The bacterium Pseudomonas savastanoi pv. nerii was identified as the causal agent of parenchymatous galls on leaves of potted oleander plants ... The leaf galls on the oleander sample resembled bacterial knot. Similar diseases occur on common ash (Fraxinus excelsior L.), olive (Olea europea L.), privet (Ligustrum japonicum Thunb.) and species of Jasminus, Forsythia, and Phyllyrea among Oleaceae ... Recently, strains isolated from oleander (Apocynaceae), from ash and from olive and other Oleaceae have been classified, respectively, as P. savastanoi pv. nerii, P. savastanoi pv. fraxini, P. savastanoi, and P. savastanoi pv. savastanoi ... Oleander strains infect oleander and plants of Oleaceae

[photos of leaf and fruit galls]