. aegypti in all the tested concentrations than the individuals and clearly established that there is a substantial amount of synergist act. The present investigation clearly exhibits that both A. vera and B. sphaericus materials could serve as a potential larvicidal agent. Since, A. aegypti is a container breeder vector mosquito this user and eco-friendly and low-cost vector control strategy could be a viable solution to the existing dengue disease burden. Therefore, this study provides first report on the mosquito larvicidal activity the combined effect of A. vera leaf extract and B. sphaericus against as target species of A. aegypti.

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 species of mosquito vectors of this plant extracts from India.

Mosquitoes are the carriers of severe and well-known illnesses such as malaria, arboviral encephalitis, dengue fever, chikunguniya fever, West Nile virus and yellow fever. These diseases produce significant morbidity and mortality in humans and livestock around the world. The present study explored the effects of orange peel ethanol extract of Citrus sinensis on larvicidal, pupicidal, repellent and adulticidal activity against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus. The orange peel material was shade dried at room temperature and powdered coarsely. From orange peel, 300 g powdered was macerated with 1 L of ethanol sequentially for a period of 72 h each and filtered. The yields of the orange peel ethanol crude extract of C. sinensis 13.86 g, respectively. The extracts were concentrated at reduced temperature on a rotary vacuum evaporator and stored at a temperature of 4 °C. The larvicidal, pupicidal and adult mortality was observed after 24 h of exposure; no mortality was observed in the control group. For C. sinensis, the median lethal concentration values (LC(50)) observed for the larvicidal and pupicidal activities against mosquito vector species A. stephensi first to fourth larval instars and pupae were 182.24, 227.93, 291.69, 398.00 and 490.84 ppm; A. aegypti values were 92.27, 106.60, 204.87, 264.26, 342.45, 436.93 and 497.41 ppm; and C. quinquefasciatus values were 244.70, 324.04, 385.32, 452.78 and 530.97 ppm, respectively. The results of maximum repellent activity were observed at 450 ppm in ethanol extracts of C. sinensis and the mean complete protection time ranged from 150 to 180 min was tested. The ethanol extract of C. sinensis showed 100% repellency in 150 min and showed complete protection in 90 min at 350 ppm against A. stephensi, A. aegypti and C. quinquefasciatus, respectively. The adult mortality was found in ethanol extract of C. sinensis with the LC(50) and LC(90) values of 272.19 and 457.14 ppm, A. stephensi; 289.62 and 494.88 ppm, A. aegypti; and 320.38 and 524.57 ppm, respectively. These results suggest that the orange peel extracts of C. sinensis have the potential to be used as an ideal eco-friendly approach for the control of the vector control programmes.

Sphaeranthus indicus, Cleistanthus collinus and Murraya koenigii leaf extracts were tested against the third instar larvae of Culex quinquefasciatus. The plant material was shade dried at room temperature and powdered coarsely. From each plant, 500 g powder was macerated with 1.5 L of hexane, chloroform and ethyl acetate sequentially for a period of 72 h each and filtered. The yield of the S. indicus, C. collinus and M. koenigii crude extracts by hexane, chloroform and ethyl acetate was 9.16, 11.71 and 10.83 g for S. indicus; 8.17, 10.69 and 9.85 g for C. collinus; and 10.11, 11.92 and 9.87 g for M. koenigii, respectively. The extracts were concentrated at reduced temperature on a rotary vacuum evaporator and stored at a temperature of 4°C. The S. indicus, C. collinus and M. koenigii leaf extracts at 250, 500, 750 and 1,000 ppm caused a significant mortality of C. quinquefasciatus. The LC(50) and LC(90) values of S. indicus, C. collinus and M. koenigii against third instar larvae at 24, 48 and 72 h (hexane, chloroform and ethyl acetate) were the following: S. indicus LC(50) values were 544.93, 377.86 and 274.79 ppm and LC(90) values were 1,325.32, 1,572.55 and 1,081.29 ppm at 24 h; C. collinus LC(50) values were 375.34, 318.29 and 226.10 ppm and LC(90) values were 699.65, 1,577.62 and 1,024.92 ppm at 24 h; and M. koenigii LC(50) values were 963.53, 924.85 and 857.62 ppm and LC(90) values were 1,665.12, 1,624.68 and 1,564.37 ppm at 24 h, respectively. However, the highest larval mortality was observed in C. collinus followed by S. indicus and M. koenigii of various concentrations at 24, 48 and 72 h. The study proved that S. indicus, C. collinus and M. koenigii leaf extracts had larvicidal property against species of C. quinquefasciatus. This is an ideal ecofriendly approach for the control of vector control programmes.

Calotropis gigantea leaf extract and Bacillus thuringiensis were tested first to fourth-instar larvae and pupae of Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus. The medicinal plants were collected from the area around Bharathiar University, Coimbatore, India. Calotropis gigantea leaf was washed with tap water and shade-dried at room temperature. An electrical blender powdered the dried plant materials (leaves). The powder 500 g of the leaf was extracted with 1.5 L of organic solvents of methanol for 8 h using a Soxhlet apparatus and filtered. The crude leaf extracts were evaporated to dryness in a rotary vacuum evaporator. The plant extract showed larvicidal and pupicidal effects after 24 h of exposure; no mortality was observed in the control group. For Calotropis gigantea, the median lethal concentration values (LC(50)) observed for the larvicidal and pupicidal activities against mosquito vector species Anopheles stephensi I to IV larval instars and pupae were 73.77, 89.64, 121.69, 155.49, and 213.79 ppm; Aedes aegypti values were 92.27, 106.60, 136.48, 164.01, and 202.56 ppm; and Culex quinquefasciatus values were 104.66, 127.71, 173.75, 251.65, and 314.70 ppm, respectively. For B. thuringiensis, the LC(50) values of I to IV larval instars and pupae of Anopheles stephensi were 37.24, 45.41, 57.82, 80.09, and 98.34 ppm; Aedes aegypti values were 42.38, 51.90, 71.02, 96.17, and 121.59 ppm; and Culex quinquefasciatus values were 55.85, 68.07, 94.11, 113.35, and 133.87 ppm, respectively. The study proved that the methanol leaf extract of Calotropis gigantea and bacterial insecticide B. thuringiensis has mosquitocidal property and was evaluated as target species of mosquito vectors. This is an ideal ecofriendly approach for the control of vector control programs.

The present study was carried out on Solanum xanthocarpum fruit extract and copepods Mesocyclops thermocyclopoides, which were assessed for the control of dengue vector, Aedes aegypti, under laboratory conditions. The medicinal plants were collected from the outskirts of Bharathiar University, Coimbatore, Tamil Nadu, India. The shade-dried fruit materials were extracted by employing the Soxhlet apparatus with methanol (organic solvent) 8 h and the extracts were filtered through a Buchner funnel with Whatman number 1 filter paper. The fruit extracts were concentrated at reduced temperature on a rotary vacuum evaporator and stored at a temperature of 4°C. S. xanthocarpum fruit extract (SXFE) at 100, 150, 200, 250, and 300 ppm caused significant mortality of Ae. aegypti. The LC(50) and LC(90) of S. xanthocarpum against the first to fourth instar larvae and pupae were 170.91, 195.07, 221.45, 253.18, and 279.52 ppm and 320.62, 366.48, 410.20, 435.16, and 462.10 ppm, respectively. A study was conducted to test whether the predatory efficiency of copepods on first instars changed in the presence of SXFE. The percentage of predatory efficiency of copepod was 6.5 % in treatments without SFXE and the percentage of predatory efficiency increased up to 8.7 % when copepods were combined with SFXE. This increase in predation efficiency may be caused by detrimental effects of the SFXE active principle compound (solanocarpine and solanocarpidine) on the mosquito larvae. Repeated application of fruit extract of S. xanthocarpum does not cause changes in copepod populations because fruit extract is highly degradable in the environment. Therefore, the present investigation clearly exhibits that the fruit extract of S. xanthocarpum and copepod M. thermocyclopoides could serve as a potential of highest mortality rate against the mosquito larvae under laboratory conditions. This is a new eco-friendly approach for the control of Ae. aegypti mosquito as target species. Therefore, this study provides the first report on the combined effect of mosquitocidal activity of this fruit extract and copepods of M. thermocyclopoides against dengue vector Ae. aegypti from India.

The bio-efficacy of Solanum xanthocarpum leaf extract and bacterial insecticide, Bacillus thuringiensis, were assessed against the first to fourth instar larvae and pupae of Culex quinquefasciatus, under the laboratory conditions. The medicinal plants were collected from the outskirt Bharathiar University, Coimbatore, Tamil Nadu, India. The shade dried plant materials were extracted by employing the Soxhlet apparatus with ethanol (organic solvent) for 8 h and filtered. The extracts were concentrated at reduced temperature on a rotary evaporator and stored at a temperature of 4°C. Both S. xanthocarpum and B. thuringiensis show varied degree of larvicidal and pupicidal activity against various stages of C. quinquefasciatus. The LC(50) and LC(90) of S. xanthocarpum against the first to fourth instar larvae and pupae were 155.29, 198.32, 271.12, 377.44, and 448.41 ppm and 687.14, 913.10, 1,011.89, 1,058.85, and 1,141.65 ppm, respectively. On the other hand, the LC(50) values of B. thuringiensis against the first to fourth instar larvae and pupae were 133.88, 157.14, 179.44, 206.80, and 240.74 ppm; the LC(90) values were 321.04, 346.89, 388.86, 430.95, and 492.70 ppm, respectively. However, the combined treatment of S. xanthocarpum + B. thuringiensis (1:2) material shows highest larvicidal and pupicidal activity of the LC(50) values 126.81, 137.62, 169.14, 238.27, and 316.02 ppm and the LC(90) values 476.36, 613.49, 705.29, 887.85, and 1,041.73 ppm against C. quinquefasciatus in all the tested concentrations than the individuals and clearly established that there is a substantial amount of synergist act. Therefore, the present investigation clearly exhibit that both S. xanthocarpum and B. thuringiensis materials could serve as a potential of highest mortality rate against the mosquito larvae laboratory as well as the field conditions. Since C. quinquefasciatus is a ditch breeder vector mosquito, this is a user and eco-friendly biopesticide for the control of mosquito vector management program.

The present study explored the effects of Jatropha curcas, Hyptis suaveolens, Abutilon indicum, and Leucas aspera tested against third instar larvae of filarial vector, Culex quinquefasciatus. The dried plant materials were powdered by an electrical blender. From each sample, 500 g powder was macerated with 1.5 L of hexane, chloroform, ethyl acetate, and methanol 8h, using Soxhlet apparatus, and filtered. The extracts were concentrated at reduced temperature on a rotary evaporator and stored at a temperature of 4°C. The yield of crude extract was 11.4, 12.2, 10.6, and 13.5 g in hexane, chloroform, ethyl acetate, and methanol, respectively. The hexane, chloroform, ethyl acetate, and methanol extract of J. curcas with LC(50) values of 230.32, 212.85, 192.07, and 113.23 ppm; H. suaveolens with LC(50) values of 213.09, 217.64, 167.59, and 86.93 ppm; A. indicum with LC(50) values of 204.18, 155.53, 166.32, and 111.58 ppm; and L. aspera with LC(50) values of 152.18, 118.29, 111.43, and 107.73 ppm, respectively, against third instar larvae of C. quinquefasciatus. The larval mortality was observed after 24 h of exposure. Maximum larvicidal activity was observed in the methanolic extract followed by ethyl acetate, chloroform, and hexane extract. No mortality was observed in the control. The observed mortality were statistically significant at P < 0.05 level. L. aspera showed the highest mortality rate against the mosquito larvae in laboratory and field. The larval density was decreased after the treatment of plant extracts at the breeding sites (sewage water), and hence, these plant extracts of the suitable alternatives of synthetic insecticides for the mosquito vector management. The present results suggest that the medicinal plants extract was an excellent potential for controlling filarial vector, C. quinquefasciatus.

The present study was to establish of Acalypha alnifolia leaf extract and microbial insecticide, Metarizhium anisopliae on larvicidal and pupicidal properties of against the malaria fever mosquito, Anopheles stephensi. The leaf extract showed larvicidal and pupicidal effects after 24 h of exposure; however, the highest larval and pupal mortality was found in the leaf extract of ethanol A. alnifolia against the 1st to 4th instar larvae and pupae of values LC(50) value of 1st instar was 5.388%, 2nd instar was 6.233%, 3rd instar was 6.884%, 4th instar was 8.594%, and pupae was 10.073%, respectively, and microbial insecticide, M. anisopliae against the 1st to 4th instar larvae and pupae of values LC(50) value of 1st instar was 7.917%, 2nd instar was 10.734%, 3rd instar was 17.624%, 4th instar was 26.590%, and pupae was 37.908%, respectively. Moreover, combined treatment of values of LC(50) value of 1st instar was 3.557%, 2nd instar was 4.373%, 3rd instar was 5.559%, 4th instar was 7.223%, and pupae was 8.542%, respectively. No mortality was observed in the control. The results that the leaves extract of A. alnifolia and microbial insecticide, M. anisopliae is promising as good larvicidal and pupicidal properties of against malaria fever mosquito, A. stephensi. This is an ideal eco-friendly approach for the control of malarial vector, A. stephensi as a vector control programs. Therefore, this study provides first report on the combined effect of mosquitocidal efficacy of this plant extract and fungal pathogen of M. anisopliae against A. stephensi from Southern India.

Ethanolic extracts of Cynodon dactylon, Aloe vera, Hemidesmus indicus and Coleus amboinicus were tested for their toxicity effect on the third-instar larvae of Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti. The leaves of C. dactylon, A. vera, H. indicus and C. amboinicus were collected from natural habitats (forests) in Western Ghats, Tamil Nadu, India. A total of 250 g of fresh, mature leaves were rinsed with distilled water and dried in shade. The dried leaves were put in Soxhlet apparatus and extract prepared using 100% ethanol for 72 h at 30-40°C. Dried residues were obtained from 100 g of extract evaporated to dryness in rotary vacuum evaporator. Larvicidal properties of ethanolic leaf extracts showed that the extracts are effective as mosquito control agents. The larval mortality was observed after 24 h exposure. No mortality was observed in the control. The median lethal concentration (LC(50)) values observed for the larvicidal activities are 0.44%, 0.51%, 0.59% and 0.68% for extracts of C. dactylon, A. vera, H. indicus and C. amboinicus, respectively. The observed mortality were statistically significant at P < 0.05 level. C. dactylon showed the highest mortality rate against the three species of mosquito larvae in laboratory and field. The selected plants were shown to exhibit water purification properties. Water quality parameters such as turbidity, pH and water clarity were analyzed in the water samples (pre-treatment and post-treatment of plant extracts) taken from the different breeding sites of mosquitoes. Water colour, turbidity and pH were reduced significantly after treatment with C. dactylon (13 HU, 31.5 mg/l and 6.9), H. indicus (13.8 HU, 33 mg/l and 7.1), A. vera (16 HU, 33.8 mg/l and 7.4) and C. amboinicus (21 HU, 35 mg/l and 7.5) extracts. The study proved that the extracts of C. dactylon, A. vera, H. indicus and C. amboinicus have both mosquitocidal and water sedimentation properties.

The leaf extract of Acalypha alnifolia with different solvents - hexane, chloroform, ethyl acetate, acetone and methanol - were tested for larvicidal activity against three important mosquitoes such as malarial vector, Anopheles stephensi, dengue vector, Aedes aegypti and Bancroftian filariasis vector, Culex quinquefasciatus. The medicinal plants were collected from the area around Kallar Hills near the Western Ghats, Coimbatore, India. A. alnifolia plant was washed with tap water and shade dried at room temperature. The dried leaves were powdered mechanically using commercial electrical stainless steel blender. The powder 800 g of the leaf material was extract with 2.5 litre of various each organic solvents such as hexane, chloroform, ethyl acetate, acetone, methanol for 8 h using Soxhlet apparatus, and filtered. The crude plant extracts were evaporated to dryness in a rotary vacuum evaporator. The yield of extracts was hexane (8.64 g), chloroform (10.74 g), ethyl acetate (9.14 g), acetone (10.02 g), and methanol (11.43 g). One gram of the each plant residue was dissolved separately in 100 ml of acetone (stock solution) from which different concentrations, i.e., 50, 150, 250, 350 and 450 ppm, was prepared. The hexane, chloroform, ethyl acetate, acetone was 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 early fourth-instar larvae of A. stephensi had values of LC(50) = 197.37, 178.75, 164.34, 149.90 and 125.73 ppm and LC(90) = 477.60, 459.21, 435.07, 416.20 and 395.50 ppm, respectively. The A. aegypti had values of LC(50) = 202.15, 182.58, 160.35, 146.07 and 128.55 ppm and LC(90) = 476.57, 460.83, 440.78, 415.38 and 381.67 ppm, respectively. The C. quinquefasciatus had values of LC(50) = 198.79, 172.48, 151.06, 140.69 and 127.98 ppm and LC(90) = 458.73, 430.66, 418.78, 408.83 and 386.26 ppm, respectively. The results of the leaf extract of A. alnifloia are promising as good larvicidal activity against the mosquito vector, A. stephensi, A. aegypti, C. quinquefasciatus. Therefore, this study provides first report on the larvicidal activities against three species of mosquito vectors of this plant extracts from Southern India.

The present study was carried out to establish the properties of Carica papaya leaf extract and bacterial insecticide, spinosad on larvicidal and pupicidal activity against the chikungunya vector, Aedes aegypti. The medicinal plants were collected from the area around Bharathiar University, Coimbatore, India. C. papaya leaf was washed with tap water and shade-dried at room temperature. An electrical blender powdered the dried plant materials (leaves). The powder (500 g) of the leaf was extracted with 1.5 l of organic solvents of methanol for 8 h using a Soxhlet apparatus and then filtered. The crude leaf extracts were evaporated to dryness in a rotary vacuum evaporator. The plant extract showed larvicidal and pupicidal effects after 24 h of exposure; however, the highest larval and pupal mortality was found in the leaf extract of methanol C. papaya against the first- to fourth-instar larvae and pupae of values LC(50) = I instar was 51.76 ppm, II instar was 61.87 ppm, III instar was 74.07 ppm, and IV instar was 82.18 ppm, and pupae was 440.65 ppm, respectively, and bacterial insecticide, spinosad against the first to fourth instar larvae and pupae of values LC(50) = I instar was 51.76 ppm, II instar was 61.87 ppm, III instar was 74.07 ppm, and IV instar was 82.18 ppm, and pupae was 93.44 ppm, respectively. Moreover, combined treatment of values of LC(50) = I instar was 55.77 ppm, II instar was 65.77 ppm, III instar was 76.36 ppm, and IV instar was 92.78 ppm, and pupae was 107.62 ppm, respectively. No mortality was observed in the control. The results that the leaves extract of C. papaya and bacterial insecticide, Spinosad is promising as good larvicidal and pupicidal properties of against chikungunya vector, A. aegypti. This is an ideal eco-friendly approach for the control of chikungunya vector, A. aegypti as target species of vector control programs.

The efficacy of whole plant extracts of Leucas aspera and Bacillus sphaericus has been proven against larvicidal and pupicidal activities of the malarial vector, Anopheles stephensi. The present study investigated the larvicidal and pupicidal activity against the first to fourth instar lavae and pupae of the laboratory-reared mosquitoes, A. stephensi. The medicinal plants were collected from the area around Maruthamalai hills, Coimbatore, Tamil Nadu, India. L. aspera whole plant was washed with tap water and shade dried at room temperature. The dried plant materials were powdered by an electric blender. From the powder, 100 g of the plant materials was extracted with 300 ml of organic solvents of ethanol for 8 h using a Soxhlet apparatus. The extracts were filtered through a Buchner funnel with Whatman number 1 filter paper. The crude plant extracts were evaporated to dryness in a rotary vacuum evaporator. The plant extract showed larvicidal and pupicidal effects after 24 h of exposure. All larval instars and pupae have considerably moderate mortality; however, the highest larval mortality was the ethanolic extract of whole plant L. aspera against the first to fourth instar larvae and pupae values of LC(50) = I instar was 9.695%, II instar was 10.272%, III instar was 10.823%, and IV instar was 11.303%, and pupae was 12.732%. B. spaericus against the first to fouth instar larvae and pupae had the following values: I instar was 0.051%, II instar was 0.057%, III instar was 0.062%, IV instar was 0.066%, and for the pupae was 0.073%. No mortality was observed in the control. The present results suggest that the ethanolic extracts of L. aspera and B. sphaericus provided an excellent potential for controlling of malarial vector, A. stephensi.

The present study explored the effects of Jatropha curcas leaf extract and Bacillus thuringiensis israelensis larvicidal activity against the lymphatic filarial vector, Culex quinquefasciatus. Wights were selected for investigating the larvicidal potential against the first to fourth instar larvae of the laboratory-reared mosquito species, C. quinquefasciatus Say, in which the major lymphatic filariasis was used. The medicinal plants were collected from the area around Bharathiar University, Coimbatore. The dried plant materials were powdered by an electric blender. From the powder, 100 g of the plant materials was extracted with 300 ml of organic solvents of methanol for 8 h, using a Soxhlet apparatus, and filtered. The crude plant extracts were evaporated to dryness in a rotary vacuum evaporator. The plant extract showed larvicidal effects after 24 h of exposure; however, the highest larval mortality was found in the leaf extract of methanol J. curcas against the first to fourth instar larvae of values LC(50) = 1.200%, 1.290%, 1.358%, and 1.448% and LC(90) = 2.094%, 2.323%, 2.444%, and 2.544% and B. thuringiensis israelensis against the first to fourth instar larvae of values LC(50) = 9.332%, 9.832%, 10.212%, 10.622% and LC(90) = 15.225%, 15.508%, 15.887%, and 15.986% larvae of C. quinquefasciatus, respectively. No mortality was observed in the control. These results suggest methanol extracts of J. curcas and B. thuringiensis israelensis have potential to be used as an ideal eco-friendly approach for the control of the major lymphatic filarial vector, C. quinquefasciatus.