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71.
72.
Summary The new Botanical Garden of the Polish Academy of Sciences was established in 1974 as an institution dedicated to collecting, conserving, and evaluating crop genetic resources and their wild progenitors. The main object of this research is rye (Secale L. spp.) — the cereal of great importance to Poland. The genetic resources of rye are preserved in living field collections, as well as in a seed stock bank. The living collection contains 1.193 taxa, including 12 species ofSecale and 788 different rye cultivars. The seed bank stores 773 taxa of rye kept in glass containers (in vacuum, neutral gases or with silica gel) with optimum low moisture content in the seeds. Biochemical, physiological and genetical investigations are carried out for the estimation of safe and suitable conditions of seed dehydration and long term storage. These genetic resources of rye serve as material for taxonomic and phylogenetic studies, as well as for the evaluation of their selected breeding properties, especially seed protein content and its nutritional value. The taxonomic studies are performed using the isoenzyme technique and numerical methods. The enzymatic variation within the rye species, cultivars and inbred lines, are analysed. For the protein resources evaluation, different techniques are applied: the histochemical staining of seed slices. scanning electron microscope observations, and the chemical analyses of the entire amino acid composition of seed proteins. These results are used to select the most valuable taxa, which are then proposed to be used in the rye breeding programme.
Beurteilung der genetischen Ressourcen des Roggens im Botanischen Garten der Polnischen Akademie der Wissenschaften in Warschau
Zusammenfassung Der neue Botanische Garten der Polnischen Akademie der Wissenschaften wurde 1974 als eine Institution gegründet, die sich der Sammlung, Erhaltung und Beurteilung der genetischen Ressourcen von Kulturpflanzen und deren Wildformen widmen soll. Hauptgegenstand dieser Untersuchung ist der Roggen (Secale L. spp.) — ein Getreide, das für Polen von großer Bedeutung ist. Die genetischen Ressourcen des Roggens werden sowohl in lebenden Sammlungen auf dem Felde als auch in einer Samenbank erhalten. Die lebende Sammlung enthält 1193 Taxa (12 Roggen-Arten und 788 Roggen-Sorten). Die Samenbank umfaßt 773 Roggen-Taxa in Glasbehältern (im Vakuum, neutralen Gasen oder Silikagel) mit optimal niedrigem Samenfeuchtigkeitsgehalt. Biochemische, physiologische und genetische Untersuchungen werden durchgeführt zur Ermittlung sicherer und passender Bedingungen der Samenentwässerung und Langzeitlagerung. Diese genetischen Ressourcen des Roggens dienen als Material für taxonomische und phylogenetische Studien sowie für die Beurteilung ihrer züchterischen Eigenschaften, besonders Eiweißgehalt der Samen und sein Nährwert. Bei den taxonomischen Studien werden die Isoenzym-Technik und numerische Methoden angewendet. Die enzymatische Variation innerhalb der Roggen-Arten, -Sorten und -Inzuchtlinien werden untersucht. Für die Beurteilung der Protein-Ressourcen werden verschiedene Techniken angewendet: histochemische Färbung von Samenschnitten, Beobachtungen mit dem Raster-Elektronenmikroskop und chemische Analysen der gesamten Aminosäure-Zusammensetzung der Samen-Proteine. Diese Ergebnisse werden benutzt, um die wertvollsten Taxa aufzufinden, die dann zur Anwendung in Roggen-Zuchtprogrammen vorgeschlagen werden.

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73.

Background Goal and Scope  

The application of solid-liquid extraction is proposed to assess extractable fractions of components in soil. The application of a several step scheme could give a lot of information about mobility of metals associated with specific solid phases, especially after separation of top and bottom layers of studied soil. In this study, it was aimed to take into solution metal fractions of major (Ca, Mg, Mn, Fe) and trace elements (Cr, Co, Cu, Zn, As, Cd, Pb) from soil collected in urban areas. The fractions were defined by using chemical extraction operationally. The extraction behavior of studied elements in a six-step sequential extraction procedure is discussed with respect to the properties of the reagents used.  相似文献   
74.
Phosphorus (P) sorption processes in soils contribute to important problems in agriculture: a deficiency of this plant nutrient and eutrophication in aquatic systems. Soil organic matter (SOM) plays a major role in sorption processes, but its influence on P sorption remains unclear and needs to be elucidated to improve the ability to effectively manage soil P. The aim of this research was to investigate the influence of SOM on P sorption. The study was conducted in sandy soil profiles and in topsoils before and after removal of SOM with H2O2. The results were interpreted with the Langmuir and Freundlich isotherms. Our results indicated that SOM affected P sorption in sandy soils, but that P sorption also depended on specific soil properties (e.g. values of the degree of P saturation (DPS), P sorption capacity (PSC) and pH) often related to land use. Removal of SOM decreased PSC in most of the topsoils tested; other soil properties became important in controlling P sorption. An increase in P desorption observed after SOM removal indicated that SOM was potentially that soil constituent which increased P binding and limited P leaching from these sandy soils.  相似文献   
75.
Genetic diversity and relationships of 11 species and cultivars belonging to different Angiosperms families were examined using sodium dodecyl sulfate seed protein markers. The protein was resolved into 36 bands (for soybean), 41 (for quinoa), 35 (for buckwheat), and 28 to 39 bands of Amaranth species, respectively. All species and cultivars can be distinguished from each other. Soybean, quinoa, and buckwheat species had a characteristic protein pattern showing a high degree of polymorphism. The protein patterns of soybean were considerably different from other species. Amaranth species had similar seed protein electrophoretic profile. The similarity coefficients calculated on the basis of presence and absence of bands ranged from 0.08 to 0.97. Following the UPGMA algorithm of similarity coefficients, the examined species and varieties could be clustered into two similarity groups. Our results did not confirm the Tachtadzjan hypothesis that Polygonales (e.g., buckwheat) and Caryophyllales (e.g., quinoa and amaranth) are closely related. Our data rather indicate occurrence of significant genetic distance (similarity coefficients 0.05-0.10). Also, it is doubtful that amaranth and quinoa species are also closely related (similarity coefficients varied from 0.16 to 0.25). It seems that soybean, quinoa, buckwheat, and amaranth (as a genus) can be considered as phylogenetic distant taxa. Differences and similarities in the secondary structure were observed by circular dichroism spectra. Some similarity was found between these plants in their soluble protein fractions and amino acid composition. These plants can be a substitution of each other as well as for cereals.  相似文献   
76.
Plant cover is an easily discernible, recognisable and labile component of the natural environment that reacts to changes in other components. One of the more important components controlling vegetation cover is the soil, and both vegetation and soil are influenced by topography, amongst other things. As it is in the humus-accumulation horizon of soils that vascular plants have most of their roots, these species are capable of reacting to qualitative and quantitative differences in its composition. The relationship between topography, soil and vegetation were assessed on the basis of three catenal sequences representative of Poland's Wigierski (Lake Wigry) National Park. The aim was to determine if changes in soil along the catenae were reflected in changes in plant community (species richness, species composition, and indicator species). We made use of soil analysis, phytosociological analysis of vegetational structure, and Ellenberg indicator values. Correlations between 23 variables allowed distinguishing 6 statistically-significant groups of variables with main ordinating groups being the percentage shares of species indicating relatively dry, slightly moist soils, the combined shares of these species, altitude above sea level and relative elevation. The first two axes of a Principal Components Analysis were strongly related to soil moisture and elevation (axis 1) and to soil fertility (axis 2). Together, these axes accounted for more than 60% of the variability. Within the forest communities, however, fertility was the most important factor. The three catenae differed most in terms of their species richness and least in soil characteristics. An intermediate place was taken by the weighted Ellenberg's indicator values. The lower sections of catenae were found to have more similarity in terms of soil, vegetation and their interrelationships and patterns than the upper parts.  相似文献   
77.
The aim of this experiment was to investigate whether the amount of Cu added to the diet of rats can be reduced without adversely affecting the antioxidant status of tissues and growth, and whether copper nanoparticles can be used for this purpose. For four weeks, four experimental groups of rats were fed diets with two dosages of added Cu (standard—6.5 or 3.25 mg/kg) in two forms (standard—CuCO3 or copper nanoparticles). Replacing the CuCO3 supplement with CuNPs resulted in a decreased lung weight and an increased Cu content in brain, kidney and lung, intensification of lipid peroxidation processes, and weakened antioxidant defence in the lungs and kidneys. This treatment also reduced the Cu content in heart, level of lipid oxidation in the liver and testes and improved antioxidant defence in the brain. Reducing the addition of Cu to the diet from 6.5 to 3.25 mg/kg reduced lung weight and increased lipid peroxidation in the liver, heart and lungs, and also weakened antioxidant defence in the lungs and testes. This treatment also weakened the lipid peroxidation process in the spleen, small intestine and brain and strengthened the antioxidant defence of the brain and kidneys. In conclusion, replacing CuCO3 with CuNPs and reducing the level of Cu in the diet of rats has a particularly unfavourable effect on the respiratory system, causing adverse changes in the lungs. However, these treatments have a clearly positive effect on the redox status of the liver and brain.  相似文献   
78.
Journal of Soils and Sediments - The aim of the study was the calculation of geochemical, ecological, and ecotoxicological indices for the assessment of risk resulting from the presence of trace...  相似文献   
79.
80.
This paper addresses the oxidation by ultraviolet radiation of methylparaben, a ubiquitous and suspicious preservative which is massively added to cosmetics and personal care products. Experiments included pH and temperature variation, as well as several experimental conditions such as presence/absence of hydrogen peroxide, titanium dioxide, or some different water matrix (surface water or ground water). Results were evaluated under the line source spherical emission model, so quantum yield was the adequate target variable for explaining the process. A modified Arrhenius correlation including pH level was used for modelling the whole system.  相似文献   
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