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Silage maize (Zea mays L.) is grown over a large area and is closely associated with cropping systems that lack diversity with relatively high impacts on soil quality and nature. Mixed or intercropping can reduce the risk of erosion, increase crop biodiversity, and improve nitrogen utilisation. The combination of maize and runner bean (Phaseolus vulgaris var. vulgaris), which originated in Latin America, has this potential and has been the subject of more intensive research in Germany and Switzerland for several years. Runner bean is closely related to common bean. It has a climbing stem.

Intercropping of legumes and cereals is an important management method for improving yield stability, especially in organic farming systems. However, knowledge is restricted on the relevance of different nutrient transfer pathways. The objective of the study was to quantify nitrogen (N) and carbon (C) transfer from peas to triticale by (1) direct root contact (= R), (2) arbuscular mycorrhizal fungi (AMF; = A), and (3) diffusion (= D). Pea (Pisum sativum cv. Frisson and P2) and triticale (Triticum × Secale cv. Benetto) plants as intercrop were grown for 105 days. Treatment ADR enabled all transfer paths between the two crops. Treatment AD with root exclusion enabled AMF and diffusion transfer between peas and triticale. Treatment A with a diffusion gap barrier only allowed AMF transfer. Pea plants were labelled every 14 days with a 13C glucose and 15N urea solution, using the cotton wick technique. Direct root contact resulted in the highest pea rhizodeposition and thus the largest absolute amounts of N and C transfer to triticale. Root exclusion generally changed composition of rhizodeposits from fine root residues towards root exudates. Pea plant-N consisted of 17% N derived from rhizodeposition (NdfR) in treatment ADR but only 8% in the treatments AD and A, independently of pea variety, whereas pea plant-C consisted of 13% C derived from rhizodeposition (CdfR), without pea variety and transfer path treatment effects. Averaging all transfer path treatments, 6.7% of NdfR and 2.7% of CdfR was transferred from Frisson and P2 to triticale plants. Approximately 90% of this NdfR was transferred by direct root contact from Frisson to triticale and only 10% by AMF, whereas only 55% of CdfR was transferred to triticale by direct root contact, 40% by AMF and 5% by diffusion. Similar percentages were transferred from mutant P2 to triticale. Root exclusion generally changed RD composition from fine root residues towards root exudates.

Preparing quantum states is essential for quantum information processing since any process must start at a well-defined initial state. State conversion describes techniques to transform a specific initial- into a predefined target state. This dissertation investigates quantum state conversion for two interacting qubits and its specialization to a constrained system where only adjacent levels are connected. Furthermore, it shows its applicability in a system of three qubits supposed to model interacting Rydberg atoms. A general Lie-algebraic approach is discussed, allowing a wide range of unitary transformations of the interacting two-qubit system to be described by two independent pseudospin degrees of freedom. Although restricting the representable transformations, the approach offers a simple description of many different conversion schemes and is well-suited to discuss the mentioned constrained situation. For this constrained Hamiltonian, a specific state conversion scheme is developed, which can be adopted in a reduced system of three qubits. These three qubits are supposed to model a Rydberg-atom trimer, and the developed conversion scheme maps onto the transformation between the three-atomic W state and the corresponding Greenberger-Horne-Zeilinger state. This mapping is achieved by reducing the eight-dimensional system to an effective four-level system. Two possible reduction schemes are presented. One depends on phase-matching conditions and the other on lifting degeneracies and employing multiple separated time scales in the eight-dimensional dynamics. The control over the atomic ensemble is established via the interaction with coherent states of the electromagnetic field. All topics are presented in the framework of quantum optics which is the theoretical foundation of much of the developing field of quantum technologies. The presented research shows how to design quantum state conversion protocols for two interacting qubits and apply such conversion protocols to more complex systems by employing reduction schemes. These reduction schemes allow for an effective description by lowering the dimension of the considered dynamics. The presented W to Greenberger-Horne-Zeilinger state conversion protocol in the Rydbergtrimer model outperforms previously proposed solutions for the same task.

Journal für Kulturpflanzen 68(6) 2016, Grain legumes are important crops required for protein-rich animal fodder. The aim of this study was to (i) examine the suitability of grain legume cropping systems for cultivation as protein-rich fodder, (ii) compare the performance of winter and spring types of faba beans and peas, as well as to compare the performance of peas sown in pure stand and in mixture with cereals, and (iii) determine the impact of previous legume crop on succeeding wheat under less favorable soil conditions in organic agriculture. In a field trial on a commercial farm in Luxembourg, eight grain legume cropping systems (as given under ii plus soybean and blue lupin) and a non-nitrogen fixing control crop (triticale) were cultivated followed by wheat in two consecutive seasons, employing a randomized complete block design with four replicates. All cropping systems except for winter pea in pure stand, were suitable for cultivation as protein-rich fodder even under less favourable soil conditions. Given sufficient soil moisture, faba beans constituted the best choice (protein yield: 961-1193 kg ha-1). Semi-leafless peas reached a significantly better yield when sown in pure stand (p ≤ 0.05; 3539-4154 kg ha-1) compared with the mixture (2920-3852 kg ha-1), whereas full-leaf types should be cultivated with a cereal partner. Winter vs. spring faba beans did not perform significantly different while for peas, the spring form performed best, likely again depending on leaf type rather than sowing time. The lower previous crop value of mono-cropped cereals (yield first experimental sequence: 2056 kg ha-1) compared with cereals in mixture with grain legumes was confirmed, with best performance of wheat succeeding spring pea in pure stand (first experimental sequence, yield: 3661 kg ha-1). Grain legumes in pure stand exhibited a higher previous crop value than winter triticale or grain legumes grown in mixture. In conclusion, grain legumes were promising candidates for generating protein-rich feeding stuffs, even under less favorable soil conditions in organic agriculture in Luxembourg.

Field trials on reduced soil tillage under organic farming conditions across Europe were used to compare the soil quality changes over time. Soil organic carbon fractions, soil carbon stocks and microbial community structure were analysed. Most severe differences between plough and reduced tillage were found in the top ten cm of the soil profile. Differences became less or not significant in deeper layers. Analyses are still ongoing and will only be ready to be presented at the conference.

If farmers want to use reduced tillage in organic agriculture, they often face great challenges in weed control. One goal of the European research project TILMAN ORG (www.tilman-org.net) was to develop a more efficient weed management and increased biodiversity through improved use of green manures in different systems of reduced tillage. In a repeated one year trial on the research farm of University of Kassel the effects of different green manure species and different tillage systems on weed cover, density and biomass as well as yield of a subsequent main crop were examined. Sinapis alba, Trifolium resupinatum and Vicia sativa were tested as green manure species. Bare fallow served as control. After the green manures the main crop oat was sown in four different tillage systems: (1) plough, (2) chisel (2011/12) or disc harrow (2012/13), (3) mulching + drilling and (4) direct drilling. In 2011/12, weed cover was generally low in the plough system compared to the other tillage systems. In the mulching + drilling- and direct drilling- systems V. sativa was able to suppress weeds considerably more efficiently than the other green manure treatments. The oat plots after the green manure species S. alba and T. resupinatum as well as the bare fallow had to be given up because weed pressure was too high. Instead, the oat yield in the mulching + drilling- and direct drilling treatments after green manure species V. sativa resulted in oat yields similar to the plough treatments. In the chisel system, oat yield in the V. sativa treatment was significantly higher than in the other green manure treatments. 2012/13 all mulching + drilling- and direct drilling- plots had to be given up because of too high weed pressure. In the disc harrow– system weed pressure differed not significantly from the plough system, but only green manure species V. sativa resulted in comparable oat yields.

Background In recent years soybean (Glycine max L.) has gained significant attention in Europe due to its ability to produce high quality protein for human and animal consumption. Under the climatic conditions prevalent in Central Europe, low temperature is the major factor limiting soybean growth and symbiotic nitrogen fixation.

Three field experiments were conducted during 2002 and 2004 on two sites in Germany in order to examine the impact of preceding crop, pre-sprouting, N- and K-fertilization and cultivar on total tuber fresh yields, tuber DM, glucose and fructose concentration, as well as the colour of crisps and the quality score of French fries at harvest and after storage. Generally, total tuber yields depended very much on the growing season. However, highest yields were obtained when horn grits were applied along with potassium sulphate. Increasing yields after cattle manure fertilization could be attributed to K rather than N. Combined N and K fertilization may cause DM concentration to fall short of the required minimum for crisps. Pre-sprouting and storage increased tuber DM concentration considerably. Cultivars belonging to the very early and early maturity type showed the largest relative increase of reducing sugars due to storage. On the whole, results suggest that the effect of agronomic measures such as fertilization, preceding crop and seed-tuber preparation may be rather small and the response of internal tuber quality and quality of fried products difficult to predict. The quality standards for tuber raw stock can be accomplished best when adequate cultivars suitable for storage are chosen.

Die Ergebnisse zeigen, dass die zufriedenstellende Erträge mit einer je nach Verarbeitungsrichtung geforderten Sortierung durch die Entwicklung von, dem System des Ökologischen Landbaus angepassten pflanzenbaulichen Optimierungsstrategien möglich ist. Hierzu sind standortangepasste Strategien unter Berücksichtigung von Sortenwahl, Vorfruchtwirkung, Beregnung usw. zu erarbeiten.Die erzielten Qualitäten zum Zeitpunkt der Ernte sind für die Verarbeitungsrichtung Pommes frites als gut bis sehr gut zu bezeichnen. Die Qualität der Sorten mit Chipseignung ist insbesondere nach der Lagerung noch nicht zufriedenstellend gewesen. Hierzu können einerseits die durch Phytophthora-Befall nicht ausgereiften Kartoffeln bzw. andererseits die nicht optimalen Lagerungsbedingungen beigetragen haben. Von besonderem Interesse sind daher für den Ökologischen Landbau Sorten mit hoher Phytophthora-Resistenz und frühem Knollenansatz sowie die 4°C-Sorten. Ergänzend sind Strategien für eine Lagerung bei 8°C unter Verzicht auf Keimhemmungsmittel zu entwickeln, um die vorhandenen Sorten mit hohem Ertragsniveau und guten Qualitäten möglichst lange in der Verarbeitung einsetzen zu können.

Eine Ausweitung des Ökologischen Landbaus setzt die Erschließung neuer Absatzmärkte voraus. Bei Kartoffeln bietet sich die Verarbeitung zu Pommes frites oder Chips an. Ausgehend von dem Wissensdefizit über die Verarbeitungseignung von ökologisch erzeugten Kartoffeln wurden Versuche mit ausgewählten Verarbeitungssorten von den Universitäten Kiel und Kassel sowie der BAGKF in Detmold initiiert. Ziel der Untersuchungen war es, ausgewählte Sorten an unterschiedlichen Standorten auf ihre Anbaueignung im Ökologischen Landbau zu prüfen, um erste Anbauempfehlungen und den weiteren Forschungsbedarf ableiten zu können.In den Jahren 2000 und 2001 wurde ein Sortiment von insgesamt 21 Sorten geprüft, wobei jeweils 13 Sorten eine Verarbeitungseignung zu Chips bzw. zu Pommes frites aufwiesen. Die Feldversuche wurden an den 3 ökologisch bewirtschafteten Standorten Wulksfelde (Bioland-Betrieb, lS), Versuchsgut Lindhof (Universität Kiel, sL) und Domäne Frankenhausen (Universität Kassel, Ut3) angelegt. Die Qualitätsprüfung auf die Verarbeitungseignung erfolgte an der BAGKF in Detmold im semitechnischen Maßstab.Im Durchschnitt der zwei Untersuchungsjahre wurde bei den Sorten mit Chips-Eignung ein Ertragsniveau von 304 dt ha-1 erreicht, wobei eine deutliche, in beiden Jahren gleichgerichtete Standortdifferenzierung festzustellen war. Das niedrigste Ertragsniveau mit 221 dt ha-1 wies der Standort Lindhof auf, das höchste der Standort Frankenhausen mit 378 dt ha-1. Von den geprüften Sorten der mittelfrühen Reifegruppe wiesen die Sorten Agria und Marlen, von den geprüften Sorten der späten Reifegruppe die Sorte Sonate die höchsten Erträge auf. Der TM-Gehalt betrug im Durchschnitt 24,8 % und lag somit über dem für die Verarbeitung zu Chips geforderten TM-Gehalt von 22 % Die Qualitätsbeurteilung zeigte deutliche Sortenreaktionen mit Chipsnoten von 4,8 (Delikat) bis 8,1 (Diana) Die besten Qualitäten zeigten im Mittel der 3 Standorte die Sorten Diana, Marlen und Kolibri. Das Ertragsniveau der für die Verarbeitung zu Pommes frites geeigneten Sorten lag im Durchschnitt der Versuche bei 322 dt ha-1. Die höchsten Erträge erzielten die Sorten Agria und Marena; die Sorten Sonate und Beluga lagen ebenfalls über dem Durchschnittsertrag. Die Qualitätsbewertung nach dem „Karlsruher Schema“ zeigte im Vergleich zur Einstufung in der Beschreibenden Sortenliste mit Ausnahme der Sorten Delikat und Nora vergleichbare bzw. bessere Einstufungen als in der Sortenliste ausgewiesen.