Insecticide Effects of Amitraz Mixing with Fenvalerate or Cypermethrin against Myzus persicae (Sulzer)

The synergistic toxicities of mixed insecticides, Amitraz with Fenvalerate or Cypermethrin, for Myzus persicae (Sulzer) were determined with immersion method.The results showed that the synergistic effects of the insecticides were enhanced when the ratios of Amitraz to Fenvalerate were 1:2, 1:5 and 2:1, and those of Amitraz to Cypermenthrin were 1:1, 1:2, 2:1 and 5:1.The highest co-toxicity coefficients were achieved when the ratios of Amitraz to Fenvalerate and Cypermenthrin were 1:2 and 1:1 respectively.The control of Myzus persicae (Sulzer) with mixture of Amitraz and pyrethroids was also studied.