10th International Virology Summit
Pukyong National University, South Korea
Title: Isolation, characterization and application for phage biocontrol of bacteriophages infecting Acidovorax citrulli, the causal agent of bacterial fruit blotch
Biography: Tae-Jin Choi
Statement of Problems: Bacterial fruit blotch (BFB) is an economically important bacterial disease that has caused huge economic losses in melon and watermelon crops around the world. There is no commercially available cultivars resistance to this disease caused by bacteria Acidovorax citrulli. Mainly, two genotypes (genotype I and II) are reported in A. citrulli, in which genotype II is the main causal agent of BFB in water melon that is major problem in Korea.
Methodology & Theoretical Orientation: We have isolated more than 50 bacteriophages infecting A. citrulli, from watermelon leaf samples which were collected from different parts of Korea. Two of the isolated phages with large plaque size named as ACP17 and ACPHW were further characterized and used for phage biocontrol.
Findings: Based on electron microscope observations, ACP17 belongs to Myoviridae family with head diameter 100±5 nm and a tail length of 150±5 nm while ACPHW has a head size of 60±5 nm and tail size 180±5 nm which belongs to Siphoviridae family. Among forty A. citrulli strains, ACP17 can lyse 27 strains of which most belongs to genotype I, and ACPHW can lyse 39 strains containing group I and II. In planta assay showed that the germination rate of watermelon seeds coated with the bacteriophages was up to 80% in the presence of A. citrulli contrast to untreated seed showing no germination. Also, these germinated plants showed 100% survival in A. citrulli treated soil.
Conclusion & Significance: These results suggest the possible use of these phages as an effective bio control agent for BFB.