Ernährung sichern mit Mischkulturen

Um die Ernährung zu sichern braucht es neue Anbauformen. Dafür eignet sich der Mischanbau, denn er bietet ökologische und ökonomische Vorteile. Das FiBL optimiert durch Züchtung und Anbautechnik den Mischanbau im europaweiten Projekt ReMix

Food security through mixed cropping

We need new farming systems to ensure food security. Intercropping promises to deliver environmental and economic benefits. In the European project ReMIX, FiBL is optimising mixed cropping systems through novel breeding and cultivation approaches

FDZ Annual Report 2008

"Following the exceedingly positive response to our Annual Report 2007, you now have the Annual Report 2008 of the Research Data Centre (FDZ) of the Federal Employment Agency at the Institute for Employment Research in this FDZ Methodenreport. Like last year, the FDZ Annual Report 2008 is not a glossy brochure full of photos but summarises the main events of the past 12 months in a few pages. The Annual Report 2008 is mainly based on key figures which the FDZ made available to the German Council for Social and Economic Data for their evaluation in 2009. The Annual Report also serves to provide transparency for our users, who after all justify the existence of the FDZ. The Report is divided into the following chapters: 'General function', 'Basic information', 'The service-oriented FDZ', 'The international FDZ' and, as an apt conclusion, 'Research at the FDZ'." (Author's abstract, IAB-Doku) ((en)) Additional Information Here you can find the German version of the report.Forschungsdatenzentrum - Bericht, Bundesagentur für Arbeit, IAB, amtliche Statistik, Datenzugang, Datenschutz, Arbeitsmarkt- und Berufsforschung, IAB-Beschäftigtenstichprobe, IAB-Betriebspanel, IAB-Betriebs-Historik-Panel, IAB-Linked-Employer-Employee-Datensatz, Integrierte Erwerbsbiografien, Datenaufbereitung, Datenausgabe, BA-Beschäftigtenpanel, Befragung, IAB-Querschnittsbefragung, IAB-Haushaltspanel, IAB-kombinierte Firmendaten, IAB-Weiterbildungspanel

Helical-edge transport near ν = 0 of monolayer graphene

The complex nature of filling factor ν = 0 of monolayer graphene is studied in magnetotransport experiments. As a function of perpendicular magnetic field a metal-insulator transition is observed, which is attributed to disorder-induced Landau level broadening in the canted antiferromagnetic phase. In the metallic regime a separation of the zeroth Landau level appears and signs of the quantum spin Hall effect are seen near ν = 0. In addition to local transport, nonlocal transport experiments show results being consistent with helical edge transport

New breeding strategies for mixed cropping in a barley (H. vulgare L.) pea (P. sativum L.) model system

Crop mixtures consisting of cereals and legumes have proven as a well-adapted arrangement due to their complementarity towards important resources, especially nitrogen. Crop mixtures combine high yield performance and yield stability. They can contribute to a diversified cropping landscape and adaptation to climate change. The search for alternatives to protein imports from overseas and investments in post-harvest separation technologies are currently fostering their adoption by farmers in Western-Europe, especially under organic and lowinput farming conditions. However, screening and breeding for mixed cropping has hardly been explored for arable crops. Thus, the objective was to develop novel breeding strategies and tools specifically for mixed cropping systems. We tested mixtures and pure stands of a morphologically diverse panel of 32 spring pea (Pisum sativum L.) and eight spring barley (Hordeum vulgare L.) cultivars in replicated field trials at two locations in Switzerland over two years with pea as the focal species. In an incomplete factorial design (Fig. 1) we determined general and specific mixing ability (GMA and SMA, respectively) of pea and barley in analogy to GCA and SCA (general and specific combining ability) in hybrid breeding. Key traits, such as early vigour, canopy height and leaf morphology parameters were measured, due to their potential use as covariates or indirect selection criteria for mixing ability. Our results show that total yield of mixtures can only partly be explained by pea pure stand yields (R² = 0.35), making the latter a weak predictor for mixture yield. Pea GMA variance was predominant over SMA variance which underlines the potential for breeding for mixing ability using a tester. Key traits, such as pea stipule area were correlated (R² = 0.56) with total mixture yield and merit further investigation as indirect selection criteria. The separated yield fractions of pea and barley in mixtures allow to decompose GMA of pea into the producer effect of pea cultivar on pea fraction yield and the associate effect of pea on barley fraction yield. This novel concept allows to elucidate key trait effects on fraction yields of pea and barley which might otherwise be masked when solely using a GMA approach

Development of genetic models to breed for mixed cropping systems

Introduction Mixed cropping, i.e. mixing different crops in the same field, provides agronomic advantages as increased productivity under low inputs conditions (e.g. for organic farming: Bedoussac et al. 2015) and higher yield stability (Raseduzzaman and Jensen 2017). In mixed cropping, choosing the right cultivars is critical for the performance of the mixture, as shown for pea-barley mixtures (Hauggaard-Nielsen and Jensen 2001) and maize-bean mixtures (Hoppe 2016). As performance in pure stand can strongly diverge from performance in mixture, estimating the ability of a cultivar to be mixed with another crop is therefore of utmost importance. For this purpose, concepts of General and Specific Combining Ability in hybrid breeding (Griffing 1956) have been adapted to cultivar and crop mixtures. Thus, these effects are called General Mixing Ability (GMA) and Specific Mixing Ability (SMA) (Federer 1993). In contrast to intraspecific mixtures, interspecific mixed cropping experiments often provide additional information, since harvested lots can be separated into their different grain fractions. Until now, statistical developments mobilizing the additional information provided by separated harvest lots to estimate mixing abilities in intercropping experiments have been neglected. The concept of Producer- and Associate-effects (abbreviated Pr and As, respectively) describes interactions between varieties sown in alternate row trials (Forst 2018). The producer effect Pr is the average performance of a cultivar grown in mixture with other crop-species, whereas the associate effect As is the average effect of a cultivar on the performance of the mixing partner. We used the fraction yields of a spring-pea (Pisum sativum L.) and spring-barley (Hordeum vulgare L.) mixed cropping experiment to determine Pr and As effects of different pea genotypes. The additional information provided by this approach is biologically more informative than GMA/SMA estimates, since it better reflects competition and facilitation occurring between different cultivars of the two crop-species

Die Erbsensorte entscheidet über den Erfolg der Mischung

Sommer-Eiweisserbsen und zweizeilige Gerste sind gute Mischungspartner. Doch gewisse Sortenkombinationen sind besser als andere. Das hat das FiBL in einem zweijährigen Versuch gezeigt

A Solid-State Source of Single and Entangled Photons at Diamond SiV-Center Transitions Operating at 80K

Large-scale quantum networks require the implementation of long-lived quantum memories as stationary nodes interacting with qubits of light. Epitaxially grown quantum dots hold great potential for the on-demand generation of single and entangled photons with high purity and indistinguishability. Coupling these emitters to memories with long coherence times enables the development of hybrid nanophotonic devices that incorporate the advantages of both systems. Here we report the first GaAs/AlGaAs quantum dots grown by the droplet etching and nanohole infilling method, emitting single photons with a narrow wavelength distribution (736.2 ± 1.7 nm) close to the zero-phonon line of silicon-vacancy centers. Polarization entangled photons are generated via the biexciton-exciton cascade with a fidelity of (0.73 ± 0.09). High single photon purity is maintained from 4 K (g(2)(0) = 0.07 ± 0.02) up to 80 K (g(2)(0) = 0.11 ± 0.01), therefore making this hybrid system technologically attractive for real-world quantum photonic applications

Single photon emission from ODT passivated near-surface GaAs quantum dots

Epitaxially grown semiconductor quantum dots are promising candidates for pure single photon and polarization-entangled photon pair emission. Excellent optical properties can typically be ensured only if these so-called “artificial atoms” are buried deep inside the semiconductor host material. Quantum dots grown close to the surface are prone to charge carrier fluctuations and trap states on the surface, degrading the brightness, coherence, and stability of the emission. We report on high-purity single photon emission [g(2)(0) = 0.016 ± 0.015] of GaAs/AlGaAs quantum dots that were grown only 20 nm below the surface. Chemical surface passivation with sulfur compounds such as octadecanethiol has been performed on quantum dots with 20, 40, and 98 nm from the surface. The reduction of the density and influence of surface states causes improvements in linewidth and photoluminescence intensity as well as a well-preserved single photon emission. Therefore, the realization of hybrid nanophotonic devices, comprising near-field coupling and high-quality optical properties, comes into reach