University of Manitoba - Faculty of Agricultural & Food Sciences - Plum Pocket
Plum Pocket

Problem type: Disease

Name of problem: Plum pocket

Plant name(s): Plum

Symptoms / Characteristics:
A characteristic symptom of this fungal disease is the development of abnormally large and bladder-like deformed fruit. The young seed (pit) does not develop, resulting in the production of hollow fruit. The flesh of the fruit is thick and spongy. A powdery-grey substance covers the surface of the fruit, indicating the presence of the fungal pathogen. Infected fruit eventually turns brown, shrivels and drops. Twigs and leaves also exhibit symptoms of the disease. Leaves may be curled and twigs may be swollen and deformed.

Control / Preventions:
Infected fruits and branches should be removed and destroyed in order to reduce the potential for future outbreaks. A commercial wound dressing should be applied to pruning wounds. A dormant spray may be used immediately prior to bud opening in order to prevent spring infection. A lime-sulfur spray may also be applied in the fall once the leaves have fallen. The fungus, Taphrina communis, overwinters on infected plant debris. Therefore, a thorough fall clean-up may help to reduce potential overwintering sites and subsequent infection.