Pests and Diseases
Croton caterpillar (Achaea janata)
Several noni croton caterpillars feeding on a noni seedling.
| Pest: Croton caterpillar
Damage: Croton caterpillars
feed on leaves of noni seedlings. The caterpillars can consume
most of the foliage, leaving large gaping holes in the leaves
with just the veins and petioles remaining.
This moth is widespread throughout the tropical and subtropical
Pacific, in Australia, and the Orient and has a wide host range.
It was first collected in Hawaii in 1944 and is now present
on all major islands. The croton caterpillar was first observed
on noni in the Hilo, Hawaii in 2002.
The croton caterpillar feeds on many different species of plants.
Castor bean and croton are preferred hosts. Occasional hosts
include banana, cabbage, Chinese cabbage, crown of thorns, Ficus,
macadamia, mustard, poinsettia, rose, sugarcane and tomato as
well as some legumes, teas, Brassica species and noni.
- Biological control (natural enemies).
- Grow seedlings on elevated benches and increase plant
spacing in nurseries to eliminate hiding places for the
- Use of pyrethroid insecticides.
- Hand-picking and destruction of caterpillars.
| Notes: Noni stem canker
has not been previously reported to occur in Hawaii or elsewhere
in the world.