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Calculating possibility of the leaf area index of apple and pear trees
229-233Views:128A significant proportion of the aboveground green and dry weight of the plant constitutes the foliage. The canopy is an important factor of plant growth. On one hand the canopy absorbs the solar energy, which is necessary for the photosynthesis, on the other hand accumulates the absorbed nutrients by the roots, and the most of the water-loss happens through the foliages. The determination of the full canopy is not an easy target. In our research we developed a measurement method to determine the leaf area. With the parameters of the examined tree (leaf length and maximum width) and the data of ADC AM 100 leaf area scanner we determined the k-value, with which we can easily and fast evaluate the leaf surface.
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Research on rheological characteristics of winter wheat varieties
266-272Views:140The gluten examination test is dominant in Hungary, comparing it to the qualification system of other countries. The determination of alveographic parameters is a basic criterion of winter wheat specifications in some western and southern European countries.
In the Hungarian and foreign winter wheat qualification systems, in the standards, there is no limit for extensographical parameters. Customers dictate the limits and make their claims as to the specifications.
We analyzed the alveographic and extensographical parameters of 19 winter wheat varieties grown by the Cereal Research Non-Profit Company in Hungary, and we made a comparison between the results in the challenges of the European Union expectations.
Examining the information of alveographic and extensographical values, we found that the experimental varieties provide high base to flour types suitable for baking bread and baker’s ware. The GK Élet, GK Petur, GK Memento, GK Csillag, GK Kapos and GK Marcel varieties can meet the market of paste flour needs, too.
In the variety series, the GK Kalász represents the highest values and the GK Garaboly shows the lowest parameters regarding the alveographic W and the resistance to extension.
On the basis of relation, we can establish that we can estimate the following little known and used quality indexes: the extensographical resistance to extension with extensographical energy and the alveographic W value, the extensographical energy with the alveographic W value and the alveographic P and L values with the other alveographic parameters. -
Spectral analysis of stress symptoms caused by apple powdery mildew (Podosphaera leucotricha
83-88Views:187An orchard can be examined on the basis of spectral data, using methods with which the reflected radiation can be divided into a large number of (several hundreds) small spectral channel (some nm). Calculated on the basis of such hyperspectral data from different index numbers the water supply of foliage conditions can be well characterized.
The research site is an intensive apple orchard, which located in University of Debrecen, Agricultural Sciences Centre, Farm and Regional Research Institute at Pallag. During my experiments the preliminary evaluation of spectral, non-invasive measurement method are carried out for detecting stress symptoms caused by Podosphaera leucotricha.
Based on the results narrow band greenness indices (NDVI705, mNDVI705, mSR705 and REP) can be used for determination of diseased canopy and for the detection of stress symptoms of Podosphaera leucotricha,. These statements can be utilized in precision plant protection systems, since it can be a basis for such integrated active sensors with LED or laser light source, measuring reflectance at the certain spectral range, which can facilitate real time status assessment of orchards and can control precision fungicide utilization.
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Comparative analysis of maize weed control system and the competitive effect of sorghum
97-104Views:91In our investigation we used different weed control technologies in the different phenology states of the maize. The experiment have been
carried out in Hódmezővásárhely, in the Experiment garden of the Pilot farm of University of Szeged Faculty of Agriculture, on meadow
chernozem soil, on 24 m2 plots, in 3 replications, randomized blotch design. The experiment can be regarded as 15 weed-control strategies
where, in addition to the untreated control, six chemicals or chemical-combinations are applied (Spectrum 720 EC, Motivell Turbo D,
Stellar + Dash HC, Clio + Akris SE + Dash HC, Clio + Dash HC) in five different times (pre, early post, post and two late post) and eight
mechanical weed-control technologies were used. Hoeing took place connected to the herbicide treatments in different times: until 2-3-leave
age weedless, in 3-4-leave age hoed once, from 3-4-leave age weedless, in 6-7-leave age hoed once, from 6-7-leave age weedless, in 8-leave
age hoed once, from 8-leave age weedless.
Our results were assessed by chemical efficiency examination, maize length measurement, corncob-length and fertility examination,
Sorghum plant-number determination and yield weighing carried out in four periods. The data were evaluated by a one-factor analysis of
variance and a two-factor linear regression analysis. -
Biotechnological methods for improving reproduction on sheep breeding program using laparoscopic artificial inseminations in Debrecen, Hungary
193-200Views:75The aim of this study was to evaluate the results of the LAI method in different types of breeds and seasonal variations. Analysing n=536 LAI in 7 years, there were no significant differences observed in the breed in lambing rates. Although the lambing rate of Prolific Merino (F+) was better than any other breed (45.3%). We found significant differences between breeds of Tzigaia, its pregnancy rate was 19.2%. In the case of prolificacy there were significant differences between breeds: Prolific Merino’s (FF) was the highest (2.38) and, Indigenous Tzigaia’s was the lowest (1.4) from all of them. The obtained results showed that summer inseminations were the most effective in concern of pregnancy rate (49.5%). The results are based on use of the types of semen, showed that using frozen semen was most effective than fresh semen in both parameters, however there were no significant differences. Summarising all tested conditions in our study breeds, seasons and type of semen using LAI the total results of pregnancy rate was 40.3% and the prolificacy was 1.78, respectively. Follow up the out-of-season ovarian, progesterone level of n=36 Prolific Merino were examined and insulin, IGF-1, leptin, T3, and T4 hormones as well, to evaluate the energetic status of the flock. Progesterone analysis showed 43% of examined ewes had a cyclical ovarian function in April and a cyclical ones had good reaction for estrus-induction hormonal treatment. Our results showed that valuable information can be obtained about energy supply from the determination of some metabolic hormones as IGF-1, insulin, leptin.
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Connections of the Economic, Ecological-Environmental and Social Functions of Rural Development in Communities Bordering the Hortobágy
203-211Views:77investigated the economic, ecological-environmental and social functions of rural development in communities bordering the Hortobágy National Park, such as in Balmazújváros, Hortobágy, Tiszacsege and Egyek. My purposes focused on four issues: (1) to work out a method on the basis of the examined and cited literatures, which defines the development of communities from economic, ecological and social aspects of rural development; (2) to reflect the changes in the role of agriculture; (3) to analyse the effects, advantages and disadvantages of Hortobágy National Park in relation to the economic, ecological and social lives of the examined communities; and (4) to make an economic analysis on the alternative income sources of Hortobágy, such as rural tourism, herb production and bio-farming in a family farm structure. When measuring the development of the communities I concluded that complex indexes hide the real consideration of the three functions of rural development and the possibility for comparing them on a community level. Furthermore, these 19 indicators are not enough to evaluate the situation, thus I raised the number of indicators and handled them on the basis of the three functions of rural areas. I classified the economic, ecological and social indicators into indicator groups within each functions, which make the determination of causes for underdevelopment possible. While only Tiszacsege and Egyek were considered to be backward on the basis of the complex index of the Hungarian Central Statistical Office, my investigations showed that even Balmazújváros and Hortobágy proved to be lagged behind from both economic and social aspects. The methodical development justified the hypothesis that few indicators are not enough to establish decisions objectively. New developmental orders emerged. Measuring development of communities may be all-rounded and more established by using this new method, which may result in objective preparation of decisions in rural development and more rational spreading of subsidies.
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Comparison of sample preparation methods for the identification of Staphylococcus Aureus by MALDI-FOF MS
9-14Views:281Coagulase-positive staphylococci include 3 species, Staphylococcus aureus, S. hyicus and S. intermedius. Of these three species, S. aureus is the most well-known human pathogen. S. aureus is part of the human and animal normal microbiota, however, it is capable of producing several staphylococcal enterotoxins (SEs) that cause intoxication symptoms of varying intensity in humans after consuming contaminated food. Selective media which are used for the determination of coagulase-positive staphylococci from foods are not able to identify isolates at a species. With the MALDI-TOF MS technique, we can identify S. aureus cheaper and faster than by using molecular methods. This paper describes the results of the study of the presence of coagulase-positive staphylococci and S. aureus in many food products, and the application of three sample preparation methods: direct sample preparation, formic acid suspension and ethanol extraction.
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New methods of compost homogeneity determination in sewage sludge based compost prisms
49-52Views:157There is no effective method of homogeneity measurement of compost prism. The most frequently used technology is the examination of the particle distribution. This method needs a lot of time and large number of samples. The aim of our research is establishing different effective methods to determine the homogeneity of compost prisms. During our work, we examined the homogeneity of a prism made of sewage sludge and saw-dust mixture.
The measurements were based on the different properties of raw materials. According to this we examined the homogeneity by moisture content, heavy metal content and gas distribution measurements.
The most effective method is the measurement of gasconcentration. Although gas-concentration measurements it need special equipment it has more advantages than the other methods. The examination of gas-distribution compensates the problem of sampling because the measurement is direct. It provides the opportunity to estimate the amount of emitted toxic gases and to determine the maturity of the compost and the effectiveness of the degradation. -
Water infiltration into the soil – what do measurements indicate?
343-351Views:144Physical properties of top-soil organic materials significantly influence initiation processes of infiltration and runoff generation. This paper deals with the specifics of water infiltration through the top surface organic layer of the forest soil. Three field methods (Guelph permeameter, Tension disk permeameter, Single-ring method) and one laboratory method (Falling head) of hydraulic conductivity (KS) determination are compared and interpreted in the context of their applicability and limitations. The Falling head method provides far different values of KS if sample cylinders are or are not sealed with grease against the wall effect. The Guelf permeameter is very significant to the position of different horizons’ interface, while Tension disc permeameter results are dependent on antecedent soil moisture. The single ring method is applicable with acceptable results only when there is no abrupt interface between horizons in the vicinity of the ring bottom edge.
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Using sensors in precision crop production
267-270Views:127Proper plant nutrition that takes into consideration both the requirements of plants and ecological conditions is one of the most important precondition of successful plant production. An important element of the N-fertilization of wheat is that the optimum zone of nitrogen supply is significantly narrower than that of other plant species, therefore it can easily happen that we apply higher or lower nitrogen doses than the optimal one. A possible solution to this problem can be precision agriculture. Applying the methods of precision agriculture we can take into consideration the heterogeneity of fields. By applying precision methods either online or offline we can intervene faster than if we would rely only on regular soil and plant analysis procedures. The determination of the doses of nitrogen and the timing of application are influenced also environmental and
economic aspects. The chlorophyll content of the leaves indicates the nitrogen status of plants, since there is a relationship between the nitrogen content and the amount of chlorophyll in the leaves. According to plant analysis results there was a strong and significant relationship between the values of the NDVI (Normalized Difference Vegetation Index)and the total nitrogen content measured in the leaves. -
Analyzing the Population Retaining Ability and the Ability to Economically Provide for a Population in the Micro Region of Püspökladány
210-219Views:72According to the data of population density, 98% of Hungary’s territory has rural features. Gaining EU supports, in order to focus on developing the most underdeveloped communities, and in order to decrease – not to increase – the differences between communities, the establishment of priorities and determination of the rank of rural communities based on their development potential is necessary. The claim of measurability arises because of comparison and classification. A possibility or a target area of measuring is analysing population retaining and income producing capability of rural areas.
To gain adequate, many-sided information about the development potentials of a given community, micro- or macro region, complex condition survey, as well as secondary information completed with empirical data and subjective value judgment is essential. The aim in every case is to gain experience of the present condition via determining the direction of change.
In this study, I deal with the clarification of the definition of population retaining ability and the ability to economically provide for a population and introduce the most important results of the inquiry with questionnaires completed in the frame of an empirical survey. -
Study of the biodegradation of slaughterhause feather waste by Bradford method
77-81Views:131The 15–20% of the by-products of meat- and poultry industry – that unsuitable for human consumption – contains keratin. The slaughter technology of poultry produces large amount of poultry feather with 50–70% moisture content. This means more million tons annually worldwide (Williams et al., 1991; Hegedűs et al., 1998). The keratin content of feather can be difficulty digested, so physical, chemical and/or biological pre-treatment is needed in practice, which has to be set according to the utilization method. The microbiological and enzymatic degradation of feather to soluble protein and amino acids is a very favourable and relatively cheap opportunity to produce valuable products of the resulting feather. Our applied treatments were based on the determination of the most effective method, which is able to follow the biodegradation of waste poultry feather.
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Growth and yield patterns of black locust (Robinia pseudoacacia L.) sample trees affected by site conditions: case studies
125-128Views:51The trees removed from the long-term experiment plots are available for the measurements as lying trees. Through the determination of the volume in sections along the stem, the stem form, the stem volume and other factors can be specified. The comparison of the stems of individual trees of first and third yield classes of black locust (Robinia pseudoacacia L.) stands shows that site conditions have a main effect on the yield (mean tree volume). The difference can be as high as 53% at the age of 30 depending on the sites. To determine the growth patterns based on tree volume is rather a new approach in the light of the relevant literature. The obtained results also highlight the importance of choosing the appropriate tree species for a given site.
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The Valuation System of the National Land Fund
317-323Views:82The aim of establishing a National Land Fund was to realise the rational management of land property belonging to the Hungarian State, to assist in the realisation of estate political directives, and also to support the development of a modern property structure based on family farms. During this 3 years operation the National Land Fund has become the major player of the Hungarian land market. It has arranged land trades totaling 15,000 hectares, which makes 50% of total related turnover. The NLF created the reason for the existence of land as credit security with the provision of security of mortgage credits. National Land Fund has written co-operation contracts with 11 commercial banks in order to provide long-term agricultural mortgage with the background of land security. NLF has issued almost 1,000 conditional declarations of land purchase to the banks, helping the credit system of agricultural companies.
The valuation system „TÉR” created by the National Land Fund, is a many-sided, flexible system adjusted to Hungarian conditions. This evaluation system can determine the value of land in a reliable way. NLF built further controls into the process with the co-operation of independent revisers providing real determination of land value. -
Characterisation of a thermotolerant yeast, Kluyveromyces marxianus CBS712
7-13Views:118Fermentation at high temperature with application of thermotolerant microorganisms is a technological advantage in bioethanol production. Among the yeasts, K. marxianus has outstanding thermotolarance. The industrial application of the IMB3 strain occurs usually at 45C. The final aim of our project is the genetic modification of the K. marxianus CBS712 strain in order to achieve ethanol production at higher temperature than the currently applied. This requires the characterization of the CBS712 strain, with special attention to the determination of the temperature limit of its growth and the amount of the ethanol produced. The temperature limit of growth was 48C in YPD medium. Elevation of the temperature above 45C led to an exponential drop of the cell viability. Ethanol production was tested in shaking flasks, in MYFM medium, under oxigene limited conditions, applying variable concentrations of glucose (12–20%) and different temperatures (45–47 ºC). Preliminary results have revealed that the elevation of glucose concentration increased the amount of ethanol produced. The amount of ethanol (appr. 5%)+ produced at the highest glucose concentration was not different at the tested temperatures (45, 46 and 47 ºC). The observation indicates the potential in raising the thermotolerance of the strain.
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Investigations of Thrips tabaci and Aeolothrips intermedius population dynamics in tobacco plantations
121-127Views:191Studies were conducted between 2015 and 2017 with yellow sticky traps in seven tobacco plantations. The purpose was to determine when and in what numbers onion thrips individuals can settle into tobacco plantations. The primary objective of the study was to determine the proper timing of chemical treatments, furthermore, the determination of crucial factors that can influence the population dynamics of Thrips tabaci.
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Evaluating of soil sulphur forms changes in long-term field experiments of Látókép
71-76Views:161The aim of this work was to evaluate the changes of different sulphur forms (soluble, adsorbed) in chernozem soil in a long-term field experiment supplied with increasing doses of NPK fertilizers for a long time. In addition, other objective of this study included the examination of the applicability of recommended extractants of the different sulphate fraction in Hungarian soils. A long-term field experiment was established at the Research Station of Látókép of the University of Debrecen in 1984. In addition to control, two levels of NPK fertilizer doses have been used with irrigated and non-irrigated variants. Winter wheat and corn were cropped in a crop rotation on plots. Soil samples were collected in three different development stages of winter wheat, at the stage of stem elongation (April), flowering (May) and ripening (June of 2018) from the topsoil (0–20 cm) of experiment plots. Water-soluble inorganic sulphate was extracted with 0.01M CaCl2 solutions. The soluble plus adsorbed sulphate was extracted with 0.016M KH2PO4 solution. Sulphate was measured by turbidimetric method. 0.01M CaCl2-SO42— ranged between 0.293–1.896 mg kg-1 and the 0.016 M KH2PO4-SO42- varied between 5.087–10.261 mg kg-1. The values of KH2PO4 SO42- was higher than that of CaCl2-SO42-, because KH2PO4 extracted the adsorbed and soluble fractions of sulphate, while CaCl2 extracted the soluble sulphate fraction. The amount of absorbed sulphate was calculated by the differences of KH2PO4- SO4 and CaCl2-SO4. The KH2PO4 characterizes mainly the adsorbed sulphate fraction much more than the water-soluble fraction. KCl is the most widely used extractant for the determination of plant available sulphate content of soil in Hungary; therefore, KCl-SO42- fraction also was determined. The KCl-SO42- ranged between 0.328–2.152 mg kg-1. The CaCl2-SO42- and KCl-SO42- fractions were compared and based on Pearson's linear correlation, moderate correlation was established (r=0.511) between them. In all three extractant (0.01M CaCl2, 1M KCl, 0.016 M KH2PO4) higher sulphate fractions were measured in the fertilized plots where superphosphate had been supplied for ages until 2010. The arylsulphatase activity of soil also was determined and ranged between 9.284 and 26.860 µg p-nitrophenol g-1 h-1. The lowest value was observed in the treatment with highest NPK2 dose, both in irrigated and non-irrigated areas.
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The impact of environmental factors on the measurement of the normalized difference vegetation index
141-147Views:136The level of nitrogen supply of a plant population can be quickly measured with non-destructive optical measurement devices and the differentiated determination of nitrogen shortage and the replenishment of nitrogen can also be carried out. The level of nitrogen supply is based on the fact that the chlorophyll content of crops is in close correlation with nitrogen content and that the amount of chlorophyll can be easily measured on the basis of the light absorption of chlorophyll molecules. The successfulness of optical measurements can be influenced by the change of weather parameters; therefore, it is important to know the correlations between measurement results and weather parameters when it comes to practical use.
The GreenSeeker Model 505 measurement device determines the relative chlorophyll content in the form of the Normalized Difference
Vegetation Index (NDVI) calculated on the basis of the intensity of the reflected red and infrared rays of light from the crop population. The measurements were performed in alfalfa population with 10 replications at five measurement heights and four measurement times. The weather parameters were measured by a weather station located in the middle of the alfalfa population and the correlations between the meteorological data and the NDVI values were examined. During the statistical evaluation of the results, it was established that the NDVI measurement is primarily influenced by the relative humidity of the air, secondly by air temperature and thirdly by wind speed. Relative humidity was in strong correlation with the NDVI values which were also influenced by the measurement height and time. Regression was not significant in the case of 20 cm measurement height, but the measurements above 40 cm height showed significant correlations. The correlation was shown to be strong at each measurement time, but the influence of humidity was the lowest at 11:00 and 14:00. -
Identification of environmental costs for agricultural companies – methodological questions and problems
177-183Views:81It is the consensus in the economic literature that corporate leaders do not know accurately the magnitude of environmental costs in their firms, and this lack of information is often a barrier to making environmentally-friendly decisions. For this reason, an important task of environmental accounting is identification of these costs, and a more realistic distribution of them among the products.
In this paper, we carried out identification of costs and expenditures for Hungarian agricultural companies.
We have dealt with this theme previously, but without detailing the related methodological questions. Detailed discussion is necessary because of the novelty of the subject (environmental accounting for agricultural firms).
Therefore, we elaborate the following questions: scope of determination of environmental costs and expenditures; methods for quantifying specific items; technique for their accounting. We also attempt to confront different viewpoints in the literature. Differences in accounting found between companies investigated are also presented.
The importance of our investigation is related to the significant increase in the number of environmental statutes that concern agricultural companies (e.g. rules for waste treatment, environmental taxation, introduction of charges and fees, regulation on liquid manure). Following these regulations puts an increasingly significant burden on the companies; therefore, the quantifications of environmental cost items has a growing
importance. -
White rust species (Chromista, Peronosporomycetes, Albuginales, Albuginaceae) on common weeds in Hungary
30-33Views:218The obligate plant parasite fungi in the family Albuginaceae are responsible for causing white rust diseases on weeds and they are rather common worldwide. Weedy plants with characteristic symptoms have been collected in 2014 and 2015 on location Hajdú-Bihar and Jász-Nagykun-Szolnok counties in Hungary. The determination of the species were based on the morphological characters both pathogens and hosts. Albugo candida was determined on shepherd’s purse (Capsella bursa-pastoris). Common purslane (Portulaca oleracea) is a host for Wilsoniana portulacae. The fungus Wilsonia bliti (syn.: Albugo bliti), the causal agent of white rust disease was found on redroot pigweed (Amaranthus retroflexus).
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New possibilities to determine wheat quality parameters by near-infrared spectroscopy
65-69Views:155Analyses and methods in wheat quality determination require more sample, time, work and cost, thatswhy flour quality control needs rapid, reliable tools. Near-infrared spectroscopy has many advantages, which make it suitable in quality control. NIR instruments need calibrations to their work. In our study we examined gluten content, falling number, valorigrpahic waterabsorption, alveographic P/L and W value of wheat samples. Modified partial least squares analyses on NIR spectra were developed for each property. The results show that we got such calibration modells, which are able to predict the properties (expect falling number) with enough accuracy.
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Possibilities of mass valuation in land use in Hungary
59-68Views:162Technological development makes it possible to simplify and accelerate decision-making processes by adequately processing and evaluating large volumes of data. Sub-data obtained from large data sets have a very important practical role in asset valuation, forecasting and valuing delineated or difficult-to-map areas, or in the context of portfolio management. Land valuation is a separate segment within asset valuation and it requires a specific methodological approach on behalf of evaluators. In this study, the authors compared the transaction data of arable land and the value of other land use categories. Based on empirical assessments, the authors developed proposals for the fast and cost-effective determination of the value of land use categories other than arable land - mainly meadows and pastures.
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Effects of Cropping Year and Artificial Fertilization on Alveographic Quality of GK Öthalom Winter Wheat Variety
126-133Views:98Qualification of winter wheat became more complex for Hungary, after the expansion of the EU. Use of Chopin alveograph is a general method in Western- and Southern Europe. This method is not traditional in Hungary, so determination of alveographic properties of Hungarian winter wheat varieties is very important. Artificial fertilization is one very important component of applied agricultural engineering, which effects winter wheat quality. The another factor is the weather or rather the cropping year, which effects winter wheat quality too. We examined both of them and the alveographic quality of GK Öthalom winter wheat variety between 1996 and 2003.
We found that cropping year has significant effect on the alveographic quality of GK Öthalom winter wheat variety on each treatment of artificial fertilization. We found no connection between quantities of precipitations of vegetation periods and the W values of GK Öthalom.
We found a strong connection in 1999 and 2003 as well as a very strong connection in 1996, 1997 and 2002, between the increase of fertilizer dose and W values of GK Öthalom. Treatments of artificial fertilization had a significant effect to W values of GK Öthalom in 2001 and 2002. The differences between the two methods are because of large standard deviation of the results. -
Evaluation of various silo sorghum hybrids from the energetic aspect
107-111Views:124The sweet sorghum is a perspective plant of bioenergy, which can be the foundation of Hungarian bioethanol production in the future. By the examination six sweet sorghum hybrids have been examinated by the viewpoint of sugar aggregation and bioethanol production capacity. The founda tion of the surve y was three growing se ason (201 0, 2011, 2012 ). The ex per ime nt w as on the production sites of U niversity of Debrecen CAAES RISF Karcag Research Institute. The production site of the sweet sorghum have been sampled by samples of 1 m2 by hybrids within the period of august 15 and november 15. The sugar content of the samples have been measured by refractometer which was the base in the determination of ethanol production capacity.
As a continuation of the evaluation of energetic viewpoint the Higher Heating Value (HHV) have been measured from the bagasse of sweet sorghums. According to the results it can be stated that int he case of sugarcontent and the dinamics of the sugar aggregation can show several differences, while HHV of sorghum bagasse is within 16 200 and 16 900 J g-1.
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Environmental Consequences of Efficient Use of Nitrogen Fertilizers
41-46Views:78Nitrogen fertilizer represents major economic burden. For this reason, although the efficiency of nitrogen utilization varies highly, its actual use generally remains at low levels; these averaging between 25 and 50%. We set up an experiment at the Oradea Research Station, using 15N labeled fertilizers, in order to investigate the possibility of increasing N fertilizer efficiency in winter wheat under irrigation conditions.
Fertilizers labeled with 15N allows us to individually determine its effect on yield formation, as well as the use efficiency of N from fertilizer following application rate and time. The amount of N derived from fertilizer as determined in straw and grain yield is high. When the labeled fertilizer is applied at tillering time, the values of this indicator rise when higher N levels we applied.
In separate experiments, we investigated a series of aspects connected to chemical fertilizer regarding the determination of the type of fertilizer, optimum time and rates of application; all these as a function of the special pedoclimatic conditions.
The results obtained in the field show that the effectiveness of N utilization in wheat is most variable and generally low, often ranging between 25 and 33%, owing to N loss within the system through leaching and NH3 volatilization.
A readily achievable increase in efficiency of 5 percentage points would result in considerable savings, and can be brought about by reducing nitrogen losses. The added benefits to the environment in terms of reduced ground/water contamination and lowered nitrous oxide (N20) emissions would also be substantial.
The figures for N fertilizer use efficiency (% N range from 35.5 to 72.6, the highest value being recorded with an N application of 120 kg/ha at tillering, when the previous crop was sunflower).
INTRODUCTION