Major pests of Croton are:-
1.Croton Mealy bug: Planococcus lilacinus
Symptom of damage:
- Infestation – underside of leaves, the base of petioles and nodes of tender shoots.
- Infested plants give the withering appearance.
Identification of the pest:
- The body of the scale is covered with white wax like mealy substance.
- Small, soft-bodied insects.
- Female is wingless, oval body clothed with white threads.
Management:
- Maintain adequate shade
- Destroy nets of red ants and cocktailed ant
- Dust Quinolphos 1.5% or methyl parathion 2% or malathion 5%
- Spray the affected patches with Quinolphos 25 EC 2ml per lit of water.
- Conserve natural enemies like predatory ladybird beetle, Cryptolaemus montrouzieri parasitoid Leptomastix dactylopii.
2.Croton Brown scale: Saissetia coffeae
Symptom of damage:
- Feed from the underside of the leaves along the midribs.
- Affected plants lose their vigour and the leaves dry off.
Identification of the pest:
- Nymphs – yellow, greenish-brown or dark pink, flat and oval.
- “H” shaped yellow mark (Half-grown scales)
- Adult – Female is a hemispherical, body is covered by a brown hard shield.
Management:
- Control ants as in the case of mealy bugs.
- Remove and burn weeds which harbour the scale.
- quinolphos 25 EC 2ml per lit of water.
3.Croton caterpillar: Achaea janata
Symptom of damage:
- Caterpillars feed on the foliage
- Denuding the leaves leaving veins and petioles
Management:
- Hand picking & destruction
- Grow seedling on elevated benches
- Increase plant spacing in nurseries
- Spray malathion or quinalphos at 2ml/lit of water
Source-
- TamilNadu Agritech Portal
