Biological Activity of Pyraoxystrobin againstEight Vegetable Pathogens

The bioactivity of pyraoxystrobin,a recently developed fungicide,against eight fungi causing diseases on vegetables was evaluated through potted plant trails. Result indicated that pyraoxystrobin showed high activity against Botrytis cinerea,Pseudoperonospora cubensis,Colletotrichum orbiculare,Corynespora cassiicola and Cladosporium cucumerinum on cucumber,with EC50 values of 9.457, 12.69,11.09,6.453 and 4.106 mg/L,respectively. The control efficacy of pyraoxystrobin at 250 mg/L in field trial reached 75%,which was equally effective as the control pesticide of azoxystrobin. In field experiments,20% pyraoxystrobin SC at a concentration of 80 mg (a.i)./L provided control efficacy of 82.78% against P.cubensis.