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  • The use of Common duckweed (Lemna minor) as a biological filter in the rearing of hybrid African catfish (Clarias gariepinus x Heterobranchus longifilis)
    107-112
    Views:
    617

    The African catfish (Clarias gariepinus x Heterobranchus longifilis) is one of the most important fish species in Hungarian aquaculture. The larvae and juveniles are reared at high feeding rates, which can reach up to 10% of the biomass. Intensive feeding results in large amounts of effluent water, directly proportional to the intensity of fish production. The aim of this experiment was to investigate the potential of Common duckweed (Lemna minor) as a biological filter and its nutrient removal capacity during intensive fry rearing of the hybrid African catfish. In a recent study, two experimental recirculation systems, identical in water volume and design, were set up, in one of which duckweed was grown under aquaponic conditions, where the concentrations of nitrogen and phosphorus forms were monitored and the production parameters of the fish were determined. The results obtained from the experiment showed that the use of duckweed as a biological filter improves the water quality of the recirculation system. A significant amount of plant biomass was produced, which mainly reduced the nitrate and orthophosphate concentrations in the system water. As a consequence, the survival of hybrid catfish was improved, which also affected biomass growth, but had no effect on other parameters.

  • The impact of population management on urban and rural Hooded Crow populations
    119-123
    Views:
    328

    Hooded Crow (Corvus cornix), originally native to agricultural areas, has become widespread in urban areas in recent decades. However, this process has negative consequences on urban animals and humans. Due to these problems, the control of urban crow populations is needed. Crows also cause significant damage to wildlife management, and are constantly being controlled in rural areas as well. In this study, we compare rural and urban populations to find out whether hunting activities have a population reduction effect. In the rural population, the reduction is carried out by weapons and traps, while the urban crows are controlled using traps only. In both sample areas, crow nests were surveyed during the nesting period. 29 active nests were monitored in the rural area in 2021, and 39 in 2022. In the urban area, 44 nests were recorded in 2021 and 35 nests in 2022. In 2021, 30 individuals were removed in the rural area, and 84 in 2022. In the urban area, 223 individuals were removed in 2021 and 144 in 2022. Results show that the number of crows removed follows the number of active nests, so that the reduction of a given year is likely to have an effect on the following year's nesting population. Because traps mostly capture juvenile birds, reducing the breeding population in the city can only be achieved in the long-term. Considering this, it is likely that increased attention to population control can effectively maintain crow populations and reduce the problems they cause.

  • The potential use of Pediococcus spp. probiotic in aquaculture: A review
    99-106
    Views:
    614

    Aquaculture production has significantly increased over the previous few decades. However, antibiotics have been implemented regularly and extensively to overcome outbreaks of pathogens in aquaculture to cover the human needs for animal protein, leading to the appearance of resistant strains that may cause serious damages in the environment and also human health. In the last few years, the implementation of probiotics as an alternative technique to antibiotics use in fish production has achieved promising results in aquaculture due to their beneficial impact on fish health and growth performance. Among different types of probiotics, the Pediococcus spp. bacteria stand out as a promising probiotic for their beneficial impact to aquaculture. Thus, the current study has been conducted to give an overview about the interactions between Pediococcus spp. and aquaculture. In addition, this review highlights the role of Pediococcus spp in promoting growth performance, improving feed conversion ratios and the intestinal architecture, enhancing the immune response and inhibiting fish pathogens, thereby preventing or at least reducing the use of antibiotics. Practical use of Pediococcus spp. probiotic in aquaculture as feed additives through selected case studies is also considered.

     

  • Parameter optimization of an inductively coupled plasma mass spectrometer for measuring arsenic and selenium
    81-85
    Views:
    578

    In the last decades, an increased interest has evolved in arsenic and selenium. The aim is to understand the environmental, agricultural and biological roles of these elements. In the case of arsenic, the major reasons are the relatively high concentration of arsenic in marine biota (mg kg-1) and the arsenic contaminated drinking water bases of some Asian countries, as well as Hungary. The toxicity of higher level selenium content is also known; nevertheless, selenium is essential for several biological functions. Considering its essentialness, in our country, the insufficient selenium intake rate causes a lack of selenium. Measuring the concentrations of these elements provides crucial, but unsatisfactory information, as the speciation, i.e. the form of an element presented in a sample is also required.
    In both cases, the most suitable method to determine concentration is inductively coupled plasma mass spectrometry (ICP-MS). Our objective was to optimize the variable parameters of the ICP-MS to attain the lowest (the best) detection limit. For this purpose, we investigated the effect of parameter change on net signal intensity and relative signal intensity. With the optimized parameter settings, the limits of detection for arsenic and selenium were determined, which are 0,032 ng dm-3 for arsenic, and 0,097 ng dm-3 for selenium. 

  • The effect of the preparation method on the physical and chemical characteristics of propolis tinctures
    163-168
    Views:
    720

    The effect of the preparation method was examined with regards to the physical and chemical characteristics of the propolis tincture, namely the extraction time and the ethanol content of the extraction solvent to the dry matter, polyphenol, flavonoid, phosphorus, calcium and copper concentration, respectively. The dry matter, the polyphenol and the flavonoid content were the lowest in the water extract of the propolis; however, significant increase was noticed depending on the extraction time. Significantly higher concentrations were found in 50 V/V% tinctures. The highest dry matter and flavonoid contents were analysed in 100 V/V% tinctures, whereas highest polyphenol content was found in 80 V/V% tinctures. However, the differences were not significant in several cases between latter tinctures. Moreover, the increase was not determined in some cases depending on the extraction time. Phosphorus and calcium concentrations were decreased depending on the increasing ethanol content, whereas copper concentration was increased up to 80 V/V%. Higher increase was found in the case of 0 and 50 V/V% extracts than in 80 and 100 V/V% tinctures. Moreover, in latter cases, no significant differences were found on several occasions, depending on the extraction time. There was no connection between the flavonoids and the calcium as well as the phosphorus content, whereas flavonoids may be made complex with copper. However, the amount of the possible complex was negligible.

  • Preliminary results of the combined production of duckweed Spirodela polyrhiza and common carp (Cyprinus carpio) in an aquaponic system
    83-89
    Views:
    427

    As a result of population growth, increasin amount of food is needed, and agriculture is under an increasing burden to meet these needs. Traditional agriculture is often attacked due to its environmental impact. We must find alternative, environmentally friendly ways to produce more food. Aquaponics is a closed system in which we can produce both fish and plants at the same time. Duckweed species are small, aquatic, floating plants belonging to angiosperms. It can potentially be an alternative protein source, due to its high protein content, good amino acid supply, and rapid growth. Under suitable conditions, it doubles its weight in 2–4 days, and can reach a yield of 30 t ha-1 year-1in dry matter. It forms a carpet on top of the water and can be found in slow-moving or still waters. Since they are resistant to a wide range of nutrient concentrations, they are also suitable for cleaning wastewater (such as eutrophicated lakes, sewage reservoirs, liquid manure storage). Fish feed is the primary nutrient source for aquaponic systems, which usually contains fishmeal. If duckweed can be used as an alternative for fishmeal in the feed, it could improve the sustainability of the aquaponic and aquaculture systems. In this study, the aim was to develop an optimal harvesting protocol for duckweed Spirodela polyrhiza under aquaponic conditions. In a four weeks experiments, four harvesting protocols were set up, a control where only biomass measurements were made, a 25% group where 25% of the biomass at the time of measurement was harvested, and a 50% and a 75% group where at the time of measurement 50% and 75% of the biomass was harvested. Three replicates were used per treatment. We weighed the biomass every week and removed the amount corresponding to the group. Based on the preliminary results, it can be said that more biomass was obtained in the groups with the 25% harvesting protocol and the control group.

  • The current status, challenges and prospects of native pig production and large-scale farming in Laos
    155-161
    Views:
    801

    This review aimed to investigate the potential native pig development and the trend that large-scale farming may influence native pig production in Laos. The review found that native pigs were estimated to be around 88% of the total pig population in Laos in 2023. Commercial pig farming was found only in the main cities, particularly the central and southern provinces, which increased from 578 in 2019 to 703 farms in 2022 and 737 farms in 2023. Due to the serious economic crisis starting in 2021, many Lao pig producers stopped their businesses, leading to the decline of the commercial pig population by almost 30% in 2023 compared to 2022. The average pork per capita consumption in Laos in 2021 was estimated at about 14.2 kg. Though not as high as the backyard, commercial farms still contribute essentially to the pork supply in Laos (12%), increasing the volume from 87,628 tonnes in 2015 to 137,775 tonnes in 2024. The main native pig producers are small-scale rural farmers who have not yet improved productivity or reproductive performance, and the main purpose of their production is household consumption rather than market orientation. However, farmers, mainly in the main cities, improved them by cross-breeding native pig sows with Duroc boar for better lean meat. The main challenges for native production in Laos include poor farm setup and management, high cost of commercial feed, and poor breeding and genetic management. Therefore, creating awareness of the benefits of setting up a pig farm and management, providing better option strategies for utilising locally available feeds, and providing better strategies on pig breeding could improve native pig production in Laos.

     

  • Plant clinic in Nepal: An overview
    5-10
    Views:
    411

    Plant clinics play an important role in supporting farmers in growing healthy crops and achieving higher productivity in Nepal. The development and operation of plant clinics in Nepal are assessed in this study through a comprehensive analysis of the institution via literature review and interaction with key stakeholders. The plant clinic approach of the agriculture extension system started in Nepal in 2008, followed up with engagement with CABI and the Government of Nepal. Enhancement of farmers' knowledge and skill, encouraging sustainable farming methods, and ultimately increasing crop yields are the impact of plant clinics. However, there are some challenges faced during the implementation of plant clinics in the existing agricultural extension systems. In Nepal, the plant clinics are primarily operated by agricultural technicians with expertise in plant protection, as well as IPM farmer facilitators and community business facilitators after attending an intensive plant doctor's training. Plant clinics have been integrated into the agricultural extension system by agro-advisory service provider of the government of Nepal. Despite institutionalisation, policy support needs to be strengthened to ensure the sustainability of the different components of the (e.g., data management, validation, monitoring, localised content, etc.) plant clinic in Nepal.

     

  • Recovery and confirmation of Haemonchus contortus from abomasal contents of roe deer (Capreolus capreolus) in Eastern-Hungary (Biharugra): A diagnostic case study
    59-62
    Views:
    404

    Gastrointestinal parasites are ubiquitous. They occur both in wild and domesticated animals. Among such parasites of veterinary importance is the trichostrongyle worms, out of which the Haemonchus contortus species is regarded as the most pathogenic one in the small ruminant industry. The occurrence of this parasite in the sheep flock is now very well documented and an established fact in Europe, although the parasite was original of the warmer climatic region. Studies on the cross-transmission of H. contortus between the wild and domesticated animals are also on the rise although the question of the direction of transmission is still debated. This is an important area that needs to be addressed as it could potentially contribute indirectly to mitigating anthelmintic resistance. Hungary also has reported its share of the occurrence of the parasite, mainly in the sheep flock and a certain population of roe deer. The study presented here is the preliminary results of a diagnostic case study that confirms the presence of H. contortus in wild ruminant deer species that are close to the domesticated sheep population.

  • Daily soil carbon dioxide flux under different tillage conditions
    141-144
    Views:
    536

    Over the last few years, warming of the atmospheric layer near Earth's surface is increasingly experienced and researchers have also established that concentration of numerous greenhouse gases have risen over the past two centuries value. Change is basically a legitimate process - considering atmospheric concentration as well - but the change experienced during the past centuries could not have become this critical without the contribution of human activity. Due to the nature of the greenhouse effect, the result of a very fragile, complex process is experienced currently on Earth, which can be significantly unbalanced even by a slight change. Carbon dioxide emitted from the soil is involved in the global cycle and has an impact on the greenhouse effect. The rise in soil respiration may result in the further intensification of warming. In the scope of the present study, it was examined how carbon dioxide emissions of the soil evolve over a day. The results have been established based on the comparison of the effects of different parts of the day, tillage methods and irrigation.

  • The effect of sous-vide cooking on the antioxidant properties of oyster mushroom (Pleurotus ostreatus L.)
    177-184
    Views:
    734

    Oyster mushrooms (Pleurotus ostreatus L.) are renowned for their antioxidant, antimicrobial, and prebiotic properties. This study explores the antioxidant characteristics, activity, and β-glucan content in freeze-dried mushroom samples, investigating the influence of sous-vide cooking. Uncooked freeze-dried P. ostreatus and three pre-cooked freeze-dried samples (70, 80, 90 °C through 4 hours) were analysed for Total Polyphenol Content (TPC), Total Flavonoid Content (TFC), Radical Scavenging (DPPH), Ferric Reducing Antioxidant Power (FRAP), and β-glucans content via HPLC and Total Dietary Fiber (TDF) via enzymatic gravimetric method. Results indicate that uncooked mushroom powder exhibited superior antioxidant capabilities compared to cooked samples. The sous-vide cooked (80 °C) mushrooms displayed the highest total phenolic and flavonoid content. Moreover, pre-cooked (70 °C) mushroom powder demonstrated the highest β-glucan content, significantly surpassing the uncooked control sample. Notably, pre-cooked groups (80, 90 °C) demonstrated significantly higher TDF levels compared to uncooked sample. This research offers valuable insights into the potential use of mushrooms as high-antioxidant, antimicrobial, and prebiotic food or feed supplements, with broad implications across various fields.

  • Evaluation of chickpea (Cicer arietinum L.) in response to salinity stress
    105-110
    Views:
    823

    Soil salinity is a severe and expanding soil degradation problem that affects 80 million ha of arable lands globally. Chickpea (Cicer arietinum L.) is very sensitive to saline conditions; the most susceptible genotypes may die in just 25 mM NaCl in hydroponics. Approximately 8–10% yield loss in chickpea production is estimated due to salinity stress. However, it is still not established why chickpea is so susceptible to salt affection. Salinity (NaCl) impedes germination of seeds, though chickpea varieties considerably differ from one another in this respect. Some chickpea genotypes are more tolerant in the stage of germination, tolerating even 320 mM NaCl. The reasons of this variation are unrevealed; there is a shortage of knowledge about the germination abilities of chickpea genotypes in saline conditions. Nevertheless, the effect of salt stress on vegetative growth can be analysed in hydroponics, in pot or field conditions, regardless the experimental environment, the ranking of genotypes regarding salt resistance is coherent. Chickpea genotypes can be different in their ability to retain water, maybe under salt affection; the more salt tolerant lines can maintain higher water content in the shoots, while the more sensitive ones cannot. The identification of salt tolerant chickpea landraces based on developing genetic variability is a suitable strategy to combat against salinity problems arising in arid and semi-arid areas.

  • The study of the fertilizing effect of wheat straw ash in a greenhouse experiment
    47-51
    Views:
    467

    The effect of wheat straw ash as a fertlizizer was studied in a pot experiment with an acidic sandy loam soil (pHKCl=4.9) with weak K and P supply. The test plant was ryegrass (Lolium perenne). The treatments were the following: 1. control untreated soil, 2. NPK fertilizer, 3. small dose of ash (1.4 g kg-1), 4 large dose of ash (2.8 g kg-1), 5. small dose ash completed with NP fertilizers. Soil parameters (pHH2O, pHKCl, ammoinum-lactate soluble P, K, 0.01 M CaCl2 soluble PO43--P, K, Mn, Cu, Zn ) and plant parameters (yield, P, K, Ca, Mg, Zn, Mn uptake) were investigated. Based on the analysis of the straw ash sample and the results of pot experiment it can be stated that the wheat straw ash is suitable for the fertilization of the studied soil. The small dose ash completed with NP resulted in the largest yield increment (43%). In order of the treatments the pHKCl changes to: 4.9, 4.8, 5.2, 5.8, 5.1. As the N : P2O5 : K2O ratio is 0 : 1: 3.5 in the wheat straw ash sample, to reach optimal yield ash should be completed with N and P.

  • Evaluation of water balance in apple and pear trees
    193-198
    Views:
    612

    A significant proportion of the aboveground green and dry weight of the plant constitutes the foliage. The canopy is an important factor
    of plant growth. On one hand the canopy absorbs the solar energy, which is necessary for the photosynthesis, on the other hand accumulates
    the absorbed nutrients by the roots, and the most of the water-loss happens through the foliages. The determination of the full canopy is not
    an easy target. In our research we developed a measurement method to determine the leaf area. With the parameters of the examined tree
    (leaf length and maximum width) and the data of ADC AM 100 leaf area scanner we determined the k-value, with which we can easily and
    fast evaluate the leaf surface. Furthermore we defined from the water balance of compensation lysimeters the cumulative transpiration of
    fruit trees and the efficiency of water use of trees.

  • Seasonal variations in somereproductive parameters of Dorper Rams in Hungary
    17-20
    Views:
    721

    The purpose of the present study was to test the hypothesis that season has an affect on semen quality and scrotal circumference of Dorper rams. The experiment was carried out with six Dorper rams aged between 15 and 18 month. Semen samples were collected with artificial vagina and volume, concentration (x 109/ml), total sperm number/ejaculate (x 109), mass motility (0–5), progressive motility (%), scrotal circumference (cm) was observed. Significant differences (P<0.05) were observed in concentration, total sperm number/ejaculate, scrotal circumference in different seasons. Volume was the highest in autumn (1.4±0.5 ml) and the lowest in the spring (1.3±0.4 ml). Concentration of semen was lower in spring (2.6±1.5 x 109) and summer (3.3±1.5 x 109) as compared to fall (4.1±1.1 x 109) (P<0.05). Regarding total sperm number/ejaculate (x 109), scrotal circumference (cm) all the seasons differed significantly (P<0.05), although the season had no effect on mass motility and progressive individual motility (P<0.05). In conclusion the present study showed that semen quality parameters and scrotal circumference of Dorper rams were better in autumn than in the other sea- sons.

  • The effect of different genotype cattle grazing on the nutrient content of saline grasslands vegetation
    46-50
    Views:
    555

    Maintaining saline grasslands in good condition, preserving their yield and diversity is important not only for the purpose of nature conservation, but also for farming. Therefore, the primary purpose of our study is to analyse the effect of pasture use of the smaller weight extensive and the larger weight intensive beef cattle on the grassland vegetation and nutrient content. In this way, we can answer the question whether grazing for nature conservation can be achieved with more profitable, more economical and more intense varieties.

    The tests were carried out in May 2016 and May 2017, in the Hortobágy National Park (Pap-ere and Zám puszta), where a total of 16 sample areas were analysed. These areas are grazed with extensive beef cattle (Hungarian grey) and mixed genotype of intensive cattle. The associations were selected along a moisture gradient, such as wet salt marsh (Bolboschoenetum maritimi) and drier saline meadow (Beckmannion eruciformis). All the vegetative material collected both years in May was analysed for the following parameters: dry matter, crude protein, crude fibre and life-sustaining net energy content. We compared the effects of medium grazing (0.46 livestock/ha) and abandonment on vegetation and nutrient content.

    We examined the effect of (i) grazing, (ii) different grasslands (salt marsh, saline meadow) and (iii) grazing of different cattle breeds (Hungarian grey, intensive beef) on the nutrient content of the vegetation of grasslands Based on our results, it was found that grazing had an impact on crude protein and life-sustaining net energy content. The highest crude protein content (12.75 m/m%) was obtained in the year 2017 in the area where higher density had been grazed for two years. For the lifesustaining net energy, the highest value (5.05 MJ/kg d.m.) was also obtained in 2017 and the lowest in 2016. Furthermore, it was found that there was no significant difference between the effect of the two cattle breeds on the parameters examined. Significant effects were observed only in the case of life-sustaining net energy: in the area of intensive beef cattle we received a higher value (5.15 MJ/kg body weight) than in the area with extensive beef cattle (4.96 MJ/kg body weight).

    Our results have also shown that cattle grazing is of the utmost importance for the maintenance of both wet and mesophilous habitats. Based on our three-year study, we can say that grazing by both extensive and intensive cattle breeds is suitable for the management of saline habitats.

  • Using of e-learning in agricultural training programs
    117-124
    Views:
    178

    We use the Moodle at the University of Debrecen, Businessand Agricultural Department since January 2007. The Moodle is an open source Learning Management System. Learning Management System (or LMS) which is a software package, which enables the management and delivery of learning content and resources to students. Most LMS systems are web-based to facilitate „anytime, anywhere” access to learning content and administration. LMS tracks student progress in a course and indicates completions. At the least, learning management systems
    track individual student progress, record scores of quizzes and tests within an online learning program, and track course completions. The Moodle has more and more function at our Department in education. In January we worked to introduce Moodle in our Faculty. Therefore, we took lessons for the tutors about the usage of the Moodle. Our aim was to develop such a learning system, which is an integral part of  educational process,
    to improve the efficiency of agricultural higher education.

  • Coherence and connection between the good pond culture practice and the environment conscious management
    60-73
    Views:
    193

    According to the data indicating the decline and restructuring during the past decade, as well as the trend in the European Union member states, it can be expected that the role of traditional agriculture and fish production in direct rural employment decrease further. This also values those strategic directions for restructuring that will lead fishculture from quantity driven to quality production along with sustainable development (i.e. environmental conscious production) and multifunctional farming. This way the economic and social tensions caused by the concentration of the production and labour output can be mitigated.
    It is laid in the 1257/1999 Act on rural Development that farmers that enrol the agri-environmental scheme should follow the “Good Agricultural Practice” on the whole managed area. In case of agri-environmental schemes this is a precondition for which no grants are given.
    The adaptation of “Good Agricultural Practice” in fishproduction,where it is called: “Good Pond Culture Practice” is considered important on the basis of the above mentioned. This programme is undertaken in co-operation with the Research Institute for Aquaculture, Fisheries and Irrigation, University of Debrecen, Faculty of Agricultural Economics and Rural Development and the Association of Hungarian Fish Farmers and Product Council.
    The European Commission proposed the formulation of the European Fisheries and Aquaculture Fund (EFAF) for the period 2007-20013, which will replace the Financial Instruments for Fisheries Guidance (FIFG), but it also consists of several new elements and will be working differently, too. According to the proposal the budget for the Fund will be nearly 5 billion EUR (4963 million EUR). The development level of aquaculture and fisheries and the social and economic significance in the given member state will be considered when distributing the Fund between the Member States.
    According to the plan the Fund is organised along five priority axes, of which the most important for the Hungarian fisheries sector is No. II: Aquaculture and the processing and marketing of aquaculture and fisheries products. The main measure areas are the followings:
    1. investment support for aquaculture;
    2. support for aquatic-environmental schemes;
    3. environmental- and animal health issues;
    4. investments in processing and marketing
    In case of accessing support under measure area No. 2 farms are obliged to meet the requirements of the scheme beyond the “good management practice” for 5 years, which is to be supervised by the approved body of the Member State. For this reason our work is considered to be substantial.
    Approval of the application of “Good Pond Culture Practice” is based on two elements: first the prevailing environmental and nature conservation regulations, as well as the list of controllable conditions in the new agri-environmental agreements are to be met. “Good Pond Culture Practice” are to be conducted on the whole farm area. Its main elements are:
    - nutrition management,
    - feeding,
    - pond maintenance,
    - stocking,
    - harvesting,
    - animal welfare (storage and over-wintering).

  • Cross-Sectional Examination of Agricultural Firms in Relation to the Leaders’ Attitude
    261-269
    Views:
    89

    As a PhD student at the Management Department of Debrecen University my project was to find examine circumstances of agricultural business entities in connection with structural, social and economic changes. This topic is integral part of the research program „Functional Study of Business-Management”, specified the topic „Structural Management Researches”.
    My setting of objectives were to find any connection between changes and attitude of leaders. I tried to explore the direction, tightness and tendencies of these relations, to choose some special management-method, which ones are much more succesfull than the other ones during the change-managing process. The base of my experiences are the results of special questionnaires, which were sent to several member of different type of enterprises relating to agricultural activity.

  • The role of cultivar susceptibility and vineyard age in GTD: examples from the Carpathian Basin
    57-63
    Views:
    500

    Grapevine trunk diseases (GTDs) are among the most severe problems in viticulture worldwide. The exact etiology and the role of endophytic microorganisms is not known yet and there is no adequate protection or curative treatment against the disease. Hungarian wine regions are also affected by the disease, and there is restricted information about the rate of infection nation-wide and about the susceptibility of the Hungarian cultivars.

    The main objectives of our research are to measure the symptom expression and the damage caused by GTDs, to understand the epidemiology and etiology of the disease to establish a foundation of a proper disease management.

    Cultivar susceptibility groups were created with the aim to allocate some Hungarian cultivars and the role of vineyard age was also examined in symptom expression.

  • Evaluation some important microbiological parameters of the carbon cycle in chernozem soils profiles
    33-39
    Views:
    414

    Some chemical and microbiological properties of the carbon cycle were investigated in three chernozem soil profiles. The soil profiles originated from a long term fertilization experiment (potato) of the University of Debrecen, Látókép, Kryvyi Rig Botanic Garden (grassland) and a large-scale farm (sunflower) of Ukraine. The results of the organic C-content, total number of bacteria, microscopical fungi, cellulose decomposing bacteria, CO2-production, microbial biomass carbon and saccharase and dehydrogenase activities were compared and evaluated with the help of correlation analyses. Close correlation was found between the organic carbon content and the number of microscopical fungi,, saccharase and dehydrogenase enzymes’ activities, as well as close correlation was found between the dehydrogenase activity and microbial biomass-C and saccharase activity.

  • Effect and interaction of crop management factors and crop year on the yield of maize (Zea mays L.)
    31-41
    Views:
    513

    The aim of this study was to determine the combination of treatment levels of crop management factors which can optimize and sustain maize yield under varying climatic conditions. The effect of winter wheat forecrop, three tillage systems (Mouldboard-MT, Strip-ST, Ripper-RT), two planting densities (60,000 & 80,000 plants ha-1), three fertilizer levels (N0-control, N80, N160 kg ha-1) with four replications in irrigated and non-irrigated treatments were evaluated over a five year period, 2015–2019. The obtained results revealed that growing season rainfall positively correlated with yield, whereas, temperature negatively correlated with yield. Impact of adverse weather on yield was less severe in biculture, irrigated plots, at lower planting density (60,000), lower fertilizer rate (N80) and in RT and ST, compared to MT. In years with favorable rainfall, yields of MT and RT were significantly (P<0.05) higher than ST. However, in a less favorable year, such as 2015, with 299 mm growing season rainfall and the lowest July rainfall (59% below mean) there was no significant difference (P>0.05) in yield among the three tillage treatments. Higher planting density (80,000), and fertilization rate (N160) in tandem with MT are treatments combination conducive for high yield under favorable climatic conditions, whereas, in years with low rainfall and high temperatures, RT and ST offer alternative to MT for optimum yield with 60,000 plants ha-1 and N80 treatment level. Crop year effect accounted for 20.7% of yield variance, fertilization 35.8%, forecrop 12.8%, plant density 3.4%, tillage 1.2% and irrigation <1%. It is conclusive that with proper selection of the appropriate levels of agrotechnological inputs the adverse effect of weather on yield can be mitigated.

  • Managing risk using real options in company’s valuation
    125-132
    Views:
    331

    The valuation of company is very important because provides information about the current value/situation of company, and through this, provide the opportunity of choosing the best company’s growth alternatives. The future strategic decisions are characterized by lack of knowledge, information, so all measures of company’s growth are closely linked with uncertainty and risk. The company’s valuation process is also related with uncertainty and risk. The risk may result both from the assessed assets and the technique used. In literature, we could find three approaches for risk management: capital budgeting based method, methods based on portfolio analysis and real options approach of risk management. Among them, the real options based methods is the most revolutionary approach for risk management. The advantages of the method, consists in the fact, that the process of establishing strategic decisions integrates the possibility of reversibility, delay and rejections, which isn’t it possible at two previous methods. The method also takes into account the total risk of company, so both the company-specific and systematic risk. In this study, I have used one of the best-known real option based method, the Black-Scholes model, for determining the option’s value. Determination of option value is based on the data of enterprise, which was tested Monte Carlo simulation. One of the basic assumptions of the Black-Scholes model is that the value of option is influenced by several factors. The sensitivity of option’s value could be carried out with so-called “Greeks”.. In the study the sensitivity analysis, was carried out with indicators Delta (Δ), Gamma (Γ) and Vega (ν). The real options based risk management determinations were performed in the R-statistics software system, and the used modules are 'fPortofio' and 'mc2d'. By using of real options method, I have calculated the average value of company capital equal with 38.79 million. By using simulation was carried out 1000 runs. The results of this show a relatively low standard deviation, small interquartile range and normal distribution. In the calculation of indicator Delta, could be concluded the value of company moves in 0.831 proportion to the price of options, the standard deviations of index is low, so the real option based method could be used with success in company’s value estimation. The Gamma index shows the enterprise value is sensitive just for large changes. The result of Vega reflects the value of option, so the company’s value volatility, which is small in this case, but this means a volatility of value. In summary, we can conclude that the call options pricing model, well suited for the determination of company’s value.

  • Connection Between Leadership and Communication
    248-255
    Views:
    134

    Discussing communicationis not an easy job as it is about one of the most important symptomps of life, which plays an important role in all social humanic processes. Ways and devices of communication, communicational system of society developed – while in constant connection – with daily activity, social relations, bodies and structure of society.
    Communication takes a prominent part in all forms of management. By the help of this article I would like to demonstrate what importance communication has according to literarure and what relationship can be experienced between communication and management. Is D’Aprix statement reliable saying “communication is management or more properly drafted management is communication”?!

  • Genetic diversity of the Hungarian draft horse assessed by mitochondrial DNA
    29-32
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    667

    Hungarian draft is a horse breed with a recent mixed ancestry. It was developed in the 1920s by crossing local mares with draught horses imported from France and Belgium. To genetically characterize the breed and to set up the basis for a conservation programme, we have employed a molecular marker: a 256-bp D-loop mitochondrial DNA fragment. We analyzed 124 horses representing Hungarian draft horses to assess the maternal phylogeography of the breed. Sequence analysis of a 256-bp segment revealed a total of 34 haplotypes with thirty-four polymorphic sites. High haplotype and nucleotide diversity values (Hd=0.953±0.001; π=0.024±0.001) were detected. The average number of pairwise differences were k=5.998. This breed counts 800 mares today, and only survive due to breeding programmes, this way each haplotype frequency depends on the extent to which mares are involved into the breeding. The reduced number of surviving maternal lineages emphasizes the importance of establishing a conservation plan for this endangered breed. Due to the revealed 34 polymorphic sites we could presuppose twelve maternal linages, which could be a first step for making a breeding programme.