Biotic characteristics in the deltamethrin-susceptible and resistant strains of Culex pipiens pallens (Diptera: Culicidae) in China

Abstract

Culex pipiens pallens was selected with deltamethrin for 12 generations, and the LC50 value rose steadily from 0.040 mg/l to 24.660 mg/l (617 times). The biotic parameters were observed for the deltamethrin-susceptible (SS) and resistant (RR) strains of C. pipiens pallens in the laboratory. In the RR strain, the fecundity, percentage of pupation and emergence decreased by 44.8%, 17.6% and 8.9% respectively; the percentage of scattered eggs increased by 22.5%; the time from hatching to emergence was prolonged by 1.32 days; the weight of female and male adults increased by 0.202 mg and 0.231 mg, respectively; and the life-span of the female and male adults was reduced by 4.13 days and 4.74 days, respectively. The results indicated that deltamethrin resistance of the mosquito was correlated with disadvantages during reproduction.