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91.
Van Eerd LL Stephenson GR Kwiatkowski J Grossmann K Hall JC 《Journal of agricultural and food chemistry》2005,53(4):1144-1151
The physiological and biochemical basis for quinclorac resistance in a false cleavers (Galium spurium L.) biotype was investigated. There was no difference between herbicide resistant (R) and susceptible (S) false cleavers biotypes in response to 2,4-D, clopyralid, glyphosate, glufosinate-ammonium, or bentazon. On the basis of GR(50) (growth reduction of 50%) or LD(50) (lethal dose to 50% of tested plants) values, the R biotype was highly resistant to the acetolactate synthase (ALS) inhibitor, thifensulfuron-methyl (GR(50) resistance ratio R/S = 57), and quinolinecarboxylic acids (quinclorac R/S = 46), resistant to MCPA (R/S = 12), and moderately resistant to the auxinic herbicides picloram (R/S = 3), dicamba (R/S = 3), fluroxypyr (R/S = 3), and triclopyr (R/S = 2). The mechanism of quinclorac resistance was not due to differences in [(14)C]quinclorac absorption, translocation, root exudation, or metabolism. Seventy-two hours after root application of quinclorac, ethylene increased ca. 3-fold in S but not R plants when compared to controls, while ABA increased ca. 14-fold in S as opposed to ca. 3-fold in R plants suggesting an alteration in the auxin signal transduction pathway, or altered target site causes resistance in false cleavers. The R false cleavers biotype may be an excellent model system to further examine the auxin signal transduction pathway and the mechanism of quinclorac and auxinic herbicide action. 相似文献
92.
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 [molc/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
93.
94.
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
95.
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
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98.
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.
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.
am ¶rt;au , , ,Solanum tuberosum L., 1964 .相似文献
99.
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
100.
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