What are the main types of straw cotton?

Cotton grass, also known as African.cotton, originated in southern Africa and was cultivated and spread in the African continent earlier. Hutchinson( 195 1) divides cotton grass into the following five geographical species.

Persian cotton is distributed in Iran and its neighboring countries Turkey, Afghanistan, Iran, Iraq and the Mediterranean region. Annual shrubs are typical cotton and grass varieties.

2.Kuljianum (Kulga Cotton) is distributed in China, Xinjiang, Gansu and Central Asian countries. Annual shrub is the most early-maturing variety in grass cotton.

Acer is distributed in North Africa and sub-Saharan Africa, including desert oases in Ethiopia, Gambia, Egypt and Libya, as well as Saudi Arabia and Yemen. Perennial shrub with hard stems, many branches and tall plants.

4.Wightianum was introduced into western India from Persia and planted in the19th century. Annual shrub with hard stems, many branches and tall plants.

5.Africanum is distributed in Zimbabwe, Mozambique, Wales in Southwest Africa and transvaal province in South Africa. A perennial shrub with dense growth and many thin branches.

(2) Variety classification

1. Early maturity dwarf type: growth period 100d. The plant height is 50cm, and the main stem is thin and fluffy. The leaves are oval, wider than long and smaller. These flowers are small, yellow with purple spots. Cotton bolls are short, oval, weighing 0.5 ~ 1.2g, with small opening angle of cotton boll shell and strong floc content, which is difficult to harvest. Clothes percentage 19% ~ 32%, cashmere length 18 ~ 23mm. There are Jinta cotton, Dunhuang cotton and Anxi cotton.

2. Hairy and tall stalk type: the growth period is 130d .. plant height 1m, the stem is slightly thick, and the whole plant is densely fluffy. The leaves are big and the five leaves are short and round. The flowers are light yellow with purple erythema. Cotton bolls are oblate and peach-shaped, weighing 1.5 ~ 2g, with strong floc content and 24.0% lint percentage. The color of floc is white and brown, and the length of floc is 20 ~ 22mm. Mature late. In the case of heavy rainfall, angular leaf spot is serious. There are white cotton and purple cotton.

3. Perennial type: perennial plant, plant height 1.0 ~ 1.5m ... Yellow flowers with reddish purple spots, short hairs on petals and stems, entire bracts and open habits. Leaves and bolls are similar to early maturity dwarf type. Boll weight 1g, seed index 4.5g, lint percentage 27%, cashmere length 19mm. Light brown. After 9 hours of short sunshine treatment in Anyang, Henan Province, it can bloom half a month earlier and mature late. Under the natural conditions of Yacheng, Hainan, it can blossom and bear bolls, but the seed plumpness is poor. There are African cotton imported from America.