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1.
Background: Nitrogen losses is an economic problem for wheat production and a high risk to the environment. Therefore, improved N fertilizer management is a key to increasing the N efficiency and minimizing N losses. To increase N efficiency, enhanced fertilizers such as urea combined with urease inhibitor can be used. Aims: The aim of present study was to evaluate the effects of different N forms on grain storage protein subunits in winter wheat and to examine whether the observed changes correlate with parameters of baking quality. Methods: The investigation was performed over two consecutive years at two locations in Germany. Protein subunits were analyzed by SDS‐PAGE. Results: Protein concentrations were similarly increased after fertilization with ammonium nitrate and urea + urease inhibitor. Analysis of the individual storage protein fractions indicated that both fertilizers specifically enhanced ω‐gliadins and HMW glutenins, but the effect was more pronounced in the ammonium nitrate treatment. Application of urea + urease inhibitor had greater influence on the protein composition and resulted in higher specific baking volume as well as the best fresh keeping ability, in comparison with urea treatment. Conclusion: Considering that the urea + urease inhibitor treatment resulted in almost comparable improvements of NUE and baking quality, with the additional benefit of reduced N losses in combination with easy handling, urea + urease inhibitor can be recommended as a viable alternative to both urea alone and ammonium nitrate treatments. This opens up an opportunity for the reduction of N loss in wheat production when use of urea is preferred.  相似文献   
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Journal of Plant Diseases and Protection - This study explores the food plant spectrum of the sugar beet weevil (Asproparthenis punctiventris Germar; Coleoptera: Curculionidae), one of the most...  相似文献   
4.
Effect of low SO2-concentrations on the activities of some glycosidases in the foliage of clonal forest trees. The aim was to find an early indicator of latent SO2 injuries in a beech and a spruce clone. After exposure to 0.0, 0.05, 0.1 and 0.2 ppm for several weeks in outdoor fumigation chambers, the activities of β-glucosidase in the beech and β-galactosidase in the spruce clone and β-l,3-glucanase in both species were significantly raised. As the beech clone was very sensitive to SO2, an indication of latent injury could be ascertained only in the 0.05 ppm treatment where the rise of the β-glucosidase activity appeared some days before necroses. Contrary to beech, the spruce clone was tolerant to all SO2-treatments and the enzymatical changes could be used as early indicators of latent injuries.  相似文献   
5.
Interactions between soil humic substances and metal ions I. Isolation and characterization of the soil humic substances From two horizons of a podzol humic acids and fulvic acids were isolated by two different methods. The obtained samples were characterized by elemental analysis, the determination of the ash and moisture content, functional group analysis as well as FTIR-, 1H-NMR-, and 13C-NMR-spectroscopic examinations. In spite of the different isolation methods humic and fulvic acids show great similarities. A higher oxidized state and a lower content of aromatic structural features are clearly observed in the fulvic acids in contrast to humic acids. Besides aromatic structural elements, distinct aliphatic sections were detected in the investigated samples, which showed a lower concentration in the less transformed fractions of the Ahe-horizon.  相似文献   
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Natural and anthropogenic components of soil acidification   总被引:2,自引:0,他引:2  
The following 8 theses are theoretically founded and experimentally quantified. 1. Rocks contain only bases and no acid precursors. Therefore, with the exception of sulfide containing rocks, soils cannot acidify as a result of atmospheric rock weathering. 2. A consumption of protons in rocks and soils results in a decrease of their acid neutralizing capacity (ANC) and can result in the buildup of a base neutralizing capacity (BNC). Strong soil acidification leads to the formation of stronger acids from weaker acids in the solid phase; this may be connected with a decrease in the BNC. 3. Weak acids (carbonic acid) lead in geological times to the depletion of bases without a larger accumulation of labile cation acids. Strong acids (HNO3, organic acids, H2SO4) can lead within a few decades to soil acidification, i.e. to leaching of nutrient cations and the accumulation of labile cation acids. 4. The acid input caused by the natural emission of SO2 and NOx can be buffered by silicate weathering even in soils low in silicates. 5. The cause of soil impoverishment and soil acidification is a decoupling of the ion cycle in the ecosystem. 6. Acid deposition in forest ecosystems which persists over decades leads to soil acidification. 7. Formation and deposition of strong acids with conservative anions (SO4, NO3) shifts soil chemistry into the Al or Al/Fe buffer range up to great soil depth. In such soils eluvial conditions prevail throughout the solum and even in upper part of the C horizon: in connection with the decomposition of clay minerals, Al and eventually Fe are being eluviated. The present soil classification does not include this soil forming process. 8. In the long run, soil acidification by acid deposition results in the retraction of the root system of acid tolerant tree species from the mineral soil, and in water acidification.  相似文献   
7.
Chemical properties of forest soils in the pleistocene of Northwest Germany and their classification based on soil buffering systems In order to characterize the chemical characteristics of forest soils of Hamburg, 800 soil samples and 400 root samples from 172 sites were used to obtain suitable soil chemical and ecochemical parameters. A strong and deep reaching soil acidification was observed on all sites with exception of those on till. The sulfate concentration in the equilibrium soil solution allows the conclusion that deposition of acid plays a significant role in this acidification. Classification of sites based on edaphic factors did not provide useful information on the chemical status of soils. However, grouping of soil horizons using pH measured in 0.01 M CaCl2 lead to a stratification according to the soil buffering systems. Distinction between the exchanger and the aluminium buffer ranges was, however, not quite satisfactory.  相似文献   
8.
Interaction between soil humic substances and metal ions. II. Investigation of soil humic substances by gel permeation chromatography and vapour pressure osmometry By gel permeation chromatography and vapour pressure osmometry average molar masses of soil fulvic and soil humic acids from two horizons of a podzol were determined. For the fulvic acids average molar masses of 9000 g/mol were obtained by the chromatographic method, while 5000 g/mol were obtained by the osmometric method. In contrast to these results for the humic acids values were measured which are 3 - 4 times larger when measured by gel permeation chromatography and 2 - 3 times smaller when measured by vapour pressure osmometry. The average molar masses found show that the applied methods of isolation and purification as well as the different determination methods with the experimental conditions attached to them have a considerable influence on the molecular size of the isolated humic substances.  相似文献   
9.
Classification of thermally modified wood by FT-NIR spectroscopy and SIMCA   总被引:1,自引:0,他引:1  
Quality assessment of thermally modified wood has evolved as one of the major fields in the research on thermal modification of wood. This study investigates NIR spectroscopy in combination with the pattern recognition method of soft independent modeling of class analogies (SIMCA). Focus is put on identifying different treatment intensities of thermally modified samples of beech, ash, and Norway spruce. The results indicate that SIMCA classification based on NIR spectroscopy could be used for quality control of thermally modified wood. The method might be applicable for producers (pre-delivery checks) and customers (reception control). However, transfer from laboratory to industrial conditions needs further investigation.  相似文献   
10.
To tackle global challenges such as food supply and renewable energy provision, the improvement of efficiency and productivity in agriculture is of high importance. Site-specific information about crop height plays an important role in reaching these goals. Crop height can be derived with a variety of approaches including the analysis of three-dimensional (3D) geodata. Crop height values derived from 3D geodata of maize (1.88 and 2.35 m average height) captured with a low-cost 3D camera were examined. Data were collected with a unique measurement setup including the mobile mounting of the 3D camera, and data acquisition under field conditions including wind and sunlight. Furthermore, the data were located in a global co-ordinate system with a straightforward approach, which can strongly reduce computational efforts and which can subsequently support near real-time data processing in the field. Based upon a comparison between crop height values derived from 3D geodata captured with the low-cost approach, and high-end terrestrial laser scanning reference data, minimum RMS and standard deviation values of 0.13 m (6.91% of average crop height), and maximum R2 values of 0.79 were achieved. It can be concluded that the crop height measurements derived from data captured with the introduced setup can provide valuable input for tasks such as biomass estimation. Overall, the setup is considered to be a valuable extension for agricultural machines which will provide complementary crop height measurements for various agricultural applications.  相似文献   
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