A bacterial leaf spot of wisteria in Italy1

Bacterial leaf spot was observed on Wisteria sinensis in the south of Italy. Lesions on leaflets were small, round, dark brown, surrounded by an extensive yellow halo. Upon artificial inoculation, lesions similar to naturally occurring ones were reproduced. The causal organism was rod-shaped, Gram-negative, aerobic, motile by polar flagella, fluorescent. On the basis of morphological, biochemical and physiological tests, the bacterium was identified as Pseudomonas syringae pv. syringae.