One hundred and twenty bacterial strains were isolated from rice plants collected in Hau Giang province. The results have identified a number of bacterial antagonists capable of inhibitiing the growth of R. solani in which seventeenth expressed outstanding isolates were selected to test their antagonistic effects against three R. solani i.e. Rhiz-CTA2, Rhiz-LMJ and Rhiz-PH2 by laboratory dual plate assays. Results had showed three strong bacterial antagonists were LM2. l 5et, LM3. l 6et, and P H5. 8et with inhibition zone radius reached 31.0 mm, 33.0 mm and 31.0 mm, respectively. In addition, chitinase activity assay on chitin medium showed that three bacterial strains LM2. J 5et, LM3. l 6et, P H5. 8et have expressed the chitinolytic activity, with the chitin lysed halo radius of 14.67 mm, 14.33 mm and 17.67 mm, respectively at twenty days after testing.

Our findings suggest that LM2. J 5et, LM3. l 6et, P H5. Bet which belong to the Bacillus group can serve as potential biocontrol of rice sheath blight disease, are needed to study such as the production of cellulose and protease might included in antagonistic ability against R. solani.