ir.bowen.edu.ng:8181/jspui/handle/123456789/335 These are articles published in journals by academics staff 2026-04-22T00:07:18Z ir.bowen.edu.ng:8181/jspui/handle/123456789/3073 Title: Effects of cocoa pod ash and urea on soil chemical properties and the performance of kale (Brassica oleracea L.) in derived savanna zone of Nigeria Authors: Adekiya, A. O.; Aboyeji, C. M.; Dunsin, O.; Agbede, T. M.; Bazuaye, H. Abstract: Potted experiments were carried out at the Teaching and Research Farm, Landmark University, Nigeria between January and March (1st crop) and April and June (2nd crop), 2015. The aim was to investigate the effects of sole and integrated application of cocoa pod ash (CP) and urea fertilizer (UF) on soil chemical composition and performance of kale (Brassica oleracea L.). There were 12 treatments comprising 3 levels of UF (0, 100, 200 kg/ha) and 4 levels of CP (0, 5, 10 and 15 t/ha). The treatments were arranged in a Completely Randomised Design, replicated three times. For the 1st and 2nd crops of kale, CP alone and integration with UF, increased soil chemical properties compared with the control where neither CPA nor UF was applied. Treatments with 5 t/ha cocoa pod ash + 100 kg/ha urea fertilizer (CP5U100) and 5 t/ha cocoa pod ash + 200 kg/ha urea fertilizer (CP5U200) consistently had the higher values of N, K Ca and Mg in the soil after both the 1st and 2nd kale crops and the mean values of both crops. Treatments with CP5U100 and CP5U200 had significantly higher and similar values of plant height, number of leaves and other yield parameters (root weight, stem weight, leaf weight, stem girth and stem length) of kale compared with other treatments. Compared with the control, CP5U100 and CP5U200 increased the leaf weight of kale by 243 and 268%, respectively. Therefore, integration of cocoa pod ash at 5 t/ha with 100 kg/ha urea fertilizer may be recommended in the production of kale in the derived savanna zone of Nigeria to cut down on the use of urea and its rising cost. More research is, however, needed involving field experimentation and additional soil types to make a firm recommendation. 2018-01-01T00:00:00Z ir.bowen.edu.ng:8181/jspui/handle/123456789/3072 Title: Effects of split application of urea fertilizer on soil chemical properties, maize performance and profitability in southwest Nigeria Authors: Ogunboye, Oluwaseyi I.; Adekiya, Aruna O.; Ewulo, Babatunde S.; Olayanju, Adeniyi Abstract: Since N fertilizer applied to maize (Zea mays L.) is prone to loss by leaching, it is important to derive an application time during the phenology of maize when the fertilizer is most efficiently and effectively used by the crop with minimal losses. Hence, experiments were carried out in 2014 at two locations in Osogbo southwest Nigeria to determine the effects of split application of N fertilizer on soil chemical properties, maize performance, and profitability. The treatments were: (i) control, (ii) 120 kg N ha-1 Applied at Planting (AP), (iii) two split applications (SA) of 120 kg N ha-1 {90 kg N ha-1 applied AP + 30kg N ha-1 at thirty Days After Planting (DAP) [90 + 30]}, and (iv) three SA of 120 kg N ha-1 {60 kg N ha-1 applied AP + 30 kg N ha-1 thirty DAP + 30 kg N ha-1 at tasselling[60+30+30]}. The four treatments were arranged in a Randomized Complete Block Design with three replicates. Results indicate that at both sites, SA three times (60+30+30) has the most improved soil chemical properties, growth and yield of maize relative to other methods. The yield parameters increased in the order: control < 120 kg N ha-1 applied once < 90+30 < 60+30+30. Using the mean of both sites, 60+30+30 increased yield of maize by 15.3%, 37.1% and 138.2%, respectively compared with 90+30, 120 kg N ha-1 applied once and the control. Optimum returns were recorded by 60+30+30 with net return of ₦ 227,600 and a benefit-cost ratio of 3.67:1 while the application of 120 kg N ha-1 applied once has a return of ₦ 157,200 with a benefit ratio of 2.9. These results show that farmers would benefit by making more profit by adopting the method of SA of N fertilizer three times (60+30+30). Therefore, for improved soil chemical properties, growth, yield and profitability of maize, N fertilizer application should be structured in accordance with this pattern of uptake to avoid losses by leaching and therefore ensure that N level in the soil is high at the critical stage of N demand. 2020-01-01T00:00:00Z ir.bowen.edu.ng:8181/jspui/handle/123456789/3071 Title: Effects of organic fertilizers on yam productivity and some soil properties of a nutrient-depleted tropical Alfisol Authors: Agbede, T. M.; Adekiya, A. O.; Ogeh, J. S. Abstract: Field experiments were conducted at Owo, southwest Nigeria to select organic fertilizer treatments most suitable for sustaining high soil fertility and yam productivity on a nutrient-depleted tropical Alfisol. Eight organic fertilizer treatments were applied at 20 t ha-1 with a reference treatment inorganic fertilizer (NPK 15–15–15) at 400 kg ha-1 and natural soil fertility (control), laid out in a randomized complete block design with three replications. Results showed that organic fertilizers significantly increased (p = 0.05) tuber weight and growth of yam, soil and leaf N, P, K, Ca and Mg, soil pH and organic C concentrations compared with the NSF (control). The oil palm bunch ash + poultry manure treatment increased tuber weight, vine length, number of leaves and leaf area of yam by 66, 25, 21 and 52%, respectively, compared with inorganic fertilizer (NPK) and 37, 22, 19 and 44%, respectively, compared with poultry manure alone. Sole or mixed forms of organic fertilizers showed significant improvement in soil physical conditions compared with IF (NPK) and NSF (control). Synergistic use of oil palm bunch ash + poultry manure at 10 t ha-1 each was most effective for sustainable management of soils and for improving agronomic productivity of yam. 2013-01-01T00:00:00Z ir.bowen.edu.ng:8181/jspui/handle/123456789/3070 Title: Effects of organic and inorganic fertilizers on sweet potato production in Iwo, Nigeria Authors: Esan, V. I.; Omilani, O. O.; Okedigba, I. Abstract: Sweet potato (Ipomea batatas) is one of the most important horticultural crops for human consumption and livestock feed. All parts of the plant are found useful to human consumption, animal feed, and industrial uses. Fertilizer applications have been shown to improve vegetative and storage parameters could be enhanced, but inorganic fertilizers are not always readily available, or are too expensive for prevalently subsistent farmers in Nigeria. This study aimed to compare the performance characteristics of four potato varieties using two fertilizers from inorganic and organic sources using morphological characteristics of the plants. The experiment was carried out in the field and laid out as randomized complete block design with three replications. Two treatments that is, inorganic and organic fertilizers with three levels for each treatment were used. The yield and other morphological characteristics were measured. The results showed that Iwo 1 (variety 3) produced the highest number of tubers (16.67 and 16.69; 16.67 and 16.33) with both inorganic and organic fertilizers and levels, respectively. Iwo 1 (variety 3) also produced the biggest tuber weight (4.57 and 4.60 kg; 3.97 and 3.88 kg) with both inorganic and organic fertilizers and levels, respectively. The results showed significantly (P≤0.05) similar levels of performance of organic fertilizers when juxtaposed with inorganic fertilizer applications, suggesting that in the absence of inorganic fertilizers either due to cost and or availability, organic fertilizers which are relatively more available to the farmer could be used to obtain similar yield levels. Given the bulky nature of the fertilizers as suggested by the quantity used in this experiment, further research will need to be done to determine the best rate for organic fertilizer application. 2021-01-01T00:00:00Z