Organic rapeseed production in Finland

Most of the 56 organic rapeseed growers interviewed in this research acknowledged modest success in rapeseed yield (often under 500 kg/ha, on average about 800-900 kg/ha), but kept continuing cultivation because of other benefits such as good price and well functioning markets of the product, flexibility in sowing time, possibility to cultivate a temporary fallow to fight the weeds, and need for protein rich fodder for own or neighbor livestock. The main complications in rapeseed cultivation were unfavorable weather conditions, pests and insufficient nutrient levels for optimal yields. The farmers followed carefully the instructions from research and advisory institutions, but were also innovative in developing their own solutions to problems. Because of different conditions with neighboring farms, different soil types and climatic conditions, different sources of fertilizers and availability of pollinators, tailor-made solutions for every farm individually are imperative. Despite problems most farmers were optimistic and were readily investing in the future e.g. by renting and buying more field area for cultivation. Success in organic rapeseed cultivation seems to coincide with optimism, good relationships with family members and neighbors, availability of affordable fertilizers and relatively large cultivation area for efficient crop rotation

Clover rot (Sclerotinia trifolium) and Fusarium fungi in organic red clover in Finland

Sclerotinia trifolium is economically one of the most important pathogens of red clover in Europe and North America, while many Fusarium species can cause root rot in red clover in certain environmental conditions. During the years 2003-2004 S. trifolium was found only in the Northern and Eastern part of Finland, although in 1960's it was common everywhere in Finland

Molecular coupling of light with plasmonic waveguides

We use molecules to couple light into and out of microscale plasmonic waveguides. Energy transfer, mediated by surface plasmons, from donor molecules to acceptor molecules over ten micrometer distances is demonstrated. Also surface plasmon coupled emission from the donor molecules is observed at similar distances away from the excitation spot. The lithographic fabrication method we use for positioning the dye molecules allows scaling to nanometer dimensions. The use of molecules as couplers between far-field and near-field light offers the advantages that no special excitation geometry is needed, any light source can be used to excite plasmons and the excitation can be localized below the diffraction limit. Moreover, the use of molecules has the potential for integration with molecular electronics and for the use of molecular self-assembly in fabrication. Our results constitute a proof-of-principle demonstration of a plasmonic waveguide where signal in- and outcoupling is done by molecules.Comment: 9 pages, 5 figure

Control of potato late blight by caraway oil in organic farming

Caraway (Carum carvi) seeds contain biologically active essential oils, which have shown potential in controlling Phytophthora infestans (P.i.). An attempt is being made to develop a P.i. control strategy for organic farming based on caraway oil

Raman Enhancement in Bowtie-Shaped Aperture-Particle Hybrid Nanostructures Fabricated with DNA-Assisted Lithography

We report on efficient surface-enhanced Raman spectroscopy (SERS) supporting substrates, which are based on DNA-assisted lithography (DALI) and a layered configuration of materials. In detail, we used nanoscopic DNA origami bowtie templates to form hybrid nanostructures consisting of aligned silver bowtie-shaped particles and apertures of similar shape in a silver film. We hypothesized that this particular geometry could facilitate a four-fold advantage in Raman enhancement compared to common particle-based SERS substrates, and further, we verified these hypotheses experimentally and by finite difference time domain simulations. In summary, our DALI-fabricated hybrid structures suppress the background emission, allow emission predominantly from the areas of high field enhancement, and support additional resonances associated with the nanoscopic apertures. Finally, these nanoapertures also enhance the fields associated with the resonances of the underlying bowtie particles. The versatility and parallel nature of our DNA origami-based nanofabrication scheme and all of the above-mentioned features of the hybrid structures therefore make our optically resonant substrates attractive for various SERS-based applications.Comment: 7 pages, 4 figures, Supporting Information (5 pages, 3 tables, 1 figure