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51.
Damage caused by the wheat pathogen Mycosphaerella graminicola increased rapidly during the last two decades in the Czech Republic. We collected isolates from naturally infected fields in seven wheat-growing locations and analysed these using eight microsatellite markers. All markers were highly polymorphic. We found a high degree of genetic diversity and low clonality within all sampled Czech populations. We identified 158 unique multilocus haplotypes among 184 isolates. Field populations showed weak genetic structure but we detected more differentiation between climatic regions within the Czech Republic. We compared the Czech field populations to populations from the United Kingdom, Germany and Switzerland and found a marked differentiation between Czech populations and Western European populations. We hypothesize that decades of different agricultural practices, including the use of different wheat cultivars, may explain this genetic differentiation. We detected a rapid increase in QoI fungicide resistance during the sampling period from 2005 to 2011, coinciding with the widespread application of this class of fungicides in the Czech Republic. M. graminicola populations in the Czech Republic underwent a rapid adaptive evolution from sensitivity to resistance similar to what was described earlier in Western Europe.  相似文献   
52.
53.
With the development of the textile industry, there has been a demand for dye removal from contaminated effluents. In recent years, attention has been directed toward various natural solid materials that are capable of removing pollutants from contaminated water at low cost. One such material is sugarcane bagasse. The aim of the present study was to evaluate adsorption of the dye Acid Violet Alizarin N with different concentrations of sugarcane bagasse and granulometry in agitated systems at different pH. The most promising data (achieved with pH 2.5) was analyzed with both Freundlich and Langmuir isotherms equations. The model that better fits dye adsorption interaction into sugarcane bagasse is Freundlich equation, and thus the multilayer model. Moreover, a smaller bagasse granulometry led to greater dye adsorption. The best treatment was achieved with a granulometry value lower than 0.21 mm at pH 2.50, in which the total removal was estimated at a concentration of 16.25 mg mL−1. Hence, sugarcane bagasse proves to be very attractive for dye removal from textile effluents.  相似文献   
54.

Background

The aim of the present study was to investigate biochemical and oxidative stress responses to experimental F. tularensis infection in European brown hares, an important source of human tularemia infections.

Methods

For these purposes we compared the development of an array of biochemical parameters measured in blood plasma using standard procedures of dry chemistry as well as electrochemical devices following a subcutaneous infection with a wild Francisella tularensis subsp. holarctica strain (a single dose of 2.6 × 109 CFU pro toto).

Results

Subcutaneous inoculation of a single dose with 2.6 × 109 colony forming units of a wild F. tularensis strain pro toto resulted in the death of two out of five hares. Plasma chemistry profiles were examined on days 2 to 35 post-infection. When compared to controls, the total protein, urea, lactate dehydrogenase, aspartate aminotransferase and alanine aminotransferase were increased, while albumin, glucose and amylase were decreased. Both uric and ascorbic acids and glutathione dropped on day 2 and then increased significantly on days 6 to 12 and 6 to 14 post-inoculation, respectively. There was a two-fold increase in lipid peroxidation on days 4 to 8 post-inoculation.

Conclusions

Contrary to all expectations, the present study demonstrates that the European brown hare shows relatively low susceptibility to tularemia. Therefore, the circumstances of tularemia in hares under natural conditions should be further studied.  相似文献   
55.
Proso millet belongs to the oldest cereals that human is using. Eight varieties of proso millet were cultivated in Ceske Budejovice from1998 to 2000 and Cerveny Dvur from 1999 to 2000. The crude protein content was determined according to Kjehladl method and amino acid content was determined chromatographically after acid and oxidative acid hydrolysis. Although the protein content of proso (11.6% of dry matter) was similar to wheat, the grain of proso was significant richer in essential amino acids (leucine, isoleucine, methionine) then wheat. Hence, the protein quality of proso (Essential Amino Acid Index) was higher (51%) compared to wheat. The proso grain contained about 3.3 g kg−1 of the limiting amino acid-lysine. Significant differences in protein and its quality were found among the evaluated proso varieties. The varieties Toldanskoe and Lipetskoe were the most different from the others in protein and amino acid content and Amino Acid Score of individual acids. They had the lowest content and quality of protein. The seed coat of these varieties was red. The amino acid and protein content was significantly influenced by weather during the year. Dry conditions caused an increase of protein but its quality was decreased.  相似文献   
56.
From the year 2000 on, different steps have been taken to study the real extent of pesticide use in Germany. For this paper, the data of farms in North East Germany were examined for the chemical plant protection measures carried out between 2000 and 2004. Results are presented for 97 winter wheat fields and 68 fields of oil seed rape. Pesticide use intensity is described as frequency of use, number of pesticides used, and treatment frequency index. Number and composition of tank mixtures are given in detail. More over it can be shown that the use of reduced dosages contributes to smaller overall pesticide use intensity.  相似文献   
57.
The aim of the study was to evaluate the effect of subchronic exposure to the herbicide LASSO MTX (alachlor 42% W/V) on biometric parameters and important liver biomarkers in the common carp (Cyprinus carpio). One year old fish were exposed for 28 days to LASSO MTX added to the tank water at concentrations of 240 and 2400 μg L−1. The exposure did not affect fish biometric parameters. Glutathione-S-tranferase (GST) activity in liver (hepatopancreas) remained unchanged in exposed fish when compared to controls. However, significant induction of total cytochrome P 450 (CYP 450), ethoxyresorufin-O-deethylase (EROD) activity and elevated glutathione (GSH) in liver of exposed fish were detected.  相似文献   
58.
The aim of the study was to confirm the presence of rutin, one of the most common quercetin glycosides, and other quercetin derivatives in plants of genus Amaranthus, to investigate the influence of the species and variety on rutin distribution in the plant and content changes during growing season. The rutin content was determined by micellar electrokinetic capillary chromatography in individual plant parts at the beginning of the growth, at the flowering stage and at the maturity stage of five Amaranthus species. The total quercetin content was determined by micellar electrokinetic capillary chromatography too. The rutin content in amaranth ranged from 0.08 (in seeds) to 24.5 g/kg dry matter (in leaves). Comparison of the determined total quercetin content and the calculated content of quercetin released from rutin did not prove important presence of quercetin or other quercetin derivatives than rutin. Only amaranth leaves sampled at the maturity stage probably contained quercetin or quercetin derivatives. Significant differences in the rutin content were established among species and as well varieties. Amaranthus hybrid and A. cruentus were the best sources of rutin.  相似文献   
59.
Residues of the insect growth regulator diflubenzuron were quantified on horse chestnut (Aesculus hippocastanum L.) leaves treated with a diflubenzuron 480 g litre?1 SC, Dimilin. To analyse the samples, an analytical procedure was developed involving a simple extraction step followed by high‐performance liquid chromatography on an octadecyl‐modified silica column with methanol + 0.01 M ammonium acetate mobile phase. The results showed diflubenzuron to be highly stable on horse chestnut leaves; more than 4 months (127 days) after application, 38% (on average) of the insecticide still remained on/in the leaves. The data confirmed biological observations showing diflubenzuron's long‐term efficacy against the horse chestnut leafminer, Cameraria ohridella Deschka & Dimi?, which is the most important pest of the horse chestnut in Europe. The hypothesis of possible penetration of diflubenzuron into the leaf mass is explored and discussed. Copyright © 2006 Society of Chemical Industry  相似文献   
60.
The secondary osmoregulatory canals in the scolex and neck region of Silurotaenia siluri, a parasite of the catfish Silurus glanis (L.), terminate below the tegument basal plasma membrane. The basal plasma membrane of the osmoregulatory canal syncytium is in tight contact with the tegument basal plasma membrane.  相似文献   
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