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91.
The presence of phytoplasmas in seven coniferous plant species (Abies procera, Pinus banksiana, P. mugo, P. nigra, P. sylvestris, P. tabuliformis and Tsuga canadensis) was demonstrated using nested PCR with the primer pairs P1/P7 followed by R16F2n/R16R2. The phytoplasmas were detected in pine trees with witches’ broom symptoms growing in natural forest ecosystems and also in plants propagated from witches’ brooms. Identification of phytoplasmas was done using restriction fragment length polymorphism analysis (RFLP) of the 16S rDNA gene fragment with AluI, MseI and RsaI endonucleases. All samples showed RFLP patterns similar to the theoretical pattern of ‘Candidatus Phytoplasma pini’, based on the sequence of the reference isolate Pin127S. Nested PCR‐amplified products, obtained with primers R16F2n/R16R2, were sequenced. Comparison of the 16S rDNAs obtained revealed high (99·8–100%) nucleotide sequence identity between the phytoplasma isolates. The isolates were also closely related to four other phytoplasma isolates found in pine trees previously. Based on the results of RFLP and sequence analyses, the phytoplasma isolates tested were classified as members of the ‘Candidatus Phytoplasma pini’, group 16SrXXI. 相似文献
92.
Agriculture as a source of phosphorus causing eutrophication in Central and Eastern Europe 总被引:5,自引:0,他引:5
93.
Martyna A. Rzętała 《Journal of Soils and Sediments》2016,16(10):2458-2470
Purpose
Cadmium (Cd) is considered a toxic element and its concentrations are relevant to human health and the environment. Therefore, the purpose of the study was to determine the extent to which the bottom sediments of water bodies (artificial lakes and ponds) in the Silesian Upland in southern Poland are contaminated with Cd; an attempt was also made to determine the factors that condition spatial differences in the concentration of this element between individual water bodies in the region.Materials and methods
Measurements of the Cd content in bottom sediments were carried out in 35 water bodies in southern Poland in 2011 and 2012. Depending on the surface area and morphometric characteristics, from two to nine samples representative in terms of sediment thickness were collected in each water body. Cadmium concentrations were determined for 92 0.25 g aliquots using the TD-ICP method.Results and discussion
Cadmium content in all samples (0.7–580.0 mg kg?1) was higher than the natural range of concentrations for this element in the Earth’s crust (0.1–0.3 mg kg?1) and the geochemical background for Poland (0.5 mg kg?1) and, with a few exceptions, was also higher than the preindustrial concentration (1.0 mg kg?1) and the regional geochemical background (2.5 mg kg?1). Adopting natural Cd concentrations in the Earth’s crust (0.1–0.3 mg kg?1) as the baseline for the geoaccumulation index (Igeo), the sediments examined can be classified as extremely and heavily contaminated (and moderately contaminated in a small number of cases). The assessment of sediment quality based on Igeo, with the regional geochemical background (2.5 mg kg?1) adopted as the baseline, results in non-contaminated and moderately contaminated sediments being dominant with a far smaller number of heavily and extremely contaminated ones.Conclusions
In the case of several water bodies, Cd concentrations were at record levels that have not been found anywhere else in the world. On the basis of the Igeo, sediments of varying quality were found—from virtually uncontaminated to extremely contaminated. The Igeo index as an indicator of the quality of bottom sediments is a measure that requires careful interpretation, especially when different concentration levels regarded as natural are used for determining its value.94.
Forms of cadmium occurrence in the bottom sediment of a heated water reservoir, polluted substantially with this metal was analysed in the paper. Apart from the analysis mentioned above, a total cadmium content in the bottom sediment and a content of cadmium dissolved in the water of the reservoir was also determined. Dependences between particular forms of cadmium occurrence and its total content in the bottom sediment were analysed. An influence of cadmium content in water on the level of particular cadmium forms in the bottom sediment and an influence of other parameters of the reservoir's water on the content of cadmium in the bottom sediment were also examined. 相似文献
95.
Elmi Lotze Robert Wilsdorf Sandy Turketti Wojciech Józef Przybyłowicz Jolanta Mesjasz-Przybyłowicz 《Journal of plant nutrition》2015,38(10):1469-1477
Distribution of calcium in the apple has been quantified using mineral analyses of fruit sections during the mid-1900s by various researchers. Most of the work was done either at harvest, or after storage. We used Proton-induced X-ray spectrometry (PIXE) and Scanning Electron Microscopy to correlate Ca distribution in apples to results obtained from mineral analyses (MA). For fruit at harvest transverse distribution of Ca in ‘Braeburn’ apples determined by PIXE confirmed similar analyses with MA. It was not possible to establish a significant relationship between the total Ca concentration determined by PIXE and soluble Ca concentration from MA in this paper, either at harvest, or 80 days after full bloom (dafb). A significant correlation was found between PIXE and SEM results 80 dafb. 相似文献
96.
A comparison of the genetic structure for a group of 10 to 15 year old Scots pine trees originating from natural regeneration in an extremely polluted area with the genetic structure of 9 reference populations from the same geographical region but only slightly polluted, have demonstrated differences in alleles and genotypes frequencies. The observed heterozygosity (Ho) was lower by 12% for the group of trees from the polluted area. Fixation index (F) exhibited significant excess of homozygotes (F=0.15) in the group of tolerant trees. Average numbers of alleles per locus was higher by 8% in the group of trees from the polluted site. This differs from results from areas with the novel forest decline. Based on the differences in allele and genotype frequencies one might concluded that some of the alleles have a selective disadvantage or a selective advantage in the group of trees in the studied polluted area. 相似文献
97.
Dams I Bialoniska A Ciunik Z Wawrzenczyk C 《Journal of agricultural and food chemistry》2004,52(6):1630-1634
Starting from (R)-(+)- and (S)-(-)-pulegone, enantiomeric pairs of esters and lactones with the p-menthane system were obtained. The Claisen rearrangement of allylic alcohols and iodolactonization of gamma,delta-unsaturated acids were the key steps of syntheses presented. The structures of compounds were determined by both spectroscopic and crystallographic methods. Some of the synthesized compounds are characterized by interesting odoriferous properties. 相似文献
98.
Urbano G Aranda P Gómez-Villalva E Frejnagel S Porres JM Frías J Vidal-Valverde C López-Jurado M 《Journal of agricultural and food chemistry》2003,51(8):2415-2420
The effect of mild hydrothermal treatment and the addition of phytase under optimal conditions (pH 5.5, 37 degrees C) on the nutritive utilization of the protein of pea (Pisum sativum L.) flour was studied in growing rats by examining the chemical and biological balance. Mild hydrothermal treatment produced reductions of 83, 78, and 72%, respectively, in the levels of alpha-galactosides, phytic acid, and trypsin inhibitors and also produced a significant increase in the digestive utilization of protein. The additional fall in the levels of phytic acid caused by the addition of phytase did not lead to a subsequent improvement in the digestive utilization of protein. The mild hydrothermal treatment of pea flour produced a significant increase in the metabolic utilization of protein and carbohydrates, which was reflected in the protein efficiency ratio and food transformation growth indices. These effects were not observed in the phytase-supplemented pea diet. 相似文献
99.
Bożena Dębska Jacek Długosz Anna Piotrowska-Długosz Magdalena Banach-Szott 《Journal of Soils and Sediments》2016,16(10):2335-2343
Purpose
The application of bio-fertilizers is one of the management practices that can help to maintain or increase the content of organic matter (OM) and improve soil fertility in arable soils. While some results have been obtained in relation to the influence of bio-fertilizers on organic matter content, less in known about the fractional composition of humus.Materials and methods
The aim of this study was to determine the effects of the bio-fertilizer UGmax on soil total organic carbon (TOC), dissolved organic carbon (DOC), and the fractional composition of organic matter (C of humic acids (CHAs), C of fulvic acids (CFAs), and C in humins) in the humus horizon of an arable field. Measurements were taken in 2005 before the application of UGmax and in 2008, 3 years after its application, which was done in 2005, 2006, and 2007. Forty soil samples were taken in 2005 (the control year without UGmax), while 20 samples were taken after UGmax treatment and 20 from the control in 2008. Samples were always collected after the plants were harvested.Results and discussion
After the 3-year period of the experiment, the TOC content was 6.3 % higher in plots on which UGmax was applied in comparison to the control, while the DOC content was 0.19 percentage points lower after 3 years of bio-fertilizer use as compared to the initial year of the experiment. The contribution of DOC to TOC decreased significantly after the application of UGmax in comparison with the control. The content of CFAs and its contribution in the TOC pools in soil without UGmax was higher at the end of the experiment compared to the beginning, while there was an inverse relationship in the soil with the bio-fertilizer. In comparison with the control, organic matter in the soil treated with UGmax had a higher content of C of humic acids, C in humins, and higher CHAs/CFAs ratio.Conclusions
We conclude that the use of a bio-fertilizer that increases the stable fractions of organic matter provides evidence of an increase in the soil OM stability. In turn, the contribution of the organic matter fractions that are more resistant to decomposition is crucial for increasing soil carbon sequestration.100.
Stanisław Małek 《Water, air, and soil pollution》1996,88(1-2):93-107
The purpose of the present experiment was to describe the influence of various mineral fertilizers on the development of Larix decidua Mill. seedlings subject to the influence of simulated acid rain of pH 2.5, 3.0, 3.5, 4.0, 4.5. The seedlings were fertilized every month (from April up to October), in order to counteract acid rain. The composition of the fertilizers was diversified in order to select an optimum variant. Fertilizer with NK applied to the needles (Florovit) and NPK applied to the soil (Fruktus 2) as well as dolomite lime applied to the soil. One row per set was left without fertilization as a control for each pH step of acid rain treatment. The analysis of biometric characteristics showed that a two-year period of investigations was too short to estimate effects on Larix decidua Mill. seedlings. It, however, indicated important trends. High correlations were found between particular growth parameters i.e. diameter of root neck, root mass, total mass of: seedlings, needles, main shoots, lateral shoots, ligneous parts, total overground parts. No strong correlations were observed between the above mentioned parameters and the total height of the seedlings. Among the different treatments the best development was achieved at pH 4.0, whereas the weakest development was observed at pH 2.5. The analysis showed a decrease in biometrical features along with an increase in acidity of acid rain solution. The first year of the experiment had the greatest influence upon the growth of Larix decidua Mill. seedlings. Significant improvement in growth, in relation to control plots, was achieved by using NK-fertilizers onto needles — the best results, and NPK onto soil. The best increment of the height of seedling was noticed at pH 3.5. In the second year of the experiment the effects of pH of acid rain and fertilization decreased — no significant effect on biometrical features was observed. Applaying NPK fertilizer onto soil showed a positive effect in relation to dolomite treatment. The best increment was noticed at pH 4.0. 相似文献