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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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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 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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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 aim of the experiments was to develop translocation lines by inducing homoeologous chromosome pairing in a 4H(4D) wheat-barley substitution line previously developed in Martonvásár. It was hoped to incorporate various segments of the barley 4H chromosome from the 4H(4D) substitution into wheat. Observations were made on the frequency with which wheat-barley translocations appeared in the F 2 progeny grains from a cross between the line CO4-1, which carries the Ph suppressor gene from Aegilops speltoides and thus induces a high level of homoeologous chromosome pairing, and the 4H(4D) wheat-barley substitution line, and on which chromosome segments were involved in the translocations. The translocations were identified by means of genomic in situ hybridisation. Of the 117 plants examined, three (2.4 %) were found to contain translocations. A total of four translocations were observed, as one plant contained two different translocations. The translocations consisted of one centric fusion, two dicentric translocations and one acrocentric chromosome. Plants carrying translocations were raised in the phytotron and the selection of homozygous translocation lines was commenced from the F 3 progeny grains.

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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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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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Cultivated einkorn (Triticum monococcum L. ssp. monococcum) is an excellent source of resistance against several wheat diseases and quality parameters. Semi-dwarf einkorn lines with good crossability were identified in order to produce Triticum turgidum × T. monococcum synthetic amphiploids. Two combinations were used to develop the amphiploids: durum × einkorn and emmer × einkorn.After the genome duplication of F1 seeds, highly fertile amphiploids were developed. The AuBAm genome structure of the progenies was confirmed by genomic in situ hybridization (GISH).Lines derived from durum × einkorn and emmer × einkorn crosses were studied for agronomic performance, disease resistance and genetic variability. Both amphiploid combinations showed excellent resistance against certain wheat diseases (leaf rust, powdery mildew), but not against fusarium. The durum-based synthetic amphiploid lines showed a higher level of phenotypic diversity. The newly produced T. turgidum × T. monococcum synthetic hexaploids are promising genetic resources for wheat breeding. Selected durum × einkorn lines are currently used in bread wheat improvement to transfer the useful properties of einkorn into cultivated hexaploid wheat via ‘bridge-crossing’.

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