Currant flower midge

The Currant flower midge (Contarinia ribis) belongs to the order Diptera and the family Cecidomyiidae. It is a specific pest that primarily infests black currant bushes, occasionally attacking red currants and gooseberries in commercial and private gardens.

The biology of the midge is synchronized with the phenological development of the host plant. The insect overwinters as a mature larva in the soil, protected by a cocoon. As the currants enter the bud stage in spring, the larvae pupate, and adult midges emerge to begin the mating and oviposition process.

Female midges lay their eggs inside the developing flower buds. Upon hatching, the larvae feed on the internal floral parts, such as stamens and pistils. This feeding activity disrupts normal growth, causing the buds to swell into globular, deformed shapes that fail to open.

The economic impact of this pest is significant, as the damaged buds turn yellow or red and drop off before fruit set occurs. In cases of heavy infestation, the midge can cause substantial yield loss, sometimes destroying more than half of the potential crop if left unmanaged.

Integrated pest management strategies include cultivating the soil around the base of the bushes to disrupt the overwintering pupae. Additionally, applying suitable insecticides during the late bud stage, just before the flowers open, is essential to kill the adults before they can lay their eggs.