Bacterial blight is a serious disease affecting a large number of deciduous woody ornamentals in nurseries.
Economic losses vary between years.
Because the pathogen can survive on healthy woody plants and weeds, inoculum is always present in the nursery. In the spring, when weather conditions are favorable, bacterial populations can increase very rapidly and disease losses can be severe. The Pathogen Bacterial blight is caused by Pseudomonas syringae pv. It is a relatively weak pathogen that requires a large population size and plants with wounds or in poor health. First identified on lilac, the host range of these bacteria is very broad, including most of the deciduous woody plants and ornamental fruit trees grown in nurseries.