Reseda luteola

Dyer 's rocket ( Reseda luteola )

The dyer 's rocket ( Reseda luteola ), also dyer's mignonette, Real Wau, yellow or Gilbkraut called, is a flowering plant in the family of Resedagewächse ( Resedaceae ). It is native to western Asia and the Mediterranean area and is affecting large parts of Europe as alteingebürgert ( archaeophyte ). It is an old dye plant.

• 5.1 Notes and references

Description

The dyer 's rocket is a deciduous, one-to two -year herbaceous plant that reaches the plant height of 40 to 150 centimeters. The stiff upright stems are branched. The alternate and spirally on the stem, arranged in a basal rosette and the second year in the first year leaves are almost sessile. The undivided, bare leaf blades are linear to lanceolate with all edge which is often wavy.

In stark, racemose inflorescence are many densely flowers together. The inflorescence axis is extended to fruit maturity. The flower stem is at most 2.5 millimeters long. The odorless, hermaphrodite flowers are zygomorphic and cruciform. There are usually four, rarely three, sepals present. The four petals are bright yellow. The upper petal is four to fünfzipfelig, side are dreizipfelig. The flowering period is between June and September.

The inflorescence bears many fruit capsules. Upstanding capsule fruits are spherical with a length of 2 to 4 mm and contain many seeds. The very small seeds are only 0.2 micrograms difficult. Fruit ripening takes place from September to October.

Ecology

The dyer 's rocket is a two-year half- rosette plant, Hemikryptophyt and a deep-rooting.

Ecologically flowers are inconspicuous, gay game " nectar leading disk flowers ". The yellow color of the petals is caused by the flavone luteolin. The flowers are self-fertile and their nectary is covered. Pollinators are mainly smaller wild bees, flies and beetles.

It is fruit capsules with a terminal pore. Already young fruits are open at the top. They are wind - and animal shakers. The tiny seeds have a black Elaiosom that favors dispersal by ants. In addition, people spread occurs. Because of the smallness of the opening of the fruit capsule they are seeds only very gradually spread. The tiny seeds are durable refrigeration and light to germinate.

Occurrence

The dyer 's rocket is native to western Asia and the Mediterranean region. As an ancient dye plant it is affecting large parts of Europe as a cultural relic alteingebürgert ( archaeophyte ). Only in Scandinavia it occurs only sporadically and in Eastern Europe, he is missing. It has been proven since the Neolithic Age as a cultural companion. Maybe it is indigenous in Germany. Even in America, Australia and New Zealand, the dyer 's rocket was introduced.

Dyer 's rocket grows on forest impacts and dry ruderal as roadsides, dumps and debris. He is a pioneer Unprocessed and prefers dry, nutrient-rich sites. The species grows to the montane altitudinal zone.

Use

The dyer 's rocket can be used for dyeing fabrics. Be used while the aboveground plant parts, especially the upper flowering branches are rich in luteolin and apigenin the dyes (2% to 4% dye in the dry matter ). The plant is particularly suitable for dyeing animal fibers such as wool and silk, but also of linen. It was also used for wall paint in living rooms. The seed contains up to 40% oil, which may be processed to varnish.

History

The oldest finds of seeds come from Neolithic pile dwellings on Lake Pfäffiker and Lake Neuchâtel, Lake Zurich. However, it is not clear whether the plants used or were deported only seed to Central Europe. For reliable detection of the use for dyeing remains of leaves or stems or mass exemplary occurrences of seeds would be required. The occurrence of other dye plants in the Iron Age settlement of high village also points to such use. Virgil and Vitruvius described a plant lutum that was used for yellow and green coloring. It is likely that this acted to the dyer 's rocket. From the Middle Ages (12th century) seed finds are known again.

Prior to the discovery of America, the dyer 's rocket was one of Europe's most important yellow dyes, grown mainly in England, France and Germany, especially in Thuringia and the region around Halle. Plants from northern latitudes had lower color effect. 1927 dyer 's rocket was only used for dyeing silk. As part of the increased interest in dye plants in places of cultivation was resumed, including in Germany, here in Thuringia and Brandenburg, and in Turkey.

Cultivation and income

Dyer 's rocket requires loose limestone soils and plenty of sun. Negative on the dye content is high nitrogen concentrations can occur. The seeds are sown in late summer or very early spring, when young, a mechanical weed control ( mechanical hoe ) is usually necessary, herbicides are not approved for dyer 's rocket. The harvest is about 14 days after flowering, followed by a rapid drying at 40 to 60 ° C. The yield is 40-45 quintals of dry matter per hectare, the dye yield is 60 to 100 kg per hectare.

Pests

• Flea beetles
• Cercosporea resedae