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  • Author or Editor: G. Fekete x
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Some pedological and micromorphological investigations were carried out on representative red clay samples selected from a large number of profiles. On the basis of conclusions drawn from the analytical results, the red clays can be divided into the following groups: - The red clays of the foothills of the Tokaj Mountains were formed on rhyolite or rhyolite tuff, and are covered by loess in some areas. They are relic soils, older than loess, formed under the warm climate of the Tertiary Period. In addition to quartz they contain feldspars, illite, montmorillonite and a small amount of kaolinite. - The red clays of Aggtelek Karst are Tertiary relic soils formed on Mesozoic limestone. The dominant clay mineral is kaolinite, but they contain a siginificant amount of smectite as well. - The red clays of the Northern periphery of the Hungarian Plain are situated on clay, silt and sand layers of different origin or between loess depositions. They were formed in the Pliocene and at the turn of the Pliocene and Pleistocene. These soils have a medium clay content, with a large quantity of montmorillonite and a small amount of kaolinite. - Red clays formed on Permian sandstones . These rocks were formed in the Permian period, and were issued from a mixture of sediments under tropical climate, tropical weathering. They are the signs of the oldest soil formation in Hungary. They can be characterized by their kaolinite, illite, montmorillonite and hematite contents. - The red clays of the Transdanubian hilly region wereformed by the weathering of thePannonian surface between the end of the Miocene Period and the lower Pleistocene. Medium clay content is characteristic of these red clays. They contain kaolinite, montmorillonite, chlorite and a small amount of hematite. Concerning micromorphological features, speckled and granostriated b-fabrics of the groundmass, mainly due to swelling and shrinking, were observed in some samples. Clay coatings are mainly interpreted as micromorphological features of illuviation. The investigated red clays are similar to tropical and sub-tropical ferrallitic soils in respect of their formation and mineral characteristics.

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The objective of our study was to analyse the results of two measuring methods (sensory evaluation and electronic tongue) and to find differences in taste between grafted and non-grafted watermelon fruit. The trained sensory panel evaluated in two years three differently treated watermelon fruit. The studied fruit samples were produced on the same growing-areas in both years but with different growing technologies. The experiment used the non-grafted/self-rooted watermelon as control sample, while the other two treatments were grafting on two rootstock types: a Lagenaria and an interspecific squash hybrid rootstock. The electronic tongue measurement showed that it is the environment/growing technology that mainly determines the characteristics of the fruit quality, not grafting. The two measurement methods can complement each other in a detailed and practical way, as technology and growing area strongly influence the quality of watermelon fruit. The research also showed that it is possible to have similar watermelon fruit quality, independently from the used rootstock type.

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Fruits and vegetables are increasingly consumed as a part of healthy diets. They are routinely consumed raw, without any further antimicrobial processing. The aim of our studies was to determine radiation doses improving the microbial safety of fruits without diminishing quality parameters of these produce. Effects of low dose irradiation on the microbiota, antioxidant capacity, total polyphenol contents, firmness and sensory properties of pre-cut apple, orange and banana were investigated. Dose of 2.0 kGy was able to reduce considerably the microbiological contamination of fruits, apple, orange, banana, but microorganisms surviving the irradiation are able to recover and grow during refrigerated storage. Two kGy was an acceptable radiation dose for the treatment of these products, having no significant effect on the mentioned quality parameters.

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A new liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed to confirm chloramphenicol (CAP) residues in foods of animal origin and in urine samples, which were earlier found positive under the screening analysis, performed by competitive enzyme-linked immunoassay (ELISA) technique. The developed LC-MS/MS method was applied to four non-compliant samples from 2008 to 2012; giving concentrations of CAP residues from 1.18 to 3.68 μg kg−1. All samples, qualified positive by ELISA, were confirmed with the LC-MS/MS technique and found to be non-compliant. The effectiveness of the confirmatory method was proven by participating in a successful proficiency test in year 2010. Both LC-MS/MS and ELISA methods were validated according to the European Union 2002/657/EC decision. The decision limit of the confirmatory method was determined as 0.02 μg kg−1 for CAP in each validated matrix, while the detection capability of the screening test was 0.15 μg kg−1.

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Abstract

This study aims to predict drought periods affecting the Tokaj-Hegyalja wine region and the application of this in crop protection. The Tokaj-Hegyalja wine region is the only closed wine region in Hungary with a specific mesoclimate and a corresponding wine grape variety composition, in which climate change strongly threatens cultivation. The probability that a randomly selected day in the vegetation period will fall into a drought period in the future was estimated using the daily precipitation amount and daily maximum temperature data from the Hungarian Meteorological Service for the period 2002–2020. The Markov model, a relatively new mathematical method for the statistical investigation of weather phenomena, was used for this. Markov chains can, therefore, be a valuable tool for organizing integrated pest management. This can be used to plan irrigation, control fungal pathogens infecting the vines, and plan the success of a given vintage.

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