Question

_______ soil is suitable for the cultivation of cotton.
1. Alluvial
2. Laterite
3. Terai
4. Regur

Answer 1

Hint: This soil is rich in contents like clay, loam, etc. Also, it has impressive water retention capabilities. In addition, it is a soil formed from the breakdown of lava matter.

Complete answer:
Almost all well drained soils support the growth of cotton. However, the most suitable soils that result in high yields are- deep well drained sandy loam soils, with sufficient clay, organic matter and also, a moderate concentration of nitrogen and phosphorus. Often the best yields are achieved in loamy soils as they are rich in calcium carbonate. Let us examine the options-
1. This is an incorrect choice because though the alluvial soil is quite rich in organic content like humus but its nitrogen content is quite low. It is considered as the most fertile soil and the entire northern plains of India are made of alluvial soil and we know that the cotton soil is made up of lava content and rich in nitrogen concentration.

2. Laterite is a soil type which is abundant in iron and aluminum and is considered to have formed in hot and wet tropical regions. Nearly all laterite soil types are in rusty-red coloration, due to the presence of high iron oxide content. It forms in relatively more humid regions for the cotton to grow thus, it is an incorrect choice.

3. The terai soils are a subtype of the alluvial soil kind; they’re rich in nitrogen and organic matter but are deficient in phosphate. This choice seems to be quite appealing, yet it is an incorrect choice because alluvial soil area receives good rainfall and cotton grows in areas with lesser rainfall.

4. Black soil is also called Regur soil. As the name suggests it is black in color, formed of lava content, rich in nitrogen and phosphorus and thus, by all means, ideal for growing cotton. This type of soil is a typical feature of the Deccan trap (Basalt) region (North-West Deccan plateau). Hence, it is the right choice.

Therefore the answer is 4. Regur
Note:
Cotton grows in areas where intensive irrigation isn’t possible which explains how black soil can help it sustain in the low rainfall areas; regur can retain water and moisture due to the presence of clay content and thus provide nutrition to the crops. Such soils are rich in lime and consist of a mixture of sand, clay and organic materials.