Huanglongbing (yellow dragon disease) is a destructive disease of citrus. The etiological agent is a noncultured, phloem-restricted alpha-proteobacterium, “
Liberibacter africanus” in Africa and “
Liberibacter asiaticus” in Asia. In this study, we used an
-based PCR-restriction fragment length polymorphism (RFLP) approach to analyze the genetic variability of “
. Liberibacter asiaticus” isolates. By using five different enzymes, each the 10 isolates tested could be associated with a specific combination of restriction profiles. The results indicate that the species “
. Liberibacter asiaticus,” even within a given region, may comprise several different variants. Thus,
-based PCR-RFLP analysis is a simple method for detecting and differentiating “
. Liberibacter asiaticus” isolates.