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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. -
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:193More 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:215The 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:226As 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:341The 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. -
Amelioration and arable land-use possibilities of Solonetz soils in the Trans-Tisza region of Hungary
107-117Views:309Salt 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.
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Technological development of sustainable maize production
83-88Views:309In our research we examined the effect of the hybrid, the nutrient supply, the number of plants and the abiotic factors (temperature, amount of precipitation) on the yield, crop quality and yield stability of maize. We devoted special attention to the natural nutrient utilization ability and fertilizer reaction of maize.
The experiment took place in Hajdúszoboszló on chernozem soil, on a nearly eight ha field. The size of one plot was 206 m2, this it was a half-industrial experiment. We tested six hybrids with different genetic characteristics and growing seasons. I analysed the correlation between the nutrient supply and the yield of maize hybrids with control treatment (treatment without fertilization) and with N 80, P2O5 60, K2O 70 kg ha-1 and N 160, P2O5 120, K2O 140 kg ha-1 fertilizer treatments. Yield increasing effect of the fertilizer also depended on the number of plants per hectare at a great extent. The number of plants of the six tested hybrids was 60, 70, and 80 thousand plants per ha.
In Hajdúszoboszló, in 2016 the amount of rainfall from January to October was 605 mm, which was more than the average of 30 years by 160 mm. The yield of hybrids without fertilization changed between 9.63–11.6 t ha-1 depending on the number of plants.
The six tested hybrids is 10.65 t ha-1 in the average of the stand density of 60, 70 and 80 thousand plants per hectare without fertilization, while it is 12.24 t ha-1 with N80+PK fertilizer treatment. That increase in the yield is 1.6 t ha-1, it is significant.
Da Sonka hybrid is sensitive to weather, it is able to produce 6 t ha-1 additional yield in case of favourable condition. However, it has a low stress tolerance. The most stable yields were observed at Kamaria and Pioneer hybrids. The effect of vintage is also an important factor on the yield. In average, the yield of maize was 6.81 t ha-1 in 2015, which was a drought year and 11.86 t ha-1 in 2016 that was a favourable year. -
The effect of washing for the shelf-life parameters of spinach (Spinacia oleracea L.)
131-135Views:545Spinach is a very popular green leafy vegetable because of its versatile usage and beneficial for the health. However, spinach may contain several pathogen bacteria: Escherichia coli, Klebsiella spp., Salmonella spp., Enterobacter spp., Citrobacter spp., Shigella spp. and Listeria monocytogenes, which can cause several serious health problems. This study investigates the effects of washing with citric acid for the shelf-life parameters of spinach in comparison to the effect of washing with water and control. Washing of spinach with 0.5% citric acid solution decreased the elasticity of the spinach leaves, as well as the chlorophyll content. On the other hand, the total plate count, as well as the yeast and mold count could be decreased with this treatment, but difference was not detectable at the forth storage day. The fecal indicator E. coli did not change, indicating washing was not effective in this case. Further optimisation of treatment and storage conditions may decrease microbial risk of fresh spinach consumption without decreasing its sensory quality.
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Effect of compost/water ratio on some main parameter of compost solutions
117-121Views:827Composting is an efficient technology for the utilisation of by-products and waste. It is also suitable for treating raw materials to convert fertilisers that are not recommended for application without pre-processing. Such is the case with poultry manure, which is very important to pre-treat due to its hazardous properties. An increasingly common form of compost is compost tea, which is made by soaking compost in water. In our experiment, we made compost tea from a composted and granulated poultry manure product. Three mixing ratios were used (1/5, 1/10, 1/10) and compost teas were set for three different extraction times (24–48–72 hours). After elimination of the experiment, the pH, EC, and nitrate and ammonium contents of the samples were measured. The aim of this study was to determine whether there is a difference between each mixing ratio and different extraction times. Based on our results, it can be said that the fluctuation of pH values during the experiment was low. Regardless of the mixing ratio and extraction time, the samples were in the slightly acidic range. The electrical conductivity, nitrate and ammonium content follow a similar trend, the values decrease significantly with the increase of the mixing ratio. Similar tendency was observed at the incubation time. The concentrations of both EC and nitrogen forms increase with increasing incubation time, in most cases significantly.
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The effect of herbs on the microbiological stability and nutritional quality of pariser
101-104Views:233The purpose of this study was to evaluate the functional properties of dried herbs (Thymus vulgaris L., Origanum vulgare L., Salvia officinalis L.) to improve the quality characteristics and microbiological stability of Hungarian meat product, pariser. The addition of herbs did not affect the microbial properties of the product. According to the Decree No. 4 of 1998 of the Ministry of Health, pariser can be considered safe. The nutritional quality of the different forms of pariser was also acceptable. However, the addition of oregano, sage and thyme changed the flavor characteristics of the parisers and the higher meat content would increase the final price of the product.
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Effects of diets with different fibre content on the performance of rabbit does and on parasitological infection
41-44Views:299The effect of two diets with different fibre contents was examined on rabbit does’ performance and parasitological infection. Diet P2 had 1% higher crude fibre, ADF and starch contents than that of diet P1. The performance of 12–12 does and litters per group were examined during two consecutive inseminations. In both dietary groups, according to a 49-day reproduction rhythm, the does were artificially inseminated 18 days after kindling. Most production traits were not affected by the diets (kindling rate, weight of does and their kits, feed intake, mortality; P>0.05). Significant differences were only found in litter sizes as the number of kits was lower in P1 diet fed group at all examined days of lactation. The significant “Diet x Reproduction cycle” interaction showed that the litter sizes of dietary groups did not differ at the first examined insemination, however at the subsequent reproduction cycle 6–8% lower litter sizes were counted in P1 fed does compared to group P2 (litter size at 4 day: 9.00 vs 9.58–9.92, P = 0.004; litter size at 11 day: 8.83 vs 9.58–9.92, P = 0.037 for diet P1 at the 2nd reproductive cycle compared to all the other cases, respectively). The two diets with different compositions did not affect most of the production results of the rabbit does and their kits, but the lower litter size of does consuming P1 diet at the second examined lactation suggests the adverse effect of P1 diet’s long-term use. From the collected manure samples not any parasites were detected which presents a very favourable picture of farm from the point of view of hygiene and animal health.
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Influence of Foliar Treatments on the yield and quality of Sugar Beet
119-123Views:471The yield and quality of the sugar beet are mainly determined by the plant production system, thus we studied the effect of mineral fertilization. Our field trials were carried out in 2005 in Hajdúböszörmény, at two sites. We studied the effect of sulphur (Cosavet DF), copper (Kelcare Cu) and two foliar nutrients with high active agents. Treatments were replicated four times.
We took root samples at 4 week intervals, starting in August. The quality of root (sucrose, potassium, sodium and alfa-amino N content) was determined from filtrated beet broth, by an automatic beet laboratory system, called VENEMA.
We found that the crop and the sugar yield were significantly influenced by the foliar treatments -
Effect of fish feeds with high vegetable oil and low fish oil content on the growth performance and innate immune system of common carp (preliminary results)
7-12Views:203Fish meal and fish oil are very important components of fish feeds used by aquaculture. They contain poly-unsaturated fatty acids, which are essential nutrients both for fish and human nutrition. However, sources of fish meal and fish oil are limited, there is a need for new feed components to supply the increasing fish production and the increasing demand for fish feed. The aim of AQUAMAX project, supported by the European Union is to replace the fish meal and fish oil with vegetable oils. As a participant of this project, group of immunology in Research
Institute for Fisheries, Aquaculture and Irrigation (HAKI) examined the effect of three different fish feeds on the growth performance, innate immune response and resistance against Aeromonas hydrophila infection of common carp in an in vivo experiment. Fish feed supplemented with Camelina oil, but still containing fish oil significantly increased growth performance of experimental fish and their resistance against the infection. Fish feed containing linseed oil only did not enhance the growth performance, and it had a negative effect on resistance against infection. Based on the experimental results it can be concluded that fish oil used in fish feeds cannot be replaced effectively with vegetable oils, but can be supplemented with them. -
Biomethane production monitoring and data analysis based on the practical operation experiences of an innovative power-to-gas benchscale prototype
399-410Views:634Power-to-gas (P2G) is referred to technologies that convert carbon dioxide into methane. Both bio- and chemical catalysts may be used for conversion purposes. One of the most disruptive biotechnologies was developed by the University of Chicago (IL) (publication number: EP2661511B1), using a robust, highly selective, patented strain of Archaea. Electrochaea GmbH has developed an innovative bench-scale P2G prototype unit, which uses this highly efficient Archaea strain, specialized components and specifically developed control strategies. The structure and the components of the prototype are equivalent with the functional parts of the currently largest commercial scale biomethanation BioCat plant located in Avedøre, Denmark (www.biocat-project.com). Power-to-Gas Hungary Kft. has committed to further develop this innovative technology. The first steps of this development have been taken by operating the benchscale unit and analyzing the data of the operating periods.
The prototype is operated based on weekly campaigns. During continuous operation, H2O is generated as a by-product of methane. Therefore, approximately 200 ml of biocatalyst is discharged each day and concentrated media containing macro and micronutrients are injected into the reactor to maintain media composition. The laboratory staff records all gas composition data each morning. The gas composition is measured every 12 minutes by an Awite AwiFlex Cool+ gas analyzer. Within this article, we analyze the collected datasets containing more than 12 000 records and present the first practical experiences of the operations of the innovative power-to-gas bench-scale prototype.
The analysis of the collected gas composition data of the product gas already provides important data for modelling the commercial-scaled processes. The average value of VVD was about 40 l/l/d in the period under review. Further increase of the methane content can be achieved by introduction of higher mixing energy and by increasing pressure levels in the bioreactor (as demonstrated in the BioCat plant – data not shown here) – both of which are strategies envisioned for the commercial plant. In routine activities (turn on, shut down, continuous operation) we could verify the high robustness of the biocatalyst and the base connection between the registered datasets and performed test results.
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Preliminary test: Evaluation and selection of tomato (Lycopersicon esculentum Mill.) varieties resistant to drought and powdery mildew
33-37Views:331Powdery mildew (Leveillula taurica) and (Oidium neolycopersici) are two harmful fungi that invade the tomato (Lycopersicon esculentum Mill.) plant and grow in dry conditions. Under the influence of polyethylene glycol 6000 at a concentration of 12%, the total seedlings fresh weight, total seedlings dry weight, seedling growth rate of one seedling, seedling length, and tissue water content percentage for three tomato varieties were assessed. Despite the superiority of the (Mobil) tomato variety in terms of numerical values, the results revealed no significant differences between varieties. As a result, (Mobil) has greater vigor under environmental drought stress of lower osmotic stress than other tomato varieties. More work is required to evaluate the research selection of varieties resistant to biotic stresses in dry areas, such as powdery mildew disease.
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Effect of tillage practices, fertilizer treatments and crop rotation on yield of maize (Zea mays L.) hybrids
43-48Views:501This research was conducted at the University of Debrecen Látókép Research Station and is part of an ongoing long-term polyfactorial experiment. The impact of three tillage systems (Mouldboard plowing-MT, Strip tillage-ST, Ripper tillage-RT) and two levels of fertilizer treatments (N80 kg ha-1, N160 kg ha-1) along with a control (N0 kg ha-1) on the yield of maize hybrids (Armagnac- FAO 490 & Loupiac-FAO 380) cultivated in rotation with winter wheat was evaluated during a two-year period (2017–2018).
Amongst the three tillage treatments evaluated, ripper tillage (RT) had the highest average yield (10.14 t ha-1) followed by mouldboard tillage (MT) and strip tillage (ST) with 9.84 and 9.21 t ha-1 respectively. Yield difference between RT and MT was not significant (P>0.05), as compared to ST (P<0.05). Soil moisture content varied significantly with tillage practices and was highest in ST, followed by RT and MT (ST>RT>MT). Yield of RT was 7–9% higher than MT in monoculture plots, while MT reign superior in biculture plots (monoculture: RT>MT>ST; biculture: MT>RT>ST).
A positive interaction between tillage and fertilization was observed, with higher yield variation (CV=40.70) in the non-fertilized (N0) plots, compared to those which received the N80 (CV=19.50) and N160 kg ha-1 (CV=11.59) treatments.
Incremental yield gain from increase fertilizer dosages was significantly higher in monoculture, compared to biculture. There was no significant difference in yield between N160 and N80 in the biculture plots (12.29 vs 12.02 t ha-1). However, in monoculture plots, N160 yield was 23% higher than the N80 kg ha-1 (N160=11.74 vs N80=9.56 t ha-1).
Mean yield of maize in rotation with winter wheat was 28% (2.47 tons) higher than monoculture maize. The greatest benefit of crop rotation was observed in the control plots (N0) with an incremental yield gain of 4.39 tons ha-1 over monculture maize (9.92 vs 5.43 t ha-1).
Yield increased with higher fertilizer dosages in irrigated plots. Fertilizer application greatly increased the yield of maize and accounted for 48.9% of yield variances. The highest yield (11.92 t ha-1) was obtained with N160 kg ha-1 treatment, followed by N80 kg ha-1 (10.38 t ha-1) and N0 kg ha-1 (6.89 t ha-1) respectively.
Overall mean yield difference between the two hybrids was not statistically significant, however, yield of FAO 380 was 3.9% higher (9.06 vs. 8.72 t ha-1) than FAO 490 in monoculture plots, while in biculture plots, FAO 490 was 4.1% higher than FAO 380.
Average yield in 2018 was 13.6% (1.24 t ha-1) higher than 2017 for the same set of agrotechnical inputs, thus, highlighting the significant effect of cropyear.
Armagnac (FAO 490) cultivated in rotation with winter wheat, under ripper tillage and N80 kg ha-1 is the best combination of treatments for optimum yield.