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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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Abstract  

Detailed investigations were carried out to study the distribution of trace and minor elements in different parts (fruit, seed and rib, peduncle, stem, leaf, root) of ripe Hungarian spice paprika plants. Two varieties of paprika plants were analyzed for their Cl, Co, Fe, K, Mg, Mn, Na, Rb, Sc, V and Zn content by non-destructive neutron activation analysis. The results showed that the iron contents of the samples were much higher than those of the other trace elements. For the trace elements Co, Fe, Mn, Sc, V and Zn a considerable enrichment was observed in the leaf, while the Rb and K, Na, Mg showed accumulation mainly in the peduncle. In the other parts (fruit, seed and rib, stem) of the paprika plants no significant enrichment of trace elements was found. Since some of the elements investigated may have been partially eluted during the cleaning of the roots with distilled water and, on the other hand, if the cleaning was not intensive enough, some soil particles could be retained on the samples, the data obtained for the roots should be considered with precaution.

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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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Acta Alimentaria
Authors:
Zs. Molnár
,
Sz. Bánvölgyi
,
Á. Kozák
,
I. Kiss
,
E. Békássy-Molnár
, and
Gy. Vatai

Concentration of raspberry (Rubus idaeus L.) juice by combination of membrane processes was investigated. The pre-treatment steps were crushing, enzyme treatment, pressing and clarification by microfiltration (MF). Ceramic tube MF membrane was used at low pressure and temperature (3.9 bar and 30 °C).Nanofiltration (NF) and reverse osmosis (RO) process with flatsheet membranes was studied to pre-concentrate the clarified and sterilized raspberry juice. The NF experiments were carried out at different flow-rates (400 l h−1 and 600 l h−1). Any significant effect of flow-rate was not experienced. Both pre-concentration processes were used at low temperature (30 °C) for a mild concentration of raspberry juice. For further concentration osmotic distillation (OD) was applied. The initial total soluble solid content of the raspberry juice was 8–10 °Brix, the final concentrate of OD was 70–80 °Brix.The membrane-, fouling- and the polarization layer resistance were determined in case of micro-, nanofiltration and reverse osmosis.The soft drinks, made from RO and OD concentrates, were compared with well-known conventional raspberry juice from trade. During the sensory analysis (the colour, odour, flavour, acid taste and general impression was evaluated) our juices were preferred by customers.The antioxidant capacity, total phenol, anthocyanin and acid content, the total cell count and the number of yeasts and moulds were determined in the permeate and retentate samples of the different filtration steps.

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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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Sepsis-associated encephalopathy is a multifactorially determined process of the brain parenchyma. Among other factors, vasogenic causes have been shown to play a role in its development. The aim of the present work was to assess whether cerebral tissue oxygen saturation is influenced by administration of acetazolamide in septic patients compared to controls.

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The teratogenic effects of lead acetate (Trial 1) and the possible teratogenic effect of this compound administered in combination with a fungicide containing 80% mancozeb (Trial 2) were studied in rats. The test substances were administered by gavage on Days 6-15 of gestation. In Trial 1, five groups were treated with lead acetate administered at doses of 0.1, 0.5, 1.0, 10.0 and 1000.0 mg/kg body weight (bwkg), respectively. In Trial 2, lead acetate was applied at doses of 0.1, 10.0 and 1000.0 mg/bwkg, respectively. In the latter case the dose of the pesticide was 750 mg/bwkg in all treated groups. Lead acetate was not teratogenic after a single administration. Combined administration of lead acetate and mancozeb gave rise to the following toxic effects: average maternal weight decreased during pregnancy, the ratio of live fetuses decreased after the two lowest doses, and fetal mortality increased in the lowest and in the highest dose groups. The ratio of fetal resorption was higher in all the treated groups than in the control group. A significant decrease occurred in average fetal and placental weight in each treated group as compared to the control. Maternal toxicity was expressed in paralysis of the hindlimbs in the two lowest dose groups. Maternal mortality was between 16.7 and 23.3% at the three dose levels. Phocomelia and hernia cerebri occurred as characteristic fetal developmental anomalies in all the treated groups. It is concluded that the joint administration of lead acetate and a mancozeb-containing fungicide can cause maternal toxicity, embryotoxicity and characteristic teratogenic effects.

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The bulk formation of yeast-like (arthrospore-like) cells were typical in carbon-depleted submerged cultures of the high β-lactam producer Penicillium chrysogenum NCAIM 00237 strain independently of the nitrogen-content of the culture medium. This morphogenetic switch was still quite common in carbonstarving cultures of the low-penicillin-producer strain P. chrysogenum ATCC 28089 (Wis 54-1255) when the nitrogen-content of the medium was low but was a very rare event in wild-type P. chrysogenum cultures. The mycelium→yeast-like cell transition correlated well with a relatively high glutathione concentration and a reductive glutathione/glutathione disulfite (GSH/GSSG) redox balance in autolysing cultures, which was a consequence of industrial strain development. Paradoxically, the development of high β-lactam productivity resulted in a high intracellular GSH level and, concomitantly, in an increased γ-glutamyltranspeptidase (i.e. GSH-decomposing) activity in the autolytic phase of growth of P. chrysogenum NCAIM 00237. The hypothesized causal connection between GSH metabolism and cell morphology, if verified, may help us in future metabolic engineering of industrially important filamentous fungi.

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The purpose of this work was to determine the individual and combined effects of insecticide Sumithion 50 EC (50% fenitrothion) and herbicide Fusilade S (12.5% fluazifop-P-butyl) on the development of pheasant embryos. Eggs were treated by injection of various concentrations of pesticides into the air space on day 12 of incubation. Pathological examination of embryos was carried out on day 23 of the hatching period. Mortality rate, body weight data and morphological alterations were evaluated after the macroscopic examination. The skeletal staining method was used to detect deformities. The two pesticides used in combination moderated the toxic/teratogenic effects of individual treatment.

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A key driver of biodiversity loss is human landscape transformation. Change detection and trajectory analysis are frequently applied methods for studying landscape change. We studied to what degree habitat-specific change detection and trajectory analysis provide different information on landscape change compared to the analysis with land-cover statistics. Our research was carried out at two spatial scales (regional, 1800 km2, 360 random points; local, 23 km2, polygon-based maps) in the Kiskunság, Hungary. Spatio-temporal databases were prepared using historical maps, aerial photos and satellite images from 1783, 1883, 1954, and 2009. Local expert knowledge of landscape history and recent vegetation was used during the historical reconstructions. We found large differences at both scales between land-cover based and habitat-specific analyses. Habitat-specific change detection revealed that grassland loss was not continuous in the different habitats, as land-cover based analysis implied. Ploughing affected open sand grasslands and sand steppes differently in the periods studied. It was only apparent from the habitat-specific analyses that from the grasslands only mesotrophic and Molinia meadows were relatively constant, up until the 1950s. The gradual increase in forest area revealed by land-cover CHD analyses was split into natural and anthropogenic processes by habitat-specific analyses. Habitat specific trajectory analysis also revealed ecologically important historical differences between habitats. Afforestation affected especially the open sand grasslands, whereas wetland habitats were relatively stable. The most important trajectory was the one in which closed sand steppes were ploughed during the 19th century, and remained arable fields until present. Fifty percent of the regional trajectories of 18th century open sand grasslands terminated in tree plantations at present, though 82% of the current open sand grasslands of the local site can be regarded as ancient. We concluded that dividing land-cover categories into finer habitat categories offered an opportunity for a more precise historical analysis of key habitats, and could reveal important ecological processes that cannot be reconstructed with land-cover based analyses. It also highlighted habitat-specific processes making natural and social drivers better interpretable. Information on the diversity of habitat-histories may serve as a basis for spatially more explicit conservation management.

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