Wheat bulb fly
Delia coarctata

A small fly which lays its eggs in exposed soil in July and August. These eggs hatch from January to March the following year, depending on soil temperatures. Once hatched the larvae move through the soil and bore into the base of cereal plants feeding on the central shoot. This causes the characteristic dead-heart symptoms to appear. Although the outer leaves remain green during early stages of attack plants become dull in appearance and, unless examined carefully, the attack may go unnoticed until dead-hearts become visible in February or March.