ABSTRACT
Pseudomonas syringae pv. morsprunorum, on rose, was diagnosed only four times by the OSU Plant Clinic from 1962 to 1992. This is most commonly present in cool, wet spring weather.
Symptoms Dark-brown, sunken spots appear on leaves, ower stalks, and calyx parts. Flower buds may die without opening. Black streaks appear on 1-year-old stems (Photo 10.1).
