Cabbage stem weevil

The cabbage stem weevil (Ceutorhynchus granulicollis) is a member of the Curculionidae family within the Coleoptera order. This species is a significant pest of brassica crops, causing economic losses in agricultural regions where rapeseed, mustard, and cabbage are grown on a large scale.

The primary hosts of this weevil include various species within the Brassicaceae family, particularly winter and spring oilseed rape. Adults cause damage by feeding on leaves, but the most severe impact comes from the larvae, which burrow into the host plant's tissues.

The biological cycle of this pest begins with adults overwintering in the soil or protected areas. In the spring, they emerge and start feeding on young plants. Females then lay eggs inside the stems or petioles of the plants, where the larvae hatch and proceed to feed internally for several weeks.

The larvae create tunnels within the stems, which leads to physical damage, wilting, and distorted growth of the affected plants. This structural damage weakens the plant's vascular system, often resulting in premature ripening, reduced yield, and a higher susceptibility to secondary fungal diseases.

• Crop rotation to break the pest's life cycle
• Timely removal of cruciferous weeds that act as hosts
• Monitoring adult activity using yellow traps in early spring
• Applying insecticides before egg-laying occurs

Controlling Ceutorhynchus granulicollis requires proactive field management. Because the larvae are protected inside the stem, insecticide applications are most effective against adult beetles during their migration to the crop and before the females begin the egg-laying process.