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  • Author or Editor: E. Németh x
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Long-term N fertilization experiments were established with identical treatments at two different growing areas in Hungary: one on a calcareous sandy soil (Őrbottyán) and the other on a calcareous chernozem soil (Nagyhörcsök). The aim was to create differences in mineral-N content in the soil profiles in order to determine their N supplying capacity and to establish whether the accumulated nitrate may be regarded as a supply index for crop production. The results showed that under certain environmental conditions N may accumulate in the soil profile in the form of nitrate, resulting from N fertilization in previous years, to such an extent that it must be taken into consideration when determining the fertilizer rates to be applied. This is important not only from the point of view of economical management and environment protection, but also for reaching better yield quality. The calculations can be reliably performed if they are based on the measurement and calibration of the soil's mineral-N content. The environmental importance of such calibration experiments is that by estimating the utilization of N from the mineral-N pool, the additional costs incurred due to over-fertilization can be eliminated, and at the same time the potential danger of NO 3 leaching to the groundwater can be reduced. Extrapolation of the experimental results to farm scale can lead to both economical and environmental achievements.

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Achillea species have been traditionally utilized as raw material for tea mixtures and pharmaceutical preparations. The most important active agent of the drug is the essential oil which influences both the aroma and the effect of the tea. Most frequent monoterpene components of the oil are 1,8-cineole, camphor, borneol and α- and β-pinenes. Among sesquiterpene compounds, chamazulene, caryophyllene and oxides, as well as germacrene are to mention. Intrageneric and intraspecific chemical variability is a characteristic feature. Composition of the oil is highly variable, data on heritability are scarce. Differences in the oil composition have been detected in consequence of ontogenesis and organic differentiation. The influence of ecological factors (altitude, association, nutrients, etc.) seems to be an indirect one. Oils produced by different extraction methods, may show diverse composition.In the practice, variability of essential oil content and composition often degrades the quality of the raw materials for herbal teas. Solution may be development of agrotechnology and utilisation of standard cultivars.

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Preservative qualities of caraway, known from ancient times, have regained importance as 21st century food safety issues predominate. Essential oil content and its composition of annual caraway varies significantly when row spacing and nutrient supply are manipulated under experimental conditions. During 2006–2007, Carum carvi var. annua cultivar ‘SZK-1’ was sown in small plots in three replications with two factors in split plot design. The row spacings were 24 cm, 36 cm, and 48 cm, and six nutrient application rates were applied (Control, N0K80, N80K0, N80K80, N80+70K0, N80+70K80). The results show that the percentage of essential oil content is influenced by the row space. Furthermore, our data show that increased potassium level enhances the amount of d-carvone in the oil. Every treatment of potassium produced higher d-carvone levels (53.34%) than those found in the control. In 2006, the first year of the two-year study, the highest carvone level (66.25%) was measured in the treatment of N80+70K80, whereas in 2007 the highest level occurred in the N80K80 (49.216%) treatment.

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The present article discusses the applicability of thermoanalytical methods in the analysis of Hungarian soils formed on carbonate rocks. Up to now only limited mineralogical and soil chemical research has been done on these soils. Soils from the Bükk Mountains, the most varied limestone region in Hungary, were used for the investigations. The aim was to extend our incomplete knowledge on the mineral composition and formation processes of these soils and to demonstrate the possibilities and evaluation potential of thermoanalytical techniques. All the soils investigated were formed on limestone and had different surface soil thickness, influenced by the accumulation of silicate debris and the microterrain. The results of soil mineralogical analysis revealed an extraordinarily high proportion of quartz compared to that of other minerals (especially calcite), indicating that these soils could not have originated solely from the weathering of the limestone bedrock. The results also showed that thermoanalytical methods could complement classical chemical and instrumental (XRPD) methods in research on the genesis of soils formed on limestone.

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This paper introduces the alternating conditional expectation (ACE) algorithm of Breiman and Friedman (1985) in multiple regression problems in groundwater monitoring data analysis. This special inverse nonparametric approach can be applied easily for estimating the optimal transformations of different groundwater monitoring data from the Bükk Mountains to obtain maximum correlation between observed aquifer variables. The approach does not require a priori assumptions of a mathematical form, and the optimal transformations are derived solely based on the groundwater data set. The advantages and applicability of the proposed approach to solve different multiple regression problems in hydrogeology or in groundwater management are illustrated by means of case studies from a Hungarian karst aquifer. It is demonstrated that the ACE method has certain advantages in some fitting problems of groundwater science over the traditional multiple regression.In the past, different groundwater monitoring data (like groundwater level, groundwater temperature and conductance, etc.) had been used for groundwater management purposes in the Bükk Mountains. One of the difficulties in earlier approaches has been the need to make some kind of assumption of the expected mathematical forms among the investigated reservoir and petrophysical variables. By using nonparametric regression, the need to assume a specific form of model is avoided, and a clearer vision of the relationships between aquifer parameters can be revealed in the Bükk Mountains, where karst water is the main source of potable water supply. Complex monitoring data from the Bükk Mountains were analyzed using the ACE inverse method, and results were verified successfully against quantitative and qualitative field observations.

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Authors: E. Durszt, J. Németh and A. Varga

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Authors: R. Szőllősi, A. Medvegy, E. Benyes, A. Németh and E. Mihalik

Numerous experiments have suggested that in many species higher floral display can be more attractive for pollinators, but the possibility of between-flower self-pollination, namely geitonogamy may reduce the floral longevity, the fitness of both individuals and the offspring. In this study we investigated how phenological parameters (mainly floral display) change temporally and how they affect the female reproductive success of cymose Iris sibirica. We found that in blooming sequence of both individuals and the population 3 sections can be separated. The number of levels and flowers per stalks on the plants observed was very variable yearly. Female reproductive success parameters (fruit set and seed set) showed intra- and interannual variations, which were probably due to intra-plant resource allocation.

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Authors: E. Kovács, P. Merész, Z. Kristóf and E. Németh-Szerdahelyi

Colour, texture, pectin autolysis, membrane permeability and microstructure (SEM, TEM), β-galactosidase and polygalacturonase were studied in apricots (cv. Magyar kajszi) harvested in mature green, straw yellow, bright orange and deep orange stages. The L* increased from mature green to straw yellow then decreased from straw yellow to deep orange state. The a* values increased with ripening. The bright and deep orange apricots were significantly softer than the mature green and straw yellow ones and the membrane permeability increased with ripening. The presence of β-galactosidase enzyme was proved by immunoblotting analysis using monoclonal anti-β-galactosidase clone GAL-13 (Sigma) in all ripening stages. The enzyme activity was very low in mature green stage and increased significantly (P>95%) with increasing ripeness and during storage. The PG activity was very low in the mature green apricot. A significant (P>95%) increase was observed in the straw yellow apricot and in the riper fruits. The mature green apricot showed a regular, the straw yellow and bright orange samples showed a moderately regular tissue structure, while the tissue of the deep orange apricot collapsed (SEM). The cell wall and the middle lamella of the green apricot (TEM) were intact. Generally, there were intact cytoplasm membranes with some damaged parts. In the straw yellow apricot, the cell wall started to loosen, the middle lamella lost pectic polysaccharides. The structure of the cytoplasm was not recognisable, the tonoplast and the cytoplasm membrane were injured. The cell wall of the bright orange apricot was similar to that of the straw yellow ones. The middle lamella dissolved and hairy, fibrillar structure of cell wall was found in the deep orange samples.

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Authors: C. Farkas, A. Hagyó, E. Tóth, J. Szabó and T. Németh

This study was carried out to evaluate the soil hydrophysical properties and soil water regime of two irrigated maize fields in order to support irrigation planning and management. The experimental sites were located in Mezohegyes (MZH) and Hódmezovásárhely (HMV) in SE Hungary. In total 11 monitoring stations were chosen, using information from a previously developed, GIS-based agro-geoinformation system. In 2003 and 2004 soil sampling and in situ measurements were performed to determine the soil hydrophysical properties and soil water content dynamics. The hydraulic conductivity of the topsoil was evaluated from double ring infiltrometer measurements. A previously calibrated TDR 300 instrument and a 3T-M capacitance probe were used for quantifying the soil water content. Both types of equipment were found to require calibration and testing under field conditions before use. It was concluded that the study fields could be considered relatively homogeneous in relation to both soil hydrophysical properties and soil water regime. Thus, monitoring stations established for one or two carefully selected soil profiles could provide enough data to ensure proper decisions on irrigation. The results indicate that the soil management system and irrigation strategy used in the experimental fields ensured satisfactory soil and soil moisture conditions.

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Whole cereal flours (buckwheat, barley, and oat) and wheat bran were used to substitute 20% of white bakery wheat flour to prepare round rolls. Round roll quality was evaluated by determining total phenolic and total flavonoid contents, antioxidative capacity, the content of lipid hydroperoxides (primary oxidation products), and sensory profiling. Moreover, the stability of the phenolic compounds and antioxidant behaviour throughout processing was studied. Technological processing does not cause any significant loss of phenolics (less than 5%). A significant increase in antioxidants and phenolics of the flour mixtures and final products were observed compared to those of white wheat round rolls (as control). Buckwheat and barley round roll crumbs contained the highest total phenolic and total flavonoid contents, and were the most effective in enhancing antioxidant activity, which increased 15-fold and 8-fold, respectively, when compared to the control roll. The tested cereals effectively retarded formation of lipid hydroperoxides (from over 50% to control), which are undesirable from both a nutrition and storage/shelf life perspective. The results of sensory analyses showed that such bakery products are accepted by consumers with the exception of the product made with oat flour, where a reduction in the oat content would be preferable.

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