Photo 1. Caterpillar damage on onion leaves caused by Spodoptera sp. Often the caterpillars are found inside the tubular leaves.
Photo 2. Egg mass of Spodoptera exugia. Note the hairs over the eggs taken from the abdomen of the female.
Photo 3. Late stage caterpillar, Spodoptera exugia. Note the lines along the side of the body and the one along the back.
Common cutworm, beet armyworm. Note that the species on onion has not been identified in Pacific islands where damage to shallots has been seen. In this fact sheet, it is assumed to be Spodoptera exigua. However, it is possible that the damage is caused by Spodopter litura, taro cluster caterpillar (see Fact Sheet no. 31).
Spodoptera spp. The common species on onion in other parts of the world is Spodoptera exigua (common or beet armyworm); however, this has not been identified in Pacific island countries, and the species attacking onion is likely to be Spodoptera litura.
AUTHOR Grahame Jackson
Photo 1 Ooi P (Image ID 38351). Photos 2-5 Spodoptera exigua (Koppert Biological Systems).
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.
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