Scientific name: Delia arambourgi (Seguy)
Common name: Barley Fly
Synonyms: Hyelemya arambourgi Seguy
Main hosts: Barley
Alternative hosts: Maize, Wheat, Bulrush millet, Tef, Some grasses
IMPORTANCE IN ETHIOPIA:
Major pest of: Barley, Tef
Minor pest of: Wheat
The larva feeds on the stem of the central shoot. The central shoot turns brown, dies, and may be easily pulled out of the plant. This typical shoot borer damage is called a “dead heart”. One larvae may destroy three or four shoots. In years of high infestation this pest can cause 40-50% reduction or total failure of the crop if rainfall is low.
INSECT BIOLOGY & RECOGNITION:
Egg: Usually the eggs are laid on the soil within a few cm distance of the plant. Sometimes they are found on the tips of the leaves. They hatch after 3-4 days.
Larva: The young larvae climb the plant to just above the first leaf sheaths. Then they bore through the tissue to the growing point. This results in the death of the central shoot (“dead heart”). After the second molt the larva attacks another shoot of the same plant or of another plant by eating through the leaf sheaths. Before reaching maturity at about 12 days after hatching, the larva moves to 3 or 4 shoots. When mature the white larva (maggot) is about 5 mm long.
Pupa: Pupation takes place in the soil near the roots of the plant. The pupal period is about 7 days.
Adult: The adult is a medium sized fly of about 7-8 mm length. It looks rather like a small house fly. The grey female has a pointed abdomen. The male is blackish and has a rounded abdomen.
Use resistant varieties when available