The Potential Use of Organically Grown Dye Plants in the Organic Textile Industry: Experiences and Results on Cultivation and Yields of Dyers Chamomile (Anthemis tinctoria L.), Dyers Knotweed (Polygonum tinctorium Ait.) and Weld (Reseda luteola L.)

The organic cultivation of dye plants for the certified natural textiles industry is an emerging and promising sector of organic farming. In 1999 a field trial was done with different provenances of Dyer’s Chamomile (Anthemis tinctoria L.), Dyer’s Knotweed Polygonum tinctorium Ait.), and Weld (Reseda luteola L.) on two organic farms in Lower Austria. Yields, dyestuff content, and quality parameters were analyzed. Dry matter yields of Weld ranged between 0.7 and 2.7 t ha-1, of Dyer’s Chamomile (flower heads) between 1.1 and 1.8 t ha-1. Significant differences were found between seed Weld provenances as well as between those of Dyer’s Chamomile. The total leaf dry matter of Dyer’s Knotweed (2 cuts) ranged at both sites on average 3.1 t ha-1. Seed provenances did not show differences. The total flavonoid content of Weld ranged between 1.53 and 4.00%, of Dyer’s Chamomile between 0.84 and 1.5%. The content of indican in Dyer’s Knotweed ranged between 0.50 and 1.45% of leaf dry matter, the calculated theoretical content of indigo ranged between 0.22 and 0.64% of leaf dry matter. The general use fastness properties differ according to species and provenance. Both high and low values were achieved. The data on the cultivation of dye plants in organic farming show promising results. Research should address improvement in yields and quality, development of dyestuff extracts, and optimization of dyeing methods. Research on dye plants needs a systemic look at the whole chain including producers, processors, trade, and consumers

Dry matter and fibre yields, and the fibre characteristics of five nettle clones (Urtica dioica L.) organically grown in Austria for potential textile use

The aim of the field trial was to quantifiy yield, fibre content and fibre quality of 5 fibre nettle clones cultivated according to the principles of organic farming. The field trial started in 1997 and was organized in a randomised block design with 4 replications per clone. The field trial was situated in Neulengbach, Lower Austria. Since fibre nettle does not provide sufficient yields in the first cultivation year, the harvest of the second and third cultivation year (1998 respectively 1999) was used for calculation of yield per hectar and for the analysis of fibre content and quality. The dry matter yield (stalks) of the 5 nettle clones in the second cultivation year (1998) lies between 2,3 – 4,7 t/ha. Clone 1 and Clone 7 achieve the highest yields. This result was statistically significant. The dry matter yields of that year correspond with the dry matter yield achieved under extensive cultivation conditions (without nitrogen fertilizer) as described by SCHMIDKE ET AL. (1998). The dry matter yields of the third cultivation year (5,6 – 9,7 t/ha), however, are more than twice as high as those of the second cultivation year. They are also higher than the yields from the nitrogen intensive cultivation system described by VETTER ET AL. (1996) with 200 kg N/ha + 100 kg N/ha after the first cutting (per year; the fertilizer used was calcium ammonium nitrate). This large increase in yield in the third cultivation year is caused by an increase in the height (20 – 40 cm higher) and by the production of runners: the number of stalks per plot more than doubled in the third cultivation year. Additionally the undersowing of clover (Trifolium repens) seems to have had a positive effect on the growing of fibre nettle. The fibre yields lie between 335 – 411 kg/ha in the second cultivation year and between 743 – 1.016 kg/ha in the third cultivation year. Clones with a high dry matter yield have a low fibre content and vice versa. Therefore the differences between the clones in dry matter yield/ha and fibre content are balanced and there is no more difference between the fibre yield/ha of the clones. The fibre content after chemical processing lies in both the second and the third cultivation year between 8 – 16 % drymatter (stalks). This result confirms the maximum fibre contents reported in recent literature (DREYER ET AL. 1996, DREYER & DREYLING 1997, SCHMIDTKE ET AL. 1998, KÖHLER ET AL. 1999, FRANCKEN-WELZ ET AL. 1999). Clone 8 and Clone 9 have the highest fibre content in 1998 (16,0 respectively 14,5 %), and Clone 8 (15,7 %) in 1999. There is no significant difference between the fibre quality (fibre strength, elongation, fibre fineness, lenght of fibre) of the five nettle clones. In general the fibre material is very inhomogeneous, which is caused by the differing consistence of the upper and the lower part of the stalk and by fibre processing methods. In principle, nettle fibres are suitable for textile use, however, the further developement of an economic and functional method for processing along with high yields is essential. The results show that higher yields and fibre contents were achieved in the third cultivation year under the described cultivation conditions of organic farming than other authors (BREDEMANN 1959, VETTER ET AL. 1996, DREYER ET AL. 1996, SCHMIDTKE ET AL 1998, FRANCKEN-WELZ ET AL. 1999). The yields of the third cultivation year are higher than the minimum for economic cultivation as defined by DREYER & DREYLING (1997). The cultivation of fibre nettle under the conditions of organic farming in Austria is therefore possible, as long as fibre processing plants and consumer demand exists. There is a need for further research in optimizing cultivation methods in organic farming (undersowing of leguminosae, manuring with slurry, row width, crop rotation) as well as in optimizing fibre processing methods for the quality of raw materials available and taking into account further processing into textiles (e.g. production of a pure yarn or a mixed yarn with cotton). There is also a need for research into possibilities to use fibres from different parts of the nettle plant for different purposes (e.g. textile and industrial uses)

Production and processing of organically grown fiber nettle (Urtica dioica L.) and its potential use in the natural textiles industry: A review

In Europe, the perennial stinging nettle was cultivated during the 19th century until the Second World War and has a long history as a fiber plant. Clone varieties dating back to the early 20th century are still maintained at European research institutions. The fiber content of clones ranges from 1.2 to 16% dry matter, and fiber yields range from 0.14 to 1.28 Mg/ha. Varietal purity of fiber nettle can only be achieved by planting cuttings. The harvesting of fiber starts in the second year of growth and the crop may produce well for several years. Several agronomic practices influence fiber quality, but causal relations are not yet well understood. Various parts of the fiber nettle plant can be used as food, fodder and as raw material for different purposes in cosmetics, medicine, industry and biodynamic agriculture. Organically produced fibers are in demand by the green textile industry and show potential that is economically promising

Stop Co-Annihilation in the Minimal Supersymmetric Standard Model Revisited

We re-examine the stop co-annihilation scenario of the Minimal Supersymmetric Standard Model, wherein a bino-like lightest supersymmetric particle has a thermal relic density set by co-annihilations with a scalar partner of the top quark in the early universe. We concentrate on the case where only the top partner sector is relevant for the cosmology, and other particles are heavy. We discuss the cosmology with focus on low energy parameters and an emphasis on the implications of the measured Higgs boson mass and its properties. We find that the irreducible direct detection signal correlated with this cosmology is generically well below projected experimental sensitivity, and in most cases lies below the neutrino background. A larger, detectable, direct detection rate is possible, but is unrelated to the co-annihilation cosmology. LHC searches for compressed spectra are crucial for probing this scenario

Comparing Hemp Seed Yields (Cannabis sativa L.) of an On-Farm Scientific Field Experiment to an On-Farm Agronomic Evaluation Under Organic Growing Conditions in Lower Austria

Hemp seed yields of the variety Fedora-19 in an on-farm scientific field experiment on small plots and in an on-farm evaluation in 11 hemp fields under practical organic growing conditions in Lower Austria were compared to give a realistic view of the variability of yields. Dry matter seed yields from the on-farm field experiment ranged from 127 to 143 g/m2. Under practical growing conditions, yields ranged from 34 to 151 g/m2 in the sample plots. The reported hemp seed yield after combine harvesting, drying, and cleaning was between 324 kg/ha and 717 kg/ha. The results of the experiment show that harvesting by hand considerably influences yields. Yields of the manual harvest in sample plots indicate a high correlation with yields harvested by the combine harvester (R2 = 0.91). The commercial yield is 71% of the yields recorded in sample plots in the fields. Our data questions the transfer of results and conclusions drawn from the data of scientific field experiments that employ manual harvest to that of practical circumstances, and support the notion of on-farm research

A Matter of Time: Enacting the Exclusion of Onshore Refugee Applicants through the Reform and Acceleration of Refugee Determination Processes

State-based processes for determining refugee claims are crucial sites of inclusion or exclusion for onshore refugee applicants. This paper argues that cultures of disbelief and exclusion towards onshore refugee applicants are increasingly being enacted indirectly, via procedural reforms to Refugee Status Determination (RSD), which limit the ability of applicants to establish and articulate their claims. Focusing on Australia and Canada, this paper tracks the acceleration and truncation of RSD procedures, which first reflect and then frequently achieve the exclusion of onshore applicants. Two sets of reforms in particular have profoundly limited the terms on which applicants may present their claims. In Canada, this occurred as the result of a major overhaul of RSD that took place in December 2012. In Australia, the policy of ‘enhanced screening’ of applicants achieves the immediate screening-out of certain claims from the Australian determination system. Alongside analysing these reforms as a means of exclusion, this paper argues that the new procedures most disadvantage applicants making claims on the basis of gender-related persecution

A flow equation approach to periodically driven quantum systems

We present a theoretical method to generate a highly accurate {\em time-independent} Hamiltonian governing the finite-time behavior of a time-periodic system. The method exploits infinitesimal unitary transformation steps, from which renormalization group-like flow equations are derived to produce the effective Hamiltonian. Our tractable method has a range of validity reaching into frequency regimes that are usually inaccessible via high frequency $\omega$ expansions in the parameter $h/\omega$, where $h$ is the upper limit for the strength of local interactions. We demonstrate our approach on both interacting and non-interacting many-body Hamiltonians where it offers an improvement over the more well-known Magnus expansion and other high frequency expansions. For the interacting models, we compare our approximate results to those found via exact diagonalization. While the approximation generally performs better globally than other high frequency approximations, the improvement is especially pronounced in the regime of lower frequencies and strong external driving. This regime is of special interest because of its proximity to the resonant regime where the effect of a periodic drive is the most dramatic. Our results open a new route towards identifying novel non-equilibrium regimes and behaviors in driven quantum many-particle systems.Comment: 25 pages, 14 figure