Leaf and seed extracts of Abutilon indicum against the fourth instar larvae of Culex quinquefasciatus

AbstractFourth instar larvae of a new strain of Culex quinquefasciatus Say from Tanzania (TANGA) were tested for insecticide resistance. Initially, the resistance ratio (RR) to chlorpyrifos was 41.8, to temephos 30.8, to propoxur 3.7. After 2–3 years of laboratory culture, resistance to chlorpyrifos and propoxur had declined (chlorpyrifos 5.7, 3.8; propoxur 1.9, permethrin 1.9). Significant synergism was found between s, s, s-tributyl trithiophosphate (DEF) and chlorphyrifos, reducing the RR from 8.0 to 2.5. Synergism between piperonyl butoxide and permethrin was less than in a susceptible control strain. Twelve esterase isozymes of different relative mobilities (Rm) on polyacrylamide gel electrophoresis were identified, ten of which remained when the strain was reinvestigated two years (approximately 32 generations) later. Null activity for all but one of these bands was observed in some larvae. Four esterase bands (Rm 0.25, 0.27, 0.31, 0.34, designated A2, A3, B2, B3) showed polymorphism in activity, with very intense bands in some larvae. The mean frequency of bands with activity greater than standard, declined as organophosphorus (OP) resistance declined, but resistance was unconnected with the frequency of nulls at these positions. In mass larval assays of in vitro sensitivity of acetylcholinesterase (AChE) to propoxur, the I50 exceeded 10x10−4M, compared with 0.1x10−4M in a reverted resistant strain (RANGOON). Single larvel assays revealed heterogeneity, which was interpreted on the basis of an AChE resistance allele (AceR) with a frequency of 0.23.

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Comparative Evaluation of the Larvicidal Properties of Methanol Extracts and Fractions of Ocimum gratissimum L. and Ocimum basilicum L. Leaves (Lamiaceae) on the Fourth Instar Larvae of Culex quinquefasciatus L. and Control of Filariasis

Journal of Complementary and Alternative Medical Research ◽

10.9734/jocamr/2020/v11i330187 ◽

2020 ◽

pp. 24-31

Author(s):

Romanus A. Umoh ◽

Imoh I. Johnny ◽

Anwanabasi E. Udoh ◽

Akwaowoh A. Elijah ◽

Omodot T. Umoh ◽

...

Keyword(s):

Culex Quinquefasciatus ◽

Linear Regression Analysis ◽

Positive Control ◽

Ocimum Basilicum ◽

Fourth Instar ◽

Botanical Insecticides ◽

Methanol Extracts ◽

Ocimum Gratissimum ◽

Crude Extracts ◽

And Control

Background: Botanical insecticides may serve as suitable alternatives to synthetic insecticides because they contain bioactive chemicals. They are relatively safe, biodegradable and readily available in many areas of the world. Objective: The aim of this study is to comparatively evaluate the larvicidal properties of methanol extracts and fractions of Ocimum gratissimum and Ocimum basilicum leaves on fourth instar larvae of Culex quinquefasciatus, the vector of filariasis. Methods: The plants were identified, collected, air-dried and pulverized. The powdered leaves were macerated in 100% redistilled methanol for 72 hours, filtered and concentrated to thick extracts. After the preliminary work was done as activity-guided process, the crude extracts were partitioned into different solvents and again concentrated to thick fractions. The percentage yields were calculated and recorded. The larvae were collected from a location at Ewet Housing Estate, Uyo, Akwa Ibom State. Toxicity was evaluated by exposing fourth instar larvae of Culex quinquefasciatus to a concentration range of 0.0625 to 1.000mg/mL of the methanol crude extracts and fractions. The larval mortalities were recorded after 24 hours of exposure and LC50 values were determined using the non-linear regression analysis of a statistical package graph pad prism®. Results: The results of percentage mortalities of methanol crude extracts ranged from 2.5±0.50 to 67.50±1.05% for O. gratissimum and 2.5±0.50 to 100±0.00% for O. basilicum with their LC50 of 0.79mg/mL and 0.18mg/mL respectively. The solvent partitioned fractions also showed that the percentage mortalities of n-hexane and chloroform of O. gratissimum ranged from 5±1.00% to 100±0.00% and 17.5±1.5% to 97.5±0.5% with their LC50 of 0.29mg/mL and 0.32 mg/mL respectively, while those of O. basilicum ranged from 0.25±0.5% to 100±0.00% for n-hexane and 7.5±0.5% to 92.5±1.5% for chloroform fractions with their LC50 of 0.42mg/mL and 0.39 mg/mL compared to that of Nicotine (positive control) with LC50 of 0.01mg/mL with a percentage mortality range of 10±1.00 to 100±0.00%. Conclusion: O. basilicum leaf methanol crude extract was more than four times active than that of O. gratissimum, but n-hexane and chloroform solvent partitioned fractions of O. gratissimum were more active than those of O. basilicum considering their percentage mortalities and LC50. Hence, both methanol crude extracts of O. basilicum and n-hexane fraction of O. gratissimum have greater potentials as larvicides which can also be used in the control of C. quinquefasciatus larvae.

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Efficacy of Seed Extracts of Cuscuta chinensis and Asparagus setaceus as Assumed Synergist against Larval Immatures of Culex quinquefasciatus

Journal of Mosquito Research ◽

10.5376/jmr.2020.10.0001 ◽

2020 ◽

Author(s):

Chakraborty Sumanta ◽

Goutam Chandra

Keyword(s):

Culex Quinquefasciatus ◽

Cuscuta Chinensis ◽

Seed Extracts

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Effectiveness of Three Fruit Seed Extracts as Larvicide against Three Major Mosquito Vectors Aedes aegypti Linnaeus, Culex quinquefasciatus Say and Anopheles gambiae Giles (Diptera: Culicidae)

International Journal of TROPICAL DISEASE & Health ◽

10.9734/ijtdh/2020/v41i2330415 ◽

2020 ◽

pp. 16-29

Author(s):

Lame Younoussa ◽

Kary Mallam Oumarou ◽

Theodora Kopa Kowa ◽

Serge Eteme Enama ◽

Gabriel Agbor Agbor ◽

...

Keyword(s):

Aedes Aegypti ◽

Anopheles Gambiae ◽

Culex Quinquefasciatus ◽

Tap Water ◽

Mosquito Species ◽

Mangifera Indica ◽

Larval Mortality ◽

Persea Americana ◽

Plant Seed ◽

Seed Extracts

The CH2Cl2-MeOH (30:70 v/v) extracts of the seeds of Mangifera indica (Mango), Persea americana (Avocado) and Dacryodes edulis (African plum) were evaluated for potential mosquito larvicidal activity against 3rd and 4th instar larvae of Aedes aegypti, Culex quinquefasciatus and Anopheles gambiae. Extracts were diluted with 1 mL of methanol and concentrations ranging from 1000 to 125 mg/L in 4 replicates each, were prepared in the volume of 100 mL in the plastic cups (250 mL). A volume of 1 mL of methanol added to 99 mL of tap water was prepared as negative control and Bi-one (1000 mg/L) constituted a positive control. In each test solution, 25 larvae of each mosquito species were separately transferred and larval mortality was recorded after 24 h post-treatment. As results, the three plant seed extracts applied at 1000 mg/L caused for at least 79% mortality of each mosquito species larvae assessed. The seed extract of P. americana (LC50 of 98.31, 129.24 and 136.26 mg/L, respectively against An. gambiae, Ae. aegypti and Cx. quiquefasciatus larvae) was the most potent followed by D. edulis (LC50 of 176.87 mg/L for An. gambiae, 198.68 mg/L for Ae. aegypti and 201.70 mg/L for Cx. quinquefasciatus) and M. indica (LC50 of 258.98 mg/L for An. gambiae, 297.35 mg/L for Ae. aegypti and 435.45 mg/L for Cx. quinquefasciatus). Globally, all the seed extracts were more toxic against An. gambiae larvae compared to other mosquito species and need further exploration for the development of a new botanical larvicide to reduce mosquito densities.

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Larvicidal efficacy of ethanol leaf and seed extracts of Picralima nitida in the control of Culex quinquefasciatus and Aedes aegypti

Nigerian Journal of Parasitology ◽

10.4314/njpar.v37i2.10 ◽

2016 ◽

Vol 37 (2) ◽

pp. 174

Author(s):

P.M.E. Ubulom ◽

U.S. Ekong

Keyword(s):

Aedes Aegypti ◽

Culex Quinquefasciatus ◽

Seed Extracts

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A 1.1-Kilobase Region Downstream of the bin Operon in Bacillus sphaericus Strain 2362 Decreases Bin Yield and Crystal Size in Strain 2297

Applied and Environmental Microbiology ◽

10.1128/aem.01444-08 ◽

2008 ◽

Vol 75 (3) ◽

pp. 878-881 ◽

Cited By ~ 5

Author(s):

Hyun-Woo Park ◽

Mujin Tang ◽

Yuko Sakano ◽

Brian A. Federici

Keyword(s):

Homologous Recombination ◽

Culex Quinquefasciatus ◽

Crystal Size ◽

Toxin Production ◽

Bacillus Sphaericus ◽

Fourth Instar ◽

Binary Toxin ◽

Size Characteristic

ABSTRACT The 2297 strain of Bacillus sphaericus produces a crystal of the Bin (binary) toxin that is approximately fourfold larger than that of strain 2362, the strain currently used in VectoLex, a commercial mosquito larvicide. Comparison of the regions downstream from the bin operon in these two strains showed that strain 2362 contained a 1.6-kb region with four orf genes not found in strain 2297. Insertion of a 1.1-kb portion of this region from strain 2362 by homologous recombination downstream from the bin operon in strain 2297 reduced Bin toxin production by 50 to 70% and toxicity to fourth-instar larvae of Culex quinquefasciatus by 68%. These results suggest that the 1.6-kb region downstream from the bin operon in B. sphaericus 2362 is responsible for the lower Bin yield and smaller crystal size characteristic of this strain.

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Recombinant Strain of Bacillus thuringiensis Producing Cyt1A, Cry11B, and the Bacillus sphaericus Binary Toxin

Applied and Environmental Microbiology ◽

10.1128/aem.69.2.1331-1334.2003 ◽

2003 ◽

Vol 69 (2) ◽

pp. 1331-1334 ◽

Cited By ~ 34

Author(s):

Hyun-Woo Park ◽

Dennis K. Bideshi ◽

Brian A. Federici

Keyword(s):

Bacillus Thuringiensis ◽

Culex Quinquefasciatus ◽

Recombinant Strain ◽

Bacillus Sphaericus ◽

Fourth Instar ◽

Lethal Concentration ◽

Binary Toxin

ABSTRACT A novel recombinant Bacillus thuringiensis subsp. israelensis strain that produces the B. sphaericus binary toxin, Cyt1Aa, and Cry11Ba is described. The toxicity of this strain (50% lethal concentration [LC50] = 1.7 ng/ml) against fourth-instar Culex quinquefasciatus was higher than that of B. thuringiensis subsp. israelensis IPS-82 (LC50 = 7.9 ng/ml) or B. sphaericus 2362 (LC50 = 12.6 ng/ml).

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Larvicidal effects of some plant seed extracts on Anopheles annularis Vander Wulp and Culex quinquefasciatus Say (Diptera: Culicidae)

Journal of Biodiversity Conservation and Bioresource Management ◽

10.3329/jbcbm.v5i2.44913 ◽

2020 ◽

Vol 5 (2) ◽

pp. 41-52

Author(s):

M Nasiruddin ◽

MA Azadi ◽

MR Chowdhury ◽

RAH Tonni

Keyword(s):

Ethyl Alcohol ◽

Culex Quinquefasciatus ◽

Mosquito Species ◽

Exposure Period ◽

Distilled Water ◽

Chi Square ◽

Plant Seed ◽

Methanol Extracts ◽

Average Temperature ◽

Seed Extracts

Larvicidal effects of distilled water, 50% ethyl alcohol, acetone and methanol extracts on seed of four plants viz. Sinapis alba (Linn.), Carica papaya (Linn.), Momordica charantia (Linn.) and Capsicum annuum (Linn.) were studied upon the mosquito larvae of Anopheles annularis Vander Wulp and Culex quinquefasciatus Say under normal laboratory conditions with average temperature and relative humidity of 31.1oC and 57.6%, respectively. Percentage mortality, probit mortality, chi-square and ANOVA values for the larvae, extracts and concentrations were calculated for 24 hours exposure period. Mortality was dose dependent. The values of LC50 of the seeds of S. alba on An. annularis at the application doses for the distilled water, 50% ethyl alcohol, acetone and methanol extracts were 3431.791, 1038.363, 1254.810 and 2269.975 ppm, respectively; for C. papaya were 804.008, 403.294, 597.165 and 573.241 ppm, respectively; for M. charantia were 10593.241, 5017.710, 5650.191 and 6075.204 ppm, respectively; and for C. annuum were 1274.968, 4637.201, 1604.852 and 1905.692 ppm, respectively. The values of LC50 of S. alba seeds on Cx. quinquefasciatus at the application doses for the distilled water, 50% ethyl alcohol, acetone and methanol extracts were 1415.311, 432.996, 569.701 and 770.250 ppm, respectively; for C. papaya were 705.599, 385.688, 341.003 and 481.067 ppm, respectively; for M. charantia were 7764.154, 4496.464, 5353.759 and 5825.031 ppm, respectively; and for C. annuum were 2173.631, 1311.538, 78.748 and 182.869 ppm, respectively. Of the four plant seed extracts, C. papaya seed extracts were the most toxic for both the mosquito species. J. Biodivers. Conserv. Bioresour. Manag. 2019, 5(2): 41-52

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Toxicological Evaluation of Novel Butenolide Pesticide Flupyradifurone Against Culex quinquefasciatus (Diptera: Culicidae) Mosquitoes

Journal of Medical Entomology ◽

10.1093/jme/tjaa118 ◽

2020 ◽

Vol 57 (6) ◽

pp. 1857-1863

Author(s):

Mohamed Ahmed Ibrahim Ahmed ◽

Christoph Franz Adam Vogel

Keyword(s):

Culex Quinquefasciatus ◽

Mosquito Control ◽

Control Strategies ◽

Synergetic Effect ◽

Fourth Instar ◽

Synergistic Action ◽

Toxicological Evaluation ◽

Control Programs ◽

Octopamine Receptor ◽

The Impact

Abstract The impact of increasing resistance of mosquitoes to conventional pesticides has led to investigate various unique tools and pest control strategies. Herein, we assessed the potency of flupyradifurone, a novel pesticide, on fourth instar larvae of Culex quinquefasciatus Say. Further, we evaluated the synergistic action of piperonyl butoxide (PBO) and the octopamine receptor agonists (OR agonists) chlordimeform (CDM) and amitraz (AMZ) on the toxicity of flupyradifurone in comparison with sulfoxaflor and nitenpyram to increase their toxicity on Cx. quinquefasciatus. Results demonstrated that flupyradifurone was the most potent pesticide followed by sulfoxaflor and nitenpyram. Further, the synergetic effect of PBO, CDM, and AMZ was significant for all selected pesticides especially flupyradifurone. However, AMZ had the most significant effect in combination with the selected pesticides followed by CDM and PBO. The toxicity of the pesticides was time-dependent and increased over time from 24, 48, to 72 h of exposure in all experiments. The results indicate that flupyradifurone is a promising component in future mosquito control programs.

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