Control Effects of Pyraoxystrobin on Cucumber Powdery Mildew

The control effects of pyraoxystrobin on cucumber powdery mildew were tested in greenhouses and fields. The greenhouse trial results demonstrated that pyraoxystrobin expressed an excellent protection and control activities to cucumber powdery mildew, the EC50 of protection activity and control activities were 13.20 and 26.60 mg/L, and the control effects were 79.65% and 77.54%. The field trials showed that application of pyraoxystrobin 20% SC after infection could effective control powdery mildew, 7 days after the 3rd round of application, the control efficacy of 250 mg/L was 74.07%.