Biocontrol of late blight and plant growth promotion in tomato using rhizobacterial isolates

J Microbiol Biotechnol. 2013;23(7):897-904. doi: 10.4014/jmb.1209.09069.

Abstract

Seven bacterial isolates (viz., AB05, AB10, AB11, AB12, AB14, AB15, and AB17) were derived from the rhizosphere and evaluated in terms of plant growth-promoting activities and the inhibition of Phytophthora infestans affecting tomatoes in Korea. According to 16S rDNA sequencing, a majority of the isolates are members of Bacillus, and a single isolate belongs to Paenibacillus. All seven isolates inhibited P. infestans by more than 60% in vitro. However, AB15 was the most effective, inhibiting mycelial growth of the pathogen by more than 80% in vitro and suppressing disease by 74% compared with control plants under greenhouse conditions. In a PGPR assay, all of the bacterial isolates were capable of enhancing different growth parameters (shoot/root length, fresh biomass, dry matter, and chlorophyll content) in comparison with non-inoculated control plants. AB17-treated plants in particular showed the highest enhancement in fresh biomass with 18% and 26% increments in the root and shoot biomass, respectively. However, isolate AB10 showed the highest shoot and root growth with 18% and 26% increments, respectively. Moreover, the total chlorophyll content was 14%~19% higher in treated plants.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacillus / classification
  • Bacillus / genetics
  • Bacillus / growth & development*
  • Bacillus / isolation & purification
  • Biomass
  • Chlorophyll / analysis
  • Cluster Analysis
  • DNA, Bacterial / chemistry
  • DNA, Bacterial / genetics
  • DNA, Ribosomal / chemistry
  • DNA, Ribosomal / genetics
  • Korea
  • Microbial Interactions
  • Paenibacillus / classification
  • Paenibacillus / genetics
  • Paenibacillus / growth & development*
  • Paenibacillus / isolation & purification
  • Pest Control, Biological / methods*
  • Phylogeny
  • Phytophthora infestans / growth & development
  • Plant Diseases / prevention & control*
  • RNA, Ribosomal, 16S / genetics
  • Sequence Analysis, DNA
  • Soil Microbiology
  • Solanum lycopersicum / growth & development*
  • Solanum lycopersicum / microbiology*

Substances

  • DNA, Bacterial
  • DNA, Ribosomal
  • RNA, Ribosomal, 16S
  • Chlorophyll