Variants Of Fertilization Research Articles

Energy Efficiency of Oat:Pea Intercrops Affected by Sowing Ratio and Nitrogen Fertilization

This study analyzed energy input (direct and indirect), energy output, net-energy output, energy use efficiency, energy intensity, and the energy productivity of oat:pea intercrops as affected by sowing ratio (oat:pea (%:%): 100:0, 75:25, 50:50, 25:75, 0:100) and nitrogen (N) fertilization (0, 60, 120 kg N ha−1). The two year field experiment was conducted on a calcaric Chernozem soil in the north-western part of the Pannonian Basin. The results for grain yield showed that pure stands of oat and pea had a higher energy use efficiency and energy intensity than intercrops, indicating that pure stands used the growing factors more efficiently than intercrops. The energy use efficiency was higher in pure pea than pure oat. The energy productivity for the above-ground biomass production was much more affected by the factor N fertilization than by the factor sowing ratio. The highest energy productivity of grain N yield and above-ground biomass N yield was achieved in pure pea stands (0:100). N in plant residues of the zero N fertilization variant required 68% lower technical energy than N from mineral fertilizer. The sowing rate of the intercrops is a management tool to trade-off between the benefits of the in-field biodiversity and energy efficiency.

INFLUENCE OF LEAF AND RADICULAR FERTILIZATION ON APPLE GROWTH AND FRUITING PROCESSES

Fertilization is a basic condition of agriculture, as a branch of sustainable development. It is often recommended to supplement mineral nutrition with organic product administration because, through their bio-stimulating effect, it potentiates mineral nutrition. Under these conditions, between 2020 and 2022, a bifactorial study was carried out on three apple cultivars (5-7 years after planting), grown at the Research Institute for Fruit Growing Pitesti-Maracineni, in a high-density orchard. The influence of five foliar and one soil fertilizers, on the background of standard mineral fertilization, over the mineral elements and chlorophyll content of the foliar apparatus for 'Red Braeburn', 'Jonagold Boerekamp', and 'Jonagold Novajo' cvs. was studied. Indicators of growth, fruiting processes, and fruit quality were also assessed. The foliar diagnosis results indicated that the level of mineral elements (N, P, Ca, Mg, Zn, Cu, and Fe) was within the limits of normality established for apple leaves, except for manganese, which accumulated in slightly excess (108.8, compared to 100.0 ppm). On average, during the experiment, the fertilization variants significantly increased the foliar level of mineral elements such as K, Cu, and Fe, compared to the control. Regarding the growth-fruiting processes, the mean of the tree trunk cross-sectional area annual growth was 6.6 cm2. Given that the percentage of fruit set fluctuated around 66.9%, a fruit yield of 66.8 t/ha was obtained. On average, the percentage of fruit set increased significantly by 16.9-19.5% when CropMax (0.2%), M1 (0.5%), and M2 (0.5%) products were applied, and fruit yield by 19.3-21.2% for Poly-Feed (1%) and Fertisol (2 kg/tree). The fruit weight ranged from 72.3 to 443.2 g, with an average of 166.5 g. The average values recorded for firmness, juice pH and total soluble content were 76.4 units HPE-II- FFF Bareiss, 3.6, and 12.7°Brix respectively. All fertilization treatments significantly increased the average weight of the fruit, by 6.2-9.2%, compared to the untreated variant. The results of the study certify the favorable effect of supplementing the fertilization plans with the studied products, containing biostimulators that enhance and harmonize the physiological processes of the apple in a high-density system.

Effect of Fertilization with Meat and Bone Meal on the Production of Biofuel Obtained from Corn Grain

The large volumes of meat and bone meal (MBM) being produced are leading to an increased demand for research into innovative methods of utilizing MBM and obtaining further benefits. The object of this study is to analyze the efficiency of bioethanol and biodiesel production obtained from corn grain fertilized with meat and bone meal produced from animal waste. For the realization of this study, a four-year field experiment was carried out with grain corn fertilized with different doses of meat and bone meal in comparison to fertilization with mineral fertilizers and no fertilization. Fertilization with meat and bone meal should be considered not only for its direct effect but also for the after-effect. The effect of meat and bone meals on obtaining a grain yield higher than that obtained on objects without fertilization and those fertilized with mineral fertilizers was noticeable after applying higher doses from the third year of the study. Fertilization with meat and bone meals did not significantly affect the average fat content of grain, and it only slightly affected the starch content. The positive effect of meat and bone meals on the yield of bioethanol from grain extracted from one hectare was responsible for their yield-forming effect. The differences obtained between years and between fertilizer variants in the yields of ethyl biodiesel and methyl biodiesel per one hectare were mainly related to grain yields, rather than the obtained volume per 1 kg from grain.

POTATO AND SUGAR BEET TECHNOLOGICAL QUALITY AS RESULTS OF DIFFERENT FERTILIZATION

In the agro-climatic conditions from Brasov area in the years 2014-2015, within the National Institute of Research and Development for Potato and Sugar Beet Brasov, were studied variants with NPK complex fertilizers applied for basic fertilization for potato crop by broadcast after furrow and at soil preparation before sowing at sugar beet crop. The basic fertilization was supplimented on all variants with a second fertilization with different forms of nitrogen. These fertilization technologies are adapted to the cultivation conditions in order to reach the maximum production potential in terms of quantity and quality and with guaranteed profitability for the two crops. In the case of sugar beet, the production on fertilization variants was analyzed qualitatively, the sugar content being strongly influenced by the fertilizer combinations used. Analyzing the technological quality of the potato, it was found a starch content decreasing in all fertilization variants.

Генетичне різноманіття зразків ячменю ярого за цінними господарськими ознаками

Goal. To determine the peculiarities of the formation of grain yield and elements of the crop structure depending on varietal characteristics, fertilization, and seed inoculation of common bean. Methods. Field — for recording grain yield, laboratory — for determining the main elements of the crop structure of common bean plants, statistical — for mathematical processing yield data by the method of dispersion analysis. Results. The factor that had the greatest influence on the main structural elements of the common bean crop was the variety. The lowest individual productivity in the experiment was characterized by the variety Halaktika. It should be noted the significant advantage of the Otrada and Nata varieties in terms of indicators of the structural elements of the harvest compared to other varieties. Thus, the number of beans per plant and the number of grains from 1 plant were greater in the variety Nata; these indicators were the maximum when applying potassium humate on the background of seed treatment with biological preparations: beans — 9.2 pcs. on a plant, grains — 35.9 pcs. from 1 plant. The determined indicators were higher than that ones of beans of the variety Bukovynka in the corresponding version of fertilizing by 0.6 pcs. and 5.8 pcs. from a plant. The mass of grain from 1 plant of the variety Nata was greater compared to the mass of the variety Bukovynka by 1.3 g/plant. The variety Otrada was especially distinguished by the number of beans, which were 10.4 pcs. on 1 plant. This variety provided the maximum weight of seeds per 1 plant — 8 g for the use of potassium humate on the background of seed treatment with biological preparations and application of N32P32K32. In this variant of fertilization, the maximum grain yield was formed by the varieties Ros, Nata, and Orada — 2.32; 2.41, and 2.45 t/ha, respectively. This exceeded the control variant by 0.29; 0.38 and 0.42 t/ha, respectively. Conclusions. Ros, Nata, and Otrada varieties provided the maximum indicators of crop structure and grain yield on average for 2018 – 2021. To fully realize the productivity potential, these varieties should be grown with the pre-sowing treatment of seeds with biological preparations and foliar fertilizing of crops with potassium humate on the background of N32P32K32 application.

Application of bacterial agents on sunflower

The study was aimed to examine the effects of bacterial agents combined with two variants of mineral fertilization on the sunflower yield.
 Materials and methods. The main field experiments were carried out in Department of Plant Production and Variety Investigations of the Plant Production Institute named after V.Ya. Yuriev of NAAS of Ukraine in 2016−2018.
 The soil was deep granular slightly leached chernozem. It had the following agrochemical parameters: humus content (Tyurin’s method) 5.8%; pH 5.8; hydrolytic acidity 3.29 mg/eq per 100 g of soil. The nutrient reserves in the control (no fertilizer): nitrogen – 132 mg/kg; phosphorus – 104 mg/kg; potassium – 128 mg/kg. The nutrient amounts with mineral fertilizer (N30P30K30): nitrogen – 130-140 mg/kg; phosphorus – 180−200 mg/kg; potassium – 170−190 mg/kg of soil.
 Data were statistically processed by variance and correlation analyses.
 Results and discussion. In2016-2018, sunflower plants grew and developed under very contrasting weather conditions compared to the multi-year averages. There was a water deficit during the critical periods (anthesis, seed setting and filling), especially at elevated air temperatures.
 In the study, biofertilizer GroundFix + bacterial agent HelpRost turned out to be the most effective combination. When GroundFix was used at a dose of 5 L/ha without fertilizer, the yield increased by 0.33 t/ha compared to the control; when it was used with N30P30K30 as basic fertilizer, the gain in the yield amounted to 0.36 t/ha. When the ‘GroundFix 5 L/ha + HelpRost’ combination was applied, the gain was 0.30 and 0.32 t/ha, respectively. The efficiency of HelpRost 3 L/ha in the “5−6 leaf pair” phase of the crop was -0.03 and -0.04 t/ha on the respective mineral fertilization. When the biofertilizer dose was increased to 8 L/ha, the yield was raised by 0.32 and 0.30 t/ha, respectively; when the increased dose was co-applied with HelpRost, the increment was 0.42 and 0.58 t/ha, respectively.
 There was a strong positive effect of April temperatures on the yield, with correlation coefficient of 0.36− 0.72, and of June temperatures (r = 0.33−0.59), except for the ‘GroundFix 5 L/ha + HelpRost 3 L/ha’ combination on basic fertilization with N30P30K30 (r = - 0.25 and r = - 0.07, respectively).
 Conclusions. When GroundFix was used at a dose of 5 L/ha without fertilizer, the yield increment was 0.33 t/ha compared to the control; when GroundFix was used at the same dose with N30P30K30, the increment amounted to 0.36 t/ha. By combining GroundFix 5 L/ha with HelpRost, we obtained the yield increments of 0.30 and 0.32 t/ha, respectively. Increasing the biofertilizer dose to 8 L/ha gave the yield gain of 0.32 and 0.30 t/ha, respectively. When the increased dose was co-applied with HelpRost, the gain was 0.42 and 0.58 t/ha, respectively.
 There was a positive correlation (r = 0.37−1.00) between the yield and precipitation amount during the growing period. We noted a strong positive effect of April temperatures, with correlation coefficient of 0.36−0.72, and of June temperatures (r = 0.33−0.59). 

Spring triticale productivity at different doses of nitrogen fertilizers

Mineral nutrition improvement contributed signifcantly to spring triticale grain yield. On average, during the two years of research, the use of 30–210 kg/ha of active ingredient of nitrogen fertilizers increased it to 6.50–8.36 t/ha or by 14–46 % compared to unfertilized plots (5.71 t/ha). The stability index of yield formation was high – 0.92–0.95. Weather conditions in research years were different. The precipitation level in April – June 2014 made 442.7 mm, and in 2015 – 87.5 mm. In 2014, the application of N30–210 signifcantly increased the grain yield – by 0.81–2.66 t/ha, and in 2015 – by 0.77–2.64 t/ha compared to no fertilizer variant. It is worth noting that the use of phosphorus–potassium fertilizers provided 0.30–0.32 t/ha. The application of 30–210 kg/ha of active ingredient of nitrogen fertilizers increased the protein content in spring triticale grain. During the two years of research, it increased, on average, from 13.7% in no fertilizer variant to 13.8–15.4 % or 1–12 %. The use of phosphorus– potassium fertilizers did not change this indicator. The use of high doses of nitrogen fertilizers (120–210 kg/ha) slightly reduced the stability index of protein content in the grain to 0.87–0.90. In terms of protein yield in triticale grain yield, variants with nitrogen fertilizers have signifcant advantage of unfertilized plots with the stability index of 0.92– 0.99. On average, during the two years of research, this indicator increased by 115–506 kg/ha or 1.1–1.6 times (894–1285 kg/ha) compared to no fertilizer variant. The use of phosphorus–potassium fertilizers increased protein yield to 818 kg/ha or 5 %. Gluten content varied greatly from the use of nitrogen fertilizers. On average, over two years of research, its content increased from 18.7% in no fertilizer variant to 20.4–26.4 % or 9–41 %. Stability index in this fertilizer scenario increased from 0.76 to 0.91. The use of phosphorus–potassium fertilizers had the least effect on gluten content – 19.3 %. In the conditions of the Right–Bank Forest–Steppe in the fertilizer system of spring triticale varieties of Kharkiv Khlibodar type the dose of nitrogen fertilizers is 60–90 kg/ha. In this scenario, the yield is 6.80–7.90 t/ha, protein content – 14.0–14.5 %, gluten content – 23.6– 25.0 %. The grain corresponds to the frst quality class according to SSTU 4762: 2007. Triticale. Specifcations. Key words: spring triticale, yield, protein content, protein yield, gluten content, nitrogen fertilizers.

Infestation of soft spring wheat by leaf diseases depending on nitrogen nutrition

Infestation of soft spring wheat plants depends on the growth stage and weather conditions of the growing season. Plants have the highest resistance to brown rust in the tillering stage. Brown rust developed in 2014 throughout the growing season. The lowest infestation intensity was during tillering – booting stage, which did not change from the experiment variant – 5.0 %. The lowest spread of brown rust was in the tillering stage – 10 %, in the booting stage – 40 %. The resistance was assessed 8 points. In the earing stage, the infestation intensity increased in no fertilizer variants and P30K30 to 8.0–8.2 % or by 60 % with a resistance of 7 points. This indicator in the variants with nitrogen fertilizers was 4.1–4.3 % with a resistance of 8 points, but all stems were infected (100 % spread). Affected leaves were in the middle layer, as their resistance by E. E. Saari and J. M. Prescott scale was at 5 points. Plants had the least resistance to brown rust in the milk stage of soft spring wheat grain. The intensity increased to 15.2–18.7 % or 2.1–4.7 times compared to the earing stage. The lowest resistance was assessed 6 points. All leaves were affected (resistance by E. E. Saari and J. M. Prescott scale – 1 point). In 2015, brown rust appeared in the milk stage of soft spring wheat grain. However, the infestation intensity was insignifcant – 5.0–6.5 % depending on the experiment variant. The prevalence of brown rust decreased from 60 % in unfertilized areas to 30 % on phosphorus–potassium background and up to 10 % with nitrogen fertilizers. Plant resistance was high – 7–8 points depending on the experiment variant. Powdery mildew develops throughout the growing season of both research years. In 2014, the infestation intensity is the lowest in the tillering stage – 7.7–8.0 % with 50 % spread, with the resistance of 7 points. In the booting stage of plants, the infestation intensity increased to 44.1–46.8 % or 5.8–5.9 times compared to the tillering stage. All plants were affected, and the resistance was 3 points. In subsequent stages of growth, the intensity of powdery mildew increased. Thus, in the earing stage this indicator increased to 65.1–69.2 % or 8.5–8.7 times, and in the milk stage – 9.5–9.7 times compared to tillering depending on the fertilizer. The stems of soft spring wheat were all affected, and the resistance was 2 points. Key words: brown leaf rust, powdery mildew, infestation intensity, spread, resistance.

Sorghum grain yield and energy efciency under different crop care measures

The results of research on the peculiarities of grain sorghum yield formation and its energy efciency depending on the use of microfertilizers and plant growth regulators in conditions of unstable moisture in the right-bank Forest-Steppe are shown in the article. The aim of the research was to identify the influence of elements of the technology of growing early-ripening grain sorghum hybrids on the productivity and energy efciency of the crop. During 2019–2021, research was conducted in the research feld of the training and production center of Bila Tserkva National Agrarian University. It was found that the most favorable conditions for the realization of the biological potential of the culture were in 2021, when the average experiment was 9.89 t/ha, compared to 2020 – 5.39 t/ha. It was found out that the best grain yields in the cultivation of Brigga sorghum hybrid were obtained with the use of foliar fertilizer with micro-fertilizer Alpha-Grow-Extra combined with Stimpo growth regulator – 7.71 t/ha. However, for the cultivation of Yutami sorghum hybrid, on the variant of application of foliar fertilizer with alpha-Grow-Extra microfertilizer, in combination with both growth regulators, the yield was 8.89 and 8.88 t/ha. It was determined that the best indicators of energy collection with grain in the cultivation of Brigga sorghum hybrid were obtained on the variant of foliar fertilization with microfertilizer Alpha-Grow-Extra, 2 l/ha in combination with Stimpo growth regulator – 116.72 GJ/ha. And for the cultivation of Yutami sorghum hybrid on the variant of application of foliar fertilizer with micro-fertilizer Alpha-Grow-Extra, in combination with both growth regulators, the minimum difference and maximum energy collection was obtained – 134.58 and 134.39 GJ/ha. Key words: grain sorghum, hybrid, growth regulator, microfertilizer, yield, energy efficiency.

Влияние различных комплексных удобрений на структуру урожая Zea mays L.

The main purpose of the research was to study the productivity of corn green mass and product quality indicators when using various norms of complex fertilizers in crops. Various variants of complex fertilizers were used. Based on the results of the research, fertilizer norms were determined, which contributed to an increase in yield from 8.6 cwt to 15.6 cwt, i. e. from 15.3% to 27.8%. Grain productivity was noted on the variants of applying complex fertilizers at a dose of 120 kg/ha, the yield of green mass is higher on the variants of applying both fertilizers at a dose of 140-160 kg/ha. These studies need to be continued.

Effect of Silicon-Containing Fertilizers on the Nutritional Value of Grass–Legume Mixtures on Temporary Grasslands

The study was conducted to evaluate the influence of silicon application on the botanical composition of grass–legume mixtures as well as the nutritional value of individual species and mixtures. The two-factor field experiment was established in a split-block arrangement. The two grass–legume mixtures, consisting of Dactylis glomerata, Festulolium braunii and Trifolium pratense or Medicago x varia and grass mixture—Dactylis glomerata, Festulolium braunii and Lolium perenne, were sown on arable land. Silicon foliar and mineral NPK fertilization was applied in three variants: NPK (non-Si-fertilized), NPK+Si (Herbagreen), NPK+Si (Optysil). Changes in the botanical composition in the sward of mixtures during the study period were influenced by the competitiveness of individual plants and weather conditions, whereas the effect of foliar fertilization with silicon was only slightly marked. The nutritional value of individual species of grasses and legumes varied over the years and also depended on the application of silicon. The greatest content of crude protein (CP), irrespective of the species and variant of silicon fertilization, was noticed in years with no drought. Our research confirmed the beneficial effect of silicon fertilization, independent of weather conditions, on the CP content and on the reduction of crude fibre (CF), neutral detergent fibre (NDF) and acid detergent fibre (ADF) in plants, especially when Herbagreen was applied. The nutritional value of the mixtures under applied silicon fertilization depended on botanical composition. In the conditions of low rainfall, a large share of F. braunii and an approximately 20% contribution of T. pratense resulted in a higher content of CP. These results may be used in the fertilization practices of temporary grassland for enhancing nutritional value, especially crude protein content, and on the reduction of fibre in the sward.

Трансформація гумусових речовин дерново-підзолистого ґрунту за тривалого внесення добрив

The article reflects the results of a study of the regularities of the transformation of humic substances at different levels of structural organization during long-term fertilization against the background of liming of podzolic sandy loamy soil in a field experiment in Western Polissya of Ukraine. It was found that the low content of chemically active organic substances in the humus composition of podzolic soils, caused by the zonal features of humus formation, can be positively corrected by applying fertilizers. Long-term use of organic and mineral fertilizers intensifies the process of new formation of humic acids and the formation of their mobile forms – the ratio of Cha-1 / Cfa-1 is 0.28 in the control without fertilizers and 0.33–0.88 in the variants of fertilization against the background of liming. With an organo-mineral fertilizer system, the most favorable conditions are formed for the humification of organic substances however, the type of humus remained fulvate – the Cha / Cfa ratio is 0.93 in the control variant and 0.41 – against the background of liming. Also, the application of fertilizers had an effect on the redistribution of the polydispersity of humic acids, which was characterized by a decrease in the heterogeneity of the composition of hydrophobic molecular aggregates. In a wide range of 1800 cm-1 to 2500 cm-1, a change in the direction of the line of the integral spectrum of soil humic acids under the application of CaCO3 from left to right was found, which is associated with a change in molecular parameters. Based on the results of chromatographic analysis, it was established that the profiles of the molecular distribution of humic acids podzolic soil correspond to the humus substances class. The first fraction is characterized by the formation of ion associates of larger molecules of polar composition. The recovery of humic acids occurred mainly due to high-molecular structures, which is the most sensitive to the application of fertilizers.

Съдържание и износ на основни макроелементи с биомасата и зърното на ечемик (Hordeum Vulgare L.) отглеждан като последействие

A field study with spring barley (Hordeum vulgare L.) was conducted on the area of long-term balance experiment in Tsalapitsa village near Plovdiv (Bulgaria), on alluvial-meadow soil. Mineral fertilization was not applied to this crop in order to equalize the area regarding nutrient content. The crop grown before barley was maize with 4 variants of fertilization and one control variant: N0P0, N100Р50, N150Р100, N200Р150, and N250P200. The present study aimed to evaluate the productivity, content and uptake of macronutrients (N, P, K, Ca and Mg) with the biomass of barley, grown as aftereffect. Due to the fertilization of the previous crop, different residual amounts of nutrients in soil lead to significant variability in barley yields. The highest grain yield was obtained in variant N250P200 - 3978.8 kg/ha, approximately four times higher than the yield in the control. Nitrogen content in the grain of barley is also influenced by the variants, being the lowest in the control - 1.25%, and the highest in variants N250P200 and N200P150 - 2.13% and 2.09%, respectively. The variability of P, K, Ca and Mg contents by variants is lower. With the total biomass of barley, depending on the variants of the experiment, between 23.2 - 132.7 kg N/ha; 26.6 - 146.3 kg K/ha and 9.3 - 36.5 kg P/ha were exported from the field. A good regression relationship was found between barley grain yield and nitrogen export with the total biomass (R2 = 0.859, P≤0.001).

ВПЛИВ СИСТЕМ ОБРОБІТКУ ГРУНТУ ТА УДОБРЕННЯ ІЗ ВИКОРИСТАННЯМ ПОБІЧНОЇ ПРОДУКЦІЇ НА ПРОДУКТИВНІСТЬ ПШЕНИЦІ ОЗИМОЇ В ЗАХІДНОМУ ПОЛІССІ УКРАЇНИ

The peculiarities of influence of tillage and fertilization systems with use of by-products on the winter wheat productivity were established by research, which was conducted on dark gray podzolic soil the in a four-field short-term crop rotation (winter rape - winter wheat – maize – spring barley). We studied three tillage systems (nonmoldboard plowing to 20–22 cm, shallow tillage to 10–12 cm, and surface tillage to 6–8 cm) and fertilization system with the use of crop by-products on the background of mineral fertilizers N128P90K120 kg/ha of crop rotation area. The highest plant productivity was formed by moldboard plowing to 20–22 cm and shallow tillage to 10–12 cm in fertilization variants with straw and straw + Ecostern destructor, in this case, the thousand grain weight was 47.1 and 47.9 and 46.4 and 47.0 g, the of grain weight per spike – 2.1 and 2.2 and 1.9 and 2.0 g. And lowest plant productivity was under surface tillage to 6–8 cm and various fertilization systems, where the thousand grain weight was 45.2–45.6 g, and the grain weight per spike 1.8–1.9 g. At moldboard and non-moldboard plowing to 10–12 cm and using straw + destructor, it was observed that an gluten content in winter wheat grain increased to 23.5 and 22.7 %, and protein content – to 12.9–11.7 % compared to with surface tillage, where these figures were 21.5 and 9.5 %, respectively. It was found that the moldboard plowing to 20–22 cm and shallow tillage to 10–12 cm was effective at winter wheat cultivation, which formed a higher grain yield – 6.80 and 6.32 t/ha. It was clarified that surface tillage to 6–8 cm caused a decrease in grain yield by 1.45 t/ha compared to the moldboard plowing. On average, over the research years, there was an increase in yield by 0.36 and 0.45 t/ha due to the use of straw as a fertilizer separately and in combination with the Ecostern destructor. By comparison, in the variant without straw, the yield was 5.89 t/ha on average by a factor. Consequently, we established that for winter wheat cultivation in the Western Polissia of Ukraine, it is expedient to carry out the moldboard plowing to 20–22 cm and the non-moldboard plowing to 10–12 cm and to use fertilization system with straw + Ecostern destructor + N 10 kg (ammonium nitrate) per 1 ton of straw. Key words: winter wheat, tillage, fertilizers, yield, destructor.

Effect of Organic Fertilization on the Physiological Status of Tomatoes under Abiotic Stress

Abstract During the vegetation period of the years 2020 and 2021 in the experimental field at Agricultural University - Plovdiv it was conducted a physiological study of tomato cultivar (Rugby) with determined growth under the treatment with chemical and organic fertilizers. The aims of the study were to determine the changes in physiological behaviour and productivity of field tomatoes depending on the fertilization and dates of planting. The physiological assessment included the measuring of some parameters of chlorophyll fluorescence and chlorophyll content index. Chlorophyll fluorescence has proved to have the potential to detect abiotic stress effects on photosynthetic efficiency. This technique was used to assess growth intensity in tomato plants (Solanum lycopersicum), grown in different types of fertilizer treatment and planted in three additional dates – 30.04, 07.05 and 14.05 in conditions of ambient heat stress. Results have shown the slight effect of the applied organic fertilizer upon fluorescence parameters but significantly improved chlorophyll content index compared to no treatment variant. Additionally, it was measured higher chlorophyll content index for the second and third planting dates. The highest average yield was calculated for the NPK variant, as the statistically significant differences of the yield between control and fertilization variants were calculated in 2021. It possessed the highest average yield for second planting compared to the third date of planting.

Mikrogranularno đubrivo i biostimulansi kao alternative diamonijum fosfatnom đubrivu za proizvodnju kukuruzana močvarnim zemljištima u severozapadnoj Nemačkoj

The eutrophication of groundwater through widespread diammonium phosphate (DAP) fertilization and excessive farm fertilizer is one of the major problems in European agriculture. Organomineral microgranular fertilizers that have a reduced phosphorus (P) content, alone or in combination with biostimulants, offer promising alternatives to DAP fertilization. We conducted a field experiment with maize (Zea mays) on a marshland soil site in order to compare the yield increase and the phosphorus balance of DAP and microgranular fertilizer variants. P content of the soil on the study site is 3.9 g P per 100 g soil. Treatments involved a combination of two fertilizers, namely DAP or a P-reduced microgranular slow-release organomineral fertilizer (Startec) and the biostimulants mycorrhiza, humic substances and soil bacteria, applied individually or along with two of the above biostimulants. Fertilizer variants were also tested individually without additional biostimulants. One in four plots was used as a control, treated only with biogas slurry, to identify site-specific spatial variability and to implement correction factors to process raw data using standardized methods. Startec performed as well as DAP in terms of both the yield and corn cob ratio, while the P excess was lower in plots treated with Startec (av. = 4.5 kg P2O5 ha-1 ) compared to DAP (av. = 43.7 kg P2O5 ha-1 ). The latter differences are of statistical significance. Individual biostimulants and a combination of multiple biostimulants rarely resulted in significantly higher yields, with the exception of some combinations with humic substances and mycorrhiza in individual years. The influence of the climatic conditions in each of the years was higher than the influence of the biostimulants. However, average increases in yield over three years would be economically beneficial for farmers in the case of the applied humic substances product and mycorrhiza. An adequate alternative to DAP was found in the form of a P-reduced microgranular fertilizer from Startec.

Effect of Cultivation Conditions on the Growing Activity of Winter Barley Genotypes

In the period 2018-2020 in the Institute of Agriculture - Karnobat, Bulgaria the influence of growing conditions on the growth activity of winter barley genotypes was studied. The experiments were performed in field and laboratory experiments. In a field multifactorial experiment with 4 fertilization variants (N0: N8: N12: N16) and three sowing rates (250, 350 and 450 germinating seeds) the barley varieties Kuber, Sayra, Zemela and Bozhin were grown. The obtained seeds from the different variants were studied in a laboratory experiment by the method of rolls. From each variant 20 seeds are laid in 3 repetitions on filter paper. The rolls are immersed in water and after 10 days the length of the first leaf, the length of the coleoptile, the number of roots and their length are taken into account. It was found that there are proven differences in the indicators in the studied genotypes. On average for the years of study, the length of the first leaf and the length of the roots is the largest for the seeds obtained in the variant at a sowing rate of 450 germinating seeds and N8. With the largest length of coleoptile and the largest number of roots are the seeds of the variant with a sowing rate of 250 germinating seeds and N8. Analysis of the variant shows that the length of the first leaf, the coleoptile and the number of roots depend on the genotype. The strongest influence on the length of the roots have the conditions of the year. The interaction between the two factors strongly influences all the studied indicators. The interaction between the year, genotype, sowing rate and fertilization also has a great influence on the indicators of the length of the first leaf, coleoptile and roots.

THE ZINC AGRONOMIC BIOFORTIFICATION AND ITS INFLUENCE ON WINTER WHEAT PRODUCTIVITY AND QUALITY

This study evaluates the influence of agronomic biofortification with zinc on the productivity and quality of winter wheat. The large number of people, globally, affected by the nutritional deficiency of minerals, requires urgent measures to remedy this shortcoming. Agronomic biofortification of zinc cereals is much faster than biofortification through breeding programs. The experiment took place at ARDS Lovrin and was placed in the field according to the randomized block method, in three repetitions. The three experimental factors - factor A - seed treatment, with the following graduations: a1 - without seed fertilization, a2 - with seed fertilization, factor B - variety: b1 - Ciprian variety, b2 - Glosa variety, b3 - Dacian variety and factor C - zinc treatment - c1 - unfertilized control, c2 - soil fertilization, c3 - foliar fertilization at the end of the tillering period, c4 - foliar fertilization in the heading phase, c5 - foliar fertilization in the milk phase, were study both unilaterally and in different combinations. It is noted, in the climatic conditions of the experimental period, as the fertilization variant to increase the zinc content in the grain, the variant with soil fertilization with zinc sulfate, when combined with seed treatment. In this combination, the highest values of zinc in the green plant, in the grain, the best production and quality results, statistical assurance for the probability of transgression of 5% and 1% respectively, are recorded. Regarding the formation of productivity elements - spike length, spike weight, number of spikelets in spike, number of grains in spike, weight of grains in spike - obvious correlations are established between them and the fertilization system approached. Thus, the number of spikelets in main spike correlates very significantly with the length of the spike (r = 0.73***), the number of grains in the spike correlates significantly with the length of the spike (r = 0.68**) and with the number of spikelets/ spike (r = 0.65**), the weight of the spike correlates very significantly with the number of grains / spike (r = 0.73***) and significantly different with the weight of the spike (r = 0.59**) and with the length of the spike (r = 0.57**).

Antioxidant Capacity and Nutritional Value of Potato Tubers (Solanum tuberosum L.) as a Dependence of Growing Conditions and Long-Term Storage

The aim of the study was to assess the interactive effect of the use of bio-fertilizer and organic matter brought into the soil, as well as to limit the use of mineral fertilization on the content of bioactive compounds in potato tubers cultivar ‘Satina’. The test results show a positive effect of the applied bio-fertilizer in all tested variants of organic fertilization (straw, fodder pea, manure) on the level of the tested compounds. Comparing the content of crude protein in tubers from plots where half the dose of mineral fertilization was applied, the use of bio-fertilizer increased the content of this component, especially after using straw. After 6 months of storage, organic fertilization had no significant effect on the protein content, while significant differences were found in tubers fertilized with mineral, in favor of the full dose of NPK fertilizers. The storage time increased the content of tyrosine, leucine, lysine, alanine, glutamic acid, and total AA, and also methionine, aspartic acid, and asparagine, while the content of isoleucine and phenyl-alanine decreased. The highest content of total polyphenols was found in tubers where the plots were covered with pea application, a full dose of mineral fertilizer, and the use of bio-fertilizer. Unfortunately, after 6 months of storage, potato tubers from plots fertilized with peas, especially those fertilized with half the dose of mineral fertilization and without the use of biofertilizer, significantly lost the most total polyphenols. Similar relationships were obtained for the level of chlorogenic acid in tubers, which is significantly correlated with the content of polyphenols, but only organic fertilization in the form of peas significantly increased the concentration of chlorogenic acid. On the other hand, the highest post-harvest antioxidant activity was characteristic of tubers from plots fertilized with manure, with a full dose of mineral fertilization and biofertilizer. During the 6-month storage, there was a decrease in the antioxidant capacity, on average 12.4% for the objects. This may indicate the influence of polyphenolic compounds as well as other antioxidants on the assessed trait.

The effect of an extended agricultural reclamation on changes in physical properties of technosols in post-lignite-mining areas: A case study from central Europe

Opencast mining destroys soils that have formed over many thousands of years. Their place is taken by post-mining areas such as external and internal dumps with materials whose physical and chemical properties are unfavorable from the point of view of plant growth and development. In order to minimize the negative effects of opencast mining, reclamation is necessary. In this work, we examined the impact of 42-year agricultural reclamation, in which three variants of mineral fertilization (0NPK, 1NPK, and 2NPK) were applied in the cultivation of alfalfa with the addition of orchard grass on changes in physical properties of Technosols. After forty-two years of agricultural reclamation, there has clearly been a differentiation of post-mining material into genetic horizons that differ in physical properties. The surface part of Technosols was converted to a humus-enriched surface horizon (Ap), which consisted of two subhorizons: Ap1 and Ap2, differing in structure, color, and consistency. In the 1978–2020 period in Ap1 of fertilized soils, there was a decrease in bulk density (BD, 9.0–10.9%) and particle density (PD, 1.5%), but an increase in structural stability index (SI, 243–337%), soil porosity (SP, 15.5–19.2%), air-filled porosity (AFP, 10.8–11.7%), field capacity (FC, 49–21.6%), plant available water capacity (PAWC, 46.4–48.0%) and S-index (46.9–50%). In the Ap2 subhorizon, there was a similar trend of changes; however, BD (for 2NPK), FC (for 1NPK), and PAWC (for 1NPK and 2NPK) were not significant. BD (5.4–14.3%) increased in most horizons of parent material (Cd) between 1978 and 2020, and SP (10.9–29%), AFP (16. 2–73.9%), and S-index values (9.4–34.4%) decreased. On the other hand, PD, SI, FC, and PAWC values did not change significantly.Cultivation o alfalfa with orchard grass in the 1978–2020 period significantly affected the profile variation in physical properties of Technosols, which was not observed when the field experiment was set up (1978). In the Ap horizon, DB and PD had significantly lower values, while SI, SP, AFP, FC, PAWC, and S had significantly higher values compared to parent materials (Cd). This is related to the indirect effect of soil organic carbon (SOC), which was beneficial to improving the surface horizon properties of developing Technosols. The diversity of physical properties of the 42-years old post-mining Technosols in the Ap was dependent on fertilization, especially in the Ap1 subhorizon. In fertilized Technosols, the BD and PD values were lower, and SP, DP, AFP, FC, PAWC, and S values were higher compared to unfertilized Technosols. Parent material (Cd) horizons after 42 years of reclamation had similar physical properties regardless of fertilization.