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141.
Linke D Bouws H Peters T Nimtz M Berger RG Zorn H 《Journal of agricultural and food chemistry》2005,53(24):9498-9505
Peanut shells, a major waste stream of food processing, served as a renewable substrate for inducing the production of laccases by basidiomycetes. Of 46 surface cultures examined, 29 showed laccase activity under the experimental conditions. The edible fungus Pleurotus sapidus was selected as the most active producer, immobilized on the shells, and cultivated in the fed-batch mode. A continuous rise in laccase activity was found, indicating the inducibility of laccase secretion by the peanut shells and the reusability of the mycelium. Two laccase isoenzymes were purified by decoupled 2-D electrophoresis, and amino acid sequence information was obtained by electrospray ionization tandem mass spectrometry. cDNAs of the corresponding gene and another laccase were cloned and sequenced using a PCR-based screening of a synthesized P. sapidus cDNA library. Data bank searches against public databases returned laccases of P. ostreatus and P. sajor-caju as the best hits. The potential use of laccases by the food industry is discussed. 相似文献
142.
Yu-Chun Qi Yun-She Dong Ji-Yuan Liu Manfred Domroes Yuan-Bo Geng Li-Xin Liu Xing-Ren Liu Xiao-hong Yang 《Soil & Tillage Research》2007,94(2):310-320
Chinese grasslands have undergone great changes in land use in recent decades. Approximately 18.2% of the present arable land in China originated from the cultivation of grassland, but its impact on the carbon cycle has not been fully understood. This study was conducted in situ for 3 years to assess the comprehensive effects of cultivation of temperate steppe on soil organic carbon (SOC) and soil respiration rates as well as ecosystem respiration. As compared with those in the Stipa baicalensis steppe, the SOC concentrations at depths of 0–10 and 10–20 cm in the spring wheat field were found to have decreased by 38.3 and 17.4% respectively from 29.5 and 21.9 g kg−1 to 18.2 and 18.1 g kg−1 after a cultivation period of 30 years. Accordingly, the total amounts of soil respiration through the growing season (from April to September) in 2002, 2003 and 2004 were 265.2, 282.2 and 237.4 g C m−2 respectively in the spring wheat field, which were slightly lower than the values of 342.2, 412.0 and 312.1 g C m−2 in the S. baicalensis steppe, while ecosystem respiration of 690.9, 991.2 and 569.6 g C m−2 respectively in the spring wheat field were markedly higher than those of 447.0, 470.9 and 429.7 g C m−2 in the steppe plot. Similar seasonal variations of ecosystem respiration and soil respiration existed in both sample sites. Respiration rates were higher and greater differences existed in both ecosystem respiration and soil respiration during the exuberant growth stage of plants (from mid-June to mid-August). However, in the slower-growth period of the growing season (before late May and after late August), the CO2 effluxes of the two sample sites were similar and remained at a relatively low level. The results also showed that ecosystem respiration and soil respiration were under similar environmental controls in both sample sites. Soil water content at a depth of 0–10 cm and soil temperatures at 5 and 10 cm were the main factors affecting the variations in ecosystem respiration and soil respiration rates in droughty years of 2002 and 2004 and in the rainy 2003, respectively. This study suggests that the conversion of the grassland to the spring wheat field has increased the carbon loss of the whole ecosystem due to the change of vegetation cover type and significantly reduced the carbon storage of surface soil. In addition, the tillage of grassland had different effects on ecosystem respiration and soil respiration. The effects were also dissimilar in different growth stages, which should be fully considered when assessing and predicting the effects of cultivation on the net CO2 balance of grassland ecosystems. 相似文献
143.
144.
Journal of Soils and Sediments - 相似文献
145.
Industrial crops provide a possibility for utilization of heavy metal polluted soils. Knowledge of the factors which affect metal uptake by crops is therefore essential in order to develop concepts for the management of such soils. In pot experiments the uptake of Zn by oilseed rape increased considerably with the Zn supply. The increase of Zn uptake was counteracted partly by S. This protective effect of S was, however, not related to Zn retention in the roots. 相似文献
146.
Hans J. M. van Grinsven Bart G. Wesselink Manfred Schroeder Nico van Breemen 《植物养料与土壤学杂志》1991,154(3):181-188
Solute budgets and nitrogen use were quantified in two 400 m2 forested lysimeters in St. Arnold, Nordrhein-Westfalen. The lysimeters are covered by a mixture of oak-beech and Weymouth pine, respectively. The average bulk deposition between May 1985 and May 1987 of NH, SO and NO3 was 1.1, 1.7, and 0.4 kmolc ha?1 yr?1 in the deciduous stand and 2.1, 2.1, and 0.8 kmolc ha?1 yr?1 in the coniferous stand. The input of N is almost completely retained in the deciduous stand. In the coniferous stand about 30% of this N-input is leached as NO3. Due to N-transformations, total proton turnover is 4.4 kmolc ha?1 yr?1 in the coniferous stand and only 2.5 kmolc ha?1 yr?1 in the deciduous stand. Ca-mobilization is the major acid buffering process in both lysimeters. Only the deciduous stand was limed in 1980 (90 kmolc/ha). Mobilization of Al is only relevant down to a soil depth of 30 cm. Below a 30 cm depth, Al is immobilized. The amounts of exchangeable and silicate-bound Ca in the soil underlying the coniferous stand are very small, but no evidence was found for explanation of the observed high Ca-mobilization by artificial Ca-sources. 相似文献
147.
Compost of separately collected green yard and organic household wastes may contain high amounts of Zn. Hence, substrates basing on compost can result in Zn phytotoxicity. The aim of the investigations was to identify a suitable reagent to characterize phytoavailable Zn in compost-peat substrates. Petunia hybrids were cultivated in compost-peat substrates with increasing Zn amounts (basic load, 400, 800, 1600 mg kg?1 d.m. aqua regia soluble). Extractable Zn was determined by extraction of fresh and dried substrates with H2O, 1 M NH4NO3, 0.1 M CaCl2, 1 M NH4OAc, and CaCl2-DTPA (0.01 M + 0.002 M). The Zn content of plants increased significantly with increasing Zn application and decreasing pH. The result of CaCl2 and NH4OAc extraction reflected the influence of pH on Zn phytoavailability quite well and the correlation with the plant Zn content was very good. Extraction with H2O and NH4NO3 did not give acceptable results. Extraction with CaCl2-DTPA was inconsistent for all trials and thus not suitable. The percentage of CaCl2-extractable Zn in relation to the aqua regia soluble content at the same pH varied over the trials. Thus, the phytoavailable content of the substrates is influenced by additional factors, besides Zn supply and pH. The result of CaCl2 extraction of dried substrates resulted in the best reflection of Zn phytoavailability and was used for all further investigations, including determination of critical values of phytotoxic Zn. Plant yield was not influenced by the Zn treatments. However, Zn induced chlorosis of petunias occurred at a plant Zn content > 160 mg kg?1 d.m. and a phytoavailable Zn content in the substrate > 6 mg l?1 in CaCl2 extract and > 2.6 mg l?1 in NH4OAc extract, respectively. 相似文献
148.
Prof. Dr. Manfred Dambroth Prof. Dr. Walter Hondelmann 《Genetic Resources and Crop Evolution》1981,29(1):41-45
Summary The occurrence of old land-races indigenous to the territory of the Federal Republic of Germany under special consideration of their availability is being described. Some typical features of the findings are explained.
Einige Bemerkungen zur Sammlung von für das Gebiet der Bundesrepublik Deutschland indigenen Landsorten von Kulturpflanzen
Zusammenfassung Das Vorkommen alter Landsorten, die für das Gebiet der Bundesrepublik Deutschland indigen sind, wird unter besonderer Berücksichtigung ihrer Verfügbarkeit beschrieben. Einige charakteristische Besonderheiten der Nachweise werden erläutert.
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149.
Ana Alves António Santos Denilson da Silva Perez José Rodrigues Helena Pereira Rogério Simões Manfred Schwanninger 《Wood Science and Technology》2007,41(6):491-499
A total of 910 maritime pine (Pinus pinaster Aiton) wood discs, belonging to a genetic trial of 80 families with 11–12 trees per family, were used in this study. A near
infrared (NIR) partial least squares regression (PLSR) model for the prediction of Kappa number of Pinus pinaster Aiton pulps obtained from samples pulped under identical conditions was calculated. Very good correlations between NIR spectra
of maritime pine pulps and Kappa numbers in the range from 58 to 100 were obtained. Besides the raw spectra, spectra pre-processed
with ten methods were used for PLS analysis (cross validation with 57 samples), showing that even after test set validation
(with 34 samples) no model decision could be made due to almost identical statistics. The final evaluation that proved the
predictive power of the models by predicting pulps with unknown Kappa numbers allowed choosing a model according to a minimal
number of outliers found during this process. The minimum–maximum normalized spectra in the wave number range from 6,110 to
5,440 cm−1 used for the calculation gave the best model with a root mean square error of prediction of 2.3 units of Kappa number, a
coefficient of determination of 95.9%, and one PLS component. The percentage of outliers during evaluation was 0.9%. 相似文献
150.
Leonie F. Herkommer Manfred Henrich Christiane Herden Martin J. Schmidt 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(4):1570-1575
Periventricular nodular heterotopia is a common neuronal malformation in humans, often leading to epilepsy and other neurologic diseases. A 2-month-old female Chihuahua weighing 750 g was examined because of a history of epileptic seizures and abnormalities in gait and behavior. Results of the clinical examination were consistent with a multifocal neurologic disease with localization in the forebrain and spinovestibular system. The magnetic resonance imaging showed multiple bilateral periventricular nodules isointense to gray matter and ventriculomegaly. Histopathological and immunohistological examination of the brain revealed that periventricular nodules consisted of neurons, fewer astrocytes, and some oligodendroglia consistent with periventricular nodular heterotopias. 相似文献