The Rice Hispa (Dicladispa armigera)

 

The Rice Hispa (Dicladispa armigera)

Scientific Name:

    Dicladispa armigera

Order:

    Coleoptera

Family:

    Chrysomelidae (Hispinae)

Distribution:

    India, Pakistan. Bangladesh, Sri Lanka, Burma, Malaysia, Sumatra, Java, Cambodia, Thailand, Laos, Vietnam, South China, West Iran, Nepal, Indonesia, New Guinea and Philippines.

Host:

    Rice, sugarcane and various grass species.

    The larvae are legless, creamy-white and are not easily seen, because they are concealed inside the leaf tissue. The adults are small, shiny, blue-black beetles measuring 5 mm in length with spines on the thorax and elytra.

Life-cycle:

    The beetles start laying eggs in the leaf tissue towards the tip singly. A female may lay on an average 55 eggs and the eggs hatch out into flat yellowish grubs which mine into the leaves. They pupate in the leaf mines. The egg, larval and pupal periods occupy 4-5, 7-12 and 3-5 days, respectively. The insect passes through about six generations a year.

Damage:

    The beetle itself feeds on the green matter of the tender leaves producing the characteristic narrow white lines on them. The grubs mines into the leaf tissue and eat up the leaf content. The presence of these grubs in the leaf tissue is indicated by the peculiar blister spots towards the tip of the leaves. In case of severe attack, the leaves turn brown and wither away presenting a sickly white appearance. In India, especially in Andhra Pradesh, West Bengal and Bihar, it often assumes serious proportions on young paddy crop. The damage varies from 25-65 per cent.

Control:

1. Cut off tips of leaves harbouring the insects during early infestation and destroy them.
2. Spray 300 ml of methyl parathion 50 EC or 625 ml of fenitrothion 50 EC or 2.5 litres of lindane 20 EC, in 250 litres of water/ha. If the attack continues, repeat the spray after two weeks.