Search

The effects of organic and inorganic nitrogen fertilizer on the morphology and anatomy of Cannabis sativa “Fédrina” (industrial fibre hemp) was investigated in both a greenhouse and field setting in Northern British Columbia. Plots (90 stems/m2) treated with 0, 75, 150 or 300 kg N/ha of inorganic nitrogen, or fish meal, blood meal or sea star organic fertilizers were also replicated with 90 kg inorganic P2O5/ha application. The application of 150 and/or 300 kg N/ha of any nitrogen fertilizer type benefited field-grown plant morphology, secondary phloem fibre and xylem development, while greenhouse-grown plant morpology, secondary phloem fibre and xylem were positively influenced by 90 kg P2O5/ha. Primary phloem fibre characteristics of both greenhouse and field-grown plants were benefited by the absence of either nitrogen or phosphorus fertilizer. This study determined that the response of C. sativa “Fédrina” fibre production to organic nitrogen application was comparable to that of inorganic nitrogen application. doi:10.1300/J237v11n02_02 [ABSTRACT FROM PUBLISHER]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nitrogen fertilizers have revolutionized agriculture since the early 20th century and made a decisive contribution to combating world hunger. Nevertheless, the technology is controversial today because production is energy-intensive and contributes significantly to climate change. In addition, conventional fertilizers pollute groundwater, rivers and coastal waters. Synthetic nitrogen fertilizer is made from ammonia (NH3) produced by the Haber-Bosch process, for which a patent was filed with the German Imperial Patent Office in 1908 (DE235421). For the urgently needed development of modern climate-friendly fertilizers, patent law seems to have played a minor role so far. The large and patent-active agrochemical corporations in the industrialized countries are focusing on other technologies, leaving fertilizer production to companies with direct access to energy below the global market price. Another reason is the very generous regulation of nitrogen fertilizers. For farmers, the use of less climate-damaging fertilizers is not worthwhile. However, the disruption of supply chains in the wake of Russia's aggression in Ukraine and the aggravation of climate change could lead to a rethink. In the US, the first support programs for the development of climate-friendly, innovative 'next-generation' fertilizers have been launched. This paper examines the interplay of patent law in concert with regulatory law and government funding tools in the area of innovative fertilizers. It starts from the hypothesis that other legal frameworks have a stronger influence on innovation activity than patent law at the moment. But this could change if the regulatory framework were to impose stricter requirements for the use of fertilizers. [ABSTRACT FROM AUTHOR]

The present paper reviews the most recent advances regarding the effects of chemical and organic fertilizers on soil microbial communities. Based on the results from the articles considered, some details are presented on how the use of various types of fertilizers affects the composition and activity of soil microbial communities. Soil microbes have different responses to fertilization based on differences in the total carbon (C), nitrogen (N) and phosphorus (P) contents in the soil, along with soil moisture and the presence of plant species. These articles show that the use of chemical fertilizers changes the abundance of microbial populations and stimulates their growth thanks to the nutrient supply added. Overall, however, the data revealed that chemical fertilizers have no significant influence on the richness and diversity of the bacteria and fungi. Instead, the abundance of individual bacterial or fungal species was sensitive to fertilization and was mainly attributed to the changes in the soil chemical properties induced by chemical or organic fertilization. Among the negative effects of chemical fertilization, the decrease in enzymatic activity has been highlighted by several papers, especially in soils that have received the largest amounts of fertilizers together with losses in organic matter. [ABSTRACT FROM AUTHOR]

The aim of this paper is to assess the potential impacts of different fertilizer subsidy reform options on the performance of the Iranian crops production sector. This is achieved using a Regional Crop Programming (RCP) model, based on Positive Mathematical Programming, which includes in total 14 crop activities and encompasses 31 administrative regions. The RCP model is a collection of micro-economic models, working with exogenous prices, each representing the optimal crop allocation at the regional level. The model is calibrated against observed data on crop acreage, yield responses to nitrogen application, and exogenous supply elasticities. Simulation results show that a total removal of nitrogen fertilizer subsidies would affect the competitiveness of crops with the highest nitrogen application rates and lead to a slight reduction of national agricultural income, at approximately 1%. This effect, which is more pronounced at the regional level, is driven by area reallocation rather than land productivity. The reallocation of nitrogen fertilizer subsidy to only strategic crops boost their production and income but increase disparity among regions and affects negatively welfare compared to the current universal fertilizer program. The transfer efficiency analysis shows that both target and universal simulated options are inefficient with an efficiency score below one. [ABSTRACT FROM AUTHOR]

Modern agriculture poses new challenges related to the increase of the need of sustainable development of the agrarian sector, and rural territories, respectively. The use of large amounts of chemical preparations in agriculture inevitably hides a number of possibilities for dangers, both for all mankind and for the natural environment. The main goal of this article is to analyze and evaluate the current state of use of pesticides and fertilizers in Bulgaria, as part of the agro-ecological indicators affecting the climate and natural ecosystems. As a result from the research carried out we found that the levels of pesticide use in Bulgaria are below the average, but the last years are marked by a tendency for gradual increase of the areas of the used quantities of nitrogen fertilizers, manure and organic fertilizer, and a deficit in the Phosphorous balance in soil was noted. We need lowering of the degree of ecological risks related to use of pesticides and fertilizers in Bulgaria. This way the results will be multiplied for achieving higher level of economic, social and ecological sustainability in the development of individual rural territories. [ABSTRACT FROM AUTHOR]

Nitrogen is a vital ingredient for plant development and growth. It is one of the most crucial indicators of soil fertility and crop growth conditions. For the monitoring of nitrogen loss patterns and the development of crop nitrogen fertilizer application strategies, an accurate determination of soil nitrogen concentration can be a valuable source of information. For the advancement of precision agriculture and the preservation of the natural ecological environment, an accurate, quick, and low-cost determination of soil nitrogen content and its variations is essential. This paper systematically analyzes and summarizes soil nitrogen detection methods by compiling and analyzing the relevant literature, comparing the advantages and disadvantages of various methods, and concluding with a discussion of the most significant challenges and future research trends in this field. This study provides a helpful resource for understanding the current status, application constraints, and future developments of nitrogen-sensing technologies in precision agriculture. [ABSTRACT FROM AUTHOR]

Model and field studies generally posit that when the application rates of nitrogen fertilizer exceed crop needs, nitrous oxide (N2O) emissions will increase nonlinearly, though linear responses are also extensively reported by field studies. We conducted year-round measurements of crop yield, N2O and methane (CH4) fluxes for treatments of six nitrogen levels (0, 135, 270, 430, 650 and 850 kg N ha-1 yr-1 in the form of urea) in a typical irrigated wheat-maize rotation field in northern China. Linear models characterized the responses of cumulative N2O emissions to fertilizer rates well; therefore, the calculated N2O emission factors of 0.17 ± 0.03%, 0.73 ± 0.07% and 0.49 ± 0.06% for the wheat season, maize season and annual scale, respectively, were appropriate for the different fertilizer rates. The cumulative CH4 uptake by the soil tended to be enhanced at higher fertilizer rates (≥350 kg N ha-1) in the maize season whereas no effect was observed for the wheat season. The crop yields stopped increasing at fertilizer rates greater than 650 kg N-1 yr-1. When the annual fertilizer rates increased from 270 to 430, from 270 to 650 and from 270 to 850 kg N ha-1 yr-1, the crop yields increased only 4-15% (0.6-2.2t ha-1 yr-1), but cumulative N2O emissions increased 36-115% (0.9-3.0 kg N ha-1 yr-1). We recommend 270 kg N ha-1 yr-1 as the locally optimum fertilizer rate. Considering the N inputs by fertilization (270 kg N ha-1 yr-1), irrigation (4.3 ± 0.2 kg N ha-1 yr-1) and deposition (wet deposition: 30.5 ± 1.5 kg N ha-1 yr-1), the slightly positive soil N balance could maintain the current crop yield (>14 t ha-1 yr-1) and reduce the present high N2O emissions (>3.51 kg N ha-1 yr-1) of the local farmers' practice (fertilizer rate: >430 kg N ha-1 yr-1). [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper focusses on nitrogenous fertilisers in Germany and how they were distributed from the First World War into the 1930s. Since the availability of the fertilisers kept changing at a fast pace in the period under discussion here, the focus lies on policies concerning the production of nitrogen and the markets for nitrogenous fertilisers. The paper discusses the impact of the development of a (nearly) entirely new domestic nitrogen industry during the First World War on the market for nitrogenous fertilisers during the war and interwar period, up until the foundation of an international nitrogen cartel in 1930. [ABSTRACT FROM AUTHOR]

(Objective) Aggregation is an important soil health indicator modulating many soil functions including nutrient bioavailability and carbon sequestration. It is affected by a multitude of factors. The purpose of this paper is to study the effect of irrigation and nitrogen fertilization on soil aggregation and soil organic carbon. (Method) The experiment was conducted in a winter wheat field. It consisted of two nitrogen applications: 0 (N0) and 180 kg/hm2 (N180), two irrigation treatments: sufficient irrigation (F) and deficit irrigation using 65% of the water in F. In each treatments, we measured water-stable aggregates and soil organic carbon.(Result) 1 Deficit irrigation coupled with nitrogen fertilization increased water-stable macroaggregates with diameter ≥0.25 mm. Nitrogen fertilization increased organic carbon in the top 0~30 cm soil layer by more than 3.59% when irrigation was the same, while deficit irrigation increased organic carbon in the same soil layer by more than 2.86% when nitrogen fertilization was the same. 2 Soil moisture directly affected soil carbon, explaining 83.9% of the change in total organic carbon, while nitrogen indirectly affected soil carbon, explaining 46.89% of change in the total organic carbon. 3 The direct impact of water-stable aggregates on soil carbon was negative, while its direct influence was positive.(Conclusion) The effect of nitrogen fertilization on soil aggregation was modulated by irrigation. Nitrogen fertilization combined with deficient irrigation boosted carbon accumulation in the topsoil. [ABSTRACT FROM AUTHOR]

The continuous use of chemical fertilizers in agricultural field causes the degradation of soil qualities and increases environmental pollutions ultimately causing damage to human health. The use of biofertilizers is a promising alternative for the agricultural production. The objective of this paper was to prove that the application of biofertilizers can reduce the use of chemical nitrogen fertilizers without affecting the nitrogen requirement of the plants. My study was carried out with wheat seeds that was seeded in plant pots in alluvial soil. The bio-fertilizer contributed the nitrogen required by the plant reducing the use of chemical fertilizer significantly. [ABSTRACT FROM AUTHOR]

Ageratina adenophora originating from central America has flooded forests, pastures, and farmland in more than 40 tropical and subtropical countries, causing huge ecological disasters and economic losses. In this paper, we intended to use a complex inoculum composed of Pseudomonas putita and Clostridium thermocellum to in-situ compost A. adenophora debris and then to compare the phytotoxicity of extracts from uncomposted and composted A. adenophora (UCA and CA respectively) to barley seed germination and young seedling growth. A field experiment was finally conducted to reveal the effects of UCA and CA on barley nutrients uptake, yield, grain quality, soil enzyme activities, microbial biomass and biodiversity. In-situ composting sharply decreased 4,7-dimethyl-1-(propan-2-ylidene)-1,4,4a,8a-tetrahydronaphthalene- 2,6(1H,7H)-dione(DTD) and 6-hydroxy-5-isopropyl-3,8-dimethyl-4a,5,6,7,8,8a-hexahydronaphthal en-2(1 H)-one(HHO) from 2096.3 and 743.7 mg kg-1 in uncomposted A. adenophora to 194.4 and 68.19 mg kg-1 in composted A. adenophora. UCAE showed negative influences on seed germination performances (except lower rates on germination percentage). The mechanism may be the inhibition of bio-macromolecules hydrolysis (including proteins, starch, and phytin) in endosperms and their hydrolysates for forming new plants. CAE promoted seed germination and seedling growth, increased chlorophyll levels in leaves, and stimulated dehydrogenase and nitrate reductase activities in plants, while UCAE got opposite performance. Compared with chemical fertilizers, application of CA in combination with chemical fertilizers significantly improved plant nutrient uptake (nitrogen, phosphorus, and potassium), yield, grain quality, quantity of 16S rDNA sequences, richness and diversity of bacterial communities in contrast to UCA which behaved otherwise. Taken together, the use of the microbial agent to in-situ compost A. adenophora may be an effective approach for agricultural use of A. adenophora debris as a plant-friendly organic fertilizer, being undoubtedly worth advocating. [ABSTRACT FROM AUTHOR]

China implemented the Action Plan for the Zero Increase of Fertilizer Use in 2015, which led to a decrease in fertilizer use. However, Will fertilizer use continue to reduce? With data obtained from 2006 to 2017, the paper used the logarithmic mean Divisia index (LMDI) method to analyze the scale effect, intensity effect and structural effect of fertilizer use change in China from three aspects: crops, regions and fertilizer types. Our finding suggests that (1) The intensity effect was the most critical factor affecting the decline in fertilizer use in China. (2) The sowing scale and fertilization intensity of grain, vegetables and fruits had the most significant driving effect on fertilizer reduction. (3) The three effects of each region were different in space, and the eastern region contributed most to the fertilizer decrement. (4) Nitrogen fertilizer and compound fertilizer had the most considerable influence on fertilizer reduction, especially in the sowing scale and fertilization intensity since 2009. The government should establish a fertilizer reduction management system, which includes scale control, intensity reduction, structural adjustment and other measures. [ABSTRACT FROM AUTHOR]

Purpose: No-till (NT) and fertilization are common land management practices in agricultural production systems to increase soil quality and crop yield. No-till can be reversed to tillage (termed tillage reversal, TR, in this paper) due to changes in management objectives. Materials and methods: The impact of NT, TR, and TR plus nitrogen (N) fertilization (TRN) treatments on the composition and structure of bacterial communities in a Gray Luvisol was studied in west-central Alberta, Canada. Results and discussion: The structure of bacterial communities was not affected by the TR treatment (compared with NT). The TRN treatment increased the relative abundance of some bacterial taxa groups, e.g., Gemmatimonadetes, Thermoleophilia and Solibacteres, that have chemolithotrophic nitrifying functions as compared with the TR treatment. The decreased relative abundance of some bacterial taxa groups, such as Alphaproteobacteria, Deltaproteobacteria, Spartobacteria, and Planctomycetia that have denitrifying functions, would change the soil's denitrification function in the TRN as compared to the TR treatment. There were more dominant bacterial taxa groups, and the bacterial community had greater inter-annual variations in the TRN than in the NT and TR treatments. Moreover, the function of bacterial communities was affected by the TRN as compared to the NT and TR treatments, based on the predicted metagenomes. Conclusions: We conclude that when TR was applied to the soil with long-term N fertilization, which eliminates N limitation, altered soil bacterial community structure and function over TR applied to the studied Gray Luvisol without long-term N fertilization. Findings from our study have important implications for improving land management practices through tillage and N fertilization to enhance the soil's function and quality in agroecosystems. [ABSTRACT FROM AUTHOR]

Taking the black soil of northeastern cold land as the research object, this paper adopts the threefactor quadratic saturation D311 optimal design scheme, uses static black box-gas chromatography to analyse the irrigation season, nitrogen fertilizer and straw biochar to the impact of greenhouse gas emissions for N2O growing season in the northeast cold paddy field. This paper also studies the optimal water and fertilizer application scheme for N2O control. The results show that the effects of three factors on N2O emissions are as follows: nitrogen fertilizer > biochar > water. The irrigation and biochar have an inhibitory effect on N2O emissions, while nitrogen fertilizer has a promoting effect on N2O emissions. The performance is as follows: water + nitrogen fertilizer can promote the emission of N2O; water + biochar can inhibit the emission of N2O; nitrogen fertilizer + biochar can promote the emission of N2O. Combined with the yield, the integrated water and biochar optimization schemes, when controlling the increase of N2O growth season in paddy fields to not exceed 10% are as follows: The amount of irrigation is 4252~5531 kg/hm²; the nitrogen application rate is 103.30~117.35 kg/hm²; and the amount of biochar is 15.12~24.42 t/hm². [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central China Normal University is the property of Huazhong Normal University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Soil Science Annual is the property of Polish Society of Soil Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Agronomía & Ambiente is the property of Universidad de Buenos Aires. Facultad de Agronomia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Agricultural fertilizer use is widely acknowledged to be a leading cause of water pollution. Yet, no national estimates exist on the effect of fertilizer application on concentrations of agricultural pollutants in US watersheds. This paper employs a watershed‐level panel data on nitrogen and phosphorus pollution readings to examine the impact of fertilizer use on US water quality over a fifty‐five‐year time period from 1951 to 2005. Findings show that a 10% increase in the use of nitrogen and phosphorus fertilizers leads to a 1.52% increase in the concentration of nitrogen and a 1.37% increase in the concentration of phosphorus across watersheds. Results also indicate that there exists heterogeneity in nutrient pollution elasticity estimates across eighteen US water resource regions, ranging from 0.082 to 0.733 in the case of nitrogen and from 0.036 to 0.475 in the case of phosphorus. Combining our results with prior hydrology‐based studies, we find that a 100% increase in the use of nitrogen fertilizers in the Lower Mississippi water resource region expands the size of the hypoxic zone in the Gulf of Mexico by roughly 3,389 square miles, equivalent to about two‐fifths of the estimated size of the dead zone in the Gulf of Mexico. [ABSTRACT FROM AUTHOR]

This paper studied the relationships between utilization ratios and conversion rates of nitrogen, phosphorus and potassium for rice by data mining method based on data of " 3414 fertilizer field trials" of rice by published papers from national soil testing and recommendation since 2()05. The results and conclusions were as follows:

The increase, improvement and stability of agricultural production and therefore of food security in all agricultural areas (tropical, subtropical, temperate, etc.), is achieved by cultivating certain plants, creating optimal vegetation conditions for them through well-defined elements of technology, starting from the fundamental idea that man must cooperate with the environment, to consciously become a protector of it. Given these considerations and starting from the fact that there are relations of a varied and complex reciprocity between the properties of the soil and the main cultivated species, this paper presents, based on studies conducted during three experimentation years, within the theme "Research on pedoclimatic and anthropogenic factors that condition land productivity from the Low Plain of Banat" and carried out during doctoral school, several aspects regarding the physicalgeographical characteristics illustrated by the maize yields on a typical Chernozem soil, slightly gleyic, epicalcaric, medium clay loam/medium clay loam from the research field in Lovrin. Given these aspects regarding the existence of risks due to various manifestations of natural factors or irrational human interventions, in this paper the authors try to transfer descriptive theoretical activities to analytical activities that provide practical solutions for the use of nitrogen and phosphorus fertilizers on the maize crop. The importance of the research topic derives from the fact that the soil/land properties are differentiated in the territory, due to the variation of pedogenesis factors and conditions, as well as to the fact that in the plant production system the productive potential of the soil is combined with the applied human labour, integrated by plants in the biomass production. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Getting to know the natural conditions and the technological features for a certain crop presents a special economic and social importance, both for the big agricultural exploitation and for the small producer. Relations of a varied and complex reciprocity are established between the properties of the soil and the main technological elements, fact shown by the level of wheat yields in the period 2016-2019, on a typical Chernozem soil, slightly gleyic, epicalcaric, medium clay loam/medium clay loam from Lovrin, Timis County. Regarding these considerations, the paper presents several aspects regarding the role and the physical-geographical characteristics of nitrogen and phosphorus fertilizers on the wheat production, based on studies with the theme "Research on pedoclimatic and anthropogenic factors that condition land productivity from the Low Plain of Banat" carried out during the doctoral school, respectively from September 28, 2016 and until now. The research consists of the accumulation of scientific data regarding the evolution of some components of agricultural land productivity, related to the cosmic-atmospheric and telluric-edaphic supply, necessary to substantiate current crop technologies for their efficient use through a thorough knowledge. Thus, the paper presents the results regarding the influence of nitrogen and phosphorus fertilizers on the wheat production in the agricultural period 2016-2019, in the physicalgeographical and climatic-edaphic conditions from the Low Plain of Banat. Taking into account these aspects regarding the existence of risks, due to various manifestations of natural factors and irrational human interventions, in this paper we tried to transfer the descriptive theoretical activities to analytical ones that lead to practical solutions related to the sustainable management of edaphic resources. The research is in line with the substantiation of sustainable agriculture systems, responding to the requirements of establishing the scientific database necessary to substantiate some technologies and the elaboration of integrated agroecosystem management measures. The importance of this paper derives from the fact that the soil/land properties are differentiated in the territory, both by the variation of the pedogenesis factors and conditions, and by the fact that in the plant production system the productive potential of the soil intersects with the human effort. Hence, we can talk about a cultural technically-economically conditioned productivity, a result of the contribution of soil, climatic factors, human labour, investments with water and fertilizers, quality seed, all vitally integrated by plants in the biomass production. [ABSTRACT FROM AUTHOR]

Nitrogen fertilizers are necessary, because thanks to them, crop production is improved. After water and temperature, it is considered as the third most important factor in the production of plant-based foods. Urea as a fertilizer, has the advantage of providing a high nitrogen content (46%), which is essential in the metabolism of the plant. The biggest disadvantage is the loss of nitrogen (N) in the form of ammonia gas (NH3), coming from its decomposition when applied to the soil. Slow-release urea is used to reduce volatilization losses after the hydrolysis phase and by leaching after ammonium nitrification. To reduce volatilization losses and maintain an adequate availability of N in the soil, different agronomic management strategies have been evaluated. The triamide N-(nbutyl) thiophosphoric (NBPT), urease inhibitor, temporarily prevents the enzymatic degradation of urease and minimizes the loss by volatilization of NH3, thereby increasing the absorption of N from fertilizer by the crop. The study was carried out during 2018. The paper elaborated addresses the role of N in cultivated plants, some ecological implications, the use of urea and especially a compilation of the characteristics of NBPT urea and of the most relevant research on the use of this fertilizer and its impact on increasing yield in annual crops. [ABSTRACT FROM AUTHOR]

The study evaluated the variation in the efficiency of nitrogen use from mineral fertilizers, associated with foliar fertilization in wheat, based on biological yield. Two specific indicators (Agronomic Efficiency - AE, Partial Factor Productivity - PFP) were calculated to quantify the efficiency of nitrogen use. The study was organized within the Didactic and Experimental Resort, BUASVM Timisoara. The 'Alex' wheat cultivar was cultivated, under the conditions of a chernozem type soil, medium fertility, and non-irrigated culture system. The 2020 – 2021 agricultural year was taken into account. Biological yield (BY, g m-2 ) was evaluated at physiological maturity (BBCH code 9, Senescence). Polynomial models of the 2nd degree described the variation of BY in relation to nitrogen (N) on each level of foliar fertilization (Super Fifty – SF), in differentiated conditions of statistical certainty (p<0.05 for the SF2 variant). There was an increasing variation in the AE and PFP values associated with foliar fertilization (SF), up to the level of SF2 and SF3 variants (2 – 3 L ha-1 ), followed by a decreasing trend. The regression analysis led to obtaining an equation-type mathematical model that described the BY variation in relation to N and SF, as a direct and interaction effect, under statistical safety conditions (p<0.001, R²=0.957). Based on the values of the obtained equation coefficients, the optimal doses were calculated (xopt=137.05 kg ha-1 N active substance, yopt=2.92 L ha-1 SF, concentration 1.168 %). [ABSTRACT FROM AUTHOR]

The research was conducted on the research field of Lviv National Agrarian University on dark gray podzolic light loamy soil. Hydrothermal conditions differed from the average of many years data by more precipitation. In 2019, during the growing season it fell by 53 mm above the rate, in 2020 - by 129 mm, in 2021 - by 73 mm. The aim of the research to define the amaranth nutrition system in conditions of sufficient and excessive moisture, seven rates of mineral fertilizer application were studied: N0P0K0, N40P20K40, N8040K80, N120P80K160, N160P80K120, N200P80K120, N120P80K160. Under the influence of fertilizers, plant height increased from 147.1 cm to 208.2 cm, panicle length - from 32.2 cm to 71.7 cm, seed weight from one plant - from 12.9 g to 27.8 g, weight of 1000 grains - 0.86 g to 0.91 g. The number of plants before harvest was in the range of 18-20 plants/m². Increasing of the application rate of mineral fertilizers from N0P0K0 to N200P80K160 provides the increase of the yielding capacity of amaranth grain of the variety Kharkiv 1 from 2.31 t/ha to 4.88 t/ha, or by 2.57 t/ha. Yield depended mostly on nitrogen fertilizers, application of N40 on variants with the rate of N120P40K80 and N2000P80K120 fertilizers resulted in a further increase of the yield by 0.41 t/ha and 0.34 t/ha. Increasing the potassium rate by K40 on variant N200P80K160 did not provide a significant (0.04 t/ha) increase of the yield. The highest level of yielding capacity is formed by the following structural elements: grain weight from one plant - 27.8 g and number of plants - 18 p/m². [ABSTRACT FROM AUTHOR]

Canadian nitrogen (N) fertilizer use has more than doubled since 1990 (1.2 to 2.9 MtN by 2021). Consequently, a better understanding of this trend is needed. A comprehensive set of recommended N rates (RNRs) that agreed with the fertilizer sales data from 1996 and 2001 was compared with the Fertilizer Use Survey (FUS). The FUS was conducted from 2014 to 2021, with 2017 being the most representative year for these data. Using non-parametric statistics, confidence intervals were derived from the histograms used to present the FUS data. N application rates from the RNR for canola, spring and Duram wheat, and oats in the west were all below their respective FUS confidence intervals, whereas N application rates for grain corn showed almost no difference in N use between the RNR and FUS. Crop-specific N application rates interpolated from the RNR and FUS were integrated over their respective crop areas and plotted against national fertilizer sales records from 1990 to 2021. The rapid increase in N use between 2001 and 2017 (0.89 MtN), 90% of it (0.80 MtN) in Western Canada, was primarily due to the increased application rates per crop, rather than crop area changes. The RNR-FUS interpolations were a good approximation of N sales records and could improve farm GHG emissions modelling. The economically important crops in Western Canada should be the main focus for N-related GHG reduction measures, but production losses need to be avoided. [ABSTRACT FROM AUTHOR]

In order to the yield maintenance along with environmental protection, the replacement or combination of chemical fertilizers with organic ones has received increasing attention recently. However, the yield and quality of production in aromatic plants differ from other plants. The present experiment was conducted for 2 years with the aim of evaluating the potential of vermicompost instead of nitrogen fertilizer for the production of geraniums without reducing its perfume quality. Regarded to the macronutrients, essential oil, and shoot yield, geranium treated with 20 ton ha−1 vermicompost and 16 ton ha−1 vermicompost + 40 kg ha−1 nitrogen had the best condition compared to other fertilizer regimes. Geranium is a perennial plant; hence the traits related to plant growth and yield were higher in the second harvest. Besides that, compared to treatments with a high amount of chemical nitrogen, the effects of vermicompost on the quality and quantity of geranium in the second yield were more effective and sustainable. Moreover, these findings suggested that an appropriate proportion of organic substitution not only provides uptake nutrients but also improves the essential oil yield and chemical composition. In fact, increasing the level of vermicompost resulted in improved oxygenated monoterpene content in geranium essential oil. According to the results of this study, cow manure-derived vermicompost could be a suited and sustained replacement for nitrogen inorganic fertilizer without any significant reduction in the quality and quantity of geranium products. Thus, it can be a practical step to reduce production costs, and environmental issues own to chemical fertilizers, particularly in aromatic plant cultivation. [ABSTRACT FROM AUTHOR]

The nitrogen (N) and phosphorus (P) released from different fertilizers to soil solution is a factor that affects soil fertility and plant growth. To evaluate the impacts of amending soil with organic, chemical and bio-fertilizers solely or in combinations for uprising N, P available contents in soil and increasing the growth of black cumin (Nigella sativa L) plants. The consequences of these additives on soil chemical properties were a matter of concern herein. To attain this aim, incubation and a pot experiment was conducting at 50% level of adding rabbit manure and ureaform together or both separately, control without fertilization and bio-fertilizer single in a randomized block design which considering six equations (Zero-order, first-order equation, second-order equation, Pseudo-second-order, power function, and parabolic diffusion model) were used to describe variations among released N and P with incubation time. The results demonstrated that using chemical, organic, and bio-fertilizer resulted in considerable decrease in soil pH and increases in organic matter (SOM) and nutrients availability (N and P) by time progress for all treatments. Compared to other equations, the pseudo-second models provided a better description of the kinetics of changes in released N and P contents with time, with R² ranging from 0.99 to 1.00. The results show that the application of 50% Rabbit manure + 50% Ureaform + Bio-fertilizer (RUBF) significantly enhanced parameters of black cumin plants such as shoot dry weight, plant height, and stem diameter, chlorophyll a, b, and carotenoids ratio, dry weight capsules, number of capsules, and seed weight/plant. Our study is useful when using rabbit manure, ureaform and bio-fertilizers. That can be improving soil chemical properties, supplying available nutrients, the release kinetics and the factors related to the release of nutrients from these fertilizers are essential in planning strategies of nutrient management, additionally, boosted the growth, plants quality, yield and photosynthetic pigments. [ABSTRACT FROM AUTHOR]

The cultivation of salt-tolerant rice (sea rice) along beaches has become an effective measure for the restoration and utilization of saline-sodic land, so this paper studies the effects of irrigation and nitrogen fertilization on soil Na+ in root zone and sea rice yield, and provides a scientific basis for planting sea rice. A pot experiment (two-factor split plot) of sea rice with salt stress (10 g NaCl/kg soil) was carried out. The main plot consists of three types of irrigation methods: flooding irrigation (F), intermittent irrigation (I), and controlled irrigation (C). The subplots are three types of nitrogen fertilizers: urea (U), controlled-release urea (R), and mixed fertilizer (M) with U and R. The results showed: (1) The soil water-soluble Na+ of MI was significantly smaller than that of other treatments with NaCl, but the Ca2+/Na+ and Mg2+/Na+ were opposite. (2) The nitrogen uptake and dry weight of rice of MI were significantly larger than those of other treatments with NaCl, and were respectively 23% and 32% higher than UI, 49% and 16% higher than MF, 56% and 38% higher than UF, 75% and 61% higher than RI, 76% and 50% higher than RF. (3) The sea rice yield of MI was increased by 105%, 154%, 262%, 338%, and 428% compared with MF, RF, UF, RI, and UI, respectively. Therefore, the MI can effectively reduce the Na+ and increase the Ca2+/Na+ and Mg2+/Na+ in root layer soil, and promote the nitrogen absorption and production of sea rice. So the article recommends that M and I methods should be adapted to plant sea rice on coastal saline-sodic soil. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to explore the feasibility of reducing the amount of nitrogen fertilizer and a reasonable nitrogen reduction model under late sowing wheat in the Jianghan Plain. 【Method】 Field experiments were conducted with Zhengmai 9023 under traditional and late sowing date with three nitrogen treatments differing in ratios of basal to topdressing. The changes in wheat yield and its constituent factors and nitrogen related indicators were compared across treatments. 【Result】（i） Under the same nitrogen application rate and base-topdressing ratio, grain yield, panicle number and 1000-grain weight were significantly reduced delayed the sowing date. Reduced total dry matter accumulation during flowering and maturity under late sowing was due to the decrease in dry matter accumulation in leaves and stem sheaths; The dry matter accumulation in spike did not show significant change. The changes in dry matter accumulation at maturity were related to leaves, stem+sheaths and grain husk+spike axis. Under the same nitrogen application rate and base-topdressing ratio, the nitrogen accumulation in wheat at flowering and maturity decreased as well; Nitrogen accumulation in flowering leaves of increased under late sowing, but nitrogen accumulation in stem+leaf sheath, ripe leaves and ripe grain husk+spike axis decreased. Under the same nitrogen application rate and base-topdressing ratio, the spike formation rate and nitrogen use efficiency were significantly reduced under late sowing.（ii）Under different nitrogen fertilization treatments and the same sowing date, nitrogen fertilization can be reduced from 180 to 150 kg/hm² under late sowing with insignificant change in yield decreased by 3.33 kg/hm²（M1） and 293.34 kg/hm²（M2） in 2019—2020; 158.67 kg/hm²（M1） and 13.50 kg/hm²（M2） in 2020—2021. The reduction was much lower than that of normal sowing, and the reason was that the number of spikes and grain number per spike were stable when the nitrogen application rate was reduced from 180 to 150 kg/hm², and the 1000-grain weight increased to some extent. Further reducing the amount of nitrogen applied, the yield change under the two sowing dates did not reach a significant level. Under the same base-topdressing ratio, reducing nitrogen application rate, the nitrogen accumulation in the stem+leaf sheath and spike at the flowering stage and grain husk+spike axis were significantly reduced, but dry matter accumulation did not change significantly. Under the same sowing date and base-topdressing ratio, reducing nitrogen application rate, spike formation rate increased significantly, M1 nitrogen utilization efficiency increased significantly, and M2 nitrogen utilization efficiency remained stable. 【Conclusion】Under the conditions of continuous optimization of nitrogen fertilizer management mode, the yield of late sowing wheat under nitrogen reduction treatment was not significantly reduced compared with normal nitrogen yield, but the spike formation rate and nitrogen use efficiency were significantly improved. After a delay of 20 days, the recommended nitrogen fertilizer management model is that the ratio of base to topdressing is m（base fertilizer）∶ m（top dressing before winter）∶ m（top dressing at jointing stage）=1∶1∶1, and the nitrogen application rate can be reduced from the normal nitrogen application rate to 150 kg/hm². [ABSTRACT FROM AUTHOR]

This study evaluated the use of nitrogen in wheat crop, in terms of Agronomic Efficiency (AE) and Partial Factor Productivity (PFP). The experiment was conducted in the specific conditions of the Banat University of Agricultural Science and Veterinary Medicine of Timisoara (BUASVM), Timis County, Romania. Nitrogen (N) was provided on the basis of ammonium nitrate, in the range 0 - 250 kg a.s. ha-1, in 11 experimental variants (T1 to T11). The AE index varied between 14.631 (T2) and 9.138 (T11), with a maximum (27.211) corresponding to the N75 dose (T4). The PFP index recorded decreasing values from 90.497 (T2) to 16.725 (T11). The AE index variation in relation to N was described by the polynomial equation of degree 4 (R² = 0.975, p <0.01), and the AE index variation according to Y was described by a polynomial equation of degree 3 (R² = 0.722, p = 0.0233). In relation to the calculated progressive increase yield (ΔPY) the AE variation was described by a linear equation (R² = 0.780, p <0.001). The PFP index variation in relation to N was described by a polynomial equation of degree 3 (R² = 0.994, p <0.001), and in relation to N and Y, as simultaneous influence, was described in statistical safety conditions (R² = 0.885, p = 0.0144). [ABSTRACT FROM AUTHOR]

Sesame (Sesamum indicum L.) is grown mainly in the tropics. It is typically grown by smallholders with nearly all of its production in developing countries. It is an important source of high-quality oil and protein. Inappropriate use of fertilizers and monocropping are among the major production constraints. The objective of this paper is therefore to review the effect of N fertilizers on sesame growth and productivity. Growth and yield of sesame are greatly influenced by the application of N fertilizer. In most of the sesame-producing countries, optimum seed yield of sesame was obtained from application of 46–100 kg·N/ha. Adequate nitrogen fertilization also improves uptakes of other nutrients, particularly P and K and some micronutrients. Preemergence application of mobile nitrogen (urea) is less efficient due to losses. Mobile form of N fertilizer became available within two days for the crop. Split N applications where the N fertilizer is applied at different growth stages of the crop increases productivity. Side-dress application is one of the easiest ways to maximize nitrogen use efficiency. N fertilizers should be placed 3–5 cm deeper than the seeds and 5–10 cm apart from the plant for side dress but not far than 20 cm. Under optimal environmental conditions, nitrogen fertilizer has no effect on phonological traits but on the growth parameters. In the potential areas, application of 46–100 kg·N/ha gives maximum yield and lowering the application of N to less than 46 kg·N/ha in marginal areas is economical. [ABSTRACT FROM AUTHOR]

Huang-Huai-Hai region is the major superiority area of planting industry and breeding industry in China. With the increasing attention to the rural environment problems caused by crop straw and livestock manures, it is important to analyze “raising by planting” in Huang-Huai-Hai region, realize agricultural waste comprehensive utilization, and implement green development. “Raising by planting” was the core idea of this paper. The “raising by planting” calculation methods were as follow. First, technical regulations for production of wheat-corn and field research results in Hebei, Henan and Shandong provinces were used to summarize production model of wheat-corn in Huang-Huai-Hai region. So the conventional fertilization could be defined. According to test results of researches, this paper determined the amount of partial replacement of chemical fertilizer by organic manures. At the same time, thermophilic aerobic composting was chosen as techniques of livestock manure comprehensive utilization. The untreated amount of livestock manures was calculated. Then, the quantities of different species of livestock and poultry were calculated. According to the technical regulations, the amount of nitrogenous fertilizer were 532.5, 562.5 and 575 kg/hm2 in Hebei, Henan and Shandong provinces. The ratio of partial replacement of chemical fertilizer by organic manures was 30%. So the amount of replacement were 159.75, 168.75 and 172.5 kg/hm2. At the same time, there were no influence on grain security after the replacement of chemical fertilizer by organic manures. Due to the additional application of organic manures promoted soil nitrogen leaching risk, the environmental risk assessment of nitrogen in arable farmland was used. Nitrogen input mainly consisted of nitrogenous fertilizer, organic manure converted from livestock manures, seed, straw returning, atmospheric dry and wet deposition and irrigation water. Nitrogen output mainly consisted of grain and straw. Grade of environment risk in farmland in Hebei, Henan and Shandong provinces were all medium risk. Nitrogen loss rate of thermophilic aerobic composting fromlivestock and poultry manures was 42.26%. Other calculation parameters of livestock and poultry production, such as feeding period, population structure, were defined by many research papers. So in production model of wheat-corn in Huang-Huai-Hai Region, 6 dairy cows, or 18 beef cattle, or 47 to 51 swine, 731 to 789 laying hens or 8062 to 8705 broilers per hectare were land carrying capacity. Besides, at the field scale, various factors, such as soil fertility and soil microbial, might affect the ratio of partial replacement of chemical fertilizer by organic manures. So more researches were needed in the amount of replacement. On account of medium environment risk in farmland, lowering the risks was necessary. Nitrogen input structure: 46.3% chemical fertilizer, 27.5% straw returning, 19.8% organic manure, 4.0% atmospheric dry and wet deposition, 2.0% irrigation water and 0.4% seed. So reducing straw returning was one of risk solutions. In simulation results, reducing corn stalk or wheat straw both lowered environment risk effectively. The results provide a reference for planting and raising combination in Huang-Huai-Hai region. [ABSTRACT FROM AUTHOR]

The agricultural sector has become an important emitter of greenhouse gases in China. The CO2 emissions in the western undeveloped region have attracted less attention than those in the eastern developed region in China. In this paper, the change in carbon footprint (CF) caused by agrochemical and agricultural energy inputs, the contributions of various inputs to the total carbon footprint (TCF), and the different changing trends between carbon intensity in output value (CV) and carbon intensity in area (CA) in Qinghai province were studied based on the data for agrochemical and energy inputs over 1995–2016. The change in TCF had a roughly stable period over 1995–1999, a slowly decreasing period over 2000–2007, and a rapidly increasing period over 2008–2016, which generally synchronize with the periods of before the Grain for Green Policy (GFGP), during the GFGP, and after the GFGP, respectively. The chemical nitrogen fertilizer and energy inputs were the principal factors influencing the TCF. The N fertilizer was the highest contributor to the TCF and contributed more to the relatively lower TCF during the GFGP in the study area. The relative CF caused by plastic film and diesel input in the study area increased faster than that in the whole country. The CV declined, with a mean of 0.022 kg carbon equivalent (CE)/Chinese Yuan (CNY), which was 55.59% of the mean CV in China over 1995–2016; inversely, the CA obviously rose after 2007, with a mean of 5.11 kg CE/ha, which was only 1.94% of the mean CA in China from 1995 to 2016. Compared with the whole country, Qinghai province generally had a higher rate of increase of carbon efficiency accompanied by a higher rate of increase of CA. The improvements of local agricultural activities should aim to keep a balance between higher carbon efficiency and lower CA in the study area. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Field & Vegetable Crops Research / Ratarstvo i povrtarstvo is the property of Institute of Field & Vegetable Crops and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

China's greenhouse vegetable production has rapidly expanded over 30 years. We reviewed 476 papers from 1990 to 2021 to investigate the changes in the conventional application rate (CAR) and nutrient use efficiency (NUE) of fertilizers. The results indicated a decrease in the CAR of nitrogen (N) and phosphorus (P) fertilizers from 1993 to 2020. In contrast, the CAR of potassium (K) fertilizer exhibited an initial increase from 1993 to 2005, followed by a decline from 2006 to 2020. The CAR of fertilizer was higher in the warm area around the Bohai Sea and the rainy subtropical area in the Yangtze River basin compared to other areas. Additionally, it was higher in fruit vegetables than in other types of vegetables. Compound and water-soluble fertilizers replaced single-nutrient fertilizers gradually, and the proportion of organic nutrients decreased in the recent decade. The NUE of fertilizers decreased during 2006–2010 and showed an upward trend after 2010. Controlled release/slow-release fertilizer emerged as the most effective measure for enhancing the NUE of N fertilizer, demonstrating an average increase of 66.71 %. Combining multiple single measures was also effective. Our findings suggest that an optimal fertilizer management is a key factor to maintain the long-term productivity in greenhouse vegetable production. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aims: The application of biochar amendments or organic manure substitutions can alleviate the harmful environmental effects of inorganic fertilizers on agroecosystems, whereas they can also affect soil microenvironments which have not been fully explored on the Loess Plateau. Methods: Our field experiments consisted of no fertilizer (N0), N application (150 kg N hm−2, N150), 30% organic manure replacing N fertilizer (NO30), no fertilizer plus 10 t hm−2 biochar (N0 + C), N application plus 10 t hm−2 biochar (N150 + C), and 30% organic manure replacing N fertilizer plus 10 t hm−2 biochar (NO30 + C). The nutrient levels, bacterial community structure, ecological network, assembly process of bulk soil and rhizosphere at jointing and flowering stages, and crop yield in broomcorn millet field were investigated. Results: Fertilizer regimes and biochar amendments increased the bulk soil and rhizosphere nutrient contents than no fertilizer and no biochar. NO30 significantly improved the rhizosphere observed OTUs at jointing and flowering stages. Biochar amendments increased the observed OTUs of bulk soil and rhizosphere than no biochar. N150 and NO30 had a lower network complexity than N0 treatment, whereas N150 + C had the most complex network. Biochar amendments had more deterministic process than fertilization regimes. Meanwhile NH4+-N content was the major factor shaping the bacterial diversity, structure, and assembly process. NO30 + C has the highest yield of broomcorn millet. Conclusions: Compared with fertilizer regimes, biochar amendment had higher nutrient contents and observed OTUs of bulk soil and rhizosphere, and it also had a more substantial influence on the bacterial community structure and network stability. [ABSTRACT FROM AUTHOR]

[Objective] In order to explore the effects of low nitrogen stress on the growth and soil nutrients of tartary buckwheat in the hilly and gully regions of the Loess Plateau, the present paper determined plants and soil characteristics of tartary buckwheat with different nitrogen stress among the whole growth period It could provide a scientific basis for the optimal management of farmland nitrogen fertilizer in the loess hilly and gully region. [Method] The study took different nitrogen buckwheat (Heifeng No. 1, HF, intolerant to low nitrogen, Diqing Tartary Buckwheat, D Q, tolerant to low nitrogen) as the research objects, and set 3 levels of nitrogen application as follows : 0 kg/hm² (NO, no nitrogen treatment), 80 kg/hm² (Nl, low-nitrogen treatment), 160 kg/hm² (N², normal nitrogen treatment). Plant indexes (plant height, stem thickness, leaf area) and soil characteristics (soil water content, pH, organic matter, alkali-hydrolyzed nitrogen, available phosphorus, available potassium, total nitrogen, total phosphorus, total potassium) were determined during the whole growth periods. [Result] (i) Cultivar, nitrogen treatment and the interaction between the two had extremely significant effects on tartary buckwheat plants (P < 0. 01 ). Under Nl treatment, the plant height, stem thickness and leaf area of DQ in the seedling stage were 9. 7 %, 10. 5 %, and 17. 7 % higher than that of HF. The plant height and stem thickness of DQ in the flowering stage were 9. 5 % and 7. 4 % higher than that of HF. The stem thickness and leaf area of DQ were 5. 4 % and 3 6. 2 % higher than those of HF. (ii) The cultivars, nitrogen treatments and the interaction between the two had a significant impact on soil nutrients (P < 0. 01). After the growth period, the soil nutrient indexes of the two cultivars were lower than those of the sowing period, but soil organic matter, available nitrogen, available phosphorus, available potassium, total nitrogen, and total potassium of DQ were higher than those of HF under Nl treatment of98. 8%, 11. 6%, 44. 7%, 11. 6%, 80. 41%, 4. 2%, respectively. [Conclusion] The DQ (low nitrogen tolerant) has better water conservation and green manure benefits than HF (intolerant to low nitrogen) as its larger leaf area and stem thickness could buffer the direct erosion of rainfall on the ground and resist wind to prevent plant lodging. In addition, the rhizosphere soil nutrient content of DQ was higher than HF after being harvested which could reduce the fertilizer consumption in the next season and was also more conducive to the sustainable development of agriculture. [ABSTRACT FROM AUTHOR]

[Objective] In order to explore the effects of low nitrogen stress on the growth and soil nutrients of tartary buckwheat in the hilly and gully regions of the Loess Plateau, the present paper determined plants and soil characteristics of tartary buckwheat with different nitrogen stress among the whole growth period It could provide a scientific basis for the optimal management of farmland nitrogen fertilizer in the loess hilly and gully region. [Method] The study took different nitrogen buckwheat (Heifeng No. 1, HF, intolerant to low nitrogen, Diqing Tartary Buckwheat, D Q, tolerant to low nitrogen) as the research objects, and set 3 levels of nitrogen application as follows : 0 kg/hm² (NO, no nitrogen treatment), 80 kg/hm² (Nl, low-nitrogen treatment), 160 kg/hm² (N², normal nitrogen treatment). Plant indexes (plant height, stem thickness, leaf area) and soil characteristics (soil water content, pH, organic matter, alkali-hydrolyzed nitrogen, available phosphorus, available potassium, total nitrogen, total phosphorus, total potassium) were determined during the whole growth periods. [Result] (i) Cultivar, nitrogen treatment and the interaction between the two had extremely significant effects on tartary buckwheat plants (P < 0. 01). Under Nl treatment, the plant height, stem thickness and leaf area of DQ in the seedling stage were 9. 7 %, 10. 5 %, and 17. 7 % higher than that of HF. The plant height and stem thickness of DQ in the flowering stage were 9. 5 % and 7. 4 % higher than that of HF. The stem thickness and leaf area of DQ were 5. 4 % and 3 6. 2 % higher than those of HF. (ii) The cultivars, nitrogen treatments and the interaction between the two had a significant impact on soil nutrients (P < 0. 01). After the growth period, the soil nutrient indexes of the two cultivars were lower than those of the sowing period, but soil organic matter, available nitrogen, available phosphorus, available potassium, total nitrogen, and total potassium of DQ were higher than those of HF under Nl treatment of98. 8%, 11. 6%, 44. 7%, 11. 6%, 80. 41%, 4. 2%, respectively. [Conclusion] The DQ (low nitrogen tolerant) has better water conservation and green manure benefits than HF (intolerant to low nitrogen) as its larger leaf area and stem thickness could buffer the direct erosion of rainfall on the ground and resist wind to prevent plant lodging. In addition, the rhizosphere soil nutrient content of DQ was higher than HF after being harvested which could reduce the fertilizer consumption in the next season and was also more conducive to the sustainable development of agriculture. [ABSTRACT FROM AUTHOR]

Excessive fertilization reduces fertilizer efficiency and farm economic benefits, and causes various environmental problems. This study aimed to produce high grain yield and protein content for wheat production in China using a High Nutrient-use efficiency Based Fertilizer Recommendation method (High NUFER) and limits for crop nutrient physiological efficiency and partial factor productivity of fertilizer. A farm survey covering 1575 fields was carried out in 17 major wheat production provinces in China from 2015 to 2019. The on-farm information included wheat planting area, varieties, field management, soil nutrient status and fertilization status, and wheat plant and soil samples were also collected from farmers' fields for measurement and analysis. The High NUFER proposed in this paper was verified in 46 sites in 7 major wheat production provinces from 2020 to 2021. For the average grain yields > 6.0 t ha–1 and protein content ∼13.0% in major wheat production regions of China, the nutrient physiological efficiency of wheat should range from 36.5 – 36.8 kg kg–1 nitrogen (N), 261.3–273.9 kg kg–1 phosphorus (P), and 53.0–54.3 kg kg–1 potassium (K), and partial factor productivity of N, P, and K fertilizers should range from 35.9 – 41.9, 153.5–177.9, and 132.5–158.9 kg kg–1, respectively, when soil available nutrients ranged from 19.0 to 21.8 mg kg–1 available N (nitrate-N + ammonia-N), 22.4–26.1 mg kg–1 available P, and 153.9–157.3 mg kg–1 available K. Using the High NUFER, China should save 0.62 MT yr–1 N fertilizer, 0.36 MT yr–1 P fertilizer, and 0.22 MT yr-1 K fertilizer, with an additional economic benefit of 1.1 billion USD yr–1 and reduction in greenhouse gas (GHG) emissions of 8.91 MT CO 2 eq yr–1 in major wheat production regions. The High NUFER can reduce farmers' fertilizer input, thereby increasing economic benefits and decreasing GHG emissions. The High NUFER proposed in this paper has practical value for nutrient management in China and is a potential reference for other wheat-growing countries. • Limits were set for crop nutrient physiological efficiency and partial factor productivity of fertilizer at national scale. • Study offers the possibility of producing high yields with high protein content. • Established yield-protein content and nutrient efficiency relationships at a national scale. [ABSTRACT FROM AUTHOR]

Nitrogen fertilizers are essential inputs into modern agriculture, however the use of large amounts of mineral fertilizers in Italy caused, in the last three decades, severe environmental impacts such as eutrophication of waters and soils, loss of biodiversity, and drinking water pollution including human health risks. To date, regulatory instruments, such as the Nitrate Directive applied to reduce and manage mineral fertilizers showed scarce results in terms of environmental protection. Meanwhile the EU Common Agricultural Policy (CAP) subsidy scheme continues to encourage intensive agriculture and the national fiscal policy includes VAT reduction to 4% for mineral fertilizers. The aim of this paper is to propose a reform of direct and indirect fertilizers' subsidies considering multiple fiscal options to adjust and eliminate some harmful incentives. The elimination of direct subsides shows the ability to generate a financial effect of €252.54 million per year. As for indirect subsidies for chemical fertilizers, their fiscal remodelling by bringing back the VAT rate from 4% to 22%, has the ability to generate revenues for the state of €597.40 million. The proposed subsides reform has the capacity to generate a significant revenue for the state amounting to €849.94 million every year, which may be used for investments in organic farming and sustainable agriculture practices. [ABSTRACT FROM AUTHOR]