Title: Screening of Bacillus sp. antagonistic to Burkholderia glumae and effective in preventing bacterial panicle blight disease of rice in net-house conditions

The study was conducted in the laboratory and greenhouse to select Bacillus strtains effective in preventing the bacterial panicle blight disease caused by Burkholderia glumae. From the preliminary assessment results in in vitro conditions, 19 strains of Bacillus spp., were further assessed for their antagonism against B. glumae- Bg-AG9, compared with 3 chemical drugs. From the results, Bacillus  strains B-THDT3, B-PTAG1, B-PTAG12, with the best antagonistic ability, i.e. owned high antagonistic radius (mm) of 16.2; 15.8 and 14.4 respectively, higher than that of Starner 20WP (13.0) at 7 days after testing, were selected for evaluating their effectiveness in the control of bacterial panicle blight disease. The pot experiment in net house conditions on OM4900 rice variety included factor (A) 5 treatment agents (3 strains of Bacillus, Starner 20WP and control and (B) 3 ways of handling), was arranged randomly, with 4 replications, each is a rice pot. The results showed that all 3 Bacillus strains (i.e. B-THDT3, B-PTAG1, B-PTAG12) showed high prevention of bacterial panicle blight disease, no difference between 3 ways of handling (1 day before, 1 day after infection or combination) and equivalent to that of Starner 20WP (1,26 ‰) treatment.

Keywords: Bacillus, Burkholderia glumae, Biocontrol, Starner