Abstract: Wettable powder and aqueous solutions is the main type of microbial pesticide formulations in China. However, dry flowable formulations that safety and effective have been becoming important in the application of bioagent. Dual culturing experiment showed that inhibition zones of four Bacillus amyloliquefaciens T429, JT84, Lx-11, B-916 dry flowable formulations against Magnaporthe oryzae were 12.00, 10.33, 7.67 and 7.50 mm, respectively. Inhibition zones of lipopeptides from dry flowable formulations against M. oryzae were 7.00, 6.33, 5.50 and 5.00 mm. Mycelium of M. oryzae exhibited obviously swelled by microscopic observations. Thus it can be seen that lipopeptides still exist in the dry flowable formulations. It was show that control effects ofB. amyloliquefaciens T429, JT84, Lx-11 and B-916 dry flowable formulations against rice blast were 85.2%, 79.3%, 79.6% and 78.9% in field trials. When treated rice seeds with four 500 times diluted dry flowable formulations supernatant, there were not only no toxic effects but also varying degrees of growth promotion. The storage stability measured was found that the number of spores did not decreased significantly in 90 days. After 180 days storage, spores in flowable formulations of T429 and B-916 had no significant changes, but decreased 30% in Lx-11 and JT84 dry flowable formulations were observed. After 360 days storage, every strain remained viable cell count above the 1×10⁹cfu/mL.

Key words: dry flowable formulations, Bacillus amyloliquefaciens, rice blast