Determination of Toxicity of Chlorfenapyr Combinated with Tebufenozide against Spodoptera exigua Hbner

Toxicity of Chlorfenapyr combinated with Tebufenozide at five different proportions against Spodoptera exigua Hbner were determined. The results showed that toxicity of chlorfenapyr was higher than that of tebufenozide. The LC50 of chlorfenapyr is 27.203 0 mg/L after 48 hours. The best combination ration is recommended as 1~2∶1 with cotoxicity coefficient of 219.9~254.1. Synergism between the two insecticides was significant.