COMMON NAMESRice moth (English); onhuko (Oshiwambo - it is often specified whether Corcyra is in grains or flour); onufi (Oshimbalantu)Note: Many farmers and extension staff refer to the Corcyra cephalonica attacks as “weevils” but it is actually a moth. Weevils have not yet been found in pearl millet or sorghum grains. PEST STATUSC. cephalonica is a major pest of stored grains of pearl millet (Pennisetum glaucum) and sorghum. Considering the long storage period of pearl millet, which may be several years, C. cephalonica may be the most important pest of millet in Namibia. Infestation has been noticed in pearl millet flour as well, although the flour is seldom stored long enough to become infested. C. cephalonica is widely distributed in all four regions in north central Namibia.DESCRIPTIONThe caterpillar of Corcyra is up to 15 mm long and white or cream in colour. The body is covered with fine hairs. Caterpillars are usually hidden in the frass and webbing between the grains.The adult moth is grey, often with darker patterns on the wings. The wingspan is 20-23 mm. The moth is usually seen in large numbers on walls, poles or containers where grains are stored. Infested grains are spun together in a tight web and white caterpillars and cocoons are found in the grain. The caterpillars produce a lot of dung (frass), which can then be infested by other storage pests such as flour beetles. CONTROLA few local control methods are used by farmers. Unconfirmed reports from Omafo in the Ohangwena region, indicate that some farmers use leaves from a local tree which are placed on top of the stored grains before sealing the storage basket. More information about this method is needed.Farmers often try to clean infested grain by the use of sieves, but when the infestation is too severe the damaged grain is used for chicken feed. Try to avoid using chemicals in stored food. If chemical control is still considered necessary, please contact the FSRE pest officers for precise advice on chemical control. The contact numbers and addresses are listed on the cover. OTHER NOTESTrials to improve storage of pearl millet were started in north central Namibia during 1998. A joint team from Natural Resources Institute (UK), the Directorate of Research and Training and the Directorate of Extension and Engineering Services is testing cheap and safe methods to protect stored pearl millet, for example by comparing the pest infestation in traditional storage baskets to traditional baskets lined with a cheap plastic membrane and the use of metal water tanks.
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