Effects of space spray application methods on fenitrothion efficacy and development of resistance in Culex pipiens.

Efficacy of fenitrothion as thermal fogging (TF) or ultra-low volume (ULV) applications against 6 successive generations of caged adult Culex pipiens and subsequent development of resistance in both adults and larvae were investigated in this study. In addition, larval acetylcholinesterase (AChE) activity was measured in each generation. Results indicated that the ULV application method was significantly more effective (P < 0.