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  • Author or Editor: A. Németh x
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Pesticide producers cannot ignore their possible obligations under the REACH regulation controlling registration, evaluation and authorization of chemicals, as only the active ingredients (and not the other composites) are exempted from REACH requirements, and more specifically only those quantities of these substances, which are used for plant protection purposes. Registration requirements show similarities with the pesticide authorization process, moreover, the required ecotoxicological tests for pesticide active substances are of the same extent as in the case of industrial substances manufactured/imported in quantities of at least 100 tons per year. A further common characteristic is the higher legal level and more centralized feature of the regulations, leading to the establishment of different authorization zones within the European Union. Although this is considered a favorable trend in case of chemical substances from the aspect of the free movement of goods, possible benefits of zonification regarding pesticides are rather questionable due to the significant differences in ecological characteristics among different areas of the European Union. Studies on genotoxic and endocrine disrupting effects are challenging the fundamentals of toxicology. Conflicting results burden the treatment of endocrine disrupters; laying down the foundations of a testing framework, and legal regulation is still ongoing. Their controversial situation is demonstrated by a few examples.

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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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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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under the influence of the prognosticated climatic changes, the increasing rate of degradation and the extension of uncultivated lands, it is expected that the dominance of some C4 plants will increase. Bermuda grass (Cynodon dactylon) is the most common C4 species in Hungary. The chemical composition of Cynodon dactylon and its substrate was investigated on 3 soil types (Arenosol, Solonchak soil and a waste place) typical of the country. It was established that in comparison with other perennial C4 grasses (Andropogon ischaemum, Chrysopogon gryllus, Cleistogenes serotina) the total element content of Cynodon dactylon was the highest. A detailed quantitative and qualitative knowledge of the chemical components of C4 plants could help to determine the expected changes in the chemical composition of the uppermost soil layer and in its mineralization dynamics on areas dominated by these plants. As a result of the expansion of Cynodon dactylon the element concentration and the chemical composition of the soils might change, thus influencing successional processes as well.

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In December 2012 then in the following winter season, the occurrence of whitish mycelial coat was observed on the collar of 3- to 6-m high Bucida buceras trees grown in hydrocultures to decorate a spacious indoor community space in Vienna. (This plant [shown in Fig. 1] belongs to Combretaceae, Myrtales and commonly named black olive tree, bullet tree, gregorywood and oxhorn bucida.) The mycelium-infested area of the bark appeared to be water-soaked. Near the surface of the potting mix (earth ball embedded in clay pebbles), the roots were also covered with whitish mycelia (Fig. 2). Over the winter season when the indoor temperature increased from 20 °C to 25 °C, these symptoms were unnoticeable. Regardless of the season, the rhizosphere contained numbers of sclerotia, dark-grey, globose and 8–12 mm in diameter that occasionally developed rhizomorph-like mycelial cords.

Direct plating of mycelium fragments from the bark and sclerotia from the rhizosphere onto potato dextrose agar amended with ampicillin (500 mg/l) eventually yielded pure fungal cultures of similar characteristics. Cultures routinely incubated in the dark developed white and submerged colonies with sparse aerial mycelia. The fungus grew well between 10 °C and 25 °C, and failed to grow at either 5 °C or 32 °C. The optimal growth was measured at 20 °C with an average radial growth rate of 11 mm per day. After 10 to 12 days, a ring of sclerotia begun to develop near the edge of the colonies; they turned dark grey and sized 3–8 mm. Rather misleadingly, neither conidia, nor sexual spores were observed in these cultures. However, when the fungus was cultured in natural light under laboratory conditions at 25 °C, a completely different colony pattern was observed; it was cottony, greyish then dark grey, and produced abundant hyaline conidia borne on grey, branching tree-like conidiophores. Conidia were one-celled and egg-shaped, and their dimensions fell in the range of 9.89–14.63 (11.48±0.31) µm×7.05–10.05 (8.31±0.20) µm. These features concurred with those characterising the polyphagous grey mould fungus Botryotinia fuckeliana (anamorph: Botrytis cinerea) (Elad et al., 2007). The ITS1/ITS2 including the 5.8S subunit of rDNA of one of the isolates were amplified with primers ITS1-F/ITS4, then the PCR products were sequenced. The ITS sequence determined in this way was identical to known sequences of B. fuckeliana strains, e.g. that of CBS 131.28 (GenBank accession number: KF859918), the type material of Botrytis cinerea f. lini, DAOM 231372 (GenBank accession number: KF859924) and so on.

Pathogenicity tests resulted in rapidly (within 2 weeks) developing disease symptoms around the site of wound inoculation with a 5-mm-diametre mycelial agar plug: fruit rot on apple and lemon in the laboratory, and sunken lesions on stems of hydrocultured ornamental plants such as the herbaceous Monstera deliciosa and the woody Dracena marginata. To fulfill Koch’s postulates, the fungus was re-isolated from symptomatic apple fruit, and was found to exhibit the afore-mentioned morpho-physiological characteristics.

Inoculation test on Bucida was not performed because of the costly risk i.e., the sale price of the trees is € 3 to 10 thousand. Consequently, the actual sensitivity of Bucida to grey mould remains uncertain, so much the more because this plant species has not been recorded as a host of the pathogen or other important parasitic fungi in natural (subtropical) environment (e.g. Whelburg et al., 1975). To our knowledge, this report is the first description of Botryotinia fuckeliana on Bucida buceras. In addition to the fact that periodic emergence of fungal mycelia on the trunk impairs the tree’s aesthetic appearance, the sclerotia resting in the potting mix may cause more serious problems in the long term. However, it cannot be precluded that the elevated indoor temperature reduces disease progression and thus the economic importance of the pathogen on this plant.

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Amblyopia is a visual disorder caused by an anomalous early visual experience. It has been suggested that suppression of the visual input from the weaker eye might be a primary underlying mechanism of the amblyopic syndrome. However, it is still an unresolved question to what extent neural responses to the visual information coming from the amblyopic eye are suppressed during binocular viewing. To address this question we measured event-related potentials (ERP) to foveal face stimuli in amblyopic patients, both in monocular and binocular viewing conditions. The results revealed no difference in the amplitude and latency of early components of the ERP responses between the binocular and fellow eye stimulation. On the other hand, early ERP components were reduced and delayed in the case of monocular stimulation of the amblyopic eye as compared to the fellow eye stimulation or to binocular viewing. The magnitude of the amblyopic effect measured on the ERP amplitudes was comparable to that found on the fMRI responses in the fusiform face area using the same face stimuli and task conditions. Our findings showing that the amblyopic effects present on the early ERP components in the case of monocular stimulation are not manifested in the ERP responses during binocular viewing suggest that input from the amblyopic eye is completely suppressed already at the earliest stages of visual cortical processing when stimuli are viewed by both eyes.

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Cereal Research Communications
Authors: A. Mikulajová, D. Šedivá, M. Čertík, P. Gereková, K. Németh and E. Hybenová

Foxtail millet (Setaria italica) genotypes with red and yellow colour of grain bran were examined and compared for their content of nutritive components, fatty acids and phenolic compounds profile. Moreover, the antioxidant properties were investigated using three different methods. Foxtail millet genotypes contained 14.2% of protein, 5.0% of fat and 4.3% of soluble sugars, on average. Linoleic acid was the most abundant unsaturated fatty acid and palmitic acid was the most abundant saturated fatty acid. Four hydroxybenzoic acids (gallic, protocatechuic, vanillic and syringic acid) and two hydroxycinnamic acids (ferulic and p-coumaric acid) were identified and quantified. All genotypes exhibited effective inhibition of free radicals. Nevertheless, ferrous ion chelating activity was weak. Antioxidant properties of foxtail millet genotypes were closely associated with the presence of phenolics. A relationship between intensity of grain colour and antioxidant properties as well as phenolic compounds content, was observed. We can conclude that the content of evaluated parameters varied among foxtail millet genotypes, therefore their assessment and selection is desirable in order to cultivate crops and produce foods with advanced nutritional and antioxidant properties.

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Cereal Research Communications
Authors: G. Balázs, S. Tömösközi, A. Harasztos, V. Németh, Á. Tamás, A. Morgounov, I. Belan, W. Ma and F. Békés

Based on previous research on validating lab-on-a-chip data on wheat protein analysis, a comprehensive work has been carried out with the intent to demonstrate the potential of the technique for wheat related fundamental research, breeding and food industry. Sample preparation and separation methodologies were investigated for the main wheat polypeptide classes: albumins, globulins, gliadins and glutenin subunits (GS). The work was carried out on a sample population originated from Western Siberia with different genetic background providing data, and characterizing their potential interest for future breeding work. LOC results are compared with corresponding reference methods (MALDI-TOF and RP-HPLC). The research revealed that, the current technology is capable for fast profile analysis, recognizing the minor qualitative, and typical quantitative differences in the albumin and globulin protein composition. While the gliadin separation showed poor results, the method seems to be able to identify the high molecular glutenin allelic composition, and to differentiate some of the low molecular weight glutenin alleles, too. Our results provide new insights into a possible rapid and simple way for grain protein profiling.

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