Approximately 94% of the total 16S rDNA of Pseudomonas andropogonis strain ACH 01053A was sequenced and compared with that of strain ATCC 23061 obtained from the GenBank database. The two sequences were highly homologous with 1.3% difference. Alignment of sequences with those from closely related bacteria revealed two possible regions for design of a specific primer suitable for detection of Ps. andropogonis. Using primers designed to these variable regions in a PCR test, an amplification product of approximately 410 bp was specifically produced by 40 strains of Ps. andropogonis. No other bacterial species showed an amplification product under optimized PCR conditions. As few as 1000 cells per reaction were detected.