This disclosure relates to a
seed treatment microcapsule suspension-suspension containing chlorantraniliprole,
fludioxonil, and
metalaxyl, and its preparation method. The method includes: 1) dispersing
metalaxyl emulsifiable concentrate in an emulsifier solution to obtain a first material; 2) mixing the first material with an aqueous
monomer solution to obtain a second material; 3) adjusting the pH of the second material to 3.5-5.0 and performing solidification and condensation to obtain a third material; 4) mixing the third material with a first dispersant, a first thickener, and an
antifreeze agent to obtain a
metalaxyl microcapsule suspension; 5) mixing the metalaxyl microcapsule suspension with a chlorantraniliprole-
fludioxonil suspension, a film-forming agent, and a colorant to form a metalaxyl-
fludioxonil-chlorantraniliprole
seed treatment microcapsule suspension-suspension. This method can increase the storage stability of the formulation, effectively prolong the effective period of metalaxyl, and at the same time, the
combined use of metalaxyl with chlorantraniliprole and fludioxonil broadens the fungicidal spectrum, effectively preventing and controlling various
seedling diseases and pests of crops.