Soil Fertility Management Strategies Research Articles

The rhizosphere bacterial community of water yam (Dioscorea alata L.) under limited water conditions

AbstractIntroductionYam cultivation in West Africa, the largest yam production area, has expanded to the northern Guinea savanna, which receives an annual rainfall of 800–1000 mm. However, variations in rainfall are problematic for the stable productivity of yams. Integrated soil fertility management is urgently needed to improve and stabilise yam productivity. Plants have complex interactions with bacterial communities, influencing their health and environmental adaptability. Although the growth of water yams (Dioscorea alata L.) at various rainfall levels might be related to their interaction with the bacterial community, their structure under water limitation is yet to be elucidated. Here, we evaluated the bacterial community structure in the rhizosphere (Rh) and roots of ‘A‐19’ under water limitation conditions.Materials and MethodsPlants were grown under normal conditions, and watering was reduced to less than 70% for 1 month. Rh and root samples were collected for DNA extraction, and downstream amplicon sequencing analyses were performed.ResultsThe dry weight of the shoots, particularly the leaves, decreased under water limitation. Bacterial diversity in the rhizocompartments was significantly reduced. However, bacterial community composition was not affected by water limitation. Despite water‐limited conditions, bacterial community structure was robust in the Burkholderia‐Caballeronia‐Paraburkholderia and Streptomyces clades. These taxa accounted for approximately 60% of the relative abundance in the roots under water limitation.Conclusionidentifying bacterial community composition of ‘A‐19’ under water‐limited conditions provides fundamental information for developing integrated soil fertility management strategies across rainfall gradients in West Africa. Our study indicates that ‘A‐19’ has a robust bacterial community structure for beneficial interactions with bacteria despite soil water conditions.

Optimizing sunflower production through the use of GIS-based soil fertility management strategy

Optimizing sunflower production through the use of GIS-based soil fertility management strategy

Modeling the response of sesame (Sesamum indicum L.) to different soil fertility levels under rain-fed conditions in the semi-arid areas of western Tigray, Ethiopia

Sesame, a crucial oilseed crop in Ethiopia, ranks second only to coffee in its importance as an exported agricultural commodity. However, inadequate soil fertility management has hampered its productivity despite its substantial international market demand. Hence, this study was conducted to model the response of sesame to different nitrogen fertilizer levels using the AquaCrop model, and to assess the capability of the model as a decision-support tool for optimizing soil fertility management strategies in the study area. The experiment was laid out in a randomized complete block design, consisting of four nitrogen fertilizer rates (0, 23, 46, and 69 kg/ha nitrogen) and three distinct sesame varieties (Setit-1, Setit-2, and Humera-1). Over the course of the three cropping seasons, data on soil physical and chemical properties, crop growth, yield and yield components were collected for each treatment. Evaluation of model performance relied upon established metrics of coefficient of determination (R2), root mean square error (RMSE), normalized root mean square error (N-RMSE), model efficiency (E), and degree of agreement (D). Analysis of results revealed the AquaCrop model appropriately calibrated for simulation of soil water content, showing R2 values ranging from 0.92 to 0.98, RMSE values varying from 6.5 to 13.9 mm, E values from 0.78 to 0.94, and D values from 0.95 to 0.99. Similarly, simulation outputs for aboveground biomass (AB) demonstrated good accuracy of the model, with R2 values varying from 0.92 to 0.98, RMSE values ranging from 0.33 to 0.54 tons/ha, and D values from 0.9 to 0.98. Notable accuracy was also observed in the simulation of canopy cover (CC), revealing R2 values between 0.95 and 0.99, and RMSE values ranging from 5.3 to 8.6 %. In conclusion, this study substantiates the successful calibration and validation of the AquaCrop model for predicting sesame response to diverse nitrogen fertilizer levels. The performance of the model in predicting soil water content, CC, AB, and yield highlights its potential as a valuable tool for optimizing soil fertility management and enhancing sesame cultivation practices in Ethiopia.

Farmers’ Perception and Practice of Soil Fertility Management and Conservation in the Era of Digital Soil Information Systems in Southwest Nigeria

This study assessed the perception and use of digital applications for soil fertility management and conservation strategies among small-scale crop farmers in southwest Nigeria. A total of 376 farmers were randomly selected across the six southwest states. The data collected were analyzed using descriptive statistics. The majority of the farmers relied on perception and other non-scientific approaches such as the appearance of weeds and performance of crops in the previous season to assess soil fertility. Only 1.1% and 0.3% of the farmers assessed soil fertility through soil tests and digital applications, respectively. Most farmers adopted bush fallowing and the use of inorganic fertilizers to improve soil fertility. Although 4.8% of the farmers indicated that they had digital applications on their mobile phones, only 2.9% claimed to have used these. More than half (56.4%) of the farmers stated that a lack of awareness of the existence of digital applications and internet-enabled telephones were the reasons they have not been able to use digital applications. The majority of the farmers (97.3%) indicated their willingness to embrace the use of new farm decision digital applications which could provide more information, especially on soil fertility, if introduced. More extensive services focusing on older, less literate farmers and farmers who hitherto did not belong to any farmers’ association are advocated for in order to encourage the use of digital applications and soil fertility management and conservation practices.

Perception and Characterization of Integrated Soil Fertility Management Strategies as a Technique for Adaptation to Climate Change In Northern of Benin

Perception and Characterization of Integrated Soil Fertility Management Strategies as a Technique for Adaptation to Climate Change In Northern of Benin

Resource endowment and sustainable soil fertility management strategies in maize farming systems in northern Benin

IntroductionManaging soil fertility remains one of the major concerns of smallholder farmers in Sub-Saharan Africa (SSA). In order to understand the adoption potential of recommended practices to smallholders, this study aimed to characterize the resource availability, allocation and use patterns, and the soil fertility management practices in the maize farming system in northern Benin.MethodsA survey was conducted with 262 households randomly selected across three municipalities from three agro-ecological zones. Focus groups discussions and individual interviews were conducted with the household heads using an interview guide and a structured questionnaire respectively. The main data collected included (a) the socio-economic characteristics of households, (b) the main farm type and their characteristics and (c) the current soil fertility management strategies and the rationale behind.Results and discussionThe main soil fertility practices included the use of mineral fertilizer, manure, and crop residues application to plots. As a general trend, the rates of fertilizers applied by farmers [on average 132 ± 8.5 and 59 ± 5.8 kg ha−1 of Nitrogen-Phosphorus-Potassium (NPK) and urea] were below those recommended or required to ensure optimal maize yields. Five farm types corresponding to different resource endowments or wealth classes were identified. The scarce resource farms owned by the majority of poorer farmers use only small amounts of manure and fertilizer in their fields. Qualitative analysis indicated that farms have different constraints and opportunities to adopt newly proposed soil fertility management recommendations.ConclusionExtension services and decision makers must target specific interventions for appropriation and sustainability of technologies to resource mostly the smallholder farmers.

Assessment of soil fertility and nutrient management strategies in calcareous soils of Khuzestan province: a case study using the Nutrient Index Value method.

Soil fertility (SF) is a crucial factor that directly impacts the performance and quality of crop production. To investigate the SF status in agricultural lands of winter wheat in Khuzestan province, 811 samples were collected from the soil surface (0-25cm). Eleven soil properties, i.e., electrical conductivity (EC), soil organic carbon (SOC), total nitrogen (TN), calcium carbonate equivalent (CCE), available phosphorus (Pav), exchangeable potassium (Kex), iron (Fe), copper (Cu), zinc (Zn), manganese (Mn), and soil pH, were measured in the samples. The Nutrient Index Value (NIV) was calculated based on wheat nutritional requirements. The results indicated that 100%, 93%, and 74% of the study areas for CCE, pH, and EC fell into the low, moderate, and moderate to high NIV classes, respectively. Also, 25% of the area is classified as low fertility (NIV < 1.67), 75% falls under medium fertility (1.67 < NIV value < 2.33), and none in high fertility (NIV value > 2.33). Assessment of the mean wheat yield (AWY) and its comparison with NIV showed that the highest yield was in the Ramhormoz region (5200kg.ha-1), while the lowest yield was in the Hendijan region (3000kg.ha-1) with the lowest EC rate in the study area. Elevated levels of salinity and CCE in soils had the most negative impact on irrigated WY, while Pav, TN, and Mn availability showed significant effects on crop production. Therefore, implementing SF management practices is essential for both quantitative and qualitative improvement in irrigated wheat production in Khuzestan province.

Quantitative analysis of soil degradation in response to land use change in the Guinea savanna zone of Ghana

Soil degradation (SD) poses a significant challenge to tropical agricultural production systems due to its role in depleting soil nutrients. Recently, SD has threatened population growth by causing hunger and poverty among smallholder farmers in the Guinea savanna agro-ecological zone of Ghana. However, SD cannot be directly measured. Instead, assessment and modelling efforts rely on biological and physico-chemical indicators. This study sought to: (i) select a minimum dataset (MDS) using a multivariate statistical technique; (ii) identify SD processes, and evaluate the extent of degradation; and (iii) suggest strategies to monitor SD in the study area. Soil samples were collected using the Land Degradation Surveillance Framework (LDSF), specifically designed for sub-plot level (1000 m2) sampling. This scheme aligns well with the typical farm structure of smallholder farmers (<10 acres). Soil samples, taken from a depth of 0–20 cm, were analyzed to assess their physico-chemical properties. Principal component analysis (PCA) identified seven key SD processes: soil texture, pH, organic carbon (OC), total nitrogen (TN), available phosphorus (Av. P), base saturation (BS) and Effective Cation Exchange Capacity (ECEC). These identified processes lead to the loss of OC, deterioration of soil texture, reduction in soil nutrients, and increased soil acidity. There was a strong positive correlation (r = 0.70, p<0.05) between soil physical and chemical properties. PC1 explained 26.86% of the total variance, followed by PC2 at 15.31%, PC3 at 12.46%, and PC4 at 9.98%. Also, PC5, PC6, and PC7 accounted for 8.49%, 7.25% and 1.42% of the variance, respectively. The land-use systems we identified significantly affected the concentration of soil nutrients (p<0.001). In our computed Composite Soil Degradation Index (CSDI), CEC emerged as the most significant SD indicator with a weight of 0.328, followed by Si:CL ratio at 0.187. The results indicate that soil management activities should focus on increasing organic matter. Soil nutrient depletion primarily occurs through several processes. Land clearing and burning of organic materials during land preparation are primary causes. Furthermore, a total crop removal during harvest, inadequate manure application, and subsequent leaching and erosion aggravates SD, leading to nutrient-depleted soils. We conclude that the loss of nutrients, specifically CEC, OC, Ex. K and Av. P is the primary contributor to chemical SD. Therefore, implementing integrated soil fertility management (ISFM) strategies, such as applying organic (e.g., animal-based manures, green manure, crop residues, compost) and inorganic fertilizers (e.g., NPK + micronutrients) is crucial for increasing soil nutrient availability, enhancing SOM content, and promoting carbon sequestration in these farming systems. This study establishes a baseline for comparing and evaluating the effectiveness of land management interventions at the landscape level in northern Ghana. Consequently, soil nutrient management should be tailored to site-specific conditions, focusing on increasing the efficiency of N, P, K and micronutrient uptake by plants. Adopting such site-specific management strategies could significantly contribute to the sustainable intensification of agricultural production systems in the Guinea Savanna agro-ecological zone of Ghana.

Fertility Assessment of Nun River Floodplain Soils in Bayelsa State, Southern Nigeria for Agricultural Productivity

Following massive crude oil exploitation in Bayelsa State, arable land is shrinking and a food crisis, looming. To stop this trend, information on soil fertility status and management strategies becomes important for policy development. This paper assesses fertility status of the Nun River floodplain soils in Bayelsa State using newly developed indices for sustainable agricultural productivity and food security. Nun River plain alluvial soils of different landforms were collected from the genetic horizons of nine profiles, and analysed for physicochemical characteristics and soil fertility assessed using soil fertility index. (SFI) and soil evaluation factor (SEF). ). Silt-sized particles dominated Odi (ODI), Koroama (KRM) and Niger Delta University (NDU 1) soils, except in NDU2 and NDU3, pH was moderate to slightly acidic (5.64–6.30), available P, low to high (0.6–22 mg/kg), organic C (0.31–5.35%), and total nitrogen (0.01–0.45%) low to high while calcium dominated the exchange complex. Correlation between Organic matter and total N (r = 0.366, p ‹ 0.001) and available P (r = - 0.310, p ‹ 0.01) was highly positively, suggesting that organic matter dictates availability of N and P. The SFI values were higher (p ‹0.05) than SEF except in NUD2 and NDU3, pH, organic matter and available phosphorus contributing more. Of paramount importance is conservation of organic matter as the accumulation of biomass greatly improved physical properties and fertility of the soil.

Climate change awareness and adaptation strategies by smallholder farmers in semi-arid areas of Zimbabwe

ABSTRACT Agricultural production, food, nutrition and income security of smallholder farmers in sub-Saharan Africa are threatened by extreme weather events, such as increased frequency of mid-season dry spells and increased temperatures. Their impacts are exacerbated by the prevalence of sandy soils, characterized by limited water and nutrient retention capacity leading to low crop productivity. In this study, we aimed at assessing farmers' awareness of extreme weather events, identify adaptation strategies and evaluate maize yield from different soil fertility and water management practices. A household survey including 245 smallholder farmers in Marange, Zimbabwe was carried out. The results revealed that farmers were aware of and had experienced extreme weather events. Among adaptation strategies used were soil water-harvesting, use of improved varieties, mulching and planting trees. Maize yield remains significantly low, averaging 0.62 t ha−1 among farmers using some forms of soil fertility and water management strategies. To further understand the reason for low maize yields and improve climate change related adaptation strategies, more research is needed to quantify and confirm management practices applied by farmers, such as fertilizer use and rates, water and nutrient management, use of improved varieties as well as socio-economic factors.

Integrated soil fertility management using cocoa bean shells improves soil chemical properties, coconut yield and mitigates environmental pollution

One approach to sustain and intensify coconut production is nutrient cycling through an integrated soil fertility management strategy. This strategy may include transferring crop by-products from one farm commodity to another. One such promising by-products identified is cocoa bean shells (CBS), which is in abundance and could serve as an environmental pollutant at Bamiankor, which is a forest zone and an important area for coconut and cocoa productions, located in the Western region of Ghana. Following this, a 42-month integrated soil fertility management field study was conducted to assess improvements in selected soil chemical properties, coupled with vegetative, and reproductive parameters in a Sri Lankan Green Dwarf (SGD) coconut genotype under various fertilizer treatments. The treatments included: no-fertilizer control (CK), nitrogen-phosphorus-potassium (NPK) fertilizer, cocoa bean shells (CBS), and NPK+CBS, which were arranged in a randomized complete block design (RBCD) in three replications. There were appreciable increases in values of soil pH, total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), and available phosphorus (AP). Values in carbon to nitrogen (C:N) ratio after treatment with CBS, however, were significantly reduced. It was observed that collar girth from palms treated with NPK+CBS were significantly higher compared to other treatments. Similarly, number of leaves, percentage of palm inflorescence, and number of nut-load palm−1 year−1 were all significantly higher under NPK+CBS treated palms compared to the other treatments. In conclusion, CBS in combination with NPK fertilizer is recommended as a good strategy to intensify coconut production. However, for a long-term benefit, circularity, cleaner, and sustainable production, addition of sole CBS is advocated. Adoption of this management strategy will also potentially mitigate the negative environmental consequences associated with accumulation of CBS in studied area.

Measuring integrated smallholder soil fertility management practices in Megech watershed, Tana sub-basin, Ethiopia

Nowadays, a combination of natural and man-made factors has led to a decline in the physical and chemical quality of the soil. In Ethiopia, declining soil fertility and quality that lead to low agricultural production are made worse by soil erosion and nutrient depletion. Adoption and implementation of integrated soil fertility management strategies have emerged as inevitabilities in terms of development in Ethiopia generally and in the Tana sub-basin of northwest Ethiopia specifically. This study was created to evaluate the Megech watershed's integrated smallholder soil fertility management methods' adoption factors, status, and scope. A total of 380 individual farmers were surveyed using a semi-structured questionnaire to gather primary data. Descriptive statistics and econometric estimating methods were combined in the study. The findings supported the use of inorganic fertilizer, tree planting, organic fertilizer, stone bunds, and soil bunds by households as the primary methods for managing soil fertility. The outcomes of the econometric model also show that households' adoption decisions for integrated soil fertility management practices are highly interdependent. Additionally, there were similar underlying factors that affected the status and intensity of implementing integrated soil fertility management practices. The research concluded that effective soil management policies and programs should be designed, and implemented by smallholder farmers, agricultural experts, research centers, and governmental and non-governmental organizations to improve the quality of soil for sustainable food production. Moreover, raising the affordability of financial services and strengthening smallholder farmers' access to education help to increase their income, which in turn encourages the use of integrated soil fertility management practices.

Effects of Liming on Acid Ferrasols for Sustainable Crop Production in Uganda – A Review

Ferralsols are the predominant soil type covering about 70% of the total land area of Uganda; they are mostly found in the Central and Western regions of the country. Ferralsols are highly weathered, acidic and have inherently low nutrient reserves. Degradation of these soils has led to reduced agricultural production and productivity. Despite the increased human population and the importance of Agriculture to the majority of the households in Uganda, little or no research has been carried out on Acid Ferralsols to improve food security and sustain livelihoods. Besides, the country’s research programs have not prioritized the use and management of soil fertility management strategies such as liming. Crop yields on these soils are often far less than those on research stations. This review paper focuses on the extent and effects, causes, challenges and opportunities associated with liming Acid Ferralsols and the effects on soil properties and crop yield. Many studies have shown that detrimental effects of acid soils can be ameliorated through liming, thus improving on the physio-chemical properties to improve crop production and yield. More research is anticipated to develop lime requirements for acid Ferralsols so as to meet the growing food demand in Uganda.

Diversity of soil fertility management options in maize-based farming systems in northern Benin: A quantitative survey

Introduction: Maize-based production systems in Sub-Saharan Africa are largely based on family farming, which is characterized by low-input, nutrient-mining agriculture and practices. These systems usually promote soil degradation through loss of organic matter and erosion. The present study characterizes farms and main soil fertility management options in maize-based farming systems of the northern Benin.Methods: The study was conducted in the municipalities of Malanville, Banikoara and Bembèrèkè. We sampled randomly and interviewed 262 maize farmers, and the statistical analysis (distribution of means and frequencies, chi-square, ANOVA, etc.) was performed.Results and discussion: The results show that maize farming characteristics and socioeconomic conditions (land use and labor, production activities and land allocation, institutional arrangements on land, access to labor and capital, etc.) were diverse across locations and exhibited a wide variation within locations. Several practices were used for the management and sustainable maintenance of soil fertility in maize production systems in northern Benin: maize-legume intercropping, cotton-maize rotation, and mineral and organic fertilizers application. Most of farmers occasionally or regularly used mineral fertilizers (95.4%), followed by legume-cereal rotation/ intercropping (51.9%). Overall, 23.6% and 58.4% of farmers consistently used mineral fertilizer over the last 5 and 10 years, respectively. The amount of applied mineral fertilizer did not significantly vary between locations with an average (applied day after sowing, DAS) of 131.7 ± 13.7 (22 ± 8 DAS), 58.7 ± 9.6 (44 ± 5 DAS) and 164.7 ± 25.4 (38 ± 11 DAS) kg ha−1 for NPK, urea and Mix NPK + urea, respectively applied at, and days after sowing. Most farmers spread the fertilizer around the plants without covering with soil particles. Manure was applied exclusively to food crops through transporting and corralling (28.2%); and most farmers also used manure from their own livestock while few farmers used cattle corralling. Farmyard manure was mainly spread (100% of respondents) on the surface before plowing at the beginning of the rainy season. Maize farmers applied mineral fertilizer based on the level of initial soil fertility (naturally fertile or poor, degree of erosion etc.) and fertilizer purchase costs. Manure was not widely used as an alternative to chemical fertilizers; therefore, farmers need more strengthening and technical assistance on the production of organic fertilizers and manure storage. The findings are useful for policymakers on encouraging the successful implementation of sustainable soil fertility management strategies of maize-based farming systems in northern Benin.

Combined Effects of Indigenous Arbuscular Mycorrhizal Fungi (AMF) and NPK Fertilizer on Growth and Yields of Maize and Soil Nutrient Availability

The excessive application of mineral fertilizers in maize cultivation leads to progressive soil contamination in the long term and increases the cost of production. An alternative to reduce over-fertilization is to perform a partial replacement with microbes that promote nutrition and growth, such as Arbuscular Mycorrhizal Fungi (AMF). A pot experiment which was followed by two field experiments was performed with and without the application of indigenous AMF in combination with five nitrogen–phosphorus–potassium (NPK) fertilization rates (100% NPK = N120P60K60; 75% NPK = N90P45K45; 50% NPK = N60P30K30; 25% NPK = N30P15K15; control = N0P0K0). The objective was to investigate whether the soil application of indigenous mycorrhizal fungi inoculum combined with NPK fertilization can provide higher maize yields and soil-available N, P, and K than chemical fertilization can alone. The greenhouse results showed that the application of AMF with a 50% NPK treatment significantly increased the plant’s growth, root colonization, leaf chlorophyll content, and N, P, and K tissue content. The results from the field conditions showed that there was a highly significant yield after the treatment with AMF + 50% NPK. The study also revealed that mycorrhizal fungi inoculation increased the available soil N and P concentrations when it was combined with a 50% NPK dose. This suggests that the inoculation of fields with AM fungi can reduce the chemical fertilizer application by half, while improving soil chemistry. The results suggested that AMF inoculation can be used in integrated soil fertility management strategies.

Estimating acid soil effects on selected cereal crop productivities in Ethiopia: Comparing economic cost-effectiveness of lime and fertilizer applications.

Acid soils are a major constraint to agricultural productivity in many parts of sub-Saharan Africa, including Ethiopia. Restoring soil pH to optimal ranges for agriculture can have a significant impact on yields, particularly for acid intolerant crops like wheat and barley. The application of agricultural lime is the standard corrective, although the large application requirements, lack of farmer awareness, and weak or non-existent lime supply chains make this a complex problem to address at scale. To date, no large-scale farmer trials of lime application have been undertaken in Ethiopia. This leaves open the question to local policy makers as to the economic benefits given the enormous capital and logistics investments required. To help address this we leverage existing spatial edaphic data and longitudinal crop surveys to simulate the productivity impact of varying lime and fertilizer applications. Our estimates find the impact of moving pH from 5.5 to 6.5, modeled as a lime soil remediation strategy, increases yields by 22% and 19% for wheat and barley, respectively. In addition, at lower pH levels our models indicate that commonly used nitrogen-based fertilizers are less cost-effective. For wheat in highly acidic soils, we find that fertilizers cost over two times as much as a single application of lime over a five-year period. The cost savings of the use of lime reaches as high as 121% of average one-year agricultural household income for wheat; with barley these savings are lower but still substantial at 24%. In general, we advocate for an integrated soil fertility management strategy that applies appropriate levels of fertilizer on pH balanced soil. If successful, Ethiopia's acid soil reclamation could become a modest version of Brazil's successful "cerrado miracle" and serve as an example for Africa.

Organic Carbon Content in Fractions of Soils Managed for Soil Fertility Improvement in Sub-Humid Agroecosystems of Kenya

Soil health and fertility are indexed by soil organic carbon (SOC) content. Soil management through good agricultural practices that enhance and sustain SOC is vital for soil fertility. We examined the influence of soil fertility management strategies on SOC concentrations in different particle size fractions under a maize cropping system. We laid the experiment in a randomized complete block design, with 14 treatments replicated 4 times, and used the following inputs: inorganic fertilizer (Mf), maize residue +inorganic fertilizer (RMf), maize residue + inorganic fertilizer, and goat manure (RMfM), maize residue + goat manure + Dolichos Lablab L intercrop (RML), maize residue + Tithonia diversifolia + goat manure (RTiM) and maize residue + Tithonia diversifolia + phosphate rock (Minjingu) (RTiP) and a Control (no inputs) under reduced tillage (Mt) or conventional tillage (Ct). Soil samples were collected from two depths, 0–5 cm, and 5–15 cm. We determined the content of organic carbon in three physical fractionation: coarse fractions (1.7 mm, 500 µm sieve), medium fractions (250 µm and 90 µm), and a fine fraction (75 µm). Results showed that treatment with maize residues, goat manure, and legume intercrop (MtRML and CtRML) resulted in higher SOC in most fractions, irrespective of the soil depth. The SOC concentration significantly (p &lt; 0.0001) differed across treatments and depth. It was followed by maize residue, goat manure, and inorganic fertilizer treatments, and the least was inorganic fertilizer treatment. This underpins the importance of manure application and crop residue retention in increasing SOC amounts. Reduced tillage did not influence the SOC amounts during the sampling period in the experimentation site. This study highlights the possibility of improving agricultural productivity by improving soil fertility through a combination of different agricultural soil fertility amendments in Sub-Saharan Africa.

Good agriculture practices for safe food and sustainable agriculture in Nepal: A review

Food safety is a growing concern worldwide but is especially prevalent in Nepal. Agriculture is the country's critical economic sector, and its sustainability is challenged due to the increasing use of agrochemicals. As a result, low Soil Organic Matter (SOM), reduced crop productivity, increased food safety hazards, and negative impacts on human health and the environment are reported in the agriculture sector in Nepal. In 2018, the concept of Good Agriculture Practices (GAP) was introduced in Nepal to address the issues of food safety, trade, and sustainability. As GAP is relatively new to Nepal, it is still broad and ambiguous, which makes its use and implementation difficult. For this purpose, we conducted a literature review on available global evidence to present the benefits of GAP and to identify the critical barriers to the adoption of GA. The review shows GAP's potential to increase crop yield by up to 36%, reduce agrochemicals use by 31%, increase SOM from a mean of 3.32%–3.77%, and increase farmers' income by more than 100%. However, the review has also identified barriers to wider adoption of GAP, broadly categorized into production, extension, regulation and standards, and markets and finance. The valuable outcome of this review is that it proposes five key pathways: (i) Technical capacity building, (ii) Awareness creation, (iii) Soil fertility management strategies, (iv) Extension programs, and (v) Market development for institutionalizing GAP in Nepal, based on the learning from global evidence. This review could be useful for policymakers and the government of Nepal to develop detailed implementation guidelines for GAP, including appropriate policies as well as short, medium, and long-term plans and programs for institutionalizing GAP in Nepal. • Aimless use of agrochemicals is challenging the agriculture sustainability in Nepal. • GAP reduces agrochemicals use by 31%, and increase SOM from a mean 3.32%–3.77%. • GAP increases crop yield by up to 36% and farmers' income by more than 100%. • Several barriers to broader adoption of GAP in developed and developing countries. • Five key pathways are proposed for institutionalizing GAP in Nepal.

Nitrogen uptake and grain yield of maize (Zea mays L.) as influenced by soil amendments of neem (Azadirachta indica L.) cake and oil extracts and NPK fertilizer in Guinea savannah zone of Ghana

Maize (Zea mays L.) has high response to N and the efficient uptake of N is a major factor influencing grain yield. The effect of inorganic NPK fertilizer and Neem cake and neem oil as soil amendments were examined on maize N uptake and grain yield. A 3 × 3 × 2 factorial experiment was laid out in a Randomized Complete Block Design with three replications at the University for Development Studies farms at Nyankpala near Tamale, in northern Ghana. The treatments consisted of combinations of three levels of neem cake (0, 200 and 400 kg ha-1), three levels of neem oil (0, 10 and 20 L ha-1) and two levels of NPK (0 and 250 kg ha-1). The results showed that NPK at 250 kg ha-1 combined with neem cake at 400 kg ha-1 significantly (p &lt; 0.05) increased N uptake in maize by 31% (from 111.3 kg ha-1 to 146.9 kg ha-1) compared to the recommended NPK rate. Maize grain yield was significantly maximized by that treatment at 7,471 kg ha-1. Grain yield was significantly associated with N uptake; therefore 250 kg ha-1 NPK with 400 kg ha-1 neem cake could be recommended for maize farmers in the project area. In contrast, neem oil extracts significantly reduced N uptake. The results of the study posited important implications for soil fertility management and climate change mitigation strategies for enhanced maize production.

Organic and bio-fertilizer inputs in coffee production system, coffee cultivation constraints and the role of coffee in coffee cultivation sectors: A review

Coffea arabica L. is the most traded commodity and the principal source of revenue for coffee cultivation sectors in Ethiopia and its market has been growing from time to time. With the demand changing, use and consumption of natural products has been growing, so there has been greater interest in research in this area. Added to this interest, is the concern of environmental impact caused by chemical inputs. Soil fertility management strategies for improving plant nutrients and crop productivity include the use of application of composts, vermicomposts and manures, and application of bio fertilizer or microbial inoculants. Bio-fertilizer technologies can contribute to efficient utilization of limited resource of phosphorus fertilizers under low-input farming systems and guarantee the environment for livelihood. Therefore, they are a good alternative for the so called perennial field crop production organically; because in addition to their numerous activities, they have low cost, and are sustainable, safe and effective. The application of efficient phosphate-solubilizing microbial inoculants in agriculture opens up new insight for future crop productivity besides sustaining soil health. The purpose of this review is to raise potential applications of organic and bio-fertilizer inputs in coffee production system to sustain organic coffee cultivation and to elucidate the main obstacles for yield reduction in the coffee production sectors. In this regard this review has also shown that phosphate-solubilizing microbes (PSMs) have tremendous potential as bio-fertilizers. This review also contains information on coffee consumption custom in Ethiopia and its role in cultural systems. Finally, this review focuses on relevant research performed and success in using bio-inoculants during the last decade that can help us improve sustainable coffee production.