Dorcadion beetle

Systematic position of the Dorcadion genus belongs to the order Coleoptera and the family Cerambycidae (longhorn beetles). These insects are typical steppe-dwelling beetles that live primarily on the ground. Most adult beetles are flightless, as their elytra are often fused, which significantly limits their dispersal to active crawling across the soil surface.

Crops damaged by this pest primarily include various cereal grains. Agronomists often encounter them in winter and spring wheat, barley, rye, and several species of wild grasses. The larvae of this longhorn beetle reside directly within the soil, where they actively feed on the root systems and subterranean parts of stems, making them particularly destructive during the early spring growth phase.

Biology and life cycle of these beetles are characterized by a prolonged development, usually lasting one or two years. Adult beetles emerge onto the soil surface in the spring to mate and lay eggs in the topsoil layers. Upon hatching, the larvae move deeper into the soil profile to feed, where they complete their development, often causing significant stress to host plants by severing nutrient uptake pathways.

Damage and pest impact are evident in the stunted growth and sudden wilting of cereal crops. Due to the destruction of the root system, young plants turn yellow, wither, and frequently die in localized patches. The impact of Dorcadion is particularly severe during dry seasons, when compromised plants cannot recover from root feeding, ultimately leading to thin stands and substantial yield losses.

Protection measures involve a combination of agrotechnical strategies designed to reduce the population density of the pest:

• Deep autumn plowing to expose and eliminate larvae and pupae within the soil.
• Crop rotation that excludes primary host cereals to disrupt the life cycle.
• Effective weed control in the off-season to eliminate alternative food sources for the larvae.
• Application of authorized soil-applied or systemic insecticides if population thresholds are exceeded during the adult emergence period.