Differential antagonistic responses of Bacillus pumilus MSUA3 against Rhizoctonia solani and Fusarium oxysporum causing fungal diseases in Fagopyrum esculentum Moench

Microbiol Res. 2017 Dec:205:40-47. doi: 10.1016/j.micres.2017.08.012. Epub 2017 Sep 5.

Abstract

Chitinase and surfactin-mediated biocontrol of Rhizoctonia solani and Fusarium oxysporum causing wilt and root rot of Fagopyrum esculentum respectively has been studied in this communication. Bacillus pumilus MSUA3 as a potential bacterial strain strongly inhibited the growth of R. solani and F. oxysporum involving the chitinolytic enzymes and an antibiotic surfactin. Plant growth promoting attributes seem to be involved in plant growth promotion and yield attributes. The action of cell-free culture supernatant (CFCS) was found deleterious to F. oxysporum and R. solani even in the heat-treated (boiled/autoclaved) CFCS. The possible involvement of surfactin in disease control was revealed by colony PCR amplification of SrfA. Chitinolytic enzyme and antibiotic surfactin evidenced differential biocontrol of F. oxysporum and R. solani by B. pumilus MSUA3. A significant reduction in disease index under gnotobiotic conditions and productivity enhancement of F. esculentum using vermiculite-based bioformulation revealed B. pumilus MSUA3 as a successful potential biocontrol agent (BCA) and an efficient plant growth promoting rhizobacterium (PGPR) for disease management and productivity enhancement of buckwheat crop.

Keywords: Bacillus pumilus; Biocontrol; Fagopyrum esculentum; Fusarium oxysporum; Rhizoctonia solani; Surfactin.

MeSH terms

  • Antibiosis*
  • Antifungal Agents / metabolism
  • Bacillus pumilus / classification
  • Bacillus pumilus / genetics
  • Bacillus pumilus / isolation & purification
  • Bacillus pumilus / physiology*
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Biological Control Agents*
  • Chitinases / metabolism
  • Fagopyrum / growth & development
  • Fagopyrum / microbiology*
  • Fusarium / growth & development
  • Fusarium / pathogenicity
  • Fusarium / physiology*
  • Mycoses*
  • Peptide Synthases / genetics
  • Peptide Synthases / metabolism
  • Phylogeny
  • Plant Development
  • Plant Diseases / microbiology
  • Plant Diseases / prevention & control
  • Plant Roots / microbiology
  • Rhizoctonia / growth & development
  • Rhizoctonia / pathogenicity
  • Rhizoctonia / physiology*
  • Soil Microbiology
  • Surface-Active Agents / metabolism
  • Surface-Active Agents / pharmacology

Substances

  • Antifungal Agents
  • Bacterial Proteins
  • Biological Control Agents
  • Surface-Active Agents
  • Chitinases
  • Peptide Synthases