4. Castor capsule borer

4. Castor capsule borer - Dichocrosis (= Conogethes) punctiferalis Guen. (Pyraustidae : Lepidoptera)

    Damage
    • The larva borers into the central core of the pseudostems resulting in the death of the central spindle causing charactersic “dead heart” symptom.
    • In the case of capsules, the caterpillars bore into the immature capsules and feed on the seeds rendering them empty.
    • The caterpillars occasionally tunnel into the panicle also. A characteristic indication for the presence of the larvae is the oozing out of excreted frass materials at the mouth of the bore hole, which are very conspicuous on the stem or pods.
    Bionomics
    • The adult is a medium sized brownish yellow coloured moth with a number of dark spots on the wings.
    • It lays eggs on the top leaf axils of young pseudostem.
    • The larva bore into the tender parts of the panicle, flower buds and immature capsules only, the later stage larva bore into the stem.
    • The full grown larva is measuring 15-25 mm long and it pupates within the larval tunnel inside the pseudostems.
    • The life cycle is completed within 25-40 days.
    Management
    • Collect and destroy the affected plant parts.
    • Destroy the alternate host plants from the vicinity of the plantation
    • Spray phosalone 3 ml/litre or Dimethoate 0.03 % /litre or quinolphos 4 ml/litre or fenthion 1.25ml / litre of water.

Last modified: Tuesday, 26 June 2012, 6:26 AM