International Journal of Plant & Soil Science

Aims: To examine the changes in pH and Eh values of terrace soils during anaerobic incubation when amended with different organic materials, and to study N, P and S release from different manure and bio-slurry in terrace soil under anaerobic condition.

Study Design: The experiment was carried out following Complete randomized design (CRD) with two replications.

Place and Duration of Study: A laboratory incubation study was conducted in Soil Science Laboratory, Bangladesh Agricultural University, Mymensingh in December 2014 for 98 days.

Methodology: The surface (0-15 cm) soil sample was collected from rice growing field of a selected area of Bhaluka, Mymensingh. The incubation study was carried out using four different sources of organic manures with two replications and five treatment combinations. The changes in soil pH, Eh and release pattern of N, P, and S from some organic materials in terrace soil under anaerobic incubation were investigated during December 2014 to April 2015. The soil was amended with all the treatments at 2g 100 g^-1 (air dry basis) soil and incubated for 14 weeks at 25° C. The N, P and S release were determined by the measurement of NH₄-N, phosphate P and SO₄-S on destructive sampling at every two weeks.

Results: The pH values increased at initial stage but gradually decreased over time to neutral and the soil became reduced with the advancement of incubation, it varies (1-3 weeks) depending on the quality of organic matter used. The reduction potential showed a significant variation among the treatments. Overall, when the pH values were averaged over the weeks, the highest pH value was measured in poultry bio-slurry (PB) amended soil followed by poultry manure (PM), cow dung bio-slurry (CDB) and cow dung (CD) amended soils and the lowest was in control. In case of Eh, the most negative (-133.08) Eh value was measured in PM amended soil followed by poultry bio-slurry (PB), CD and CDB amended soils. Control soil had comparatively positive Eh value. At the end of incubation, the highest amount of NH₄-N found in CDB followed by CD, PM, PB and the lowest was in control; the highest amount of phosphate P found in PB followed by PM, control, CDB and CD; the highest amount of SO₄-S found in PB followed by PM, CD, CDB and the lowest was in control.

Conclusion: PB is the best source of organic amendment with respect to release of P and S, whereas CDB showed the best performance in release of N. Nutrient release and availability in reduced environment in terrace soil are a function of soil redox chemistry which is influenced by the quality and quantity of organic matter.

Remote Sensing is an excellent tool in monitoring, mapping and interpreting areas, associated with hydrocarbon micro-seepage. An important technique in remote sensing known as the Soil Adjusted Vegetation Index (SAVI), adopted in many studies is often used to minimize the effect of brightness reflectance in the Normalized Difference Vegetation Index (NDVI), related with soil in areas of spare vegetation cover, and mostly in areas of arid and semi–arid regions. The study aim at analyzing the effect of hydrocarbon micro – seepage on soil and sediments in Ugwueme, Southern Eastern Nigeria, with SAVI image classification method. To achieve this aim, three cloud free Landsat images, of Landsat 7 TM 1996 and ETM+ 2006 and Landsat 8 OLI 2016 were utilized to produce different SAVI image classification maps for the study.  The SAVI image classification analysis for the study showed three classes viz Low class cover, Moderate class cover and high class cover.  The category of high SAVI density classification was observed to increase progressive from 31.95% in 1996 to 34.92% in 2006 and then to 36.77% in 2016. Moderately SAVI density classification reduced from 40.53% in 1996 to 38.77% in 2006 and then to 36.96% in 2016 while Low SAVI density classification decrease progressive from 27.51% in 1996 to 26.31% in 2006 and then increased to 28.26% in 2016. The SAVI model is categorized into three classes viz increase, decrease and unchanged. The un – changed category increased from 12.32km² (15.06%) in 1996 to 17.17 km² (20.96%) in 2006 and then decelerate to 13.50 km² (16.51%) in 2016.  The decrease category changed from 39.89km² (48.78%) in 1996 to 40.45 km² (49.45%) in 2006 and to 51.52 km² (63.0%) in 2016 while the increase category changed from 29.57km² (36.16%) in 1996 to 24.18 km² (29.58%) in 2006 and to 16.75 km² (20.49%) in 2016. Image differencing, cross tabulation and overlay operations were some of the techniques performed in the study, to ascertain the effect of hydrocarbon micro - seepage.  The Markov chain analysis was adopted to model and predict the effect of the hydrocarbon micro - seepage for the study for 2030.  The study expound that the SAVI is an effective technique in remote sensing to identify, map and model the effect of hydrocarbon micro - seepage on soil and sediment particularly in areas characterized with low vegetation cover and bare soil cover.

Aims: To assess the field establishment of two tea cultivars under Cocoa Pod Husk (CPH) and Poultry Manure (PM).

Study Design: Randomized complete block design arranged in Split-plots (cultivars as main plots and organic amendments as sub-plots) with four replications.

Place and Duration of Study: Cocoa Research Institute of Nigeria stations in Ibadan and Owena, Southwest Nigeria between May 2016 and November 2017 (Rainy and dry seasons of 2016; Rainy season of 2017). 

Methodology: Milled CPH and cured PM were applied each at the rates of 150 and 300 kg Nha^-1 to established C143 and C318 tea cultivars on the field; unfertilized tea cultivars served as control. Data on number of leaves, number of branches, leaf area, plant height and stem diameter were collected on monthly basis; while dry matter was assessed at 15 months after transplanting. The data were analyzed with ANOVA and correlation at α_.05.

Results: The C143 performed better than C318 and 150 kg Nha^-1 of CPH and PM enhanced the vegetative growth and dry matter of tea better than 300 kg Nha^-1 in Ibadan and Owena. Cultivar 143 was significantly (P=0.05) better than cultivar 318 in number of leaves, number of branches and stem diameter in Ibadan; and in number of leaves and leaf area in Owena. CPH at 150 kg Nha^-1 increased number of leaves, number of branches, leaf area, plant height and total dry matter by 135.11, 88.19, 346.12, 65.33 and 428.11% at Ibadan; and by 349.09, 245.41, 376.89, 80.89 and 231.49% at Owena, compared to control. On the interaction, tea cultivar 143 that received 150 kg Nha^-1 CPH produced significantly (P=0.05) higher number of leaves, leaf area and total dry matter at Ibadan and Owena. Leaf area was positively correlated with number of leaves (r=0.87) in Ibadan and stem diameter (r=0.80) in Owena.

Conclusion: CPH at 150 kg Nha^-1 enhanced the growth and dry matter content of C143 tea established on the field in Ibadan and Owena, and is therefore recommended for tea cultivation in Southwest of Nigeria.

Application of manure for soil amendment plays important roles in reclaiming and improving soil properties of degraded soils. This study assessed the effects of composted and non-composted manures on a degraded soil under continuous maize production. The treatments applied consisted of composted manures in form of cassava based compost (CBM) and verticompost (VC) at the rate of 0, 30, 60 and 120 tons/ha, non-composted manure (NC) applied as poultry manure (PM), and an un-amended control plot. These treatments were laid out in a randomized complete block design replicated three times. Soil physical and chemical properties were determined for two consecutive seasons, with maize (SUWAN 1-SYR) planted as test crop. The CBM, VC and PM treatments increased the soil organic carbon content by 18.2, 24.1, and 22.3 % respectively. Corresponding increases observed in cation exchange capacity (CEC) were 13.6, 15.7, and 15.2 %. The comparison of the soil chemical properties measured indicated positive effects from the amendments on the soil properties in the order: CBM < PM < VC.  The maize grain yield of cassava based fertilized plot consistently and significantly was higher than the other treatments in both cropping seasons. However, both the composted and non-composted manures favored improved maize growth and resulted in higher grain yields (4.62 – 6.03 t ha^-1) than the un-amended control treatment (3.69 t ha^-1). The study therefore showed that the incorporation of manures, whether composted or non-composted, is beneficial to soils, improving one or more essential soil attributes thus reducing soil degradation.

A field experiment was conducted to determine the effect of combined application of fortified poultry manure with ash and NPK fertilizer on the performance of sakanal onions (Allium cepa L.) variety during 2018/2019 dry season in Chimola (Gwadabawa LGA) and Wurno (Wurno LGA), Sokoto State. The treatments consisted of three (3) levels combination of fortified poultry manure with ash (1:3 ratio) at 5, 10 and 15t ha^-1 and three (3) levels of NPK at 30, 45 and 60kg ha^-1 which were combined and laid-out in a randomized complete block design (RCBD) replicated three (3) times. Sakanal onion variety was used as a test crop. The data generated were subjected to analysis of variance (ANOVA) procedure for RCBD using SPSS version 23.0. The results revealed that fortified poultry manure with ash and NPK fertilizer significantly (P<0.05) affected Growth and yield parameters such as plant height (71 - 62 cm), number of leaves (8), fresh bulb yield (70t ha^-1), crop growth rate (1.52g cm^-1) in Chimola and Wurno. Individual bulb weight (300g), bulb diameter (7.8cm) were significantly (P<0.05) affected in Wurno location. Cured buld yield (55t ha^-1) responds significantly (P<0.05) to the application of fortified poultry manure with ash and NPK fertilizer in Chimola location. The result of the study revealed that application of fortified poultry manure with ash and NPK fertilizer (P15NPK3) significantly improved the performance and shelf-life of sakanal onion variety and physical and chemical properties of the soils in the study area.

The production of pepper is low due to decrease in fertility of soil and inadequate storage structures. The study was aimed at evaluating the growth, yield and storage qualities of selected pepper varieties as influenced by poultry manure and storage structures in Ibadan, Nigeria. A field experiment was carried out at Department of Agronomy, University of Ibadan between November, 2017 and April, 2018 growing season. Two varieties of pepper (Capsicum annum and Capsicum frutescens) were used, with four treatments consisting of different rates of poultry manure. Controls of 0 g of poultry manure (T1), 12.5 g (T2), 25 g (T3) and 37.5 g (T4) were laid out in a complete randomised design and replicated four times. Storage experiment was carried out in the Department and at Nigeria Stored Products Research Institute (NSPRI), Ibadan in June, 2018. The storage experiment comprised of four treatments with ambient condition (open shelf), wet basket, Evaporative Coolant Structure (ECS/Pot-in-pot), and plastic crates used as storage structures, laid out in a completely randomised design and replicated three times. The physical parameters obtained in days in storage (DIS) included weight loss (%), firmness, freshness, among others. Data observed were subjected to analysis of variance (ANOVA) and means separated using least significant difference (LSD) at p>0.05. The result obtained showed that pepper growth was enhanced using Capsicum frutescens under 25 g poultry manure application rate which resulted to superior pepper yield. The combination of pot-in-pot with sawdust as storage structures enhanced the storage qualities of pepper fruits within the two weeks of storage. Although, the different manure treatments had no significant effect on the postharvest quality of pepper, the ECS can be effectively used in the storage of pepper fruits in order to improve postharvest quality, extend shelf life and enhance affordability of the commodity at all seasons.

The study aimed to study the efficacious response of maize growth and soil changes to phosphorous and zinc application on chromic luvisols in North-eastern part of Nigeria conducted at Teaching and Research Farm of School of Agriculture and Agricultural Technology, Modibbo Adama University, Yola during 2018 and 2019 cropping seasons. Randomized Complete Block Design (RCBD) was used in the experiment to test the various levels of P and Zn applications on TZL composite white improved variety of maize. Four levels of phosphorus (0, 10, 20 and 30 kg Pha-1) and three levels of zinc (0, 5 and 10 Zn ha-1) were applied on experimental plots of 4.5m x 5m replicated three times. Data obtained on the growth parameters and soil properties were measured and analyzed using ANOVA statistical package. Result indicate that the soil was predominantly sandy loam, organic matter (mean =0.92 gkg-1), total N (mean = 0.35 gkg-1) Available phosphorous (mean = 8.6 mgkg-1) Zinc (mean = 7.25 mgkg-1) and exchangeable cations (means= Ca²⁺ =0.26 cmolkg-1, Mg²⁺ =0.27 cmolkg-1, K+ =1.83, Na+ =0.85 cmolkg-1) and CEC = 5.32 respectively. The effects of P and Zn did not show any significant difference on plants height in both years of experimentation except at harvest where main effect of P showed slightly taller plants at  30 kg Pha^-1 level in 2018 (202.11 cm) and 2019 (206.11 cm). Generally the mean values of plant heights at various P levels are higher than that at the Zn levels. Similarly, there were no significant differences in the leaf area, however, highest mean values of 236.1 cm² and 227.6 cm² was observed at 30 kg Pha^-1 and 10 kg Znha^-1 in both 2018 and 2019 cropping years. while Leaf Area Index shows highest values of 2.98 cm² and 2.54 cm² observed at 30 kg Pha^-1 and 10 kg Znha^-1 and interaction effects was significant P = (0.05) in both years respectively. Available P in soil after the harvest of 2018 the available P was significantly affected. Highest mean values of P content were 13.14 mgkg^-1 and 14.97 mgkg^-1 in 2018 and 2019 with 30kg Pha^-1. Also, there was significant difference in the main effect of the Zinc treatments on available Zn in the soil in 2019 where the highest mean value of 4.03 mgkg^-1 was recorded at 0 kg Zn ha^-1. Therefore, application of 30 kg P ha-¹ and 10 kg Zn ha-¹ as evidenced to maintain the soil nutrients and thus should be employed for sustainable maize production in the area.