Bacterial Blight.

(Pseudomonas syringae pv syringae)
Damage: Symptoms appear from bud break to bloom. Brownish-black discoloration appears on one-year-old stems, often near branch tips. Buds and flower clusters within or adjacent to the infected stem turn brown and die. There is a distinct margin between diseased and healthy tissue on the stem.
Disease cycle: This bacterial disease is very common and spreads under cool, wet weather in the spring and fall. It often becomes severe on plants that have been damaged by frost.

Bacterial BlightCarolyn Teasdale, ES Cropconsult

Bacterial BlightCarolyn Teasdale, ES Cropconsult

Bacterial BlightSiva Sabaratnam, BCAGRI

Bacterial BlightSiva Sabaratnam, BCAGRI

 

Bacterial Blight Factsheet