Gooseberry Powdery Mildew
American Gooseberry Mildew (Sphaerotheca mors-uvae) is the most common and economically damaging disease to affect both gooseberry and currant bushes.
The disease is first seen from April onwards as white fungal threads covering the small shoots. These fungal threads produce large quantities of conidial spores that are readily dispersed and attack fresh new growth. Later in the season a more severe infection can develop on the stems and berries consisting of a brown mycelium.
The berries will then drop from the plant and those that remain are normally small and unsightly. The brown felt like mycelium remain on the bushes over the winter probably in the buds. These act as a major source of infection for the following spring.