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The effect of dissolved oxygen on common carp (Cyprinus carpio) and basil (Ocimum basilicum) in the aquaponics system
89-96Views:1060Aquaponics 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. -
From the Concept of Sustainable Development to the Subsidies of Agricultural Environmental Management
354-361Views:185The most important aim of the study is to introduce the theoretical background of my PhD dissertation – agricultural environmental management –, in order to help the scientific foundations for my dissertation, which is in progress. For this reason I will try to clarify and systematize facts found in the special literature according to my own thoughts, from a new aspect.
In my study, I therefore attempt to introduce the theoretical background of sustainable development as pertains to the subsidies of agricultural environmental management (National Agricultural Environmental Management Program, National Regional Development Plan, agricultural environmental management measures). Having clarified the concepts I place sustainable development in the economic theories directed to the treatment of environmental problems, introduce where subsidies are within the environmental regulation implements and I dwell on to the institutional questions in the explanation. I then study questions of sustainable agricultural economics. Accession to the European Union has to be considered as one of the most important concrete motivities of domestically coming into prominence of agricultural environmental subsidies therefore I think it is important to study how the problematic of sustainable development, sustainable agricultural development and agricultural environment protection worked out in the EU. Finally I survey the main characteristics of domestic agricultural environment management programs fitting into the theories explained above, how the program adjusts to the theories of sustainable development and sustainable agricultural development.
In the dissertation I begin with sustainable development as the broadest theoretical background, then I survey a narrower category, the theories of sustainable agricultural development and how concrete agricultural environmental programs fit into the studied theoretical relations. -
The character of the Bódva by the composition of the fishassociations
37-44Views:302The Bódva is one of our rivers that flow outside the Hungarian borders and arrive to the country across the frontier.The Bódva is approximately 110 kilometres long, its upper course is mountaneous- like in its springfield in Slovakia and it reaches the Sajó by flowing among the lower hilly region. The river wall is ravine-like in more places, the river itself is devious, and the water basin is rather variable as in the underlay muddy segments and heavily shingly beds can also be found.
By its fish fauna and physico-chemical characteristics, the Bódva is such aliving water that-after Borne and others (Nowicki, Thienemann) river zone system- can be regarded as an almost uniform typical Barbel zone.
According to our research program (2001-2005) and literature resources we estimated the fish fauna of the Bódva on both the Slovakian and Hungarian course. From some four decades to the wide ecofaunistic examinations of the near past we surveyed the quondam and present fish species of the Bódva River. According to our survey some 40 species compose the recent fish fauna of this river.
In the fish fauna of the Bódva those fish species that presently own a tight ecospectrum, sensitive to the changes of the environment thus so called indicator species, can also be found just like the less sensitive, invasive, aggressively reproducing species. By examining the changes in the fishfauna, the complex of those biogen and abiogen processes that affect the river can be indicated well. It can be stated that the fishfauna of the Bódva is rather rich with a countrywide measure also, and maintain a lot of rare, regressive protected and worth while protection species.
In the last period of the construction, the racial and quantitive composition of the fishfauna of the upper course of the Bódva has changed significantly. Certain species (in the Hungarian course) has vanished almost totally or at least their number declined not ably. Among the vanishing species there are not only a few substantial, protected species of the fauna (e.g. Barbus pelononnesius petényi, Leucaspius delineatus, Zingel sterber, Barbatula barbatula), but the number of the once mass species also decreased appreciably (e.g. Rhodeus sericeus, Alburnoides bipunctatus, Cobitis elongatoides). With the above mentioned changes the number of other animals also decreased in the course that we examined (e.g. mussels, crabs). We examine the cause of these changes in the pollution of the river and according to that in the decrease of the food source and the negative changes of the physico-chemical parameters of the water. -
The effect of increasing compost rates on the yield and nutrient content of ryegrass (Lolium perenne L.)
127-134Views:290Satisfaction of the increasing needs of humanity causes large environmental load. To provide a livable environment for future generations we have to satisfy our needs with the use of sustainable management. This is one of the biggest challenges of nowadays.
The amount of wastes emitted in increasing volume can be decreased by the recycling of them. The disposal of waste materials formed in the public spaces of cities and during the processing of agricultural row materials and by-products in landfills is inconceivable, so they must be recycled.
These materials mostly with organic compounds could be the primary substrates of composts. Completed with suitable additives, and applied appropriate treating technology, composts are capable to supply horticultural plants with nutrients. Composting wastes and byproducts not just decreases the amounts of deposited waste materials, but increases the nutrient (macro- and micronutrients) content of soils, so this is an environmentally friendly and alternative way of nutrient management of plants. -
Biofuel production and its quality standards
137-141Views:340The increasing consumption due to the decreasing amount of fossile energy resources, as well as the increasing fuel prices and living standard will justify the better utilisation of the opportunities lying in biofuel production. Certain countries produce biofuels for their own use or they even export them. However, there are countries which have not decided which feedstock and technology to use. Biofuel – mainly biodiesel and bioethanol – use greatly contributes to environmental protection, decreased CO2 emission and reduced greenhouse effect.
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Chestnut tree: an appropriate choich for rural developement in Europe (review)
55-59Views:386In chestnut plantations or in associations many pathogens and pests can be found. They are causing more than a hundred year problem in chestnut protection, for example the blight fungus Cryphonectria parasitica. Lot of breeders hybridized the Castanea sativa and Castanea dentata with the tolerant asian species. Nowadays the presence of Dryocosmus kuriphilus seems to be the main risk. However, there are more and more chestnut plantations in Europe because of the extensive growth of needs. The food industry produces many products from chestnut, but the wood industry also use it more and more. In most of European countries the chestnut stands represent landscape aesthetics and touristic value, but probably the number of farmers inquiring the plantation will be increase in Hungary.
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Microbiological and Chemical Characterization of Different Composts
106-111Views:160Composting of agricultural waste is considered particularly important from the point-of-view of environmental protection. Degradation of organic substance results in a significant reduction of waste volume.
The end product of the composting process, mature compost, can be used as soil coverage against excess loss of wastes, for mulching, for organic manure etc. The problem of composting has come into limelight in environmental studies and in agriculture.
The quality of the mature compost is determined by physical, chemical and biological parameters of the composting process which, in turn, depend on initial composition of the raw materials, the technology, e.g. regular mixing and moistening and on environmental factors. Quality is the key question in compost use.
We studied the composting process in compost windrows of different raw material composition. We measured temperature, humidity content, pH, organic substance content, nitrogen and carbon content.
We counted the number of bacteria, microscopic fungy, ammonifying and cellulose decomposing microorganisms. We directed the composting process with turning weekly (to provide oxygen) and watering (to provide humidity content 40-60%).
We set up windrows of 1 m3 volume from dry plant substances (cornstalk, pea straw, tomato stalk and crop, weeds) and cow manure not older than 1 week. The cow manure was used at ratios of 0%, 35%, 50%, 65% and 100%, respectively.
We measured changes in compost temperature relationship with outside temperature until they were almoust the same. Humidity was 40-60% in most cases.
At the beginning of the process, pH was slightly acidic-neutral; it later becomes neutral-slightly alkaline (pH: 6.93-8.02) as ammonia is liberated from proteins.
At the end of the process, pH decreased again, due to humification.
Organic substance content decreased as microorganisms mineralized them. Organic carbon content decreased gradually due to microorganisms used it as an energy.
Total nitrogen content increased until middle of july and decreased gradually until than.
The carbon/nitrogen rate were higher in the beginning, it decreased until july-august and increased by smaller degree until end of the process.
The number of bacteria was higher in the first three weeks and between june-september. The number of cellulose degrading bacteria was the highest in the first three month, the number of ammonifying bacteria was the highest from the end of may until sepember.
The number of microscopic fungy was significant in the second part of process, after july. -
Comparison of Reproductive Performance of the Roe Deer (Capreolus capreolus, L.) Among Different Regions
41-46Views:221The potential and actual number of offspring of roe deer and the difference between these figures (prenatal and postnatal loss) significantly vary in each population yearly. The objective of this study is to examine the potential and actual number of offspring, the number of losses, and to find a link between the most important biological characteristics of does (body weight – BW, condition – KFI) and the number of raised offspring on four territories on the Great Hungarian Plain.
Where the number of corpora lutea (CL) is the highest, there the losses are the highest as well, and the number of raised offspring is the lowest (region I.). Here, the rearing loss is double that of the weakest territory (region IV.). Rearing losses can be associated with the fenotype of does (BW, KFI) but environmental factors also have determinative importance. Where the number of twin-calving does was the highest, I found four times more does without a fawn than where the number of twin-calving does was the lowest. The nursing success was the best (the losses were lowest) in the region where the potential offspring (number of CL) was also the lowest, but the coverage of the habitat and the proportion of forests were largest. The food supply for the animals in autumn and winter are not enough, the structure of the habitat has to be improved as well, so that it might become adequate for game protection in extreme weather conditions.
The results have to be considered as preliminary ones. It is essential to continue and extend the research to increase the reliability of the results. -
Plant growth analysis of wheat populations in a long-term field-experiment
147-151Views:415The experiments were conducted as part of the long-term trial adjusted, in triculture (pea-wheat-corn) and biculture (wheat-corn), at three nutrition levels, with the use of one crop protection technologie (conventional) at the Látókép Research Site of the Centre of Agricultural Scienses, University of Debrecen, on a chernozem soil. The wheat variety used in the long-term trial was GK Csillag, which was sown at 5,8 million germs/ha.
The effect of pre-crops and nutrient-supply levels on some growth-parameters (LAI, HI, LAD), just as SPAD-values and yield amounts of winter wheat has been investigated in this experiment. We tried to find out the extent of relationship between the different parameters, so we determined the relationships between different nutrient-supply levels, yield amounts, LAI- SPAD- and LAD-values – measured in the crop-year of 2010–2011 in different crop rotation systems – by using correlation analysis. It has been stated both in case of bi- and tri-culture crop-rotation systems that different fertilizer dosages had significantly affected the leaf area index dynamics and its maximal value, and that increasing N+PK fertilization has
significantly increased the duration of leaves, as well. The highest SPAD-values were measured during the flowering and grain filling stages. However, we haven’t revealed significant differences between all fertilizer treatments. In case of the bi-culture crop-rotation system harvest index values showed an increasing tendency parallel to the increasing nutrient-supply levels, while in case of the tri-culture system this tendency was rather decreasing. However, these differences were
not significant. Parallel to the increasing fertilizer dosages yield results were increased in a significant extent. At the same nutrient supply-levels 2088–4615 kg ha-1 higher yields were measured in the tri-culture than in the bi-culture system. The correlation analyses have confirmed that all of the investigated parameters (yield amount, LAI, SPAD, LAD) had almost in all cases close positive correlation to the nutrient-supply level and the yield amount in both crop-rotation systems. These results have confirmed that the leaf area, the leaf duration, the SPAD-values and the fertilization have altogether resulted in the production of maximum grain yields. -
Contributions to the 2014 and 2015 flight pattern and damages of Carpomyia schineri Loew.
96-99Views:233The fly Carpomyia schineri Loew is a pest of the berries of the feral Rosa canina group but is can also be found in the berries of grown rose cultivars. The larva damages the flesh of the berry, several larvae can develop inside a single berry. It can decrease the quantity and ascorbic acid content of the tea and jam, which are important human ascorbic acid sources during winter. At the same time in trapping experiments the adult can be confounded with adults of the walnut husk fly (Rhagoletis completa Cresson). In collections of berries at several sites in Hungary damage levels ranged from 0.88% to 65.08 %. Based on these damage levels we had the impression that the yellow sticky traps CSALOMON® PALz or PALs baited with the synthetic Rhagoletis lure caught moderate numbers of adults and were not satisfactory for detection, consequently improving trapping methods is necessary in the future.
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The potential of biological control on invasive weed species
73-75Views:323Sorghum halepense is one of the invasive species in Europe. This study was made to identify the morphology of fungi on invasive weed species samples on the roots of Sorghum halepense. The samples were collected in the region of Debrecen. The experiment was conducted under laboratory conditions to determine the microscopic form of fungi. The samples were put on PDA and for identification of fungi is based on the morphological characteristics of the features and colonies of conidia that were developed in Petri dishes.
The examination of the culture revealed that the fungus from the root of Sorghum halepense was Aspergillus niger. Pathogenicity and the relationship between the fungus and Sorghum halepense are still uncertain so in the future pathogenicity tests and re-isolations from plants are very important steps.
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Valuation of the National Agricultural Environmental Management Project’s Extensive Grassland Farming Target Project in Two Counties
20-25Views:201The National Agricultural Environmental Management Project’s (NAEMP) extensive grassland farming project is aimed at extensive cultivation on of nearly 1.1 million hectares of grassland, and at improving the state of grasslands with nature- and environment protecting methods. By using the 2002 data (the NAEMP’s first year’s data), I came to the following conclusions: Within the Extensive grassland farming project, a state subsidy was applied for on 8.94% of Hungary’s total grasslands. In Szabolcs-Szatmár-Bereg and Hajdú-Bihar counties, applied for state subsidies covered 12% of the grassland of the counties.10.45% of the projects arrived from the county of Szabolcs-Szatmár-Bereg, and 28.56% from the county of Hajdú-Bihar. In Szabolcs-Szatmár-Bereg, the support was 37.7% of the total subsidy, while in Hajdú-Bihar, it was 37.1%, unlike nationwide, which was 30.1%.The intensity of the applications is respectively 1.7 and 2.5 times more than the National (1.24) value.
In my view, in some fields, which are not between nature protected areas you’d better consider permitting intensive cultivation, simultaneously with grazing, with the observation of nature- and environmental regulations. -
Agronomical and Economic Evaluation of Different Soil Cultivation Systems
17-22Views:217In the interest of profitable plant production and environmental protection we have to make an effort to protect and improve the productivity of our soils while moderating production limiting factors. Due to different soil cultivation methods, the quantity of yield and required expenses also differ.
We examined the production costs in four different production technology systems. Overall, it can be said that farming standards are good, since cost prices were low (2001: 14-15 HUF/kg, 2002: 15-21 HUF/kg, 2003: 39-49 HUF/kg) in the case of all main products per 1 kg. Cost prices were lowest in the case of direct sowing, probably due to low machinery costs.
All economic indicators have to be compared when choosing the most suitable production technology in a specific farming environment. -
The hydric stress influence on quantityand quality of the maize yield in the Crisurilor Plainconditions
21-27Views:267The paper is based on the researches carried out in an experiment placed on the preluvosoil from Agricultural Research and Development Station Oradea, Crisurilor Plain during 2008–2011in the following variants: V1=Irrigated, without irrigation suspending; V2=Irrigated, irrigation suspending in May; V3=Irrigated, irrigation suspending in June; V4=Irrigated, irrigation suspending in July; V5=Irrigated, irrigation suspending in August; V6=Unirrigated. The hybrid used: Fundulea 376. In the variant with optimum irrigation, water reserve on 0–75 cm depth was maintained between easily available water content and field capacity. Pedological drought was determined every year and the irrigation was also needed. The irrigation determined the increase of the total water consumption and yield gain in comparison with unirrigated variant. Irrigation suspending in different months determined the yield losses very significant statistically. The biggest protein content was registered in the variant without irrigation suspending; the values registered in the variants with irrigation suspending in May, June, July and August and in the unirrigated variant are smaller, with differences statistically assured. There was a direct link between de Martonne aridity index values and water consumption, yield and protein content and an inverse link between pedological drought and yield quantity and protein content. These are the arguments for irrigation opportunity in maize from Criurilor Plain.
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Change of soil nitrogen content in a long term fertilization experiment
39-44Views:384The most important aim of sustainable agriculture is to ensure our natural resources – such as soils – protection, which includes fertility preservation and the use of appropriate methods of cultivation.
If we want to get accurate information about the occurred changes, way and danger of changes, we should track the resupply and effect of the mineral nutrients and the removed quantity of nutrients with the harvest.
Nitrogen is an essential element for living organisms and it is present in the soil mainly in organic form. In general only a low percentage of the total nitrogen content can be used directly by plants in the soil. The mineral nitrogen is incorporate by plants into our bodies. This inorganic nitrogen is produced by the transformation of organic contents through mineralization processes and it gets into the soil by fertilization. This is how nitrogen turnover occurs when mineral forms become organic and organic forms become mineral.
The objective of this publication was to introduce – through some element s of nitrogen turnover- how changing the properties of soil in a long term fertilization experiment.
We established that the fertilization is influenced the soil pH. With the increase of fertilization levels increased the acidity of the soil, maybe it is related with the number of nitrification bacteria. The fertilization and the rotation affected to the quantity of nitrate.
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The identification of phylloquinone in cattle samples using T.L.C. method
75-78Views:159A case of hemorrhage of unknown origin was observed in cattle and liver samples were submitted for assay of Vitamin K or
possible cuomarol. After evaluating normal and reverse phase Thin Layer Chromatography (TLC) plates and different solvents,
reverse phase TLC plate with indicator and methylene chloride:methanol 70:30 were chosen for direct method of detection and
indication of Vitamin K.Gass Chromatography and Densitometry were used to quantitate the Vitamin K present in liver samples and
confirmation of Vitamin K was done by Mass Spectroscopy. -
Assessment of Environmental Susceptibility/Vulnerability of Soils
62-74Views:247Soils represent a considerable part of the natural resources of Hungary. Consequently, rational land use and proper soil management – to guarantee normal soil functions – are important elements of sustainable (agricultural) development, having special importance both in the national economy and in environment protection.
The main soil functions in the biosphere are as follows: conditionally renewable natural resource; reactor, transformer and integrator of the combined influences of other natural resources (solar radiation, atmosphere, surface and subsurface waters, biological resources), place of „sphere-interactions”; medium for biomass production, primary food-source of the biosphere; storage of heat, water and plant nutrients; natural filter and detoxication system, which may prevent the deeper geological formations and the subsurface waters from various pollutants; high capacity buffer medium, which may prevent or moderate the unfavourable consequences of various environmental stresses; significant gene-reservoir, an important element of biodiversity.
Society utilizes these functions in different ways (rate, method, efficiency) throughout history, depending on the given natural conditions and socio-economic circumstances. In many cases the character of the particular functions was not properly taken into consideration during the utilization of soil resources, and the misguided management resulted in their over-exploitation, decreasing efficiency of one or more soil functions, and – over a certain limit – serious environmental deterioration.
Soil resources are threatened by the following environmental stresses:
– soil degradation processes;
– extreme moisture regime;
– nutrient stresses (deficiency or toxicity);
– environmental pollution.
Environmental stresses caused by natural factors or human activities represent an increasing ecological threat to the biosphere, as well as a socio-economic risk for sustainable development, including rational land use and soil management.
The stresses are caused by the integrated impacts of various soil properties, which are the results of soil processes (mass and energy regimes, abiotic and biotic transport and transformation and their interactions) under the combined influences of soil forming factors. Consequently, the control of soil processes is a great challenge and the main task of soil science and soil management in sustainable development.
The efficient control of these processes necessitates the following consecutive steps:
• registration of facts and consequences (information on land and soil characteristics, land use, cropping pattern, applied agrotechnics, yields, with their spatial and temporal variability);
• evaluation of potential reasons (definition and quantification of soil processes, analysis of influencing factors and their mechanisms);
• assessment of the theoretical, real, rational and economic possibilities for the control of soil processes (including their risk-assessment and impact analysis);
• elaboration of efficient technologies for the „best” control alternatives (best management practice).
Scientifically based planning and implementation of sustainable land use and rational soil management to ensure desirable soil functions, without any undesirable environmental side-effects, require adequate soil information. In the last years such data were organized into a computer-based GIS soil database in Hungary, giving opportunities for the quantification, analysis, modelling and forecasting of the studied environmental stresses and for the efficient and scientifically based prevention, elimination or reduction of environmental stresses and their unfavourable ecological and economical consequences.
Special attention was paid to the assessment of various soil degradation processes, as: (1) soil erosion by water or wind; (2) soil acidification; (3) salinization and/or alkalization; (4) physical degradation (structure destruction, compaction); (5) extreme moisture regime: drought sensitivity and waterlogging hazard; (6) biological degradation; (7) unfavourable changes in the plant nutrient regime; (8) decrease of natural buffering capacity, (9) soil (and water) pollution.
The actions against undesirable environmental stresses and their unfavourable consequences are important elements of sustainable, efficient, economically viable, socially acceptable and environmentally sound crop production and agricultural development. These are joint tasks of the state, decision makers on various levels, the land owners, the land users and – to a certain extent – of each member of the society. -
Influence of Hydrological Parameters on the Biodiversity of the BerettyóRiver I.
215-229Views:395The DIRECTIVE 2000/60/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL orders the measurement of the state of natural and artifical waters. We therefore applied environmental qualification methods, which allow inductions of the searched area in environmental management, conservation and water quality protection points of view. These methods are accepted in interdisciplinary sciences, and are in use in Hungarian and international practice. We applied the range data measured along the Berettyó River, and ratified by the remote sensing, to count hydrological-hydraulical attributes of the stream, by the framework of the Hec-Ras programme. We processed the physical, chemical and biochemical water qualifications, determined the MMCP-index (the point-system of the Hungarian macrozoobenthos taxons), and estimated the Spencer index-numbers, which were based on complex environmental qualification and bioindication. Appointed, that the different results of researches are not inconsistent. This results together the spatial analysis reveal the natural and anthroponetic specialities of the river and the landscape, which determine the environmental flavours and biodiversity. The bioindicators represent better environmental status, than the physical, chemical and biochemical parameters. The natural conservationist importance of drainage canal network of Bihari-Plain is appreciated by these facts.
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Violation prooxidative-antioxidant stability at maize shoots at different level of accumulation of cadmium and nickel
89-94Views:182Joint influence of cadmium and nickel was investigated on the feature of their accumulation by the vegetative organs of 10-days' old maize shoots. It was established that most intensively noted metals are taken in by the roots of shoots in the first 7 hours stressing influencing, while in leaves they appear only after a 7-hour long exposition. It was stated that the absorption process of the noted metals by a root system is carried by two-phase character. The indexes of inner-tissue contamination are calculated. Activating by the cadmium and nickel ions of lipid peroxidation as marker of the stressing influencing, and also was shown the proper increase of intensity of functioning of ascorbate peroxidase as the antioxidant enzyme protection of cell.
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Alternatives of microclimate control in orchards
209-212Views:387The aim of the study was to find out which of the methods used to avoid damages of late frosts would be the most effective for the fruit growing practice. We tested the antifrost irrigation method in Debrecen-Pallag. For that purpose microjet sprayers are used, which are thrifty and does not need for that purpose large containers. With the aim to secure an even distribution of water, the sprayers are distributed on three levels: above and inside of the crown as well as on the level of trunks. On a large scale, a single microjet above the crown level would be sufficient. By means of a detailed analysis served to set the optimum intervals between spraying phases: with each 15, 10, 5 and 3 minutes during half a minute. The synchronous presence of water and ice below the freezing point, the released freezing heat plus the water used much above the freezing point
(9–10 °C) altogether maintains the temperature above around 0 °C near the flowers or growing fruitlets, meanwhile, the surrounding air cools down to -8 °C. The effectiveness of the generally used antifrost would be increased substantially by the former application of cooling irrigation, which delays the blooming date. -
Practical experiences of a designing and operating a pilot aquaponic system
27-32Views:764Aquaponics is the combination of fish farming (aquaculture) and the soilless cultivation of plants (hydroponics). The aquaponics system is an artificial, recirculating ecosystem, in which bacterial processes convert the waste materials in the water used for fish rearing into plant nutrients, and therefore with the generated heat it is suitable for culturing economically valuable plants, and thus it mitigates the nutrient laden and quantity of the intensive fish producing systems’ effluent water.
The primary goal of our 12 separate unit’s aquaponics system was to gain experience. We would like to find the right plant species, which are fit for that medium, and their crop can be sold. Besides the plants, our attention focused on the fish. Two fish species were included in the experiments, the common carp and barramundi. It was difficult to create them a perfect living space, besides a constantly changing conditions temperature. Apart the above mentioned we had a problem with the number of individuals per tank, the deformity of the fish body and the too high volume of pH (we registered continuous values above 8.4). We get by carps 4.7 grams of weight gain during 15 weeks, because of the bad conditions.
The main problems at the plants are caused by aphesis and protection against sunburn. Even so we have got the multiples of field yields for each plant species. At salad has grown twice of field yields, tomatoes one and half, kohlrabi than 3.5 times more. The causes of multiple yields are the continuous balanced water and the nutrient uptake of plants. Each plant species fit for cultivating in aquaponics and their crops are delicious, chemical -free, safe and marketable. The plants should be more concentrated. After the experiment, it has been determinated that the carp is suitable for aquaponics, but greater weight gain could be achieved with optimal selection of size of rearing units.
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Essential oil extraction from herbs and their use in the food industry
59-74Views:588Essential oil extraction of wild caraway and thyme was performed using a classical (HD) and microwave hydro-distillation (MWHD) and a laboratory supercritical fluid extraction (SFE) with a carbon dioxide as solvent. Our experiments demonstrated that the extraction yield of the essential oil performed in same conditions was influenced by the location of growth area; the maximum extraction yield of 10 ml 100 g-1 caraway was obtained from dried seeds collected from Csíkmadaras. This quantity far exceeded the yield of the Újtusnád samples. In the case of wild caraway (Carum carvi L.), the extraction method influenced thecomposition of the essential oil (carvone/limonene ratio), the highest limonene content being achieved by classical hydro-distillation. In the case of thyme, this effect was not detected, the thymol/carvacrol ratio was independent from the given extraction method. The obtained thyme essential oil possesses high antimicrobial activity demonstrated by agar diffusion test. The thyme extract provides a good protection against microorganisms collected on the surface of fresh vegetables following bacterial stains: Citrobacter portucalensis, Pseudomonas hunanensis, Pseudomonas baetica, Pseudomonas parafulva, Bacillus mojavensis and Enterobacter cloacae. Protective effect was also detected on the vegetable surface of by chitosan-based edible film coating during a 6-day-long storage period at a temperature of 4 °C. The caraway essential oil used as soft cheese seasoning with a direct, dilution-free method, proved to be unsuitable because the uneven distribution and confer a strong, unpleasant taste to the product in comparison with the ground wild caraway seed-dressed cheese.
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Examination of different fungicides against Macrophomina phaseolina in laboratory conditions
65-69Views:382In Hungary, sunflower is the third most important arable crop, which has a lot of pathogenic fungi. One of these fungi is the Macrophomina phaseolina, which is a well-known fungus in all over the world, since this pathogen has more than 700 host plants. In Hungary, several host plants can be found as well. The M. phaseolina produces microsclerotia, which can survive in the soil and residues for almost 10 years. For now, there is no efficient treatment against this pathogen because of this fungus, since it is extremely resistant and cannot be destroyed easily. The only effective treatment against the fungus is genetic defence. In this study, three different fungicides were tested in vitro against the fungus. The Mirage (prochloraz) seemed to be the most effective fungicide as it completely arrested the hyphal growth. In contrast, the Amistar Xtra (azoxystrobin and ciprochonazol) has only a minor effect on the growth of M. phaseolina. Thirdly, the Retengo (pyrachlostrobin) arrested the hyhpal growth of the fungus with 71% at 100 ppm, in other words, the use of this fungicide seems promising.
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Possibilities of ecological farming in the North Great Plain Region
69-71Views:186Agriculture plays a significant role in the North Great Plain Region. Organic farming is a sustainable farming method controlled by regulations. Active environmental protection and conservation play significant roles in organic farming, along with food quality and safety, originality and the monitoring of products. Organic farming offers opportunities to create employment, social safety and high profitability. As a result of these characteristics, organic farming could become one of the most important means of developing our region in the future.
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Occurrence of woolly cupgrass (Eriochloa villosa /Thunb./ Kunth) in Hajdú-Bihar county, Hungary
119-123Views:188Woolly cupgrass (Eriochloa villosa /Thunb./ Kunth) is native to East Asia, it spreads in several parts of the World and causes difficulties in plant protection, especially in maize. Difficulties in control of Eriochloa villosa originated from several reasons: seeds continue to germinate later in the season, significant part of seeds emerges from a deep layer of the soil, and the species is less susceptible to some herbicides applied to maize than other annual grass weeds.
The first report on the occurrence of woolly cupgrass in Hungary was published in 2008, and it reported about the appearance of this species near to Gesztely village (Borsod-Abaúj-Zemplén county), however, no information has been added about spread of the weed in Hungary until now.
A significant population was discovered next to Debrecen (Hajdú-Bihar county) in summer, 2011, and then weed associations were examined in maize, sunflower and stubble-fields on several km2 in the area to estimate the Eriochloa villosa infection. The weed species was found on every maize field bordering with a ground cover of 0.5-4%. Woolly cupgrass occurred inside of the 50% of maize fields, and reached a ground cover of 76% in case of most infected area, in addition it was found in sunflower and stubble-fields.
The spread of woolly cupgrass is expected in this area, which requires the consideration of this species in the planning of weed management technologies.