Otiorhynchus rugifrons

Taxonomic position: Otiorhynchus rugifrons belongs to the order Coleoptera and the family Curculionidae (true weevils). It is a significant root-feeding pest known for its resilience and ability to establish populations in various environmental conditions across Europe and other regions.

Host plants: This species is a polyphagous pest, meaning it feeds on a wide range of botanical families. Primary hosts include strawberries, raspberries, blackberries, and roses. It also frequently attacks nursery stock, including various ornamental shrubs and conifers, causing significant financial losses in the horticultural sector.

Biology and life cycle: The life cycle involves both soil-dwelling larvae and foliage-feeding adults. Adult weevils are flightless and strictly nocturnal. They deposit eggs in the soil near the root zone during the summer months. Overwintering occurs primarily in the larval stage deep in the soil, which allows them to survive harsh winter conditions and emerge to feed as adults in late spring.

Damage and pest status: Larval feeding is the most destructive phase, as they consume root hairs and primary roots, often severing the connection between the plant and the soil. This leads to wilting, stunted growth, and eventual plant death. Adult damage is characterized by notched leaf edges, which, while less lethal, significantly weakens the plant and decreases its aesthetic and commercial value.

Control measures: Management of Otiorhynchus rugifrons requires an integrated pest management (IPM) approach. Cultural practices like keeping soil moisture levels consistent and ensuring good drainage can reduce larval survival. Chemical control involves targeting adults with contact or systemic insecticides during their nocturnal feeding period. Biological control using entomopathogenic nematodes (such as Heterorhabditis or Steinernema species) has proven highly effective for soil-based larval control.

• Regular monitoring using pitfall traps.
• Thorough removal of debris and weed control.
• Application of biological nematodes.
• Rotation of crops where applicable.