Latin name: Agriotes Gurganus
Russian name: Nutcracker sowing steppe
Pest Type: Multi-Pest
Row: Coleoptera – Coleoptera
It is found everywhere, except for the sandy soils of Polesye. The zone of greatest severity covers the central forest-steppe. Beetles damage the plantings of sugar beets, larvae – sown seeds and young shoots of sugar beets, cereals, and vegetables. In autumn, the larvae harm only potatoes and are actively engaged in predation, destroying the larvae and pupae of flies and other insects.
The natural enemies of the larvae are the predatory ground beetles of the Broscus family, but they do not play a significant role in limiting their numbers.
Beetle with a size of 10 – 15 mm; the body is wide, black with a bronze sheen; front dorsum with a small dotted line, width exceeds the length.
Larva – up to 25 mm, brown-yellow, with a forked rear end; each process has two teeth directed to the middle of the notch, the notch between the teeth is rounded.
Beetles winter in the soil at a depth of 10 – 12 cm, and larvae of different ages – at a depth of 5 – 35 cm. Beetles come to the soil surface from the second half of April, during the sowing of early spring and sugar beets. The timing of the appearance of adults in the forest-steppe zone for several years ranged from April 12 to 25, the mass years and mating – from April 27 to May 12.
In spring, beetles feed on pollen and dandelion flowers.
Eggs are laid in the soil in heaps of 3-5, in one clutch of 12 to 20 eggs; female fertility – from 200 to 500 eggs. Embryonic development lasts two to three weeks. Larvae of the first age are colorless, almost transparent, up to 2 mm, are born at the end of May – in June. They feed on small invertebrates, as well as shoots of weeds and cultivated plants. Larvae develop for 2–3 years, but some of them are up to 4 years old. Having completed development, the larvae burrow in September – October. The duration of pupal development is 3-4 weeks.