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The study evaluates the resistance and susceptibility of adult female Anopheles gambiae s. l., Aedes aegypti and Culex quinquefasciatus mosquitoes sourced within Osogbo metropolis, Osun State, Nigeria to four groups of insecticides [Permethrin, Deltamethrin, Pirimiphos-methyl and DDT (Dichlorodiphenyltrichloroethane)] and the distribution of their larval habitat within the metropolis. Mosquito larvae of the three genera were collected during the wet season and reared to adult stage in the laboratory. Emerged adult female mosquitoes were exposed to insecticide impregnated papers of the four insecticide groups for 60mins using WHO kits to determine the knock down rate (kdr). Thereafter, they were transferred into holding tubes and left for 24hrs to assess their resistance and susceptibility according to the WHO protocol. Four types of larval habitats were identified (tires, ground pools, gutters and plastic containers). Anopheles gambiae s. l. showed the highest resistance to Permethrin (49%) (p = 0.04, p<0.05) while the highest susceptibility was recorded with Pirimiphos-methyl (69%) with the lowest against Permethrin (16%) (P = 0.002; p<0.05). The highest resistance of A. aegypti was against OC-Control (45%) (p = 0.031; p<0.05). Permethrin had the highest susceptibility (60%) against A. aegypti while OC-control had the lowest (11%) (p = 0.005; p< 0.05). Culex quinquefasciatus had a lower resistance to OC-control (38%) as compared with Aedes aegypti (45%). However, it was least susceptible to Pirimiphos-methyl (52%) and DDT (17%) respectively (p = 0.013; p<0.05). The susceptibility of A. gambiae s. l. and C. quinquefasciatus to Pirimiphos-methyl and A. aegypti to Permethrin is an indication of the possibility of success if employed for vector control of A. gambiae s. l., C. quinquefasciatus and A. aegypti respectively. This could be through their inclusion as active ingredients in insecticide treated nets (ITNs) and indoor residual spray (IRS) with a view to abating malaria and other life-threatening mosquito-borne diseases constituting global public health scourge., Competing Interests: The authors have declared no competing interests exist., (Copyright: © 2023 Busari et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Vector control strategies have focused on the development of effective and ecofriendly alternatives. In the present study, investigation of larvicidal and genotoxic effects of leaves of Hyptis suaveolens from four different extraction solvents (aqueous, hexane, methanol and acetone) on fourth instar larvae of Culex quinquefasciatus was carried out. Extraction was done using soxhlet apparatus and the characteristics functional group of active constituents were identified using Fourier Transform Infrared spectrophotometer. Larvicidal activities were screened using three different concentrations (50, 150 and 250 mg/mL) following WHO standard protocol and mortality was recorded after 24, 48 and 72 hr. Hexane extract showed the highest mortality (27.92, 38.75, 90.42 %; LC 50 : 272.5, 191.3, 114.8 mg/mL), followed by aqueous extract (20.83, 34.58, 59.58 %; LC 50 : 496.6, 392.9, 208.1 mg/mL) and acetone extract (20.83, 32.08, 59.58 %; LC 50 : 1111.2, 393.6, 266.1 mg/mL) and methanol extract (17.92, 29.17, 52.92 %; LC 50 : 466.0, 400.1, 272.3 mg/mL). Enzyme profile such as superoxide dismutase (SOD), glutathione-S-transferase (GST), catalase (CAT), glutathione (GSH) and alkaline phosphatase (ALP) were significantly altered in the larvae exposed to the four extracts. Phytochemical screening of all solvents extract revealed the presence of saponins, flavonoids, terpenoids and alkaloids as common constituents. Random Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR) profile implied hexane and aqueous extracts altered the DNA of larvae. Furthermore, FTIR Spectroscopic analysis revealed phenols, alcohols, aliphatic primary amines and saponins as the major groups in the extracts. Conclusively, this study established the lethal potential of extracts of H. suaveolens as alternative plant-based and eco-friendly larvicide against Cx. quinquefasciatus., (Copyright © 2022. Published by Elsevier B.V.)