Study to evaluate the insecticidal efficacy of pyrethrum, Chrysanthemum cinerariifolium, relative to a synthetic insecticide (Cypermethrin 10 E. C) in the control of some field pests of groundnut was carried out at the Teaching and

Brown pepper (Piper guineense) seed powder, used for culinary and medicinal purposes, was evaluated in the laboratory with a conventional storage chemical, actellic 2% dust (Pirimiphos-methyl), as standard, to protect stored cowpea against the cowpea bruchid, Callosobruchus maculatus. Four rates of the seed powder were used (2.5, 5.0 and 10.0 g/100 g seed with a control, 0.0 g) while actellic dust was applied at 1.0, 2.0, 3.0 g/100 g seed and 0.0 g/100 g seed as control. Data on percentage mortality, oviposition, adult emergence and seed damage were collected over a six-month period. Weevil perforation indexes (WPI) were estimated with the seed damage data. All data were analysed for variance at P≤0.05. Actellic dust at the lowest dose inflicted adult mortality (90 – 100%) in the first 48 h after treatment and prevented oviposition (95 – 100%) in the first five months of storage compared to the control. The highest rate of Piper guineense application caused mortality of up to 90.0% in 48 h, reduced oviposition (70 – 80%), decreased adult emergence (15.90 to 28.40 insects) as against the control (104.7 – 272.7 insects) and reduced seed damage by 80 % with a WPI of between 33.3 and 10.0 %. Proximate analysis and germination tests indicated that the treatment materials increased the moisture and crude fibre content, decreased crude protein content but had no significant effect on the viability of stored seeds. Organoleptic tests demonstrated that treatment materials had no significant negative effect on taste, odour, texture, appearance and overall acceptability of cooked cowpea seeds after six months of storage. It can be safely concluded that the powdered form of P. guineense seed at the highest doses (5.0 and 10.0 g) gave significant protection of cowpea seeds against the cowpea bruchid, which compared favourably with actellic dust when applied topically.

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Neem (Azadirachtaindica A. Juss.) seed oil (NSO) is acclaimed to have some form of insecticidal action against more than 400 insect species in at least 10 to 13 orders. The main delimitating factor in the wide acceptance of this well tested plant as a storage pest bioinsecticide is its foul sulfurous smell and bitter taste which impinges on the acceptability and marketability of treated produce. To ameliorate this shortfall, therefore, an assessment of the potential of impregnating different storage materials; [plastic containers (PLC), Bagco bags (BCB), Black polyethylene bags (BPB), white polyethylene bags (WPB) and calico bags (CAB)], with NSO in the managementof Callosobruchus maculatus (F.) in stored Bambara seeds (Vigna subterranea L.), was conducted in the laboratory. The experiment was laid out in a 4 x 5 factorial arrangement fitted into a completely randomized design (CRD). Factor A represented four concentrations of NSO (0.00, 0.50, 1.00, 1.50 ml/ 100g seed), while factor B were the five different storage materials. The treatments were replicated four times Generally, seeds stored with impregnated storage materials recorded more bruchids mortality, reduced oviposition rate, decreased number of emerged insects (F1 and F2) and had less damaged seeds (and hence decreased weevil perforation index, WPI) than the control. Concentration performance was dose related though the highest (1.50 %) did not differ statistically (P=0.05) from the medium (1.00 %) concentration. Seeds stored in BPBs had the highest mortalities, but recorded the lowest in number of eggs oviposited, egg/seed ratio, F1, F2 and cumulative emergence, respectively. These results differed significantly (P=0.05) with the seeds stored in other materials. BPB stored seeds were also the least damaged with lowest exit holes/seed, seeds with holes and WPI, respectively. The performance of BPB was closely followed by seeds stored in WPBs in all the parameters tested. Conversely, seeds stored in BCBs recorded the lowest mortalities but the highest in all other parameters assessed. Other storage materials (PLC and CAB) had better storage quality than BCB materials. Impregnation of storage materials with NSO could be a better option to direct seed application with its attendant drawback. The use of NSO impregnated black polyethylene bags, within the scope of the storage materials screened, to control damage by C. maculatus in stored Bambara seeds, should be encouraged.

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Neem (Azadirachta indica A. Juss.) seed oil (NSO) is acclaimed to have some form of insecticidal action against more than 400 insect species in at least 10 to 13 orders. The main delimitating factor in the wide acceptance of this well tested plant as a storage pest bioinsecticide is its foul sulfurous smell and bitter taste which impinges on the acceptability and marketability of treated produce. To ameliorate this shortfall, therefore, an assessment of the potential of impregnating different storage materials; [plastic containers (PLC), Bagco bags (BCB), Black polyethylene bags (BPB), white polyethylene bags (WPB) and calico bags (CAB)], with NSO in the management of Callosobruchus maculatus (F.) in stored Bambara seeds (Vigna subterranea L.), was conducted in the laboratory. The experiment was laid out in a 4 x 5 factorial arrangement fitted into a completely randomized design (CRD). Factor A represented four concentrations of NSO (0.00, 0.50, 1.00, 1.50 ml/ 100g seed), while factor B were the five different storage materials. The treatments were replicated four times Generally, seeds stored with impregnated storage materials recorded more bruchids mortality, reduced oviposition rate, decreased number of emerged insects (F 1 and F 2 ) and had less damaged seeds (and hence decreased weevil perforation index, WPI) than the control. Concentration performance was dose related though the highest (1.50 %) did not differ statistically (P=0.05) from the medium (1.00 %) concentration. Seeds stored in BPBs had the highest mortalities, but recorded the lowest in number of eggs oviposited, egg/seed ratio, F 1 , F 2 and cumulative emergence, respectively. These results differed significantly (P=0.05) with the seeds stored in other materials. BPB stored seeds were also the least damaged with lowest exit holes/seed, seeds with holes and WPI, respectively. The performance of BPB was closely followed by seeds stored in WPBs in all the parameters tested. Conversely, seeds stored in BCBs recorded the lowest mortalities but the highest in all other parameters assessed. Other storage materials (PLC and CAB) had better storage quality than BCB materials. Impregnation of storage materials with NSO could be a better option to direct seed application with its attendant drawback. The use of NSO impregnated black polyethylene bags, within the scope of the storage materials screened, to control damage by C. maculatus in stored Bambara seeds, should be encouraged.

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