Nature of damage of the Gram pod borer (Helicoverpa armigera)

The pest is active through out the year but damage to gram is cause from November to March. The damage is caused by the larvae which feed on the leaves and destroy the seedlings in the early stages. At the time of pod formation it is found feeding on the developing grain after cutting a hole in the pod and thrusting its heads therein. It does not hide in the soil during day but remains hide in the plants. It has been estimated that a single caterpillar destroys 30-40 pods of gram in its life time. It has been observed that grown caterpillars feed on the small larvae of its own which is known as cannibelism. In severe infestation damage may be caused from 20-50 per cent.