Currant rust mite

The currant rust mite (Epitrimerus trilobus) is a microscopic mite belonging to the family Eriophyidae. It is a significant pest of blackcurrant (Ribes nigrum) and occasionally infests redcurrant and gooseberry plants, causing substantial economic losses in commercial and private berry production.

The pest primarily targets the young foliage of the host plant. By feeding on the leaf surface, the mites cause mechanical damage and disrupt plant physiology. The resulting stress leads to decreased vigor, reduced leaf size, and stunted growth of the entire plant, which significantly impacts the fruit yield and overall quality.

Regarding its biology, the species overwinters as adult females, typically hidden within dormant buds or under the bark of the shoots. As temperatures rise in early spring, the mites migrate to the newly unfolding leaves. The life cycle is quite short, allowing for multiple generations to develop during the warm summer months, especially in humid conditions.

Symptoms of an infestation are quite characteristic:

• Curling and distortion of the leaves;
• Development of a wrinkled or rugose appearance;
• Yellowing of leaf margins;
• General retardation in plant development.

Effective management requires an integrated approach. Cultural practices such as selecting resistant cultivars and pruning affected shoots are fundamental. Chemical control involves the application of acaricides during the pre-flowering stage or post-harvest period. It is vital to rotate different chemical classes to prevent the development of pesticide resistance in the mite population.