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  • The effect of dissolved oxygen on common carp (Cyprinus carpio) and basil (Ocimum basilicum) in the aquaponics system
    89-96
    Views:
    275

    Aquaponics is an integrated system that combines fish farming (aquaculture) and hydroponic plant production. The objective of this study was to examine how the level of dissolved oxygen with or without an air pump affects water quality, fish output and plant growth parameters for common carp (Cyprinus carpio) and basil (Ocimum basilicum).

    Ebb – and flood aquaponics systems (with automatic syphon) was used. Two treatments were set in this experiment, one of which was the aquaponics system without air pump (unit I), where water of the plant bed was pumped two directions, one falling back to the fish tank oxygenating the water the other was pumped to the hydroponics unit. The other system (unit II) was designed with an air pump.

    In the course of the study, water quality parameters, such as oxygen saturation, dissolved oxygen (DO), electrical conductivity (EC) and nitrite were significantly different (p<0.05). Total basil biomass was higher in unit II. (5367.41 g). The final biomass of common carp were
    2829.45 g ± 79.24 and 2980.6 g ± 64.13 g in unit I and unit II respectively. Weight gain (WG) and specific growth rate (SGR) showed no significant differences (p>0.05) between the treatments. 

  • Evaluation some important microbiological parameters of the carbon cycle in chernozem soils profiles
    33-39
    Views:
    154

    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.

  • Using of e-learning in agricultural training programs
    117-124
    Views:
    62

    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.

  • Examining the production parameters of European perch (Perca fluviatilis) juveniles under different lighting conditions
    149-153
    Views:
    160

    European perch (Perca fluviatilis) is a native predatory fish in Hungary, and a promising new species of fresh water aquaculture nowadays. The European perch can be characterized by a high stress sensitivity during the intensive rearing, thus the optimization of environmental conditions has significant importance in the early life stages of fish. The aim of our study was to determine whether the light intensity and darkening of the water by humic acid affect the survival and growth performance of European perch juveniles. The experiment lasted for 28 days. Rectangular aquariums were arranged in 3 lines, the test environment consisted of 24 units. The experiment was set up with 10–10 fish per aquarium, total of 240 individuals. The average wet body weight of the fish at the start of the experiment was 1.69 grams. During the experiment, 6 treatments in 4 replicates were set up. In the first row, we set up 305.6±66.0 LUX (L), in the second row 118.0±24.4 LUX (C), and in the third row (D) 17.0±8.6 LUX illumination was set up. In each row the water of four aquariums were darkened by the addition of humic acid (H) (L, LH, C, CH, D, and DH). At the end of the experiment high survival rate was observed in all treatments. Examining the survival rate, the best results were found in the strongly illuminated treatments (L; LH- SR%=100±0.00). The observed mortality was caused by cannibalism. Regarding the individual body weight, the best results were shown by the treatments where the aquariums were illuminated with lower light intensity (C: 4.66±0.33 grams) and the aquarium water was darkened by humic acid (CH: 4.93±0.15 grams). The results of the C and CH groups were significantly better compared to the other treatments, however, they did not differ statistically from each other. The darkening of the water had a positive effect on the individual body weight of fish reared under full light (L: 3.73±0.28 grams; LH: 4.33±0.28 grams), whereas in the case of fish reared in the lowest illumination, the addition of humic acid did not affect the results (D: 3.78±0.15 grams; DH: 3.80±0.26 grams). In case of SGR (C: 3.64%/day and CH: 3.74%/day) and FCR (C: 0.84 g/g and CH: 0.78g/g) the best results were obtained by the C and CH treatments, also.

  • Comparison of the technological background of aquaponic systems
    47-52
    Views:
    260

    Aquaponics is the combined culture of fish and plants in recirculating aquaculture systems, an ecologically sustainable horticultural production technique with long traditions.

    The objective of this study is to compare flood-and- drain, and the water crossflow system and examine the differences in the water quality, fish yield and plant growth parameters for Common carp (Cyprinus carpio) and basil (Ocimum basilicum). During the study, water quality parameters of two treatments were compared in temperatures, pH, EC and NON were significantly different (p <0.05). Leaf area of the basil plants grew to an average of 20.37 cm2 (± 9.02 cm2). The plants’ biomass production was significantly different (p< 0.05) in the two systems. The biomass production showed lower yield, 458.22 g (± 214.59 g) in the constant flow system that in the flood- and- drain system 692.9 g (± 175.82 g). Fish Growth parameters were better in constant flow system (FCR 5.48 g/g ± 0.19). However, the specific growth rate (SGR) demonstrated that fish grew faster in flood- and- drain system 1.38 %/day (± 0.29).

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

    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).

  • Managing risk using real options in company’s valuation
    125-132
    Views:
    133

    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.

  • Evaluation of chickpea (Cicer arietinum L.) in response to salinity stress
    105-110
    Views:
    202

    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.

  • Genetic diversity of the Hungarian draft horse assessed by mitochondrial DNA
    29-32
    Views:
    201

    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.

  • Evaluation of water balance in apple and pear trees
    193-198
    Views:
    102

    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.

  • Analysis of the situation of domestic game damage and forage ground management
    5-8
    Views:
    134

    Game damage is an important problem in home wildlife management, because game managers pay more and more money for game damage year by year. Crop fields can do an appreciable part in reduction of game damages. The aim of the research is to survey the situation of domestic game damage and wildlife forage ground management. (Which are the most used plants on crop fields, how current are the using of seed mixtures, which are the most typical game damages, as well as which are the most applied game control methods?)

    It can be stated that the number of plant species sown on crop fields is quite low. Mostly corn and alfalfa are raised, though besides those many other plants are suitable to grow on crop fields. Rising value of game damage and big proportion of the agricultural game damage are well traceable from the questionnaires, too.

  • The effects of agrotechnological factors on winter wheat yield in humid cropyear
    162-167
    Views:
    77

    The effects of crop rotation, nutrien supply and crop protection technologies, as well as the appearance of the main ear- and leafdiseases
    (powdery mildew, helminthosporium leaf spot, leaf rust, fusarium) were studied on the crop yields of winter wheat variety MV
    Pálma during the 2009/2010 crop year. The experiments were conducted in triculture (pea – wheat – corn) and biculture (wheat – corn), at
    five nutrition levels, with the use of three crop protection technologies (extensive, conventional and intensive) at the Látókép Research Site of
    the University of Debrecen, Centre of Agricultural Sciences. Our results proved that the appearance of leaf- and ear-diseases were
    significant in the wheat cultures during the 2009/2010 crop year, because of the rainy, warmer than usual weather, the lodging, and the huge
    vegetative mass developed. The most severe infections by the four examined diseases after pea and corn pre-crops were observed at
    extensive crop protection levels, when fertilizers were used at the highest dose.
    Following corn pre-crop, in the case of all the three crop protection technologies the maximum rate of wheat yield results were achieved
    at N150+PK level. The highest yield was reached at intensive crop protection level (6079 kg ha-1). In triculture, in case of all the three crop
    protection technologies the maximum yields were achieved at N50+PK level; in extensive technology 5041 kg·ha-1 yield, in conventional
    technology 6190 kg ha-1 yield was realised, while in the intensive technological model the yield was 7228 kg ha-1.
    The relationship between yield and fertilizer amounts, the rate of pathogen contaminations, crop protection technologies and pre-crops
    was defined with correlation analysis in case of different crop rotations during the 2009/2010 crop year. Based on the results of the
    experiment, we found that in stands after corn pre-crop strong positive correlation was established between the crop protection level and the
    crop yield (0.543), the nutrient levels and the emergence of the four examined pathogens, and between the nutrient levels and the yield
    (0.639). Extremly strong positive correlation was observed between crop protection and yield (0.843) in triculture. Strong positive
    correlation was detected between the nutrient levels and the presence of the four examined pathogens, as well as between nutrient and
    lodging (0.688). Strong negative correlation was between the crop protection level and the four examined diseases both in biculture and
    triculture.

  • The launch on the way to development or the „revival”... (Comparisons of theoretical and practical approaches apropos of the change and crisis management process of smes and mature companies) .
    65-70
    Views:
    67

    Hungarian SMEs, just like those in other EU member states, often cease for various reasons. Among these factors are many, which should not necessarily turn out this way. These factors are studied in numerous countries while the attempt is also made to create the systems of conditions for these enterprises to recover – often through various aids and supports (from public supports to non-governmental initiatives). Among other things they are trying
    to organize those services with the help of which – if there is the slightest hope for survival – those SMEs in trouble or having serious difficulties could avoid going down by recovering from
    their problematic situation and getting improvements.
    These days this issue comes up more and more urgently in Hungary, as well. It has quite a few signs indicating that – among other things – the reports, the enquiries and commissions of the
    National Association of Change and Crisis Managers (VOE), all of which – just like "thermometers" – reflect this tendency well. 
    I have been doing research on this topic since 1993. As an expert I utilize them, and as a VOE member, vice president, then president I process the relevant Hungarian but mainly French
    experience on the subject. I intend to present those few theoretical and practical results and applicable experience I have reached this way in this presentation of mine.

  • The impact of climatic factors on the relative chlorophyll content and yield of a maize hybrid in a long-term experiment
    71-77
    Views:
    193

    The impact of the climatic factors of crop year on the relative chlorophyll content of maize was examined for three years. The examinations were carried out on the Látókép Experiment Site of the University of Debrecen on calcareous chernozem soil in a small-plot, non-irrigated long-term field experiment with strip plot design. In addition to a non-fertilised (control) treatment, nitrogen (N) fertiliser doses were applied as base and top dressing. The 60 and 120 kg N ha-1 base dressing doses were followed by two top dressing doses at the V6 and V12 phenophases.

    Averaged over the different fertiliser treatments, SPAD readings increased in all three years as the growing season progressed. The highes SPAD value increase was observed in the average crop year (2017) at the V12 phenophase (11.8), which further increased at the R1 phenophas, by 3,7. No significant Spad value difference was observed between the average (2017) and the dry year (2018) at the V6 growth phase. However, in the wet crop year (2016), the V690 treatment provided the statistically highest relative chlorophyll content (46.8). At the V12 phenophase, the base dressing dose of 120 kg N ha-1+30 kg N ha-1 (V6150) showed to be successful in two years (2016 and 2018), while in 2017, the base dressing dose of A60 was successful. The impact of crop year on relative chlorophyll content can be clearly shown at the R1 growth stage. In all three years, the significantly highest relative chlorophyll content could be achieved at different nutrient levels: A60 in 2016, V6150 in 2017 and V690.

    In a wet year (2016), higher yield could be achieved as a result of the 60 kg N ha-1 base dressing and 30 kg N ha-1 at the V6 growth stage (V690) as top dressing in comparison with 2017 and 2018, when higher fertiliser dose (120 kg N ha-1 base dressing and 30 kg N ha-1top dressing at the V6 growth stage) was needed to achieve a significant yield surplus.

    Altogether, averaged over the different treatments, the highest yield (12.48 t ha-1) was observed in the wet year, when the relative chlorophyll content was also the highest (50.6).

  • Relationship between the change of soil moisture content of different soil layers and maize yield
    19-25
    Views:
    151

    The development of chernozem soil water management and its relationship with maize yields was studied in a 30-years long-term field experiment with different crop-rotation systems (mono-, bi- and triculture), in three crop years with different natural precipitation: a drought (2007), a wet (2008) and a dry (2009 one. The relevant soil layer was divided to three sub-layers: (0–60 cm, 61–120 cm, 121–200 cm) in which the development of soil moisture content was investigated during the whole vegetation. From the results it can be stated that change of the water stock of the upper soil layer (0–60 cm) was the most intensive. Both the direct effect of natural precipitation and irrigation could be observed in the most obvious way in it. Yield result of maize and the highest water supply deficit values in the vegetation were compared in our work too. According to the results it was revealed that among the three studied crop rotation systems it was the monoculture, the success of production of which depends the most of water supply. The most favourable crop rotation system was the triculture from both the aspect of the yield of produced crops and the favourable soil properties too.

  • Does the feeding frequency influence the growth performance of European perch juveniles (Perca fluviatilis) during intensive rearing?
    123-128
    Views:
    120

    The European perch (Perca fluviatilis) is a predatory fish species. Its aquaculture production is increasing worldwide. Feeding and the frequency of feeding are important elements of intensive fish rearing. The aim of our experiment was to examine the optimal distribution of the amount of feed, at the same feed rations. The experiment lasted 42 days. Three treatments were applied in 4–4 replications. The first treatment was feeding twice per day (T2), the second treatment was feeding three times a day (T3), and the third group was fed four times a day (T4). 10 European perch juveniles were stocked per tank, with an individual mean body weight of 3.93 ± 0.06 g at the start of the experiment. The survival rate (S%) was above 90% for all treatments. The T2 treatments produced the most favourable harvest weight (13.96 ± 0.14 g) and specific growth rate (SGR = 3.08 ± 0.01% day-1), but no significant differences were observed between groups. In terms of feed conversion ratio, the best result was obtained by (T3) (FCR =1.06 ± 0.18 g g-1), but no significant difference was found for this indicator neither. The results of the trial indicate that the feeding frequency does not influence the production parameters.

  • Comparision of growth of mature all-female and mixed-sex Common carp (Cyprinus carpio L.) stocks in RAS
    65-68
    Views:
    422

    The common carp (Cyprinus carpio L.) is the most important fish species in Hungary, it is more than 70% of the total Hungarian fish production. The common carp production is important not only just in Hungary but in Middle-East Europe, as well as Southeast Asia. Majority of the production comes from fishpond culture. If the production sector wants to meet the increasing customer demands, there is need to intensify research on the intensive fish production opportunities for example all-female common carp technologies. The all-female technology is one of a genom-manipulation technology. Its production showed better growth rate than mixed-sex population in pond culture. Our experiment combined the recirculation aquaculture system (RAS) and the all-female common carp stocks intensification technologies. The reason for the experiment, is that there are no result about the growth of all-female common carp growth in RAS.

    The experiment used the „Tatai grey scale type” common carp stocks. We propagated two all-female stocks (T2 and T3) and a control group (TK). Due to technological characteristics of RAS, the water quality parameters were the same for all treatments and corresponded to the technological tolerance of common carp.

    The experimental period was from July 10, 2019 – November 20, 2019. Result of growth performance showed that the growth of mixed-sex stock was significantly higher than all-female stocks; (Control=3692.0±590.5g, T2=3438.8±415.4g, T3=3294.1±659.1g). Feed conversation ratio (Control=1.3±0.1 T2=1.5±0.2 T3=1.6±0.5) and SGR% (Control=0.8±0.0 T2=0.7±0.1 T3=0.7±0.1) were similar.

    By the results it can be said the all-female common carp technology has neither advantages nor disadvantages compared to the mixed-sex stock. The all-female technology can be beneficial if the consumers need female common carps. It is worth continuing the experiment and examine how the stocks will perform above 3kg body weight.

  • Investigation of the decomposition and leaching dynamics of Salix, Populus and mixed leaves in the area of Lake Balaton and Kis-Balaton Wetland
    119-124
    Views:
    184

    In lakes and wetlands, leaf litter input from the coastal vegetation represents a major nutrient load and plays a basic structural and functional role in several ecosystems. In Hungary, at the banks of lakes and wetlands, Salix and Populus trees are the most common species. In an experiment in Lake Balaton and Kis-Balaton Wetland between 16 November 2017 to and 3 June 2018, the decomposition rates and leaching dynamics of Salix, Populus and mixed leaves (50% Salix and 50% Populus) were investigated. Total nitrogen and phosphorus content of biomass samples were measured at the beginning and end of the experiment for the leaching dynamics experiment. We found that litter mass losses (Salix, Populus and mixed leaves) were not significantly different between the two mesh size litterbags and between Lake Balaton and Kis-Balaton Wetland. Different amounts of the total nitrogen and phosphorus leaching from Salix, Populus and mixed leaves were detected. The total nitrogen contents of the plant samples were around 8-18% at the end of the investigated period. Slightly higher values were measured compared to phosphorous (27-29%).

  • Allelopathic effect of invasive plants (Eriochloa villosa, Asclepias syriaca, Fallopia x bohemica, Solidago gigantea) on seed germination
    179-182
    Views:
    257

    The aim of this study was to determine the allelopathic potential of invasive species woolly cupgrass (Eriochloa villosa), common milkweed (Asclepias syriaca), bohemian knotweed (Fallopia x bohemica), and giant goldenrod (Solidago gigantea Ait.) on germination crop (Lepidium sativum L.). Experiments were conducted under laboratory conditions to determine effect of water extracts in petri dish bioassay. Water extracts from fresh biomass (leaves and stem) of invasive weeds in concentrations of 4 and 8 g/100 ml were investigated. All invasive plants showed allelopathic effect on germination. In giant goldenrod stem water extract experiment, allelopathic effect was less pronounced.

    The cress germination was greatly suppressed with the woolly cupgrass, common milkweed and the giant goldenrod. The experiment showed that the seed germination depended on the concentrations and the plant material used (leaves and stem).

  • Managerial Questions of Human Resource Management in Agriculture
    45-54
    Views:
    87

    Human resource management has many charasteristics in the field of agriculture, which should be taken into consideration from the point of view of management. Becoming a farmer is a result of a socializational process, in which tradition has a determining role. The ratio of unqualified labour in agriculture is high, compared to other sectors, and the situation is similar considering age. The number of employees is continuously decreasing; and this kind of work is determined by seasonality. Fluctuation is high, and methods for evaluating production are not well accepted. Managerial expectations changed considering labour. According to experimental results, the importance of qualification has decreased, while suiting a specific job and its duties has become more important.

  • Customer Relationship Systems and Business Models
    99-106
    Views:
    99

    The object of this study is a comprehensive review of customer relationship management (CRM) systems applied increasingly in several fields of economy. The CRM is not merely a subsequent software technology and application in the field of Business Intelligence, but rather a novel, comprehensive customer-centric approach to an organization’s philosophy in dealing with its customer for the sake of realization of short- and long-range business target contrary to the traditionally widespread productcentric approach. The object of the study, following a short
    synopsis of the theoretical and practical aspects of the CRM systems, is to analyse the range of the actual and potential users and to survey the CRM market. It will be analysed the scope of CRM supported business activities and processes, the terms and possible methods of launching and will be outlined a feasible model, too. The aim of conspectus of different CRM strategies (layers) is to reveal the urging need of turning approach in the field of management.

  • Random regression models for genetic evaluation of performance of the Hungarian show-jumping horse population
    87-91
    Views:
    125

    The aim of the study was to estimate genetic parameters for show-jumping competition performance using random regression model. Show-jumping competition results collected between 1996 and 2009 were analyzed. The database contained 272 951 starts of 8020 horses. Identity number and gender of the horse, rider, competition date, the level of the competition and placing were recorded in the database. Competition levels were categorized into five groups. Weighted – competition level used – square root transformed placing was used to measure performance of horses. The random regression model included fixed effects for gender, year and place of competition, and random effects for rider, animal and permanent environment.

    Later performance of show-jumping horses measured with weighted square root ranks is less influenced by rider and permanent environmental effects than performance at the beginning of a horse’s sporting career. Heritability increased continuously from 6.3 years of age (2296 age in days), values were in the range of 0.07 and 0.37. Higher heritability was found in later ages. Weak genetic and phenotypic correlation was found between the early 4–5–6 years of age and older (7, 8, 8+) age classes. From 8.5 years of age (3132 days old) there were strong genetic and phenotypic correlations between neighboring age groups. For the same age classes moderate and strong genetic and phenotypic correlation was found. Genetic correlation between 13.5 years of age and older horses was very strong.

  • Survival analysis of sow longevity and lifetime reproductive performance – Review
    75-80
    Views:
    254

    Sow longevity plays an important role in economically efficient piglet production. Improving sow longevity results increase in the productivity and profitability of a sow herd. Longevity is a complex trait with many factors that can contribute to a sow having a long and productive life. Not only the sow’s genetics, but also nutrition, environment and the management policies are important. In addition, the removal of non-productive sows along with the introduction of replacement gilts is an essential part of maintaining herd productivity at a constantly high level. The objective of this paper was to summarize the current knowledge about the sow longevity and lifetime performance values, as well as, discusses the survival analysis methods for sow longevity traits. This method can estimate the hazard rate indicating proportional risk of sows being culled at any given time, in addition, it is able to investigate the effects of different factors on longevity. Identifying factors that influence the longevity could assist many commercial pig producers in becoming more efficient.

  • Some population genetics parameters of the present Hungarian Hucul Horse population
    15-22
    Views:
    150

    We examined the Hungarian population of the Hucul horse breed, under genetic protection, based on population genetic indicators until the year 2014 included. The evaluation was performed using the Endog programme based on the following indicators: inbreeding coefficient, average relatedness, the maximum number of generations, the number of full generations traced and offspring number. Our findings were as follows: the average inbreeding coefficient of the total population was 5.99%, average relatedness was 11.82%, the maximum number of generations was, on the average, 16.04%, and the number of full generations traced with reference to the whole population was 4.15% on the average. 40% of the whole population (723 individuals) did not have any offspring; 42% (759 individuals) attained an offspring of 1 or 2, while 3.4% (88 individuals) had a surviving offspring of 3. The highest offspring number according to the national database (92) was attained by one stallion.

  • Study of factors controlling the amount of 0.01 M CaCl2 extractable Norg fraction
    437-449
    Views:
    181
    The use of new methods describing the “readily available” nutrient content of the soil is spreading on a global scale. The 0.01 M CaCl2 extractant is a dilute salt solution in which the easily soluble inorganic (nitrate-N and ammonium-N) and organic N fractions, P, K and micronutrients are also measurable. The 0.01 M CaCl2 has been tested in the University of Debrecen, Institute of Agricultural Chemistry and Soil Sciences since the 90’s. The results of the researches related to organic N fraction, performed in the last decades, and the results of the present study (originating from the long-term experiment of Karcag, 2007–2009) can be concluded as follows:
    The measurement of easily soluble and oxidizable organic nitrogen (Norg), besides inorganic fractions, could improve the nutrient management.
    The amount of the Norg fraction is determined by the soil conditions, therefore it is considered to be a site-specific parameter.
    Management practices and cropyear affect the amount of Norg as well. The present research confirmed that, the effect of fertilization on the amount of Norg can be explained by the changing of the yield (related to total biomass production), while the effect of cropyear is related to the differences in mineralization circumstances and yield as well.
    The measurement of the Norg fraction is increases the accuracy of N-supply, therefore it could prevent the environmentally harmful excess N application as well.