The Activity Determination And Field Trial Of Azoxystrobin50%Nano Spx On The Cucumber Powdery Mildew

Powdery mildew is an important diseases of cucumber,as the planting area of greenhousecucumber growing and peasant household management, the generation of drug resistance andother factors,powdery mildew occurred more and more serious.The study use the pottedmethod for50%Azoxystrobin Nano SPX on the determination of indoor activity of cucumberpowdery mildew. Then we carried out the preparations for the safety of the cucumber testsand its field efficacy trials.Accord with the test,we measured the activity of test reagents tocucumber powdery mildew and its control effect on cucumber powdery mildew in thefield.The results are as follows:1.The prevention and treatment test of activity determination on the cucumber powderymildew with50%Azoxystrobin Nano SPX,which EC50were14.45μg/ml and17.81μg/ml.Theactivity were higher than the contrast agents of50%Azoxystrobin WG.The preventionactivity for cucumber powdery mildew is higher than the treatment activity.2.In field experiment, the test reagents in10days after the last spray prevention effect oncucumber powdery mildew was78%~87%,in20days after the last spray was73~81%;thecontrol effect in10days after the last spray was73%~83%,in20days after the last spraywas68~77%.Compared with contrast agents,the test reagents have significant control effectson cucumber powdery mildew.Under the same dose of10days after the last spray controleffect is about4%higher,and20days after the last spray control effect is about10%higher.Inconclusion,the smaller of the pesticide particles,the stronger of permeability to the plant,thebetter of control effect,the longer of pesticide effect.3.Test reagents on cucumber powdery mildew preventive effect is higher than thetreatment effect,consistent with the results of indoor activity determination.4.The test pesticide was safety for the cucumber.Compared with the pesticide treatmentarea and water control plot,we can find that plant growth is consistent and the color rate of leaves and fruits are all0.The results show that:50%Azoxystrobin Nano SPX have significant control effect of70%~90%, on cucumber powdery mildew.Under the same dose,the control effect is better,the work time is longer than the contrast agents.And the prevention effect is better than thecure.So we suggest that spray of the effective components of250~300g/ha before thecucumber powdery mildew,and alternate use the different mechanism of pesticide.