Bishop's mitre

The bishop's mitre (Aelia acuminata) is a member of the Hemiptera order and the Pentatomidae family. This shield bug is a well-known agricultural pest that specializes in damaging cereal crops, often found in fields throughout Europe, parts of Asia, and North Africa.

Primary host plants include winter and spring wheat, barley, rye, and oats. In addition to agricultural crops, this species thrives on wild grasses, which act as alternative hosts that allow the population to survive during the off-season or in non-cultivated field margins.

The biology of the species involves overwintering as adults in leaf litter, debris, or near forest shelterbelts. When spring temperatures rise, the bugs migrate to cereal fields. They feed on plant sap, mate, and deposit eggs on the leaves. The nymphs undergo five instars before reaching maturity, with the life cycle synchronized with the development stages of the host plants.

Damage is caused by both adults and nymphs piercing the plant tissues and extracting sap. The most critical damage occurs when the pest attacks the developing spikes and grains. This results in reduced grain weight, shriveled kernels, and a significant decline in the nutritional and technological quality of the harvest, impacting yield consistency.

Integrated Pest Management (IPM) is essential for effective control. Key strategies include:

• Maintaining crop rotation to break the pest cycle.
• Removing weeds and crop residues from field borders to minimize overwintering sites.
• Monitoring population density during the booting and heading stages.
• Applying selective insecticides when the number of bugs exceeds established economic thresholds.

Timely field inspections are crucial for assessing the threat level before the milk-ripe stage of the grain. Using biological control agents and promoting natural predators are also being explored as sustainable alternatives to chemical pesticide applications.