Question

Blue dye is obtained from the leaves of
A) Indigofera tinctoria
B) Opium
C) Aloe
D) Dalbergia sissoo

Answer 1

Blue dye is also known as an indigo dye and is obtained from the leaves of the plant that is mostly herbaceous shrub and its leaves are pinnately compound. This plant belongs to the family Fabaceae and possesses pink or violet-colored flowers.

Complete answer:
Option (A): Indigofera tinctoria is a shrub belonging to the family Fabaceae that is also called true indigo as it was one of the sources of indigo or blue dye. The leaves of this plant are light green and pinnately compound with pink or violet flowers.
Option (B): Opium is dried latex, used as a narcotic drug that is obtained from the seed capsules of opium poppy i.e., Papaver somniferum that belongs to the family Papaveraceae.
Option (C): Aloe is a genus containing 550 species of flowering succulent plants, among which Aloe vera is the most widely known species that belongs to the family Asphodelaceae. It is mostly cultivated as a source for pharmaceutical purposes.
Option (D): Dalbergia sissoo is commonly known as the North Indian rosewood. It is a large deciduous tree that possesses long, leathery leaves and white or pink-colored flowers. It belongs to the family Fabaceae and is mostly used for making timber, pesticide, fuelwood, etc.

Hence, the correct option is (A).

Note: The blue or indigo dye is obtained from the leaves of Indigofera tinctoria. The leaves of this plant naturally contain a glycoside i.e., indican which is converted into blue dye i.e., indigotin after the soaking and the fermentation process.