Screening Of Control Agents For Grape Powdery Mildew In Linyi District Of Weinan City

Linwei grape is the local pillar industry in Linwei City of Weinan City.The planting area is increasing.the occurrence of powdery mildew due to the increase in the area of the facility,Powdery mildew is one of the most important diseases that harm many crops,the occurrence of powdery mildew has seriously affected the yield and quality of grapes,has become a limiting factor in the development of the local grape industry.This paper selects grape powdery mildew as the research object,Seven medicinal agents were selected to test the virulence of grape powdery mildew and the field efficacy test.Through the test,the agent which is better in controlling grape powdery mildew is selected.The results of pot experiment showed that several different types of test agents had different inhibitory effect.Among them,1%osthole soluble liquid has the highest inhibitory effec,highest activity.the EC₅₀ is 1.64?g·mL^-1.75%bupirimate emulsifiable concentrate has the worst inhibitory effect on grape powdery mildew,the EC₅₀0 is340.83?g·mL^-1.The EC₅₀ of 25%Penconazole emulsion in water,50%trifloxystrobin in the test agent Water dispersible granule,5%hexaconazole hexaconazole,75%chlorothalonil water power,36%thiophanate-methyl suspension concentrate was respectively 5.86?g·mL^-1?1.22?g·mL^-1?5.53?g·mL^-1?199.35?g·mL^-1?96.31?g·mL^-1?In the field efficacy test:50%trifloxystrobin in the test agent Water dispersible granule 1500 times,75%bupirimate emulsifiable concentrate500 times,36%thiophanate-methyl suspension concentrate 800 times These three agents have obvious effects in controlling grape powdery mildew,The control effect has reached about 85%;5%hexaconazole hexaconazole 8000 times,1%osthole soluble liquid 1000 times has a better control effect.The control effect reached 79.42%and 80.23%respectively;75%bupirimate emulsifiable concentrate 700 times,25%Penconazole emulsion in water 10000 times,75%chlorothalonil water power 700 times has a poor control effect.The control effects were73.60%,59.13%,and 60.12%,respectively.Through the test data:trifloxystrobin,bupirimate,thiophanate-methyl has good control effect on grape powdery mildew,in the early stage of the onset of grape powdery mildew or in the early stage of the disease,the whole plant is evenly sprayed for prevention and treatment,The recommended interval between 7 and 10 days is recommended,2 to 3 times of application,Mix or alternate with other fungicides with different mechanisms of action,further improve the control effect.