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  • The Presentation of Debrecen University’s Solar Energy Power Plant
    259-263
    Views:
    73

    Energy plays an important role in everyday life and in the economy. The use of fossil energy sources greatly damages the environment. Besides this, the quantity of these energy sources is limited. Therefore, it is important to increase the share of renewable energy sources (solar, wind, water, biomass) in energy generation. Huge amounts of energy (1150-1300 kWh/m2) arrive at the earth from the sun, which utilized in passive and active ways. One of the active applications is photovoltaic current production, in the course of which electricity is produced directly with PV-Panels. This can be fed into the grid.

  • The action of bed-slope the fish community’s composition of the watercorses on the Zagyva-Tarna watersystem
    45-53
    Views:
    57

    Between 2003 and 2005 faunistic survey was completed in the sections of the low- and highland watercourses of the water-regime of the Zagyva and Tarna rivers. On the basis of bed-slope, dominance and frequency of the fish species the following sections can be divided in the examined streams:
    1./ Upper-chub-zone: the bed-slope is above 15 m/km. The typical species of this zone – the frequency of these is more then 50%, the dominance is more than 5% – is the Barbatula barbatula, but in the case of bigger streams Leuciscus cephalus is also characteristic.
    2./ Middle-chub-zone: the bed-slope is between 5-15 m/km. The typical fishspecies–besides the Barbatula barbatula and Leuciscus cephalus – is the Gobio gobio.
    3./ Down-chub-zone: in the case of larger watercourses (Zagyva and Tarna rivers) the bed-slope is 1,2-5 m/km, at smaller streamlets it is 1,7-5m/km. The typical fishspecies–besides the 3 above mentioned species–are the Cobitis elongatoides, the Alburnus alburnus and in the watersystem of Tarna the Alburnoides bipunctatus.
    4./ Top-perch-zone: the bed-slope is 0,3-1,2 m/km, or at smaller streamlets it is 0,3-1,7 m/km. The typical fishspecies–besidestheCobitis elongatoides, the Alburnus alburnus and the Alburnoides bipunctatus - are the Rutilus rutilus, the Gobio albipinnatus ant the Rhodeus sericeus.

  • The effect of different fat content fish feed on the production parameters and meat quality of the hybrid striped bass
    33-37
    Views:
    160

    The interspecific ’hybrid striped bass’ is the result of cross breeding. Their offspring have got good chances of growth and tolerate extreme water temperatures and the content of dissolute oxygen more than their parents. Furthermore, they are more resistant to diseases. Therefore, the hybrid is perfectly suitable for intensive fishery production.

    Our experiment lasted for seven weeks. We analysed the indices of growth and production of the hybrid as the consequence of nurturing them with two feeds of high nutritive value during this period. We examined the content of fat and of fatty acids in the flesh of these fish. There were no considerable differences in terms of weight gain, feed conversion ratio and uneven growth between the two groups, while survival was less likely among the the fish which had consumed more fat. We demonstrated, examining the flesh of the individuals which had consumed feed containing lower fat content, that it was fattier and contained more dry matter than those that had been fed of higher fat content. Besides, the content of omega-3 and omega-6 fatty acids was higher in the fish that had consumed less lipids.

  • Amelioration and arable land-use possibilities of Solonetz soils in the Trans-Tisza region of Hungary
    107-117
    Views:
    170

    Salt affected soils cover about 1 million hectares in Hungary. This paper is based on the research results obtained at the Karcag-puszta long-term experimental site, where, depending on the catena, crusty (A horizon=0–7 cm), medium (A hor.=8– 20 cm) and deep (A hor.>20 cm) subtypes of the Meadow Solonetz soil could be found. The chemical reclamation was made specifically for the given site. Lime was applied on the soils with neutral or slightly acidic top layer, while on the soils with alkaline top layer, gypsum was applied. As regards internal drainage, a tube system with an average depth of 1 m and 5, 10 and 15 m drain spacing was constructed. Decreasing salt and sodium content could be measured both in drained and non-drained soils. The advantage of drainage was that the leachingout extended to the whole layer above the drain pipes, while without drainage, the Na ions exchanged from the upper layers still accumulated at a depth of 60– 100 cm. In the first two decades, the groundwater level was deeper and leaching was the dominant process. Since 2004, due to the frequently high groundwater level, the leaching and deepening of the fertile top layer has been slower.

  • Changes in the Quality Parameters of Wheat Samples of 16% Moisture Content during Storage
    117-121
    Views:
    60

    We have carried out storage experiments with wheat varieties Magvas, Fatima, Mv Emma and Mv Pálma from the 2001 growth year. During the first half of the experiments quality parameters, such as changes in moisture, protein and gluten contents as well as pharinograph readings, falling numbers and sedimentation indices were analysed and tested at an average initial moisture content of 13%.
    The findings in the changes in the quality parameters of different wheat varieties with 13% moisture content as a function of storage time duration were published in an earlier paper of mine (12/04/2002).
    This paper wishes to give an account of the second part of the storage test when the moisture contents of the different varieties were raised to 16% and the changes in the quality parameters were monitored for seven weeks. The findings show that contrary to what had been experienced in the first half of the trial, there were no changes in the protein contents, pharinograph readings, water uptake or Zeleny counts and falling numbers showed decreases with each of the varieties tested.

  • Comparative analysis of soil analysing datas on different sempling-plots
    85-90
    Views:
    64

    Hibrid maize is cultivated on larger plots, therefore the sown areas of hibrid maize are heterogeneous from a pedology aspect. Heterogenity causes problems during tasseling, chemical plant protection and harvest. The heterogenity of sown areas can be compensated by fertilization which is based on soil analysis. We carried out research into change of the soil on four soil types from 1987 to 2005.
    There were no significant changes in pH, hydroiodic acidity, CaCO3-content, humus-content on meadow chernozem soil. We detected equalization of salin content in the examined soil layers. There were no significant changes in the measured values on chernozem meadow soil and solonetz meadow soil in 2005. We discoverd equalization of saline content on chernozem meadow soil, but the changes were not as obvious as the changes on meadow chernozem soil. We found salinization in the 30-60 cm soil layer on type meadow soil that may be due to water movement.

  • Microbiological preparations affecting the soil nutrient availability and growth of ryegrass in a pot experiment
    49-53
    Views:
    136

    The effects of different bacterial fertilizers and their combinations with NPK fertilizer and wheat straw were investigated on some soil properties (chemical parameters) and on the biomass production of testplant. The applied quantities of the bacterial fertilizers were the double of the recommended dose. The experiment was set up in 2013 at the Institute of Agricultural Chemistry and Soil Science, in a three replications, in a random block design. Calcareous chernozem soil; originating from Debrecen (Látókép) was used with ryegrass (Lolium perenne L.) test plant. At the end of the experiment (after 8 week) the samples of soil and plants were determined for nitrate-nitrogen, ALsoluble phosphorus and potassium content of soil, the weight of green biomass of ryegrass per pot, the dry matter and moisture content of ryegrass. Straw treatment resulted better water and available nutrient content of soil in general. Inoculation however was not improving the biomass production over the fertilizer treatment. Interrelation with the recommended dose could be further studied.

  • Microbiological quality of bulk tank raw milk from two dairy farms in Hajdú-Bihar County, Hungary
    105-112
    Views:
    290

    Two main channels have been identified to be responsible for microbiological contamination of raw milk and milk products. Firstly, contamination has occurred due to udder infection from the cow or the blood which harbours most bacteria that come in contact with the raw milk. Secondly, via external factors (may include faeces, skin, contaminated water, environment etc.) which are associated with the operation of milking. There is direct contact with the milk and/or surfaces before, during or after the milking, posing public health risk and economic decline. The aim of this study was to examine the bacteriological quality of bulk tank raw milk samples collected from two different size dairy farms (Farm 1 and Farm 2) of different housing forms (cubicle loose and deep litter) in Hajdú-Bihar County, Hungary in July, 2017. Three samples were taken from each farm, and the total plate count, coliform count, Escherichia coli count, Staphylococcus aureus count, and yeast and mould count were determined in them.

    The results clearly showed low level of all measured bacteria group load in Farm 1 samples in comparison to Farm 2 with the exception of coagulase-negative Staphylococcus (CNS) which represented high level in general, indicating significant difference (P<0.05). The mean value of total plate count in Farm 2 samples was higher (1.0 × 105 CFU/mL) than Farm 1 samples (2.8 × 104 CFU/mL). There was a significant difference (P<0.05) in mean count of coliforms in raw milk samples between Farm 1 and Farm 2. Similarly, results of E. coli were significantly different (P<0.05) with mean count of 1.44 × 102 CFU/mL and 2.02 × 103 CFU/mL for Farm 1 and Farm 2 respectively.

    Results of Staphylococcus aureus also showed significant difference (P<0.05) with mean count of 9.7 × 101 CFU/mL for Farm 1 and 6.28 × 102 CFU/mL for Farm 2. The mean of mould count recorded was 1.07 × 102 CFU/mL and 4.93 × 102 CFU/mL for Farm 1 and Farm 2 respectively. The recorded mean of yeast count was 1.68 × 103 CFU/mL and 3.41 × 103 CFU/mL for Farm 1 and Farm 2 respectively; however, both farms showed no significant difference (P>0.05) in terms of mean of mould and yeast count. Although Farm 2 produced six times lower milk quantity than Farm 1, the measured microbial parameters were high. Both farms’ microbiological numbers were higher above the permitted limit values as stated by Regulation (EC) No 853/2004, Hungarian Ministry of Health (MoH) 4/1998 (XI. 11.).

    This could be an indication of non-conformance to effective GMP, ineffective pre–milking disinfection or udder preparation, poor handling and storage practice, time and temperature abuse and inadequate Food Safety Management System Implementation. Therefore, our recommendation is as follows; establish control measures for pre- and postharvest activities involved in the milking process which would be an effective approach to reduce contamination of the raw milk by pathogenic microorganisms from these farms, strict sanitation regime and hygiene protocol be employed and applied to cows, all equipment, contact surfaces and minimize handling of the milk prior, during and after milking. This will also serve as scientific information to the producers for continual improvement in their operations.

  • The effect of water supply and crop year on the yield potential of sweet maize (Zea mays L. convar. saccharata Koern.) hybrids with different genotypes
    203-210
    Views:
    156

    The successfulness of crop production is significantly affected by not only the the average yields that provide cost effectiveness, but also the success of striving for yield safety, therefore, varieties and hybrids tolerant to environmental stress factors are worth being included into the sowing structure. Our aim was to further the decision making of producers in prepaering the right sowing structure by the evaluation of sweet maize hybrids’ tolerance to excess rainfall.
    We performed our examinations in an extremely wet year (2010) on chernozem soil on three sweet maize hybrids (GSS 8529, GSS 1477, Overland) in 12 replications. Comparing the yields of 2010 with those that can be expected under optimal rainfall conditions, we showed that the examined hybrids react to the amount of rainfall higher than their needs with yield depression. The excess rainfall tolerance of the examined hybrids is different in the case of each hybrid.

  • Allelopathic Effect of Italian Cocklebur on Sugar Beet
    74-77
    Views:
    79

    Cockleburs are noxious weeds in Hungary, where they are widespread in row crops, especially in maize, sunflower and sugarbeet. A low density population of these weeds may be harmful because of their large competitive ability, fast growth in early phenological stages, allelopathy, and persistant sprouting.
    Allelopathy of Xanthium italicum Mor. was examined during the growing season in 2004. Root and shoot samples were collected at 4 or 5 leaves stage (in the end of May and in the beginning of June) and before flowering (in the beginning of July) before and after rain. Extracts were made in tap water. The test plant was Beta vulgaris L.; its germination, root and shoot growth were evaluated at the 6th and 10th days after treatment.
    Most of extracts inhibited the germination of sugar beet. In these experiments the phenological stage of the donor plant determined slightly the effectiveness of the extracts on sugar beet. Generally, significant differences existed between treatments only in cases of concentrated extracts.
    Rainfall can modify the inhibitory effect of extracts (especially shoot extracts). Shoot extracts of young plants inhibited stronger germination and growth after rain than before rain. Density of cockleburs influenced the effect of extracts, as well. Generally, differences between the efficacy of extracts was larger after rain.
    The results supported the hypothesis that the phenological stage and some environmental factors can modify allelopathy of cockleburs.

  • Product orientated sewage sludge composting technologies in the practice of AKSD Ltd.
    33-36
    Views:
    104

    In recent years the regulations of the EU unambiguously determine that the biodegradable wastes should be used for biogas production or composting. The direct use of sewage sludge in agriculture is limited by its hazardous microelement content, but it can be used effectively in composting. The limitation parameters can be extinguished with correct compost-mixture and technology variants. The exact determination of the technologies and mixtures result a stable, constant quality product. The compost, as a classified product, is friable structured. The end-product is a
    homogeneous mould with good water capacity, does not contain any weed seeds and pathogenic organisms. The compost does not have a acidify effect on the soil. It is an effective fertilizer thanks to its macro and microelement content.

  • The effect of the preparation method on the physical and chemical characteristics of propolis tinctures
    163-168
    Views:
    225

    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.

  • Review on the fatty acid profile and free fatty acid of common carp (Cyprinus carpio)
    99-105
    Views:
    83

    Carp or ponty in Hungarian, is considered commercial freshwater fish, which is an adaptable species in both wild and cultured conditions. Carp has high nutritional value content, favorable taste, it is rich in protein, and low in saturated fat. The nutritional content in fish is composed of many chemical constituents and influenced by many factors. One of the components that its content may be different due to internal and external factors is fatty acids, which may vary depending on endogenous and exogenous factors. The endogenous or internal factors include the genetic, size, sexual maturity, and life cycle phase. While microclimate, water quality, quality of food or diet habit, and the amount of available food or starvation are considered as exogenous or environmental factors. Freshwater fish has the ability to convert essential fatty acid into long chain polyunsaturated fatty acid like AA, EPA, and DHA. Most results showed that palmitic acid and oleic acid were the dominant SFA and MUFA in carp both for wild and farmed carp in all seasons. The PUFA for wild carp was mainly dominated by DHA, while on farmed carp by LA. It confirmed that high LA content in farmed carp was related to the diet habit. The amount of lipid and FA were changed in line with the season. Even the statistical analysis showed no significant difference, but some studies showed a contrasting result. Moreover, most obtained results acknowledged that FA tends to decrease during the spawning period. The amount and composition of FA were affected by the total lipid content. The lipid must be broken down into simpler compounds such as FA or FFA for the metabolism of fish. The result of metabolism then transported into the utilising tissue and used as energy.

  • Environmental Consequences of Efficient Use of Nitrogen Fertilizers
    41-46
    Views:
    74

    Nitrogen fertilizer represents major economic burden. For this reason, although the efficiency of nitrogen utilization varies highly, its actual use generally remains at low levels; these averaging between 25 and 50%. We set up an experiment at the Oradea Research Station, using 15N labeled fertilizers, in order to investigate the possibility of increasing N fertilizer efficiency in winter wheat under irrigation conditions.
    Fertilizers labeled with 15N allows us to individually determine its effect on yield formation, as well as the use efficiency of N from fertilizer following application rate and time. The amount of N derived from fertilizer as determined in straw and grain yield is high. When the labeled fertilizer is applied at tillering time, the values of this indicator rise when higher N levels we applied.
    In separate experiments, we investigated a series of aspects connected to chemical fertilizer regarding the determination of the type of fertilizer, optimum time and rates of application; all these as a function of the special pedoclimatic conditions.
    The results obtained in the field show that the effectiveness of N utilization in wheat is most variable and generally low, often ranging between 25 and 33%, owing to N loss within the system through leaching and NH3 volatilization.
    A readily achievable increase in efficiency of 5 percentage points would result in considerable savings, and can be brought about by reducing nitrogen losses. The added benefits to the environment in terms of reduced ground/water contamination and lowered nitrous oxide (N20) emissions would also be substantial.
    The figures for N fertilizer use efficiency (% N range from 35.5 to 72.6, the highest value being recorded with an N application of 120 kg/ha at tillering, when the previous crop was sunflower).
    INTRODUCTION