Forms Of Nitrogen Research Articles

Efficiency of molasses waste when growing potatoes (Solanum tuberosum) as a new promising organic fertilizer

It has been established that the waste of the alcohol and sugar industry (molasses innovative fertilizer) contains a complex of nutrients, which indicates the feasibility of their use as fertilizers for growing crops. This use of these types of waste will help solve the problem of their utilization, as they accumulate in significant volumes in the areas adjacent to the factories, in storage ponds. At the same time, the issue of reducing soil depletion of key nutrients due to the shortage of traditional organic fertilizers and the high cost of mineral fertilizers will be partially resolved. According to the results of field studies, the effectiveness of using waste in potato fertilization systems on soddy-loamy, bound sandy soil has been proven in order to obtain consistently high yields. In particular, it was found that the introduction of this type of waste at a rate of 10 t/ha ensures the formation of tubers weighing 92.7 g and 66 mm in diameter, and with a twofold increase in the rate — 109.3 g and 74 mm, respectively. These biometric parameters provided potato yields of 19.7 t/ha when using waste at a rate of 10 t/ha and 26.6 t/ha when using 20 t/ha. A positive effect on the quality indicators of potato tubers was recorded when using waste as fertilizer, in particular, the starch content was at the level of 16.6–16.7%. A positive effect of molasses innovative fertilizer on abStract 154 agroecological journal • no. 1 • 2023 the agrochemical parameters of the soil was also found, which is manifested in an increase in the content of nutrients in the tilth layer of soil (0–20 cm): nitrate forms of nitrogen (N–NO3) by 2.0–7.2 mg/kg, ammonium forms of nitrogen (N–NH4) — 0.4–1.1 mg/kg, mobile forms of phosphorus (P2O5) — 5.4–8.4 mg/kg and mobile forms of potassium (K2O) — 26.6– 40.6 mg/kg. The possibility of using waste in combination with mineral fertilizers was noted, which balances the fertilizer system and provides additional growth of potato tuber yield.

Transcriptome profiling of barley in response to mineral and organic fertilizers

BackgroundNitrogen is very important for crop yield and quality. Crop producers face the challenge of reducing the use of mineral nitrogen while maintaining food security and other ecosystem services. The first step towards understanding the metabolic responses that could be used to improve nitrogen use efficiency is to identify the genes that are up- or downregulated under treatment with different forms and rates of nitrogen. We conducted a transcriptome analysis of barley (Hordeum vulgare L.) cv. Anni grown in a field experiment in 2019. The objective was to compare the effects of organic (cattle manure) and mineral nitrogen (NH4NO3; 0, 40, 80 kg N ha−1) fertilizers on gene activity at anthesis (BBCH60) and to associate the genes that were differentially expressed between treatment groups with metabolic pathways and biological functions.ResultsThe highest number of differentially expressed genes (8071) was found for the treatment with the highest mineral nitrogen rate. This number was 2.6 times higher than that for the group treated with a low nitrogen rate. The lowest number (500) was for the manure treatment group. Upregulated pathways in the mineral fertilizer treatment groups included biosynthesis of amino acids and ribosomal pathways. Downregulated pathways included starch and sucrose metabolism when mineral nitrogen was supplied at lower rates and carotenoid biosynthesis and phosphatidylinositol signaling at higher mineral nitrogen rates. The organic treatment group had the highest number of downregulated genes, with phenylpropanoid biosynthesis being the most significantly enriched pathway for these genes. Genes involved in starch and sucrose metabolism and plant-pathogen interaction pathways were enriched in the organic treatment group compared with the control treatment group receiving no nitrogen input.ConclusionThese findings indicate stronger responses of genes to mineral fertilizers, probably because the slow and gradual decomposition of organic fertilizers means that less nitrogen is provided. These data contribute to our understanding of the genetic regulation of barley growth under field conditions. Identification of pathways affected by different nitrogen rates and forms under field conditions could help in the development of more sustainable cropping practices and guide breeders to create varieties with low nitrogen input requirements.

Effect of municipal biowaste derived biostimulant on nitrogen fate in the plant-soil system during lettuce cultivation

A main concern of agriculture is to improve plant nutrient efficiency to enhance crop yield and quality, and at the same time to decrease the environmental impact caused by the lixiviation of excess N fertilizer application. The aim of this study was to evaluate the potential use of biopolymers (BPs), obtained by alkaline hydrolysis of the solid anaerobic digestate of municipal biowastes, in order to face up these main concerns of agriculture. The experimental trials involved the application of BPs (at 50 and 150 kg/ha) alone or mixed with different amounts (100%, 60% and 0%) of mineral fertilizer (MF). Three different controls were routinely included in the experimental trials (MF 100%, 60% and 0%). The effect of BPs on lettuce was evaluated by monitoring growth parameters (fresh and dry weights of shoot and root, nitrogen use efficiency), and the N-flux in plant-soil system, taking into account the nitrate leached due to over irrigation events. The activities of enzymes involved in the nitrogen uptake (nitrate reductase, glutamate synthase and glutamine synthase), and the nitrogen form accumulated in the plant tissues (total N, protein and NO3−) were evaluated. The results show that the application to the soil of 150 kg/ha BPs allows to increase lettuce growth and nitrogen use efficiency, trough stimulation of N-metabolism and accumulation of proteins, and hence to reduce the use of MF by 40%, thus decreasing the nitrate leaching. These findings suggest that the use of BPs as biostimulant greatly contributes to reduce the consumption of mineral fertilizers, and to mitigate the environmental impact caused by nutrients leaching, according to European common agricultural policy, that encourages R&D of new bioproducts for sustainable eco-friendly agriculture.

Influence of Cellulose on the Anoxic Treatment of Domestic Wastewater in Septic Tanks: Statistical Analysis of the Chemical and Physico-Chemical Parameters

Cellulose is a very common polymer in domestic wastewater (WW), representing a not negligible part of the organic substance contained in sewage. To date, many studies have highlighted the feasibility of reusing this compound in several ways (e.g., building sector, wastewater treatment, energy production, etc.) after its separation from domestic WW. However, studies about the impact of the absence of cellulose on the chemical and physico-chemical parameters of a biological process are still lacking. In this work, two pilot-scale plants were used to simulate an anoxic treatment of WW in septic tanks, with and without cellulose (CWW and NCWW, respectively), for three months. The results of the monitoring highlighted that T, pH, and electrical conductivity (EC) remained almost constants, in both cases. The Spearman correlation coefficients (SCC) for turbidity (TUR), total suspended solids (TSS), and color (COL) indicated a higher removal in the case of CWW (65%, 66%, and 56%, respectively). Organic substance and nitrogen forms showed a similar behavior with and without cellulose, but in the case of CWW, N-NH3 was highly negatively correlated with TUR (SCC: −0.54), TSS (−0.49), and COL (−0.39). A biological denitrification process was highlighted in both cases. Despite these differences, when statistically analyzing the trends of the chemical and physico-chemical parameters for CWW and NCWW, a significant difference due to the absence of cellulose was excluded. These results will be useful to the scientific community, as they exclude that the operational parameters of anoxic treatments and the effectiveness on pollutants removal can be affected in the case of preliminary cellulose separation from domestic WW for recovery/reuse purposes.

Optimum Strength and NH4+:NO3- Ratio of Nutrient Solution for Romaine Lettuce Cultivated in a Home Hydroponic System

Concentration of nitrogen, one of the major elements, and ratio of two nitrogen forms (NH4+ and NO3–) in the nutrient solution affect the quality and food safety of fresh vegetable produce. This study was conducted to find an appropriate strength and NH4+:NO3– ratio of a nutrient solution for growth and development of a Romaine lettuce (Lactuca sativa L. var. longiflora) ‘Caesar Green’, a representative leafy vegetable, grown in a home hydroponic system. In the first experiment, plants were grown using three types of nutrient solution: A commercial nutrient solution (Peters) and two strengths (GNU1 and GNU2) of a multipurpose nutrient solution (GNU solution) developed in a Gyeongsang National University lab. Plants grown with the GNU1 and GNU2 had greater shoot length, leaf length and width, and biomass yield than Peters. On the other hand, the root hairs of plants grown with Peters were short and dark in color. Tissue NH4+ content in the Peters was higher than that of the GNU1 and GNU2. The higher contents of NH4+ in this solution may have caused ammonium toxicity. In the second experiment, eight treatment solutions, combining GNU1 and GNU2 solutions with four ratios of NO3–:NH4+ named as 1, 2, 3 and 4 were used. Both experiments showed more growth in the GNU2 group, which had a relatively low ionic strength of the nutrient solution. The growth of Romaine lettuce showed the greatest fresh weight along with low tissue NO3– content in the GNU2-2. This was more advantageous in terms of food safety in that it suppressed the accumulation of surplus NO3– in tissues due to the low ionic strength of the GNU2 subgroup. In addition, this is preferable in that it can reduce the absolute amount of the input of inorganic nutrients to the nutrient solution.

ROLE OF NO IN SOFT PERIODONTAL TISSUES OF RATS DURING STRESS AND INFLAMMATION

Aim. To evaluate the activity of NO-synthase isoforms, the concentration of peroxynitrites and nitrosothiols in the soft tissues of the periodontium of rats under the conditions of modeling chronic stress against the background of lipopolysaccharide-induced inflammation. Methods. Experimental studies were performed on 24 male Wistar rats weighing 190–240 g. The animals were divided into 4 groups: 1 — control, 2 — chronic stress (ChrStr group), animals were kept above water for 1 hour every day for 30 days, 3 — animals that were intraperitoneally injected with 0.4 μg/kg of bacterial LPS of S. typhi (pyrogenal) (LPS group); 4 — animals that were simultaneously simulated chronic stress as in group 2 and administered LPS as in group 3 (ChrStr+LPS). The activity of inducible NO-synthase (iNOS), constitutive NO-synthase (cNOS), the concentration of nitrosothiols (S-NO), and concentration of peroxynitrites of alkali and alkaline earth metals (ONOO) were studied in the homogenate of the periodontal soft tissues of rats. Results. The activity of NOS in the soft periodontal tissues of rats under chronic stress simulation conditions, LPS administration, combined exposure to chronic stress and LPS was increased compared to control group. The concentration of ONOO- in the soft periodontal tissues of rats under chronic stress simulation conditions, LPS administration, combined exposure to chronic stress and LPS was increased compared to the control group. The concentration of nitrosothiols in the soft periodontal tissues of rats under the conditions of chronic stress simulation, LPS administration, combined exposure to chronic stress and LPS was decreased compared to the control group. Conclusions. The combined effect of bacterial lipopolysaccharide and chronic stress leads to increased production of nitrogen monoxide from inducible NO-synthase and elevates concentration of reactive forms of nitrogen, which creates possibility for development of nitrosative stress in the soft periodontal tissues.

Effect of Microbial Preparation and Biomass Incorporation on Soil Biological and Chemical Properties

In order to meet the global nutritional needs of a growing population, attempts are being made to develop strategies that can effectively offset the negative effects of intensive farming. The aim of this study was to investigate the effect of Effective Microorganisms (EM) preparation and organic matter incorporation on the soil microbiological and chemical features. The analyses included the number of heterotrophic bacteria, fungi, actinobacteria, cellulolytic, amylolytic and proteolytic microorganisms, and bacteria of the genus Azotobacter. The content of organic carbon, the total and mineral nitrogen forms of phosphorus, potassium, magnesium, and the pH were also determined. The application of an EM of higher dose combined with the manure and straw resulted in the highest abundance of heterotrophic bacteria (165.1 × 106 cfu g−1), actinobacteria (43.2 × 105 cfu g−1), cellulolytic (17.2 × 106 cfu g−1), and proteolytic bacteria (82.0 × 106 cfu g−1). The highest content of chemical parameters was always observed in the experimental variant, including biomass incorporation, accompanied by EM use. The novelty of our research is the analysis of the synergistic effect of the experimental factors studied on the microbiological and chemical parameters of arable soils.

Effects of heavy rain on the concentrations and forms of carbon, nitrogen and phosphorus in urban rivers of northern China.

Non-point source pollution caused by rainfall runoff is an important pollution source for river water. To explore the impact of heavy rain on urban river water environments, this paper studied the changes in carbon, nitrogen, and phosphorus levels, composition, and structure in the river water of Kaifeng, China, during the heavy rain in July 2021. The results showed that the concentrations of different forms of carbon, nitrogen, and phosphorus all increased under the effect of the heavy rain. The increase of phosphorus in the river was the largest, and that of carbon was the smallest. The most significant pollution from carbon, nitrogen, and phosphorus occurred in the HJ River. Colored dissolved organic matter (CDOM) was present in the form of macromolecules after the rain, and the degree of humification was deeper compared with before the rain. But heavy rain did not affect the CDOM composition in urban rivers. The spectral slope (SR) and the absorption coefficient at 240nm to 420nm (E2/E4) values showed that the CDOM was dominated by exogenous input after the rain, with endogenous pollution again becoming the main factor one week after the rain.

Advantages of growth and competitive ability of the invasive plant Solanum rostratum over two co-occurring natives and the effects of nitrogen levels and forms.

Atmospheric nitrogen (N) deposition has often been considered as a driver of exotic plant invasions. However, most related studies focused on the effects of soil N levels, and few on those of N forms, and few related studies were conducted in the fields. In this study, we grew Solanum rostratum, a notorious invader in arid/semi-arid and barren habitats, and two coexisting native plants Leymus chinensis and Agropyron cristatum in mono- and mixed cultures in the fields in Baicheng, northeast China, and investigated the effects of N levels and forms on the invasiveness of S. rostratum. Compared with the two native plants, S. rostratum had higher aboveground and total biomass in both mono- and mixed monocultures under all N treatments, and higher competitive ability under almost all N treatments. N addition enhanced the growth and competitive advantage of the invader under most conditions, and facilitated invasion success of S. rostratum. The growth and competitive ability of the invader were higher under low nitrate relative to low ammonium treatment. The advantages of the invader were associated with its higher total leaf area and lower root to shoot ratio compared with the two native plants. The invader also had a higher light-saturated photosynthetic rate than the two native plants in mixed culture (not significant under high nitrate condition), but not in monoculture. Our results indicated that N (especially nitrate) deposition may also promote invasion of exotic plants in arid/semi-arid and barren habitats, and the effects of N forms and interspecific competition need to be taken into consideration when studying the effects of N deposition on invasion of exotic plants.

Effect of Nano Urea Foliar Spray on Yield and Yield Attributes of Black Gram (Vigna mungo L.)

Foliar application of nano urea is a good option of nitrogen or a balanced dose of nitrogen to increase the yield of black gram. For that, this study was conducted to evaluate the performance of black gram (Vigna mungo L.) under two forms of nitrogen at the Bangladesh Institute of Nuclear Agriculture (BINA) sub-station experimental field, Chapainawabganj during September to December 2022. Black gram variety Binamash-2 and 3 treatments, viz. Control (no fertilizer) (T1), Farmers practice (recommended fertilizer application as basal dose and top dressing during active growth) (T2) and Nano urea (2-4 ml of nano urea (4 % N) in one litre of water and sprayed on crop leaves at its active growth stages) (T3) were used under randomized block design. Yield and yield contributing characters were significantly affected by different forms of nitrogen (urea). The highest grain yield was obtained with T3 which was 1587.33 kg per hectare whereas T1 had given the lowest yield (983.33 kg per hectare). It was obvious that grain yield of black gram can be increased substantially with the judicious application of nano urea as foliar spray during active growth stages.

Distribution of nitrogen (N) and phosphorus (P) in seasonal low-oxygen marine ranching in northern Yellow Sea, China.

Seasonal low-oxygen in marine ranching in the northern Yellow Sea has been one of the major environmental problems in coastal waters in recent years. Nitrogen (N) and phosphorus (P) are important nutrients, which are susceptible to the concentration of dissolved oxygen (DO). This article studied the effects of low-oxygen on nutrients represented by N and P fractions in marine ranching in the northern Yellow Sea. The results showed that there were significant layer differences in temperature and salinity during the low-oxygen period. In the seawater, the nutrient distribution in the death disaster zone of sea cucumbers and the non-disaster zone was similar, and DO had a strong positive correlation with dissolved inorganic nitrogen (DIN). In the sediment, significant regional differences existed in nutrient concentration, and the concentration of total phosphorus (TP) decreased significantly with the increase in DO content. The results showed that the sources and sinks of nitrogen and phosphorus nutrients were inconsistent in this zone, and migration and transformation of the existing form of nitrogen with the seasonal changes in the water environment was a main factor for N distribution. This study extended the understanding of the effects of seasonal low-oxygen on N and P.

Interaction of the Coupled Effects of Irrigation Mode and Nitrogen Fertilizer Format on Tomato Production

The production efficiency and quality of tomatoes is affected by the mode of irrigation and the nitrogen forms. This study explored the impacts of different irrigation regimes, nitrogen forms, and their coupled effects on tomato production. The various irrigation regimes were set at 50%FC~90%FC (W1), 60%FC~90%FC (W2), 70%FC~90%FC (W3), and 80%FC~90%FC (W4) Furthermore, the control (CK) group followed a conventional drip irrigation regime in the local area. Nitrogen forms in this study comprised urea-based fertilizer (urea N 32%, F1), nitrate-based fertilizer (calcium ammonium nitrate N 15%, F2), and ammonium-based fertilizer (ammonium sulfate N 21%, F3). Combining these two factors yielded 15 treatment groups. The experiment was conducted in a solar greenhouse, and the soil type was sandy loam soil. The research focused on observing the yield, quality, and water–fertilizer use efficiency of tomatoes under these 15 treatment groups. The results demonstrate that irrigation had a more significant impact on the yield and nutrient accumulation rate compared to the nitrogen forms. To comprehensively evaluate the yield, quality, and water–fertilizer use efficiency of tomatoes, a combination evaluation method was employed. W3F2 produced the highest yield, CKF2 achieved the highest comprehensive quality score, and W2F2 had the highest comprehensive water and fertilizer use efficiency score. Using the fuzzy Borda model, the evaluation information of the three dimensions was combined. W3F2 ranked first, suggesting the adoption of an irrigation control regime of 70%FC to 90%FC, along with the application of nitrate-based nitrogen fertilizer during the fruit set to the harvest stage. It presented the best performance of tomato yield, quality, and water–fertilizer use efficiency across multiple dimensions.

Transcriptional Expression of Nitrogen Metabolism Genes and Primary Metabolic Variations in Rice Affected by Different Water Status.

The era of climate change strongly requires higher efficiency of energies, such as light, water, nutrients, etc., during crop production. Rice is the world's greatest water-consuming plant, and, thus, water-saving practices such as alternative wetting and drying (AWD) are widely recommended worldwide. However the AWD still has concerns such as lower tillering, shallow rooting, and an unexpected water deficit. The AWD is a possibility to not only save water consumption but also utilize various nitrogen forms from the soil. The current study tried to investigate the transcriptional expression of genes in relation to the acquisition-transportation-assimilation process of nitrogen using qRT-PCR at the tillering and heading stages and to profile tissue-specific primary metabolites. We employed two water supply systems, continuous flooding (CF) and alternative wetting and drying (AWD), during rice growth (seeding to heading). The AWD system is effective at acquiring soil nitrate; however, nitrogen assimilation was predominant in the root during the shift from the vegetative to the reproductive stage. In addition, as a result of the greater amino acids in the shoot, the AWD was likely to rearrange amino acid pools to produce proteins in accordance with phase transition. Accordingly, it is suggested that the AWD 1) actively acquired nitrate from soil and 2) resulted in an abundance of amino acid pools, which are considered a rearrangement under limited N availability. Based on the current study, further steps are necessary to evaluate form-dependent N metabolism and root development under the AWD condition and a possible practice in the rice production system.

Влияние повторного освоения залежей на свойства почв в Красноярской лесостепи

The studies were conducted from 2020 to 2021 on paired objects of pure deposits that are in the weedy stage of succession, as well as arrays of developed deposits in the initial stage of their use in arable land. In the conditions of the Krasnoyarsk forest-steppe, an assessment of the indicators of potential and effective fertility of various types of soils of these paired objects was obtained. as well as the results of taking into account the productivity of phytomass and crop yields. The state of the soil-absorbing complex practically does not change during the development and initial use of various types of soil deposits. When deposits are involved in arable land, the nitrate form of nitrogen in the soil somewhat prevails over the ammonium form due to the potentially high fertility of highly humus soils of the Krasnoyarsk forest-steppe. The availability of mobile phosphates in soils is low, and the exchange of potassium is increased or high, especially in soils of heavy granulometric composition. . The spatial variation of physical and chemical properties is very low in the soils of all objects, and the nutrition elements are high, especially in developed soils. Keywords: DEPOSIT, DEVELOPMENT, SOIL, AGROCHEMICAL PROPERTIES, SOIL-ABSORBING COMPLEX, NUTRITION ELEMENTS, VARIATION

The Importance of Natural Antioxidants in Female Reproduction.

Oxidative stress (OS) has an important role in female reproduction, whether it is ovulation, endometrium decidualization, menstruation, oocyte fertilization, or development andimplantation of an embryo in the uterus. The menstrual cycle is regulated by the physiological concentration of reactive forms of oxygen and nitrogen as redox signal molecules, which trigger and regulate the length of individual phases of the menstrual cycle. It has been suggested that the decline in female fertility is modulated by pathological OS. The pathological excess of OS compared to antioxidants triggers many disorders of female reproduction which could lead to gynecological diseases and to infertility. Therefore, antioxidants are crucial for proper female reproductive function. They play a part in the metabolism of oocytes; in endometrium maturation via the activation of antioxidant signaling pathways Nrf2 and NF-κB; and in the hormonal regulation of vascular action. Antioxidants can directly scavenge radicals and act as a cofactor of highly valuable enzymes of cell differentiation and development, or enhance the activity of antioxidant enzymes. Compensation for low levels of antioxidants through their supplementation can improve fertility. This review considers the role of selected vitamins, flavonoids, peptides, and trace elements with antioxidant effects in female reproduction mechanisms.

ПРОСТРАНСТВЕННОЕ РАСПРЕДЕЛЕНИЕ И СЕЗОННАЯ ДИНАМИКА ГИДРОХИМИЧЕСКИХ УСЛОВИЙ В ВИСЛИНСКОМ ЗАЛИВЕ БАЛТИЙСКОГО МОРЯ В 2020–2022 гг.

To study current hydrochemical conditions in the Vistula Lagoon and the trend of their change under changing anthropogenic impact in 2020–2022 seasonal variability and spatial distribution of hydrochemical parameters (salinity, pH, dissolved oxygen, BOD5, mineral forms of phosphorus and nitrogen) were investigated. The water body is exposed to intense anthropogenic impact from the Kaliningrad agglomeration, the nature of which has undergone qualitative changes in recent years, therefore, a comparative analysis was carried out with the period 2007–2016, which preceded the launch of modern treatment facilities in Kaliningrad. The Vistula Lagoon is characterized by spatial variability of hydrological and hydrochemical conditions, which was considered for 4 different types of regions (eastern, near-Baltic, central and Primorskaya Bay). The impact of anthropogenic factors on the dynamics of hydrochemical conditions had the greatest impact on the eastern region and Primorskaya Bay. The eastern region of the lagoon accounts for the main inflow of nutrients from the catchment area (from the Pregola River), and since 2016 the wastewater outlet from Kaliningrad is located here. Compared to the period before 2016, in the eastern area a significant increase of BOD5, a decrease of dissolved oxygen concentrations, a multiple excess of nitrite and nitrate nitrogen in comparison with the all of the water area lagoon were recorded. In the Primorskaya Bay, where until 2016 low-purity wastewater was supplied from the city of Kaliningrad, in 2020–2022 pollution for most of the studied indicators (BOD5, phosphate phosphorus, ammonium nitrogen) decreased and corresponded to the average values for the water area. The near-Baltic and central regions are strongly affected by natural conditions (sea water inflows), where in 2020–2022, as in the previous period, lower concentrations of nutrients were observed due to the remoteness from the main sources of pollution. Despite the decrease in the intensity of local pollution in the Primorskaya Bay in 2020–2022, the concentrations of mineral forms of nutrients remained at high levels, providing intensive development of algae (including the growth of BOD5) and eutrophication of the Vistula Lagoon.

Late-season corn stalk nitrate measurements across the US Midwest from 2006 to 2018

The late-season Corn Stalk Nitrate Test (CSNT) is a well-known tool to help evaluate the after-the-fact performance of nitrogen management. The CSNT has the unique ability to distinguish between optimal and excessive corn nitrogen status, which makes it helpful for identifying the over-application of N so that farmers can adjust their future nitrogen decisions. This paper presents a multi-year and multi-location dataset of late-season corn stalk nitrate test measurements across the US Midwest from 2006 to 2018. The dataset consists of 32,025 corn stalk nitrate measurements from 10,675 corn fields. The nitrogen form, total N rate applied, US state, year of harvest, and climatic conditions are included for each corn field. When available, previous crop, manure source, tillage, and timing of N application are also informed. We provide a detailed description of the dataset to make it usable by the scientific community. Data are published through an R package and also available at the USDA National Agricultural Library Ag Data Commons repository and through an interactive website.

Nitrogen forms and concentration influence the impact of titanium dioxide nanoparticles on the biomass and antioxidant enzyme activities of Microcystis aeruginosa

Nanoparticles (NPs) are becoming more widely produced, used, and released into the aquatic environment. In aquatic ecosystems, these NPs affect different populations of photosynthesizing organisms, such as cyanobacteria. This study aimed to evaluate the effects of titanium dioxide (TiO2) NPs (48mgl-1) combined with low (0.04mM) and high (9mM) concentrations of urea and nitrate on Microcystis aeruginosa. Microcystins (MCs) production and release were monitored in the cyanobacterium. The results showed that high urea concentration (9mM) combined with TiO2 NPs inhibited growth, pigment, and malondialdehyde (MDA) content by 82%, 63%, and 47%, respectively. The treatment also increased the reactive oxygen species (ROS) and glutathione S-transferase (GST) activity by 40.7% and 67.7%, respectively. Similarly, low nitrate (0.04mM) combined with TiO2 NPs inhibited growth by 40.3% and GST activity by 36.3% but stimulated pigment production and ROS concentration in M. aeruginosa. These responses suggest that high urea combined with TiO2.NPs and high nitrate combined with TiO2 NPs induced oxidative stress in cyanobacteria. The peroxidase (POD) activity of M. aeruginosa decreased by 17.7% with increasing urea concentrations. Our findings suggest that TiO2 NPs combined with changing nutrient (urea and nitrate) concentrations may adversely affect cyanobacterial development and antioxidant defense enzymes.

Role of Mineral Nitrogen Nutrition in Fungal Plant Diseases of Cereal Crops

Conventional chemical crop protection with pesticides is increasingly seen as being critical, because of pesticide residues in food and the environment. Integrated alternative management strategies such as crop rotations and soil management might also involve the targeted use of certain mineral fertilizers with benefits for plant health. A key element required for healthy crops is nitrogen, which is applied at differing dosages in various chemical forms, all with distinct effects on crop physiology and plant growth. Here, we review classical and more recent evidence for the crop disease-protective effects of nitrogen and various chemical nitrogen forms. We conclude that simple general statements concerning disease-protective roles in agricultural environments remain elusive, although complex plant-soil microbial interaction networks are becoming increasingly understood. The health of modern varieties might be substantially improved by certain chemical nitrogen fertilizer forms, particularly when the disease-causing fungal species are known.

Modelling of the impact of climate change on the transformation of nitrogen forms in the soil and N2O emissions from the agroecosystems of Eastern Ukraine

The moisture-temperature regime influences the nitrogen status of the soil and the microbiological processes of the transformation of nitrogen forms. Therefore, we assumed that ongoing climate change may affect the emission of nitrous oxide N2O, which is formed in the course of the transformation of nitrogen forms in the soil and is one of the most aggressive greenhouse gases that determine the global warming potential. To test this hypothesis and make a quantitative assessment of the impact of climate change on the transformation of nitrogen forms in the soil and N2O emissions from the agroecosystem soils, we used a complex model of greenhouse gas emissions from an agroecosystem soil that we developed and the RCP4.5 climate change scenario. The research was performed for the chernozem soils of Eastern Ukraine, with winter wheat being the cultivated crop. ‘Dry’ and ‘wet’ years typical for the period of 2021–2050 were selected among climate conditions in accordance with the climate change scenario. A ‘dry’ year was considered to be a year with a precipitation of 60% or less of the long-term average, a ‘wet’ year was a year with a precipitation of 130% or more of the long-term average for the studied period. The level of ammonification during the growing season for both ‘dry’ and partially ‘wet’ years was mainly controlled by temperature. At the beginning of the period, at negative temperatures below –3 °C ammonification and nitrification almost stopped, and at temperatures above –2 °C they slightly increased. Indices for the intensity of these processes increased with a rise in temperature from 0 °C to 10–11 °C. In the conditions of a ‘dry’ year an increment in temperature to the level of 22.4–27.8 °C caused a sharp increase in the rate of ammonification and caused a high level of the rate of nitrification. For the conditions of a ‘wet’ year with a sufficiently low (compared to a ‘dry’ year) temperature regime, a relatively significant rise in temperature with still quite good humidification increased the intensity of the ammonification process. The dependence of the intensity of the ammonification and nitrification processes on the moisture reserves in the soil is traced. The high level of moisture reserves in the arable layer at the beginning of the growing season in both ‘dry’ and ‘wet’ years formed anaerobic conditions in the upper layer of the soil. Against the background of rising temperatures, this called forth the denitrification process. N2O emission was 0.03–0.29 g N-N2O/ha•day due to the denitrification process in a ‘dry’ year, and 0.7–5.2 g N-N2O/ha•day in a ‘wet’ year. The highest level of N2O emission due to nitrification was observed in a ‘dry’ year in the middle of the vegetation period at high temperatures (22.7–27.8 °С) and amounted to 8.2–11.2 g N-N2O/ha•day. A decrease in soil moisture reserves during the second half of the growing season reduced the level of N2O emissions. Nitrification was the main process producing N2O. The emissions of N2O with moisture reserves greater than 55 mm in the arable layer occurred due to denitrification. A rise in temperature increases the level of N2O emissions. The peculiarities of the influence of moisture and temperature conditions of ‘dry’ and ‘wet’ years on the processes of ammonification, nitrification, denitrification, and N2O emissions from chernozem soils according to the RCP4.5 climate change scenario in Eastern Ukraine were assessed.