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41.
With regard to the low cation-exchange capacity and large saturated hydraulic conductivity of sandy soils, a field experiment was carried out in 2006–2007 to determine the impact of zeolite on nitrogen leaching and canola production. Four nitrogen (N) rates (0, 90, 180, and 270 kg ha–1) and three zeolite amounts (3, 6 and 9 t ha?1) were included as treatments. The results demonstrated that the highest growth parameters and seed yield were attained with 270 kg N ha?1 and 9 t zeolite ha?1. However, the highest and the lowest seed protein percentage and oil content were obtained with 270 kg N ha?1 accompanied by 9 t zeolite ha?1, respectively. Nitrate concentration in drained water was affected by nitrogen and zeolite. The lowest and highest leached nitrate values were found in control without N and zeolite (N0Z0) and in treatments with the highest N supply without zeolite (N270Z0), respectively. In general, nitrogen-use efficiency decreased with an increase in N supply. Application of 9 t zeolite ha?1 showed higher nitrogen use efficiency than other zeolite amounts. Also, application of more N fertilizer in soil reduced nitrogen uptake efficiency. In total, application of 270 kg N ha?1 and 9 t zeolite ha?1 could be suggested as superior treatment.  相似文献   
42.
The high radioactivity and trace elements in drinking water are common concerns for human health. The aim of this study was to investigate the eligibility of groundwater for drinking purpose in terms of both radioactivity and trace element contents in Eskisehir Region (Turkey). The study area is located in a highly populated residential area where water supply is mostly met from groundwater. The area is about 20,000 km2, where igneous, metamorphic, and sedimentary rocks are exposed. The 209 water samples collected from 84 water resources (including thermal waters) were analyzed with respect to major ions, trace elements, and radioactivity (gross alpha and gross beta) during both in wet and dry seasons. Based on the analysis results, trace elements in 49 samples of 84 water resources were over the limits of Code TS 266 1997 (Turkish Drinking Water Standards) and WHO 1993 standards. Particularly, Fe, Mn, Al, As, Ba, Zn, Cr, Cu, and B ion concentrations exceeded the limits. The gross alpha values in 18 locations and gross beta values in three locations also exceeded the limits of aforementioned standards in terms of radioactivity (gross alpha?=?0.1 Bq L?1; gross beta?=?1 Bq L?1). Furthermore, water radioactivity levels were close to the allowable limits in 33 water resources. The obtained results explicitly indicate that there is a strong relationship between the higher radioactivity–trace element contents and geochemical composition of rocks, which controls the radioactivity and trace element concentrations present in the aquifer.  相似文献   
43.
Plant peroxidases belong to a multigene family and posses highly conserved domains allowing to design oligonucleotide primers to amplify DNA sequences coding for peroxidases from plants with unsequenced genomes. Peroxidase gene-based polymorphism among Malus species, and correlation between peroxidase markers were deduced in this study. Turkish apple germplasm was evaluated using 14 peroxidase specific primers. Targeted-PCR amplification of genomic DNA from 192 apple genotypes available in the Turkish genetic resources yielded polymorphisms giving a similarity range from 0.56 to 0.98 with a mean of 0.77. Based on the POGP gene polymorphism, two distinct clusters were detected among the apple accessions, suggesting different evolutionary pathway. Correlation estimates as an indication of linkage disequilibrium between POGP markers ranged from −0.22 to 0.90, suggesting that few POGP markers were clustered and the remaining POGP markers evenly distributed throughout the apple genome. These results demonstrate that primers targeting the peroxidase gene family can be used to study genotypic diversity and evolutionary relationships on an intra- and inter-specific basis.  相似文献   
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45.
The chemical composition of essential oils isolated by hydrodistillation from the aerial parts of Achillea gypsicola Hub-Mor., Achillea biebersteinii Afan. and n-hexane extracts obtained from the flowers of A. gypsicola and A. biebersteinii Afan. was analyzed by GC and GC–MS. Camphor (40.17–23.56%, respectively), 1,8-cineole (22.01–38.09%, respectively), piperitone (11.29–0.37%, respectively), borneol (9.50–5.88%, respectively) and α-terpineol (1.56–5.15%, respectively) were found to be the main constituents in A. gypsicola and A. biebersteinii essential oils. Furthermore, hexane extracts of A. gypsicola and A. biebersteinii consist of mainly camphor (37.78–27.88%, respectively), 1,8-cineole (13.43–24.78%, respectively), piperitone (15.57%-tr, respectively), n-eicosane (1.61–9.68%, respectively), n-heneicosane (2.56–9.55%, respectively), n-tricosane (3.46–10.04%, respectively), linoleic acid (6.19–3.17%, respectively) and borneol (5.66–5.58%, respectively). Although the oils and extracts were characterized relatively by high content of oxygenated monoterpenes, hexane extracts of the plant samples relatively rich in n-alkanes, fatty acids and fatty acid esters as compared with the oil. The oils and hexane extracts were also tested against 12 phytopathogenic fungi and the oils found to be more toxic as compared with hexane extracts of the plant samples. A. gypsicola oil only did not inhibit the growth of Fusarium graminearum. The extracts also strongly increased the growth of Fusarium equiseti and F. graminearum. Therefore, the antifungal activity of the oils can be attributed to their relatively high content of oxygenated monoterpenes. The results of herbicidal assays of the essential oils and hexane extracts of the plant samples against five important weeds in cultivated areas, Amaranthus retroflexus L., Chenopodium album L., Cirsium arvense L. (Scop.), Lactuca serriola L. and Rumex crispus L. showed that, in particular, the oils had inhibitory effects on the seed germination and seedling growth of A. retroflexus, C. arvense and L. serriola. The hexane extracts also showed lower herbicidal effect against the weeds in comparison to that of the oils. The findings of the present study suggest that the essential oils have a potential to be used as herbicide as well as fungicide.  相似文献   
46.
Many stress-related interactions such as pathogen infection, insect tolerance, salt tolerance, auxin degradation, cell wall lignification, tissue suberization, and plant senescence involve various isoforms of peroxidases. Peroxidase gene polymorphism (POGP) markers have been used to estimate diversity, relationships and population structure among 80 Citrus and their relatives in Aurantioideae by using unweighted pair group method arithmetic average (UPGMA) and bayesian substructuring analysis. Fourteen primers produced a total of 148 fragments and 147 of them were polymorphic. The UPGMA analysis demonstrated that the accessions had a similarity range from 0.27 to 0.98 and were distinguished. The results of this study were mostly consistent with previous reports of different marker systems, but few different findings were also detected. The subtribe Clauseninae (tribe Clauseneae) did not clearly separate from the subtribes of the tribe Citreae. Substructuring analysis indicated that there were six subpopulations among the accessions studied. This study revealed that the POGP markers can be utilized to estimate genetic diversity, relationships and population structure in Citrus and related species in the Aurantioideae subfamily.  相似文献   
47.
The purpose of this study was to determine Bartonella henselae prevalance in cats in Ankara. Whole bloods and sera collected from 256 cats were investigated for the presence feline Bartonella species by culture and sera were tested for the presence of antibodies against B. henselae IgG using immunofluorescence assay. Bartonella species were isolated by blood culture from 24 (9.4%) cats. Bartonella isolates were subjected to restriction fragment length polymorphism (RFLP) by using TaqI and HhaI endonucleases to identify species. Twenty-one isolates were determined as B. henselae and three of 24 isolates were determined as Bartonella clarridgeiae with RFLP. The bacteraemia prevalence and seroprevalence of B. henselae IgG antibodies in cats was detected as 8.2% and 18.6% respectively. This is the first report on B. henselea and B. clarridgeiae in cats in Turkey.  相似文献   
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49.
Deltamethrin and thiachloprid are an α-cyano class pyrethroid and neonicotinoid insecticide, respectively. Recently, a pesticide combining deltamethrin and thiacloprid has also been released. In the present study, the acute and subacute toxic effects of deltamethrin, thiachlopride, and a combination of these insecticides, on the lymphoid organs (spleen, thymus and bone marrow), polymorphonuclear leukocytes (PMNs) and plasma of rats, were determined to better understand mammalian antioxidant-oxidant and inflammatory system responses. For this purpose, rats were treated orally with different doses of thiacloprid (single acute dose of 112.5 mg/kg); subacute dose of 22.5 mg/kg/day for 30 days; deltamethrin (single acute dose of 15 mg/kg); subacute dose (3 mg/kg/day for 30 days), or a combination of these pesticides. Results were compared with those from a comparable dosing regimen with the known immunosuppressive drug cyclophosphamide. Pesticide treatments caused significant changes in the levels of liver and kidney injury markers. Antioxidant enzyme (catalase and glutathione peroxidase), glutathione and plasma antioxidant levels decreased but lipid peroxidation increased in all lymphoid organs and the plasma. Glutathione-S-transferase and especially DT-diaphorase activity, decreased after thiacloprid treatment. Myeloperoxidase activity, carbonyl content, lipid peroxidation and total nitrite levels increased in PMNs and plasma. When evaluated as a whole, the oxidative and inflammatory stresses seen in the pesticide combination groups were not much more pronounced than in the groups treated with a single pesticide. In terms of the evaluated biochemical parameters, the pesticides showed similar effects to cyclophosphamide.  相似文献   
50.
A major objective in the remote sensing of convective storms by radar is the clear and reliable differentiation between regions of hail and regions of rainfall. This report describes the application of the differential reflectivity (Z(DR)) radar technique to the problem of hail detection. The procedure is based on the markedly different polarization-dependent backscatter characteristics of rain and hail. Field experiments conducted in Colorado during the spring of 1983 provide significant evidence of hail detection with this new radar technique.  相似文献   
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