The currant fruit fly deposits eggs in the developing fruit. The eggs hatch into small white maggots which feed inside the fruit. As a result, discolored blotches form on the side of the berries and the fruit drops off before maturity. To control this pest, clear up of the dropped fruit around the plant. Powdery mildew and anthroacnose are the two common fungus disease problems with currants.
Powdery mildew appears as a white mold covering harvest stems.
It can be controlled by applying lime sulphur or benlate. Anthracnose first appears as random brown spots on the upper surface of leaves. As the disease advances, the leaves yellow and drop off. Removing the fallen leaves is a control measure. You can also spray benlate in the early stages of leaf growth.