Abstract: The effects of tolfenpyrad on the behavior of worker ants of Solenopsis invicta Buren were studied by using water tube to feed poison method. After 10 h treatment with 5, 10 and 20 mg/L tolfenpyrad, respectively, the mortality rate of the small worker ants was 58.3%, 97.5% and 83.3%, much higher than that of the control group with only 10% of the mortality rate. The medium mortality rate of red fire ants was 51.7%, 86.7% and 60.0%, respectively, which was significantly higher than that of the control group with 3.3%. After 10 h treatment of 0, 5, 10 and 20 mg/L, the walking rates of small red imported fire ants was 93.3%, 31.7%, 0, 3.3%, the grasping rate was 93.3%, 21.7%, 0, 3.3%, and the climbing rate was 93.3%, 21.7%, 0, 3.3%, respectively. The walking rate of red fire ants was 96.7%, 63.3%, 8.3% and 31.7%, the grasping rate was 96.7%, 46.7%, 5.0% and 20.0%, and the climbing rate was 96.7%, 55.0%, 5.0% and 26.7%, respectively.

Key words: tolfenpyrad, Solenopsis invicta Buren, behavioral impact, control