Impacts of poultry manure and biochar amendments on the nutrients in sweet potato leaves and the minerals in the storage roots.

Poultry manure (PM) has demonstrated its potential to enhance crop nutritional quality. Nevertheless, there remains a dearth of knowledge regarding its synergistic effects when combined with wood biochar (B) on the nutrient concentrations in sweet potato leaves (Ipomoea batatas L.) and the mineral content stored in sweet potato storage roots. Hence, a two-year field trial was undertaken during the 2019 and 2020 cropping seasons in southwestern Nigeria, spanning two locations (Owo-site A and Obasooto-site B), to jointly apply poultry manure and wood biochar as soil amendments aimed at enhancing the nutritional quality of sweet potato crop. Each year, the experiment involved different combinations of poultry manure at rates of 0, 5.0, and 10.0 t ha-1 and biochar at rates of 0, 10.0, 20.0, and 30.0 t ha-1, organized in a 3 × 4 factorial layout. The results of the present study demonstrated that the individual application of poultry manure (PM), biochar (B), or their combination had a significant positive impact on the nutrient composition of sweet potato leaves and minerals stored in the sweet potato storage roots, with notable synergistic effects between poultry manure and biochar (PM × B) in enhancing these parameters. This highlights the potential of biochar to enhance the efficiency of poultry manure utilization and improve nutrient utilization from poultry manure. The highest application rate of poultry manure at 10.0 t ha-1 and biochar at 30.0 t ha-1 (PM10 + B30), resulted in the highest leaf nutrient concentrations and mineral composition compared to other treatments at both sites. Averaged over two years, the highest application rate of poultry manure at 10.0 t ha-1 and biochar at 30.0 t ha-1 (PM10 + B30) significantly increased sweet potato leaf nutrient concentrations: nitrogen by 88.2%, phosphorus by 416.7%, potassium by 123.8%, calcium by 927.3%, and magnesium by 333.3%, compared to those in the control (PM0 + B0). The same treatment increased the concentration of sweet potato root storage minerals: phosphorus by 152.5%, potassium by 77.4%, calcium by 205.5%, magnesium by 294.6%, iron by 268.4%, zinc by 228.6%, and sodium by 433.3%, compared to the control. The highest application rate of poultry manure at 10.0 t ha-1 and biochar at 30.0 t ha-1 yielded the highest economic profitability in terms of gross margin (44,034 US$ ha-1), net return (30,038 US$ ha-1) and return rate or value-to-cost ratio (VCR) (263). The results suggested that the application of poultry manure at 10 t ha-1 and biochar at 30 t ha-1 is economically profitable in the study areas and under similar agroecological zones and soil conditions.

Mineralogical compositions of soils under three geological formations in some parts of Ogun state, Nigeria and their agricultural potentials.

Investigating the mineralogical compositions of soils under different geological formations becomes imperative for maximizing agricultural productivity and ensuring the long-term viability of agricultural practices. Therefore, studies were carried out on mineral compositions and diversities of soils developed over the Basement complex rock, Coastal plain sands and Ewekoro formations in Ogun state Nigeria. A total of nine profile pits (three per location) of 2 m × 1 m × 2 m size were dug in all the three locations. Soil samples were collected from the pedogenic horizons of each profile pits in replicates into a well labeled polyethylene bag. Using X-ray diffractometry (XRD) and scanning electron microscopy (SEM) the mineral contents and their relative abundance, elemental compositions and morphologies of the fine sand, coarse silt and clay fractions of the soils at different topographic positions were identified, described and compared. Results obtained from XRD and SEM analyses exhibited similarities. The most abundant elements in the basement complex and Ewekoro pedon were oxygen, carbon and silicon whereas in the coastal plain sand pedon, oxygen, carbon and aluminum were the most abundant element. The presence of mixed-layer illite, mica, kaolinite, quartz, hematite, anatase, goethite, and chlorite at varying degrees was observed in the pedons developed on these geological formations, although kaolinite and quartz dominated the soil matrix. The mineralogical complexity of the pedons followed the order of basement complex > coastal plain sand > Ewekoro formation. Profiles developed on the Ewekoro formation exhibited the highest degree of weathering, as evidenced by their chemical properties and mineralogical compositions. The petrographic evaluation of the three geological formations revealed that all pedons were rich in quartz and exhibited varying degrees of mineral complexity and maturation. The overlapping and distinct characteristics among the geologies indicated different stages of weathering. By using the mineral maturity index, profiles developed over the basement complex rock and the coastal plain sand could be regarded as sub-matured and this could have contributed significantly to the native fertility of these soils and profiles from the Ewekoro formation were the most weathered. The use of Ewekoro formation for agriculture would necessitate significant investments in agro-inputs and sound principles of soil management through integrated soil fertility management.

Sole and Combined Application of Biodigestate, N, P, and K Fertilizers: Impacts on Soil Chemical Properties and Maize Performance.

The fertilizing effects of biodigestate produced from biogas plants on crop and soil productivity are very scarce. Hence, a field study was conducted in 2022 at the Teaching and Research Farm of Bowen University, Iwo, Osun State, Nigeria. The study evaluated the effects of biodigestate fertilizer, applied alone or in combination with urea, single superphosphate, or muriate of potash fertilizers at low (N1, K1, and P1) and high (N2, P2, and K2) rates on soil chemical properties, growth, and yield of maize (Zea mays (L.)). The treatments were biodigestate alone (D), D + N fertilizer (urea) at 60 kg·ha-1 (DN1), D + N at 120 kg·ha-1 (DN2), D + P fertilizer (single superphosphate) at 30 kg·ha-1 (DP1), D + P at 60 kg·ha-1 (DP2), D + K fertilizer (muriate of potash) at 30 kg·ha-1 (DK1), D + K 60 kg·ha-1 (DK2), D + N1 + P1 + K1 (DN1P1K1), D + N2 + P2 + K2 (DN2P2K2) (10), and control. The 10 treatments were arranged in a randomized complete block design and replicated three times. Results showed that both low and high rates of fertilizer application improved soil chemical properties, growth parameters, and yield of maize compared with the control. High fertilizer rates (N2, P2, and K2) significantly enhanced soil chemical properties and growth parameters, but lower rates (N1, P1, and K1) resulted in higher maize yield. DN1 fertilizer significantly increased maize yield compared with DN2, DP1, DP2, DK1, and DK2. Overall, the treatment of DN1P1K1 demonstrated the highest grain yield, likely due to optimal nutrient supply from N, P, and K fertilizers, along with an improved soil environment facilitated by the biodigestate. The study recommends a balanced and sustainable fertilizer application strategy of 60 kg·N·ha-1, 30 kg·P2O5·ha-1, and 30 kg·K·ha-1 with 2500 L·ha-1 of biodigestate to enhance maize production while minimizing cost and environmental impact. However, for those aiming for maize fodder production, a higher fertilizer rate of 120 kg·N·ha-1, 60 kg·P2O5·ha-1, and 60 kg·K·ha-1 with 2500 L·ha-1 of biodigestate is advised.

Combined lime and biochar application enhances cowpea growth and yield in tropical Alfisol.

It is essential to increase the pH of tropical soils in order to reduce acidity and promote soil and crop productivity. Therefore, experiments were carried out in 2020 and 2021 to assess the impacts of biochar and lime on the chemical properties, growth, nodulation, and yield of cowpea (Vigna unguiculata). The study involved various levels of lime (CaCO3) and wood biochar (ranging from 0 to 10 t ha-1), organized in a factorial combination. The treatments were arranged in a randomized complete block design and replicated three times. The application of lime and biochar, either separately or in combination, led to improvements in soil chemical properties such as pH, nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), sodium (Na), magnesium (Mg), and cation exchange capacity (CEC), as well as enhancements in the growth, nodulation, and yield of cowpea when compared to the control. Lime and biochar alone and combined reduced exchangeable acidity (Al + H) relative to the control. Cowpea yield increased with lime rate up to a point, but then decreases. The highest cowpea yield is achieved at a lime rate of 2.5 t ha-1, whereas cowpea yield increased as the Biochar rate increased from 0 up to 10 t ha-1. There was a significant correlation between pH and cowpea pod weight in both years (2020 and 2021). The R values were - 0.615 and - 0.444 for years 2020 and year 2021 respectively at P < 0.05. At higher lime levels combined with biochar, there were considerable reductions in cowpea yield, and this decrease can be attributed to unfavorable soil pH conditions. Relative to 2.5 t ha-1 lime + 5 t ha-1 biochar, 10 t ha-1 lime + 10 t ha-1 biochar, reduced cowpea grain yield by 853% in 2020 and 845% in 2021. Since there were no significant differences between the effects of 2.5 t ha-1 lime + 5 t ha-1 biochar, 2.5 t ha-1 lime + 7.5 t ha-1 biochar, and 2.5 t ha-1 lime + 10 t ha-1 biochar applications on cowpea yield, therefore to prevent waste of Biochar, 2.5 t ha-1 lime + 5 t ha-1 biochar is recommended for production of cowpea.

Potentials of plantain peel and Tithonia diversifolia leaves as soil amendments in enhancing performance and nutritional contents of tomato (Solanum lycopersicum).

Screen house experiment was conducted in 2020 at the Landmark University Teaching and Research Farm Omu-aran, Kwara State. The experiment was carried out to evaluate the potential of dried unripe plantain peel and Tithonia diversifolia as soil amendments and its effect on growth, yield and fruit quality of tomato. Four rates each of dried plantain peel (0, 5, 10 and 15 t/ha) and Tithonia diversifolia (0, 10, 20 and 30 t/ha) were applied sole and combined. The experimental layout was a completely randomized design (CRD) with three replicates. Parameters were collected on the plant height, number of leaves, number of branches, stem girth, yield and fruit quality. Data collected were subjected to Analysis of variance (ANOVA) using the GENSTAT Discovery Software, Edition 4. Comparison of the treatment means were carried out using Duncan Multiple range test (DMRT) at 0.05 level of probability. Results showed that dried plantain peel and Tithonia diversifolia improved, number and weight of fruits as well as the fruit quality of tomato and were comparable to the application of NPK fertilizer. Treatment P5T30 (T8) increased number of leaves and number of branches while P15T20 (T15) and P10T30 (T12) increased plant height and stem girth respectively. Treatment P5T30 (T8) and P10T20 (T11) also significantly improved the fruit quality (minerals, lycopene and Vit. A) of tomato fruits. It can therefore be concluded that application of dried plantain peel and Tithonia diversifolia at P5T30 (T8) and P10T20 (T11) increased the vegetative, yield and quality parameters of tomato in the screen house of the study area.

Effects of wood biochar and potassium fertilizer on soil properties, growth and yield of sweet potato (Ipomea batata).

Studies on integrating biochar with potassium (K) fertilizer is not common. Hence, experiments were conducted in 2020 and 2021 to evaluate the sole and combined applications of biochar and K fertilizer on soil properties and performance of sweet potato. It was hypothesized that the effects of combined applications of biochar and K fertilizer on the growth, and yield of sweet potato will be more than their individual applications. The study each year consisted of a 3 × 3 factorial experiment with three levels (0, 10, and 20 t ha-1) of wood biochar and three levels (0, 70, and 120 kg ha-1) of K fertilizer (potassium chloride). The 9 treatment combinations have three replications and follow a randomized complete block design. Results revealed that biochar alone or in combination with K fertilizer improved soil physical and chemical properties, growth, and yield of sweet potato relative to the control and K fertilizer alone. The interaction of biochar and K (biochar × K fertilizer) fertilizer was significant for growth and yield parameters. The addition of K fertilizer to biochar improved the performance of sweet potato compared with sole applications of K fertilizer or biochar. 20 t ha-1 biochar +70 kg ha-1 K fertilizer and 20 t ha-1 biochar +120 kg ha-1 K fertilizer increased growth and yield relative to 10 t ha-1 biochar +70 kg ha-1 K fertilizer and 10 t ha-1 biochar +120 ha-1 kg K fertilizer. Since 20 t ha-1 biochar +120 kg ha-1 K fertilizer and 20 t ha-1 biochar +70 kg ha-1 K fertilizer were statistically similar, for this experiment, 20 t ha-1 biochar +70 kg ha-1 K fertilizer would be recommended for sweet potato production. Therefore, the addition of 70 kg K fertilizer with biochar has reduced the cost of increasing the rate to 120 kg ha-1 which would have been economical in view of the high price and lack of K fertilizer in Nigeria and other sub-Saharan African countries.

Organic and in-organic fertilizers effects on the performance of tomato (Solanum lycopersicum) and cucumber (Cucumis sativus) grown on soilless medium.

The effects of organic fertilizers, based on Tithonia diversifolia, and in-organic fertilizers, based on hydroponics fertilizer, were evaluated on the performance, leaves, and fruit mineral concentrations of tomato (Solanum lycopersicum) and cucumber (Cucumis sativus) plants grown under soilless medium in a screen house. The treatments comprised six levels of liquid organic fertilizer (5, 15, 25, 35, 45, 55 mL), in-organic fertilizer, and a control. Both organic and in-organic fertilizers increased the growth, yield, leaf nutrient concentration, and the mineral contents of tomato and cucumber fruits in comparison with the control. In-organic fertilizer enhanced the performance and mineral concentrations of tomato and cucumber fruits in comparison with organic fertilizer. However, leaf analyses showed that all the essential elements for both tomato and cucumber crops were within the adequate ranges in the organic fertilizer treatments suggesting that this organic fertilizer can be used as an alternative to the expensive and scarce in-organic fertilizer. For organic fertilizer, the highest yield and mineral contents in fruits were attained at doses of 35 mL and 25 mL for tomato and cucumber plants, respectively. At these doses, the fruit weights of tomato and cucumber were increased by 137 and 198%, respectively, in comparison with the control. For a good yield of tomato and cucumber crop with a high fruit mineral content under the soilless medium of coco peat and rice husk, 35 mL and 25 mL of our tested organic fertilizer are recommended.

Soil productivity improvement under different fallow types on Alfisol of a derived savanna ecology of Nigeria.

Fallowing is considered an important management strategy for the restoration of soil productivity. Therefore, a three-year fallow of pigeon pea (Cajanus cajan), mexican sunflower (Tithonia diversifolia) and elephant grass (Pennisetum purpureum) was established at Landmark University, Nigeria between 2016 - 2019. Leaf nutrient concentrations of maize (Zea mays) planted with soils taken from each fallowed plots after three years were also determined. The experimental design was a randomized complete block design with three replications. Soil samples were collected from each fallow plots for physical and chemical analysis (bulk density, porosity, moisture content, particle size, dispersion ratio, soil erosion loss, soil organic matter (SOM), total N, available P, exchangeables K, Ca, Mg, CEC and pH.) before and at the end of the experiment. Means of data collected were separated using Tukey's HSD test at p = 0.05. Tithonia fallow improved soil properties and leaf nutrient concentration of maize compared with Pennisetum and Cajanus fallows. The order was Tithonia > Pennisetum > Cajanus. This was adduced to the regular return of plant residues to the soil in Tithonia fallow which resulted in high SOM (Tithonia increased SOM by about 23%, 7.5%, and 20%, respectively, compared with the initial soil, Pennisetum and Cajanus fallows) and increases soil N, P, K, Ca, Mg, CEC and pH and also stabilized soil structure by increasing porosity, moisture content and reducing bulk density, dispersion ratio, and soil loss. Therefore, plant species of high nutrient contents and high return of biomass to the soil are necessary for quick restoration of soil productivity in a derived savanna ecology.

Performance and quality attributes of okra (Abelmoschus esculentus (L.) Moench) fruits grown under soil applied Zn-fertilizer, green biomass and poultry manure.

Field experiments were carried out in 2018 and 2019 cropping seasons at Landmark University Teaching and Research farm, Omu-Aran Kwara state, Nigeria, to determine the effect of soil applied Zn-fertilizer, Tithonia diversifolia (Ti), Chromolaena odorata (Ch) and poultry manure (PM) on the performance, yield, minerals and vitamins composition of okra fruits. Treatments were combined and tested as follows:-Control (T1), Control + 10 kg ha-1 Zn (T2), 5 t ha-1 Ti + 5 t ha-1 PM (T3), 5 t ha-1 Ch + 5 t ha-1 PM (T4), 5 t ha-1 Ch + 5 t ha-1 Ti (T5), 10 t ha-1 Ti + 0 kg ha-1 Zn (T6), 10 t ha-1 Ti + 10 kg ha-1 Zn (T7), 10 t ha-1 Ch + 0 kg ha-1 Zn (T8), 10 t ha-1 Ch + 10 kg ha-1 Zn (T9), 10 t ha-1 PM + 0 kg ha-1 Zn (T10), and 10 t ha-1 PM + 10 kg ha-1 Zn (T11). The experiment was laid out in a randomized complete block design with four repetitions. Vegetative, yield and quality parameters of okra were taken. Data were subjected to analysis of variance and means were compared using Duncan Multiple Range Test (DMRT) at p ≤ 0.05. Variations were observed on the vegetative parameters, yield, minerals and vitamin composition of okra among the applied amendments. The combined application of green biomass, poultry manure, and Zn-fertilizer improved all the variables tested as compared to when they were applied singly. Application of Zn-fertilizer to some selected plots significantly increased yield, Zn, Mg and vitamins concentration of okra. Application of 5 t ha-1 Ti + 5 t ha-1 PM + 10 kg ha-1 Zn (T3) and 5 t ha-1 Ch + 5 t ha-1 PM + 10 kg ha-1 Zn (T4) significantly improved all the parameters tested but the use of 5 t ha-1 Ti + 5 t ha-1 PM + 10 kg ha-1 Zn (T3) resulted in optimum yield and at the same time increase minerals and vitamin concentration of okra. The results of this study therefore showed that Tithonia diversifolia (Ti) as green biomass contained and released more and quality nutrients than Chromolaena odorata (Ch) when combined with equal rate of Zn fertilizer and poultry manure.

Effects of cow dung and wood biochars and green manure on soil fertility and tiger nut (Cyperus esculentus L.) performance on a savanna Alfisol.

Two field experiments were conducted concurrently in 2019. The study investigated the effects of single and combined application of wood biochar (WB) and cow dung biochar (CDB) with green manure (GM) on soil properties, performance, and tuber qualities of tiger nut. The treatments consisted of: CDB at 10 t ha-1, WB at 10 t ha-1, GM-Tithonia diversifolia at 10 t ha-1, CDB + GM, WB + GM, control. The six treatments were arranged in RCBD with three replications. CDB, WB, and GM either sole or combined increased moisture content, SOC, nutrient contents, culturable microorganisms, performance, moisture, ash, fiber, and protein contents of the tiger nut compared with the control. CDB has a higher N, C: N ratio, P, K, Ca, Mg, CEC, and pH relative to. CDB alone and CDB + GM increased growth and yield compared with WB alone and WB + GM. CDB + GM has the highest value of growth and yield of tiger nut. GM alone improved growth and yield of tiger nut compared with the two sole biochar treatments. CDB + GM and WB + GM increased growth and yield of tiger nut compared with their sole forms. This was adduced to biochar allowing the retention of nutrients from rapidly decomposing Tithonia within the rooting zone, thereby promoting better effectiveness of nutrient uptake and increase in yield. Therefore, for good soil fertility and tiger nut yield, it is important that the addition of a fast releasing nutrient source to biochar be sought.

Different organic manure sources and NPK fertilizer on soil chemical properties, growth, yield and quality of okra.

Use of organic manures to meet the nutrient requirement of crop would be an inevitable practice in the years to come for sustainable agriculture since organic manures generally improve the soil physical, chemical and biological properties. Hence, field experiments were carried out in 2017 and 2018 to compare the impact of different organic manures and NPK fertilizer on soil properties, growth, yield, proximate and mineral contents of okra (Abelmoschus esculentus L.). The treatments each year 2017 and 2018 consisted of: rabbit manure, cow dung, poultry manure, green manure [Mexican sunflower (Tithonia diversifolia Asteraceae)], pig manure, NPK 15-15-15 fertilizer applied at 120 kg N ha-1 and a control (no manure/inorganic fertilizer). The seven treatments were laid out in a randomized complete block design with three replication. Organic manures and NPK fertilizer increased the soil organic matter (OM), N, P, K, Ca and Mg (NPK fertilizer did not increase OM, Ca and Mg significantly), growth, yield, minerals, protein, ash, carbohydrate and mucilage contents of okra fruit as compared with control. Organic manures improved okra yield compared with NPK fertilizer. Okra growth and yield parameters were significantly higher in 2018 compared with 2017. Control, rabbit manure, cow dung, poultry manure, green manure, pig manure and NPK fertilizer in 2018 increased the pod yield of okra by 9.7%, 35.3%, 57.9%, 36.2%, 39.2%, 45.5% and 3.2%, respectively compare with the same treatment in 2017. Amongst various organic manures, poultry manure produced significantly higher plant growth, yield, mineral and proximate composition of okra because of its high soil chemical properties which could be related to its lowest C: N ratio, lignin and lignin: N ratio. Results also showed that okra grown during high intensity rainfall has higher yield but with reduced quality except its mucilage content. Therefore, planting of okra with poultry manure under moderate rainfall will enhance the health benefit from the fruit, however, those that desire its mucilage content planting during high rainfall is recommended.

Effects of Different Rates of Poultry Manure and Split Applications of Urea Fertilizer on Soil Chemical Properties, Growth, and Yield of Maize.

During integrated nutrient management involving poultry manure (PM) and urea fertilizer (UF) for maize (Zea mays L.), it is necessary to investigate the best time to apply UF that will optimize soil chemical properties, growth, and yield of maize. Hence, studies were carried out to investigate the effect of different rates of PM and single and split applications (SA) of UF on soil chemical properties, growth, and yield of maize. The treatment involved three levels of PM (0.0, 4.0, and 8.0 t·ha-1) and four sets of periods of UF: (i) 0 kg N ha-1 (control), (ii) 120 kg N ha-1 applied at planting (AP), (iii) two SA of 120 kg N ha-1 (90 kg N ha-1 applied AP + 30 kg N ha-1 at thirty days after planting (DAP)), 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 tasseling). The 12 treatments were arranged in a randomized complete block design and replicated three times. PM and UF alone and integrating UF with PM improved soil chemical properties, growth, and yield of maize compared with the control. SA of UF three times (60 + 30 + 30) had the most improved soil chemical properties, growth, and yield of maize. Results also showed that maize yielded higher under UF integrated with PM compared with their sole forms. Application of 60 + 30+30 with 8 t ha-1PM (60 + 30+30 + 8 t ha-1PM) or with 4 t ha-1PM treatments showed the highest growth and yield of maize, but due to the bulkiness, handling challenges, and cost of PM, 60 + 30+30 + 4 t ha-1PM is recommended. Therefore, for better growth and yield of maize, after the initial application of PM, UF application should be split-applied in accordance with plant growth and the pattern of uptake to avoid losses by leaching and therefore ensured that N level in the soil is high at the critical stage of N demand.

Effect of Biochar on Soil Properties, Soil Loss, and Cocoyam Yield on a Tropical Sandy Loam Alfisol.

Among agricultural soil amendment that can enhance crop productivity and soil sustainability is biochar. Hence, two-year field experiments were conducted on a sandy loam Alfisol at Owo, southwest Nigeria, to evaluate the effects of biochar produced from hardwood on soil physical and chemical characteristics, erosion potential, and cocoyam (Xanthosoma sagittifolium (L.) Schott) yield. The study was a 2 × 4 factorial experiment with two years (2017 and 2018) and four biochar levels (0 (control), 10, 20, and 30 t ha-1). The treatments were laid out in a randomized complete block design with three replications. Results indicated that biochar application significantly in both years improved yield of cocoyam and soil physical (bulk density, porosity, moisture content, mean weight diameter (MWD) of soil aggregates, dispersion ratio, and infiltration rate) and chemical (soil organic matter, pH, N, P, K, Ca, Mg, and CEC) properties and erosion resistance. Soil characteristics and cocoyam yield improved with level of biochar from 0-30 t ha-1. When 2018 is compared with 2017 in term of soil loss, in the amended plots, 2018 reduced soil loss by 7.4, 20, and 73.5%, respectively, for 10, 20, and 30 t ha-1biochar, whereas there was an increase of 2.7% soil loss in the control plot in 2018 compared with 2017. Therefore, application rate of 30 t ha-1 biochar is considered as suitable for severely degraded soil because this application rate efficiently improves cocoyam yield and soil properties and reduces soil loss.

MgO Fertilizer Sole and Combined with Organic and Inorganic Fertilizers: Effect on Soil Chemical Properties, Turmeric Performance, and Quality in a Tropical Alfisol.

For soil fertility maintenance, secondary nutrient such as Magnesium (Mg) is always being neglected. However, its role is critical in the growth, yield, and quality of crops. Therefore, two field experiments were initiated in 2017 and 2018 to evaluate the response of soil chemical properties, performance, and qualities of turmeric (Curcuma longa L.) to Mg fertilizer alone and in combination with poultry manure (PM) and NPK 15-15-15 fertilizer (NPK). The treatments applied were the following: (i) PM alone at 8 t ha-1, (ii) NPK alone at 200 kg ha-1, (iii) Mg fertilizer alone (in form of MgO) at 20 kg ha-1, (iv) PM at 8 t ha-1 with MgO at 20 kg ha-1 (PM + Mg), (v) NPK at 200 kg ha-1 with MgO at 20kgha-1 (NPK + Mg), and (vi) control (no amendment of any kind). PM, NPK, and Mg fertilizers alone or NPK + Mg and PM + Mg increased soil chemical properties, performance (plant height, number of leaves, number of tillers, number of rhizomes, and fresh rhizome weight), and minerals and vitamins C and A contents of turmeric rhizome compared with the control. By averaging 2017 and 2018, Mg fertilizer alone increased the yield of turmeric by 10.8% compared with the control. For this experiment, NPK + Mg increased growth and yield of turmeric compared with other treatments. Also, averaging 2017 and 2018, NPK + Mg increased rhizome yield of turmeric by 13.6% and 10.6% compared with PM + Mg and NPK alone, respectively. Similarly, PM + Mg significantly improved mineral and vitamins contents compared with other treatments. Therefore, for those that desire turmeric rhizome for its nutritive value, PM + Mg is recommended. For those that want quantity, NPK + Mg is recommended.