The bacterial disease of ash (Fraxinus excelsior), caused by Pseudomonas syringae subsp. savastanoi pv. fraxini II. Etiology and taxonomic considerations.
The results of studies of various bacteria isolated from characteristic cankers are reported. A fungus associated with the disease and formerly known as Plenodomus rabenhorstii [RRM 36 : 144] is described and renamed Phoma riggenbachii. Based on biochemical, serological and pathological studies Pseudomonas syringae ssp. savastanoi pv. fraxini is proposed for the ash bacterium and pv. oleae and pv. nerii for the closely related organisms on olive and oleander respectively.