All isolates, when inoculated into tomato and pepper, caused hypersensitive reactions (HR), indicating they were likely phytopathogenic. Further testing was conducted to confirm and to characterize the causal agent of what appeared to be a new citrus bacterial disease. In this paper, we describe bacterial brown leaf spot, anew, opportunistic bacterial disease of citrus in Florida, and identify the causal agent to be B. andropogonis. Furthermore, we have devel oped a simple and ripid genetic typing method for differentiating B. andropogonis strains using a simple PCR test based on a single primer.