Identification of antagonistic bacterium strain and biocontrol effects on ginseng root rot disease

From healthy mountain-cultivated ginseng leaves, 45 endophytic bacteria strains were isolated. Antagonistic bacterium strain FS17 was screened with the confront culture method, and identified as Bacillus subtilis based on morphological characteristic and 16S rRNA sequence analysis. Growth rate method was used to determine that the fermentation broth of FS17 had inhibitory effect on 10 plant pathogenic fungi, and the inhibition rate ranged from 46.83 to 93.25%. The fermentation broth of strain FS17 with lower disease incidence and lesion diameter had better control effects with no significant difference compared with that of carbendazim. This study suggests that strain FS17 showed strong inhibition effect and wide antagonistic spectrum, and could be useful to effectively control Cylindrocarpon destructans causing ginseng root rot.