Anthracnose of currants

Anthracnose of currants is a destructive fungal disease caused by the pathogen Drepanopeziza ribis. This fungus predominantly affects various species of the Ribes genus, including black, red, and white currants, as well as gooseberries. It is considered one of the most common and damaging diseases in temperate fruit-growing regions.

The primary symptoms of the infection include the appearance of numerous small, irregular brown or reddish-brown spots on the leaves. As the disease progresses, these spots expand, coalesce, and cause the foliage to wither. Small, shiny, flesh-colored fungal fruiting bodies called acervuli appear in the center of these necrotic lesions.

The development of the fungus is highly dependent on humidity and rainfall. Drepanopeziza ribis overwinters primarily in dead leaf litter, where it produces spores that are spread by rain splash and wind during the spring. Prolonged periods of damp, cool-to-moderate weather create ideal conditions for secondary infections throughout the growing season.

The economic impact of this disease is significant due to severe premature defoliation. When plants lose their leaves early in the summer, they are unable to photosynthesize effectively, which drastically reduces carbohydrate storage. This weakens the shrub, stunts growth, decreases fruit production, and makes the plant significantly more susceptible to winter frost damage.

Management strategies focus on reducing the primary inoculum by removing and disposing of fallen leaf debris during autumn or early spring. Cultural practices, such as proper pruning for improved air circulation and using drip irrigation to keep foliage dry, are essential. Fungicide applications, particularly early in the season and post-harvest, are highly effective in containing the spread of the pathogen.