Differentiation of Xanthomonas albilineans strains with monoclonal antibody reaction patterns and DNA fingerprints

Thirty-eight strains of the sugarcane leaf scald pathogen, Xanthomonas albilineans, were compared using a series of seven species-specific monoclonal antibodies as well as genomic DNA fingerprint patterns. The strains, which were obtained from 13 countries and states in the USA, were placed in three major groups with approximately eight subgroups based on similarity of their serological reactions. The serological groupings correlated strongly with groupings based on DNA fingerprint patterns. The groups of strains that were genetically and serologically related did not necessarily come from nearby locations but were usually from widely separated regions. Thus, it appears that disease transmission occurred by means other than natural spread. The methods used in this study are useful for comparing relationships among strains of X. albilineans. A combination of the monoclonal antibodies could be used in a serodiagnostic-based method to test for the presence of leaf scald disease.