Disease Descriptions and Management
The diseases discussed below are common to all brambles; however, susceptibility to these diseases varies within the bramble groups. See basic cultural guidelines for the control of plant diseases under Pest Management. Table 2.4 lists pesticides available for the control of diseases on various fruit crops. Pictures of fruit diseases can be found in the Fruit Pathology Fact Sheets.
Botrytis fruit rot or gray mold is the most common and most serious disease of Rubus species worldwide.
Cane blight usually affects only canes that have been wounded in their vegetative year. It sporadically attacks canes of all Rubus species. Black raspberry is more susceptible to this disease than the other brambles.
Orange rust is a fungal disease that occurs only on brambles, particularly blackberries, dewberries, and black raspberries.
Late leaf rust can be a problem on fall-bearing raspberries.
Blackberries are seldom severely infected by powdery mildew. It is occasionally a serious problem on susceptible varieties of red and black raspberries, especially the Black Hawk and Latham varieties. Infected plants may be stunted and less productive.
Red and purple raspberries are more affected by spur blight than black raspberries. Blackberries appear to be immune.