Question

State two geographical conditions suitable for the cultivation of rice?

Answer 1

1. Temperature: Rice cultivation is conditioned by temperature differences at different phases of growth. It grows best in warm and humid areas. The critical mean temperature for flowering and fertilisation ranges from 16°C to 20°C whereas during ripening, the range is from 18°C to 32°C. Temperatures beyond 35°C affect not only grain retention but also grain filling. It requires ample sunshine and water. It can grow on different altitudes as long as its temperature requirements are satisfied. For example, it is grown in Kashmir at a height of 2000 m and in the Kuttanand region of Kerala, which is below sea level.
2. Rainfall: Rice requires good rainfall in the range of 150 to 300 cm. In fact, rice is mainly an irrigated crop. It requires much water both in and upon the soil. During the earlier phase of its growth, it requires 5 to 10 cm of standing water. Therefore, the monsoon lands are best suited for rice production as heavy irrigation is required. Deltas, estuaries, flood plains, valleys of rivers, and coastal plains with heavy soils provide excellent conditions for the cultivation of rice.
3. Soil: Deep, fertile clayey or loamy soils are well suited for rice cultivation. Rice thrives in the alluvial soils along the river banks. The soil should be able to retain standing water in the field. This phenomenon protects the plants from pests that cannot survive underwater. Soils need manure and fertilisers to produce a higher yield.