Summer chafer

The Summer chafer (scientific name Amphimallon rufus) is a significant soil-dwelling pest belonging to the order Coleoptera and the family Scarabaeidae. These beetles are widely recognized for their destructive impact on various agricultural crops, nurseries, and managed grasslands throughout their European distribution range.

The life cycle of Amphimallon rufus consists of complete metamorphosis: egg, larva, pupa, and adult. The adult beetles are small, typically ranging in color from light to reddish-brown. While the adults feed on the foliage of trees and shrubs during the twilight hours, the primary agricultural threat is posed by the larval stage, which resides exclusively underground.

Larval development takes several years, during which the larvae pass through three instars. They are specialized root feeders, equipped with strong mandibles capable of consuming the fibrous and tap roots of various plants. Their growth is directly dependent on soil moisture and root availability, often leading to patchy crop establishment and significant losses in plant density.

The damage caused by the larvae is characterized by the sudden wilting and death of plants, as the destroyed root system can no longer supply necessary water and nutrients to the aerial parts. In heavily infested areas, patches of dead or stressed vegetation are a clear indicator. Young transplants and seedlings are particularly vulnerable and can be destroyed rapidly by the feeding activity of the grubs.

Effective management of the Summer chafer requires an integrated pest management (IPM) approach. Key strategies include:

• Mechanical cultivation of the soil to disturb larval habitats and expose them to predators;
• Crop rotation to break the pest's life cycle;
• Application of soil-applied insecticides specifically targeted at larval stages during peak activity;
• Utilization of entomopathogenic fungi as a biological control agent for sustainable management.