Two Genetically Distinct Groups of Acidovorax citrulli are Present in Watermelon-growing Fields in Korea

Abstract

Bacterial fruit blotch(BFB) of cucurbits caused by Acidovorax citrulli(Acc) continues todiminish fruit yields. The aim of this study was to address whether two genetically distinctpopulations of Acc are present in watermelon-growing fields in Korea. For this purpose, weused the enterobacterial repetitive intergenic consensus polymerase chain reaction(ERIC-PCR)profiling and substrate-utilization profiles. According to the results of ERIC-PCR, group I and IIstrains showed clearly differentiated PCR-based fingerprinting profiles. Differences between groupI and II strains included amplification of unique, group-specific DNA fragments such as the1.3-, 0.28-, and 0.25-kb fragments in ERIC-PCR. Acc stains belonging to group I did not useL-leucine, whereas group II strains did use the substrate. Our results support the geneticdifferentiation of Acc strains into two groups and demonstrate that Acc strains from both groupsare previously existed in watermelon-growing fields in Korea. Information about the geneticdiversity of Acc under the present study will help scientists and managers form strategies tocontrol BFB.