Foil Tunnel Research Articles

CULTIVATIONS CONTROL SYSTEM IN A FOIL TUNNEL

The foil tunnel crop control system presented in this article operates an irrigation system and a system that regulates air temperature and humidity. The irrigation system consists of solenoid valves, supplying water to a tunnel area divided into four zones. This allows four different types of plants to be grown. The system uses rainwater, collected in a reservoir when it is available. The water is delivered to the plants via by means of rubber hoses with holes. Thanks to this solution, the water is fed directly under the plant. The executive elements of the control system temperature and humidity are a motor and a fan. The motor opens the window when the measured parameters exceed the set value. If the humidity of the air is too high the fan is switched on, accelerating the air exchange. The system has an anemometer, the purpose of which is to measure and report dangerously strong winds. When the wind speed exceeds a critical value, the microcontroller forces the windows to be closed to protect the tunnel. The system also has a display, showing values of measured parameters and setpoints, as well as buttons to view them and change the expected value. An alarm is attached to the system. It is activated when the microcontroller registers a parameter value that is impossible to achieve under the tunnel's operating conditions. This indicates a possible failure of the measuring system. The executed system correctly adjusts the indicated parameters within its tolerance. The system has confirmed its usefulness, effectively reducing the time and labour required for plant care.

Pre-Acclimation to Elevated Temperature Stabilizes the Activity of Photosystem I in Wheat Plants Exposed to an Episode of Severe Heat Stress.

The importance of high temperature as an environmental factor is growing in proportion to deepening global climate change. The study aims to evaluate the effects of long-term acclimation of plants to elevated temperature on the tolerance of their photosynthetic apparatus to heat stress. Three wheat (Triticum sp. L.) genotypes differing in leaf and photosynthetic traits were analyzed: Thesee, Roter Samtiger Kolbenweizen, and ANK 32A. The pot experiment was established in natural conditions outdoors (non-acclimated variant), from which a part of the plants was placed in foil tunnel with elevated temperature for 14 days (high temperature-acclimated variant). A severe heat stress screening experiment was induced by an exposition of the plans in a growth chamber with artificial light and air temperature up to 45 °C for ~12 h before the measurements. The measurements of leaf photosynthetic CO2 assimilation, stomatal conductance, and rapid kinetics of chlorophyll a fluorescence was performed. The results confirmed that a high temperature drastically reduced the photosynthetic assimilation rate caused by the non-stomatal (biochemical) limitation of photosynthetic processes. On the other hand, the chlorophyll fluorescence indicated only a moderate level of decrease of quantum efficiency of photosystem (PS) II (Fv/Fm parameter), indicating mostly reversible heat stress effects. The heat stress led to a decrease in the number of active PS II reaction centers (RC/ABS) and overall activity o PSII (PIabs) in all genotypes, whereas the PS I (parameter ψREo) was negatively influenced by heat stress in the non-acclimated variant only. Our results showed that the genotypes differ in acclimation capacity to heat stress, and rapid noninvasive techniques may help screen the stress effects and identify more tolerant crop genotypes. The acclimation was demonstrated more at the PS I level, which may be associated with the upregulation of alternative photosynthetic electron transport pathways with clearly protective functions.

Modelling of Energy Storage System from Photoelectric Conversion in a Phase Change Battery

The essence of the research was to model the actual energy storage system obtained from photoelectric conversion in a phase change accumulator operating in a foil tunnel. The scope of the work covered the construction of four partial models, i.e., electricity yield from solar radiation conversion for three types of photovoltaic cells (mono- and polycrystalline and CIGS), energy storage in a PCM battery, heat losses in a PCM battery and energy collection from photoelectric conversion in PCM battery. Their construction was based on modelling methods selected on the basis of literature review and previous analyses, i.e., artificial neural networks (ANN), random forest (RF), enhanced regression trees (BRT), MARSplines (MARS), standard multiple regression (SMR), standard C&RT regression trees (CRT), exhaustive CHAID for regression (CHAID). Based on the analysis of the error values (APE, MAPE, ΔESRt), the best quality models were selected and used in the further part of the work. Based on the developed models, a simulation of the influence of the size of the photovoltaic power plant and the type of cells on the process of storing energy from photoelectric conversion in a PCM battery was carried out. For the battery under study, a PV power output of 9 kWp for mono and polycrystalline panels and 13 kWp for CIGS panels is recommended for reasons of energy storage efficiency. The obtained results made it possible to develop a model determining the amount of energy stored in a phase change battery depending on the power of a photovoltaic power plant and variable solar conditions. In order to store the greatest amount of energy, we should choose a source with a capacity to produce at least 70 kWh of electricity per day. In the final stage of the work, the indicators of solar radiation energy storage in the tested phase change accumulator were determined. For the battery tested, the solar energy storage efficiency can reach 12–13% for mono and polycrystalline panels and less than 7% for CIGS panels.

The Influence of Hydroponic Potato Plant Cultivation on Selected Properties of Starch Isolated from Its Tubers

Starch is a natural polysaccharide for which the technological quality depends on the genetic basis of the plant and the environmental conditions of the cultivation. Growing plants under cover without soil has many advantages for controlling the above-mentioned conditions. The present research focuses on determining the effect of under cover hydroponic potato cultivation on the physicochemical properties of accumulated potato starch (PS). The plants were grown in the hydroponic system, with (greenhouse, GH) and without recirculation nutrient solution (foil tunnel, FT). The reference sample was PS isolated from plants grown in a tunnel in containers filled with mineral soil (SO). The influence of the cultivation method on the elemental composition of the starch molecules was noted. The cultivation method also influenced the protein and amylose content of the PS. Considering the chromatic parameters, PS-GH and PS-FT were brighter and whiter, with a tinge of blue, than PS-SO. PS-SO was also characterized by the largest average diameters of granules, while PS-GH had the lowest crystallinity. PS-SO showed a better resistance to the combined action of elevated temperature and shear force. There was a slight variation in the gelatinization temperature values. Additionally, significant differences for enthalpy and the retrogradation ratio were observed. The cultivation method did not influence the glass transition and melting.

Modelling of the Electric Energy Storage Process in a PCM Battery

The essence of the research was the modeling of a real electric energy storage system in a phase change battery operating in a foil tunnel. The scope of the work covered the construction of two partial models, i.e., energy storage in the PCM accumulator and heat losses in the PCM accumulator. Their construction was based on modeling methods selected on the basis of a literature review and previous analyses, i.e., artificial neural networks, random forest, enhanced regression trees, MARS plines, standard multiple regression, standard regression trees, exhaustive for regression trees. Based on the analysis of the error values, the models of the best quality were selected. The final result of this study was the construction of such a model of the process of storing electricity in a PCM battery, characterized by the mean absolute percentage error forecast error of 1–2%. The achievement of this goal was possible thanks to the use of the artificial neural networks model for which the input variables were the amount of energy supplied to the accumulator and the temperature of the heat storage medium.

Experimental and modeling approach to heat and mass transfer in a porous bed of a rock-bed heat accumulator

The paper presents the results of the research concerning heat and mass transfer phenomena occurring in a porous bed of a rock-bed heat accumulator. The tests were carried out in a standardized semi-cylindrical foil tunnel, commonly used in horticulture farming, equipped with a rock-bed accumulator covering the area of 74.8 m2. Input data for the analysis were obtained from experimental studies carried out from April to October, including 435 charging and 409 discharging cycles. During the experiments, the process parameters, such as temperature, relative humidity and air flow velocity, in different measuring points of the system were recorded. Using modern mathematical modeling a multi-scale analysis was carried out to quantify the intensity of heat and mass transfer between the flowing air and bed particles, as well as the degree of humidification or drying of the air flowing out of the accumulator. The values of convective heat transfer coefficients and mass transfer coefficients for individual charging and discharging cycles were determined and correlation equations for them were found. The conducted analysis showed that the coefficients determined by measurements fit the proposed regression models with the following values of R2 (coefficient of determination): 0.83 and 0.86 for mass transfer coefficient (condensation and drying, respectively), and 0.85 for convective heat transfer coefficient. Using the similarity theory, the equations for calculating Nusselt and Sherwood numbers were found, from which the coefficients adopted for analysis can be derived. It was also analyzed to what extent the obtained results differ from the results presented by other authors describing similar issues. The originality of this research consists in determining the values of heat and mass transfer coefficients for the air flow through the porous bed and finding their functional dependencies on the input parameters. The research results fill the gaps in scientific knowledge; moreover, they can be applied in heat transfer engineering issues, such as modeling heat and mass processes occurring in a rock-bed accumulator in a greenhouse or in other facilities, thus enhancing the energy efficiency of the designed systems.

The Effect of Open Field and Foil Tunnel on Yield and Quality of the Common Thyme (Thymus vulgaris L.), in Organic Farming

Common thyme (Thymus vulgaris L., Lamiaceae) is regarded as one of the most important aromatic plant used both as a spice and medicine. The aim of this work was to investigate the yield and quality of common thyme grown for a fresh herb, cultivated in the organic farming system, within the temperate climate in Poland. Two methods of cultivation were applied: open field and foil tunnel. Three successive cuts of herb were possible to obtain during vegetation season, from the middle of July until the end of September. The raw material was analyzed for the content of essential oil (by hydrodestillation), phenolic acids and flavonoids according to Polish pharmacopeia (PP 6th). The composition of essential oil was determined by gas chromatography-mass spectrometry (GC-MS). Sensory evaluation was carried out by quantitative descriptive analysis (QDA) with a trained panelist. The yield of fresh herb was visibly higher when regards cultivation under foil tunnel in comparison to open field, reaching up to 6.74 kg FW × 10 m2. The content of essential oil as well as the percentage share of thymol (a dominant constituent, achieving up to 57.08%) decreased with consecutive herbal cuts. The opposite result was observed for phenolic compounds (phenolic acids and flavonoids). It was shown that the amount of flavonoids was similar in both variants of cultivation, while phenolic acids were accumulated at higher level in the open field conditions. Sensory analysis indicated on slight differences in odor and taste attributes, between samples of fresh herb collected from open field and foil tunnel.

Effect of 5-Aminolevulinic Acid (ALA) on the Biochemical and Physiological Parameters of Postharvest Quality of Polygonatum multiflorum L. All. ‘Variegatum’ Cut Foliage

Due to the dynamic development of the floriculture market, new species and varieties of plants that can potentially be used as a source of cut greenery are constantly being sought. The experiment was conducted to analyze the effect of the cultivation site (unheated foil tunnel and open field) and treatments with the Pentakeep V formulation (0.00%, 0.02%, 0.04%, and 0.06%) on the vase life and postharvest quality of Polygonatum multiflorum ‘Variegatum’ cut foliage. There was a positive effect of the cultivation in the unheated foil tunnel on the vase life and biochemical parameters, namely the electrolyte leakage (EL), thiobarbituric acid reactive substances (TBARS), chlorophyll a + b (Chl. a + b), proline, peroxidase (POD), and ascorbate peroxidase (APX), of P. multiflorum cut foliage. Foliar application of Pentakeep V formulation at concentrations of 0.04% and 0.06% contributed to a decrease in the TBARS content in the P. multiflorum cut leaves, regardless of the plant cultivation site. Additionally, it reduced proline production in cut leaves of P. multiflorum cultivated in the unheated foil tunnel, which was confirmed by the analyses carried out after the 30 days of the experiment. Furthermore, the exogenous application of ALA during P. multiflorum cultivation inhibited POD activity, irrespective of its concentration and the site of plant cultivation.

The Use of Artificial Neural Networks for Forecasting of Air Temperature inside a Heated Foil Tunnel

It is important to correctly predict the microclimate of a greenhouse for control and crop management purposes. Accurately forecasting temperatures in greenhouses has been a focus of research because internal temperature is one of the most important factors influencing crop growth. Artificial Neural Networks (ANNs) are a powerful tool for making forecasts. The purpose of our research was elaboration of a model that would allow to forecast changes in temperatures inside the heated foil tunnel using ANNs. Experimental research has been carried out in a heated foil tunnel situated on the property of the Agricultural University of Krakow. Obtained results have served as data for ANNs. Conducted research confirmed the usefulness of ANNs as tools for making internal temperature forecasts. From all tested networks, the best is the three-layer Perceptron type network with 10 neurons in the hidden layer. This network has 40 inputs and one output (the forecasted internal temperature). As the networks input previous historical internal temperature, external temperature, sun radiation intensity, wind speed and the hour of making a forecast were used. These ANNs had the lowest Root Mean Square Error (RMSE) value for the testing data set (RMSE value = 3.7 °C).

Yield and quality of ‘Greek oregano’ (Origanum vulgare L. subsp. hirtum) herb from organic production system in temperate climate

Oregano (Origanum vulgare L.) is an important medicinal and aromatic plant. The purpose of this study was to determine the possibility of organic cultivation of ‘Greek oregano’ (Origanum vulgare L. subsp. hirtum) within temperate climate conditions in Poland. Two variants of field experiments were applied: open field and foil tunnel. Results showed that plants cultivated under foil tunnel were characterized by almost twice the mass of the herb when compared to those from open field (76.49 and 49.44 g of dry mass per plant, respectively). The herb was analyzed for total content of essential oil, phenolic acids, flavonoids, chlorophyll a and b. The composition of essential oil was determined by GC–MS (gas chromatography - mass spectrometry). Raw material harvested from plants cultivated in foil tunnel was distinguished by higher content of flavonoids, chlorophyll a and b as well as essential oils in comparison to those from open field. However, the content of phenolic acids was higher in herb collected from plants grown in open field. There was no clear relationship between the cultivation method and essential oil composition, where carvacrol was a dominant (up to 73.85%). Observed differences concerning both yield and content of biologically active compounds seems to be associated with various climatic parameters (especially temperature) recorded in both variants of cultivation. The results of sensory evaluation (Quantitative Descriptive Analysis) showed that the herb from foil tunnel was characterized by a slightly higher intensity of coniferous and less spicy odor notes, as well as more astringent taste, in comparison to the one from open field. In general, the results indicate that ‘Greek oregano’ can be successfully cultivated in Polish climate, in organic system.

First Report of Downy Mildew Caused by Plasmopara muralis on Boston Ivy (Parthenocissus tricuspidata) in Poland

Given its decorative foliage and leaf discoloration in autumn, Boston ivy (Parthenocissus tricuspidata Siebold & Zucc.) is mainly used in garden compositions. The climber is commonly grown in Poland, because it is characterized by rapid growth and low soil and climatic requirements. ‘Veitchii’ is the most common variety cultivated in Poland. In May 2017, the symptoms of downy mildew on Boston ivy plants were observed in one of the ornamental plant nurseries in Mazowieckie Province (52°06′42″N, 20°59′13″E), where disease incidence reached 80%. The disease symptoms on the plants were noted first on lower and then on upper leaves. On the upper surface of the lamina, there were reddish lesions on older leaves and light green lesions on young leaves. In both cases, the injuries on leaves were delimited by veins, and on the lower surface monopodially branched colorless, straight or slightly curved sporangiophores with sporangia developed. The causal agent of downy mildew in Boston ivy was identified using morphological and molecular methods. The sporangia were hyaline, ovoid to shortly ellipsoidal, with a protruding pedicel. They measured (13.1 to) 14.7 to 22.1 (to 38.1) × (11.2 to) 12.3 to 16.3 (to 20.5) µm (n = 100). The length of ultimate branchlets of sporangiophores was (3.7 to) 5.1 to 8.9 (to 11.8) µm (n = 100). These measurements were similar to those obtained by Thines (2011). Koch’s postulates were fulfilled. The experiment was carried out twice. Five 1-year-old healthy P. tricuspidata seedlings (approximate height of 50 cm) growing in pots (diameter 13 cm) and one infected seedling were placed in a foil tunnel. The plants were sprayed with water to induce transfer of pathogen sporangia from the diseased onto healthy plants. Next, the tunnel was closed. In the control variant, six healthy plants were sprayed with water. The field experiment was carried out with three replications at a temperature 20 to 26°C and relative humidity of approximately 80%. After 10 days, the first symptoms of downy mildew were observed on the inoculated plants, whereas the control plants remained symptomless. Cytochrome c oxidase of the subunit II gene of mtDNA for the oomycetes isolated from P. tricuspidata was amplified with the use of oomycete-specific primers COX2-F (Hudspeth et al. 2000) and COX2-RC4 (Choi et al. 2015). It turned out that the downy mildew on the Boston ivy was caused by Plasmopara muralis. The sequence from the oomycete exhibited 100% similarity to a reference sequence for this pathogen (Thines 2011) deposited in GenBank (accession no. FJ394346.1). The obtained sequence was deposited in GenBank under the number MH492326. Downy mildew may seriously affect Boston ivy commercial production in nurseries. That is why further research is needed to develop recommendations for disease control. To our knowledge, this is the first report on the occurrence of P. muralis on Boston ivy in Poland.

Effect of mycorrhiza on yield and quality of lettuce grown on medium with different levels of phosphorus and selenium

Lettuce plants were grown in the foil tunnel in pots filled with peat substrate. The experimental factors were: concentration of phosphorus in the substrate (70 or 140 mg dm-3), inoculation of substrate with arbuscular mycorrhizal fungi (+AMF or –AMF) and concentration of selenium in the substrate (0, 6 or 12 mg dm-3). Mycorrhizal frequency in roots was affected by concentration of P, inoculation with AMF and interaction between these factors. Higher mycorrhizal frequency was found in plants inoculated with AMF and grown under conditions of lower P concentration. AMF did not affect an accumulation of Se in leaves. However, higher concentration of P and Se in the substrate affected Se concentration in leaves. The average yield of lettuce decreased with increasing level of Se in the substrate. The presence of Se in the substrate led to decrease of K, Mg, Fe, Cu and Mn content of plants. AMF did not have an effect on the content of sugars in leaves.

THE EFFECT OF SILICON ON MORPHOLOGICAL TRAITS AND MECHANICAL PROPERTIES OF Polygonatum multiflorum (L.) All. ‘VARIEGATUM’ CUT SHOOTS

Garden perennials are a source of floristry material produced in field or under covers. A perennial producing long, leafy shoots, which in flower arrangements might successfully substitute fern or palm leaves, is Polygonatum multiflorum. The variety characterizing with decorative white margined leaves is ‘Variegatum’. To improve their quality, the growth stimulator Actisil Hydro Plus, which contains 0.6% of active silicon in a form of orthosilicic acid was applied. The aim of the conducted experiment was to estimate the influence of silicon and a place of cultivation (tunnel and open field) on post-harvest quality determined with morphological features, vase life longevity and mechanical properties of Polygonatum multiflorum (L.) All. ‘Variegatum’ stems. The plants were sprayed with water solutions of Actisil in concentrations: 0.2%, 0.3%, and 0.4%, six times during the growing season in weekly intervals, starting from the first decade of May, always in the morning. It was stated that cultivation of Polygonatum in the unheated foil tunnel increases quality of shoots for cut greenery, determined with morphological features and post-harvest longevity. Cultivation of Polygonatum in a foil tunnel and spraying plants with Actisil in concentrations of 0.3 or 0.4% is advantageous due to possibility to increase a number of shoots from 20% to over 31%, their length from 9% to 11% and fresh weight from 52% to 71%, in comparison to control plants. It is advised to treat plants cultivated in a tunnel, with Actisil in concentration of 0.4% as it improved shoots quality evaluated with their diameter and lower leaves blade area. Spraying plants with Actisil in concentrations of 0.2–0.4% in the tunnel and 0.2% in field prolongs post-harvest shoots longevity by 3–4 days. Plants cultivated in the tunnel characterize with higher strength of shoots determined with higher maximum force causing permanent damage and lower stem deflection than plants cultivated in field. Plants grown in a tunnel and sprayed with Actisil in concentrations of 0.4% characterized with the strongest shoots after 14 days of storage, however a similar effect was observed with the concentration of 0.3% and in case of plants cultivated in field and sprayed with 0.4% of Actisil.

Geocomposite use in container nursery production of selected ornamental shrubs

Geocomposite, which is an innovative technology of superabsorbent material (hydrogels) occurring in a form of openwork discs closed in black agrotextile, reduces the negative impact of soil/substrate on the absorption capacity of hydrogel with simultaneous reduction of the negative impact of the hydrogel on the physical soil/substrate parameters. The aim of this research was to assess the influence of geocomposite use with different fertilizers and their doses (3 g Osmocote Plus 3-4M, 1.5 g Osmocote Plus 3-4M, 3×1 g YaraMila Complex) on biomass production of Prunus pumila var. depressa (Pursh) Bean and Diervilla lonicera Mill. cultivated in containers in an unheated foil tunnel. Fresh and dry biomass of both species was higher with the use of geocomposite, which did not affect root/shoot ratios for either taxa. For both species, fresh and dry shoots weight was the highest with 3 g Osmocote. The highest fresh and dry root weights and root/shoot ratios of Prunus was noted in 1.5 g Osmocote, while the fertilization had no effect on total weight of this plant. Diervilla obtained the highest fresh and dry root and total weight with 3 g Osmocote. The highest fresh and dry root/shoot ratio was noted in 1.5 g Osmocote. For both species, the highest fresh and dry biomasses were achieved by the use of geocomposite in combination with 3 g Osmocote fertilizer. The lowest fresh and dry shoot weights were obtained by both species with 1.5 g Osmocote fertilization without the use of geocomposite. The lowest fresh and dry root/shoot ratios occurred in treatments using 3 g of Osmocote without geocomposite application. The results of this research show that geocomposite use in container nursery production of ornamental shrubs had a positive influence on shoot and root growth.

The effect of substrates on yield and quality of strawberry fruits cultivated in a heated foil tunnel

The effect of substrates on yield and quality of strawberry fruits cultivated in a heated foil tunnel

Analysis of the efficiency of a hybrid foil tunnel heating system

The paper analyzes the efficiency of the hybrid system used to heat the foil tunnel. The tested system was built on the basis of heat gain in a cascade manner. The first step is to heat the water in the storage tank using the solar collectors. The second stage is the use of a heat pump (HP) in order to heat the diaphragm exchangers. The lower HP heat source is a cascade first stage buffer. In the storage tank, diaphragm exchangers used for solar collectors and heat pumps are installed. The research was carried out at a research station located in the University of Agriculture in Cracow. The aim was to perform an analysis of the efficiency of a hybrid system for the heating of a foil tunnel in the months from May to September. The efficiency of the entire hybrid system was calculated as the relation of the effect obtained in reference to the electrical power used to drive the heat pump components (compressor drive, circulation pump), circulation pumps and fans installed in the diaphragm heaters. The resulting effect was the amount of heat supplied to the interior of the object as a result of the internal air being forced through the diaphragm exchangers.

Assessment of the usefulness of selected media used in the rooting process of lavender cotton shoot cuttings

Abstract Lavender cotton (Santolina chamaecyparissus L.) shoot cuttings, obtained from two-year-old mother plants, were rooted in five different media under an unheated foil tunnel. Two ready-made and widely recommended media were used: Hartmann peat substrate and Ceres peat-coconut substrate, as well as three prepared mixtures: high peat + mineral soil, high peat + perlite and high peat + sand. The influence of medium type on the number of rooted cuttings and the quality of the root system was assessed for two cultivation times during a three-year study after eight weeks from the date of cutting. As far as the ready-made rooting substrates are concerned, Ceres peat-coconut substrate turned out to be better when compared with the Hartmann substrate. The number of high quality rooted cuttings was larger when media containing high peat mixed with either mineral soil or sand were used in comparison with the mixture of high peat and perlite.

The effects of storing heat excess in a stone battery in a horticultural premise

This work presents the results of research connected with the flow of air through a stone battery. The research was carried out in a foil tunnel with a four-section stone battery. The battery deposit consisted of porphyry stone of 30 – 63mm granulation. The process of inlet from the inside of a tunnel to a battery (manager using an algorithm) enabled the unbundling of heat storing cycle and the cycle of delivering the stored heat to the inside of the tunnel. The amount of heat and exchanged mass was described (in relation to the unitary surface and a particular cycle). Correlational equations were formed for the found values and they enable the calculation of a unitary heat stream and the masses of stone battery exchanged cycles.

Autumn Cultivation of Farewell-To-Spring (Clarkia amoena A. Nelson & J. F. Macbr.) in Unheated Foil Tunnel in Lower Silesia Condition

Autumn Cultivation of Farewell-To-Spring (Clarkia amoena A. Nelson & J. F. Macbr.) in Unheated Foil Tunnel in Lower Silesia Condition

Source of nitrogen affects the yield and quality of spinach cultivars grown for autumn harvest

Spinach can be grown for early harvest in the spring mainly for fresh market supply or for autumn harvest, used on a large scale for processing. The experiment was carried out in 2007–2009, and its aim was the determination of the effect of different nitrogen fertilizers (ammonium nitrate, calcium nitrate, ammonium sulfate, and Entec-26) on yielding and nutritional value of seven spinach cultivars (Greta F1, Industra, Markiza F1, Matador, Olbrzym Zimowy, Rembrandt F1, and Spokane F1), cultivated in foil tunnel for autumn harvest. The obtained data indicated that the highest marketable yield was provided by application of Entec-26 fertilizer. Similar yielding was also recorded for plants fertilized with ammonium or calcium nitrate, whereas significantly lower one resulted from fertilization with ammonium sulfate. Olbrzym Zimowy appeared to be the best – yielding cultivar, although Spokane F1 and Rembrandt F1 gave the results at comparative level. The application of ammonium sulfate and calcium nitrate contributed the least to the accumulation of nitrates in spinach leaves, whereas comparison of cultivars revealed the lowest nitrates accumulation in Matador. Furthermore, this cultivar also contained the highest amount of vitamin C, which was particularly apparent when Entec-26 fertilization was applied. The use of Entec-26 was associated with the highest accumulation of potassium and the lowest content of magnesium. The highest levels of potassium were found in Industra, magnesium – in Olbrzym Zimowy, and Greta F1 featured the highest content of calcium. Ammonium sulfate, assuring the best quality of the crop expressed by a high content of vitamin C and lower nitrates accumulation than other sources of nitrogen, can be recommended for the use in practice.