Die Oberflächenladung der Ton-Humusfraktion aus Schwarzerden als Funktion von pH und Ca-Konzentration     

Klaus Bckenhoff  Stefan Gall  Walter R. Fischer 《植物养料与土壤学杂志》1997,160(2):341-346

Surface charge of clay-humus fractions from Chernozems as a function of pH and Ca-concentration The charge characteristics of clay-humus fractions from A-horizons of several Chernozems as a function of Ca concentration and pH of the soil solution was investigated. The surface charge was measured by titration with charge compensating polyelectrolytes; the endpoint was at zero potential. A logarithmic dependence of the surface charge [mol_c/kg] on the Ca concentration of the soil solution in the range ? 2 mmol/L was observed. The influence of pH on the surface charge was almost linear over a wide range of pH-values, the change in pH-dependent charges being most pronounced for the horizons with low Ca saturation on the exchange sites. It was also found that the competition between protons and Ca ions for the exchange sites leads to a distinct decrease of the influence of Ca concentration on the surface charge in acid environment. The reason for slaking of the soil surface and of the displacement of clay-humus particles in Chernozems could be attributed to an increase in surface charge with decreasing Ca concentrations after leaching of lime. According to the present findings the drop in mobility of the clay-humus fractions during acidification could be explained by a charge compensating effect of protons and aluminium ions.  相似文献   

Taxonomic status and geographic provenance of germplasm accessions in the Solanum nigrum L. complex: AFLP data     

Klaus J. Dehmer  Karl Hammer 《Genetic Resources and Crop Evolution》2004,51(5):551-558

Amplified Fragment Length Polymorphisms (AFLPs) were employed within the taxonomically difficult Solanum nigrum L. complex in order to characterize the genetic diversity present in a collection of the Gatersleben Genebank, to classify taxonomically unknown material, and to correlate the clustering of the examined accessions with their geographic origin. The results from AFLP analyses using two primer combinations on 44 entries from five species led to the detection of four major clusters, simultaneously uncovering significant differences in the levels of genetic diversity within or between species. S. americanumexhibited the highest infraspecific variation despite close geographic origins, simultaneously being placed in a clearly separated cluster in comparison to the other examined species of the complex. In addition, these other species showed even less interspecific variation than was found at the infraspecific level in S. americanum. In terms of taxonomy, the application of AFLPs helped in the classification of 13 black nightshade accessions formerly only listed as Solanum sp. This also was confirmed by morphological determination. Furthermore, one accession formerly classified as S. physalifolium var. nitidibaccatum i) clustered with AFLPs and ii) was identified morphologically as S. villosum. Contradictory classifications remain for two further entries from the same species, found within the S. nigrum cluster after AFLP analyses, while belonging to S. physalifolium var. nitidibaccatum according to herbarium specimen. Finally, as indicated by the information on provenance in geographically separated subclusters in S. americanum and partially in S. villosum, clues on the currently unknown origin of accessions from the genebank seem feasible by AFLP data.  相似文献   

Irrigation with plant extracts in ecofarming increases biomass production and mineral and organic nitrogen content of plants     

Gerhard Gramss  Klaus‐Dieter Voigt  Hans Bergmann 《植物养料与土壤学杂志》2003,166(5):612-620

Seedlings of alfalfa, rape, spinach, and wheat, potted on sandy soil, were irrigated with an aqueous extract of pea shoot (PE, 9.84 g dry weight l^–1) or a solution of Ca, K, Mg, P, and NO₃‐N salts (SS) in a concentration similar to that in PE, for 31–48 days. In comparison to water‐irrigated controls, both SS and PE treated plants showed nearly equal increases in shoot dry weight (29–40 %), whereas PE‐treated plants had higher fresh weights (38–84 %) due to increased succulence. Treatment with SS did not enhance, but sometimes even reduce, the concentrations of Ca, K, Mg, and several trace elements in shoot tissues. In contrast, PE‐treated plants had higher Ca, K, Mg, and organic N, but lower As and Ni contents and were thus of higher nutritive value. Reduced contents of metals in plant tissue correlated with their reduced solubility in the soil solution, which was not due to changes in pH. Fertilizer components such as K and Mg (metals of lower exchange intensity) were incorporated into the soil to release Ca, Sr, and Ba (metals of higher exchange intensity) and reduce the solubility of most trace elements and metal‐complexing humic substances. In addition, application of Ca precipitated heavy metals and humic complexes directly from the soil solution. This effect was partially overcome by PE. Its carboxylic acids could act as phytochelators of metal ions and as mobilizers of the highly diffusible humic substances which carry metals to roots. It is concluded that continuous PE application replaces the quantities of Ca, K, Mg, P, and organic N, but not of NO₃‐N consumed during plant growth. Using PE does not add any relevant quantities of toxic metals to the plant‐soil system.  相似文献   

RADIOLOGIC EVALUATION OF SPAVIN IN YOUNG TROTTERS     

Klaus Hartung  Beate Münzer  Horst Keller 《Veterinary radiology & ultrasound》1983,24(4):153-155

Tarsal radiographs of 134 trotters were made prior to training. Radiographs were evaluated for changes commonly associated with spavin. Spavin, if present, was graded as mild, moderate, or severe. Sone of the 134 horses were radiographed annually for one, two, or three years. Radiographs of the 134 horses were compared with radiographs of 141 additional horses in which spavin had been diagnosed clinically. Only 66 of the 134 trotters (50.4%) had normal tarsal radiographs at the time of initial examination; the other 65 had some radiographic evidence of spavin. The incidence and severity of radiographic changes identified in a group of horses in which spavin was diagnosed clinically. Thus, the present results suggest that tarsal radiography is of little value in establishing the diagnosis and prognosis of spavin in trotters.  相似文献   

Bemühungen der organisierten Rinderproduktion urn die Verbesserung der Fruchtbarkeit beim Rind     

Klaus Meyn 《Reproduction in domestic animals》1993,28(6):423-426

Inhalt: Der vorliegende Beitrag beschreibt den Stand der Datenermittlung und Zuchtwertschätzung für die Reproduktionsmerkmale beim Rind in Deutschland. Des weiteren werden Probleme der Seuchenkontrolle und der EG-Gesetzgebung im Bereich der KB und des Embryotransfers beschrieben. Abschlieβend werden die Aktivitäten der Arbeitsgemeinschaft Deutscher Rinderzüchter zur Verbesserung der Aus- und Weiterbildung des Besamungspersonals dargestellt. Seit mehr als 20 Jahren erhalten die Bemühungen der ADR um die Verbesserung des Fortpflanzungsgeschehens in den deutschen Rinderbeständen hervorragende Unterstützung durch Dr. Dr. h.c. R. Hahn, Neustadt a.d.Aisch.  相似文献   

Isolierung von Jurubin,Neochlorogenin und Paniculogenin ausSolanum torvum SwartzSolanum-Alkaloide,LXXXIV. Mitteilung     

Klaus Schreiber  Helmut Ripperger 《Genetic Resources and Crop Evolution》1967,15(1):199-204

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Eiweißuntersuchungen am Getreide- und Leguminosen-Sortiment Gatersleben     

Peter Hanelt  Armin Rudolph  Karl Hammer  Hans -Wolfgang Jank  Klaus Müntz  Friedrich Scholz 《Genetic Resources and Crop Evolution》1978,26(2):133-161

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Bibliographie der Gibberellin-Untersuchungen an Kulturpflanzen     

Günther Sembdner  Gernot Schneider  Jürgen Weiland  Klaus Schreiber 《Genetic Resources and Crop Evolution》1965,13(1):137-144

Zusammenfassung Als I. Mitteilung einer Serie über die Bibliographie der Gibberellin-Untersuchungen an Kulturpflanzen werden für die Kartoffelpflanze,Solanum tuberosum L., die bis 1964 vorliegenden Veröffentlichungen in alphabetischer Anordnung aufgeführt.

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Summary In the I. part of a series on the bibliography of the gibberellin investigations on cultivated plants the papers concerning the potato plant,Solanum tuberosum L., published till 1964 are catalogued alphabetically.

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am ¶rt;au , , ,Solanum tuberosum L., 1964 .

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Pflanzenproteine: Ihre wirtschaftliche Bedeutung und Nutzung     

Müntz  Klaus 《Genetic Resources and Crop Evolution》1975,23(1):223-239

Genetic Resources and Crop Evolution - Photoautotrophe Organismen (Pflanzen) sind die primären Proteinproduzenten auf der Erde. Die Erzeugung von Tier- und Mikrobenprotein geht von organischen...  相似文献   

Hemophilia B (factor IX deficiency) with concomitant factor XII degradation in a male crossbreed cat     

Lutze G  Kutschmann K  Fürst K  Schneppenheim R 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(5-6):255-260

A male cat suffered from a severe haemorrhagic disorder manifesting as deep, partly infected cutaneous haematomas, enhanced and prolonged bleeding after injuries and subsequent lameness at several occasions. Bleeding resulted in severe anaemia with haematocrit falling to as low as 0.10 L/L. Haemophilia B was diagnosed based on factor IX deficiency with a functional residual activity of 5% and factor IX antigen of 8%, respectively. Additionally, factor XII activity was reduced to 32% of normal. The mutation 31217G==>A in exon 8 of the factor IX gene, predicting the amino acid exchange G366R was identified as the cause of moderate factor IX deficiency. This is the first mutation identified in cats with haemophilia B. Treatment was limited to local therapy and palliation, insufficient to prevent lethal outcome due to severe anaemia.  相似文献