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Eutrophication, salinization, hypoxia, and toxic algae, among other environmental damages are costly consequences of agricultural drainage water (ADW), and therefore poses a threat to ecological biodiversity, food security and agriculture sustainability. This work aimed to assess the adsorption efficiency of rice husk (RH) modified by chemical and thermal treatments for sulphate minimization from ADW. RH obtained from a local rice mill was washed in distilled water, oven-dried at 105 ˚C for 24 h, milled and sieved into 0.3–1.18 mm particle sizes. The optimum condition for carbonization was determined by varying the temperature- 200, 300 and 400 ˚C and time- 1, 1.5, and 2 h, respectively. The RH was activated by chemical (H3PO4 and ZnCl2) and thermal treatment. Batch experiments were carried out varying temperature (40-60 °C), adsorption time (15–140 min) and adsorbent dose (1 and 2 g) in an ADW with known sulphate concentration, 30 mg/L. The carbonization yield at 400, 300 and 200 ˚C varies within 18.91- 27.48%, 27.39- 32.82 % and 81.94- 95.75% respectively. It was observed that the percentage of carbon converted into silica increases with burning time; hence, the optimum temperature of 350 ˚C for 2 h was used for carbonization. Also, sulphate adsorption rate increased with contact time and dosage suggesting that the process is controlled by surface and pore diffusion. Based on the temperature study, adsorption was favourable at lower temperatures. H3PO4 and ZnCl2 treated adsorbents have similar removal efficiency; however, ZnCl2 treated adsorbent has a higher efficiency due to its ability to enhance the stability and mesoporosity of carbonaceous material. Modified RH is a potential adsorbent that could be of noble use in ADW quality minimization. However, the huge gap between literature studies and field application needs to be bridged by good extension services and appropriate policy.

Introduction: Cowpea decorticating is a crucial post-harvest process that involves removing the seed coats from the kernels to produce ready-to-use cowpea products such as flour, grits, and protein concentrates and food products such as Akara and Moinmoin in south western Nigeria. Methodology:  In this study, a locally developed cowpea decorticator was tested and evaluated using small oloka (a Nigerian local cowpea breed) cowpea grains. The machine was allowed to run empty for five minutes before the experiment commenced. Three samples of 1kg each were weighed and wetted with same quantity of water for 10, 20, and 30 minutes, respectively. The samples were then fed into the developed decorticator running at a speed of 420 rpm, and the operating speed and time taken were determined using a digital tachometer and stop watch, respectively. Samples of decorticated, undecorticated, and broken cowpea were collected and weighed to evaluate the efficiency of the machine based on the decorticating length and wetting time of cowpea grains. Results: The study revealed that as the decorticating length increased from 44.5 to 178 mm and wetting time increased from 10 to 30 minutes, the decorticating efficiency increased from 55 to 92.1%. The highest average decorticating efficiency of 92.1% was obtained at 178 mm decorticating length and 30 minutes wetting time. Conclusion: These findings showed that the decorticating efficiency of the machine depends on the wetting time and the decorticating length of the machine.

The demand for tomato (Lycopersicon esculentum) as a vegetable and as an industrial raw material is increasing globally. To maximize tomato production and quality, there is need for good water management. This research studied the effect of three irrigation frequencies (F1=7 days; F2= 5 days; and F3= 3 days) and three depths of water applications (D1= 100%ETc; D2 =75%ETc; D3=50%ETc) on some selected food properties of the tomato. The fruits were harvested when observed ripe and the selected food properties were measured. The results from the experiment showed that the moisture content was in the range of 91.44 to 93.53%; crude fibre, 0.64 to 0.69; crude protein, 0.71 to 0.96 %; crude fat, 0.28 to 0.31%; ash content, 0.19 to 0.22%; sodium, 8.62 to 9.02 mg/100g; potassium, 216.33 to 220 mg/100g; calcium, 4.1 to 4.83 mg/100g; phosphorus, 21.12 to 22.73 mg/100g; vitamin C, 20.38 to 22.07mg/100g; and lycopene, 29.73 to 37.08 mg/100g. The statistical analysis of the result showed that the factors examined were not very significant (p<0.05). Thus, the results of the experiment will be useful for engineers who design irrigation water management for the tomato growers for maximizing tomato production through water management. Keywords: Tomato, irrigation regime, irrigation frequency, food qualities, vitamin, water management

In the last few decades, agricultural soils of the world are greatly affected by soil degradation which worsened food security. The ill effects of the unscientific and continuous use of chemical fertilizers coupled with expensive agrochemical input have necessitated the use of manure. Therefore, this work studied the effect of using poultry manure to amend degraded soil on the selected nutritional qualities of African eggplant (Solanum macrocarpon) leaves. Soil samples were collected from an undisturbed degraded area at three depths 0-10, 10-20 and 20-30 cm respectively. The level of degradation was determined and the poultry manure was applied at 0, 10, 15 and 20 t/ha rate respectively. At maturity, the fresh leaves were harvested and the effect of the rate of poultry manure application on moisture content, fat content, crude fibre, crude protein, ash content and carbohydrate content was determined. The highest moisture content (88.88% db), crude protein (4.79%) and ash content (1.79%) were recorded at 20 t/ha poultry manure application while carbohydrate content (4.98%), crude fibre (0.64%) and fat content (1.78%) have its highest at 0 t/ha. The result of this experiment shows great potential for land reclamation using poultry manure. Keywords: land degradation, poultry manure, land reclamation, Africa eggplant, nutritional qualities