Black vine weevil

The Black vine weevil (Cheiracus sulcatus, synonym Otiorhynchus sulcatus) is a significant agricultural and horticultural pest classified within the Curculionidae family of the order Coleoptera. This species is widely known for its destructive feeding habits, affecting a broad range of ornamental and edible plant species across temperate regions worldwide.

This pest infests diverse crops, notably strawberries, grapevines, yew, rhododendrons, and various greenhouse flowering plants such as primroses and cyclamen. Due to its polyphagous nature, it thrives in nurseries and gardens, often causing severe economic losses by attacking both underground roots and aerial foliage throughout the growing season.

The life cycle of the insect consists of eggs, larvae, pupae, and adults. Adults are nocturnal, typically sheltering in soil or under debris during the day. The larvae, which are the most destructive stage, spend their time underground feeding on root tissues. They overwinter in the soil and resume their feeding activity as soon as soil temperatures rise in the spring.

Damage is twofold: adult beetles cause notched leaf edges, which is mostly cosmetic, while the larvae destroy root systems, preventing water and nutrient uptake. Infected plants exhibit symptoms like stunting, yellowing (chlorosis), wilting, and sudden death. In many cases, by the time symptoms are visible on the foliage, the root system is already extensively compromised.

Effective management requires an integrated approach. Biological control using entomopathogenic nematodes (such as Heterorhabditis or Steinernema species) is highly effective when applied to moist, warm soil. Additionally, sanitation practices, such as clearing debris and soil cultivation, help reduce habitats for adults. For severe infestations, targeted chemical applications applied at night can suppress the adult population.