Zur Eignung des Kornguts unterschiedlich stickstoffgedüngter Getreidebestände als Rohstoff für die Bioethanolproduktion

The Suitability of Grains from Cereal Crops with Different N Supply for Bioethanol Production
The properties of grains of different small grain cereals, produced under increasing N-supply levels, for conversion into bioerhanol were investigated. Grain material of winterwheat, -rye and -triticale, two cultivars each, was used At two locations, field experiments comprising several N-fertilization levels between 0 and 180 kg N/ha were conducted. The main parameters analysed were the bioethanol output (1 bioethanol/dt grain dry matter) and the bioethanol yield (1 bioethanol/ha), both under addition and without addition of technical enzymes. Furthermore, the falling numbers, the protein content and die autoamylolytic quotient (AAQ) were determined. AAQ means the autoamylolytic bioethanol output related to die output under addition of technical enzymes. With a rising N-supply, yields/ha and die protein contents of grain increased differently. Combined with increasing protein contents, decreasing bioethanol outputs were measured, particularly with wheat, to a smaller extent with triticale, and to an even lesser extent with rye. Only with wheat were die AAQ-values significantly reduced as a consequence of rising N-supply levels. In interaction with growing conditions, cultivars and N-levels, the bioethanol yields/ha of rye and triticale equalled or even surpassed the yields of wheat, particularly under autoamylolytic-conversion processing conditions.     

Kartierung und geostatistische Analyse der Unkrautverteilung in Zuckerrübenschlägen als Grundlage für eine teilschlagspezifische Bekämpfung

Mapping and geostatistical analysis of weed distribution in sugarbeet fields for site-specific weed management
Field experiments were conducted to study the distribution of weeds in 18 sugarbeet fields of 3 ha each. The distance between each sampling point was 7.5–20 m. Weed density was counted and maps were plotted for the distribution of Chenopodium album and Solanum nigrum using linear interpolation. Geostatistical methods were applied to analyse the variance of weed density between the sampling points. A clear detection of weed patches was possible when the variance of weed density at a single sampling point 'nugget effect' was low and a high continuity between neighbouring grid points existed. If soil conditions or cultivation methods are not homogeneous in the field (drift), no continuity between the sampling points was found. Geostatistical analysis of the weed distribution in agricultural fields provide helpful information for a site-specific weed management.     

Automatisierte Unterscheidung von Unkrautarten nach Formparametern mit Hilfe der quantitativen Bildanalyse

Automatic distinction of weed species using form parameters by means of digital image processing
In former investigations the possibility to distinguish weed from soil background by computerized quantitative image analysis has been reported. In the present studies image analysis technique are applied to identify different weed species. From six typical winter weed species including various growth stages, 300 color slides were taken at the research station in Bonn on the 4th of February, 1988. From each slide a number of form parameters were measured automatically out of the digitized shape of each weed plant. Form parameters including area, perimeter, minimum and maximum diameter of the plants are taken from the digitized shape of each weed as well as figures representing the relative proportions of these parameters. For automatic discrimination up to 9 of the parameters were selected to compute five so-called canonical variables. The values of these variables are typical for each weed species and can be interpreted as their "finger prints". The average rate of correct identification was 82.3 %. The scientific and practical implications of the results are discussed.     

Die Wurzelentwicklung von Zuckerrübenpflanzen auf einem Sandlöß-Standort und ihre Bedeutung für die Stickstoffernährung

Root development of sugar beet plants on a sandy loess site with regard to nitrogen nutrition.
Root development of sugar beet plants in a sandy loess soil (Haplic Phaeozem) was observed from the early seedling stage up to harvest by measuring at first the greatest vertical and lateral extension of the root systems of single plants and later the rooting density of the whole plant stands (auger method, profile wall method).
During the seedling stage not only the subsoil, but also large parts of the topsoil between the plants remained unoccupied by the root systems. In this phase the greatest lateral extension of single roots reaches nearly the length of the greatest leaf of the plant. With the closure of the canopy the rooting density in the topsoil accounts to 1–2 cm cm⁻³.
In summer roots penetrate to a depth of 100–150 cm with rooting densities of 0.1 to 1 cm - cm⁻³. Thus, the plants gain not only access to water reserves, but sometimes meet remarkable amounts of nitrate which under the relatively dry conditions of the region tends to accumulate in 60–120 cm depth and – when taken up by the beet plants in the late stage of growth – affects crop quality negatively.     

Multiple Endopeptidasen als biochemische Marker für die Resistenz von Winterweizen gegenüber Pseudocercosporella herpotrichoides (Fron) Deighton

Multiple endopeptidases as biochemical marker for resistance of winter wheat to Pseudocercosporella herpotnchoides (Fron) Deighton. Electrophoretic patterns of primary leaf endopeptidases in breeding material derived from crosses between different winter wheat genotypes and amphidiploids (Triticum turgidum×Aegilops ventricosa) were compared with those of cultivars susceptible to Pseudocercosporella herpotrichoides. The results indicate that the multiple endopeptidase EP-1 coded by Wheat chromosome 7 D is absent in the international known lines ‘VPM 1’ and ‘Roazon’ and in all 24 winter wheat selections with increased resistance to P. herpotrichoides. A close relationship between the absence of EP-1 and the introduction of Aegilops ventricosa resistance is assumed. The use of this biochemical marker in wheat breeding is proposed.     

Dynamisches Entscheidungsmodell zur Lenkung von Unkrautkontrollmaßnahmen in Wintergetreide mit Hilfe digitaler Bildverarbeitung

Dynamic decision model for weed control methods in cereals by means of digital image analysis
Field experiments were conducted to study weed-crop competition in winter wheat, -barley and -rye. Weed cover and crop cover was determined over time by digital image analysis of slides taken in the field. The relation of percentage weed coverage and crop coverage was most suitable to quantify the competition of weed population on the crop. In addition the model "UNPROG" was established to predict yield losses caused by weed competition and to estimate the profitability of chemical or mechanical weed control. The model was tested on 22 farms in Nordrhein-Westfalia in autumn 1991 and spring 1992. In 65 out of 72 field plots (92 %) of winter cereals "UNPROG" gave correct prediction with respect to necessity of weed control.     

Wirkung von Impfung, N-Spät-, PK-Düngung und Beregnung auf den Kornertrag und die N-Akkumulation in den Samen von mehreren Sojabohnensorten an zwei Standorten Deutschlands

Effect of inoculation, late N- and PK-manuring and irrigation on seed yield and N-accumulation in the seed of several varieties of soybean at two locations in Germany
Effect of inoculation with rhizobium, late N- and PK-fertilization and irrigation on yield and N-accumulation in seeds of four soybean cultivars was tested in a polyfactoral experiment design.
Seed yield ranged from 11.5 to 43.7 dt DM/ha and N-accumulation in seeds from 52 to 247 kg/ha. Irrigation and inoculation were the most effective production techniques. Cultivar MA96 yielded 38.0 dt DM/ha in Frankenthal on a sandy soil when plants were irrigated and inoculated. No further yield increase was obtained with additional NPK-fertilization. Cultivar KW269 resulted in a significant higher yield (43.7 dt DM/ha) when late N-fertilization was given to irrigated and inoculated plants.     

Stickstoffdüngung und chemischer Pflanzenschutz in einem Dauerfeldversuch und die Ertragsgesetze von Liebig, L.iebscher, WOLLNY und MITSCHERLICH

Nitrogen fertilization and chemical plant protection in a long-term field experiment and the yield response laws of L iebig , L iebscher , W ollny and M itscherlich
An interpretation of L iebig 's "law of the minimum", L iebscher 's and W ollny 's "law of the optimum" and M itscherlich 's "law of constant activity" for two growth factors is presented. With three-quadrant diagrams (crop yield vs. N fertilization, crop yield vs. N uptake, N uptake vs. N fertilization) a long-term field experiment in Göttingen (Ackerbau-Systemversuch) is analyzed. This experiment started 1981 with the following treatments: 1. crop rotation (a: short rotation, sugar-beet, winter-wheat, winter-barley/vetch-green-manure; b: long rotation, sugar-beet, winter-wheat, winter-barley, lucerne, maize, faba beans); 2. chemical plant protection (a: with; b: without); 3. mineral nitrogen fertilization procedure (a: N-fixed, cumulative effects; b: N-rotating, one year's effects of different N fertilization); 4. mineral nitrogen fertilization (a: nil; b: suboptimal; c: optimal; d: hyper-optimal doses).
Without chemical plant protection resource use efficiency of applied nitrogen decreased according to L iebscher 's and W ollny 's "law of the optimum". In most cases this "law of the optimum" was applicable to the empirical data. L iebig 's "law of the minimum" and M itscherlich 's "law of constant activity" are exceptional cases, whereas L iebscher 's and W ollny 's "law of the optimum" has more general validity. For maximal resource use efficiency the growth factors have to be combined in optimal amounts.