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Neem (Azadirachta indica) kernel powder (NKP) mixed 1:1 (weight basis) with some inert diluents (fine-sand, kaolin-dust, and saw-dust) were applied into the whorls of sorghum seedlings . Cost-benefit analysis shows that it was financially most beneficial to use NKP + fine-sand to control S. calamistis on sorghum in Nigerian Sudan savanna.

Post-harvest losses caused by Callosobruchus maculatus is a major constraint to cowpea production and the improper use of synthetic insecticides by most farmers have resulted in environmental, health hazards, and development of insecticide resistance in insects. This study evaluates the efficacy of solar heat treatment using double-layered black polypropylene sheets in suppressing the development of the cowpea bruchid eggs and the effect of the heat absorbed on the germination potential of cowpea seeds. Five pairs of 2 – 3-day old adult C. maculatus were allowed to oviposit for ten days on 50 g cowpea seeds in a glass jar in the laboratory before exposure to 24, 48, 72 and 96 h solar heat treatment regimes. Infested cowpea seeds but not exposed to solarization was set along with the treatments while uninfested cowpea seeds was also set along and used as part of the germinability test. The experiment was laid out in a completely randomized design and treatments were replicated four times. The results showed that there were no significant differences among the number of eggs laid by adult C. maculatus on the cowpea seeds before solar heat treatment. Solar heat treatment of the cowpea seed at 24 h achieved 100% egg mortality of C. maculatus thus preventing adult emergence. The effect of solarization on seed viability showed that there were no significant differences between the infested cowpea seeds exposed to different solar radiation regimes when compared to uninfested cowpea seeds – range; 74% – 99% germination. The results showed that 24 h solar heat exposure of cowpea seeds in double-layered black polypropylene sheets could be the thermal death point of C. maculatus eggs on the seeds in the study area.

Watermelon has been reported to be vulnerable to insect pest pressure throughout its growth stages with a resultant indiscriminate calendar-based insecticide application (of up to 25 sprays/season in the study area), with its attendant consequences. In order to recommend the crop growth period(s) to effect chemical control measures that will give better return on investment, field trials were set-up in the early- and late-cropping seasons of 2016 and 2017. Forty, 5m long x 8m wide plots were demarcated in randomized complete block design in 4 replications. Treatments were applications of 0.5% Cyper-diforce® (Cypermethrin 30g/L + Dimethoate 250g/L) at seedling, mid-vegetative, mid-flowering, mid-fruiting stages and their combinations. Unsprayed plots served as control. Pest and beneficial arthropod density, leaf injury, crop growth and yield data were collected and subjected to variance analysis and significantly different means were separated by SNK at 5% level of probability. Cost:benefit ratios of the various treatments was also computed. Findings indicate that, leaf-eating beetles had the highest impact on stand survival and yield. Insect pest density and damage generally decreased with increase in frequency of insecticide application and treatment differences were significant (p< 0.05) except in the case of A. gossypii in the late-sown crop of 2017. Plot sprayed at seedling + vegetative + fruiting stages gave the highest fruit yield and return on investment. It is therefore suggested that, for economic production of watermelon, the crop should not be sprayed during the flowering period.

Maize weevil, Sitophilus zeamais, whose management has largely been via traditional control practices, is a key pest of stored maize grains causing severe losses. This study explored the use of Nigerian Raw Diatomite (RD) in the management of the weevil. A 3-replicated split plot designed laboratory experiment was conducted for 6 months duration. The treatments were Raw Diatomite (RD) at the rate of 250, 500, 750 and 1000 mg/kg and a control (untreated) across four improved maize grain varieties. Data collected were on mortality, F1 progeny produced, grain weight damage, and loss. Data were analyzed with variance analysis and significantly different means were separated using Turkey Kramer HSD test at P<0.05. Results showed that the control had the least weevil mortality across the varieties throughout the periods of assessment. Highest weevil mortality was recorded with increase in dose rates of RD and progresses to 100% - largely at the 14th day post-treatment. Control recorded the highest weight loss and grain damage of 16.5% and 38.1%, respectively when compared to all the other treatment rates on the most tolerant variety (SAMMAZ 25). The study revealed that RD had a promising potential to substitute synthetic insecticides and can be incorporated into the integrated pest management strategy against maize weevil. We therefore suggest that further work be done to refine the Nigerian RD so as to standardize the most effective dosage application rate for management of insect pests of stored maize and other cereals. Keywords: Raw Diatomite, Sitophilus zeamais, Maize grain damage

Red pumpkin beetle (Aulacophora africana Weise) is an important defoliator and vector of pathogens to its numerous crop hosts. Control had largely been by synthetic insecticides with their attendant consequences on man and the environment thus necessitating scientific studies on environmental-friendly management strategies. The experiment was conducted in the Research Farm of Federal University Wukari in the month of May 2019 with the aim of evaluating the attractiveness of A. africana to Light-emitting diode (LED) and Incandescent Light bulb colours. Five colours (red, yellow, green, blue and white) were used for the study. Each colour light was properly projected on 2 metre vertical screen (made of white polyethene) placed one meter above the ground. A setup without bulb served as the control. The light traps were arranged in a completely randomized design (CRD) in 6 replicates and ran simultaneously for six hours (1800 to 2400hrs). The pumpkin beetles attracted were collected in tubs containing soapy water. A. africana collected were counted and recorded according to bulb type and colour. Samples were identified at the Insect Museum of Ahmadu Bello University, Zaria. Among the Incandescent bulbs, White colour was most attractive to A. africana (4.30±0.38) while red attracted the least (0.71±0.01). Among LED bulbs, Blue was most attractive (3.99±1.01) while Red also attracted the least (0.78±0.03). Overall, LED attracted more pumpkin beetles than Incandescent bulb even though Student Newman Keul’s test indicates that the difference between them was due to random variation (p = 0.16). Correlation and regression analyses indicated increase in insect attraction with increased light intensity. The results, therefore, suggest that white Incandescent or blue LED bulb colours can be incorporated into insecticidal light traps to suppress their population/attract them away from host plants or fixed into ordinary light traps to harvest the insect for scientific studies.

Article History Keywords Attractiveness Hexapod orders Incandescent Light colours Light-emitting diode (LED) Light trap Phototactic.Dearth of information on response of hexapod orders to light sources and colours informed this study. The study was conducted in Federal University Wukari, Nigeria in the month of May, 2019 to evaluate the attractiveness of hexapod orders to Lightemitting Diode (LED) and Incandescent bulb light colours. Daily sampling using fabricated light traps with 5 different colours (white, yellow, red, green and blued) for each bulb type in 6 replicates was done. A trap with no lighting source was the control. Hexapods collected were sorted into their respective orders. Of the overall 13 insect orders collected, LED bulbs attracted 11 while incandescent, 10. Even though, certain hexapod orders exhibited higher affinity to specific colours, statistical analysis revealed that of the 11 orders from LED, differences in the mean number of insects attracted among the bulb colours was significant (p<0.05) only in Coleoptera and Lepidoptera while for incandescent bulb colours, the mean number of insects attracted was significant for Coleoptera, Lepidoptera, Hemiptera, Hymenoptera, Orthoptera, Mantodea, Odonata and Homoptera. Insect orders generally had higher affinity to white and blue colours. LED bulb colours significantly attracted higher number of insects than their corresponding incandescent colours, except for white on which incandescent was more attractive (p>0.05). Overall, attractiveness to hexapod orders increases with rinsing light intensity and LED bulbs were found to be more attractive to hexapods than do incandescent bulbs. Therefore, LED bulbs of higher light intensity with colours around the blue/white spectrum show potential for use in manipulating hexapods for man's benefit. Contribution/Originality:This study discovers that hexapod orders are largely highly responsive positively to blue and white electric light of higher intensity. It also shows that, the LED bulbs were generally more attractive to the hexapod orders than the incandescent. This knowledge can be harnessed in manipulating the hexapods for man's benefit.

Harvester ants (Messor galla Forel) would defy various control strategies. Two field experiments were conducted to evaluate the effects of spent engine-oil and other naturebased materials on their emergence in Maiduguri, Borno State of Nigeria. The evaluated treatments are spot applications of spent engine-oil and some natural materials in experiment 1 and individual and equal mixture of pure neem seed kernel oil and spent engine-oil in experiment 2. Spot application of permethrin served as positive control. Experiment 1 results showed no significant difference (p>0.05) between permethrin and spent engine-oil (which was the most effective treatment). While neem seed oil was significantly (p<0.01) more effective than the untreated control, the result on the 28 th day after application showed no significant difference (p>0.05) in the population index of ants that emerged from nests treated with aqueous neem seed extract, salt/potash solution and extract of Eugenia aromatica fruit from those of the untreated control. Experiment 2 result showed no significant difference (p<0.05) between Permethrin, spent engine-oil, neem seed kernel oil and an equal mixture by volume of pure neem seed kernel oil and spent engineoil in suppressing the emergence of the ants. These were, however, significantly different (p>0.05) from the untreated control. While the result shows no significant difference between the insecticidal treatments, it was observed that equal mixture of spent engine-oil and neem seed kernel oil was the most effective, followed by spent engine-oil, permethrin and neem seed kernel oil in that order.