Pest Type: Currant and Gooseberry Pest
Row: Diptera – Diptera
Family: Gall midges – Cecidomyiidae
It is found in woodland and forest-steppe. Damages currants.
Adults 2.5-3 mm long, wings gray, evenly covered with hairs; abdomen orange-yellow with two brown stripes; the female has a pointed ovipositor at the end of the abdomen. Egg 0.3-0.4 mm in size, spindle-shaped, vitreous. Larva up to 4 mm long, orange-black (white at first age).
Larvae hibernate in a cocoon in the surface soil layer at a depth of 1-8 cm, less often – under the bark of shoots in feeding places. Pupate in late April – early May. Pupa development lasts 8-14 days. Years begin in the third decade of May. Females fly out sexually mature and begin to lay eggs. The eggs are placed in small groups in the cracks of the young bark, in the wounds on the bark of the branches of the current of the first and second years. After 3-6 days, the larvae have revived, penetrate under the cortex and feed on juice. Dark depressing spots appear on the damaged areas, the skin cracks, the shoot dries out and often breaks in the same year. Less damaged shoots dry out and break in 2-3 years. Saprophytic fungi appear at the sites of damage, accelerating the death of the shoot.
In early July, having completed feeding, the larvae pass into the soil, pupate and give rise to the development of a more numerous second generation. The second-generation imago takes off in the second half of July and lasts until mid-September.
Favorable conditions for the development of Galicia are moist planting sites with a moderate temperature regime during the growing season.
The imago can fly no more than 40-45 m, therefore, the spread of quality is facilitated by wind and transport with planting material.
Protective measures. Digging the soil under the bushes in late autumn and early spring. Systematic (July-September) cutting and burning of damaged shoots of current. Prevention of mechanical damage to the branches.
When harvesting cuttings – careful rejection of damaged ones. Before flowering and, if necessary, after harvesting – treatment of currant bushes with insecticides. The economic threshold for harmfulness is 20-25% of shoots populated by the pest.