Crop Nutrient Use Research Articles

An Overview of N2O Emissions from Cropping Systems and Current Strategies to Improve Nitrogen Use Efficiency

Arable soils significantly contribute to atmosphere pollution through N2O emissions due to the massive use of N-based fertilizers and soil managements. N2O formation in the soil occurs mainly through nitrification and denitrification processes, which are influenced by soil moisture, temperature, oxygen concentration, pH, and the amount of available organic carbon and nitrogen. This review synthetically presents the mechanisms of N2O formation and emission in arable land and some of the current strategies to improve crop nutrient use efficiency. Biological nitrification inhibitor-based agronomic strategies are also presented as future prospects for the sustainable management of crops, which is missing in most of the reviews.

Nanotech for Fertilizers and Nutrients-Improving Nutrient use Efficiency with Nano-Enabled Fertilizers

The development of nano-enabled fertilizers presents new opportunities to improve crop nutrient use efficiency and reduce environmental impacts of agriculture. Nanoparticles, nano capsules, and nano clays can be engineered to control the release rate of nutrients to better match crop demands over time. Slow-release nano fertilizers may enhance nutrient absorption by plants while mitigating nutrient losses to the environment. Additionally, nano fertilizers can facilitate co-delivery of nutrients, growth regulators, and pesticides, allowing for more precise crop management practices. This review synthesizes current research on synthesis techniques, characterization methods, and agronomic testing results for a range of nano fertilizer products. Key nutrient carriers reviewed include mesoporous silica nanoparticles, layered double hydroxides, cellulose nanocrystals, and halloysite nanotubes loaded with nitrogen, phosphorus, potassium, and micronutrients. Release kinetics depend on nano fertilizer composition, size, and shape, as well as environmental conditions. Field studies indicate positive impacts of nano fertilizers on crop yield, nutrient use efficiency, and pest resistance compared to conventional fertilizer formulations. However, questions remain regarding large-scale feasibility, economic viability, environmental fate, and biological impacts of nano-enabled fertilizers. Ongoing interdisciplinary research across the domains of materials science, agronomy, ecology, and economics is required to develop nano fertilizers that maximize production efficiency while minimizing risks.

Rhizospheric compensation of nutrient cycling functions dominates crop productivity and nutrient use efficiency

The influence of fertilization on crop nutrient use efficiency (NUE) and productivity remain unclear. Here, to assess how fertilization management influences the soil microbial communities and their functional profiles and consequently affects NUE and crop productivity, we established a field experiment with mineral and combined organic-mineral fertilization as well as mineral fertilizer reduction practices. The composition of the microbial community was measured by high-throughput amplicon sequencing, and its functional profile was predicted using PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) software. Our results demonstrated that fertilization management significantly shifted the rhizosphere bacterial community and regulated the compensation intensity of nutrient cycling-related functions, which means the rhizosphere bacterial community assembles to harbour greater nutrient cycling-related functions in lower available nutrient conditions to meet the nutrient requirements of the host plant. Moderate compensation intensity of nutrient cycling functions contributed to the highest NUE and crop productivity being achieved in the combined organic-mineral fertilization treatment. However, insufficient fertilizer input induced intense functional compensation, while standard mineral fertilizer input resulted in weakened functional compensation of nutrient cycling functions, both of which decreased NUE and crop productivity. Overall, this study provides new insights into the key roles of the rhizosphere microbiome in improving NUE, and suggests that the functional compensation characteristics of the rhizosphere microbial community may be a sensitive indicator of nutrient supply and demand relationships as well as a predictor of NUE.

Sweet basil can be grown hydroponically at low phosphorus and high sodium chloride concentration: Effect on plant and nutrient solution management

Agronomic inputs in agriculture easily exceed crop needs causing environment pollution. Phosphorus (P) is a macronutrient largely used in agriculture as a mineral fertilizer that requires an accurate management because it is a finite and non-renewable resource. Growing plants hydroponically can optimize plant nutrition achieving high crop nutrient use efficiency. However, irrigation water of poor quality (saline) interferes with crop performance. In this study, the effects of different P and NaCl levels in the root zone were evaluated on basil plants grown in a deep liquid culture system in a growth chamber. Two experiments with different P (from 0.1 to 1.0 mol m−3) and NaCl (from 0 to 60 mol m−3) concentrations in the nutrient solution were carried out. Plant growth, leaf gas exchanges and fluorescence, uptake of minerals and water, and leaf quality (content of minerals and pigments, and antioxidant capacity) were analysed. The most relevant morphological plant response to the low P (i.e., roughly 0.1 x of a standard nutrient solution) concentration consisted in a greater root/shoot ratio. However, plants growing at low P concentration did not show any reduction in yield and quality. Sodium chloride did not significantly affect plants yield and quality up to a concentration of 30 mol m−3 confirming the tolerance of basil to moderate saline stress. Significant reduction in the total biomass, water uptake and photosynthesis instead occurred at NaCl 60 mol m−3. These results confirmed the hypotheses that basil can be grown hydroponically at low P and high NaCl concentration with proper management of the nutrient solution. The absence of significant interactions between P and NaCl suggests that these two factors can be managed independently with potential benefits for crop economic and environmental sustainability.

Facile synthesis of nanomaterials as nanofertilizers: a novel way for sustainable crop production.

Nutrient fertilization plays a major role in improving crop productivity and maintaining soil fertility. In the last few decades, the productivity of current agricultural practices highly depends on the use of chemical fertilizers. Major drawback of traditional fertilizers is their low crop nutrient use efficiency and high loss into water. Nanomaterial in agriculture is a multipurpose tool for increasing growth, development, and yield of plants. Nanotechnology facilitates the amplifying of agriculture production by reducing relevant losses and improving the input efficiency. Nanotechnology has emerged as an attractive field of research and has various agriculture applications, especially the use of nano-agrochemicals to increase nutrient use efficiency and agricultural yield. Nanofertilizers are more effective as compared to chemical fertilizers due to their cost-efficient, eco-friendly, non-toxic, and more stable in nature. Overall, this chapter focuses on synthesis of nanofertilizers through physical, chemical, and biological methods. This chapter will also explore the use of nano-enabled fertilizers to enhance the nutrient use efficiency for sustainable crop production, and global food safety.

Biochar Tablets with and without Embedded Fertilizer on the Soil Chemical Characteristics and Nutrient Use Efficiency of Zea mays

Densification of ashy biochar into tablet can enhance the handling and conveyance efficiencies of biochar. It was hypothesized that fertilizer-embedded biochar tablets can slowly release embedded nutrients in synchrony with optimum nutrient uptake by crops. The objectives of this research were to determine the effects of biochar tablets with and without embedded fertilizer on soil chemical properties and nutrient use efficiency of Zea mays (sweet corn). The biochar tablet (BT) was produced by blending a biochar mixture with starch followed by densification using a single punch tablet press whereas the fertilizer embedded biochar tablet (BF) was prepared using the same procedure except that NPK fertilizer was added during blending. A pot experiment with five fertilization treatments including control was carried out in an open field located in Perlis, Malaysia. Co-application of biochar and fertilizer increased soil total carbon, nitrogen, but it reduced soil electrical conductivity (EC). Additionally, the BF significantly increased leaf chlorophyll content, dry root weight, and total plant nutrient use efficiency of sweet corn. The findings suggest that BF can serve as a slow release fertilizer to improve crop nutrient use efficiency. Therefore, embedding fertilizer in biochar tablets is recommended for sweet corn production following a long term field study to confirm the findings of this pot study.

Deconstructing agronomic resource use efficiencies to increase food production

Food production per unit land area needs to be increased, thus cropping systems need to use nutrients, water and solar radiation at as close to maximal efficiencies as possible. We deconstruct these efficiencies into their components to define a theoretical crop ideosystem, in which all resource use efficiencies are maximised. This defines an upper biological limit to food production. We then quantify the difference between maximum use efficiencies and those observed in three agronomic systems (maize, cocksfoot, sugarcane) and identify how, in actual farm systems, efficiencies can be raised to raise food production. We find that crop nutrient use efficiency can be limited by low water availability; thus adding nutrients would not raise production but adding water would. The converse situation of water use efficiency being affected by nutrition is not as evident. Ideosystem thinking can be used to define small- and large-scale agronomic systems that optimize water and nutrient use to maximise food production. Highlights - Novel ideosystem method of analysing processes of food production, focussing on resource use efficiencies. - Interactions between resource use efficiencies are asymmetrical. - The ideosystem concept portrays how far a production system approaches maximum efficiency.

Regulating the nutrient release rates from proteinaceous agricultural byproducts using organic amendments and its effect on soil chemical and microbiological properties

Meat and bone meal (MBM) is a byproduct of the rendering industry and is considered an excellent potential organic fertilizer due to its balanced availability of nutrients. However, rapid nutrient mineralization of the MBM that is less synchronized with crop demand, could lead to significant nutrient losses, necessitating measures to modify the mineralization rates of MBM. Here we tested the influence of two natural nitrification inhibitors (NIs; neem cake and karanja cake) on the mineralization of carbon (C), nitrogen (N), and phosphorus (P) from MBM, the associated soil potential enzymatic activity, microbial abundance and broad composition and the influence of these process on plant growth. MBM mineralized quickly, with 35% mineralization of the applied N within the first 5 days of incubation. NIs reduced nitrification rate of MBM by ~ 40% and increased the retention of NH4+ (~ 35%) in soil compared with MBM only. Soil CO2 respiration, potential enzymatic activity and microbial abundance were similar in the MBM with and without NIs, suggesting a low negative effect of NIs on the microbial growth and functionality. MBM exhibits a slow P mineralization rate, with an increase in soil available P was observed only at later sampling points (36 days after incubation) with solubilization of a fraction of Ca-P. P mineralization rates were similar between the MBM with and without NIs. MBM with and without NIs was equally effective in maintaining the plant growth and biomass, which were similar to inorganic fertilizers. Our study suggests that MBM blended with NIs could increase the crop nutrient use efficiency via lowering N losses, while improving soil microbiological health.

Biosolids and biochar application effects on bahiagrass herbage accumulation and nutritive value

AbstractPastures represent the major cropping system where biosolids are recycled in Florida, yet limited information is available documenting the agronomic benefits of biosolids recycling programs. A 2‐yr experiment evaluated bahiagrass (Paspalum notatum Flügge) responses to application of biosolids and inorganic fertilizer applied either alone or in combination with biochar. Our hypothesis was that biochar could alter soil N and P dynamics, thus, affecting crop nutrient use efficiency. Treatments were a factorial arrangement of four fertilizer sources (inorganic fertilizer, thermally dried Class AA biosolids, aerobically digested Class B biosolids, and anaerobically digested Class B biosolids; surface‐applied at 160 kg plant available N ha−1 yr−1) with or without biochar (applied at 1% wt basis). Bahiagrass total annual herbage accumulation was similar for biosolids and inorganic fertilizer treatments in 2017; however, inorganic fertilizer and aerobically digested Class B biosolids increased total annual herbage accumulation by as much as ∼29% relative to other sources in 2018. Biosolids and inorganic fertilizer increased bahiagrass crude protein (CP) concentration by as much as ∼22 and ∼39% in 2017 and 2018, respectively, compared to unfertilized treatment. No treatment effects were observed on in vitro digestible organic matter (IVDOM) concentration in 2017; however, in 2018 biosolids resulted in greater IVDOM than inorganic fertilizer. Data suggested no benefit of biochar on bahiagrass responses. Bahiagrass tissue mineral concentrations in both biosolids and inorganic fertilizer treatments were generally within sufficient range for optimum plant growth. Biosolids can be a viable alternative for sustainable bahiagrass production while reducing the dependence on inorganic fertilizer.

Method for Preparation of Nutrient-depleted Soil for Determination of Plant Nutrient Requirements

ABSTRACTResearch for nutrient optimization and crop nutrient use efficiency requires precise control on soil nutrient status. While nutrient-depleted soils are preferable to artificial soils or hydroponics, reliable and affordable methods for nutrient removal are lacking. We report the systematic standardization and validation of a simple method to wash soil with purified deionized water for the removal of nutrients such as nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and organic carbon. Sandy soil was washed with RO water (1:1, w/v) followed by several washes with Type 1 ultrapure water (2:1, w/v) and tested after each wash for the removal of organic carbon, N, P, K, and Ca. After seven washes, total dissolved solids (TDS) were reduced to 5 ppm, conductivity to 10 µS, organic carbon content was reduced by 78%, while N by 19.5%, P by 30%, K by 48% and Ca by 29%. Two genotypes of rice were grown for full life cycle under normal and low N fertilizer (urea) levels to demonstrate that soil depleted with nutrients by our method supports normal plant growth in the greenhouse and allows experiments impossible under field conditions. Precise control on the nutrient status of the soil by our method also helped demonstrate yield differences between genotypes and N regimes and also that higher grain yields can be obtained with low nitrogen (N) input. Thus, our method facilitates better design of experiments for precise determination of nutrient requirements for crop growth and nutrient use efficiency.

Connecting Crop Nutrient Use Efficiency to Future Soil Productivity

Trends over the past 25 years indicate that Argentina’s growth in its grain crop productivity has largely been supported by the depletion of the extensive fertility of its Pampean soils. Long-term research provides insight into sustainable nutrient management strategies ready for wide-scale adoption.

THE INFLUENCE OF PLANT CO-CULTURE OF TOMATO PLANTS WITH PIRIFORMOSPORA INDICA ON BIOMASS ACCUMULATION AND STRESS TOLERANCE

In the face of increasing demand for crop production and the detrimental environmental impact of the excessive use of fertilizers it is important to use all available tools to increase crop nutrient use, efficiency and quality. Nutrient acquisition by the plant roots is much influenced by the microbial composition and activity of the rhizosphere. Most crop plants (80%) form symbiotic associations with arbuscular mycorrhizal fungi. However, these fungi are obligatory biotrophs, and therefore cannot be cultivated without the plants. Piriformospora indica is a recently discovered endophyte that mimics many of the effects of arbuscular mycorrhizal fungi but can be cultivated in axenic cultures. The aim of our work was to evaluate the effects of the co-culture of Piriformospora indica with tomato (Solanum lycopersicum 'Roma') plants in respect to plant response to stress and production quality. Results show that P. indica is able to promote resistance to stress (salt and nutrient) through the activation of antioxidant metabolism, which leads to the accumulation of ascorbate (vitamin C). Fruits of plants inoculated with P. indica maintain their lycopene content independently of the growth conditions.

Soil macrofauna affect crop nitrogen and water use efficiencies in semi-arid West Africa

It is increasingly recognised that soil fauna have a significant role in soil processes affecting nutrient availability and crop performance. A field experiment was conducted in southern Burkina Faso (West Africa) to investigate the contribution of soil fauna to nutrient availability and crop performance after application of different organic materials with contrasting qualities. A split plot design with four replications was laid out. The main treatment was the use of insecticides, to establish plots without fauna next to plots with fauna. The sub-treatments consisted in the application of Andropogon straw, cattle dung, maize straw, compost or sheep dung and a control. Soil fauna significantly increased crop water use efficiency. Crop nutrient use efficiency was high with the use of easily decomposable organic material in the presence of soil fauna. Supplementing low quality organic resources with mineral nitrogen is required to optimise the effects of their interaction with soil fauna towards enhanced crop nutrient and water use efficiencies.

Assessment of N, P and K management by nutrient balances and flows on peri-urban smallholder farms in southern Vietnam

There has recently been a strong tendency for agricultural production in peri-urban areas in southern Vietnam to move away from low input rice production to more intensive fruit and vegetable production, often in combination with pig production. The access to a market has led to increased availability of fertilisers and livestock feed in these areas, which has resulted in a dramatic increase in nutrient inputs. The objective of this study was to describe nutrient management on smallholder farming systems in a peri-urban area outside Ho Chi Minh City in southern Vietnam. Nutrient management was assessed by nutrient balances and flows and the data were gathered through interviews with local farmers, and measurement of inputs and outputs. Nine farms were selected containing one or more of the following production units: pig, crops, and fish. Feedstuffs and fertilisers were important sources of input of N, P and K on the livestock farms. On the farms without pig production, ash constituted on average 77% of all K input, but for N and P, fertilisers were the dominant forms of input. Farm-gate balances for N, P and K were positive on all farms and were in the range 31–868 kg N ha −1 per year, 23–644 kg P ha −1 per year and 9–770 kg K ha −1 per year. The different production units were poorly integrated as nutrient output from one unit seldom matched nutrient demand, as estimated by nutrient output, in the next unit. All pig production units showed similar nutrient use efficiencies, but there were large differences between the crop units, varying greatly both among different crops, and for the same crop, among the farms. The crop units were characterised by large nutrient surpluses and low nutrient efficiencies, indicating a high risk for nutrient losses to the wider environment. The results highlight the farmers' need for better tools to optimise farm nutrient management, both through better integration of the production units, but especially also by improving crop nutrient use efficiency.

A data base of crop nutrient use, water use, and carbon dioxide exchange in a 2O square meter growth chamber: I. Wheat as a case study.

A data set is given describing the daily nutrient uptake, gas exchange, environmental conditions, and carbon (C), and nutrient partitioning at harvest for the entire canopy and root system of a wheat crop (Triticum aestivum, cv. Yecora Rojo). The data were obtained from a 20 m2 stand of wheat plants grown from planting to maturity in a closed, controlled environment, and include daily nutrient uptake [macronutrients, nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S); and micronutrients, iron (Fe), boron (B), manganese (Mn), zinc (Zn), copper (Cu), and molybdenum (Mo)], canopy carbon dioxide (CO2) exchange rates, and transpiration. Environmental factors such as relative humidity, air temperature, nutrient solution temperature, pH and electrical conductivity, and photoperiod were controlled in the chamber to specific set points. A detailed description of biomass yield for each of the 64 plant growth trays comprising the 20 m2 of growth area is also provided, and includes dry weights of grain, straw, chaff, and roots, along with the concentration of nutrients in different plant tissues and the percent carbohydrate, fat, and protein. To our knowledge, this information represents one of the most extensive data sets available for a canopy of wheat grown from seed to maturity under controlled environmental and nutritional conditions, and thus may provide useful information for model development and validation. A methods section is included to qualify any assumptions that might be required for the use of the data in plant growth models, along with a daily event calendar indicating when adjustments in set points and occasional equipment or sensor failures occurred.