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The multicolour genomic in situ hybridization (mcGISH) method was improved in order to visualize the U b and M b genomes of Aegilops biuncialis Vis. (2n=4x=28, U b U b M b M b ). Hybridization probes prepared from the diploid U and M genome donors, Ae. umbellulata and Ae. comosa , resulted in clear hybridization signals on the U and M chromosomes in Ae. biuncialis . The random primed labelling method made it possible to decrease the blocking ratio to 1:30. McGISH allowed the simultaneous discrimination of individual Ae. biuncialis genomes and wheat chromosomes in γ-irradiated Triticum aestivum-Ae. biuncialis amphiploids (2n=70; AABBDDU b U b M b M b ). Dicentric chromosomes, terminal and interstitial translocations and centric fusions were detected in the irradiated generation. The irradiation-induced wheat- Ae. biuncialis intergenomic translocations will facilitate the successful introgression of useful agronomic traits into bread wheat.

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One way of incorporating useful traits from Aegilops biuncialis (2n=4x=28, U b U b M b M b ) into wheat ( Triticum aestivum L. 2n=6x=42, AABBDD) is to develop first addition then translocation lines. The 2M b , 3M b , 7M b , 3U b , 5U b and 5U b /6U b wheat- Ae. biuncialis addition lines were produced in Martonvásár. To facilitate the exact identification of the addition lines, it was necessary to analyse the fluorescence in situ hybridisation patterns of the parental wheat genotype, Ae. biuncialis and its diploid progenitors ( Ae. umbellulata 2n=2x=14, UU and Ae. comosa 2n=2x=14, MM). The great genetic variability of the Aegilops species causes polymorphism in the fluorescence in situ hybridisation (FISH) patterns of the individual chromosomes. Due to the high level of FISH polymorphism, it is advisable to confirm the identification of the Ae. biuncialis chromosomes with the help of molecular (microsatellite, SSR) markers, so 119 wheat SSR markers were tested on Aegilops biuncialis , on Ae. geniculata (2n=4x=28, U g U g M g M g ), on five wheat- Ae. biuncialis addition lines (2M b , 3M b , 7M b , 3U b , 5U b ) and on an addition series of wheat- Ae. geniculata in order to select SSR markers specific to the U and M genomes of Ae. biuncialis and Ae. geniculata .

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Each of the 7 Coxeter space groups in BE3 can be extended by the possible symmetries of its fundamental domain. Thus, we get a space group G in the title. For any orbit type (Wyckoff position) of G the optimal ball packing and its D-V cell have been determined, described and enumerated in tables and figures. We make a complete list for all the orbit types of the 29 generalized Coxeter space groups above.

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The aim of the present study was to test the efficiency of gamma irradiation in inducing translocations between wheat and barley genomes using addition lines. The Martonvásári 9 kr1-Igri disomic addition set, previously produced in Martonvásár, was irradiated with gamma rays. The pattern of irradiation-induced intergenomic chromosome rearrangements was analysed in the mutagenized (M0) generation by genomic in situ hybridization (GISH). Centric fusions and a wide variety of reciprocal, terminal and interstitial translocations were frequently induced. The intergeneric translocations produced here are expected to be stabilized in later backcross progenies as a set of introgression lines carrying few but distinct rearrangements.

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The photosynthetic responses induced by NaCl were investigated in the 7H Asakaze komugi/Manas wheat/barley addition line developed in the Agricultural Research Institute, Martonvásár, Hungary, in the wheat (Triticum aestivum L.) cv. Asakaze komugi (Akom) and wheat line Martonvásári 9 kr1 (Mv9kr1) and in the barley (Hordeum vulgare L.) cv. Manas. An increase in the NaCl concentration of the nutrient solution to 200 mmol L−1 resulted in considerable stomatal closure and a decreased net CO2 assimilation rate (A) in the wheat genotypes, while the changes in these parameters were less significant for barley and the 7H addition line. Parallel with this, a relatively high non-stomatal limitation (L m) of A was observed in wheat genotypes, which was not significant in Manas or the wheat-barley addition line at this level of salt stress. At severe stress (300 mM L−1 NaCl concentration) A and stomatal conductance were strongly inhibited in all the genotypes examined; however, L m was less significant in the addition line and its parental wheat genotype. These preliminary results suggest that the 7H Akom/Manas addition line might be a good candidate for improving the salt tolerance of wheat in the future, and encourage further detailed physiological analysis of this addition line.

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Biome interfaces are expected to exhibit chorological symmetry, i.e., decreasing trends in the number of species associated with each of the two neighbouring biomes as we progress from one into the other. Our aim was to test for such a pattern within the forest steppe biome, which is a transition zone in itself between the temperate deciduous forests and the steppe biome. Presence of chorological symmetry would provide indirect evidence for the prehuman presence of zonal steppes in the Carpathian basin. We also whished to provide an example with this analysis for drawing biogeographical conclusions based on quantitative species occurrence data, an information source hitherto neglected in Central Europe. Occurrence patterns of forest and steppe species were analysed at the Duna-Tisza köze (Danube-Tisza Interfluve) by the traditional qualitative biogeographic method and by hierarchical classification of predicted spatial pattern based on Generalized Linear Models with logistic link function. Species presences were explained by variables describing spatial orientation. In this approach, an outgroup of sand grassland species was also added to characetrise the discrimination ability of the approach. The quantitative method discriminated the out-group of sand grassland species, providing evidence of its suitability for our purpose. The results of the quantitative investigations were also in accordance with the qualitative evaluation. Surprisingly, forest and steppe species showed similar distributional patterns, i.e., no chorological symmetry was discernable. The quantitative biogeographic approach unveiled important evidence for deciding about the potential presence of zonal steppes in the Carpathian basin. Although the observed similarity of the distribution of forest and steppe species may have multiple reasons, the major cause of the lack of chorological symmetry is most probably the lack of zonal steppe South of the forest steppe biome in the Carpathian basin. Additional explanations include land use pattern and the mountain belt around the basin acting as a refugium in the ice ages.

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The drought stress tolerance of three accessions of Aegilops biuncialis Vis. (Ae225, Ae550 and Ae1050) and two varieties of Triticum aestivum L. (Sakha and Cappelle Desprez) was compared. The activity of superoxide dismutase (SOD) isoenzymes, which reflects the intensity of oxidative stress, changes in the malonic dialdehyde (MDA) content, formed during the lipid peroxidation induced by stress situations, and the inducibility of electron removal systems appearing as an alternative to CO 2 fixation were chosen for the present investigations. Drought stress was simulated using polyethylene glycol (PEG). The order of drought stress tolerance obtained correlated well with the original habitats ofthe varieties. The present results provide a clear illustration of the fact that tolerant varieties respond differently for the parameters tested, suggesting that their resistance can be attributed to different mechanisms. Abbreviations:CuZnSOD=superoxide dismutase isoform with Cu and Zn cofactor metals, MnSOD and FeSOD=superoxide dismutase isoform with Mn and Fe cofactor metals, PVP25= polyvinyl pyrrolidone 25, MDA=malonic dialdehyde, PEG=polyethylene glycol, TCA=trichloro acetic acid, TBA=thiobarbituric acid, ΔF=F m -F s , F m =maximal fluorescence yield, F s =fluorescence yield in steady state

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Acta Alimentaria
Authors: K. Molnár, M. Melles, I. Rodler, D. Stefler and I. Ember

In year 2006, unusual clustering of cases caused by calicivirus was reported from several EU member states (Germany, Netherlands, Denmark, Ireland, Finland, Norway). Various foods (raw vegetables, fruits, cultivated shells, etc.) may be contaminated at the location of cultivation; this is called primary contamination. Secondary contamination is when infected persons transmit the virus to the foods (e.g. bakery products) with contaminated hands.In Hungary the year 2006 was definitely the year of calicivirus outbreaks, the majority of which were detected in hospitals, elderly homes and children communities. The number and prevalence of outbreaks showed relatively high difference by counties. The outbreaks confirmed our conviction that without suitable and available laboratory methodology the agent could remain unknown. Furthermore, a general and controlled surveillance system is needed, which enables the rapid detection and elimination of gastrointestinal outbreaks of viral origin in collaboration with adequate laboratories.

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Triticum monococcum represents an important source of useful genes and alleles that it would be desirable to use in wheat breeding programmes. The well-defined landmarks on the Am chromosomes could accelerate the targeted introgression of T. monococcum chromatin into the wheat genome.Fluorescence in situ hybridization (FISH) using the repetitive DNA probes pSc119.2, Afa family and pTa71 showed that the pSc119.2 probe was not suitable for the identification of Am chromosomes. In contrast, the whole set of Am chromosomes (especially chromosomes 1, 4, 5 and 7) could be discriminated based on the hybridization pattern of pTa71 and Afa family. In situ hybridization with microsatellite motifs (GAA, CAG, AAC and AGG) proved that SSRs represent additional landmarks for the identification of Am chromosomes. The most promising SSR probes were the GAA and CAG motifs, which clearly discriminated the 6Am chromosome and, when used in combination with the Afa family and pTa71 probes, allowed the whole set of Am chromosomes to be reliably identified.In conclusion, fluorescence in situ hybridization using the repetitive DNA probes Afa family and pTa71, combined with SSR probes, makes it possible to identify the Am chromosomes of T. monococcum and to discriminate them from Au chromosomes in the polyploid wheat background.

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