The recognition of how glyphosate affect mosquito ecology and behavior is limited. Thus, in this study, we evaluated the
toxicity of six selected pesticides plus combination with glyphosate on 4th instar larvae of Culex pipiens after 24, 48, and 72-h
exposure. As a result, Sulfoxaflor + spinetoram and abamectin were the most toxic pesticides (LC50 was 0.084 and 0.088
ng/ml after 24-h exposure, respectively). After 48-h exposure, emamectin benzoate was the most powerful pesticide (LC50
was 0.0036 ng/ml), while sulfoxaflor + spinetoram, abamectin, and spinosad were the modest pesticides. Further,
imidacloprid was the lowest toxic pesticide (LC50 was 5.57 ng/ml). However, similar trend was achieved after 72-h exposure.
In combination with glyphosate, it significantly synergized the selected pesticides except spinosad and emamectin benzoate
after 24-h exposure. After 48 and 72-h exposure, glyphosate synergized significantly most of the selected pesticides except
spinosad (LC50 was 0.052 and 0.01 while synergistic ratio (SR) was 0.38 and 0.30 after 48 and 72-h exposure, respectively).
Based on the LT50 values, emamectin benzoate and abamectin demonstrated high efficiency against Culex pipiens (42.60 and
43.61 hours), and imidacloprid was the least effective (232.08 hours). Whereby, in the combination with glyphosate,
sulfoxaflor + spinetoram and emamectin benzoate revealed the high potency against Culex pipiens (39.16 and 43.77 hours),
and imidacloprid remain with the same trend of efficacy as lowest effective selected pesticide towards Culex pipiens (563.30
hours). Further biochemical and molecular biological experiments needs to be done for better understanding of the
mechanism of glyphosate on Culex pipiens mosquito.