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Kristina Bachteler Monika Riedel Nikolaus Merkt Wolfgang Schies Jutta Fröhlin Jens Wünsche 《Journal of plant nutrition》2015,38(6):839-853
Berry shrivel and bunch stem necrosis are the economically most important physiological disorders of grapevine. The nutritional status of the plant is considered as one of the main elicitors for the occurrence of these disorders. For foliar fertilization trials, two vineyards that had previously been affected by both diseases were selected in Southwest Germany, one with the variety ‘Zweigelt’ and one with Pinot Blanc. By the use of potassium, magnesium, and calcium foliar fertilizers, a rapid increase of different nutrients in the plants should be caused and the effects on the diseases observed. In 2010, no significant differences in the fertilization treatments were found for both varieties. In ‘Pinot Blanc’, significantly more berries were affected by berry shrivel in 2011 in plots treated with calcium fertilizer compared to those treated with potassium and magnesium. Plots with magnesium fertilizer showed significantly less berries affected by berry shrivel than the untreated control. 相似文献
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Wolfgang Leipnitz Horst Käding Gisbert Schalitz 《Archives of Agronomy and Soil Science》2013,59(4):283-289
Langjährige Beobachtungen der Witterungsfaktoren Temperatur und Niederschlag auf Ertrag und Pflanzenbestand von zwei Dauergrünlandstandorten verschiedener Klimagebiete wurden ausgewertet. Anlaß war das Phänomen, daß im Erzgebirge der Ertrag trotz hoher Stickstoffdungung nach dem 3. Versuchsjahr sukzessive abfiel und nach dem 12. Jahr wieder anstieg. Als Vergleich bot sich nahezu gleich bewirtschaftetes Grünland im Havelländischen Luch an. Die Ursache fur die Ertragsdepression wurde zunächst in einer Umschichtung der Pflanzenbestände vermutet. Schließlich wurde ein Zusammenhang zwischen Witterung und Ertrag am Beispiel der Abweichungen von den Mittelwerten gefunden. 相似文献
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Wolfgang Ahlf Henner Hollert Helga Neumann-Hensel Mathias Ricking 《Journal of Soils and Sediments》2002,2(1):37-42
The recommendations presented in this paper use an integrated hierarchical approach combining toxicological, chemical and
ecological information to assess and evaluate the quality of sediments. For this reason, biological methods, in combination
with the tools of chemical analysis, are given priority when examining the quality of the sediment to establish adverse effects.
The trigger is the biotest, instead of chemical methods commonly used. The individual methods are presented for a German approach
and can be adopted to other countries by applying ISO, OECD methods. Support is provided on how to best integrate data generated
using different assessment tools. Keywords: Bioassays; biological and chemical analysis; ecotoxicology; integrated assessment;
sediment assessment; sediment quality; stepwise strategy 相似文献
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Frost tolerance is a main component of winter-hardiness and improving it would promote faba bean (Vicia faba L.) cropping in cool-temperate regions. In many species, leaf fatty acid composition was found to be related to frost tolerance.
The objective of this study was to determine, in a representative sample of genotypes, the effect of hardening on leaf and
stem (1) frost tolerance and (2) fatty acid composition, and to seek correlations between them. First leaf, second leaf and
stem of 31 faba bean genotypes were analyzed after hardening and without hardening. High frost tolerance of known winter genotypes
and several experimental lines was shown. Hardening had a significant, positive effect on frost tolerance of all three organs.
Stems were on average more frost tolerant than leaves. Hardening induced significant changes in the fatty acid composition:
oleic acid decreased significantly in leaves by 3.24% and in stems by 1.77%, whereas linolenic acid increased in leaves by
6.28% and in stems by 9.06%. In stems, correlations between frost tolerance and fatty acid composition were not significant.
Correlation coefficients strongly indicated that non-hardened oleic acid content, changes in oleic acid and in linoleic plus
linolenic acid content in leaves partly explained their frost tolerance; 0.347 (P < 0.1) < |r| < 0.543 (P < 0.01). The results corroborate the importance of using genetic differences in the fatty acid metabolism in breeding grain
legumes for frost tolerance. 相似文献
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The photochemical reactions of phosmet, an organophosphorus insecticide used for plant protection and for control of ectoparasites on productive livestock, were studied in the presence of wool wax. Induced by UV light, phosmet features numerous degradation pathways as well as photoaddition reactions with lipid structure moieties. In model irradiation experiments of phosmet in mixtures of solvents (cyclohexane, cyclohexene, 2-propanol) and fatty acid methyl esters (methyl stearate, methyl oleate, 12-hydroxymethyl stearate), both adjusted to the hydroxyl and iodine values of wool wax, half-lives were determined to be approximately 7 and 16 h, respectively. Irradiation of phosmet on crude sheep wool resulted in a degradation rate of 65% after 24 h. In tracer studies with stable isotope labeled phosmet ([15N]phosmet) in commercial lanolin and on raw sheep wool, employing a sunlight simulator and natural sunlight, wool wax bound phosmet was formed. After extraction and measurement by elemental analyzer/isotope ratio mass spectrometry, delta15N values of the phosmet-free wool wax fractions were notably increased as compared to the value of natural lanolin. Calculated from the delta15N values, an average of 13.9/15.6% (sunlight simulator/natural sunlight) was bound to wool wax lipids after irradiation of thin films of commercial lanolin. In experiments with sheep wool, 13.2 and 15.4%, respectively, were detected as wax-bound. 相似文献
10.
Copper uptake from foliar applied copper sources by wheat plants Cu uptake of young wheat plants from foliar applied Cu sources such as Cu sulfate, Cu oxide chloride, Cu EDTA, and Cu lignosulphonate was studied over periods of 48 hours. Compared to Cu oxide chloride, Cu uptake from the remaining Cu compounds was approximately 3 times higher. Additives increased the adhesion of the Cu sources and supported Cu uptake. In pot experiments with Cu deficient soil, foliar applied Cu lignosulphonate with the addition of alkylphenolpolyglycolether, urea and sucrose was the most efficient Cu source. Splitting of the total Cu amount into two doses applied in intervals of 24 hours was the most effective treatment. In this case, grain yield was 90% of that obtained in the same soil with adequate Cu supply. 相似文献