1,917 research outputs found
Development of an Organic Table Grape Production and Market in Switzerland
In Switzerland there is an increasing consumer demand for residue-free, organic table
grapes. The organic cultivation of table grapes, however, is very delicate in humid climates
and experience to advice organic growers is still lacking. The goal of our project that has
started in 2004 is to develop and establish a cultivation system for organic table grapes
under Swiss climatic and economic conditions with a high yield security and fulfilling the
high quality demands of the market. Preliminary results: Interesting cultivars to produce
are e.g. Fanny, Lilla, Palatina. However they are disease susceptible and must be
produced under a rain roof. Better suited cultivars still need to be found. Consumer
acceptance for organic table grapes produced in Switzerland is very positive. However
changes towards new cultivars and lower production costs are necessary. Spray programs
to achieve sufficient disease protection and no spray blotch seem to be realizable, mainly
for production under rain roof
Understory influence on leafroller pupunations in Hawke's bay organic apple orchard
Leafrollers (Tortricidae) were collected from apple foliage and understorey vegetation in six commercial organic apple orchards in Hawke’s Bay over one season. Assessments were made of plant species present in the understorey at the time of collection. All leafroller larvae were reared to adults on artificial diet to identify leafroller species and parasitoids. Nearly half (47%) of all leafrollers collected in these orchards were located in the understorey, highlighting the importance of understorey and its management for the control of leafroller. Dock, clover and dandeliontype plants contributed 25% to the overall understorey, yet hosted 75% of the leafrollers collected from the understorey. Dolichogenidea sp. was the most abundant parasitoid (79%) attacking leafrollers found amongst the apple foliage, whereas Glyptapanteles demeter was dominant in the understorey (61%). Generally the number of leafrollers in an orchard was proportional to the abundance of broadleaf weeds and inversely proportional to parasitis
Klassifizierung unbekannter Proben ökologischer und konventioneller Herkunft mittels FAS anhand von Trainingsdaten aus dem Vorjahr
Different sorts of apples coming from pairs of organic/conv. producers of different locations in Switzerland and Germany were retrospectively investigated in 2004 and prospectively classified in 2005 based on data measured by fluorescence-excitation-spectroscopy (FES) and subsequent discriminant analysis. The result was in 8 of 9 cases a correct identification of the method of production. In one case the data showed no difference
Spatiotemporal Infrared Measurement of Interface Temperatures During Water Droplet Evaporation on a Nonwetting Substrate
High-fidelity experimental characterization of sessile droplet evaporation is required to understand the interdependent physical mechanisms that drive the evaporation. In particular, cooling of the interface due to release of the latent heat of evaporation, which is not accounted for in simplified vapor-diffusion-based models of droplet evaporation, may significantly suppress the evaporation rate on nonwetting substrates, which support tall droplet shapes. This suppression is counteracted by convective mass transfer from the droplet to the air. While prior numerical modeling studies have identified the importance of these mechanisms, there is no direct experimental evidence of their influence on the interfacial temperature distribution. Infrared thermography is used here to simultaneously measure the droplet volume, contact angle, and spatially resolved interface temperatures for water droplets on a nonwetting substrate. The technique is calibrated and validated to quantify the temperature measurement accuracy; a correction is employed to account for reflections from the surroundings when imaging the evaporating droplets. Spatiotemporally resolved interface temperature data, obtained via infrared thermography measurements, allow for an improved prediction of the evaporation rate and can be utilized to monitor temperature-controlled processes in droplets for various lab-on-a-chip applications
Rotwein unter Hochspannung: Mehrjährige Qualitäts- Untersuchung mit Gas-Discharge-Visualisation (GDV)
We investigated whether we can detect any differences in red wines produced either
by bio-dynamic or by standard organic agriculture. We used standard methods to
investigate the quality of the wines and Gas-Discharge-Visualisation (GDV) method to
investigate a holistic quality of the wines. With the GDV-method, samples are exposed
to high voltage. The halo-like gas discharge caused by a burst of electron emission of
the sample is captured by a digital camera underneath a transparent, dielectric surface.
The wine samples measured originate from an On-Farm experiment in South of
France with two separately managed but neighbouring blocks (same soil and climate
conditions): bio-organic and bio-dynamic. Apart from the use of bio-dynamic preparations,
plant protection and fertilization was the same in both blocks. The vinification of
the sampled grapes was made in two replicates which were analysed separately.
During the three years of examination, the bio-dynamic samples did not reveal significant
differences when assessed with standard methods (sensory triangle test, polyphenol
analysis etc.). However, with GDV measurements the values for the imageparameter
“mean intensity” were mostly higher for the wines from bio-dynamically
produced grapes. In a „mixed effect model“ (GDV-parameter „mean intensity“ as
dependent variable, replication und cultivation-system as fix and year as random
effect) the difference was statistically significant. We conclude that the GDV-method
has an interesting potential to detect very sensitively differences in food attributes.
However, in order to interpret the results in terms of consumer-relevant quality further
research is needed
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