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Neem (Azadirachta indica) products were effective in protecting stored cowpeas against bruchid damage for over 4 months under artificial infestation in the laboratory. This practice, part of an extension package, is becoming popular with farmers. In field trials, aqueous neem seed extracts, as well as leaf extracts reduced thrips (Megalurothrips sjostedti), incidence in cowpeas and increased yields significantly. Extracts also had an adverse effect on the biology of the pod borer (Maruca testulalis). These findings have generated interest in a neem-based pest management system for cowpeas and possibly other crops.

Azadirachtin, applied topically to final instar larvae of the African armyworm (Spodoptera exempta, Walker) (Lepidoptera: Noctuidae), adversely affected oogenesis and reproductive maturation in subsequent female moths. Moths obtained from such treated larvae failed to mature their oocytes, probably as a result of interference of azadirachtin with vitellogenin synthesis and/or its uptake by developing oocytes. Such larval treatment also caused substantial decreases in fecundity and although fertility in affected females was not decreased significantly, emerging larvae were less viable, less than 40 ~o reaching the fourth instar.Closer examination revealed that protein levels as well as fat body development in female moths were suppressed by azadirachtin. Prospects for field control of this pest with neem are discussed in the light of these findings.

Studies were conducted between 1994 and 1995 in the northern savanna zone of Ghana on farmers' perceptions of insect pests of millet using a checklist in semi-structured interviews. Such information is essential for priority setting and also for the generation of technologies that meet farmer aspirations and are thus likely to be adopted by them. Farmers identified millet insects and diseases as the second most important production constraint after low soil fertility. Head feeders and stem borers were regarded as important pests of millet. Farmers generally relied on natural control for field pests but in storage, sundrying infested produce was mentioned as a control measure adopted by many farmers. Yield loss studies showed that insect pests can contribute to over 50% yield reduction under field conditions.

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