- Worldwide distribution. Members of the cabbage (brassica) family, e.g., head cabbage, Chinese cabbage, radish, cauliflower and broccoli; Amaranthus and watercress. An important pest.
- Eggs, yellow, small, laid singly. Young larvae mine leaves; larger ones leave waxy windows and holes. If touched, larger ones wiggle backwards, and fall down on silk threads.
- Natural enemies: wasp parasitoids, especially Cotesia (see Fact Sheet no. 287) and Diadegma (see Fact Sheet no. 285).
- Cultural control: inspect nurseries and crops regularly; remove larvae; use trap crops, e.g., mustards or Chinese cabbage (Bok Choy), but destroy trap crop before eggs hatch.
- Chemical control: in household plots, PDPs (chillies, neem, derris, pyrethrum to safeguard natural enemies); in commercial plots, grow under nets; use Bt (Bacillus thuringiensis) sprays against caterpillars when young. Avoid pyrethroids and organophosphates.
Pacific Pests, Pathogens, Weeds & Pesticides
Cabbage diamondback moth (020)
Photo 1. Young caterpillars of diamondback moth, Plutella xylostella, eat from the underside of the leaf to the top layer of wax.
AUTHORS Grahame Jackson & Mike Furlong
Information from CABI (2019) Plutella xylostella (diamondback moth). Crop Protection Compendium; and from Walker K (2007) diamondback moth (Plutella xylostella): PaDIL - http://www.padil.gov.au; and Diamondback moth (2021) AgricultureVictoria, Australia. (https://agriculture.vic.gov.au/biosecurity/pest-insects-and-mites/priority-pest-insects-and-mites/diamondback-moth); and Diamondback moth Plutella xylostella. Cesar Australia and South Australian Research and Development Institute. (https://cesaraustralia.com/pestnotes/caterpillars/diamondback-moth/); and Diamonback moth: cabbage in Indonesia and Western Australia (2020) Agriculture and Food. Department of Primary Industries and Regional Development. Government of Western Australia. (https://www.agric.wa.gov.au/broccoli/diamondback-moth-cabbage-pest-indonesia-and-western-australia); and from Mike Furlong (pers. comm.), University of Queensland, Australia. Photos 1&2 Graham Walker, Plant and Food Research, Auckland, New Zealand. Photo 4 Richard Markham, ACIAR, Canberra. Photo 4 Jack Kelly Clark, US Statewide IPM Project. Photos 5,7-9) Mike Furlong, University of Queensland, Australia. Photo 6 Mani Mua, SPC, Sigatoka Research Station, Fiji.
Produced with support from the Australian Centre for International Agricultural Research under project PC/2010/090: Strengthening integrated crop management research in the Pacific Islands in support of sustainable intensification of high-value crop production, implemented by the University of Queensland and the Secretariat of the Pacific Community.