摘要: The first reported observation of a phytopathogenic bacterium that nowadays would be referred to the genus Xanthomonas was made in 1881 by Wakker (1883), case yellows disease hyacinths. In his brief initial report, recorded several salient features causal agent which today alert any informed phytobacteriologist likelihood species involved this hyacinth disease: yellow color bacterial mass; copious production very viscous slime; active motility bacteria (after slime had been diluted with physiological saline and thus rendered less viscous); rod shape cells.