Fertilizer Management Practices Research Articles

Rice-Based Cropping System Effect on Yield and Yield Attributes on Promising Released Sesame Varieties

A field experiment was carried out at Agricultural College farm, Bapatla district, Andhra Pradesh, during the period from March 2023 to June 2023 to assess the performance of Sesame (Sesamum indicum L.) varieties under different fertilizer management practices in rice-based cropping system in Krishna Zone of AP. The experiment was laid out in a randomized block design with the factorial concept and three replications. The results showed that YLM 146 recorded significantly the highest seed yield (748 kg ha-1) at harvest. The yield attributing characters like the number of capsules plant-1 (67) and the number of seeds capsules-1 (45) were found significantly to be the highest in the variety YLM 146. Concerning different fertilizer management practices, 125% RDF + 1% foliar spray of 19:19:19 at the early budding and capsule formation stages recorded significantly higher seed yields (827 kg ha-1). Yield attributes like number of capsules plant-1 (96) and number of seeds capsules-1 (51) were significantly highest in 125% RDF + 1% foliar spray of 19:19:19 at the early budding and capsule formation stages. Overall, the results showed that sowing of YLM 146 variety with 125% RDF + 1% foliar spray of 19:19:19 at the early budding stage and early capsule formation stage seems to be appropriate for getting higher seed yield in Krishna Zone of Andhra Pradesh.

Modeling Nitrogen Fate and Water and Nitrogen Use Efficiencies under Different Greenhouse Vegetable Production Systems Using the WHCNS-Veg Model.

Quantitative evaluation of the effects of diverse greenhouse vegetable production systems (GVPS) on vegetable yield, soil water consumption, and nitrogen (N) fates could provide a scientific basis for identifying optimum water and fertilizer management practices for GVPS. This research was conducted from 2013 to 2015 in a greenhouse vegetable field in Quzhou County, North China. Three production systems were designed: conventional (CON), integrated (INT), and organic (ORG) systems. The WHCNS-Veg model was employed for simulating vegetable growth, water dynamics, and fates of N, as well as water and N use efficiencies (WUE and NUE) for four continuous growing seasons. The simulation results revealed that nitrate leaching and gaseous N emissions constituted the predominant N loss within GVPS, which separately accounted for 11.5-59.4% and 6.0-21.1% of the N outputs. The order of vegetable yield, N uptake, WUE, and NUE under different production systems was ORG > INT > CON, while the order of nitrate leaching and gaseous N loss was CON > INT > ORG. Compared to CON, ORG exhibited a significant increase in yield, N uptake, WUE, and NUE by 24.6%, 24.2%, 26.1%, and 89.7%, respectively, alongside notable reductions in nitrate leaching and gaseous N loss by 67.7% and 63.2%, respectively. The ORG system should be recommended to local farmers.

Nitrogen and phosphorus mineralization and their corresponding monetary values under long‐term integrated soil fertility management practices

Nitrogen and phosphorus mineralization and their corresponding monetary values under long‐term integrated soil fertility management practices

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.

Factors influencing small holder farmers adoption of climate SMART agriculture practices in Welmera Woreda, Central Ethiopia

Adoption of climate-smart agriculture practices are believed to have significantly lessened the devastating impact of climate change on agriculture. However, in countries like Ethiopia, the adoption and use level of climate-smart agriculture practices remains low. The understanding of farmers’ levels of CSA practice adoption and influencing factors is therefore crucial. The goal of the study is to evaluate the degree to which various CSA practices were being used in the study area, as well as adoption determinants. The study was conducted in Welmera district, Oromia, Ethiopia. Three kebeles were chosen from the district, and a random sample of 306 farmers was picked. We used a cross-sectional household survey, a focus group discussion, and interviews with key informants. A multivariate probit model was employed to investigate the factors influencing the adoption of multiple climate-smart agriculture practices. According to the result, conservation agriculture, integrated soil fertility management, and crop diversification are the most often used CSA practices. The results also revealed that male farmers outperformed female farmers in terms of crop diversity and improved animal feed and feeding practice adoption. The age of farmers has a considerable and unfavorable impact on their likelihood of adopting improved soil fertility management and crop diversification practices. However, it has a positive and considerable impact on the adoption of agroforestry practices. With regards to economic factors, having a relatively big farmland area considerably enhances the adoption of conservation agriculture, enhances soil fertility management and crop diversity, and improves livestock feed and feeding methods and post-harvest technology practice. Improved livestock feed and feeding are more likely to be used with higher farm income. Having a significant number of animals strongly promotes the adoption of conservation agriculture, and access to financial services positively impacts agroforestry, diversification of crops, and postharvest technology practice adoption. Furthermore, institutional factors including access to agricultural extension services and training were discovered to be important and beneficial for crop diversification; similarly, access to field day participation was discovered to have a significant and positive impact on the adoption of conservation agriculture and improved soil fertility management practices. It is critical to raise awareness about climate change among farmers and experts, as well as to incorporate location-specific CSA practices into agricultural programs.

Assessment of nutrient flows in maize-based farming system by smallholder farmers for sustainable production in Ikara, Kaduna State

Nutrient depletion is one of the major causes of decreased crop yield, and a threat to food security and sustainable crop production. NutMon- toolbox was used to determine nutrient flows and partial nutrient balances of maize-based smallholders’ farming system. Data was collected using structured questionnaire from 15 randomly selected farmers, with five farmers each in three villages. Composite soil samples were also taken from each of the three plots. At crop maturity, samples of crop products and residues were randomly taken from the selected fields. Nitrogen, P and K contents in soil and crop material was used to calculate nutrient flows and partial balances. Results obtained revealed that mineral fertilizer flow, averaged 349.20kg N yr-1 and 81.45kg K yr-1 and were lower than 376.65kg N yr-1 and 431.44kg K yr-1 organic input. However, phosphorus in mineral fertilizer (55.78kg P yr-1) was higher compared to phosphorus (51.06 kg P ha-1 yr-1) in organic input. Nitrogen, phosphorus and potassium for maize seeds and crop residue were all negative. The partial nutrient balances were positive 53.45kg N ha-1 yr-1 and 79.40kg K ha-1 but negative 1.10kg P ha-1 yr-1. Harvesting of crops for food, without incorporation of crop residue into the soil, were the most important sources of nutrient mining in smallholder production system. Integrated soil fertility management practices that favour the buildup of soil organic matter and use of animal manure should be encouraged through effective extension services at Ikara, Kaduna State, Nigeria.

The effects of straw return on soil bacterial diversity and functional profiles: A meta-analysis

Returning straw directly to agricultural fields increases soil carbon sequestration and influences soil microbial activities. However, the precise impacts of straw return on soil bacterial diversity, composition, and function profiles remain unclear, necessitating a comprehensive synthesis and standardized analysis. In this study, we conducted a meta-analysis of 729 original bacterial sequencing samples from fields with and without straw return to elucidate how soil bacteria respond to different experimental conditions after straw return (e.g., straw and fertilizer management practices and return duration). Our analysis revealed that overall straw return slightly increased the Chao 1 index while the Shannon index remained unaffected. However, we found strong responses depending on the experimental conditions of straw return. Particularly, bacterial community diversity increased significantly, particularly under high nitrogen, low straw addition, or continuous straw return. Furthermore, straw return altered bacterial community composition, elvating the abundance of Proteobacteria and Bacteroidetes, while decreasing Chloroflexi, Firmicutes, and Nitrospirae. Straw return also increased modularity in bacterial co-occurrence networks. Functional annotation analysis highlighted that straw return substantially enriched microbes involved in chemoheterotrophy, nitrogen fixation, and functional groups related to straw decomposition (chitinolysis, cellulolysis, xylanolysis), while inhibiting microbes associated with nitrification and nitrate reduction. Surprisingly, straw return did not impact the relative abundance of plant pathogens. Overall, our findings offer an in-depth understanding the effects of straw return on soil bacterial communities, including increased diversity, modified structure, and enhanced functional profiles related to straw decomposition.

Nitrogen deficiency in maize fields of the Southern Pampas does not affect kernel number but reduces weight per kernel.

Nitrogen (N) requirement of maize has been increasing over the past decades, but there has been a lack of adjustment in fertilization management practices across different regions in Argentina. The higher N requirement in modern hybrids is associated with a higher post-flowering N accumulation. Additionally, soil fertility in the Argentina Pampas has consistently decreased in recent years. Whether the effects of N deficiency are expressed in the post-flowering period is still unclear at field level. The objective of this work was to quantify the yield reduction attributed to N deficiency and to identify the physiological basis of this effect at the field level for typical high-tech farms across the south-eastern Pampas of Argentina. Nineteen experiments were conducted during the 2020/2021 growing season in the south-eastern Pampas, evaluating two N managements i) Farmers' N level; ii) High N input. Results showed that the additional N input increased grain yield by an average of 6.4% (average grain yield difference of 712 kg ha−1). Weight per kernel was the only yield component that responded to N fertilization. Farmers' N management did not affect N accumulation or growth-related variables such as leaf area index, green leaves per plant, PAR interception, nitrogen sufficiency index until flowering, but the farmers' N level reduced these variables during the grain filling period leading to differences in aerial biomass and N accumulated at physiological maturity. Farmers' N level led to decreased post-flowering N uptake during grain filling period, which reduced the photosynthetic capacity of the canopy. These findings suggest that N management strategies and models need to be reviewed for high-tech maize systems.

Organic Fertilizers and Bio-Waste for Sustainable Soil Management to Support Crops and Control Greenhouse Gas Emissions in Mediterranean Agroecosystems: A Review

Agriculture is facing several challenges related to its sustainability. In this regard, the need to reduce its environmental impact related to the use of synthetic inputs and its potential role in mitigating global warming and climate change call for a review of crop management. In this context, and in the framework of achieving sustainable development goals, the use of organic fertilizers and bio-waste represents a valuable contribution to the agricultural transition towards a bioeconomy model by reducing the negative impacts of waste disposal. Farmyard manure, composts, digestate from agrifood processes, and biochar are, among organic fertilizers, commonly used to manage soils and support crop growth. These fertilizers can provide essential nutrients, improve structure, and enhance microbial activity, thus increasing soil fertility and agriculture sustainability. While organic fertilizers offer the benefits of soil fertility and plant nutrition, their impact on greenhouse gas (GHG) emissions is complex and varies depending on factors such as fertilizer type, soil conditions, and management practices. Although organic fertilizers may initially increase GHG emissions, they often lead to carbon sequestration in soils highlighting a negative C balance. Additionally, organic fertilizers promote a reduction in fossil fuel consumption used for synthetic fertilizer production, further contributing to GHG emissions’ reduction. Therefore, while organic fertilizers pose challenges in managing GHG emissions, their various benefits warrant careful consideration and strategic implementation in agricultural systems.

Integrated Soil Fertility Management Practices for Coffee in Tanzania: A Review

Integrated Soil Fertility Management Practices for Coffee in Tanzania: A Review

Review on physiological and ecological characteristics and agronomic regulatory pathways of intercropping to delay root-canopy senescence of crops

Intercropping has been widely used in arid and semi-arid regions because of its high yield, and stable productivity, and efficient utilization of resources. However, in recent years, the high yield of traditional intercropping is mainly attributed to the large amount of purchased resources such as water and fertilizer, plastic film, and mechanical power. It leads to the decline of cultivated land quality and the phenomenon of premature root-canopy senescence of intercrops is become increasing serious. So, the application of traditional intercropping faces major challenges in crop production. In this paper, the manifestations, occurrence mechanisms, and agronomic regulatory pathways of crop senescence were analyzed in detail. The physiological and ecological characteristics of intercropping to delay root-canopy senescence of crops are reviewed in this paper. The main agronomic regulatory pathways of intercropping to delay root-canopy senescence of crops are based on above- and blow-ground interactions, include collocation of crop varieties, spatial arrangement, water and fertilizer management, and tillage and mulch practices. Future research fields of intercropping to delay root-canopy senescence should focus on the aspects of selecting and breeding special varieties, application of molecular biology techniques, and developing or applying models to predict and evaluate root-canopy senescence process of intercrops. Comprehensive analysis and evaluation of different research results could provide a basis for enhancing intercropping delay root-canopy senescence through adopting innovative technologies for regulating physio-ecological characteristics of intercrops. This would provide support for the development and adoption of high-yield, efficient, and sustainable intercropping systems in arid and semi-arid areas with more people and less land, and abundant light and heat resources.

Ketersediaan Nitrogen pada Ultisol dengan Aplikasi Kotoran Walet dan Arang Kayu

The application of organic matter with a high nitrogen (N) content in combination with the application of wood charcoal is a common soil fertility management practice in Ultisols. This study aims to determine the availability of N in Ultisols, which are applied to swallow droppings and wood charcoal. The experimental design used was a two-factor Completely Randomized Design (CRD), with the first factor being swallow droppings (0.5 and 10 t ha−1) and the second factor being wood charcoal (0, 10, and 20 t ha−1), with as many as three repetitions. As much as 200 g of soil was put into the incubation site, then swallow droppings and wood charcoal were added according to the treatment, stirred until evenly distributed, and then incubated at 70% field capacity for 14 days. The contents of NH4+, NO3-, and pH were observed at the end of the incubation period. The results showed that the application of swallow droppings and wood charcoal increased the content of NH4+, NO3-, and mineral N but lowered soil pH. The best treatment was given to swallow manure at 10 t ha-1 which increased mineral N by 59%, and a combination of swallow manure 10 t ha-1+10 t ha-1 wood charcoal which increased nitrate content by 1,666%. The results of this study indicate that the application of swallow droppings combined with wood charcoal can increase the availability of N in Ultisols.

Understanding the Perspectives of Small-Scale Arable Crop Farmers on Soil Management Practices in Uhen L.G.A, Edo State

This study provides insights into the perceptions of small-scale arable crop farmers in Uhen L.G.A regarding soil management practices. A total of 50 questionnaires were administered to randomly selected farmers and the questionnaires covered various aspects, including demographics, farming and soil fertility management practices, awareness of organic agriculture, soil health, and soil fertility, as well as acceptance, viability, and sustainability of organic inputs. The findings revealed that the majority of the respondents were male, with a range of ages and educational backgrounds, mostly attaining secondary education with varying levels of farming and agricultural experience. Regarding farming and soil fertility management practices, respondents reported adopting practices such as tillage, mound/heaps/ridges, bush burning, mulching, and mixed cropping. Organic fertilization was more commonly used than inorganic fertilization, with reasons cited including availability, low cost, crop response, and long-term effects. Farmers recognized the importance of organic residue and soil organisms for soil health. However, there was limited awareness of organic agriculture among the respondents, and their knowledge of soil organisms and their contributions to soil health was moderate. The findings highlight the need for increased awareness and knowledge of organic agriculture and the potential benefits of organic inputs for soil health and fertility.

Seasonal nitrate variations, risks, and sources in groundwater under different land use types in a thousand-year-cultivated region, northwestern China

The global public health concern of nitrate (NO3−) contamination in groundwater is particularly pronounced in irrigated agricultural regions. This paper aims to analyze the spatial distribution of groundwater NO3−, assess potential health risks for local residents, and quantitatively identify nitrate sources during different seasons and land use types in the Jinghuiqu Irrigation District, a region in northwestern China with a longstanding agricultural history. The investigation utilizes hydrochemical parameters, dual isotopic data, and the Bayesian stable isotope mixing model (MixSIAR). The findings underscore significant seasonal variations in the average concentrations of NO3−, with values of 87.72 mg/L and 101.87 mg/L during the wet and dry seasons, respectively. Furthermore, distinct fluctuations in nitrate concentration were observed across different land use types, whereby vegetable lands manifested the maximum concentration. Prolonged exposure to elevated nitrate concentrations may pose potential health risks to residents, especially in the dry season when the non-carcinogenic groundwater nitrate risk surges past its wet season counterpart. The MixSIAR analysis revealed that chemical fertilizers accounted for the majority of nitrate pollution in vegetable lands, both during the dry season (49.6%) and wet season (41.2%). In contrast, manure and sewage contributed significantly to NO3−concentrations in residential land during the wet (74.9%) and dry seasons (67.6%). For croplands, soil nitrogen emerged as a dominant source during the wet season (42.2%), while chemical fertilizers prevailed in the dry season (38.7%). In addition to source variations, the nitrate concentration of groundwater is further affected by hydrogeological conditions, with more permeable aquifers tending to display higher nitrate concentrations. Thus, targeted measures were proposed to modify or impede the nitrogen migration pathway, taking into consideration hydrogeological conditions and incorporating domestic sewage, organic fertilizer, and agricultural management practices.

Physical Properties and Crop Performance of Four Substrate Fibers in Greenhouse Petunia Production

As peat (P) demand increases throughout the horticultural industry, alternative fibers must be evaluated. Sugarcane bagasse (B), wood fiber (W), and coconut coir (C) have received interest as domestically available alternatives to P, with demonstrated success in producing greenhouse crops. However, there is limited research comparing these materials to peat. This research evaluated the substrate properties and productivity of Petunia Supertunia Mini Vista ‘Indigo’ in pine bark substrates amended with C, W, B, or P and fertigated weekly at 100, 200, or 300 parts per million (ppm) nitrogen (N) to account for possible N immobilization. The container capacity was lowest and air-filled porosity was highest in W and B substrates. Substrate pH increased in W and B substrates, and C substrates were fertigated at 100 ppm N. Increasing the N rate increased the growth index in all substrates, especially B and W substrates later in the production period. Higher fertilization increased shoot mass, chlorophyll content, and blooms across all substrates, demonstrating that fertilizer supplementation may offset possible N immobilization. While plant growth and quality parameters were greatest in the P blend, increasing N applications produced similar-quality plants using alternative substrates, demonstrating that modifying fertilizer management practices can make alternative fibers a viable horticultural substrate.

Agronomic efficiency and productivity of transplanted kharif rice (Oryza sativa) as influenced by fertilizer briquettes

An experiment was conducted during rainy (kharif) season of 2022 at the research farm of Assam Agricultural University, Jorhat, Assam to evaluate the effect of fertilizer briquettes on growth and productivity of transplanted rice. The field experiment was laid out in RBD comprising of 13 treatments, replicated thrice. Growth of rice, panicles/m2 and yield were subjected to significant variation under different fertilizer management practices. Higher plant height, tillers/ m2, panicles/m2, yield and agronomic efficiency were recorded under FDP, 120% RDN + 100% P and K + ZnSO4 @10 kg/ha + biofertilizer (T12). This might be owing to reduced losses of nutrients and efficient uptake by plants compared to broadcasted method of fertilizer application where most of the applied fertilizers were susceptible to various losses availing lesser amount of nutrients for crop uptake.

Substituting Partial Chemical Fertilizers with Bio-Organic Fertilizers to Reduce Greenhouse Gas Emissions in Water-Saving Irrigated Rice Fields

Conventional water and fertilizer management practices have led to elevated greenhouse gas emissions from rice fields and decreased the efficiency of water and fertilizer utilization in agricultural land. The implementation of water-saving irrigation and the substitution of chemical fertilizers with organic alternatives can influence CH4 and N2O emissions in rice fields. However, it remains unclear how the simultaneous application of both methods will affect the CH4 and N2O emissions in rice fields. Therefore, two irrigation methods (F: flooded irrigation; C: controlled irrigation) and three fertilization modes (A: full chemical fertilizer; B: bio-organic fertilizer replacing 15% chemical nitrogen fertilizer; C: bio-organic fertilizer replacing 30% chemical nitrogen fertilizer) were set up through field experiments to explore the effect of greenhouse gas emission reduction in rice fields by combining controlled irrigation and bio-organic fertilizers. Substituting some chemical fertilizers with bio-organic fertilizers can lower the peak CH4 and N2O fluxes in rice fields, leading to a decrease in the cumulative CH4 and N2O emissions by 11.9~29.7% and 10.8~57.3%, respectively. The reductions led to a considerable decrease in the global warming potential (GWP) and the greenhouse gas emission intensity (GHGI) by 16.1~48.1% and 16.3~48.1%, respectively. Controlled irrigation significantly reduced CH4 emissions by 55.2~69.4% compared with flooded irrigation in rice fields. However, it also increased N2O emissions by 47.5~207.9%, considerably reducing their GWPs by 11.8~45.5%. Neither bio-organic fertilizer substitution nor controlled irrigation significantly affected rice yield. Replacing 15% of chemical nitrogen fertilizers with bio-organic fertilizers in controlled irrigation rice fields can minimize rice GWP and GHGI. The study’s results are of significant importance for enhancing the regulation of greenhouse gases in farmland and achieving sustainable agriculture through cleaner production.

Effect of tillage, fertilizers and storage structures on quality shelf life of white yam (Dioscorea rotundata Poir) in south west Nigeria

This study examined the effect of tillage, fertilizers and storage structures on quality shelf life of white yam in South West Nigeria. The study was a factorial experiment consisting of Tillage, Fertilizers and Storage Structure. The tillage system involved Heap Tillage (HT) and Ridge Tillage (RT), while Fertilizers involved Poultry Manure (PM), N15P15K15 (NPK) and Control (CLT) and two types of Storage Structures namely; Traditional Barn (TB) and Open Sided Storage Structure (OSSS) were combined to form the treatments. The experiment was a 2x3x2 factorial combination arranged in a Randomised Complete Block Design (RCBD). The treatments were replicated three times for each location respectively. A total of 72 ridges and 144 heaps were used to make a population of 288 plants per location. The tubers were weighed to ensure uniformity before planting. The plot size was 18mx18m square with a pathway of 1.0m between blocks making a total of 324 square metres. At harvest, the tubers were weighed immediately. They were then kept separately in the two storage structures namely: Traditional Barn (TB) and the Open Side Storage Structure (OSSS) for a period of 3 months. After the 3rd months of storage, the tubers were examined and data collected. The weight of each tuber from each storage structure was taken periodically to evaluate the weight loss and assess the keeping quality periodically. The findings of this study demonstrated the significant influence of tillage, fertilizers, and storage structures on the quality, shelf life, nutrient use efficiency, and nutrient composition of white yam. Excessive fertilizer application was found to increase rotting and deterioration levels. Hence, farmers and stakeholders should carefully consider fertilizer application rates to minimize post-harvest losses and enhance food security. Further investigations are needed to explore the underlying mechanisms responsible for the observed effects and to optimize fertilizer management practices for yam storage. Organic fertilization enhances the nutrient use efficiency and nutritional quality of yam, while appropriate storage structures, play a crucial role in preserving the quality and extending the shelf life of the harvested tubers. Based on the result of the study, open sided storage should be considered by producers of yams for storing their harvested tubers due to the facts that, it performed well in minimizing nutrient lost, weight loss and decay to considerable level and prevented pests/rodents attack on yam tubers.

New phosphorus losses via tile drainage depend on fertilizer form, placement, and timing.

Agricultural phosphorus (P) losses are harmful to water quality, but knowledge gaps about the importance of fertilizer management practices on new (recently applied) sources of P may limit P loss mitigation efforts. Weighted regression models applied to subsurface tile drainage water quality data enabled estimating the new P losses associated with 155 P applications in Ohio and Indiana, USA. Daily discharge and dissolved reactive P (DRP) and total P (TP) loads were used to detect increases in P loss following each application which was considered new P. The magnitude of new P losses was small relative to fertilizer application rates, averaging 79.3g DRP ha-1 and 96.1g TP ha-1 , or<3% of P applied. The eight largest new P losses surpassed 330g DRP ha-1 or 575g TP ha-1 . New P loss mitigation strategies should focus on broadcast liquid manure applications; on average, manure applications caused greater new P losses than inorganic fertilizers, and surface broadcast applications were associated with greater new P losses than injected or incorporated applications. Late fall applications risked having large new P losses applications. On an annual basis, new P contributed an average of 14% of DRP and 5% of TP losses from tile drains, which is much less than previous studies that included surface runoff, suggesting that tile drainage is relatively buffered with regard to new P losses. Therefore old (preexisting soil P) P sources dominated tile drain P losses, and P loss reduction efforts will need to address this source.

Fertilizer use efficiency and economic viability in maize production in the Savannah and transitional zones of Ghana

Increasing fertilizer use is highly justified for sustainable agricultural intensification if yield response, fertilizer use efficiency (FUE), and economic viability of fertilizer application are high. Despite the increasing fertilizer application rates in Ghana, yields only marginally increased. Also, the recent fertilizer price hikes post COVID-19 revived concern for economic analysis of fertilizers. This study analyzed the FUE and economic viability of fertilizer use in maize production in Guinea/Sudan Savannah and Transitional/Deciduous zones of Ghana. Survey data from 2,673 farmers in the 2019, 2020, and 2021 production seasons were used. The average agronomic efficiency (AE), partial factor productivity (PFP), and value-cost ratio (VCR) of fertilizer use were 2.2 kg of grains per kilogram of fertilizer, 18.3 kg grains per kilogram of fertilizer, and 1.8 Ghana cedis of marginal yield per Ghana cedi spent on fertilizer, respectively. Fertilizer use was economically viable for only 28.1% of farmers with a VCR of 2 or higher, while 52.5% reached the break-even point with a VCR of at least 1. Various fertilizer formulations, including NPK plus sulfur, and adoption of integrated soil fertility management (ISFM) practices, particularly improved seeds, organic fertilizers, and minimum tillage, improved maize yield response to fertilizer and thus the FUE. These low efficiency and economic viability of fertilizer use are prevailing conditions in other sub-Saharan Africa (SSA) countries and these do not guarantee sustainable food security and improved livelihood of the farmers in the region. Ghana’s Ministry of Food and Agriculture (MoFA), together with relevant stakeholders, should provide guidance on ISFM and intensify farmer education through farmer associations to increase the adoption of ISFM. The local government should work with other relevant stakeholders to improve the market conditions within the agriculture sector, for instance, by linking farmers to city markets for favorable output prices.