Objective To investigate the resistance of Culex pipiens pallens larva to insecticide in Nanjing and provide scientific evidence for its control.Methods Larva immersion method.Results Culex pipiens pallens larva had the medium resistance to DDVP.The LC50 was 0.272 8 mg/L.It had low resistance to beta-cypermethrin.The LC50 was 0.001 0 mg/L.It had susceptible to deltamethrin,temephos and fenobucarb.The LC50 was 0.001 8,0.000 8 and 0.082 5 mg/L.Conclusion For mosquito control in Nanjing,the application of dich...