Factsheet P06: Bacterial canker of plum & cherry

Bacterial canker (also called gummosis and bacterial blast) of stone fruit crops is caused by three pathovars of the bacteria Pseudomonas syringae: P.s. pv. syringae attacks all stone fruit species grown commercially; P.s. pv. morsprunum attacks cherry and plum; and P.s. pv. persicae attacks peach trees in France. This article focuses on the first two of these in relation to plums and cherries; since the essential features of the disease caused by each pathovar are essentially the same, they are henceforth treated together.