title: Biological characteristics of Bacillus amyloliquefaciens AK-0 and suppression of ginseng root rot caused by Cylindrocarpon destructans.
abstract: OBJECTIVE
  The effect of Bacillus amyloliquefaciens AK-0 (AK-0) on ginseng root rot disease caused by Cylindrocarpon destructans was investigated.
  
  
  RESULTS
  From 190 ginseng rhizosphere bacteria, AK-0 was selected for further analysis; its morphological characteristics were investigated by microscopy. AK-0 was identified as B. amyloliquefaciens using the Biolog system, 16S rRNA gene sequence analysis and examination of morphological and biochemical characteristics. Bacterial population and media optimization were estimated by the bacterial growth curve. The number of AK-0 cells was relatively higher in brain-heart infusion (BHI) medium than in other media. The potential antifungal effect of AK-0 culture filtrate on the in vitro conidial germination of C. destructans and root rot development on root discs and 4-year-old ginseng roots were assessed. Polymerase chain reaction (PCR) analysis of antibiotic biosynthesis gene expression suggested that the release of antibiotic compounds is involved in the antifungal effect of AK-0 and the suppression of ginseng root rot.
  
  
  CONCLUSIONS
  These results indicate that the CF of AK-0 has antifungal effects on fungal pathogens of ginseng, resulting in the suppression of root rot disease caused by C. destructans.
  
  
  CONCLUSIONS
  AK-0 is a potential source of novel bioactive metabolites. AK-0 CF exhibited antifungal effects against C. destructans on ginseng roots. PCR analysis indicated that the AK-0 harbours genes involved in the biosynthesis of antimicrobial compounds.
authors.affiliation: Department of Bioresource Sciences, Andong National University, Andong, South Korea.
authors.forename: Y S
authors.initials: YS
authors.lastname: Kim
authors.affiliation: Agricultural Science and Technology Research Institute, Andong, South Korea.
authors.forename: K
authors.initials: K
authors.lastname: Balaraju
authors.affiliation: Department of Bioresource Sciences, Andong National University, Andong, South Korea.|Agricultural Science and Technology Research Institute, Andong, South Korea.
authors.forename: Y H
authors.initials: YH
authors.lastname: Jeon
mesh_terms: D000898:Antibiosis; D000069977:Bacillus amyloliquefaciens / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology*; D001419:Bacteria / Q000235:genetics; D006999:Hypocreales / Q000502:physiology*; D005894:Panax / Q000382:microbiology*; D010935:Plant Diseases / Q000382:microbiology*; D018517:Plant Roots / Q000382:microbiology; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D058441:Rhizosphere; D012988:Soil Microbiology; D013172:Spores, Fungal / Q000187:drug effects
chemical_list: D012336:RNA, Ribosomal, 16S
keywords: Bacillus amyloliquefaciens AK-0; antifungal effect; biosynthesis genes; characterization; ginseng root rot