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Species-specific PCR assay was used to monitor endophytic colonization of maize by F. proliferatum. The fungus could be detected in all parts of one-week-old seedlings, grown in artificially infected soil indicating that F. proliferatum entered into the host tissues during germination. However, the extent of colonization gradually decreased and by the third week no signs of infection were detected in any part of the plants. These findings confirmed that F. proliferatum is a weak pathogen of maize and the damage reportedly caused by this species originates from horizontal transmission of the fungus rather than from an unbalanced endophytic interaction.

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In a long-term fertilization field experiment set up in Debrecen-Látókép in 1983 on calcareous chernozem soil the changes in the chemical and microbiological characteristics related to the carbon and nitrogen cycles of the soil are shown and evaluated. The soil samples were taken in the 26th and 27th years of the experiment, (in 2009, 2010) from maize monoculture and tri-culture. In addition to the effects of fertilizer doses, correlations among soil chemical and microbiological properties were established; and the various ratios among some microbiological parameters were also evaluated.The elements of NPK fertilizers increased together with the doses, so the elements’ effect cannot be separated, the minimum factor is not identifiable.With increasing fertilizer doses, the soil pH decreased in both the mono- and triculture, parallelly there was a significant increase in hydrolytic acidity. A close negative correlation was proved between the pH(H2O) and hydrolytic acidity and pH(KCl) and hydrolytic acidity. An increased soil nutrient content was recorded in each NPK treatment, the available phosphorus and nitrate content increased in a higher proportion than that of potassium.Among the measured parameters of the carbon and nitrogen cycles fertilization had a positive influence on the organic carbon (OC), organic nitrogen (ON), microbial biomass carbon (MBC), microbial biomass nitrogen (MBN) contents, the number of cellulose decomposing and nitrifying bacteria, the nitrate exploration and CO2-production, while it mainly had negative effects on the investigated enzymes (saccharase and urease) activity.Evaluating the ratios among the measured parameters, fertilization seems to have promoted the increase in nitrogen-containing organic compounds, because the OC/ON and MBC/MBN ratios decreased due to the effect of different doses of NPK fertilizers in both cultures.

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The biotic and abiotic stresses are the major limiting factors in plant productivity. To overcome these difficulties molecular breeding methods have recently been widely used to improve the stress and disease resistance of grapevine cultivars. Crown gall disease caused by Agrobacterium vitis or Agrobacterium tumefaciens causes serious damage worldwide on grapevine, and there is no efficient method yet that can be routinely used by grape-growers to prevent this disease. Therefore genetic manipulation for crown gall resistance would have a great economic impact. To this end embryogenic culture of Vitis berlandieri × Vitis rupestris cv. Richter 110 was transformed with a virE1 gene construct. Twenty-six plant lines were selected, and their transgenic nature was confirmed by PCR analysis. Seventeen of the 26 lines showed resistance to crown gall disease following inoculation with A. vitis Tm4 strain.

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To raise the efficiency of plant regeneration we studied the important and necessary elements of the procedure. The embryogen capacity of 33 various grape genotypes were tested on four different induction media. We successfully obtained anther derived embryogenic calli in 27 genotypes with the range of 1–12%, this is the first reported protocol for embryogenesis from Korai bíbor, Odysseus, Orpheus and Pannon frankos cultivars. Two sorts of sterilization treatments were examined before inducing somatic embryos. For optimisation of grape regeneration system the propagation of calli was attempted in Richter 110 cultivar, there was no any significant differences in the measured values, but CPE medium proved more successful in maintaining embryogenic capacity of callus. We experienced high developmental differences between the propagated embryogenic culture of Richter 110, Teleki 5C and Chardonnay derived from MSNOA liquid medium and from MSE solid medium. Regenerated plants from embryogenic callus were obtained in 21 genotypes, in Chardonnay cultivar CP medium influenced more positively the plant regeneration than the MS/2 medium.

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In a pot experiment the effect of bentonite and zeolite doses [0; 5; 10; 15 and 20 g·kg soil -1 ] was studied on some chemical properties and ten soil microbiological and enzymological properties of an acidic [pH(H 2 O) = 5.65] humic sandy soil [WRB: Lamellic Arenosol (Dystric)], as well as on the biomass of perennial ryegrass ( Lolium perenne L.), as test plant. The pot experiment was set up in 2007 and 2008 at the Department of Agrochemistry and Soil Science of the Debrecen University in three replications. The average results of the two year experiment can be summarized as follows: The pH increased due to the effect of small and medium amendment doses. The bentonite treatments proved to be more effective than the zeolite doses. As the pH increased, the hydrolytic acidity – in case of the bentonite treatments significantly – decreased. Concerning the easily available nutrient content of soil, the small and medium amendment doses turned out to be effective. The large bentonite doses reduced the nitrate-N content, the easily available phosphorus and potassium contents of soil. Large dose zeolite treatments decreased the nitrate-N content, but increased both the phosphorus and potassium content of soil, in most cases significantly. Regarding the measured soil microbial parameters, the small and medium amendment doses were the most effective. The bentonite and zeolite treatments increased the biomass of perennial ryegrass, especially the small and medium doses of bentonite and the large dose of zeolite brought about significant increases. According to the statistical analyses moderate and close correlations were found between the parameters studied. In the bentonite treatments a close correlation was established between the aerobic cellulose decomposing bacteria and saccharase enzyme activity (r = 0.864) of soil. In the case of zeolite treatments, a close correlation was found between the number of nitrifying bacteria and microbial biomass C (r = 0.911) of soil.

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Summary

A new liquid chromatography tandem mass spectrometry (LC-MS/MS) assay for the quantification of seven isoflavones (daidzin, genistin, ononin, daidzein, glycitein, genistein, and formononetin) and coumestrol in vegetable extracts was developed. The separation was performed on a Zorbax SB-C18 column with a mixture of methanol (solvent A) and 0.1% (υ/υ) acetic acid in water (solvent B) under gradient conditions at 50°C with a flow rate of 1 mL min−1. The detection of analytes was performed by electrospray ionization, negative ionisation, in non-reactive MS2 mode for aglycons or in reactive MS2 mode for glycosides. The method shows a good linearity (r 2 > 0.9948) over the concentration range of 40–4000 ng mL−1 for all analytes, a good precision (CV < 11%) and accuracy (<10%). The method was successfully applied to quantify the isoflavones and coumestrol in vegetable extracts obtained from red clover (Trifolium pratense L., Fabaceae) and dyer's greenweed (Genista tinctoria L., Fabaceae) and can be used in the chemical characterization of vegetables with phytoestrogen content.

Open access
Acta Veterinaria Hungarica
Authors:
N. Nagy
,
B. Igyártó
,
A. Magyar
,
Emese Gazdag
,
V. Palya
, and
I. Oláh

The oesophageal tonsil of the chicken is a novel member of the mucosal-associated lymphoid tissue (MALT), which is located around the entrance of the proventriculus. It consists of 6 to 8 single units, which are surrounded by a thin fibrous capsule. Each one is organised around the bottom of the longitudinal folds of the oesophagus, and serves as a 'tonsillar crypt'. Stratified squamous epithelium is infiltrated by lymphoid cells, i.e. T cells, plasma cells, macrophages, and dendritic cells, but not B cells, to form lymphoepithelium (LE). In the LE vimentin-, MHC II- and ATPase-positive cells possibly represent Langerhans' cells, but the appearance of 74.3 positive cells in the LE is unusual, because the 74.3 monoclonal antibody (mAb) recognises chicken follicular dendritic cells in the germinal centre and medulla of the bursal follicles. The subepithelial lymphoid tissue is organised into T- and B-dependent regions, which are the interfollicular areas and the germinal centres, respectively. Existence of high-endothelial venules in the interfollicular region suggests an extensive cellular connection between the oesophageal tonsil and the other lymphoid organs. In the resting oesophagus the lumen is closed, but during swallowing a bolus the crypt opens and the lymphoepithelium can be exposed to undigested food, antigens, infectious agents and vaccines. The location of the oesophageal tonsil, cranial to the stomach, may provide this organ with a unique role as compared to the other parts of the MALT; namely, it may contribute to the replication of infectious bursal disease virus (IBDV) and/or the pathogenesis of infectious bursal disease.

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Facing contrasting light regimes during a vegetation season and depending on canopy position, physiological plasticity of leaves is vital for tree species to sustain the optimal ratio between the benefit of carbon assimilation and the costs of photoprotection in a given leaf. We tested the seasonal adjustment of sun and shade leaf photochemistry of sessile oak (Quercus petraea (Matt.) Liebl.) to changing light environments by parallel investigation of the meteorological conditions, photosynthetic pigment content, PSII quantum efficiency and excitation energy quenching. Sun and shade leaves got adapted to their prevailing light regimes till mid of May. High LMA was a favourable trait in avoiding water loss and decreasing photoinhibition in both flushing and sun leaves, while low LMA optimized the light absorbing leaf surface in the lower canopy layer. Partitioning of excitation energy dissipation pathyways that is PSII photochemistry-Y(II), regulated-Y(NPQ) and non-regulated-Y(NO) quenching changed significantly during leaf ontogeny and with the position of leaves in the canopy. At 800 μmol m−2 s−1Y(II) < Y (NO) < Y (NPQ) was characteristic to early developmental stage of leaves from both canopy layers and to mature shade leaves, and Y(NO) < Y (II) < Y (NPQ) to mature sun leaves but the magnitude of Y(NPQ) and violaxanthin cycle activity differed in different canopy positions.

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In this study sap flow dynamics of mature sessile oak trees (Quercus petraea) in a marginal sessile oakturkey oak forest was investigated in 2009. That year spring was dry without significant rain in April and May and the driest month was August. Due to the extreme weather conditions the volumetric soil water content (SWC) of upper 30 cm was low on experimental days in May (0.13–0.14 cm3 cm−3) but it reached the lowest value in August (0.08 cm3 cm−3). Sap flow was measured in a dominant and a co-dominant tree by heat dissipation method from 26 March till 30 October. In the present paper several three-day long periods of the continuous seasonal recordings were chosen to represent the effects of typical weather conditions and different stages of canopy development on sap flow dynamics. The daily maximum sap flow density values of dominant and co-dominant trees were similar (0.30–0.32 cm3 cm−2 min−1) in moist period (July). Rains and transient increase of SWC after proceeding drought resulted in change of diurnal course of sap flow in experimental days of July. In this period dominant trees also showed considerable sap flow (0.19 cm3 cm−2 min−1) during night hours and short sap flow peaks in early morning (6:00 to 8:00 a.m.) indicating the refilling of desiccated tissues. After the progressive drought in August the daily maximum sap flow density decreased to 0.07 cm3 cm-2 min-1 in dominant tree and to 0.12 cm3 cm−2 min−1 in the co-dominant. Both trees exhibited gradual stomatal closure from morning hours.

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We examined the effects of different shift work schedules and chronic mild stress (CMS) on mood using animal model. The most common international shift work schedules in nursing were applied by three groups of Wistar-rats and a control group with normal light—dark cycle. One subgroup from each group was subjected to CMS. Levels of anxiety and emotional life were evaluated in light—dark box. Differences between the groups according to independent and dependent variables were examined with one- and two-way analysis of variance, with a significance level defined at p < 0.05. Interaction of lighting regimen and CMS was proved to be significant according to time spent in the light compartment and the average number of changes between the light and dark compartments. Results of our examination confirm that the changes of lighting conditions evocate anxiety more prominently than CMS. No significant differences were found between the results of the low rotating group and the control group, supposing that this schedule is the least harmful to health. Our results on the association between the use of lighting regimens and the level of CMS provide evidence that the fast rotating shift work schedule puts the heaviest load on the organism of animals.

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