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The Use of Slow-Release Fertilizers as a Part of Optimization of Celeriac Production Technology

Abstract

The aim of this study was to assess the possibility of using slow-release fertilizers under intensive vegetable cultivation. To achieve the set research objective, a field experiment was set up in 2017, where slow-release fertilizer (NPK (%) 20-10-10+4MgO) was applied. The experiment comprised three levels of fertilization with the use of slow-release fertilizers, the control without fertilization, and the control fertilized with conventional fertilizers. The slow-release fertilizer was applied directly under each plant and in rows – approximately 8 cm below the root level. The designed systems were evaluated based on the size of commercial yield, productivity index, agronomic efficiency index, removal efficiency index, and physiological efficiency index. The results obtained in the field experiment indicate that the highest plant yield (54.22 Mg of commercial yield∙ha−1) was obtained at the highest dose of slow-release fertilizers (600 kg∙ha−1 applied in rows approximately 8 cm below the root level). In the case of direct fertilization, in the treatment with the highest dose of slow-release fertilizer, a reduction in yield was observed. The best results, in terms of equalizing the mass of individual roots, were obtained under conventional fertilization. The most favorable value of the productivity index was obtained in the variant where 400 kg∙ha−1 slow-release fertilizer was applied directly, while in the case of row application the best results were obtained at the dose of 600 kg∙ha−1. Celeriac fertilization with slow-release fertilizers under root may result in producing a yield of bigger differences in root mass, compared to conventional fertilization system.

Open access
Vertical Forces Acting on Cultivator Tines in the Aspect of Shearing Speed and Flexibility of Tines

Abstract

The objective of the paper was to determine the impact of the shearing speed and cultivator tines flexibility on the vertical forces value. The study was carried out in field conditions in sandy clay soil and the average moisture of 11.2%. The vertical forces acting on four “s” tines with flexibility of 0.0061; 0.0711; 0.0953 and 0.1406 m∙kN−1 were measured. Tines were ended with a cultivator point with the curvature radius of 0.17 m. Measurements were made for four shearing speeds (1.0; 1.7; 2.4 and 3.0 m·s−1) and the shearing depth of 11 cm. A stand for measurement of forces acting on soil shearing farm tools in field conditions was used. It was concluded that the shearing speed caused a linear increase of the vertical force but the growth gradient does not depend on the tines flexibility. It was also concluded that the increase in flexibility causes an initial increase and then decrease of the vertical force, which was described with the second degree parabola equation. Flexibilities, at which extremes of courses occur, grow along with the reduction of the shearing speed.

Open access
The Yield of Silphium Perfoliatum L. Depending on the Conditions of Cultivation

Abstract

The article presents the results of two-year studies on the influence of the method of sowing and the level of nitrogen application on the yield of seeds of Silphium perfoliatum L. − a new fodder crop for the conditions of Belarus. Silphium is precious for the nutritive value of green mass. According to the literature sources, dry matter contains 16-28% of protein, more than 60% of nitrogen-free extractives, 13-23% of sugars, high content of mineral substances, a small amount of fiber, adequate calcium and phosphorus, carotene, vitamin C. Mineral composition of Silphium contains 17.6% of dry matter, including 152.3 mg·kg−1 of ash. Macro elements: calcium – 18.1, phosphorus − 2.55, manganese – 4.48, potassium – 24.03, sodium – 0.40, sulphur – 0.40 mg· kg−1 of mg· kg−1 of dry matter. The mass of 1000 seeds was from 23.7 to 25.5 g. The seed germination was good and varied from 75% to 84%. It has been established that the best way to sow the Silphium is planting seedlings according to the 70x30 scheme. This option ensured the yield of seeds of 3.6 and 3.7 c/ha. The applying of increased doses of nitrogen fertilizers N90 and N120 and sowing seeds ensured the yield of seeds ranging from 3,6 to 3,9 c·ha−1.

Open access
Analysis of Broadband Antenna Radiation Pulses

Abstract

Electromagnetic energy can alter metabolic and biosynthetic processes and under certain parameters of pulsed EMF it can change pulse repetition frequency, operation cycle, power, exposure, as well as it can slow down and inhibit cell growth. MW irradiation range of RNA and DNA – containing virus reduces their infectivity. Inhibition of bacterial cultures growth, changes in phagocytic activity of protein biosynthesis, ultrastructural changes in the cells when exposed to EMF EHF. It was found in experiments with micro-organisms that biological effects of EMF on microorganisms wore a resonant character. One of the basic mechanisms of inhibitory action of EHF radiation on harmful microorganisms is the role of membranes in biological reactions of microorganisms on the EMR.

Open access
Analysis of Operation Performance in the Process of Machine Wood Harvesting with Fao Far 6840 Mini-Harvester

Abstract

The article presents analysis of operation of Fao Far 6840 mini harvester for machine wood harvesting. Analysis was made based on working day timing. The investigations were carried out on the area of Lubliniec Forest Inspectorate, Bór Forestry on the habitat forest site − fresh mixed forest where pine wood was obtained with the use of a harvester. Timing was carried out based on the registration of the exploitation time of a harvester with the use of a video camera and stopwatch and measurements of the obtained size grade. Based on the obtained results low values of performance in the exploitation change time 9.61 m3·h−1, and effective performance 12.14 m3·h−1 were reported. Low machine performance was affected mainly by conditions of harvesting, low log volume (at the average 0.62 m3) and concentration of trees. The head structure (applied feed system), weak work organization (short time of a single 6 hour shift) and weak skills of the machine operator were additional factors that reduced the performance

Open access
Assessment of Tree Sprouts Pruning with Various Types of Cutting Units

Abstract

Changes in horticulture induce fruit producers to introduce more efficient tree pruning systems. The increase of efficiency is related to application of various cutting devices, the effect of which on cultivated fruit trees has not been completely recognized yet. Therefore, the objective of the paper was to compare and assess the fruit tree sprouts cut with various types of cutting units. Four cutting units were applied in the study: pruning shears, anvil secateur, circular saw and chain saw and four cultivars of fruit trees: apple, pear, plum and cherry tree. A fractal dimension was used for assessment of the cutting quality that allows assessment of the spatial complexity of the image of the cut sprout. The obtained results allowed determination that the least sprout damaging cutting system is in case of the use of the anvil secateur and pruning shears (the best cutting quality) then circular and chain saw. It was also proved that susceptibility to damage is characteristic for the investigated fruit trees. Pear trees proved the lowest susceptibility to damages regardless the cutting unit.

Open access
Comparison of Proctor and Uniaxial Compression Tests for Selected Soils

Abstract

The objective of this paper was to compare the results of soil material compaction carried out with the use of the Proctor and uniaxial compression tests in order to find relations between these methods. Soil material in the form of loose mass was collected from the layer deposited at the depth from 35 to 60 cm in order to determine its typical properties (textural group, density of solid particles, humus content, reaction, plastic and liquid limits) and in order to compact it in the Proctor apparatus and in the uniaxial compression test. Results of both tests were used for construction of regression models reflecting the course of the unit stress (Pρdp), necessary to generate compaction equal to the dry density of solid particles obtained in the Proctor apparatus (ρdp) in relation to the sample moisture (w s). It was stated that the stress value Pρdp on the soil sample in the uniaxial compression test depends significantly on w s. It was proved that for the purpose of comparing the results of both tests, the uniaxial stress of samples must be performed in conditions of their lateral expansion. It was also proved that the use of the uniaxial test with possible lateral expansion of soil with a model sample, a diameter of which is 100 and the height is 30 mm, one may determine the obtained compaction with the use of the plate movement value.

Open access
Impact of Nanosilver and Nanocopper on Antifungal Properties of Plastic Elements in the Aspect of Their Use in Agri-Food Processing

Abstract

The paper presents results of microbiological research of plastic elements. Plastic elements were made of the polystyrene composition with addition of nanosilver and nanocopper with a laboratory extruder EHP 25ELine. Microbiological research was carried with regard to evaluation of antifungal impact of nanoadditives according to international standards with Cryobank (Mast Diagnostica). A positive impact of nanoadditives on antifungal properties of polystyrene elements produced by means of extrusion which is very favourable in the aspect of their use in agri-food processing.

Open access
Impact of Sediment Formed in Biogas Production on Productivity of Crops and Ecologic Character of Production of Onion for Chives

Abstract

The solid fraction, according to many researches, is an effective organic fertilizer, the activity of which is at the level of mineral fertilizers and even exceeds their effectiveness, while the use of the liquid fraction does not always give positive results. In the article the optimal concentration of the liquid fraction in water solution for fertilization during cultivation of onion for chives in soil was determined. Sediment from biogas production was obtained at the thermophilic fermentation (50ºC) of cattle manure in the laboratory institution which operated at the periodical regime of loading. Fermentation lasted 25 days. Seven variants of plant feeding were assessed: clean water (control), mineral fertilizers (solution of ammonium nitrate in water in the concentration of 1:25), unsolved liquid biofuel fraction and mixture of liquid fraction from the postferment with water in concentrations of 1:10, 1:50, 1:100, 1:500. It was determined that the highest efficiency was observed in case of fertilization of plants with the mixture of liquid fraction from postferment with concentration of 1:500. Along with the increase of liquid fraction concentration and fertilization of plants with water solution of mineral fertilizers, onion productivity dropped slightly. Fertilization of plants with the liquid fraction from postferment resulted in fractional dying of plants and reduction of efficiency. The crop control of nitrogen content proved that in case of every day watering of onion with clean water and mixture of liquid fraction with water concentration of 1:100-1:500 did not exceed the maximum admissible concentration which is 800 mg·kg−1. Thus, in case of onion cultivation for chives, taking into consideration the crop growth and low nitrogen content, it is recommended to use the mixture of liquid fraction with water of 1:500 concentration.

Open access
Kitchen and Garden Waste as a Source of Heat for Greenhouses

Abstract

The process of composting biological waste is a natural process – in which heat is released. Biological wastes generated in typical households in Poland – are mainly kitchen waste (KW) and green waste from home gardens (GGW – if they are owned). From the ecological point of view – the most advantageous method of their management is their utilization in the place of production. The paper presents a proposal for effective management of bio-waste arising by composting – with the simultaneous use of heat for greenhouse heating in autumn. This is to encourage residents to independently compost bio-waste – and increase the level of recycling of waste generated in Poland by 2020. Calculations for greenhouses were made – in accordance with the energy audit methodology. The obtained thermal balance results were compared with the actual temperature prevailing in the greenhouse in autumn. These calculations were the basis for calculating the amount of KW and GGW enabling effective heating of greenhouses in the autumn so that the internal temperature does not drop below 10ºC. It has been calculated that 22 kg of composted bio-waste (KW and GGW) will suffice to heat the greenhouse in October with an area of 18 m2.

Open access