Symptoms of damage

• The eggs are laid on leaves.
• After hatching from the egg yellowish maggots bore the nearest vein of the leaf.
• The maggot then reach the stem through petiole and bore down the stem.
• If the infected stem is opened by splitting, distinct zig zag reddish tunnel can be seen with maggot or pupae inside it.
• The maggots feed on cortical layers of the stem, may extend to tap root, killing of the plant.

Identification of the pest

• Maggot: White in colour and remains inside the stem.
• Adult:  Flies are shining black and about 2 mm long.