The sugar beet weevil Cleonus punctiventris GERMAR
1993
Zsemberi, S. | Pets, G.
The sugar beet weevils overwinter in 90-95 as adults 20-40 cm deep in the soil. 5-10 of the larvae may overwinter and come out only in the second year. When soil temperature reaches 6-7 degrees (in early April) the beetles start to migrate to the surface and begin their damage. They feed on the cotyledons of the young beets. Later they damage the leaves of the young plants. After a few weeks of maturation nourishment they lay their eggs by the stem of young plants. The bone white grubs with brown head and without feet hatch after two weeks. First they make shallow furrows on the surface of sugar beet roots, later they make deeper holes. The mature grubs are transformed into imagoes in September in 20-40 cm depth and overwinter at the same place. In spring, when the temperature is above 10 degrees they start to migrate on foot at a speed of 300 m/day. When the temperature rises above 16 degrees they start to fly and they can reach beet fields several kilometres away. The migration of sugar beet weevil can be prevented by digging a ditch around the beet field and putting Thimet or other insecticide in the ditch. The dressing of the seeds is also very effective. Promet (furatiocarb), Force (telfutrin), Furadan 4 F (karbofuran) can be used. In vegetation Azodrin 40 WSP, Bancol 50 WP, Padan 50 SP or Methilparathion are advised
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