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1.
We investigated the effects of various qualities of light-emitting diode (LED) light sources on the growth and carbohydrate accumulation of grape rootstock ‘Teleki 5BB’ culturedin vitro. Shoot fresh and dry weights and net photosynthetic rates were increased when plants were exposed to fluorescent lighting (control), red light, or a mixture of blue plus red, but were unaffected by blueonly radiation. Shoot elongation was significantly stimulated by red light whereas the combination of blue and red light was associated with the shortest shoots. However, the number of nodes did not differ among these treatments. Under monochromic blue or red light, sugar content and starch accumulation increased under the mixed-radiation treatment.  相似文献   

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Polyethylene glycol was added to the rooting medium ofmicropropagated grape shoots to induce water stress. At the end of the rooting stage, plantlets treated with 2% polyethylene glycol were compared with untreated control plantlets and greenhouse-grown plants. Leaves of treated plantlets had the highest deposition of epicuticular wax, followed by those of the greenhouse and control. Stomatal index did not vary among treatments. However, differences in leaf epidermal cell configuration were observed among treatments. The morphological changes of treated plantlets, including substantial deposition of epicuticular wax and modified leaf surface anatomy were associated with increasedex vitro survival after four weeks in the greenhouse.  相似文献   

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Polyethylene glycol was used to induce water stress of micropropagated Valiant grape. Reduced growth and slow rooting were observed in treated plantlets with 2, 4 and 6% polyethylene glycol as compared to control plantlets with no polyethylene glycol in the rooting medium. At high concentrations of 4 and 6%, leaves exhibited wilting and necrosis. At the 2% level, plantlets recovered and grew satisfactorily. Detached leaves of treated plantlets with 2% polyethylene glycol lost less water than controls when exposed to low humidity for 4 hours. Leaf anatomy of plantlets treated with 2% polyethylene glycol, control (in vitro plantlets) and greenhouse-grown plants were compared under light microscopy. Leaves from control plantlets contained larger mesophyll cells, lacked normal palisade layer formation, had greater intercellular pore spaces and fewer chloroplasts. Leaves from polyethylene glycol-treated plantlets, however, had smaller mesophyll cells, a more defined palisade layer, reduced intercellular pore space and the greatest number of chloroplasts. These results suggest that an osmoticum such as polyethylene glycol may be used to induce more normal leaf anatomy and reduced water loss in micropropagated Valiant grapes.Abbreviations BA 6-benzylaminopurine - FAA formalin-acetol-alcohol - MS Murashige & Skoog (1962) medium - MW molecular weight - NAA napthaleneacetic acid - PEG polyethylene glycol - TBA tertiary butyl alcohol  相似文献   

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Axillary shoot producing cultures were obtained from microcuttings and shoot tips of Calluna vulgaris cv. H.E. Beale. For cultures derived from microcuttings the highest multiplication rate of 38 shoots (5 mm or longer) was obtained on a reduced salt medium with the addition of 0.5 mgl-1 2-isopentenyladenine (2iP) during an 8 week subculture. For shoot tip derived cultures 0.2 mgl-1 6-benzyladenine (BA) was the best cytokinin and led to a multiplication rate of 26 for a 6 week subculture. The addition of 1 g/l casein hydrolysate to a multiplication medium enhanced shoot proliferation in presence of 0.5 mgl-1 BA.Despite various auxin treatments shoots formed no roots in vitro but rooted readily if transferred to a peat substrate ex vitro. A high rooting percentage (80%) was also obtained with shoots taken from the end of a multiplication phase and rooted directly. An additional subculture on low auxin containing media before transfer to peat substrate is recommended because the shoot condition can be improved in this way. A high number of rooted plantlets was produced, so the methods described will allow mass propagation.  相似文献   

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Nodal cuttings of D. alata L. Barzo fuerte and Florido, as well as of D. abyssinica Hoch, were cultured in vitro in order to assess the influence of the photoperiod on the production of microtubers. For both species, the highest number of microtubers was obtained under 16 and 24-h photoperiods, whereas larger microtubers were generally produced at 8-h photoperiod. In D. alata, further increase in microtuber size was observed in a culture medium where NH4NO3 was omitted. This effect was less noticeable in D. abyssinica.  相似文献   

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Achillea filipendulina (family Asteraceae) is widespread throughout temperate North America. In order to clean stock plants from endemic fungal and bacterial contaminations a method for large-scale propagation of A. filipendulina through meristem culture was sought and found and is described in this paper. The best conditions for propagating A. filipendulina was found to be MS (Murashige and Skoog) salt medium supplemented with 3% sucrose and 1 mg l–1 IAA (indole-3-acetic acid) plus 2 mg l–1 BA (6-benzyladenine) under 16 h of cool fluorescent light. Rooted plants were successfully acclimatized within a short time after propagating on this medium. The propagation via tissue culture did not affect plant's presentation. The use of clean stock plants made it possible to increased Israeli production of Achillea from about 150,000 stems a year to about 1,300,000 stems a year.  相似文献   

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This paper focuses on the uses and abuses of two terms, ‘White’ and ‘Black Turk’, which have been significant in the ways modern Turkish society and national identity have been defined and contested in recent decades. Initially emerging in social analysis in the 1990s, ‘White Turk’ was a metaphor for and critique of the class culture, subjectivity and worldviews of the ‘new middle classes’ in a period of rapid integration to neoliberalism and globalized capitalism. Over time, both White and Black Turks have come to be used as part of a politics of identity and a politics of authenticity to characterize who are seen as the ‘authentic self’ and inauthentic others of national identity and to assert different visions for the future of Turkish society. White Turk has been adopted as an identity by outspoken members of the media and business elite, whereas its binary opposite, Black Turk, has been appropriated by Islamist politicians of the Justice and Development Party (AKP) as a metaphor to characterize the marginalization and purported oppression of their conservative Muslim constituency. As White and Black Turks were adopted as self-proclaimed identities, they provided a basis for a culturalist depiction of Turkish society, contributing over time to an increasingly divisive politics. Even though the AKP initially used the reference to White and Black Turks to appeal to specific demands for inclusion, as it increased its grip on power, it also (hyper)politicized the terms to articulate nativist claims to authenticity. In recent years, this nativist populism has been used to justify increasing authoritarianism and to delegitimize belonging and political participation of those deemed inauthentic others of the body politics.  相似文献   

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A right-handed patient, aged 72, manifested alexia without agraphia, a right homonymous hemianopia and an impaired ability to identify visually presented objects. He was completely unable to read words aloud and severely deficient in naming visually presented letters. He responded to orthographic familiarity in the lexical decision tasks of the Psycholinguistic Assessments of Language Processing in Aphasia (PALPA) rather than to the lexicality of the letter strings. He was impaired at deciding whether two letters of different case (e.g., A, a) are the same, though he could detect real letters from made-up ones or from their mirror image. Consequently, his core deficit in reading was posited at the level of the abstract letter identifiers. When asked to trace a letter with his right index finger, kinesthetic facilitation enabled him to read letters and words aloud. Though he could use intact motor representations of letters in order to facilitate recognition and reading, the slow, sequential and error-prone process of reading letter by letter made him abandon further training.  相似文献   

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Stem sections from shoot cultures maintained in vitro were used to produce transgenic plants of the potato, Solanum tuberosum L. cv. Russet Burbank. Stem internode pieces inoculated with Agrobacterium tumefaciens containing coat protein genes from potato virus X and potato virus Y, produced shoots with a frequency of 60% in the absence of selection and 10% on medium containing 100 mg/l kanamycin monosulfate. Regenerated shoots were assayed for kanamycin resistance by placing stem segments on callus induction medium containing an increased level of kanamycin. Of a total 255 regenerated shoots, 47 (18%) were kanamycin resistant. Of the kanamycin resistant shoots, 25 (53%) expressed the PVX or PVY coat protein genes as assayed by enzyme-linked immunosorbent assay or Western immunoblot analysis.  相似文献   

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<正>We are pleased to announce a special issue on‘‘Computational Cardiology’’of the journal Genomics,ProteomicsBioinformatics(GPB),aiming to provide a platform for high-quality papers focusing on the topic and we invite submissions for this special issue(to be published in the fall of 2015).Dr.Benjamin Meder(University of Heidelberg and German Center for Cardiovascular Research–DZHK  相似文献   

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<正>The journal Genomics ProteomicsBioinformatics(GPB)is now inviting submissions for a special issue(to be published in the winter of 2015)on the topic of‘‘Biomarkers for Diseases’’.As an emerging index,disease biomarkers have demonstrated the potential application in diagnosis and prognosis.The detection of the disease indicators at molecular level,DNA,RNA  相似文献   

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Iron(II) [Fe(II)] oxidation coupled to denitrification is recognized as an environmentally important process in many ecosystems. However, the Fe(II)-oxidizing bacteria (FeOB) dominating autotrophic nitrate-reducing Fe(II)-oxidizing enrichment cultures, affiliated with the family Gallionellaceae, remain poorly taxonomically defined due to lack of representative isolates. We describe the taxonomic classification of three novel FeOB based on metagenome-assembled genomes (MAGs) acquired from the autotrophic nitrate-reducing enrichment cultures KS, BP and AG. Phylogenetic analysis of nearly full-length 16S rRNA gene sequences demonstrated that these three FeOB were most closely affiliated to the genera Ferrigenium, Sideroxydans and Gallionella, with up to 96.5%, 95.4% and 96.2% 16S rRNA gene sequence identities to representative isolates of these genera, respectively. In addition, average amino acid identities (AAI) of the genomes compared to the most closely related genera revealed highest AAI with Ferrigenium kumadai An22 (76.35–76.74%), suggesting that the three FeOB are members of this genus. Phylogenetic analysis of conserved functional genes further supported that these FeOB represent three novel species of the genus Ferrigenium. Moreover, the three novel FeOB likely have characteristic features, performing partial denitrification coupled to Fe(II) oxidation and carbon fixation. Scanning electron microscopy of the enrichment cultures showed slightly curved rod-shaped cells, ranging from 0.2-0.7 μm in width and 0.5–2.3 μm in length. Based on the phylogenetic, genomic and physiological characteristics, we propose that these FeOB represent three novel species, ‘Candidatus Ferrigenium straubiae’ sp. nov., ‘Candidatus Ferrigenium bremense’ sp. nov. and ‘Candidatus Ferrigenium altingense’ sp. nov. that might have unique metabolic features among the genus Ferrigenium.  相似文献   

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Chronic oral anticoagulant treatment is obligatory in patients (class I) with mechanical heart valves and in patients with atrial fibrillation with CHADS2 score >1. When these patients undergo percutaneous coronary intervention with placement of a stent, there is also an indication for treatment with aspirin and clopidogrel. Unfortunately, triple therapy is known to increase the bleeding risk. For this group of patients, the bottom line is to find the ideal therapy in patients with indications for both chronic anticoagulation therapy and percutaneous intervention to prevent thromboembolic complications such as stent thrombosis without increasing the risk of bleeding. (Neth Heart J 2010;18:444-50.)  相似文献   

20.
Physiological (metabolite analysis) and molecular (gene expression) approaches were used to understand the mechanism underlying russet formation in response to the application of GA3 and CPPU (Forchlorfenuron) in a Japanese table grape cultivar ‘Shine Muscat’. Several different concentrations of GA3 and GA3?+?CPPU [25?mg?L?1 GA3 (A), 25?mg?L?1 GA3?+?5?mg?L?1 CPPU (B), 25?mg?L?1 GA3?+?10?mg?L?1 CPPU (C), and 25?mg?L?1 GA3?+?15?mg?L?1 CPPU (D)] were applied to grape berry clusters at two weeks after flowering (WAF). No russet was observed on the berries treated with the ‘C’ combination. Lower levels of phenylalanine ammonia-lyase (PAL) activity was observed in the treated samples, relative to the untreated material. Reduced peroxide (POD) activity was also observed in response to different treatments, while the expression of Peroxidase 17 and Phenylalanine ammonia-lyase G1 genes mirrored lignin content. Increased activity of 4-coenzyme A ligase (4CL) may contribute to decreasing the level of russet and help to improve grape berry quality.  相似文献   

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