Abstract

Bacterial soft rot disease is one of the most important factors affecting potato production in Jordan. Based on biochemical and physiological analyses, Jordanian isolates of soft rot from potato were identified as Pectobacterium carotovorum subspecies carotovorum (DYE 1969). Phylogenetic analysis using pmrA gene sequence data showed that isolates from different regions were closely related to each other, whereas little genetic diversity was observed between these isolates. A DNA marker was developed from nucleotide sequences of the pmrA gene and a 318 bp fragment was polymerase chain reaction (PCR) amplified specifically from P. carotovorum subspecies carotovorum isolates, which could be used for detection of the disease in potato tubers.

Key words: Potato soft rot, Solanum tuberosum, genetic diversity, pmrA gene, Pectobacterium carotovorum subspecies carotovorum, Jordan.