Systemic Resistance and Expression of the Pathogenesis-Related Genes Mediated by the Plant Growth-Promoting Rhizobacterium Bacillus amyloliquefaciens EXTN-1 Against Anthracnose Disease in Cucumber

  • Park, Kyung-Seok (Division of Plant Pathology, National Institute of Agricultural Science and Technology) ;
  • Ahn, Il-Pyung (Division of Plant Pathology, National Institute of Agricultural Science and Technology) ;
  • Kim, Choong-Hoe (Division of Plant Pathology, National Institute of Agricultural Science and Technology)
  • Published : 2001.03.31

Abstract

Plants have the ability to acquire an enhanced level of resistance to pathogen attack after being exposed to specific biotic stimuli. To obtain plant growth-promoting rhizobacteria inducing resistance against cucumber anthracnose by Colletotrichum orbiculare, more than 800 strains of rhizobacteria were screened in the greenhouse. Among these strains, Bacillus amyloliquefaciens solate EXTN-1 showed significant disease control efficacy on the plants. Induction of pathogenesis-related(PR-la) gene expression by EXTN-1 was assessed using tobacco plants transformed with PR-1a::$\beta$-glucuronidase(GUS) construct. GUS activities of tobacco treated with EXTN-1 and salicylic acid-treated transgenic tobacco were significantly higher than those of tobacco plants with other treatments. Gene expression analyses indicated that EXTN-1 induces the accumulation of defense-related genes of tobacco. The results showed that some defense genes are expressed by the treatment with EXTN-1 suggesting the similar resistance mechanism by salicylic acid.

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