Biocontrol of Soft Rot Caused by Pectobacterium odoriferum with Bacteriophage phiPccP-1 in Kimchi Cabbage

Pectobacterium odoriferum has recently emerged as a widely infective and destructive pathogen causing soft-rot disease in various vegetables. Bacteriophage phiPccP-1 isolated from Pyeongchang, South Korea, showed lytic activity against P. odoriferum Pco14 and two other Pectobacterium species. The transmission electron microscopy and genome phylograms revealed that phiPccP-1 belongs to the Unyawovirus genus, Studiervirinae subfamily of the Autographivirinae family. Genome comparison showed that its 40,487 bp double-stranded DNA genome shares significant similarity with Pectobacterium phage DU_PP_II with the identity reaching 98% of the genome. The phiPccP-1 application significantly inhibited the development of soft-rot disease in the mature leaves of the harvested Kimchi cabbage up to 48 h after Pco14 inoculation compared to the untreated leaves, suggesting that phiPccP-1 can protect Kimchi cabbage from soft-rot disease after harvest. Remarkably, bioassays with phiPccP-1 in Kimchi cabbage seedlings grown in the growth chamber successfully demonstrated its prophylactic and therapeutic potential in the control of bacterial soft-rot disease in Kimchi cabbage. These results indicate that bacteriophage phiPccP-1 can be used as a potential biological agent for controlling soft rot disease in Kimchi cabbage.