What is the Necessity of irrigation?

Throughout the crop period adequate quantities of water is required near the root zone of the plants for their growth. At times during the crop period the rainfall may not be adequate to fulfill the water requirement. The intensity of rainfall is practically uncertain and beyond the control of human power and it may not be well distributed throughout the crop season or the culturable area. So, irrigation becomes absolutely necessary to fulfill the water requirement of crops. The following are the factors which govern the necessity of irrigation,

(a)Insufficient Rainfall:

When the seasonal rainfall is less than the minimum requirement for the satisfactory growth of crops, the irrigation system is essential.

(b)Uneven Distribution of Rainfall:

When the rainfall is not evenly distributed during the crop period or throughoutthereculture able area the irrigation is extremely necessary.

(c)Improvement of Perennial Crops:

Some crops like sugarcane, cotton, etc require water throughout the major part of the year. But the rainfall may fulfill the water requirement in rainy season only. So for the remaining part of the year, irrigation becomes necessary.

(d)Development of Agriculture in Desert Area:

In desert area where the rainfall is very scanty, irrigation is required for the development of agriculture.