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171.
Tim Gruffydd-Jones Diane Addie Sándor Belák Corine Boucraut-Baralon Herman Egberink Tadeusz Frymus Katrin Hartmann Margaret J. Hosie Albert Lloret Hans Lutz Fulvio Marsilio Maria Grazia Pennisi Alan D. Radford Etienne Thiry Uwe Truyen Marian C. Horzinek 《Journal of Feline Medicine and Surgery》2009,11(7):605-609
172.
Etienne Thiry Diane Addie Sándor Belák Corine Boucraut-Baralon Herman Egberink Tadeusz Frymus Tim Gruffydd-Jones Katrin Hartmann Margaret J. Hosie Albert Lloret Hans Lutz Fulvio Marsilio Maria Grazia Pennisi Alan D. Radford Uwe Truyen Marian C. Horzinek 《Journal of Feline Medicine and Surgery》2009,11(7):615-618
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174.
Marje Särekanno Jüri Kadaja Katrin Kotkas Viive Rosenberg Viacheslav Eremeev 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(2):114-124
Abstract In the current multiplication technique first-generation seed tubers produced in the field by transplanting plants raised on peat in plastic rolls from plants cultured by repetitive multiplication using tip- and stem-cuttings and truncated plants are compared with in vitro micro-plants from the aspect of obtaining optimal-sized, disease-free seed tubers. The objective of the study is to compare the dynamics of total plant dry mass and tuber dry mass of field-grown potato plants, and analyse the effect of the year and variety. Two local late-maturing potato varieties, Ants and Vigri, were used in the study. The field experiments were carried out in 2005–2007. Significant impact of the multiplication method and experimental year on total plant dry mass and tuber dry mass was observed. The plants multiplied in vitro from micro-cuttings produced lower total dry mass and also lower tuber dry mass per m2. The plants multiplied by tip- and stem-cuttings as well as truncated plants proved to be more adaptable to unfavourable weather conditions than in vitro plants; in a favourable year, however, the differences were insignificant. In the early phase of growth the ratio of the tuber dry mass to total plant dry mass increased more rapidly in the case of in vitro plants, whereas by the end of the growing season the relevant ratio was similar for all multiplication methods and years. All developed multiplication methods are suitable for practical seed potato production in the field and ensure a reasonable potato crop. 相似文献
175.
Ann Katrin Holtekjølen Stefan Sahlstrøm Svein Halvor Knutsen 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(1):67-74
Abstract Phenolic contents and corresponding antioxidant activities were studied in covered whole-grain flours of Norwegian barley varieties and in two different pearling fractions. In covered whole-grain flours the summarized amount of phenolics (Σ-P) ranged from 481–676 mg gallic acid equivalent (GAE)/100 g dry matter (DM) and the corresponding total antioxidant activities (Σ-FRAP) between 6.1–8.7 mmol Fe3 +/100 g DM. About 50% of the phenolics in these samples were easily extractable (free). Upon pearling a general decrease in both Σ-P and Σ-FRAP was seen in the pearled samples, while the ratio between free and bound phenolics was similar or increased to those in the covered whole-grain samples. The hulls had the highest Σ-P and Σ-FRAP and were dominated by bound phenolics. Despite accounting for only 10–20% of the total grain weight, the hulls typically contributed to 45% of the total antioxidant capacity measured in the covered whole-grain flours. Pearling makes it possible to obtain barley fractions with different amounts of phenolics, different ratios of free and bound phenolics, and thus different antioxidant activities. 相似文献
176.
Katrin Rosenvald Ivika Ostonen Veiko Uri Mats Varik Leho Tedersoo Krista Lõhmus 《European Journal of Forest Research》2013,132(2):219-230
The influence of forest ageing on fine-root morphology and relations between fine-root and leaf characteristics is poorly studied. The aim of this study was to analyse age-driven changes in ectomycorrhizal roots (EcM roots) and leaf morphology in a chronosequence of silver birch (Betula pendula Roth.), which would provide a better understanding of adaptation responses and acclimation capacity of tree roots and leaves. The chronosequence included six age classes (3, 6, 14, 32, 45, and 60 years.). All stands had regenerated naturally and grew in a highly productive Oxalis forest site type in Estonia. Most changes in the morphology of EcM roots and leaves of silver birch occur faster at a young age. The functional parameters—mean specific area of EcM root (SRA) and leaf specific area (SLA) as well as leaf N—decreased with age. EcM root SRA and specific root length (SRL) decreased with stand age as a result of increased mean diameter and tissue density. In age classes of 6, 14, and 32 years, the total number of dominating EcM taxa was 34, and the distribution of four different dominating EcM exploration types (contact-, short-, medium-, long-distance) was similar. We conclude that high values of SRA, SLA, and leaf N measured in young silver birch stands indicate high activity of physiological processes necessary for fast-growing young trees. A decrease of SLA and SRA and N in the chronosequence of fertile stands of silver birch is most probably caused by down-regulation of growth, affecting simultaneously leaves and fine roots. 相似文献
177.
Iron (Fe) toxicity is a nutritional disorder that affects lowland rice (Oryza sativa L.). The occurrence of excessive amounts of reduced Fe(II) in the soil solution, its uptake by the rice roots, and its transpiration‐driven transport result in elevated Fe(II) concentrations in leaf cells that catalyze the formation of reactive oxygen species. The oxidative stress causes rusty brown spots on leaves (bronzing) and the reduction of biomass and yield. While the use of resistant genotypes is the most promising approach to address the problem, the stress appears to differentially affect rice plants as a function of plant age, climatic conditions, stress intensity and duration, and the prevailing adaptation mechanism. We comparatively assessed 21 contrasting 6‐week‐old rice genotypes regarding their response (symptom score, biomass, Fe concentrations and uptake) to a 6 d iron pulse of 1500 mg L–1 Fe(II). Eight selected genotypes were further compared at different stress intensities (0, 500, 1000, and 1500 mg L–1 Fe(II)) and at different developmental stages (4‐, 6‐, and 8‐week‐old plants). Based on Fe‐induced biomass reduction and leaf‐bronzing score, the tested spectrum was grouped in resistant and sensitive genotypes. Linking bronzing scores to leaf iron concentrations allowed further differentiation into includer and excluder types. Iron precipitation on roots and organ‐specific iron partitioning permitted to classify the adaptation strategies into root exclusion, stem and leaf sheath retention, and leaf blade tissue tolerance. The effectiveness of these strategies differed with stress intensity and developmental stage. The reported findings improve the understanding of Fe‐stress response and provide a basis for future genotype selection or breeding for enhancing Fe‐toxicity resistance in rice. 相似文献
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179.
Alexander Pesic Heike I. Baumann Katrin Kleinschmidt Paul Ensle Jutta Wiese Roderich D. Süssmuth Johannes F. Imhoff 《Marine drugs》2013,11(12):4834-4857
New isolates of Streptomyces champavatii were isolated from marine sediments of the Gotland Deep (Baltic Sea), from the Urania Basin (Eastern Mediterranean), and from the Kiel Bight (Baltic Sea). The isolates produced several oligopeptidic secondary metabolites, including the new octapeptide champacyclin (1a) present in all three strains. Herein, we report on the isolation, structure elucidation and determination of the absolute stereochemistry of this isoleucine/leucine (Ile/Leu = Xle) rich cyclic octapeptide champacyclin (1a). As 2D nuclear magnetic resonance (NMR) spectroscopy could not fully resolve the structure of (1a), additional information on sequence and configuration of stereocenters were obtained by a combination of multi stage mass spectrometry (MSn) studies, amino acid analysis, partial hydrolysis and subsequent enantiomer analytics with gas chromatography positive chmical ionization/electron impact mass spectrometry (GC-PCI/EI-MS) supported by comparison to reference dipeptides. Proof of the head-to-tail cyclization of (1a) was accomplished by solid phase peptide synthesis (SPPS) compared to an alternatively side chain cyclized derivative (2). Champacyclin (1a) is likely synthesized by a non-ribosomal peptide synthetase (NRPS), because of its high content of (d)-amino acids. The compound (1a) showed antimicrobial activity against the phytopathogen Erwinia amylovora causing the fire blight disease of certain plants. 相似文献
180.
Thomas Flegel Marie-Kerstin Müller Katrin Truar Carina L?ffler Gerhard Oechtering 《The Canadian veterinary journal. La revue veterinaire canadienne》2013,54(10):969-973
Clinical features, myelography, and computed tomography imaging findings as well as neurological outcome with and without surgery in 5 pug dogs with thoracolumbar arachnoid diverticula are described. Short-term prognosis after surgical therapy may not be as good as reported for other canine breeds, since immediate postsurgical deterioration is possible. Improvement of neurological deficits beyond the presurgical status may take several months. 相似文献