Indigofera tinctoria

Inflorescences and leaves an indigo plant ( Indigofera tinctoria )

The tropical indigo plant Indigofera tinctoria belongs to the legume family ( Fabaceae ). She wears unpaired pinnate leaves ( leaflets elliptic, entire ) and red butterfly flowers in clusters at the branch tips. The home of Indigo is apart from India, in tropical Africa and in China.

Use

The Indigofera is primarily the extraction of indigo, a valuable dye from the indigo is the color, a deep blue on the border with violet, her name.

The leaves of the indigo plant contain indican in a concentration of 0.2-0.8 %. This colorless, and water soluble derivative of the amino acid tryptophan represents the precursor of indigo, which has been obtained as follows:

Today the indigo dye is produced synthetically.

The dried, ground leaves of indigo plants are also used for hair dyeing. How to reach a dark brown to black color. They then merged with other plants such as henna ( " black henna ").

Cultural history of the Indigo

The cultivation of the indigo shrub native to the countries of origin of India and East Asia, and is already 2500 BC in Egypt detectable. Pliny describes the origin from India. The dye come before in the foam of the rivers and had been dumped at a particular Schilfart from which absammelten him the locals. In Europe, Indigo was rare until the 12th century, it was in small amounts over Syria and Alexandria imported from India. Around 1420 he is listed in a Venetian cargo list. From about 1600 it was introduced in large quantities by the Dutch East Indian, he pushed the work to the dyeing of textiles used woad.

Beroai is a Japanese term for imported indigo. Beroai was especially popular in the Bunsei (1818-1830) and the subsequent Tenpō period ( 1830-1844 ). An example is 36 Views of Mount Fuji by Katsushika Hokusai from the Tenpō period.

1878 Adolf von Baeyer succeeded for the first time fully synthetic production of indigo. Since 1897, synthetic indigo is sold commercially and has the indigo production from plant material almost completely replaced.

Cultivation

India

Indigo cultivation in India is occupied since ancient times. The plant is in Sanskrit as referred Nila ( Nile in Hindi ).

In the mid-19th century European capitalists had begun ( " planters " ) in British India in order to acquire in the area of ​​permanent settlement by the local landlords ( Zamindar ) cultivation rights by so-called Tinkathia - leases and the peasants ( raiyat ) help to undertake to cultivate 3/20stel their best land with the indigo plant. The farmers had to accept for the purchase of seed interest-bearing advances through intermediaries, with fraudulent contracts and interest rates of 50-500 % were common. However, the tenant did not receive guaranteed price, but a set at harvest time, which was below the market value. The problem was that Indigo did not integrate into the regular rotation. The dye was further processed in a local factory. When no longer profitable for the planters ( thikadari ) and their associates, the sale of indigo, they demanded from the peasants " release " ( tawan ) and lease charges ( sharahbeshi ). The exploitative practices led to the so-called 1859-62 Indigo unrest. The last remnants of the Tinkathia were not abolished until 1917/18 after the Champaran campaign ( north- eastern Bihar ) Mohandas Gandhi.

United States

Survey

On the territory of the present-day United States' first attempts to cultivate indigo, mid -17th century were made. Commercially successful, however, the Indigo cultivation was in the British colonies until after Elizabeth Lucas Pinckney (1722-1793) had introduced the plant in 1739 in South Carolina. After a series of unsuccessful attempts, she succeeded for the first time in 1747 to produce enough Indigo for delivery to the UK, where the climatic conditions do not allow the cultivation of the plant. Indigo from South Carolina was in high demand in the UK from then on, so he became one of the main agricultural products of the colony. Reached its peak production in 1773.

As during the Revolutionary War accounted for the British export market, the indigo cultivation in South Carolina was replaced by rice cultivation. After the war, the American indigo against the cheaper and better indigo from India could no longer claim. At the end of the 18th century cotton was the most important agricultural product in South Carolina and pushed the Indigo even further.

To a lesser extent Indigo was grown in Georgia and Louisiana. In Louisiana, the plant was grown by the French since 1718; to 1763 Indigo grew to become the most important export product, but was ousted at the end of the 18th century of more profitable agricultural products such as cotton, sugarcane and tobacco. In Florida, Indigo was introduced in the 17th century by the Spaniards.

Indigo cultivation and slavery

The Indigo cultivation required a lot of manual work, but not quite as much as the cultivation of sugar cane or rice. On the seed (April) a first section and the end of August followed on the North American mainland in early July often a second cut. Among the works that were incurred during the Indigo cultivation, was preparing, plowing, hoeing and leveling of fields, sowing, weed pulling and re- plowing for aerating the soil. After the cut, which takes place just before flowering, the plant had to be cut into pieces, pooled and further processed on the same day. Further processing included the waters in tubs or vats where the dye dissolved from the plant and achieved the desired blue color as a result of the fermentation process. In this phase, the processing of indigo was particularly obnoxious; the smelly ( and harmful to many contemporaries opinion ) Sud had, after he had been decanted from the rest of the plant are pounded relentlessly for hours on end, so that the dye was separated from the water and reflected in flakes on the tank bottom. After pouring off the water of the dye, which now had a pudding - like consistency, was spooned into cloth bags to overnight continues to lose water therein. The next day, the material was placed into molds, pressed and dried again, and finally cut into cubes.

On the indigo plantations of the North American colonies worked from the beginning slaves. The Spaniards had first used Indian slaves at Indigo cultivation, were then come to believe that the diseases from which these died in large numbers, were caused by the Indigo processing. The Indians were then replaced by slaves who were imported directly from Africa. Also worked in the French and British colonies on the indigo plantations of African slaves. Since the European colonizers had little experience with the plant, carried the expertise of these slaves, who were often already familiar with the indigo cultivation in Africa, to the rise of American indigo production to a significant extent. Unlike in many other areas of work the slaves were used on the indigo plantations in South Carolina and Georgia to the task system, ie they did not work under an overseer, a certain number of hours in the column ( transition system), but were given defined tasks for each day, which gave them a certain amount of control over their time, so they also needed to manage their care gardens and fields. The cultivation and processing cycles of indigo and rice were it to be cultivated both plants simultaneously from the same slave.