Development Of 25% Pyraclostrobin Aqueous Suspension And Its Control Of Rice Sheath Blight

Pyraclostrobin is a new type of Methoxyacrylate fungicide,which has the highest activity among the methoxyacrylic fungicides.It comes from the natural product of?-methoxyacrylic acid and is a kind of bionic pesticide.It has unique fungicidal activity and is the first fungicide registered with the function of plant health care.Based on the current trend of green pesticide,therefore,the environment-friend product type of pyraclostrobin has more research value.Pyraclostrobin has a wide bactericidal spectrum and can be used in the control of rice sheath blight.In this experiment,the preparation content of pyraclostrobin suspension concentrate?SC?was 25%,the main technical material provided by six domestic companies producing pyraclostrobin was used as raw materials,and the main active ingredient with high melting point was screened out by image particle analyzer and incubator stored at 60?for 24 hours to be used for the preparation of suspension concentrate;the wetting dispersing agent was screened out by flow point method;the optimal formula was determined by orthogonal experiment;the appropriate sanding temperature was screened out to be used for the preparation of SC;Through the laboratory bioassay test,the inhibitory effect of the qualified samples on the pathogen of rice sheath blight was determined;the 250 g/L pyraclostrobin EC was used for the control of rice sheath blight,the disease index was recorded,the control effect was calculated,and the yield and residue were measured during the harvest period.In this experiment,it was found that the technical material of Kangqiao in Shandong Province had no melting point and high melting point after being stored for 24 hours at 60?in the incubator made by six manufacturers,which could be used for the preparation of 25%pyraclostrobin SC.The optimal formulation was determined by flow point value and orthogonal test as follows:wetting dispersant THB1?2%?,THB2?4%?,antifreeze glycol?5%?,tackifier xanthan gum?0.15%?;the sanding temperature was controlled at 10%;The results of the indoor bioassay showed that when the concentration of the agent was 20 mg/L,the inhibition rate was80%,and the EC₅₀0 was 8.425 mg/L,the inhibition effect was significant;the results of the field test showed that the control effect was slightly worse than that of the control sample,but the increase effect was significantly higher than that of the control sample,the increase rate was higher,and the residue was lower.The results of this study provide sufficient theoretical basis and technical support for its industrial production and application.