Sainfoin clearwing

The Sainfoin clearwing (Bembecia scopigera) is a moth belonging to the family Sesiidae and the order Lepidoptera. This species is specifically recognized as an agricultural pest that focuses its developmental cycle on leguminous plants, particularly sainfoin (Onobrychis).

The pest causes significant damage to sainfoin crops by infesting the root system and the base of the stems. Larvae bore galleries inside the roots, which disrupts the transport of water and nutrients, eventually causing the plant to weaken and wither during periods of drought or high stress.

The biological cycle of this insect is annual. Adult moths emerge during the summer months, seeking out suitable host plants to lay their eggs near the root collar. Upon hatching, the larvae immediately tunnel into the root, where they remain throughout the winter, feeding and developing until they pupate the following spring.

The damage caused by Bembecia scopigera is often insidious because the larvae are hidden inside the plant tissues. As the root system becomes riddled with tunnels, the plants lose their ability to regrow efficiently after cutting. Furthermore, damaged roots become highly susceptible to soil-borne pathogens and decay.

Effective management strategies focus on cultural control techniques to break the insect's life cycle.

• Implementing crop rotation cycles to starve the larval populations.
• Deep plowing of exhausted fields to destroy overwintering pupae.
• Maintaining field hygiene and removing infected plant residues immediately after harvesting the final cut.