Question

Name the various types of cotton on the basis of the length and the strength of the fiber.

Answer 1

Hint: It is also known as cash crop. It was discovered around 5500 BC. It is derived from Arabic word.

Complete answer:
The term cotton has been derived from Arabic word ‘qutn’ and entered in the 12th century. It was discovered in 5500 BC at the Neolithic Site of Mehrgarh in Balochistan in Pakistan. It is grown around the seeds of the flowering plant named Gossypium which belongs to the mallow family named Malvaceae out of which the cotton is harvested. It is soft in texture and fluffy which is covered by a protective case.

It is cultivated in a frost-free period with plenty of sunshine receiving a moderate rainfall of about 60 to 120 cm. It requires plenty of water as well which is approximately 8000 to 10000 liters for one kilogram of cotton and dry region it may require more. Thus, it is also known as a thirsty crop. The period of cultivation starts from the month of February to the beginning of June.

Regarding types of cotton there are mainly four types of cotton:
Gossypium hirsutum which is an upland cotton grown mainly in Central America, Mexico, Caribbean and Florida which contributes to 90% production of the world. The length ranges from 20-32 mm. Gossypium barbadense is another type of cotton also known as extra-long staple cotton which is native in South

America and contributes another 8% production of the World. The length ranges from 35-45 mm.
Gossypium arboreum is a tree cotton which is mainly grown in India and Pakistan and contributes less than 2%. The length ranges from 10-25 mm.

Gossypium herbaceum is a levant cotton grown in Africa and Arabian Peninsula contributing less than 2% of the total production of World. The length ranges from 10-25 mm. Regarding the strength of cotton then it is moderately strong fiber having tenacity of 3-5 gm and is generally affected by moisture. The strength of wet cotton is 20 percent which is greater than dry strength.

Note:
i) From 2019 World Cotton Day is being celebrated on 7th October.
ii) The machines with which cotton is harvested are known as strippers and pickers.
iii) It is considered as the most important textile fiber.