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Dry flowable formulation of Bacillus subtilis strain T429 with fungicidal activity against the rice blast, Magnaporthe grisea, was formulated by spray-drying and tested under laboratory and field conditions.After screening of inert ingredients, the wetting agents, dispersants, disintegrants and adhesives which have good biocompatibility with Bacillus subtilis T429 were obtained.The formulation were prepared by L9 (34) orthogonal experiment as follows : the optimal content of wetting agents AEO-5, dispersants NNO, disintegrants (NH4)2SO4 and adhesives CMC-Na were 1%, 6%, 7% and 0.3%,respectively, filler kaoline added to 100%, and mixed with the fermentation broth of T429 in the ratio of 20% (M/V).After sand grinded for 3 hours, the suspension was spray-dried and the dry flowable obtained.The quality detection of the formulation illustrated good physical characteristics, such as high dispersibility and high viable bacteria spores (up to 1010cfu/g).After 12 months storage at room temperature, it showed good shelf life and viability was maintained.Field tests in rice crops showed that dry flowable formulations at 50 and 75g/667m2concentrations were as effective as a commercial fungicide, control effects of rice blast up to 77.6% and 78.5%.A comparison with chemical pesticides tricyclazole revealed no significant differences in disease control (79.5%).New shelf-stable and effective dry flowable formulation of biocontrol agent B.subtilis T429 was obtained by spray-drying for control of rice blast.