Study On Application Of DAAM-BA Film Forming Agent In Rice Seed Treatment

The application of seed coating agent in preventing and controlling crop diseases and insect pests at seedling stage has become a hot spot in recent years,especially in a water environment.However,there are many problems in the application of seed coating agents,such as the high rate of fall off,the loss of effective components,and the instability of efficacy.The formulation of diacetone acrylamide-butyl acrylate copolymer was prepared by emulsion polymerization.The formulation of 40%thiamethoxam-pyraclostrobin flowable concentrate for seed coating was optimized.The film-forming agents were characterized by water-resistance and film-forming stability,and the quality indexes of seed coating were tested.At the same time,the biological properties of rice seedling treated with seed coating agent were evaluated by pot experiment,and the optimum dose was determined by laboratory test.The results showed:The diacetone acrylamide-butyl acrylate copolymer film have good film-forming stability,and dissolved slowly in water until 35 d,the abscission rate<5%.The optimum formulation of 40%thiamethoxam-pyraclostrobin flowable concentrate for seed coating is25%of thiamethoxam,15%of pyrazolemcetate,0.5%of quick T 0.5%,FS 3000 8%,0.3%of magnesium aluminum silicate,0.12%of xanthan gum and 0.5%of bentonite,5%of ethylene glycol,5%DAAM-BA and 5%of Haishu Liquid Red 2R.The abscission rate of was 3.01%,and the suspension rate was 97.9%,all the indicators of the flowable concentrate for seed coating met with the relevant suspension seed coating quality standards.The germination rate of rice seeds increased 31.98%compare to CK and 6.57%compare to positive control,plant height increased 6.48%and 9.42%compare to positive control,root activity increased 38.07%and 24.20%compare to positive control,and chlorophyll content increased 143.02%and 78.63%compare to positive control,free proline content increased28.70%and 23.79%compare to positive control.And the effect on antioxidant enzyme activity was not significant,using a drug ratio of 1:50?2.88 g a.i/kg?treatment.The EC₅₀0 of rice blast fungus was 0.007321,and the relative inhibition rate was up to97.4%at the concentration of 2 mg/L,and the half lethal concentration of 96 h was about2.46 mg/L,and the acute toxicity level was"middle poisoning".40%thiamethoxam-pyraclostrobin flowable concentrate for seed coating has good film-forming property,long persistence period,high germination rate,and safe for rice seed.As a result of the slow release of the membrane agent,the toxicity of LC₅₀0 to the zebrafish decreased by 50 times,which significantly reduced the risk of aquatic organisms.