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111.
Mehmet Erhan Göre 《Phytoparasitica》2009,37(1):87-94
A collection of 30 strains of Verticillium dahliae, recovered during 2004–2006 from 12 cultivars of chrysanthemum (Chrysanthemum morifolium) in five districts of İzmir province in Turkey, was assigned to vegetative compatibility groups (VCGs) based on pairings
of complementary nitrate-nonutilizing (nit) mutants induced on a chlorate-containing medium. Of these strains, nine were assigned to VCG1, seven to VCG2A, 11 toVCG2B
and one to VCG4B. The remaining two strains could not be tested for vegetative compatibility because of their inability to
yield nit mutants. Pathogenicity tests conducted by the root-dip method, demonstrated that wilt of chrysanthemum in Turkey is caused
by V. dahliae, and most strains in VCG1 were significantly more aggressive to chrysanthemum than those in VCGs 2 and 4B. This is the first
known study in the world of the VCGs of V. dahliae isolates from chrysanthemum. 相似文献
112.
Triploidy in fertilized eggs of Melicertus kerathurus was induced by cold (8, 10, 12°C) and heat (34, 36, 38°C) shock for different duration times (2, 4 and 8 min) after 10 min of post spawning. The best individual treatment produced 64.5% triploid nauplii in cold shock application at a temperature of 10°C for a duration of 8 min. Temperature did not have significant effect (P > 0.05) on triploid rate but duration time had a significant effect (P < 0.05) for individual cold or heat shock. This study demonstrates that because of a wide variety of effective parameters, it is essential to optimize shock conditions for each species strain at each location. 相似文献
113.
Acute toxicity of ammonia in Meagre (Argyrosomus regius Asso, 1801) at different temperatures 下载免费PDF全文
Argyrosomus regius (3.0 ± 0.9 g) were exposed to different concentrations of ammonia in a series of acute toxicity tests by the static renewal method at three temperature levels (18, 22 and 26°C) at a pH of 8.2. Low temperature clearly increased the tolerance of the fish to total ammonia nitrogen (TAN) and unionized ammonia (NH3) (P < 0.05). While the 96‐h LC50 values of TAN were 19.79, 10.39 and 5.06 mg L?1, the 96‐h LC50 of NH3 were 1.00, 0.70 and 0.44 mg L?1 at 18, 22 and 26°C respectively. The safe levels of NH3 for A. regius was estimated to be 0.10, 0.07 and 0.04 mg L?1 at 18, 22 and 26°C respectively (P < 0.05). This study clearly indicates that A. regius is more sensitive to ammonia than other marine fish species cultured on the Mediterranean and Eastern Atlantic coasts. 相似文献
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115.
Coelhan M Bromig KH Glas K Roberts AL 《Journal of agricultural and food chemistry》2006,54(16):5731-5735
A method was developed for the determination of the biocide ortho-phenylphenol (biphenyl-2-ol; OPP) in beer, using deuterated OPP as an internal standard. A new liquid-liquid extraction procedure, employing acetonitrile, diethyl ether, and n-pentane, afforded rapid phase separation. The evaporated extract was derivatized with pentafluorobenzyl bromide in a water-acetonitrile mixture that was buffered with potassium carbonate, followed by extraction of the derivative into cyclohexane and analysis by gas chromatography-mass spectrometry in electron ionization mode. The method enables the detection of OPP in 50 mL of beer at concentrations as low as 0.1 microg/L and provides a linear range of quantification of 0.5-40 microg/L. Samples from 61 beers canned over the past 12 years and sold in 27 countries were analyzed for OPP. In 40 of them, the target compound was present at concentrations of 1.2-40 microg/L. Our investigations indicate that the ends of the cans, which contain sealing material presumably treated with OPP, are responsible for this contamination. 相似文献
116.
Matrix metalloproteinases (MMPs) have been implicated in the pathogenesis of several central nervous system (CNS) diseases. In this study, we investigated the presence of Listeria monocytogenes antigens and detected the expression of MMP-9 and MMP-7 in the brains of 22 sheep with clinical signs and histopathological findings characteristic of listerial meningoencephalitis. Archived sections from the brainstem, cerebrum, and cerebellum were stained for immunohistochemistry. L. monocytogenes antigens were located mainly in the cytoplasm of neutrophils and some macrophages and/or extracellularly within microabscesses of the brainstem. MMP-9 was mainly immunolocalised in the endothelial cells, microglial cells, and neurons especially in inflammatory areas. MMP-7 immunoreactivity was detected in perivascular cuffs, microglial cells, and only a few neurons. Overall, immunohistochemistry in formalin-fixed, paraffin-embedded tissues is a useful tool for the diagnosis of encephalitic listeriosis caused by L. monocytogenes, and MMP-9 and MMP-7 may contribute to the pathogenesis of listerial meningoencephalitis. 相似文献
117.
Mehmet Burak Taşkın Özge Şahin Havva Taskin Orhan Atakol Ali Inal 《Journal of plant nutrition》2018,41(9):1148-1154
Phosphorus (P) is one of the least available mineral nutrients to the plants in calcareous and alkaline soils. In this study, we investigated the synthesis, characterization and use of synthetic nano-hydroxyapatite (NHA), P uptake by plants as well as its residual effects. Soluble P source (H3PO4) was also included as treatment for comparison. NHA prepared by wet chemical techniques, characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and elemental dispersive X-ray (EDX) analysis. NHA and H3PO4 were applied at a rate of 200 mg kg?1 to find out their effects on phosphorus nutrition and growth of lettuce on the low and high calcareous soil. In addition to this, residual effects of NHA and H3PO4 were also determined for lettuce plants grown after first lettuce plants in the both soil. Dry weights of the first and second lettuce plants grown in low and high calcareous soil were significantly increased by applied phosphorus regardless of the source. NHA seems to be more effective than that of ordinary phosphorus source (H3PO4-P) on growth and P concentration of the lettuce plants. The promising results of this study needs to be supported with long term field studies regarding the uptake, translocation and interactions of nano-P with the other elements. 相似文献
118.
119.
Mehmet Tekin Duygu Sari Mursel Catal Cengiz Ikten Petr Smykal R. Varma Penmetsa Eric J. Von Wettberg Cengiz Toker 《Genetic Resources and Crop Evolution》2018,65(1):67-77
Wild Cicer species are considered as useful genetic resources for resistance to biotic and abiotic stresses due to limited resistance in cultivated chickpeas. As a wild perennial species in the genus Cicer L., Cicer isauricum P.H. Davis is an endemic species to Turkey and endangered status according to the International Union for Conservation of Nature criteria. Here we report on its eco-geographic distribution and environmental stresses that affect the species, and advocate for its in situ and ex situ conservation. A new population of the species was discovered in Geyikbay?r?, Güllük Mountains in Antalya, Turkey. Cicer isauricum not only suffers from significant biotic stresses such as ascochyta blight [Ascochyta rabiei (Pass.) Labr.], pod borer (Helicoverpa armigera Hübner) and broomrape (Orobanche sp.), but is also subjected to drought and heat stress in its habitat. Infection with ascochyta blight in natural habitats was diagnosed by molecular techniques, and pod borer and broomrape were observed only phenotypically. PCR amplification of the internal transcribed spacer region of genomic DNA from cultured fungal isolates, yielded sequences with 100% nucleotide identity with the corresponding sequence in GeneBank for Didymella rabiei Kovachevski (anamorph: A. rabiei). The pathogen may have co-evolved with C. isauricum in the newly discovered site. Because C. isauricum is exposed to drought and accompanying heat stress in its natural habitat, it appears able to tolerate heat stress up to 45 °C during podding stage and terminal drought in late summer from its woody, deep rooting. C. isauricum bears multiple flowers per axil, a potentially useful trait in cultivated chickpea. In conclusion, C. isauricum is a potential genetic source for resistance to biotic and abiotic stresses, in need of greater protection due to its endangered status. 相似文献
120.