Beggar cleone (Conorhynchus mendicus)
Identification :
- The mendicant cleone is a beetle belonging to the Curculionidae family.
- Adult has a length of 12 to 17 mm.
- It is covered with small gray scales which hide the black color of the seed coat.
- The egg has a diameter of 1 mm and is light orange in color.
- The last instar larva is 13 mm long with a whitish color.
Biology :
The beggar clone attacks the sugar beet. It also lives on wild Chenopodiaceae.
Under Moroccan conditions this pest has only one generation.
The adult overwinters hidden in the soil of beet fields after harvesting without feeding.
The female lays her eggs near her host plant.
The eggs hatch after a period of 10 days.
After hatching, the larvae spend about 6 to 7 weeks development time depending on weather conditions.
Pupation takes place in the soil in small earthy hulls.
Symptoms :
- The adults cause serious damage in beet fields by attacking seedlings.
- By devouring the young plants, the adults force the farmers to reseed their plots.
- The larvae burrow the root perpendicular to the axis of the taproot, which hinders its development.
- The larvae gradually sink into the soil along the pivot, which they gnaw first superficially, then deeper, making characteristic excavations.
- The deep galleries on the roots cause their drying out and consequently the death of the whole plant.
Control :
- Chemical control using AVAUNT 150EC at a rate of 250 ml / ha.
