Levels Of Nitrogen Nutrition Research Articles

Влияние азотного питания на урожайность и аккумулирование нитратов отечественными и зарубежными сортами столовой свеклы в условиях Ленинградской области

The selection of varieties and the level of nitrogen nutrition are important technological elements that determine the yield and quality of table beets when grown on sod-podzolic soil. The article discusses the varietal response of table beet varieties to an increased level of nitrogen nutrition N180 and deficient N0. The varieties that accumulate the maximum and minimum amount of nitrates in different phases of growth and development, more effectively using soil nitrogen compounds or nitrogen fertilizers are identified. The varieties Golden Beet (9.12 kg/m2), Kholodostoykaya 12 (8.94 kg/m2) turned out to be more responsive than others to the application of an increased dose of nitrogen fertilizers, and the greatest increase in the yield of root crops to the background N0 was obtained in the varieties Kholodostoykaya 19, Tsilindra, Egyptian flat and PabloF1. Keywords: TABLE BEET, NITROGEN NUTRITION, VARIETIES, NITRATES, YIELD

Influence of mineral, organic, organomineral fertilization on winter hardiness components of columnar apple tree (<i>Malus domestica</i> Borkh.)

Intensive biological technologies of apple-tree cultivation with application of organic and mineral fertilizers form high nitrogen nutrition, thus leading to prolonged growth of fruit plants and reducing their winter hardiness. Columnar apple tree fail to demonstrate high potential for winter hardiness. Therefore, research into regularities and mechanisms behind the influence of nutritional status of columnar apple tree on indicators of plant winter hardiness is considered relevant. The research was aimed at establishing the influence of mineral, organic, organomineral fertilization on the components of winter hardiness of columnar apple trees grown on podzolic soil. Materials and methods. The research involved the ‘Triumph’, ‘President’, ‘Ostankino’ columnar apple varieties, as well as organic and mineral fertilizers. The experiment was conducted in 2016–2021 in the agrochemical experiment station of the Federal Horticultural Center for Breeding, Agrotechnology and Nursery (Moscow region) on podzolic soil of medium-loam particle size distribution. The experimental design included 4 variants: 1) control without fertilizers; 2) N90K90; 3) organic fertilizers 100 t/ha; 4) N90K90 organic fertilizers 100 t/ha. Naa (ammonium saltpeter), KCl mineral fertilizers were applied annually, organic fertilizer (horse manure with sawdust) was applied in 2014. Winter hardiness components and plant samples were analyzed according to generally accepted methods. According to the research into the influence of mineral, organic, organomineral fertilization on the components of winter hardiness of columnar apple tree (Malus domestica Borkh.) grown on podzolic soil in the conditions of the Moscow region, the fertilizer is found inefficient in terms of providing the optimal level of nitrogen nutrition of columnar apple tree plants, except for ‘Triumph’ variety when getting organic fertilizers at a dose of 100 t/ha. In January, fructose prevailed in the sugars of annual shoots of columnar apple tree plants. The ‘Triumph’ and ‘President’ varieties showed a tendency to increase in the content of fructose and glucose as compared with the control when getting organic fertilizers and their combination with mineral fertilizers. The same tendency was observed in the ‘Ostankino’ variety for the content of ascorbic acid in annual shoots, whereas this indicator of the ‘Triumph’ and ‘President’ varieties demonstrated the opposite trend. The ascorbic acid content in annual shoots in winter appeared consistent with its content in August shoots and remained independent on the content in leaves in August. With a decrease in temperature to -40 °C (component II of winter hardiness), the ‘Triumph ‘and ‘Ostankino’ varieties suffered reversible damage to the vegetative buds from 0 to 2.0 points, the ‘President’ variety introduced with 100 tons/ha organic fertilizers demonstrated an increase in damage to the vegetative buds to 3.17 points. The greatest damage to reproductive buds in the ‘President’ and ‘Ostankino’ varieties (3.85-3.91 on the control) was observed in component II of winter hardiness. The application of mineral and organic fertilizers increased these damages to complete death of reproductive buds. Injuries to bark, cambium in all variants of the studied varieties did not exceed 2.0 points. Wood appeared more damaged in the ‘Ostankino’ variety (up to 4.03 points in the combined application of N90K90 and 100 t/ha of organic fertilizers) as well as in the Triumph variety (up to 3.80 points in the N90K90 variant). As for component III of winter hardiness, an irreversible damage was noted for reproductive buds of the studied varieties in all variants of the experiment. In terms of component IV of winter hardiness, irreversible changes occurred in reproductive buds to the greatest extent (complete death in the ‘Triumph’ and ‘President’ varieties); in the tissue under reproductive buds, to the greatest extent in the ‘President’ variety (3.07 points in the variant of 100 tons/ha of organic fertilizers) and in the ‘Ostankino’ variety (2.76 points in N90K90), at the core, the maximum damage was noted in the N90K90 variant in the ‘Triumph’ (3.22 points) and ‘Ostankino’ (2.76 points) varieties.

Diagnosis of Cotton Nitrogen Nutrient Levels Using Ensemble MobileNetV2FC, ResNet101FC, and DenseNet121FC

Nitrogen plays a crucial role in cotton growth, making the precise diagnosis of its nutrition levels vital for the scientific and rational application of fertilizers. Addressing this need, our study introduced an EMRDFC-based diagnosis model specifically for cotton nitrogen nutrition levels. In our field experiments, cotton was subjected to five different nitrogen application rates. To enhance the diagnostic capabilities of our model, we employed ResNet101, MobileNetV2, and DenseNet121 as base models and integrated the CBAM (Convolutional Block Attention Module) into each to improve their ability to differentiate among various nitrogen levels. Additionally, the Focal loss function was introduced to address issues of data imbalance. The model’s effectiveness was further augmented by employing integration strategies such as relative majority voting, simple averaging, and weighted averaging. Our experimental results indicated significant accuracy improvements in the enhanced ResNet101, MobileNetV2, and DenseNet121 models by 2.3%, 2.91%, and 2.93%, respectively. Notably, the integration of these models consistently improved accuracy, with gains of 0.87% and 1.73% compared to the highest-performing single model, DenseNet121FC. The optimal ensemble model, which utilized the weighted average method, demonstrated superior learning and generalization capabilities. The proposed EMRDFC model shows great promise in precisely identifying cotton nitrogen status, offering critical insights into the diagnosis of crop nutrient status. This research contributes significantly to the field of agricultural technology by providing a reliable tool for nitrogen-level assessment in cotton cultivation.

PRODUCTIVITY OF WINTER CANOLA IN THE CONDITIONS FG “VROZHAYNE” OF VINNYTSIA OBLAST

The article provides measures to improve the intensive technology of growing winter rapeseed with a high level of adaptability for specific growing conditions when using a fertilizer system; the latest research and publications were elaborated; objectively assessed the importance and relevance of the study of the optimization of the main nutrients in order to achieve high performance indicators of winter rapeseed. The results of the study of the effect of different rates of mineral fertilizers on the formation of seed yield of the highly productive domestic winter rapeseed hybrid Hulk were analyzed. It has been established that mineral fertilizers are currently the basis for intensive technologies and play the most significant part in the cost structure of winter rapeseed cultivation technology. In today's difficult economic conditions, it is especially necessary to pay attention to the application of phosphorus fertilizers, because the provision of the soils of Ukraine with phosphorus fertilizers does not exceed 10% of their need, which poses a threat of soil degradation and a decrease in the productivity of agricultural crops. It has been established that winter rapeseed is particularly picky about the level of nitrogen nutrition. The highest efficiency is the application of nitrogen fertilizers to the soil in the form of KAS. Foliar feeding, effective only to eliminate nutrient deficiencies in the plant. The main method of providing plants with trace elements can be foliar feeding, which improves the availability of nutrients and reduces feeding costs. It is recommended to apply complex mineral fertilizers SUPERFOSFAT Makosh (P37Са62S60В0,4Zn0.4) + КАС64 in spring on frozen soil + microfertilizer AminoAlexin, at the rate of 1,0 l/ha in the stem formation phase + Vuksal Microplant 1,5 l/ha in the budding phase of winter rape, which will allow to obtain the yield of winter rape seeds at the level of 3,94 t/ha.

Nutrient Diagnostics and Biochemical Indicators of Oat Grain Quality Predicted by Leaf Juice Amino Acid Concentration

In order to find out the relationship between the level of nitrogen nutrition of oat plants of the Yakov variety and the content of amino acids in leaf juice, as well as the possibility of using this indicator to assess the content and composition of proteins, the activity of amylases, catalases and peroxidases in ripe grain and the activity of theseenzymes in germinating grain, a field experiment was carried out at the Field Experimental Station of Russian State Agrarian University – Moscow Timiryazev Agricultural Academy, on sod-podzolic medium loamy soil. In the field experiment, variants with different levels of nitrogen nutrition of oat plants that had passed post-harvest ripening were tudied. Ammonium nitrate, double superphosphate, and potassium chloride were applied in advance. As a result, it was found that as the level of nitrogen nutrition of plants increased, the concentration of amino acids in the juice of oat leaves at the stage of formation of the first stem node decreased, which was closely correlated with the nitrogen doses. These data indicate the possibility of using this indicator for the diagnosis of nitrogen nutrition in oat plants. The studies also revealed a reliable correlation between the content of amino acids in leaf juice and the concentration of proteins soluble in water and solutions of 10% KCl, 0.2% NaOH, as well as the activity of acid (pH 5.5), neutral (pH 7) and alkaline (pH 8) isoenzymes of α-amylase and acid isoforms of β-amylase in ripe grain. In addition, the amino acid content of leaf juice was found to be significantly correlated with the activity of acidic α-amylase, acidic and neutral β-amylase in germinated grain. The results obtained demonstrate the possibility of predicting the level of protein accumulation in oat grains. It is also possible to predict the protein composition, activity of α- and β-amylase, catalase, and peroxidase isoenzymes from the content of amino acids in leaf juice in the phase of the first stem node formation. A reliable correlation was also found for the activity of acid and neutral isoenzymes of α-amylase, catalase, and peroxidase in ripe and germinated oat grain.

Monitoring of grain crops nitrogen status from uav multispectral images coupled with deep learning approaches

Effective nitrogen nutrition is vital for better crop yield. In order to get the maximum yield from a field, nutrition must be spread evenly among all crops. Therefore, this paper proposes a combination of deep learning image segmentation methods to monitor nutrition across an agricultural field and detect areas with shortages of nutrients. In particular, the authors consider the applicability of five state-of-the-art neural network architectures based on U-Net to solve the nitrogen level rate segmentation problem for crops on an orthophotomap. Training, effectiveness assessment, and applicability of these neural network models are carried out by the authors on their own multi-datasets, collected by using UAS (Geoscan 401) at the Agrophysical Research Institute (ARI) experimental biopolygon for 2020–2021. The survey was performed using a MicaSense RedEdge-MX multispectral camera (5 channels in total). The total size of the collected dataset is more than 20 thousand images of two different agricultural fields (with a total area of about 62 ha). On each field, there are six test areas with known nitrogen nutrition levels (founded by agronomists). Images of these test areas are used for data augmentation and training of the above-mentioned neural network models (U-Net, Attention U-Net, R2-UNet, Attention R2-Unet, and U-Net3+). Also, in this research, an experiment was conducted to evaluate the influence of the choice of different bands of field images on the accuracy of the considered segmentation methods. The experiment showed that among all models, Attention R2U-Net (t2) proved to be more robust and reliable for different kinds of crops (accuracy 97.59–99.96%). The authors also evaluated the impact of using different combinations of image bands (such as RGB, RedEdge, NearIR, and NDVI) on the segmentation accuracy of the neural network model. The combination of RGB, NearIR, and NDVI channels allowed for the high values of all 8 metrics used in this research (0.41–1.77% more than the standard combination of RGB bands). The use of the RedEdge band has a significant negative impact on the quality of segmentation of the nitrogen level in the agricultural field. The proposed method based on Attention R2U-Net (t2) and a combination of RGB, NearIR, and NDVI bands is stable for different types of agricultural landscapes and can help to improve crop nutrition and yield.

Growth and development of seedlings of Robinia pseudoacacia (L.) for the production of planting material in conditions of chestnut soils south of the Russian Federation

Robinia (R. pseudoacacia) is distinguished by a high level of ecological plasticity and is able to grow in different agroforestry areas under conditions of chestnut soils in southern Russia. The research was carried out in cluster collection sites of the Federal Research Center of Agroecology of the Russian Academy of Sciences (Lower Volga Station) and on the basis of the Volgograd Forestry State Educational Institution according to generally accepted methods in 2022. The purpose of the research was to analyze the technological features of the dynamics of growth and development of seedlings of R. pseudoacacia, to conduct a bioinformatic analysis of the gene sequence and to assess the prospects of their use for the production of planting material. Physiological indicators for assessing the Robinia generic complex stability have been identified. The economically valuable signs identified were morphological characteristics to the method of the Federal Scientific Center of Agroecology of the Russian Academy of Sciences, features of nitrogen fixation and the pigment complex. All the studied seedlings of R. pseudoacacia were at a sufficient level of nitrogen nutrition. On the territory of the Lower Volga station, plants formed a larger growth and biomass with the largest number of nodules than Robinia seedlings on the territory of the Volgograd Forestry State Budgetary Institution. However, the mass of nodules on the roots decreased with an increase in the humus content of the experimental site in Kamyshin (0.93%), which was explained by favourable weather conditions for the development of this plant during the growing season of seedlings and a sufficient amount of nutrients for the formation of these nodules – nitrogen and its compounds. This plantation planting material Robinia pseudoacacia (L.) had the property of adapting to the type of soil, thereby being a potential breed for growing in protective plantings and landscaping plantings of various functional purposes on chestnut soils of Russian Federation.

Physiological Response of Nutrient-Stressed Lemna gibba to Pulse Colloidal Silver Treatment.

Wastewater is a source of many environmental pollutants and potentially high concentrations of essential plant nutrients. Site-specific nutrient levels may influence the response of exposed plants to a chemical stressor. In the present study, we focused on the responses of model aquatic macrophyte swollen duckweed (Lemna gibba L.) to a short pulse exposure and a commercially available colloidal silver product as a potential environmental chemical stressor, combined with two levels of total nitrogen and phosphorus nutrition. Treatment with the commercially available colloidal silver product caused oxidative stress in L. gibba plants under both high and low nutrient levels. Plants grown and treated under high nutrient levels showed lower levels of lipid peroxidation and hydrogen peroxide accumulation, as well as higher levels of photosynthetic pigment content in comparison to treated plants under low nutrient levels. Higher free radical scavenging activity for plants treated with silver in combination with high nutrient levels resulted in better overall protection from silver-induced oxidative stress. The results showed that external nutrient levels significantly affected the L. gibba plant's response to the colloidal silver presence in the environment and that nutrient levels should be considered in the assessment of potential environmental impact for contaminants.

Contribution of weather conditions and anthropogenic activity to the variation of grain yields in the North-West of Russia

Current trends in climate change associated with the growth of heat supply contribute to the growth of bioclimatic potential and the increase in productivity of grain crops in the North-West of Russia. In such conditions, research is relevant aimed at clarifying the contribution of weather conditions and anthropogenic activity in the formation of the crop. The research was conducted on the crops of winter rye, spring barley, winter wheat, and spring wheat of the experimental landfill of the Menkovsky branch of the Agrophysical Research Institute. We studied various factors of anthropogenic activity, such as the level of mineral or nitrogen nutrition, an integrated plant protection system, seeding rates, and the size of seed material. Variance analysis was used in statistical processing. According to the results obtained, weather conditions were the most significant factor of productivity for winter cereals, and mineral nutrition was crucial for spring crops. The integrated protection system was less important than both the weather conditions of the growing season and the background of mineral nutrition of cultivated plants. This factor appeared to be the least significant for winter rye, which often has a favorable phytosanitary situation. The novelty of the data obtained lies in determining the predominant value in varying the yield of nitrogen fertilizers and herbicide treatment for spring wheat. A little less critical were the seeding rate and the size of the seed material.

Comprehensive evaluation of Robinia Pseudoacacia L. seedlings in an irrigated nursery for use in forestry and gardening in the lower Volga region

The generic complex of Robinia is a fundamental and key component for urbanized and agroforestry zones. Robinia pseudoacacia L. is widely used in landscaping and protective forest plantations. Planting material has sufficient stability and durability. The studies were carried out in the nursery of the Nizhnevolzhskaya Station for tree species breeding (No. 34:36:0000:14:0178) by field stationary and laboratory methods using generally recognized methodological schemes for organizing work and constructing samples, statistical processing of primary information and analysis of variance were carried out according to generally accepted methods. The object was seedlings of the same age of Robinia pseudoacacia L. The purpose of the study was to substantiate the biometric characteristics of seedlings of Robinia pseudoacacia L. to assess the potential reclamation and decorative functions of plantations in the dry steppe conditions of the Lower Volga region. Physiological indicators of the breed have been established to determine the level of stability of the generic complex Robinia. The reaction of the pigment complex of robin plantations in the conditions of the Volgograd region was revealed. The stock of nodule bacteria Robinia pseudoacacia L at the end of the juvenile period was determined. Robinia plants are in optimal condition, actively carry out metabolic processes and protein synthesis and do not experience nitrogen deficiency (at the level of 18.4 ± 0.3), which indicates a sufficient level of nitrogen nutrition, active synthesis of metabolites, active growth and development plants. During the first year of vegetation, a specific reaction of Robinia was shown at the morpho-physiological level. Plants form a good growth, a high mass of roots and aerial mass, contribute to an active entry into symbiotic relationships with nitrogen-fixing bacteria, contain a sufficient amount of chlorophylls, flavonoids, xanthophylls. This plantation planting material of Robinia pseudoacacia L. of seed origin is recommended for creating highly productive protective plantings and plantings of greenery for various purposes in settlements and beyond in the Lower Volga region.

Effect of Nitrogen Nutrition and Planting Date on the Yield and Physicochemical Parameters of Flowering Chinese Cabbage

The nitrogen requirements of flowering Chinese cabbage are unknown. Our study aimed at investigating the effect of varied nitrogen nutrition levels (including 50, 70, 90, 110, and 130 mg N per dm3, described as N-50 to N-130, respectively) on the yield of flowering Chinese cabbage (Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee) grown in two varied soilless cultivation systems (substrate and hydroponic) and seasons (spring and autumn). We confirmed that the intensity of the nitrogen nutrition modified the yield of plants within a range of 50 to 90 mg N; the yields were increased; however, the higher N concentrations were not effective. In both cultivation systems, the content of K, Ca, and Fe in leaves was higher in autumn compared to spring. Nitrogen nutrition improved the weight of plants—an effect that varied depending on the system of cultivation—and increased the phenolic content. N-90 was the optimal level of nitrogen nutrition. More intensive N-nutrition did not significantly modify plant yields or phenolic content. We Concluded that N fertilisation might be an effective tool to obtain plants with high bioactive compound content.

Dependence of crop capacity and grain quality of winter triticale varieties on the level of mineral nutrition and seeding rates

Relevance and methodology. The response of present winter triticale varieties to the nitrogen nutrition level was assessed at different seeding rates in the agro-climatic conditions of the Bryansk region. The research object was a set of new winter triticale varieties cultivated by intensive technology on gray forest tame soils in the Bryansk region.The purpose of the research was to identify the potential of crop capacity and grain quality of present varieties of winter triticale, depending on the mineral nutrition level and seeding rates. Field experiments were carried out in the educational and experimental farm of the Bryansk State Agrarian University in 2019–2021 with the following crop rotation system: vetch-oats mixture for green fodder, winter triticale, potato, spring wheat.Results. It was established that the grain yield of the varieties under study largely depended on the conditions of moisture and heat availability in the growing season. In the experiment variant with N168Р96К96 and additional fertilizing of ammonium nitrate and ammonium sulfate at the rates of N24 and N10 during spring vegetation and in the shooting stage, the varieties Tornado, Runo, Nina, Impulse, Tribune, Carnet and Legion were distinguished due to the producing programmed grain yield — from 85 to 100 ctw/ha. The grain yield of the varieties Dynamo, Nemchinovskaya 56, Promet and Valentin was from 83.3 to 84.4 ctw/ha on average. In the experiment years all the varieties under study formed stable yields and grain with a high content of crude protein and gluten. On tame soils, with high rates of mineral fertilizers and tank mix of herbicides, the seeding rates of winter triticale seeds can be reduced to 4.5 and 5.0 mln pcs of germinating seeds per 1 ha, therefore, these agrotechnical techniques can be recommended into production as the most important factor of increase of high-quality grain yield.

Photometric method of response to changes in potato varieties to nitrogen stress

Relevance. The use of non-invasive photometric methods for assessing the stress states of plants makes it possible to assess the physiological state and resistance of plants.Material and methods. In small-field and vegetation experiments, we studied the photometric indicators of the physiological response of potato varieties (reflection coefficients in different ranges) to nitrogen stress created by five doses of fertilizers using contact (N-tester) and remote (N-sensor) methods.Results. Potato varieties released for the conditions of the North-Western region of the Russian Federation were studied for their ability to withstand stress provided by low and high levels of nitrogen nutrition of plants and different weights of planting tubers. The resistance of plants of different genotypes to external and internal stressors was studied by the reflection coefficients measured in 4 channels, which characterized the differences in the physiological state of plants. Ensuring the potential genotypic resistance of the organism in the form of a decrease in FIS F1,3 corresponds to the inclusion of various mechanisms of plant adaptation to external or internal influences, depending on the genotype. In the vegetative experiment, of the studied photo-optical reflection coefficients, the most informative were the FIS F1,3 indicators, which showed that the overall viability of such varieties as Peterburgsky, Charodey and Kholmogorsky turned out to be increased. The reaction type of the Kholmogorsky variety is the most promising for growing plants under stress conditions.

The Effect of Various Foliar Treatments and Nitrogen Nutrition Levels on the Yield and Physicochemical Parameters of Flowering Chinese Cabbage

Flowering Chinese cabbage (Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee) is an original leafy vegetable from China, and it is a valuable source of bioactive compounds. In the literature, there are no practical recommendations for the cultivation and fertilization of this species. Our study aimed to investigate the effect of nitrogen nutrition levels (70 and 90 mg N per dm3) and various foliar treatments (Se, Si, Li, V, and SA—salicylic acid) on the quantity of the yield and the quality of flowering Chinese cabbage grown in two varied soilless cultivation systems: under pot cultivation (mixture of peat and sand) and hydroponic culture. In conducted studies, we have confirmed the hypothesis that the intensity of nitrogen nutrition and the application of foliar spraying modify the yield of plants, both the quantity and the quality aspects. The factors under analysis had a diversified and multidirectional influence on the yield, growth, and quality of the plants. The results varied between the two cultivation systems. This was proved by the PCA (principal component analysis). Generally, the plants grown in the hydroponic system were characterized by higher yields than those grown in pot cultivation. This was found to be a stimulating effect of N nutrition on the content of that nutrient in the aerial parts of the plants. Plants sprayed with Si and Se were characterized by a high content of Chl a, Chl b, carotenoids, and relatively high antioxidant activity. Finally, the samples subjected to different foliar spray treatments could be classified into appropriate groups based on the quality parameters.

Nitrogen and Boron Dosage Effects on Arginine Accumulation in Scots Pine Needles

Free arginine (Arg) content was observed to multiply when the level of nitrogen (N) nutrition was high, and additional fertilization with boron (B) potentiated this effect. Owing to this feature, conifers can be suggested for use as bioproducers of Arg. Concentrations of Arg in relation to N and B fertilization needed to be better understood. The effect of soil fertilization with N and B on accumulation of these elements and free Arg in one-year-old needles of 16-year-old Scots pine (Pinus sylvestris L.) trees was determined in this study. Plantations were fertilized with doses of N from 0 to 1000 kg ha−1 and B from 0 to 6 kg ha−1. Fertilization with 3 kg ha−1 B at N doses of 200–500 kg ha−1 stimulated the accumulation of N in needles of up to 3.1–3.6% dry weight (DW). The level of Arg in needles increased from 74.7 to 175.9 μmol g−1 DW at these levels of N and B.

Rapid determination of ammonia nitrogen concentration in biogas slurry based on NIR transmission spectroscopy with characteristic wavelength selection

As an important intermediate product of the anaerobic digestion (AD) process, ammonia nitrogen (AN) is an essential indicator for analyzing the nitrogen nutrition level in the biogas system. To realize rapid evaluation of ammonia nitrogen concentration (ANC) in biogas slurry during AD, a detection model of ANC was established by combining near infrared (NIR) transmission spectroscopy with partial least squares. The CARS-GSA was constructed based on the competitive adaptive reweighted sampling (CARS) algorithm combined with the genetic simulated annealing algorithm (GSA), which was applied to characteristic wavelength selection of AN for improving the accuracy and efficiency of the spectral detection model. Through the selection of wavelengths by CARS-GSA, the modeling wavelengths decreased to 47 from 1557 of raw spectra, and the performance of the ANC regression model was effectively improved. For the CARS-GSA model, the determination coefficient, root mean squared error and residual predictive deviation of the validation set were 0.989, 12.549 and 9.662, respectively. For the independent test set, the above indexes were 0.990, 21.341 and 9.821, and consistent with those of the calibration set. The results showed that CARS-GSA could effectively reduce modeling wavelength variables and enhance prediction ability of the model. This study provides a theoretical support for the application of NIR transmission spectroscopy in online detection of ANC in biogas slurry.

Formation of productivity and grain quality of spring barley varieties depending on the seeding rates and the level of nitrogen nutrition in the forest-steppe of the Altai Territory

Formation of productivity and grain quality of spring barley varieties depending on the seeding rates and the level of nitrogen nutrition in the forest-steppe of the Altai Territory

Morpho-physiological traits, antioxidant capacity and nutrient accumulation in hemp (Cannabis sativa L.) under varying levels of nitrogen nutrition

Optimization of nitrogen fertilizer application is an important means of improving hemp (Cannabis sativa L.) production and economic benefits with minimum environmental loss. The method of fertilization with hydroponic could precisely control the amount of nitrogen applied, to understand how nitrogen application can affect the growth and physiology of industrial hemp. A hydroponic experiment was conducted in 2017 to investigate the effects of different nitrogen treatments (0.30, 0.75, 1.50 and 12.00 mmol/L) on different regions and types, cultivars of hemp (“Wanma 1(WM1)”, “Bamahuoma (BM)’, “Ynuma 5 (YM5)” and “Yunma 7 (YM7)”). The main objective was to determine the effectiveness of nitrogen fertilizer application for improvement of the morpho-physiological traits, antioxidant capacity and nutrient accumulation of industrial hemp. In general, increasing N application rate positively impacts hemp total dry biomass, plant height and stem diameter. Total dry weight, stem diameter and plant height increased by 26.16%-238.94%, 11.43%-34.09% and 4.51%-54.73%, respectively, with the application of 1.50 mmol/L when comparing with the low N rate (0.30 mmol/L). Nitrogen deficiency leads to cell membrane lipid peroxidation (MDA) and increases in superoxide dismutase (SOD) activity. The activity of nitrate reductase (NR) in hemp leaves and the accumulation of nitrate nitrogen are related not only to the nitrogen supply but also to the form of nitrogen. In addition, increasing nitrogen supply has a significantly negative effect on the utilization efficiency of nitrogen and potassium, but positively on the phosphorus utilization efficiency. Nitrogen supply and cultivar proved to be relevant to the growth, physiology and nutrient accumulation in hemp under hydroponic conditions. Increasing nitrogen supply within a reasonable range is beneficial to hemp, whereas excessive nitrogen supply has an inhibitory effect, and the nutrient utilization efficiency significantly reduces.

Продуктивность лофанта тибетского (Agastache rugosa) в зависимости от агротехнических приемов возделывания в условиях интродукции на Среднем Урале

Abstract. Research on the introduction of lofant (Agastache rugosa) has been conducted by the Department of Crop Production and Breeding of the Ural State Agrarian University since 2013. Studied by sowing seeds in open ground, especially the growth and development of lofant Tibetan background on the various types of mineral fertilizers, the effect of physiologically active substances comparative assessment of the types and varieties of lofant. The research was carried out in the Uralets agricultural farm, located in the Beloyarskiy district of the Sverdlovsk region. Methods. Phenological and biometric observations of plant growth and development were carried out. The method for laying the experience is generally accepted according to B. A. Dospekhov. This article presents the results of the introduction work on the study of the seedling method of cultivation and application of increasing doses of nitrogen fertilizers, which had the most pronounced effect on productivity, as well as on the structural composition of aboveground biomass – the most important indicator of quality in the preparation of medicinal raw materials. Purpose of research. To identify the features of the formation of productivity of aboveground biomass of the Agastache rugosa in the natural and climatic conditions of the Middle Urals. The task was to study the influence of seedling cultivation method, as well as the introduction of increasing doses of nitrogen fertilizers on the productivity and structural composition of aboveground biomass of Agastache rugosa. Results. The study revealed a clear dependence of the productivity of Agastache rugosa on the time of sowing seeds for seedlings: the earlier the sowing period, the higher the productivity. The maximum yield of medicinal raw materials per unit area was obtained in the I variant (seeding on seedlings – March 10) – 25.2 t/ha, the minimum productivity was formed in the IV variant (seeding on seedlings – April 10), it was 16.2 t/ha, which is 35.7 % lower than in the I variant (on average for 2013–2015). It is established that the higher the level of nitrogen nutrition, the greater the biological productivity. The maximum productivity (on average for 2018–2020) was 29.5 t/ha (IV variant – N60 kg/ha). Scientific novelty. For the first time, in the conditions of the Middle Urals, the features of the formation of productivity of Agastache rugosa with the seedling method of cultivation and different levels of nitrogen fertilizers were determined. Established: the optimal time for sowing seeds for seedlings and the dose of nitrogen fertilizers, in which Agastache rugosa provides high productivity with an optimal structure of medicinal raw materials.

Nitrogen regime of haplic Luvisol in orchards at fertilization

The aim of the investigation was to research the mineral nitrogen (Nmin) behavior in loamy haplic Luvisols of orchards located in the forest-steppe zone of the Central Russian Upland. The seasonal dynamics of N min (ammonium + nitrates) was studied during the growing seasons of 2018 and 2019 in field experiments with apple and sour cherry. Fertilizers were applied annually in spring at doses increasing from N30K40 to N120K160. The most important factors influencing the nitrogen dynamics were meteorological conditions, productivity of trees, peculiarities of nitrogen uptake by the studied crops. Fertilization of orchards with nitrogen contributed to an increase in Nmin content by 1.5 … 5 times, depending on the dose. The dynamics of Nmin in the soil of fertilized and unfertilized plots was similar and depended on the biological features of the crops: the lowest indicator’s level in the soil under sour cherry was in July during fruit ripening, while in the apple orchard a low nitrogen content was noted in August. Studies have shown that in the climatic conditions of the Central Russian Uplands, loamy haplic Luvisols without additional application of nitrogen fertilizers can provide a favorable level of nitrogen nutrition for apple and sour cherry trees in the first years of fruiting.