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In this study we examined the proline content of 143 honey samples with different flower origin. Some of the samples originated from commercial trade, the others came directly from beekeepers. We measured the proline content of beekeepers’ honeys and the received results were compared to the results of commercial honeys. The effects of added sugar products and heating on the quality parameters were also studied.

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The rheological properties of seven winter wheat cultivars from two harvest years were studied. Rheological testing included two empirical rheological methods, alveograph and extensograph. Principal component analysis on the studied rheological parameters showed that the alveograph and extensograph parameters are influenced by entirely different factors. The first component was responsible solely for the extensograph parameters, primarily for the resistance properties of dough samples. The second component affected the extensograph extensibility (E) and alveograph tenacity (P) parameters as well, in spite of the fact that these parameters refer to different properties of dough. The third component explained only alveograph parameters, such as P, L and G values. The Pearson’s correlation coefficients showed that the extensograph area parameter primarily depends on the maximum resistance to extension of dough (r=0.91). The extensibility and resistance at a constant extension of 5 cm properties did not show such strong relationship with the area parameter (r=0.56 and 0.65, respectively). The relationship between the extensograph maximum resistance and extensibility parameters was positive (r=0.20), while the correlation coefficient between alveograph P and L value was negative (r=0.34).

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The aim of the study was to investigate changes of photosynthetic efficiency, amount of photosynthetic pigments, superoxide dismutase (SOD) enzyme activity, and rate of lipid peroxidation in bean-rust interaction. The clarification of the role of the above changes involved in the defence mechanism can significantly contribute to the breeding of plant varieties with natural resistance. Consequently, the amount of chemicals used in food production can be significantly reduced. In the present study some principal physiological parameters, such as the relative chlorophyll content of the host plant, the amount of photosynthetic pigments, changes in photosynthetic efficiency, and the activity of superoxide-dismutase (SOD) in addition to rate of lipid peroxidation (LP) were measured. The experiment was conducted in a humidity tent. Significant decrease in the relative chlorophyll content and in the amount of photosynthetic pigments was measured. At both sampling times, an increase was found in superoxide-dismutase enzyme activity and in rate of lipid peroxidation due to the bean rust infection. Notably, in several cases the differences were significant. The results indicate that the above parameters have important role in the bean-rust interaction, which should be taken into consideration in resistance breeding.

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Agricultural goods obtained and produced in Hungary have played an important role in the markets of Western Europe. By utilizing the ecological potentials of the Carpathian Basin, local inhabitants are in the position to produce considerable food surpluses in addition to meeting their own demands. With agricultural production becoming more and more intensive in Hungary, the application of mineral fertilizers also started to increase slowly from the 1960’s. From the mid-1970’s a uniform sampling, soil testing and fertilization extension system was created together with its own institutional and laboratory testing network. The intensive use of mineral fertilizers in Hungary lasted from the mid-1970’s to the last quarter of the 1980’s, during which an average amount of 230 kg·ha -1 NPK fertilizer was applied. In this period the so-called “build-up” fertilization was applied in conformity with the improvement of all other elements involved in the production technology, which was also clearly expressed in the agro-political objectives of those days aiming to obtain higher yields. At that time the nutrient supply and nutrient base of soils in Hungary increased clearly, so the production technology could no longer limit higher yields. In 1990 agriculture changed fundamentally and radically in Hungary, and the same was valid for nutrient supplies as well. At the beginning of the 1990’s there was a sudden decrease in the level of mineral fertilizer application (to below 40 kg NPK active ingredients·ha -1 ), followed by a slow increase, which has reached the level of almost 70 kg·ha -1 by today. In the meantime the animal stock in Hungary has decreased and consequently the amount of manure has also fallen. All in all, the nutrient balance of Hungarian soils has always been negative since 1989. Due to the changes in its structure and ownership over the past twenty years or so, it has become very difficult to obtain reliable information about Hungarian agriculture. The Soil Resources Management General Partnership (in Hungarian: Talajerőgazdálkodás Kkt.) conducts extension work based on soil sampling and has a continuous flow of data on over thirty thousand hectares, beginning at the end of the 1970’s. Based on the analyses of these data it can be stated that the extra amount of nutrients over balance, applied during the period of replenishment (until the change in regimes) has been „removed” from the soil over the past fifteen years, consequently the Hungarian nutrient balance has become negative again. This kind of fertilization practice cannot be sustained in Hungary, as the maintenance of the production potential of Hungarian soils is far from being resolved at the moment; it poses risks to and questions sustainability, as well as it may cause a very serious competitive disadvantage to the country.

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A normalization method was tested for the detection of low level chromium contamination in the soil of the Tisza River Floodplain in Hungary. The soils' so-called “total” metal concentration (strong acid extractable fraction) is the basis of many environmental evaluation methods, soil tests.  In the floodplain soils cadmium, lead, zinc and copper occur in elevated concentrations, but their chromium concentration is not significantly higher than that of the control soils.  The normalization method makes it possible to calculate the anthropogenic and geogenic chromium concentration in soil. Anthropogenic chromium was not detectable on the control sites, but a significant amount (4-14 mg/kg) was found in the floodplain soil samples. The applied normalization method proved the low level chromium contamination in the floodplain.

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At the beginning of the year 2000 two considerable waves of pollution occurred on the river Tisza. With the second wave, in a simultaneous flood, a huge amount of mud contaminated with heavy metals settled on the floodplains. As most of the contaminated areas are under agricultural use, the study of the heavy metal charge of soils and herbaceous plants of the floodplain has great importance. Along the Tisza four sampling sites were established and 300 cm deep drill cores were taken. The results of analytical examinations show that the heavy metal content of the topsoil is higher than that of the earlier formed lower layers, although contamination is also present there. This suggests that pollutions like this are not unknown in the Tisza Valley. It is greatly important to take cadmium pollution into consideration, as this element is extremely toxic and easily taken up by plants, and is likely to be a serious problem in the floodplain. The risk of contamination in the topsoil of the floodplain soils were examined in detail. The soils’ heavy metal content was the highest where the two pollution waves can be measured first at the same site. For determining the amount of heavy metals bound to other compounds sequential extractions were carried out. The proportion of the water soluble and exchangeable fraction – that is bioavailable to plants – is negligible in respect of Cu, Pb, and Zn, while it is considerable in the case of Cd, showing the risk of contamination. The gained data show that the high proportion of cadmium results in a remarkable environmental risk, while other heavy metals turn into a bioavailable form only after intensive acidification. The proportion of the heavy metal fraction bound to humus materials was expected to be low due to the exogenous origin and freshness of the topsoil.

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