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Food safety of plant origin food
161-164Views:467Expectation regarding changes related to food production, transportation, distribution and marketing have changed considerably in several regions of the world over the past decades. It is especially true for highly industrialized countries where not only the food security is important but the food safety is essential too. The concentration of production – processing – distribution involves the danger on the one hand products of unsuitable quality from point of view of nutritional physiology and the other hand ones that may contain substances harmful to human health will become widespread among consumers. We investigated the heavy metal, pesticide remains and mycotoxin content of different plant products.
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Establishing regional cultivating districts on the basis of the Kreybig practical soil mapping system
20-25Views:463With the help of this report evaluating the current situation of the region, characteristics of the development in agricultural production and regional differences can be clarified. By mapping out the regional soil, land use and climatic conditions and organizing these into a geographical information system, one can easily determine which plants are the most ideal to cultivate in that particular region. Moreover, it is a useful tool that enables us to
establish the most favorable land use structure suited to ecological demands and also helps to determine the methods of soil protection.
During our work, we chose administrative units in Szabolcs-Szatmár-Bereg County, based on the latest aspects of regional cultivation.
Our pilot areas are: the small regions of Nyíregyháza, Nyírbátor, Nagykálló, Mátészalka and Csenger.
Using the database, we separated and uncovered the soil conditions of the pilot areas: the chemical and physical properties of the soil layer which is exploited by the roots of the plants, the humus content, the nutrient supply, the thickness of the cultivated layer and the water management conditions.
We separated the districts of regional cultivation, where the basic elements of the traditional Kreybig color systems were applied (light yellow, dark yellow, light brown, dark green, blue, pink, red, gray, greenish brown, reddish purple, light purple, dark purple, light green).
By using the data collected from the pilot areas, we compiled a map database, which is suitable to illustrate the plant cultivating characteristics of the region. We made recommendations to determine the most favorable plants to cultivate in the specific region with the given meteorological and soil conditions, as well as for the shifting of crops.
Our recommendations were also illustrated in a map with a resolution of 1:25000. -
The Effect of Changes in Forest Area on the Transcarpathian Tisza River Basin
181-185Views:185Forests are unique global factors which ensure life for almost every living being on Earth. They play a major role in controlling water flows, preventing erosion and controlling the oxygen content of Earth’s atmosphere. By the end of the XXth century, it was realized that forests help to nature maintain and are vital parts of our natural environment. By the time societies realized this fact, economic and environmental effects had amplified which endanger forests. Due to their good water control and water protection abilities, and their function in climate control, mountain forests can provide a suitable environment for themselves, for their successful growth.
Forests play a major role in soil protection, especially in mountain areas where they prevent soil erosion. By converting surface waters into subsurface waters, forests help with the accumulation of subsurface waters, which are the sources of springs, rivers and streams. In the summer, they protect the soil from drying out by creating a special microclimate. They positively affect the climate of surrounding territories. -
Physiological examination on cadmium sensitvity of some maize and sunflower varieties
169-173Views:201Cadmium is one of the most dangerous heavy metals, which may cause serious problems in certain physiological processes of living organisms even in small amounts. In our work we analysed how cadmium affects some physiological parameters of different maize and sunflower hybrids. The chlorophyll contents and the morphological changes of the root were examined. We received different results in terms of the cadmium tolerance of these two plants.
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The effects of curing technology on the rheological and organoleptic features of meat products
139-142Views:191Meat products are important staple foodstuffs owing to their high protein, vitamin and mineral content. Meat plants do not only use traditional production technologies but also develop methods that preserve the nutritional value of meat or improve the texture and organoleptic features of meat products. These features play an important role in the consumer society. Consumers first meet the external features of meat and this experience influences their decisions. Our analyses compared a traditional and a new curing procedure. Besides organoleptic inspections, we analysed texture with a CT3 type Texture Analyser to obtain quantified information on the condition of meat samples in the various curing phases. We used our results to compare traditional and new curing procedures.
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The Role of Cultivation Systems in Quality Sugar Beet Production
134-138Views:609Producing sugar beet, as it is a demanding field crop, has contributed to the raising standard of plant production. It has an outstanding place among the plants that are cultivated in the intensive plant production system. Rentability of sugar manufacture is determined by the stability of yield and the quality (saccharose content) of sugar beet. In this way, the fundamental interest both of the producers and the processing industry is high yield and quality, year by year. The yield and the quality of the sugar beet are mainly determined by the plant production system, so we studied the effect of fertilization, irrigation and plant protection.
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The examination of relation between the C/N ratio and the biogas yields in the Regional Biogas Plant of Nyírbátor
63-68Views:277The Regional Biogas Plant of Nyírbátor was built by the Bátortrade Ltd. The biogas plant contains 6 mezophil and 6 thermophil fermentation tanks, because the biogas production is based on mixed compositions. The regional plant is a multifunctional system. It produces agricultural products and biogas with high methane content. The utilization of biogas is also accomplished here; gas-engines transform it to electricity and
heat-energy. The product electricity is used by the local plants, the surplus is sold.
The aim of the research is the examination of the quality and quantity of the input materials that put into the mixers and follow the seasonal, periodical and optional changes of the input materials. The analyzation of the quality and quantity data can give an answer to the optional changes of biogas production because the input materials determine the composition of the examined recipe. The C/N ratio was between 11-13, the maximal value of the biogas yield was observed by 12.35 C/N ratio. -
Determining elements of variety-specific maize production technology
157-161Views:301Our aim was to work out such new maize fertilizer methods and models which can reduce the harmful effects of fertilization, can
maintain the soil fertility and can moderate the yield fluctuation (nowadays 50-60 %).
The soil of our experimental projects was meadow soil. The soil could be characterized by high clay content and pour phosphorus and
medium potassium contents. In the last decade, out of ten years six years were dry and hot in our region. So the importance of crop-rotation
is increasing and we have to strive for using the appropriate crop rotation.
The yields of maize in monoculture crop rotation decreased by 1-3 t ha-1 in each dry year during the experiment (1983, 1990, 1992,
1993, 1994, 1995, 1998, 2000, 2003, and 2007). The most favourable forecrop of maize was wheat, medium was the biculture crop rotation
and the worst crop rotation was the monoculture.
There is a strong correlation between the sowing time and the yield of maize hybrids, but this interactive effect can be modified by the
amount and distribution of precipitation in the vegetation period. At the early sowing time, the grain moistures were 5-12 % lower compared
to the late sowing time and 4-5 % lower compared to the optimum sowing treatment.
There are great differences among the plant density of different maize hybrids. There are hybrids sensitive to higher plant density and
there are hybrids with wide and narrow optimum plant densities.
The agro-ecological optimum fertilizer dosage of hybrids with a longer season (FAO 400-500) was N 30-40 kg ha-1 higher in favourable
years as compared to early hybrids.
We can summarize our results by saying that we have to use hybrid-specific technologies in maize production. In the future, we have to
increase the level of inputs and have to apply the best appropriate hybrids and with respect to the agroecologial conditions, we can better
utilize the genetic yield potential. -
N-fertilization using „Biofert” in Sustainable Maize Production
30-33Views:548In synthetic fermentation of lysine (amino-acid) a by-product (Biofert) originates which can be characterized by 6% N-content and other ingredients (vitamins, enzymes, micro-elements etc). In small and large plot experiments Biofert was studied in different agroecological (cropyear, soil), biological (genotypes) and agrotechnical (non-irrigated and irrigated; N-splitting etc) conditions in order to obtain information about agronomic efficiency and environmental effects of its applications.
Our results proved that Biofert has the same agronomic efficiency as traditional N-fertilizers (applied in equal doses and splitting), but Biofert has economic and environmental advantages (less N-leaching in soils) for maize production. We found a special interaction between N-supply and irrigation. In maize production (irrigation) with the optimum application of nutrient- (N-fertilization, Biofert) and water- supply we could stabilize maize yields at a high level (11.0-14.0 t/ha) fairly independently of agroecological factors. When applying Biofert in autumn, NO3-N leaching was less in 100-200 cm chernozem soil-layers than for applications of traditional N-fertilizer. There were no differences between different maize genotypes concerning the agronomic efficiency of Biofert. In maize production 120-190 kg/ha N (chernozem soil) and 165 kg/ha N (meadow soil) doses of Biofert were the optimum doses in splitting applications (autumn + spring). -
The effect of copper fungicides on the rate of photosynthesis and the transpiration of hop plants
117-123Views:203The paper evaluates the effect of copper fungicide spraying on the rate of photosynthesis and transpiration of hops, the influence of spraying on the elemental copper content in the leaves and cones hop variety Agnus. Photosynthetic rate was measured by LC pro+ (infrared analyzer) in the Hop Research Institute Saaz in the field in some periods of 2008, 2009 and 2010. Dry cones and leaf samples (taken before and after application of copper fungicides) were analyzed in an accredited laboratory for elemental copper.
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Study of factors controlling the amount of 0.01 M CaCl2 extractable Norg fraction
437-449Views:332The 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. -
Preliminary results of the combined production of duckweed Spirodela polyrhiza and common carp (Cyprinus carpio) in an aquaponic system
83-89Views:423As a result of population growth, increasin amount of food is needed, and agriculture is under an increasing burden to meet these needs. Traditional agriculture is often attacked due to its environmental impact. We must find alternative, environmentally friendly ways to produce more food. Aquaponics is a closed system in which we can produce both fish and plants at the same time. Duckweed species are small, aquatic, floating plants belonging to angiosperms. It can potentially be an alternative protein source, due to its high protein content, good amino acid supply, and rapid growth. Under suitable conditions, it doubles its weight in 2–4 days, and can reach a yield of 30 t ha-1 year-1in dry matter. It forms a carpet on top of the water and can be found in slow-moving or still waters. Since they are resistant to a wide range of nutrient concentrations, they are also suitable for cleaning wastewater (such as eutrophicated lakes, sewage reservoirs, liquid manure storage). Fish feed is the primary nutrient source for aquaponic systems, which usually contains fishmeal. If duckweed can be used as an alternative for fishmeal in the feed, it could improve the sustainability of the aquaponic and aquaculture systems. In this study, the aim was to develop an optimal harvesting protocol for duckweed Spirodela polyrhiza under aquaponic conditions. In a four weeks experiments, four harvesting protocols were set up, a control where only biomass measurements were made, a 25% group where 25% of the biomass at the time of measurement was harvested, and a 50% and a 75% group where at the time of measurement 50% and 75% of the biomass was harvested. Three replicates were used per treatment. We weighed the biomass every week and removed the amount corresponding to the group. Based on the preliminary results, it can be said that more biomass was obtained in the groups with the 25% harvesting protocol and the control group.
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Examination of compost maturity using reflectance
29-34Views:626Composting is one of the most popular recycling processes for organic waste. Composting plays an important role in waste and by-product management and is becoming increasingly important in both sustainable energy management and circular economy. Composting transforms organic matter to produce a safe and stable by-product (compost) that can be applied to arable land in a similar way to fertilizer. Physical, chemical and biological methods can be used to monitor the process and to determine the maturity of the compost, as spectrometric/spectroscopic methods play an important role in the analysis of different environmental samples.
Our aim was to (1) non-destructively detect the effects of different additive ratios on the spectral properties of the composting process and the spectral data of different compost mixtures, (2) to find the wavelength ranges of the reflectance curve (inflection points) sensitive to compost maturity, (3) to determine the correlation between the inflection points and the chemical and physical parameters measured in compost by conventional methods.
The mixture of broiler and hen manure and zeolite was composted 62 days in windrow composting. In the composting experiment, the moisture content and temperature (°C) were measured every three days and compost samples were taken and in 10% destillated aquaeous suspension were measured the pH and electrical conductivity (mS cm-1). Compost samples dried to mass stability were spectrally analyzed in the wavelength range 400–1000 nm with AvaSpec 2048 spectrometer.
Based on the results, the reflectance of mature compost were smaller in the last days of composting than the reflectance values of day 0 samples, thus compost maturity can be detected spectral in the VIS-NIR wavelength range. For the tested compost prisms, the reflectance of each sampling day shows a constant slope, with a significant overlap of the reflectance curves up to 400–700 nm wavelength range, and there was a breakpoint in the 700–750 nm wavelength range which was proved by binary encoding.
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A földhasználat alakulása az ezredfordulón - egy felmérés eredményei
58-66Views:223There were no significant changes in land ownership and use in 2000, compared to the period following the compensation process. Land is mainly owned by people who do not want to use their property, so they generally turn to renting it out to others. Although farming on rented land is performed under various conditions, farms try to rent the lands of better quality. In general, examined farms would like to increase their size by tenancy or land purchase. Buying land is a good investment, considering the price increase in the future, but because of the lack of capital, tenancy remains the main form of territory increase.
Farms which rent land are in connection with a lot of owners, the land within their use is frittered away, it is in a lot of parts. Most rental contracts are written, but the ratio of oral contracts is still quite high. To reduce this ratio is one future aim. One more characteristic of the rental contracts is the dominance of a medium length period – which is acceptable for both the owner and user, but the ratio of short time contracts is still high. Land rent, on average for the examined farms, is quite balanced, it is on the level of about 16.000 HUF/hectare.
The land users mainly pay the same land rent to the owners, but in some cases, there are exceptions. Generally, land rent is a fix cost, but sometimes this cost depends on the level of the yield or the change of product price. Land rent, on average, is 16% within the production costs on the examined farms, which try to choose better and larger lands for rent. Sometimes, farmers can pay higher land rent for the unit of better land, but this is not a general tendency. It is mainly true that they pay the same land rent for the unit, regardless of land quality. Land owners can not interfere in the use of their land within the rental period, and also is a main characteristic of contracts that important particulars are not spelled out sufficiently by the partners. It follows that their content has to be improved in the future. -
The significance of ecolabels in tourism
118-124Views:191More than one hundred types of ecolabels have been introduced worldwide since the 1980s. These voluntary certifications may play a prominent role in achieving sustainable tourism as, on the one hand, they may encourage companies to behave responsibly, and on the other, they may contribute to increasing tourists’ awareness in their choice. Considering that there are many small and medium-sized companies working on the tourism market, developing voluntary certification systems is highly encouraged in the member states of the European Union.
At the same time, there are significant differences among the various ecolabels concerning their content, qualitative criteria, and requirements, which makes it difficult for them to gain acceptance on the tourism market. It is worth mentioning that the sets of criteria belonging to the ecolabels usually do not involve indicators related to the social and cultural impacts of tourism.
In my paper I review the main characteristics of voluntary certifications with special emphasis on the players in tourism ecolabels, furthermore I discuss their advantages and some of the arising problems as well. -
Inland and foreign Erwinia amylovora isolates by carbohydrate utilization
29-33Views:165Fire blight, a plant disease caused by the bacterium Erwinia amylovora, produces serious losses in apple and pear orchards all over the world. Since the appearance of fire blight in Hungary (Hevesi, 1996) Erwinia amylovora isolates were collected in different years, from different hosts and areas in order to establish gene bank for future epidemiological studies. We had isolates from foreign countries as well. The aim of our research was to compare all of the Hungarian and foreign isolates by carbohydrate utilization.
In our experiments effect of carbohydrates on E. amylovora multiplication was determined using API 50 CH strip (bioMérieux, France). By the API 50 CH strip method we checked a number of unstudied carbohydrates. The results of the tests shows colour changes. Based on utilization of 49 carbohydrates of API 50 CH kit by E. amylovora isolates, two groups of carbohydrates can be defined: “Utilized” - and “Not utilized” carbohydrates. All isolates utilized 20 different carbohydrates after 164 hour incubation. Conversely, isolates also could be divided into four groups (1, 2, 3, 4) by arbutin and raffinose utilization. In group 1.-isolates utilize arbutin; 2.- utilize raffinose; 3.- utilize both arbutin and raffinose; 4. -utilize neither arbutin nor raffinose. Presumably carbohydrate content of nectar could play an important role on invasion of the (E. amylovora) bacterium via flower.
It could be concluded that the carbohydrate utilization – completed with genetic analysis – can be used for characterization of Erwinia amylovora isolates. -
Genetic Diversity of Hair Colour in Horses
40-45Views:214The main aim of this study was to analyze sources of variability for coat colour expressed as a quantitative trait as well as to determine non genetic factors influencing horse colour variation and shades. Traditional Hungarian horse breeds such as Lipizzan (grey), Gidran (chestnut), Shagya Arabian and Arabian Pure Bred (grey) and Nonius (bay and black) horses were involved in the current study. We report results using direct measurements of horse coat colour using objective colorimetric dimensions and a spectrophotometer for determining hair melanin. Correlation analysis indicated that the single biological component that correlated best with the total melanin content of horse hair is the L* value (r=-0.858, p<0.0001). Subjective colour classes and coat colour variables L* and a* were obviously related, with R2 values of 0.88 and 0.46 respectively, with a lower R2 for b* of 0.22 (all p<0.001).
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Impact of environmental changes resulting from different sowing dates on maize yield
99-104Views:336Three Debrecen maize hybrids of different genotypes (Debreceni 285, Debreceni 377 and Debreceni 382) were examined on chernozem soil in a field experiment. During the two years of the experiment (2009–2010), we wanted to get to know how the examined hybrids reach to different sowing dates and what impact early, optimal and late sowing has on yield.
In 2009, balanced soil and air temperature resulted in steady emergence. However, the low temperature in early April and the cooling down in mid-May 2010 caused a delayed emergence.
The grain moisture content at harvesting and the high yield showed a strong crop year effect. In 2010, yield was much lower (1.664 t ha-1) and grain moisture was significantly higher (34%)than in 2009.
In 2009, early sowing resulted in yield decrease (P<0.05), but it also significantly reduced grain moisture at harvesting (P<0.05). Although late sowing slightly increased yield (not significantly), but grain moisture at harvesting increased by 9.2%. In 2010, optimal sowing date was shown to be the best alternative from the aspect of yield, but there was no significant difference in comparison with early and late sowing. Grain moisture at harvesting greatly increased (13.3%).
The Debreceni 382 maize hybrid reacted to sowing dates flexibly, neither early, nor late sowing affected its yield significantly and the grain moisture at harvesting showed 12% increase in the case of the late sowing date. In 2009, maize hybrids Debreceni 285 and Debreceni 377 reached their highest yield in the case of the sowing date which was shown to be optimal (23rd April), while the different sowing dates had no effect on yield in 2010.
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Integrated nutrient supply and varietal difference influence grain yield and yield related physio-morphological traits of durum wheat (Triticum turgidum L.) varieties under drought condition
111-121Views:354The ever-growing world population entails an improvement in durum wheat grain yield to ensure an adequate food supply, which often gets impaired by several biotic and abiotic factors. Integrated nutrient management, such as nitrogen rate × foliar zinc × sulphur fertilization combined with durum wheat varieties were investigated in order to examine the dynamics of yield and yield related physio-morphological traits under drought conditions. The four durum wheat varieties, three-level of nutrient supply (i.e. control, sulphur, and zinc), and two nitrogen regimes (i.e. zero and 60 kg ha−1) were arranged in split-split plot design with three replications. Zinc and sulphur were applied as foliar fertilisation during the flag leaf stage, both at a rate of 3 and 4 liters ha-1, respectively. Results showed existence of genetic variability for grain yield, plant height, NDVI, SPAD and spike density. Foliar based application of zinc and sulphur at the latter stage improved the plant height. Nitrogen fertilized varieties with lower spike numbers showed to better yield formation. Co-fertilization of nitrogen and zinc improved grain yield of responsive varieties like Duragold by about 21.3%. Spikes per m2 were statistically insignificant for grain yield improvement. It could be inferred that the observed positive effect of sulphur, nitrogen and zinc application on physio-morphology and yield formation substantiates the need to include these essential nutrients in the cultivation system of durum wheat.
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The toxic effects of aflatoxin microorganisms in plants used as spices
59-62Views:225As an extension of the analysis of black, white and capsicum peppers for aflatoxins , we have examined an additional 11 types of spices and
4 herbs for these mycotoxins. The investigations consisted of assessment of the applicability of available methods of analysis and modifications of
these, where necessary together, with a limited survey of each spice and herb for aflatoxins. The analysis of 13 types of ground spices reported
the presence of low concentrations of aflatoxins in some samples of black pepper, celery seed, and nutmeg. We decided to include in our study 5
of the spices examined by these workers (cinnamon, celery seed, coriander, nutmeg, and turmeric) for a comparison purpose. In addition we
examined ginger, mace, cumin seed, dill seed, garlic powder, onion powder, and the herbs marjoram, rosemary, thyme, and sage. -
Usage of different remote sensing data in land use and vegetation monitoring
7-12Views:340The use of remote sensing in forest management and agriculture is becoming more prominent. The rapid development of technology allowed the emergence of database suitable for precision application in addition to the previously used low-resolution and low data content images. The high resolution, hyperspectral images are not only suitable for separating the different land use categories and vegetation types but also for examining the soil characteristics and biophysical features of plants (Blackburn and Steel, 1999; Condit, 1970). We processed a multispectral satellite image (Landsat 7 ETM+) and a hypespectral areal image (DAIS 7915) about a farm on the plains and evaluated the different image classification methods. During our examinations, we examined the geometrical and radiometrical characteristics of images first, then assigning the training areas, we determined the spectral characteristics of land use categories. We performed a multispectral analysis for checking land use, where we compared controlled and uncontrolled classification systems to check their reliability. We used areal and spectral reductions to make the classifications more accurate and to reduce the length of calculations.
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Pre-treatment of wastes containing keratin in industrial conditions
59-64Views:552The aim of the research was a development of a featherdegradation technology in industrial circumstances. During the experiments we determined the parameters of the critical environmental and technological limitation factors. Because of the high keratin-content the degradation (and composting) of the feather is difficult. With the developed technology huge mass of feather can be used fast and easily in biogas production and in the adjustment of the optimal element ratio of biomass. The industrial experiments were implemented in a 6m3 heatable double-walled
tank with stirring-shovels and aeration-system. The degradation process was followed with extinction measurements.
According to the experiments that were done the best results were given at the case which was heat-treated at 70°C, was injected with 1% bacteria concentration, and where 1:3 feather:water ratio was set if we consider the effectiveness of degradation and the hydraulical retention time. -
The influence of fertilization on the soil characteristics of a calcareous chernozem in a long term experiment
47-52Views:288In the long term fertilization experiment of the University of Debrecen, Centre for Agricultural and Applied Economic Science(CAAEC) (Debrecen Látókép), the effects of a 25-year-long fertilization were examined in terms of some chemical and microbiological properties of soil. With the growing doses of fertilizers, the available nutrient content of soil increased. At the same time the pH significantly decreased, while the hidden acidity increased. Moreover, the ratio between the soil bacteria and microscopic fungi, and the occurrence of microbes also changed. The number of sensitive physiological bacteria groups decreased dramatically. These changes indicate the reactions of living organisms; they correspond to the „resistance stage” of stress effects, but in the case of nitrifying bacteria, they reach the „exhaustion stage”.
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Mitigation of environment impact of mycotoxins produced by Fusarium species
159-164Views:500The Fusarium fungi hazards the grain quality of cereals, therefore significantly affects their utilization as animal feed or consumable product. The Fusarium can decrease the quality of wheat in different ways: decreases the germination capability, causes visible discoloration, mould may appear, reduces the dry material and nutrient content of the grain, causes mycotoxin infection – as a result given by its by-product. Micotoxins produced by Fusarium genus, as the trichotecenes (T-2, HT-2, deoxynivalenol, nivalenol, diacetoxyscirpenol, Fusarenone-X) and the zearalenone (F-2) are the most common in Hungary. Occurrence of fumonisins first discovered in 1988 are must be identified carefully. About 20–30% of the overall worldwide production of cereals is infected with Fusarium and its toxins, which situation is similar in Hungary. This infection causes serious yield-losses in cereal production. In the case of cereal products, which non-utilizable as forage seems, an optimal solution is utilizing as biogas raw material, but it is also important to examine the effect of the infected cereal on the anaerobe digestion process.
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Use of essential trace elements enriched Artemia in the larval rearing of barramundi (Lates calcarifer)
11-16Views:401Artemia is a vital nutriment in the rearing of barramundi (Lates carcarifer), however it’s mineral trace element content does not cover the requirements of the larvae. In our experiment the assumption was wether the cobalt, zinc and manganese concentration of Artemia could be increased during a 24 hours of enrichment period, as well as we wanted to investigate the resulted interactions between the elements. For this purpose 50, 100 and 1000 mg l-1 cobalt-chloride treatements (Co50, Co100, Co1000) were applied while in the case of 50 and 100 mg l-1 treatments the enrichment was also complemented with zink-sulphate and manganese-chloride in the same concentrations. According to the results the zooplankton were able to accumulate cobalt in higher amount, and yet zinc and manganese had no significant effect on each other, a strong synergistic effect occurred between cobalt and manganese. After the enrichment period the impact of essential trace element supplemented live feed on the survival and growth of barramundi larvae was also studied. The experiment was carried out by using 15 days-old larvae applying a total of 9 treatments for two weeks (Control, Co50, Co100, Mn50, Mn100, CoZn50, CoZn100, CoMn50, CoMn100), in duplicates. Considering the per cent of survivals, no significant difference was observed between the treatements (P>0.05). In the case of CoMn50 and CoMn100, the loss statistically increased (P<0.05) compared to the Control (80.5±4.95%) group. Our results show, that the Mn100 and CoMn100 treatements resulted in ignificantly higher (P<0.05 ) in divid ual bod y w eight s, how ever taki ng the survival also into consideration the Mn100 treatements proved to be the most
effective.