Pacific Pests, Pathogens and Weeds

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Summary

• Worldwide distribution. Not recorded in Oceania. On shallot, onion and relatives, food legumes, and potato and cabbage families. Usually, a minor pest in Pacific islands.
• Young caterpillars scrape the surface of outside leaves; larger ones make holes and eat all the leaves.
• Eggs hatch and larvae stay together at first then fan out until there is only one per plant. They pupate in the soil, producing a moth that is a strong flyer.
• Cultural control: handpick; grow under nets; mass trapping using lights; weed; 1-2-year crop rotations.
• Chemical control: PDPs: chillies, neem, pyrethrum, or derris; or, if grown for sale, Bt (Bacillus thuringiensis) on young caterpillars.