Alfalfa seed chalcid

The Alfalfa seed chalcid (Bruchophagus mellipes) is a destructive pest belonging to the order Hymenoptera and the family Eurytomidae. This minute wasp specifically targets the reproductive structures of legume crops, posing a significant threat to global alfalfa seed production.

The primary host for this pest is alfalfa (Medicago sativa). The female wasps insert their ovipositors into the developing pods, laying eggs inside the seeds. The larvae develop entirely within the host seed, making it difficult to detect the infestation until the emergence of the adults.

Regarding its biological cycle, the pest typically overwinters as mature larvae inside infested seeds left on the field or in storage. Following pupation in the spring, adult wasps emerge and begin mating. The life cycle is tightly synchronized with the flowering and pod formation periods of the alfalfa crop.

The damage caused by Bruchophagus mellipes involves the complete consumption of the seed's interior. As larvae feed, they hollow out the seed, leaving only the outer shell. A characteristic sign of infestation is the presence of small, circular exit holes in the mature seeds, which significantly reduces seed viability and market value.

• Crop rotation to minimize the buildup of local pest populations.
• Timely harvesting to remove pods from the field before adult emergence.
• Sanitation, including the destruction of volunteer alfalfa and crop residues.
• Monitoring adult wasp activity with sweep nets during the pod-filling stage.
• Chemical control applications targeted during the peak period of adult oviposition.