Investigation on the insecticide resistance of Culex trituberculatus in Deyang in 2023
ZHOU Lijing
LIU Quan
YIN Yanping
LI Jinsong
Abstract：Objective To determine the resistance levels of Culex tritaeniorhynchus to commonly used insecticides,so as to provide a scientific basis for the control of Cx.tritaeniorhynchus and Japanese encephalitis.Methods According to the National Vector Surveillance Implementation Plan and the requirements of the China CDC's vector surveillance work,mosquitoes were collected by net trapping,bait trapping,and scooping method in mid-July 2023 from five different locations in Deyang(east,south,west,north,and central areas).The insecticide resistance of Cx.tritaeniorhynchus larvae and adults were measured using the larval immersion method and adult contact tube method,respectively.Results The LC50 of Cx.tritaeniorhynchus larvae in Deyang for propoxur,permethrin,beta-cypermethrin,and deltamethrin were 2.073 9,0.108 1,0.027 2,and 0.010 2 mg/L,respectively.The resistance ratios were 6.91,3.33,9.07,and 25.50,respectively.The larvae showed low resistance to propoxur,permethrin,and beta-cypermethrin,and moderate resistance to deltamethrin.The mortality rates of Cx.tritaeniorhynchus adults to deltamethrin,propoxur,malathion,permethrin,fenthion,and deltamethrin were 47.78%,83.33%,55.56%,51.11%,84.44%,and 94.44%,respectively,indicating a certain level of resistance to all tested insecticides.Conclusion Both larvae and adults of Cx.tritaeniorhynchus in Deyang have developed resistance to commonly used insecticides.In the future,targeted control measures should be adopted to delay the development of insecticide resistance.
Keywords：Culex trituberculatusinsecticideinsecticide resistance
Publication Date：2025-08-20
Online Publishing Date：2025-08-29(First online date of this platform, not the publication date of the document)
Pages：3( 484-486 )