Laboratory evaluation of two organophosphate and one pyrethroid insecticide against the Culex quinquefasciatus (Say) (Diptera: Culicidae) mosquito larvae (original) (raw)
Related papers
2020
This study aimed to investigate the mosquito larvicidal efficacy of pyrethroids (deltamethrin, cypermethrin and lambda cyhalothrin), organophosphates (chloropyrifos and dichlorvos) and a neonicotinoid (acetamiprid) against Culex quinquefasciatus of Chakdara, Dir Lower, Khyber Pakhtunkhwa Pakistan. Fourth instar larvae of Culex quinquefasciatus were initially exposed to various concentrations (0.001 to 1.0 ppm) of these insecticides to determine the activity concentration ranges. The highest concentrations of deltamethrin, cypermethrin, lambda cyhalothrin, chloropyrifos, dichlorvos and acetamiprid that showed no insecticidal activity against Culex quinquefasciatus 4th instar larvae were 0.001, 0.0005, 0.000015, 0.001, 0.0005 and 0.001 ppm, respectively. The lowest concentration of these insecticides that were capable of insecticidal activity against mosquito larvae were 0.002, 0.001, 0.000031, 0.002, 0.001 and 0.002 ppm, respectively. The lowest concentrations of these insecticides t...
Evaluation of some insecticides against Culex pipiens, the dominant mosquito species in Abha city
— The present study was planned to test on certain chemical insecticides from different groups such as organophosphates, pyrethroids and Bioinsecticide. Among these compounds two were chemical insecticides (Propetamphos and Cypermethrin), while the third one is Bioinsecticide (Baciloid 5000: Bacillus thuringiensis) against Culex pipiens, the dominant mosquito species in Abha city. Taking LC50 values (concentration which to kill 50% of mosquito larvae) into consideration, mosquito larvae of CX. Pipes against Propetamphos was effective (LC50 0.0162 ppm) against the 3rd instar of the laboratory strain comparing with a field strain which was 0.0442 ppm. At LC90 level, data indicated that Propetamphos (LC90 0.8109 ppm) was effective insecticide against the 3rd instar larvae of laboratory strain, while against field strain gave (LC90 3.31 ppm). Similarly, the results clearly showed that Cypermethrin was also very effective insecticide (LC50 0.0132 ppm) against the adult females against laboratory strain, while against field strain Cypermethrin gave (LC50 0.1192 ppm). On the other hand, the residual activity of Bacillus thuringiensis var. israelensis reached from 4 to 20 days of concentrations ranged between 0.001 to 100 p.m. in case laboratory strain, while reaching between 6-23 days of concentrations ranged between 0.001 to 100 p.m. in case field strain. Mortality percent was also found between 11.7 to 96.8% of concentrations ranged between 0.001 to 100 p.m. against laboratory strain in the 1st week, whereas ranged between 0.0 to 70.8% in the 2nd week against the same concentrations finally ranged between 0.0 to 12.7% in the 3rd week. Hence, the field collected larvae of Culex pipens were more susceptible and have prolonged residual effect as compared to laboratory reared. Keywords— Evaluation of insecticides against Culex pipiens, in Abha city.
Unique Efficacy of certain Novel Herbicides against Culex pipiens (Diptera: Culicidae) Mosquito under Laboratory Conditions, 2016
Background: Culex pipiens is considered as serious pest all over the world which transfers remarkable transmitted diseases. Objective: Toxicity of pyrethriod insecticide, deltamethrin, the three acetyl CoA carboxylase (ACCase)-inhibitor herbicides fenoxaprop-p-ethyl, fluazifop-p-butyl and clethodim, and two enzyme, 5-enolpyruvyl-shikimate-3-phosphate synthase (EPSP synthase inhibitor herbicides, glufosinate-ammonium and glyphosate-isopropyl ammonium against the fourth instar larvae of Culex pipiens complex (Diptera, Culicidae) after 24, 48, 72-h of exposure were evaluated in the laboratory and expressed as LC50 and LC90 in mg L-1 (mg a.i L-1). Results: Results indicated that all the tested pesticides exhibited toxicity against the fourth instar larvae of C. pipiens, and the toxicity increased after 48 and 72-h when compared with the 24-h results. The pyrethriod insecticide deltamethrin was the most toxic pesticide among the tested pesticides especially after 72-h. Although ACCase-inhibitor herbicides were designed to kill and inhibit grassy weeds it also showed toxicity and reduction in survival of C. pipiens larvae. Among the tested herbicides, fenoxaprop-p-ethyl and fluazifop-p-butyl were the most potent herbicides against the fourth instar larvae of C. pipiens after 24, 48, and 72-h of exposure while clethodim was the least toxic pesticide. Conclusion: This study is considered the first report on the toxicity effects of fenoxaprop-p-ethyl, fluazifop-p-butyl and clethodim on C. pipiens larvae in Africa particular in Egypt.
Journal of environmental biology / Academy of Environmental Biology, India, 2007
Relative susceptibility of three important mosquito vector larvae viz., Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus, prevalent in the arid region was determined against four organophosphates (malathion, fenitrothion, fenthion, temephos) and three synthetic pyrethroid (alphamethrin, deltamethrin and fanvalerate) compounds. Studies were carried out on late 3rd or early 4th instar larvae of these species using standard WHO technique. Based on concentration mortality data LC50 and LC90 values along with their fiducial limits, regression equation, chi-square (chi2)/heterogeneity of the response have been determined by log probit regression analysis. LC50 values as observed for the above seven insecticides were 0.8097, 0.0398. 0.0432, 0.0035, 0.0025, 0.0092, 0.1006; 1.2370, 0.0531, 0.0655, 0.0076, 0.00004, 0.00004, 0.0046 and 1.4980, 0.0719, 0.0817, 0.0056, 0.00021, 0.00073, 0.0112 mg/l for the above three mosquito species respectively Among the four organophosphates tes...
Journal of the Egyptian Society of Parasitology
The present study was tested certain chemical insecticides (Propetamphos and Cypermethrin) and a Bioinsecticide (Baciloid 5000: Bacillus thuringiensis) against Culex pippins, the dominant mosquito species in Abha City. LC 50 value of Propetamphos was 0.0162 ppm against the 3 rd instar larvae of laboratory strain compared with field strain which was 0.0442 ppm, and LC 90 of Propetamphos was 0.8109 ppm against the 3rd instar larvae of laboratory strain, comparing to field strain (3.31ppm). Cypermethrin was also very effective where LC50 was 0.0132 ppm against the adult females of laboratory strain, comparing to (0.1192 ppm) of laboratory strain. On the other hand, residual activity of Bacillus thuringiensis var. israelensis reached from 4 to 20 days of concentrations ranged between 0.001 to 100 ppm (lethality was 11.7 to 96.8%) in laboratory strain in the 1 st week, whereas ranged between 0.0 to 70.8% in the 2 nd week with same concentrations finally ranged between 0.0 to 12.7% in the 3 rd week. While reached 6-23 days at concentrations 0.001 to 100ppm in field strain in the 1 st week, whereas ranged between 0.0 to 70.8% in the 2n d week with the same concentrations and ranged between 0.0 to 12.7% in the 3 rd week. So, the field collected larvae of Cx. pipens were more susceptible and have prolonged residual effect as compared to laboratory reared larvae.
Animal Research International, 2017
Laboratory evaluation of Bendiocarb and Deltamethrin insecticides for the management of Culex quinquefasciatus mosquitoes were conducted in June, 2016 at Arbovirus and Vectors Research Centre, Enugu, Nigeria. Cx. quinquefasciatus larvae were obtained from breeding sites (ground pools, dirty water, containers) at Michael Okpara University of Agriculture, Umudike, Southeast Nigeria. They were reared and fed with ground biscuit to adulthood. Two- to three-day old, non-blood engorged female mosquitoes were exposed separately to discriminating dosages of 0.1 % bendiocarb and 0.05 % deltamethrin-impregnated papers embedded in World Health Organisation (WHO) diagnostic test kit following their standard protocol of susceptibilities. Knockdown effect was recorded at 5 and 10 minutes intervals, and their mortality scored 24 hours after exposure. Fifty and ninety percent knockdown times (KDT 50 and KDT 90 ) were determined using probit analysis. The result showed that the Cx. quinquefasciatus ...
Toxicological and Biochemical Investigation of certain Herbicides on Culex pipiens L. (Diptera: Culicidae) Mosquitoes under Laboratory Conditions, 2018
The knowledge of how herbicides affect mosquito ecology and behavior is confined. This study evaluated the toxicity of six selected herbicides in comparison with one insecticide (thiamethoxam+ chlorantraniliprole) on 4th instar larvae of Culex pipiens after 24, 48, and 72-h exposure. Plus, this study investigated the biochemical effects of these pesticides on 4th instar larvae using sodium dodecylsulphate-total protein (SDS-total protein) technique. As a result, thiamethoxam+chlorantraniliprole was the most toxic pesticide among all tested pesticides (LC50 was 0.0083, 0.0016, and 0.0004 µg/ml after 24, 48, and 72-h exposure, respectively) while mesosulfuron-methyl+iodosulfuron-methyl is considered the most potent herbicide among the evaluated herbicides (LC50 was 0.67, 0.45, and 0.36 µg/ml after 24, 48, and 72-h exposure, respectively). Clodinafop-ropargyl+ pinoxaden, diclofop-methyl, bromoxynil octanoate, and fenoxaprop-p-ethyl were demonstrated to be of moderate toxic herbicides on the mosquito larvae. In biochemical studies, new bands of protein were found rather than those in the control. For instance, Three new bands with molecular weight of approximately 41, 22, and 19 kDa were detected in Culex pipiens larvae samples treated in the same of these herbicides with glyphosate isopropylamine, diclofopmethyl, and mesosulfuron-methyl+iodosulfuron-methyl. Future studies should be conducted to investigate the mechanisms of the selected herbicides that induced changes in mosquito to get better comprehension of these functions.
Toxicity of 25 synthetic insecticides to the field population of Culex quinquefasciatus Say
The Culex quinquefaciatus Say, commonly known as the southern house mosquito, is well known for biting nuisance and vectoring of some fatal diseases. Synthetic chemicals have been relied upon as the major control measure to control mosquitoes. Therefore, we have evaluated 21 insecticides belonging to different chemical classes for their toxicity to C. quinquefaciatus females. Chlorfenapyr was the most toxic adulticide among all the tested insecticides. Among py-rethroids, deltamethrin was the least toxic adulticide, and all other have same toxicity. In case of organophosphates, the chlorpyrifos was the most toxic insecticide. Neonicotinoids such as acetamiprid, nitenpyram, and clothianidin have similar toxicity based on overlapping of 95 % confidence intervals (CI) and were more toxic when compared with the imidacloprid. The spinetoram was more toxic as compared with the spinosad (based on non-overlapping 95 % Cl). In case of ketoenoles, spirotetrament was more toxic as compared with the spiromesifen. Emamectin benzoate was the most toxic insecticide when compared with fipronil and indoxacarb. We also have tested four insect growth regulators (IGRS) including lufenuron, methoxyfenozide, pyriproxyfen, and cyromazine as larvicides. The lufenuron and pyriproxyfen have similar toxicity based upon their overlapping 95 % CI and were more toxic as compared with the methoxyfenozide and cyromazine. The methoxyfenozide was the moderately toxic among all the tested IGRS, and cyromazine was the least toxic among all the tested IGRS. These results will prove helpful in effectuating an effective integrated vector management program for C. quinquefaciatus.