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Organic fertilizers have been used since the dawn of mankind to improve soil fertility and promote crop growth. However, the process of preparing organic fertilizers for use in agricultural activities is a labour-intensive and time-consuming procedure. Thus, in order to reduce labour costs and improve the efficiency of organic fertilizer preparation, automated organic fertilizer mixers were developed. For this research work, an improved organic fertilizer mixer based on the Internet of Things (IoT) technology capable of monitoring the status of fertilizer production remotely and providing updates and alerts to workers was developed. The aim of this work was to further reduce labour workload and costs, thus increasing efficiency of the organic fertilizer mixing process. In order to accommodate the IoT monitoring system, several modifications and design changes were carried out on the prototype of an automated organic fertilizer mixer. Tests conducted on the prototype unit showed that it performs as required. The IoT monitoring system successfully captures and uploads information on the weight of agricultural waste mixture in the storage drum to the IoT platform. This information can then be used to alert workers on when to add more agricultural waste material to the mixture or remove the processed organic fertilizer. Furthermore, an overall operational cost comparison of different organic fertilizer production methods showed that the automated organic fertilizer prototype provides operational cost savings of over 5 times when compared to current automated systems. Future work includes further automation to the agricultural waste filling and organic fertilizer removal process.

Estimating soil nitrogen (N) mineralization is critical to balance fertilizer N requirements and their environmental impacts. In this study, net N mineralization was examined in soils under different crop rotations with each phase of the rotation present every year with biologically based incubations in 2011 and 2015. Net N mineralization was significantly different among treatments when the current crop was soybean, and the effect was dependent upon the previous crop and the cropping sequence. In particular, net increases in inorganic N were greater when the previous crop was winter wheat with or without red clover than if it were corn, and greater for the first year of soybean compared with the second year for rotations with two consecutive years of soybean in the 2011 incubation. However, cropping history did not influence net soil N mineralization when the current crop was corn, winter wheat, or winter wheat with red clover. In 2015, the presence of red clover in the rotation increased net N mineralization in all phases of the rotation. These results suggest both current and previous crops should be considered when estimating the N supplying capacity (net mineralization) of the soil. Net mineralizable N was found to be significantly correlated with total amino sugars (P

Soil water repellency (SWR) was measured for a 28 yr field study under irrigation on a clay loam Dark Brown soil in southern Alberta. The objectives were to study the effect of legume–cereal crop rotations, feedlot manure, and phosphorus (P) fertilizer application on soil hydrophobicity (SH) and soil water repellency index (RI) under irrigation. Mean SH and RI were similar (P > 0.05) for a legume–cereal and cereal rotation and were unaffected by P fertilization. However, P fertilization shifted the RI classification from slight to subcritical. In contrast, SH was significantly greater for manured than nonmanured treatments, while RI was unaffected. Soil organic carbon (SOC) concentration was significantly (P ≤ 0.05) correlated with SH (r = 0.74), but not with RI (r = −0.17). This suggested a closer association between the quantity of SOC and quantity of hydrophobic compounds (SH method) compared with the hydrophobic coatings inhibiting infiltration of water (RI method). No significant correlation between SH and RI (r = −0.09) suggests that SH is not a good predictor of SWR using the RI method. Overall, manure application increased SH and P fertilization shifted the RI classification from slight to subcritical. In contrast, legume–cereal rotations had no influence on SH and SWR using RI method compared with continuous cereal.

The role of the tea commodity in the economy of Indonesia is quite strategic. Various types of microorganisms in nature have been known to increase the benefit of the root function, suppress disease, and accelerate plant growth. This study aimed to determine the potential of indigenous bacteria (Azoto II-1, Acinetobacter sp., bacteria Endo-5, bacteria Endo-65 and Endo-76) on the growth of tea plants and their potential in increasing resistance to blister blight disease. The test of microbes’ potential effect on growth and blister blight was conducted in Gambung, West Java in an experimental field using a randomized block design (RBD) with six treatments and each treatment was replicated four times. The composition of the treatments was: A) Endo-5; B) Endo-65; C) Endo-76; D) Azoto II-1; E) Acinetobacter sp.; and F) control (without microbes). Bacterial suspension was applied directly to the soil at a dose of 2 l · ha−1. The bacterial suspension was applied six times at 1 week intervals. The results of field observations indicated that the intensity of blister blight decreased in all treatments but did not significantly differ from the control. Meanwhile, the results of Acinetobacter sp. treatment in tea shoots was 17.26% higher than the control.

Nitrogen resulting from the mineralization of organic fertilizers is of great importance in organic farming and depends greatly on the type of fertilizer used. Two tests (incubation and pot test) were conducted on poor organic matter soil to assess mineralization and N release from different organic sources. The objective of the first test was the study of the mineralization under incubation conditions of four organic fertilizers commonly used doses (worm-compost: 5 t ha−1; compost: 5 t ha−1; sheep manure: 30 t ha−1; fishmeal: 3,5 t ha−1), while that of the second test was the study in pot experiment of the effect of adding worm-compost (0, 5, 10 and 15 t ha−1) and fishmeal (0, 1.75 and 3.5 t ha−1) on N mineralization, and growth and yield of potato. During incubation, N mineralized from the four organic fertilizers tested differ significantly. The maximum N mineralization apparent rates (NMAR) were 62.3%, 38%, 30% and 18%, for fishmeal, compost, worm-compost and sheep manure, respectively. At the end of the incubation, an N immobilization was observed for worm-compost and compost and was attributed to a C/N increase. For the pots test, the use of fishmeal had a significant effect on leaf number, plant height, plant dry matter, aerial nitrogen uptake, tuber number and tuber yield, while the addition of worm-compost had an effect, on leaf number and tuber yield only. The combination of these two fertilizers (10 t ha−1 of worm-compost and 1.75 t ha−1 of fishmeal) generated at harvest a maximum of underground N uptake (2.96 g plant−1; 123 kg ha−1) and total N uptake (3.26 g plant−1; 136.5 kg ha−1). This was favored by NMAR of 71% and 64.3% for fishmeal and worm-compost, respectively, generating the optimal yield (554.4 g plant−1; 23.1 t ha−1).

Spinach (Spinacia oleracea L.) is considered a nitrogen (N) intensive plant with high nitrate (NO3-) accumulation in its leaves. The current study via a two-year field trial introduced an approach by combining N fertilization from different sources (e.g., ammonium nitrate; 33.5% N, and urea; 48% N) at different rates (180, and 360 kg N ha-1) with the foliar spraying of molybdenum (Mo) as sodium molybdate, and/or manganese (Mn) as manganese sulphate at rates of 50 and 100 mgL-1 of each or with a mixture of Mo and Mn at rates of 50 and 50 mg L-1, respectively on growth, chemical constituents, and NO3- accumulation in leaves. Our findings revealed that the highest rate of N fertilization (360 kg N ha-1) significantly increased most of the measured parameters e.g., plant length, fresh and dry weight plant-1, number of leaves plant-1, leaf area plant-1, leaf pigments (chlorophyll a, b and carotenoids), nutrients (N, P, K, Fe, Mn, Zn), total soluble carbohydrates, protein content, net assimilation rate, and NO3- accumulation, but decreased leaf area ratio and relative growth rate. Moreover, plants received urea-N fertilizer gave the highest values of all previous attributes when compared with ammonium nitrate –N fertilizers, and the lowest values of NO3- accumulation. The co-fertilization of N-Mo-Mn gave the highest values in all studied attributes and the lowest NO3- accumulation. The best treatment was recorded under the treatment of 360 kg N-urea ha-1 in parallel with the combined foliar application of Mo and Mn (50+50mg L-1). Our findings proposed that the co-fertilization of N-Mo-Mn could enhance spinach yield and its quality, while reducing NO3- accumulation in leaves, resulting agronomical, environmental and economic benefits.

In rice-producing countries, the abundance of rice residue must be sustainably managed to avoid environmental problems. Moreover, repeated usage of inorganic fertilizers has caused rapid soil deterioration in these arable lands. Converting rice husk residue into rice husk biochar (RHB) and reapplying it back to paddy fields as a soil amendment can be a sustainable approach in rice production. Due to its adsorptive capability, nutrient retention capacity and high silica content, RHB can improve soil fertility and improving the effectiveness of fertilizer when mixed together due to its nutrient retention capacity and high silica content. High silica content in rice husk biochar provides better nutrient retention, turgidity, and structure for plant. The objectives of this review article are to compile studies related to rice husk biochar properties and factors affecting it and application of rice husk biochar in Asian agriculture.

Labor scarcity requires double-season rice to be planted by direct seeding as an alternative to transplanting. Only ultrashort-duration varieties can be used in direct-seeded, double-season rice (DSD) in central China where thermal time is limited. Whether ultrashort-duration varieties grown in DSD can be as productive and efficient in nitrogen (N) use as transplanted double-season rice (TPD) remains unclear. Field experiments were conducted in Hubei province, central China with two establishment methods (DSD, TPD) and three N rates in the early and late seasons of 2017 and 2018. Nitrogen treatments included zero-N control (N0), total N rate of 60 kg N ha−1 with equal splits at basal, midtillering, and panicle initiation (N1), and weekly N application at 15 kg ha−1 from seeding/transplanting to heading (N2). Both early- and late-season rice under DSD matured within 95 days, on average 9 days shorter than rice under TPD. The grain yield of DSD was comparable to or higher than that of TDP in both seasons, although the daily yield was significantly higher under DSD than under TDP. Before heading, DSD had higher leaf area, stem number, intercepted radiation, and radiation use efficiency than TPD, which compensated for the negative effect of short growth duration on biomass production. Total dry weight and harvest index under DSD were comparable to or higher than those under TDP. In general, the recovery efficiency of fertilizer-N under DSD was higher than that under TPD, but the reverse was true for physiological N use efficiency. Thus, there was no significant difference in agronomic N use efficiency between DSD and TPD. These results suggested that DSD with ultrashort-duration varieties is a promising alternative to TPD in central China for maintaining high grain yield and N fertilizer use efficiency with less labor input.

Scenedesmus obliquus ABC-009 is a microalgal strain that accumulates large amounts of lutein, particularly when subjected to growth-limiting conditions. Here, the performance of this strain was evaluated for the simultaneous production of lutein and biofuels under three different modes of cultivation - photoautotrophic mode using BG-11 with air or 2% CO2 and heterotrophic mode using YM medium. While it was found that the highest fatty acid methyl ester (FAME) level and lutein content per biomass (%) were achieved in BG-11 medium with CO2 and air, respectively, heterotrophic cultivation resulted in much higher biomass productivity. While the cell concentrations of the cultures grown under BG-11 and CO2 were largely similar to those grown in YM medium, the disparity in the biomass yield was largely attributed to the larger cell volume in heterotrophically cultivated cells. Post-cultivation light treatment was found to further enhance the biomass productivity in all three cases and lutein content in heterotrophic conditions. Consequently, the maximum biomass (757.14 ± 20.20 mg/L/d), FAME (92.78 ± 0.08 mg/L/d), and lutein (1.006 ± 0.23 mg/L/d) productivities were obtained under heterotrophic cultivation. Next, large-scale lutein production using microalgae was demonstrated using a 1-ton open raceway pond cultivation system and a low-cost fertilizer (Eco-Sol). The overall biomass yields were similar in both media, while slightly higher lutein content was obtained using the fertilizer owing to the higher nitrogen content of the medium.

Se establecieron dos experimentos en las mismas parcelas desde 1 de mayo a 1 de diciembre de 1991 y 1992 para determinar la extracción mensual de nutrimentos y producción de materia seca en el ñame 'Gunung'. En el primer año las plantas fueron abonadas a razón de 0; 667; 1,333; 2,000 y 2,667 kg/ha con un fertilizante 15-5-15-5 (N, P2O5, K2O y MgO) suplementado con elementos menores. El segundo año no se aplicó fertilizante. Se efectuaron seis cosechas de biomasa a los 2, 3, 4, 5, 6 y 7 meses después de la siembra. En cada cosecha las plantas fueron excavadas y separadas en láminas de hojas, tallos y peciolos, raíces y tubérculos. Se determinó el peso húmedo y seco de ios componentes de la planta y se obtuvieron muestras de tejido. Luego estas muestras se analizaron para determinar su contenido de N, P, K, Ca y Mg. Independientemente del año, los tratamientos de fertilizantes no afectaron significativemente el rendimiento en peso seco de los tubérculos mercadeables. La extracción máxima de nutrimentos fue 214 kg/ ha de N, 19 kg/ha de P, 223 kg/ha de K, 95 kg/ha de Ca y 9 kg/ha de Mg. La producción máxima de materia seca fue 11,303 kg/ha de los cuales 8,672 kg/ ha se acumularon en los tubérculos mercadeables. La extracción máxima de N, K, y Ca ocurrió a los cinco meses después de la siembra. La producción máxima de materia seca fue a los siete meses. Las plantas del ñame utilizaron 24.7 kg/ha de N, 2.2 kg/ha de P, 25.7 kg/ha de K, 11.0 kg/ha de Ca y 1.0 kg/ha de Mg por cada 1,000 kg/ha de materia seca comestible producida.

Water erosion process induces differences to the nitrogen (N) functional microbial community structure, which is the driving force to key N processes at soil-water interface. However, how the soil N transformations associated with water erosion is affected by microorganisms, and how the microbial respond, are still unclear. The objective of this study is to investigate the changes of microbial diversity and community structure of the N-cycle function microorganisms as affected by water erosion under application of organic manure and straw cover. On the basis of iso-nitrogen substitution, four treatments were set up: 1) only chemical fertilizer with N 150 kg ha−1, P2O5 60 kg ha−1 and K2O 90 kg ha−1 (CK); the N was substituted 20% by 2) organic manure (OM); 3) straw (SW); and 4) organic manure + straw (1:1) (OMSW). The results showed that applying organic manure and straw to sloping farmland can increase soil N contents, but reduce runoff depth, Kw, sediment yield and N loss, especially in the OMSW. Straw cover and straw + organic manure increased the diversity (Chao1) of nitrifier (AOB), and both diversity and uniformity (Shannon) of denitrifier (nirK/S) were increased in the OMSW. All erosion control measures reduced N-fixing bacteria diversity and increased their uniformity, and the combined application of organic manure and straw cover was a better erosion control measure than the single application of them. Improved soil chemistry and erodibility were the main drives for the changes of N-functional microbial community structure and the appearance of dominant bacteria with different organic materials.

The 100th anniversary of a leading nitrogen fixation technology developer like CASALE SA is a reason to reflect over the 20th century successful solution of the problem of world food supply, and to look out for solutions for sustainable developments with respect to ammonia production. We review the role of nitrogen as essential chemical constituent in photosynthesis and biology, and component of ammonia as it is used as fertilizer for primary production by photosynthesis for farming and food supply and its future role as energy carrier. While novel synthesis methods and very advanced synchrotron based x-ray analytical techniques are being developed, we feel it is important to refer to the historical and economical context of nitrogen. The breaking of the N N triple bond remains a fundamental chemical and energetic problem in this context. We review the electrochemical ammonia synthesis as an energetically and environmentally benign method. Two relatively novel X-ray spectroscopy methods, which are relevant for the molecular understanding of the catalysts and biocatalysts, i.e. soft X-ray absorption spectroscopy and nuclear resonant vibration spectroscopy are presented. We illustrate the perceived reality in fertilizer usage on the field, and fertilizer production in the factory complex with photos and thus provide a contrast to the academic view of the molecular process of ammonia function and production.

Ammonia (NH3) volatilization from NH3-based fertilizer and animal manure reduces their nitrogen (N) fertilizer value and is a source of environmental pollution. Mixing manure with biochar may lower NH3 volatilization from manure by adding H+, adsorbing mineral N, or increasing N immobilization in microbial biomass. The objective of this study was to determine whether wood-based biochar could lower NH3 volatilization from vented pails containing manure (liquid swine, dairy slurry, and solid poultry manure) or a urea ammonium nitrate solution (UAN). Two types of wood-based biochar (BlueLeaf and Dynamotive) were mixed with three types of manure and UAN fertilizer solution at 0, 2.5, 5, 10, and 25% biochar by volume in vented pails. After 21 d storage in an outdoor shaded area, the greatest NH3 volatilization was from poultry manure, which had pH 9.4 on average and low water content regardless of the biochar source and application rate. There was less NH3 volatilization from UAN fertilizer solution when mixed with 25% (v/v) of Dynamotive biochar compared with NH3 volatilization from UAN fertilizer solution mixed with 0%–10% (%) of Dynamotive biochar, probably because pH decreased from 7.0 to 6.4 after 21 d contact. Mixing wood-based biochar with manure had no impact on NH3 volatilization, suggesting that these biochar sources did not appreciably change the pH and N dynamics in stored manure after 21 d.

Warmer atmospheric temperatures (eT) will increase plant nutrient uptake, and elevated atmospheric CO2 (eCO2) is expected to enhance plant growth, whereas a multicomponent eTeCO2 effect should also be beneficial for agroecosystems. Our goal was to understand if single- (eT, eCO2) or multicomponent (eTeCO2) climate effects, predicted for southern Ontario, Canada, will affect soybean and soil properties differently when soil is amended with manure and biochar (MB) or with manure, nitrogen (N) fertilizer, and biochar (MNB) compared with the addition of manure and N fertilizer (MN). We hypothesized that biochar regulates climate effects and causes soybean and soil properties to be similar to ambient climate conditions than soil without biochar. However, soil amended with biochar functioned independently of single- or multicomponent climate effects. Soybean pod and shoot biomass, shoot height, and shoot:root ratio were greater (p 2 increased (p 4+ and NO3−), and the C/N ratio but increased (p

Liquid hog manure (LHM) and solid cattle manure (SCM) co-applied with biochar could beneficially influence soil nitrogen (N) and phosphorus (P) dynamics. A split-plot design was used at two sites (Brown and Black) in Saskatchewan to assess LHM and SCM (100 kg N·ha−1) applied alone or in combination with biochars (8 Mg carbon·ha−1) produced using slow or fast pyrolysis. Crop growth and nutrient uptake, along with fertilizer 15N recovery, were followed over four years in a cereal–oilseed rotation. Crop growth on the Brown soil was more responsive to the treatments than the Black soil, reflecting lower fertility of the Brown soil. The manure and biochar, applied alone or in combination, had little impact on available soil P. Manure and biochar effects on crop growth and nutrient uptake were attributed to temporal effects on soil N immobilization–mineralization influencing plant-available soil N. A negative impact of the fast pyrolysis biochar on growth and plant uptake was observed and attributable to its greater labile-carbon content, which likely promoted soil N immobilization. Synergism observed between SCM and the slow pyrolysis biochar may reflect enhanced net SCM-N mineralization and increased water-holding capacity. The majority (55%–80%) of plant 15N recovery occurred during the first year, with 86% of fertilizer 15N conserved within the soil–plant system after four years. Greater (40%) plant 15N recovery without biochar addition, coupled with increased (38%) soil 15N recovery with added biochar, suggests biochar-related immobilization and (or) sorption in the biochar-amended soils.

Technologies that can effectively address the environmental issues arisen from the use of agrochemicals and P fertilizers are needed for the development of green agriculture. Here, we report a new core–shell P-laden biochar/ZnO/g-C3N4 composite (Pbi-ZnO-g-C3N4) used both as an efficient photocatalyst for degrading atrazine and a promising slow-release fertilizer for improving the P utilization efficiency. In comparison with P-laden biochar/ZnO (Pbi-ZnO), Pbi-ZnO-g-C3N4 exhibits enhanced photocatalytic activity with the maximum atrazine degradation efficiency of 85.3% after 260 min. Pbi-ZnO-g-C3N4 also shows superior P slow-release performance with the cumulative P release concentration of 216.40 g/L in 260 min. Besides, it is found that the coating of g-C3N4 on the surface of Pbi-ZnO improves the utilization of visible light and separation of photoinduced electron-hole pairs, producing more radicals (•OH and •O2–) under visible light irradiation. The mechanistic study reveals that Z-shaped heterojunction is formed between ZnO and g-C3N4 in Pbi-ZnO-g-C3N4, and biochar serves as an electron-transfer bridge that promotes the separation of electron-hole pairs. Finally, pot experiments reveal that the P utilization efficiency for pepper seedlings fertilized by Pbi-ZnO-g-C3N4 is higher than that by Pbi-ZnO. The application of Pbi-ZnO-g-C3N4 is beneficial for the growth of native soil microorganism.

Ammonia (NH3) plays a central role in the chemistry of inorganic secondary aerosols in the atmosphere. The largest emission sector for NH3 is agriculture, where NH3 is volatilized from livestock wastes and fertilized soils. Although the NH3 volatilization from soils is driven by the soil temperature and moisture, many atmospheric chemistry models prescribe the emission using yearly emission inventories and climatological seasonal variations. Here we evaluate an alternative approach where the NH3 emissions from agriculture are simulated interactively using the process model FANv2 (Flow of Agricultural Nitrogen, version 2) coupled to the Community Atmospheric Model with Chemistry (CAM-chem). We run a set of 6-year global simulations using the NH3 emission from FANv2 and three global emission inventories (EDGAR, CEDS and HTAP) and evaluate the model performance using a global set of multi-component (atmospheric NH3 and NH4+, and NH4+ wet deposition) in situ observations. Over East Asia, Europe and North America, the simulations with different emissions perform similarly when compared with the observed geographical patterns. The seasonal distributions of NH3 emissions differ between the inventories, and the comparison to observations suggests that both FANv2 and the inventories would benefit from more realistic timing of fertilizer applications. The largest differences between the simulations occur over data-scarce regions. In Africa, the emissions simulated by FANv2 are 200 %–300 % higher than in the inventories, and the available in situ observations from western and central Africa, as well as NH3 retrievals from the Infrared Atmospheric Sounding Interferometer (IASI) instrument, are consistent with the higher NH3 emissions as simulated by FANv2. Overall, in simulating ammonia and ammonium concentrations over regions with detailed regional emission inventories, the inventories based on these details (HTAP, CEDS) capture the atmospheric concentrations and their seasonal variability the best. However these inventories cannot capture the impact of meteorological variability on the emissions, nor can these inventories couple the emissions to the biogeochemical cycles and their changes with climate drivers. Finally, we show with sensitivity experiments that the simulated time-averaged nitrate concentration in air is sensitive to the temporal resolution of the NH3 emissions. Over the CASTNET monitoring network covering the US, resolving the NH3 emissions hourly instead monthly reduced the positive model bias from approximately 80 % to 60 % of the observed yearly mean nitrate concentration. This suggests that some of the commonly reported overestimation of aerosol nitrate over the US may be related to unresolved temporal variability in the NH3 emissions.

Tomato (Solanum lycopersicum L.) is a major vegetable crop world-wide and grown in high tunnels in many regions. This study investigates the use of two fertilizer sources, chemical and integrated (composted poultry manure plus urea) fertilizers, and grafting on growth, nitrate-N content, yield, and fruit quality of tomato grown in high tunnels in northwestern Washington. Grafting treatments consisted of ‘Panzer’ tomato grafted on one of three tomato rootstocks ‘Estamino’, Maxifort’, ‘DRO138TX’, or non-grafted (control). Application of chemical fertilizer increased number of leaves per plant, plant height, and cumulative fresh biomass of pruned suckers relative to tomato plants grown with the integrated fertilizer treatment. Grafted tomato plants had greater plant growth than non-grafted plants throughout the growing season. There was no significant difference between fertilizer treatments on nitrate-N concentration in plant tissue or fresh petiole sap; however, grafted plants contained higher levels of nitrate-N than non-grafted plants. Total and marketable fruit weight and number did not differ due to fertilizer source, but total and marketable fruit weight was higher for grafted plants than for non-grafted plants in 2016. There was no significant effect due to fertilizer source on fruit firmness, water content, pH, titratable acidity, and β-carotene; however, total soluble solids (TSS) and lycopene content were higher for fruit grown with integrated fertilizer in 2016. Grafting enhanced water content of tomato fruit in 2015, and TSS (°Brix) in 2016.

Sustainable agriculture is an integrated system based on ecological principles, providing society's present food needs, without compromising the ability for current or future generations to meet their needs. In this system, organic and biological fertilizers and bio-pesticides are used to maintain nutrients in the soil, control weeds and pests, and increase biodiversity. The present study aimed to evaluate some traits of Solanum tuberosum following the application of chemical, organic, and biological fertilizers. This study was conducted as a factorial experiment based on randomized complete block design in three replications in two agricultural years of 2017 and 2018. The first factor was chemical/organic fertilizers at five levels (No fertilizer, 100% Urea, 66% urea + 33% Manure, 33% urea + 66% Manure and 100% Manure) and the second factor was tuber inoculation with biological fertilizers at four levels (No bacteria, Azospirillum, Pseuidomonas, Azospirillum + Pseudomonas). The results showed that the combined application of Pseudomonas with 66% urea + 33% manure resulted in the highest protein (1861.6 kg/ha) and biological (140.69 t/ha) yields in the first year. While in the second year the highest biological yield (108.65 t/ha) was achieved by the application of Pseudomonas with 100% urea. The highest tuber protein content (7.05%) and nitrate content (93.45 mg/kg) were obtained by the application of Azospirillum + Pseudomonas with 100% manure in the second year. Although the positive effect of biological fertilizers, especially Pseudomonas, has been shown on potato characters, the use of biological fertilizers alone cannot completely replace the chemical fertilizers. Therefore, sustainable agriculture can be achieved by the implementation of integrated plant nutrition using urea, manure, and biofertilizers.

Phosphorous (P) plays the prominent role to promote the plants storage functions and structural roles, as it is recognized as a vital component of ADP, ATP, Cell wall as well as a part of DNA. Soils acts as the sink to supply P to plants because soil pH and its physical condition are the main factor which regulate the solubility and availability P element. Phosphorus is not deficient in Pakistani soils but its availability to plants is the serious matter of concern. A pot experiment was conducted to evaluate P dynamics in two different soil series of Pakistan (Bahawalpur and Lyallpur) using Maize as test crop. The treatments applied were T0: Control (without any fertilizer), T1: Recommended DAP @648 mg pot−1, T2: Half dose DAP @324 mg pot−1, T3: Recommended rate of TSP @900 mg pot−1, T4: Half dose TSP @450 mg pot−1. Soil analysis showed that Bahawalpur soil has sandy clay loam texture with 33% clay and Lyallpur series has sandy loam texture with 15.5% clay; furthermore, these soil contain 4.6 and 2.12% CaCO3 respectively. Results showed an increase in P concentration in roots (23 mg kg−1) with the application of half dose of TSP in Lyallpur series and lowest in Bahawalpur series (14.6 mg kg−1) at recommended dose of DAP. Concentration of P in shoots responded the same; increase at half dose of TSP (16.7 mg kg−1) and lowest at full dose of DAP in Bahawalpur series as (15.58 mg kg−1). Adsorbed P (17 mg kg−1) was recorded highest in Bahawalpur soil with more clay amount in pot with DAP application but lower in Lyallpur soil series (14 mg kg−1) with the application of applied TSP. The PUE was recorded highest in Lyallpur series with the application of half dose of TSP and it was 61% more than control and was Highest in Bahawalpur series was with the application of recommended dose of DAP is 72% more than control treatment. On estimation; results showed that applied sources made an increase in P availability than control, but TSP gave better P uptake than DAP unless of rates applied. Soil of Lyallpur series showed better uptake of P and response to applied fertilizers than Bahawalpur series which showed more adsorption of P by high clay and CaCO3 amount. Conclusively, the study suggested that soil series play a crucial role in choosing fertilizer source for field application.

A growing demand for food products from limited arable land has meant that paddy fields have been developed to provide both grain and aquatic products. China has the world's largest aquaculture area of crayfish, of which ∼86% is in the form of rice-crayfish coculture. Here, we use a life cycle assessment to evaluate and compare the environmental impacts of three farming systems: rice monoculture, crayfish monoculture, and rice-crayfish coculture. Two functional units were used: one hectare of land occupied, and one Nutrient Density Unit (NDU) – i.e., the combined nutrition delivered in rice and/or crayfish products. Rice-crayfish coculture has a larger environmental footprint than rice monoculture per hectare occupied across at least 7 of the 8 impact categories studied, though performs better than crayfish monoculture. However, rice-crayfish coculture yields 1.12 to 2.21 times more nutrition per hectare than rice monoculture and crayfish monoculture, respectively. Hence, rice-crayfish coculture was found to have lower impact per NDU across all 8 impact categories studied, compared with the monoculture systems. Application of urea, crayfish feed inputs, and electricity consumption dominated most environmental burdens for rice-crayfish coculture, while field emissions (e.g., CH4 and NH3) strongly influenced global warming potential, terrestrial acidification potential and freshwater eutrophication potential, respectively. Environmental burdens of rice-crayfish coculture could be further reduced by increasing productivity per hectare and/or improving fertilizer and feed use efficiency. Shifting from rice- and crayfish-monoculture to rice-crayfish coculture could deliver more nutrition at a lower environmental cost, as well as increasing farm profitability by 7−462%.

To evaluate whether small farmers are willing to accept the policy of sustainable use of cultivated land such as green manure planting, we analyze the payment preference and the source of heterogeneity of small farmer’s environmental attributes of leguminous green manure. A choice experiment method is conducted to learn about small farmer’s preference toward green manure. The results suggest that small farmers with planting confidence are willing to pay for different environmental attributes of leguminous green manure. Among them, the willingness to pay (WTP) for the quality and fertility of cultivated land is the highest, and the WTP for air quality is the lowest. Small farmers who do not have confidence in planting are only willing to pay for attribute of natural disaster days. We identify key factors that might influence small farmer’s payment preference, including gender, age, education level, degree of part-time employment, and the trend perception of environmental change.

Novel processes for the sustainable production of fertilizers are highly sought after to combat climate change. Herein, we demonstrate that by irradiating with strong UVA-light, TiO2 is able to photocatalytically oxidize molecular nitrogen in the gas phase under ambient conditions to NOx and nitrate. The reaction produces predominantly nitrogen dioxide with a high selectivity of up to 93% which could be captured afterwards to produce nitric acid or nitrates and used as sustainable (solar) fertilizer.

Ammonium phosphate fertilizer is the compounds containing nitrogen and phosphorus that are usually produced through the neutralization reaction of phosphoric acid and ammonia. At present, there are a variety of products, such as slurry monoammonium phosphate (MAP), diammonium phosphate (DAP), industrial grade MAP, water soluble MAP, water soluble ammonium polyphosphate (APP) and so on. After more than 60 years of development, China’s ammonium phosphate fertilizer industry has experienced the road of from scratch and from weak to strong. The successful development of the slurry MAP technology ended the history that the high concentration phosphate fertilizer cannot be produced by using the medium and low-grade phosphate ore. The continuous, stable and large-scale production of DAP plant provides sufficient guarantee for diammonium products in China. The development of new ammonium phosphate fertilizer products, such as industrial grade MAP, water soluble MAP, water soluble APP, provides technical support for the transformation and upgrading of phosphorus chemical enterprises. In this paper, the production methods, the development history and the latest research progress of ammonium phosphate fertilizers were reviewed.

ADC12 aluminium dross and 6063 aluminium dross are the byproducts of aluminium production process. The processing of these dross is of great challenges due to its toxic nature. In the current study, neutralized dross was used as plant fertilizer. The planting efficiency of untreated and treated aluminium dross fertilizer at various contents up to 50 wt% was analyzed. Treated aluminium dross fertilizer showed enhancement in height and weight of Chinese cabbage than untreated fertilizer and control. The optimum content for plant growth enhancement was found to be 10 wt%. However, the plants treated with 30 wt% and 50 wt% of aluminium dross fertilizer were completely withered and desiccated after 10 days of growth. The growth enhancement was also observed in sweet corn, basil and spring onion. Hence, the aluminium dross after neutralization can be used as an environmentally friendly fertilizer as there is no existence of toxic heavy metal elements in the soil.

Effect of chemical- and bio-fertilizers (Nitroxin) on growth parameters, physiological and biochemical attributes, and yield of cantaloupe (Cucumis melo L.) under water stress conditions has been studied. Irrigation was done at 3 levels including 50, 75, and 100% of the water requirement of the cantaloupe plant. Water stress had an adverse effect on plant growth and the application of 120 kg ha−1 chemical fertilizer with Nitroxin in 100% water requirement had the highest growth parameters including fruit weight (1.84 kg) and fruit length (20.71 cm). The highest Malondialdehyde content was observed at 60 kg ha−1 of chemical fertilizer using Nitroxin. Application of Nitroxin had a significant effect on electrolyte leakage, proline content, relative water content, colour, vitamin C, titratable acidity, firmness, and total soluble solids (TSS) during water stress. The highest content of total chlorophyll (5.81 mg g−1 fresh weight) was observed at 100% field capacity with 180 kg ha−1 of chemical fertilizer with Nitroxin. The total phenol content of fruit enhanced by increasing drought stress and a significant difference was observed by application of biological and chemical fertilizers compared to control. Antioxidant enzyme activity including ascorbate peroxidase, catalase, superoxide dismutase and peroxidase increased during water stress and the application of chemical fertilizer with Nitroxin enhanced antioxidant enzyme activity during stress. Overall, the application of chemical fertilizers and Nitroxin improved growth parameters, physiological and biochemical attributes and yield of cantaloupe plants during water stress.

This study was carried out to examine the production of liquid fertilizer made from goat feces (LFGF) as well as the potency of LFGF for increasing plant growth and yield of vegetables. The study was conducted through 3 studies. The first study was begun with compiling a formulation for LFGF. The selected-raw-material was goat feces added with sugar and ZA, as well as EM (Lactobacillus sp., Actinomycetes sp., Streptomyces sp. and Yeast). The experimental results indicated that an increase in the concentration of ZA resulted in an increase in the total N and S content, as well as an increase EC of LFGF. Increased sugar concentration results in a decrease in pH and an increase in lactic acid content, whereas an increase in ZA decreases the formation of acetic acid. The use of sugar 25 g L−1 water and ZA 50 g L−1 water could produce the best quality of LFGF. The second study was to examine the selected LFGF combined with AB-Mix nutrient solution on the growth and yield of three types of leaf vegetables which were cultivated hydroponically. The results indicated that LFGF can potentially replace AB-Mix fertilizer by up to 50% in hydroponic vegetable cultivation. The third study was to examine the selected LFGF as nutrients availability of mustard that was cultivated in pots, given through planting media with a concentration of 1:40 L−1 water (EC 2300 μS cm−1). It shows that LFGF has the potential to increase the growth and yield of mustard plants in pots.

Zinc is an essential micronutrient that is required for optimum plant growth. It is present in soil in insoluble forms. Bacterial solubilization of soil unavailable form of Zn into available form, is an emerging approach to alleviate the Zn deficiency for plants and human beings. Zinc solubilizing bacteria (ZSB) could be a substitute for chemical Zn fertilizer. The present study aimed to isolate and characterize bacterial species from the contaminated soil and evaluate their Zn solubilizing potential. Zn resistant bacteria were isolated and evaluated for their MIC against Zn. Among the 13 isolated bacterial strains ZSB13 showed maximum MIC value upto 30mM/L. The bacterial strain with the highest resistance against Zn was selected for further analysis. Molecular characterization of ZSB13 was performed by 16S rRNA gene amplification which confirmed it as Pseudomonas oleovorans. Zn solubilization was determined through plate assay and broth medium. Four insoluble salts (zinc oxide (ZnO), zinc carbonate (ZnCO3), zinc sulphite (ZnS) and zinc phosphate (Zn3(PO4)2) were used for solubilization assay. Our results shows 11 mm clear halo zone on agar plates amended with ZnO. Likewise, ZSB13 showed significant release of Zn in broth amended with ZnCO3 (17 and 16.8 ppm) and ZnO (18.2 ppm). Furthermore, Zn resistance genes czcD was also enriched in ZSB13. In our study, bacterial strain comprising Zn solubilization potential has been isolated that could be further used for the growth enhancement of crops.

The study was aimed to evaluate the effect of successive applications of increasing biochar rates along with other mineral fertilizers and poultry manure on onion nutrition and yield. The experiment consisted of 2 (agricultural year) × 11 (treatments) factorial combinations over two cropping years (2017 and 2018). Thus, 11 treatments were tested as follows: C = control; MF = mineral fertilizer; PM = poultry manure; B1+ MF = 1 Mg ha−1 of biochar+MF; B1+ PM = 1 Mg ha−1 of biochar+PM; B2+ MF = 2 Mg ha−1 of biochar+MF; B2+ PM = 2 Mg ha−1 of biochar+PM; B4+ MF = 4 Mg ha−1 of biochar+MF; B4+ PM = 4 Mg ha−1 of biochar+PM; B10+ MF = 10 Mg ha−1 of biochar+MF; B10+ PM = 10 Mg ha−1 of biochar+PM. The highest onion yield (39.9 Mg ha−1) was obtained in 2017 with the biochar rate of 5.9 Mg ha−1 while an increase of 308 kg ha−1 in onion yield was found for each Mg ha−1 of biochar added to soil in 2018. The use of biochar combined with mineral fertilizers increased onion yield; and the use of biochar combined with poultry manure improved soil fertility status.

Ketak ( Lygodium circinnatum (Burm.F) Sw.) is one of the main species of non-timber forest products (NTFP s ) in West Nusa Tenggara. Ketak produce tendrils that was used as a raw material for the woven handicraft industry. The sustainability of the handicraft business has constraints in decreasing the supply of raw materials because the potential is very reduced in nature so that it is necessary to make efforts to cultivate L. circinnatum plants. The aim of the study was to determine the success of planting L. circinnatum with fertilization and different types of vines . The research used a randomized block design which was arranged factorially with a combination of different types of fertilizers (goat manure, cow manure, NPK fertilizer ) and vine tree s ( Gliricidia sepium , Erythrina variegata , bamboo). For six months, the application of fertilizers and different types of climbing stems significantly affected the increase in tendril length and number of leaves and there was an interaction between the two treatments tested; while the increase in the number of tendrils and life percentage occurred the effect of a single treatment. Goat fertilizer and climbing species G. sepium were the best treatments for the increase in tendril length (73.4 cm) and number of leaves (88 sheet). The best NPK fertilizer treatment for the growth of the number of tendrils (3 tendrils), climbing species G. sepium and goat manure produced the highest percentage of life (80.42% and 85.56%)

Screw tree is a shrub from family Malvaceae that has many benefits in pharmacy. Screw tree seed has very hard seed coat, so the seed must be treated before germination. The aim of this research was to assess the characteristic of fruit and seeds, effect of seed breaking dormancy, and effect of NPK fertilizer dosage on the growth of screw tree (Helicteres isora) seedlings. The results indicated that screw tree fruits belong to dry fruits with capsule form and has 5 follicles that has different direction. Screw tree seed is orthodox type that has 9 ̶ 36 seeds in one follicle with triangle and square shape. Germination technique in laboratory with soaking the seeds in hot water 100oC until the water cool for 48 hours treatment produced the best germination amounting to 65.0%. Germination technique in green house with soaking the seeds in hot water 100oC until the water cool for 24 hours treatment was the best germination amounting to 77.0%. Seedlings fertilized with 1 g NPK doses increased screw tree growth in diameter parameter of 6.35 mm and shoot-root ratio parameter of 3.9 compared to control.

Introduction while more than 2 million tones of nitrogen fertilizers is annually used in Iran (FAO, 2011: Motasharrezadah et al., 2015), it is documented that just only 20 percent of applied nitrogen fertilizers is uptaken in some wheat farms of Iran (Karimizarchi, 2015). In other words, around 80 percent of nitrogen fertilizers are lost through leaching and volatilization, which increases the potential of environmental contamination with increase N input expenditure of the farmer, or stored in the soil. So the present study was aimed to quantify the role of ammonia volatilization from Iranian soils and to introduce simple as well as helpful techniques for ammonia volatilization reduction in Iranian wheat farms. Materials and methods Firstly, a modified closed dynamic air flow system was provided. Soil materials were provided from tea research institute located in Lahijan, Iran as well as National Salinity Research station located in Ashkezar province, Yazd, Iran. The soils with three levels of acidity (7.88, 6.5 and 7.88) were incubated with 5 sources of nitrogenous fertilizers including ammonium sulphate, ammonium nitrate, urea, sulphur coated urea and potassium nitrate for 22days. Daily and cumulative volatilized ammonium was collected in 20 ml of 2% boric acid indicator solution and it was titrated with 0.01 N HCl. The analysis of variance for different parameters was done following ANOVA technique. When F was significant at p ≤ 0.05 level, treatment means were separated using DMRT. Results and discussion the results showed that soil acidity, fertilizer source and their interactions had significant effect on total volatilized nitrogen, maximum volatilized rate and day of highest volatilization rate. Total volatilized nitrogen depends on nitrogen fertilizer source and soil acidity. The results showed that more than 59 percent of applied ammonium sulphat at soil with the pH value of 7.88 lost through ammonia volatilization and resulted in air pollution. The volatalized nitrogen for sulphur coated urea and potassium nitrate equalled to 7.6 and 0.018 percent while that of ammonium nitrate and urea equalled to 49 percent. The results showed that potassium nitrate had the minimum cumulative ammonium volatilization of less than 0.07 mg N and it was not affected by soil acidity. In addition, our results proved that soil pH reduction from 7.88 to 6.5, reduced total ammonia volatilization for ammonium sulphate and nitrate from 227.15 and 189.82 to 2.39 and 0.99 mg N, respectively. Total volatilized nitrogen from ammonium sulphate and nitrate from soil with the pH of 4.5 were 2.51 and 1.33 mg N, respectively. While soil pH reduction from7.88 to 4.5 from soils treated with urea reduced ammonia volatilization from 188 to 157, this increased ammonia volatilization from sulphur coated urea from 29.2 to 87.05 mg N. In other words, our results proved that increasing soil pH resulted in significant decrease in total volatilized ammonia from sulphur coated urea. The total volatilized nitrogen from soils with the pH values of 4.5, 6.55 and 7.88 was equal to 22, 20 and 6 percent of applied sulphur coated urea. Maximum volatilized rate of ammonium was affected by soil pH and fertilizer sources. With decreasing soil pH the maximum volatilization rate from urea fertilizer was increase. The similar trend was found for sulphur coated urea. However, the maximum volatilization rate from ammonium nitrate and sulphate increased with soil pH increase. Interestingly, soil pH had not significant effect on maximum volatilized rate from potassium nitrate fertilizer and it was equal to 0.04 mg N per day. Conclusion As ammonia volatilization depends on nitrogen source, it is possible to decrease ammonia loss by selecting proper nitrogen fertilizer source. The results demonstrated that potassium nitrate had minimum ammonia loss and can be introduced as the optimum source of nitrogen fertilizer for a wide range of soil pH from 4.5 to 7.88. Ammonium nitrate and ammonium sulphate fertilizers had the least ammonia loss at soils with pH of 6.55 and less. However, sulphur coated urea had the least ammonia loss at soil pH of 7.88 and more.

BACKGROUND Foliar application of highly concentrated ZnSO4 fertilizer improves Zn biofortification in wheat grains. However, excess ZnSO4 ·7H2 O concentration (≥ 5 g kg-1 , w v-1 ) has been associated with leaf burn and yield loss, necessitating the need for Zn sources with high threshold concentration. Therefore, the aim of this study, based on a 2-year field experiment conducted on wheat cultivated in acidic and alkaline soil, was to identify a suitable Zn formulation with a high Zn concentration or efficient adjuvant to achieve optimal Zn biofortification levels without compromising agronomic performance. RESULTS There was a continued increase in the Zn concentration of wheat grains and a decrease in grain yield with an increase in the concentration of the Zn foliar sprays in both soil types examined. Wheats treated with chelated Zn foliar sprays (ZnGly and ZnEDTA) had less foliar injury compared with those treated with unchelated Zn fertilizers. Furthermore, respective of wheat cultivars and soil types, ZnEDTA applied to wheat at a concentration of 10 g kg-1 achieved the highest grain Zn concentration without negatively affecting the wheat performance. Adjuvant type and concentration caused no significant variation in grain Zn concentration. CONCLUSION Overall, without foliar burn, wheat treated with 10 g kg-1 ZnEDTA foliar spray had the best performance with regards to grain Zn concentration and grain yield, which could have considerable implications for Zn biofortification of wheat grain. This article is protected by copyright. All rights reserved.

Selenium (Se) plays an important role in human health. Approximately 80% of the world’s population does not consume enough Se which recommended by WHO (World Health Organization). Wheat is an important staple food and Se source for most people in the world. This article summarizes literatures about Se from 1936 to 2020 to investigate Se in wheat farming soil, wheat, and its derived foods. Se fortification and the recommended Se level in wheat were also discussed. Results showed that Se contents in wheat farming soil, grain, and its derived foods around the world were 3.8–552 (mean, 220.99), 0–8,270 (mean, 347.30), and 15–2,372 (mean, 211.86) μg·kg−1, respectively. Adopting suitable agronomic measures could effectively realize Se fortification in wheat. The contents in grain, flour, and its derived foods could be improved from 93.94 to 1,181.92, 73.06 to 1,007.75, and 86.90 to 587.61 μg·kg−1 in average after leaf Se fertilizer application in the field. There was a significant positive correlation between Se content in farming soil and grain, and it was extremely the same between foliar Se fertilizer concentration rate and grain Se increased rate. The recommended Se fortification level in cultivation of wheat in China, India, and Spain was 18.53–23.96, 2.65–3.37, and 3.93–9.88 g·hm−2 respectively. Milling processing and food type could greatly affect Se content of wheat derived food and should be considered seriously to meet people’s Se requirement by wheat.TOC graphic

BACKGROUND Rapeseed (Brassica napus) is highly sensitive to nitrogen (N) and boron (B) deficiency; however, the synergistic effects of these elements on rapeseed production are poorly understood. The aim of this study was to investigate the effects of co-application of N and B on seed yield, N uptake and N use efficiency (NUE) of rapeseed. Three rapeseed cultivars (W10, ZS11 and HG) were treated with different N and B application rates, and the seed yield, N uptake and NUE were examined in two-year field experiments. RESULTS The application of B fertilizer (4.5, 9 kg borax ha-1 ) improved N uptake, NUE and seed yield. However, the magnitude of increase in seed yield by B fertilization was dependent upon the rate of N supply and genotype. The benefit of B was much greater at 180 kg N ha-1 than at 0, 60 kg N ha-1 . The combination of N and B also improved N remobilization from sources (stems and husks) to sinks (seeds) and increased N recovery efficiency (NRE). Compared with the B-inefficient cultivar W10, the B-efficient cultivars ZS11 and HG were superior in growth, seed yield, N uptake and NUE on B deficient soils. Furthermore, B-efficient cultivars showed great potential in saving N input, and the yield increased by more than 40% under B deficiency conditions. CONCLUSION This study highlights a markedly synergistic effect of N and B nutrition on rapeseed NUE and yield production and shows that B-efficient genotypes can increase yield and reduce N inputs under B-deficient conditions. This article is protected by copyright. All rights reserved.

El café es un cultivo de importancia social y comercial, se estima que es el sustento de 25 millones de familias en las regiones tropicales y subtropicales del mundo. Con el objetivo de evaluar el crecimiento, desarrollo y concentración de macronutrientes en genotipos de café con diferentes dosis de abono orgánico se realizó un ensayo en el centro experimental Sacha Wiwa, bajo un diseño de bloques aleatorios con arreglo factorial (genotipos x dosis de abono orgánico Bioabor®). Las variables que se midieron fueron altura de planta, diámetro del tallo, concentración y relación de macronutrientes en el tejido foliar, análisis físico y químico del suelo al inicio y final del estudio. Los datos fueron analizados con estadística descriptiva univariante y técnicas paramétricas. Para la comparación entre medias se empleó el test Tukey al 95% de probabilidad. La variedad Ecorobusta fue la que obtuvo la mayor altura y diámetro de tallo. El abono orgánico inhibe el crecimiento y desarrollo del cultivo de café. Las dosis de abono a 1000, 1500 y 2000 kg /ha aplicada en este orden en la variedad NapoPayomino, Ecorobusta y Conilón reducen la concentración de N en el tejido foliar. Se encontró una correlación positiva significativa entre la altura de planta y diámetro del tallo.

A controlled fermentation was conducted to develop and design a bioorganic fertilizer based on three wastes generated by the food industry: olive mill wastewater (OMW), molasses and rice hulls by inoculation with selected strains of lactic acid bacteria (LAB), of the species “Lactiplantibacillus plantarum” and “Levilactobacillus brevis” and of the yeast of the species “candida famata”. The fermentation with commercial yeasts and particularly the species of “saccharomyces” produced an unstable fertilizer with a high pH value (6.14).Whereas, the fermentation test with an inoculum composed of 20% yeast and 80% lactic acid bacteria showed a decrease in pH at 4.66 and a maximum enzymatic activity of 43.900 IU/l after 30 h. This combination allowed an appropriate morphological and microbiological quality of the bioorganic fertilizer. To determine with precision, the optimum conditions of this fermentation an optimization design was applied. As a result of experiments and statistical validation of the fitted model, the bioorganic fertilizer with the lowest pH value was achieved after fermentation of 53.2% OMW, 19.1% molasses, 21.3% rice hulls and 6.4% inoculum content. The final pH was able to reach a value of 4.07 with desirability of the order of 99.7%. A fertilizer with the lowest possible pH allowed farmers longer storage periods and required no special storage conditions.

Under small and marginal farm conditions, allocation of land exclusively for forages is not possible. Hence, integration of forages in existing crop geometry can ensure production of grain and fodder, simultaneously under rainfed conditions. A field experiment was conducted to study the effect of different nutrient management practices on rice and fodder intercropping systems under rainfed conditions during 2015–2017. The intercropping system comprised (i) sole rice (R), (ii) rice and cowpea (5:2) (CP) and (iii) rice and ricebean (5:2) (RB) whereas the different nutrient management practices comprised (i) application of farm yard manure (FYM) at 5 t ha–1 (farmers’ practice) (N1), (ii) application of inorganic fertilizer (recommended dose of fertilizer (RDF) of rice, 60:30:30 kg ha–1 of N:P2O5:K2O) (N2) and (iii) application of both FYM at 5 t ha–1 and 50% of RDF inorganic fertilizer (N3). The results of the experiment revealed that the growth attribute such as leaf area was influenced significantly when fodder crops were taken as intercrops because rice plant was getting more nitrogen from soil due to nitrogen fixation of leguminous fodder crops. Among the nutrient management practices, significant differences in leaf area were found beween N2 and N1, and between N3 and N1 treatments. However, regarding total number of effective tillers, significant differences were found neither between nutrient management practices nor between cropping systems. The rice equivalent yield (REY) based on price (REYP) was found to be significantly lower in CP (2 615 kg ha–1; –6.4%) and RB intercropping systems (2 571 kg ha–1; –8.0%) than in R monocropping system (2 794 kg ha–1). However, the REY based on energy (REYE) of CP (2 999 kg ha–1; +7.3%) and RB (2 960 kg ha–1; +5.9%) were found to be significantly higher than that of R (2 794 kg ha–1) irrespective of nutrient management practices. Between different nutrient management practices, the N3 treatment recorded the highest REYP and REYE which was at par with the N2 treatment and significantly higher than the N1 treatment irrespective of cropping systems. The combined application of both organic and inorganic sources of nutrients helped to supply nutrients throughout the growing season, which led to improved growth parameters and rice yield. The R monocropping system resulted in more income and rain water use efficiency (RWUE) closely followed by rice and fodder intercropping systems. However, the REYE and energy use efficiency (EUE) of rice and fodder intercropping systems were higher than those of R. Also, fodder helped to meet the requirement of cattle feeding in the off-season. Hence, the intercropping system is advocated in the study zone. Further study can be done on ecosystem services and carbon sequestration potential of the intercropping system, as well as the system’s coping ability in response to short drought through observing periodic soil moisture regime in root zone.

Crested wheatgrass (CWG) [Agropyron cristatum (L.) Gaertn.] is a commonly introduced grass in the Canadian prairies, but concerns remain about its possible long-term effects on soil quality, and its influence on soil water repellency (SWR) has not been determined. The long-term (24 yr) effects of CWG on SWR in comparison to seeded native grasses and annual cropping were determined for a clay loam soil in southern Alberta, Canada by measuring SOC concentration and SWR using soil hydrophobicity (SH) and soil water repellency index (RI) methods. The cropping treatments were CWG, seeded native grass mix (NGM), continuous wheat, and wheat–fallow rotation, each with fertilized (nitrogen) and non-fertilized subplots, replicated four times. Mean SOC concentration, SH, and RI in samples of surface soil were similar (P > 0.05) for CWG and seeded NGM, and they did not support our hypothesis (seeded NGM > CWG). Mean SOC was significantly greater for seeded perennial grasses than annual crops by 1.7–2 times and SH by 2.1–2.5 times, which supported our hypothesis, but RI was similar among treatments. As expected, nitrogen fertilization significantly increased SOC concentrations, but the effects on SH and RI were undetectable. A strong positive correlation occurred between SOC concentration and SH (r = 0.92) but not for RI (r = 0.10). Our findings suggested that SWR was similar for CWG and seeded NGM. The SWR as measured using SH was greater for seeded perennial grasses than annual cropping but was similar using RI.

Horticultural systems, specifically vegetable production systems, are considered intensive agricultural systems as they are characterized by high nitrogen (N) fertilizer application rate, frequent tillage, and irrigation operations. Accordingly, horticultural production in temperate climates is prone to N losses — mainly during post-harvest (during fall and winter) or pre-plant (spring) periods — such as N2O emissions and nitrate leaching. The risk for N losses is linked to low crop N use efficiency (NUE) combined with a narrow C:N and high N content of crop residues. Here we reviewed the studies conducted in Canada and similar climates to better understand the risk of N2O emission and potential agronomic management strategies to reduce N2O emissions from horticultural systems. Current knowledge on N2O emissions from horticultural systems indicate that increasing crop NUE, modifying the amount, type, time, and rate of N fertilizer inputs, and adopting cover crops in crop rotations are some of the effective approaches to decrease N2O emissions. However, there is uncertainty related to the efficiency of the existing N2O mitigation strategies due to the complex interactions between the factors (soil characteristics, type of plant species, climatic conditions, and soil microbial activity) responsible for N2O production from soil. Little research on N2O emissions from Canadian horticultural systems limits our ability to understand and manage the soil N2O production processes to mitigate the risk of N2O emissions. Thus, continuing to expand this line of research will help to advance the sustainability of Canadian horticultural cropping systems.

Deep placement of nitrogen fertilizer is a key strategy for improving nitrogen use efficiency. A two-year field experiment was conducted during the early rice growing seasons (March–July) of 2016 and 2017. The experimental treatments comprised two rice cultivars: Wufengyou 615 (WFY 615) and Yuxiangyouzhan (YXYZ), and three N treatments: mechanical deep placement of all fertilizers as basal dose at 10 cm soil depth (one-time deep-placement fertilization, namely OTDP fertilization); manual surface broadcast (the common farmer practice) of 40% N fertilizer at one day before sowing (basal fertilizer) followed by broadcast application of 30% each at tillering and panicle initiation stages; and no fertilizer application at any growth stage as a control. One-time deep-placement fertilization increased grain yield of both rice cultivars by 11.8%–19.6%, total nitrogen accumulation by 10.3%–13.1%, nitrogen grain production efficiency by 29.7%–31.5%, nitrogen harvest index by 27.8%–30.0%, nitrogen agronomic efficiency by 71.3%–77.2%, and nitrogen recovery efficiency by 42.4%–56.7% for both rice cultivars, compared with the multiple-broadcast treatment. One-time deep-placement fertilization reduced CH4-induced global warming potential (GWP) by 20.7%–25.3%, N2O-induced GWP by 7.2%–12.3%, and total GWP by 14.7%–22.9% for both rice cultivars relative to the multiple-broadcast treatment. The activities of glutamine synthetase and nitrate reductase were increased at both panicle-initiation and heading stages in both rice cultivars following one-time deep-placement fertilization treatment. Larger leaf area index at heading stage and more favorable root morphological traits expressed as larger total root length, mean root diameter, and total root volume per hill were also observed. One-time deep-placement fertilization could be an effective strategy for increasing grain yield and nitrogen use efficiency and lowering greenhouse-gas emissions under mechanical direct-seeded cropping systems.

Only 47% nitrogen of fertilizer is taken up by a plant whereas more than 40% nitrogen of total applied fertilizer is lost to environment that causes several environmental as well as economic consequences. Slow-release fertilizers are considered as a possible large-scale solution for nitrogen loss. The present study aims to stabilize urea by coating with four different materials including calcium phosphate (CP), gypsum powder (GP), calcium nitrate (CN), and gelatin (G) individually and in combination for slow release of nitrogen to sorghum crop. The physical and chemical characteristics of coated urea were examined by FT-IR, powder XRD, SEM, and rushing strength. Results showed that coating of CP, GP, and CN over urea was uneven and rough while G coating was smooth and admirable, and no pore was observed on the surface and indicated a weak water-urea interaction. Similarly, CPG coating over urea showed a maximum crushing strength of 2.38 N/m2. Slow-release and soil leaching analysis revealed that G coated urea showed the maximum 39.12 and 779.36 ppm nutrient loss after 15- and 480-min treatment, respectively which is much better than uncoated urea (99.81 and 993.65 ppm). Results reported that the maximum plant height, diameter, and chlorophyll were observed as 132.91 ± 1.52 cm, 24.56 ± 1.00 mm, and 56.30 ± 1.03 mg/m2 with CNG coated urea. Similarly, CNG also revealed the maximum dry matter yield (DMY) of 25226.15 kg/ha in shoots and 2633.50 kg/ha in roots, nitrogen uptake (NU) of 18153.75 kg/ha in shoots and 233.99 kg/ha in roots, and apparent nitrogen recovery (ANR) of 71.14% in shoots and 4.55% in roots. It is concluded that CNG coated urea showed better DMY, NU, ANR, and pot analysis, and it is recommended as a slow-release fertilizer for large scale application to minimize nutrient loss and maximize crop production.

Insect production provides an opportunity to solve problems in our food system. Producers are focused on redirecting waste streams to strive for a zero waste system. By-products and left-over substrates generated include: frass, chitin, and lipids. Frass can be beneficial as a plant fertilizer. It is also known to exhibit anti-microbial and anti-pathogenic properties that may be utilized as a potential insecticide. Chitin has similar fertilizer and anti-pathogen properties. Chitin also produces anti-inflammatory and antimicrobial properties, potentially improving immune responses in animals. Fatty acids found in lipids may serve as environmentally friendly biodiesel. Additionally, the oleic acids found in lipids have known health benefits for humans and other animals. As insect systems expand, zero waste goals will increase in importance.

There is a huge potential for recycling animal manure in agricultural farms, but fecal microorganisms from land-applied animal manure can join shallow groundwater through leaching especially in alluvial formations. Thus, this study investigated the leaching rate of total viable count (TVC) below a 1.1-m soil depth in a field lysimeter planted with rice–maize–rice rotation, where the rotation received different treatments, i.e., chemical fertilizer, dry manure, fresh manure, alternate wetting and drying (AWD) irrigation, and traditional irrigation. Leachate samples of six major irrigation/rainfall events were collected and analyzed for TVC concentration. In the Aman rice season, manure application had a significantly higher TVC leaching (5.5 × 106 colony forming units (CFU) per milliliter) than the no-manure treatment (8.2 × 104 CFU/mL). In the maize season, manure application increased more than one log-scale of TVC leaching concentration. A higher concentration of TVC leaching (3 × 105 CFU/mL) was observed even after 93 d of fresh manure application. The fresh manure had a higher TVC load, and it possibly helped microorganisms survive longer by providing a more manure-like environment in the soil. In the Boro rice season, manure application increased the TVC leaching up to 3–4 log-scale compared with the control treatment. The AWD irrigation increased TVC leaching compared with the continuous irrigation because the desiccation fractures developed in the AWD irrigation helped TVC bypass the organic-rich topsoil. The Boro rice fields had higher TVC leaching than the maize fields with higher manure doses. The study suggests that there is scope to improve manure management to protect the groundwater quality.

Cadmium (Cd) has become the primary pollution factor in farmland, which seriously threatens crop growth and food safety. A pot experiment was conducted to investigate the effect of combined application with biochar and P fertilizer on soil Cd availability and translocation, in which biochar was 0 (C0) and 20 g kg-1 (C20), P fertilizer was 0 (P0), 20 (P20), and 40 mg P kg-1 (P40). Results showed that, compared with C0 level, the content of DTPA-Cd in soil was significantly decreased with biochar addition after 60 days of cultivation, under C20 level, soil DTPA-Cd in C20P40 treatment were significantly increased. Under both C levels, the percentage of exchangeable Cd fraction at P40 rate was significantly lower than that at P20 rate, because the excess P in soil could precipitate Cd. The percentage of residual-Cd fraction was significantly increased with the combined addition of biochar and P fertilizer, particularly in C20P40 treatment, which was 75.95%, while it was only 61.65% in C0P0 treatment. The Cd translocation factor (TF) and bioconcentration factor (BCF) were also significantly reduced in C20P20 and C20P40 treatments compared with C0P0 treatment. Therefore, the combined high P and biochar application was a good choice in inhibiting soil Cd availability and plant Cd uptake, which benefited to the safe utility of the Cd contaminated soil.