Effect and toxicity of four pesticides on Stephanitis pyriodes

In order to control of Stephanitis pyriodes which is the main pest of Rhododendron simsii,37% beta-cypermethrin malathion,1. 8% avermectin,5% imidacloprid·cypermethrin and 10% imidacloprid were selected for toxicological test and laboratory experiments on Stephanitis pyriodes. The results showed that,all of the four pesticides were suit for controlling of Stephanitis pyriodes,the control effect of four pesticides were 100% after 5 days sprayed. The control effect of 5% imidacloprid and cypermethrin mixtures EC diluted by 1 000 times were 93. 3%,98. 9% and 100% after 1 day,2 days and 3 days sprayed respectively. The toxicity of four pesticides was 5% imidacloprid·cypermethrin 37% beta- cypermethrin malathion 1. 8% avermectin 10% imidacloprid.