Screening of insecticides and its application method for controlling Quadrastichus erythrinae

In order to screen insecticides and its application method for controlling Quadrastichus erythrinae,the three different methods such as trunk injection method,foliar spraying method and root zone drenches method were used to evaluate the effects of different insecticides on the field. The results indicated that the effects of foliar spraying method was the best of the three methods and the insecticidal effects of pesticide 16% quinalphos·carbosulfan EC was better than those of other pesticides with spraying methods. The emergence rates of adults of Q. erythrinae were 2. 79% and 9. 41% ,and the mortality of adults were 97. 21% and 90. 60% ,respectively after treatment for 10 d and 15 d with 16% quinalphos·carbosulfan EC which was diluted for 200 times with foliar spraying methods. The concentration of quinalphos was 287. 45 and 221. 57 mg·kg-1 and that of carbosulfan was 225. 64 and 187. 62 mg·kg-1 respectively,after treatment with 16% quinalphos·carbosulfan EC diluted for 200 times with foliar spraying methods for 1 d and 10 d,and the control efficacies were expected to correlate with the quinalphos and carbosulfan levels and the duration. It was suggested that 16% quinalphos·carbosulfan EC diluted for 200 times was an effective pesticide and worth spreading and application to control Q. erythrinae in the field.