<div class="WordSection1"><p>A laboratory study was carried out to examine the efficacy of solvent extract of <em>Eucalyptus globulus</em> leaves in reducing post-harvest losses caused by cowpea weevil<em> </em>(<em>Callosobruchus maculatus</em>) on cowpea seed variety RSH 256. 450 g of <em>E. globulus </em>leaf powder were put in 1000 ml flask and 450 ml of n-hexane was used as the solvent. The extract was tested at dosages of 50, 100 and 150 µl 50 g^-1 of cowpea grains on the weevil in stored cowpea. The different rates of treatment recorded significant differences (<em>p</em> &lt; 0.05) in causing adult mortality compared to the untreated control. The different rates of treatment also recorded significant differences (<em>p</em> &lt; 0.05) in emergence of F1 adults of each treatment compared to the control. The percentage masst loss and grain damage were also suppressed as a result of treatment with the plant material compared to the untreated control. However, among the treatments 150 µl 150 g^-1 cowpea recorded the highest adult mortality rate and lowest emergence while control had the lowest mortality rate and the highest emergence of the insect. The rates of application were indicative of bioactive characteristics of the plant extract.<strong></strong></p></div>

Licensed under a Creative Commons Attribution 4.0 International License A laboratory study was carried out to evaluate the efficacy of cashew nut shell extract in the control of cowpea bruchid, Callosobruchus maculatus (Fab.) under prevailing laboratory conditions. Fresh ethanolic and stored extract of cashew nut shell served as treatments which were compared with untreated control. Data collected on adult mortality, total number of emerged progeny (adults), number and weight of damaged seeds (seeds with holes) and undamaged seeds (seeds without holes) and percentage seed weight loss, and average number of seeds per 50 g in a container and the data were subjected to a two-way analysis of variance and significant different means were separated using Duncan`s Multiple Range test (DMRT) at 5% level of significance. The results revealed that treated plants generally performed better than the untreated. The different rates of treatment recorded significant differences (P <0.05) in causing adult mortality compared to the untreated control. The different rates of treatment also recorded significant differences (P <0.05) in emergence of F1 adults of each treatment compared to the control. It was also noted that the extract reduced or suppressed the weight loss and grain damage as a result of treatment with the extract compared to the untreated control. However, freshly extract of cashew nut shell recorded the highest adult mortality rate and lowest emergence while control had the lowest mortality rate and highest emergence of the insect. The rates of application were indicative of bioactive characteristics of the extract.

A field study was carried out to assess the efficacy of some botanicals in the control of field insect pests of Amaranthus hybridus. Dry leaf and bark ash extract of Azadirachta indica served as treatments which were compared with Lambdacyhalothrin and a control. The experiment was fitted into a randomized complete block design with three replications. Data collected were subjected to a two-way analysis of variance and significant different means were separated using Fishers Least Significant Difference (LSD) test at 5 % level of probability. The results revealed that treated plants generally performed better than the untreated plants as they were taller, had more leaves, branches, wider stem girths and gave higher fruit yield. bark ash extract of Azadirachta indica performed better in most parameters measured. The results indicate that leaf and bark ash extract of Azadirachta indica if properly harnessed can be used as a biopesticide in the control of field insect pest of A. hybridus.

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Groundnut production has been reported to be threatened by storage insect pests which caused significant damage in storage. The repellent and efficacy activities of Citrus sinensis leaf extract were assessed on Trogoderma granarium in stored groundnut. The treatment was laid in a Completely Randomized Design with 3, 5, and 7% concentration level of methanolic and petroleum ether Extract for insecticidal activities. The results of C. sinensis leaf extract toxicity obtained was significant at 7% concentration at 24, 48 and 72 hours after treatment with 100% and 80% mortality in methanolic and Pet. ether extracts respectively in adults. Half disc experiment was carried out to determine the repellency activities with 1, 2, and 3% concentration of methanolic and pet. ether extract. It was observed that at 2HAT the insects moved towards the extract with the Index of Repellency of 1.13 at 3 % concentration for methanolic and pet ether extract, as the hours increase from 4 to 6HAT it was observed that the extract acted as repellant towards the insect with methanol and petroleum ether extract of 3 % concentration having the highest repellency index of 0.47. Petroleum ether at 1 % concentration with the value of 1.47, 1.40 and 1.20 repellency index across the 2, 4 and 6HAT showed that the extract remains an attractant towards T. granarium. The results obtained from this study is an indication of the potential of methanolic and petroleum ether crude extract of C. sinensis in groundnut storage