author(s)
Ogban EI, Oparaeke AM, Odey PO and Udeme Umo O

abstract
Plant powders prepared from three tropical plant species: Platycerium stemaria (P. Beauv.) Desv., Andrographis paniculata (Burm Fil.) Nes – GBIF and Oleandra distenta Kunze were tested in the laboratory under constant conditions at 30±2 °C and 60 – 65% r. h. for their ability to protect Bambara groundnut against Callosobruchus subinnotatus Fabricus in storage. Three levels of treatment concentrations, 0, 10 and 20 g per 150 g of Bambara groundnut were applied for evaluation of adult weevil mortality, suppression of egg laying and weight loss of Bambara groundnut due to C. subinnotatus attack. Treated and untreated Bambara groundnut seeds were infested with C. subinnotatus under prevailing storage conditions and replicated three times using Completely Randomized Design (CRD). The results showed that both P. stemaria and O. distenta leaf powders at 20 g per 150 g seeds of groundnut caused higher mortalities of adult C. subinnotatus at 24, 48 and 72 hours respectively. O. distenta at same concentration of 20 g per 150 g seeds evoked greater inhibition of C. subinnotatus egg laying for 8 weeks of treatment. However, the lowest percentage weight loss of Bambara groundnut was evoked by O. distenta at 20 g per150 g seeds. The efficacy of the powders on the beetles was dose-dependent with higher doses providing greater protection of the Bambara groundnut. This research proved that the plant powders were effective in killing the insect pests and protecting the seeds, and could therefore be recommended for stored products pest management programmes.