Note: Bruchid beetles cannot be recognised on the pattern on their shell alone and many species occur in Namibia. For practical purposes, they are all treated as one species " Cowpea bruchid", until more information is available. COMMON NAMESonhuko yomakunde (Oshikwanyama); ontuko yomakunde (all others)PEST STATUSBruchids are major pests on cowpea (Vigna unguiculata) in north central Namibia. They may be the main constraint to increased cowpea production in the area. Bruchids have been found on cowpea grains and beans, and the same (or a similar) bruchid was reared from a dried maize cob.Cowpea bruchids have been found all over north central Namibia, wherever cowpeas are stored. DESCRIPTIONCowpea bruchids are small beetles, 2-3 mm long. They are mainly found on cowpea grains in storage. Damaged grains are full of small holes and dead beetles may be found inside the grains.The white eggs are glued to the outside of cowpea grains and are clearly visible as small white dots on the grain. Damage is restricted to eating quality only. It is not possible to eat (or sell) the cowpea grains when they are riddled with bruchid holes. Germination of cowpea is not affected, however, and even seeds that are full of holes will germinate very well during the next season. CONTROLFarmers often mix cowpea grains with ash. This method is still recommended as a cheap and safe control method. To be efficient, one should use at least 5 % of ash.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. PREDATORSIn Namibia, a tiny flying insect is often hatched from cowpea grains that are infested with bruchids. It may be a parasite on bruchids, but has not yet been identified.
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