Abstract

This study investigates the optimum water requirements of Sugarcane planted in different months under rainfall and irrigation management, using CROPWAT model at Finchaa Valley in view of the importance of efficient water use as a key to grow crops and satisfy water demand. Analysis of soil physical properties was performed following the standard field and laboratories procedures and methods. The result of investigation indicated that total and monthly crop (irrigation) water requirement of sugarcane varied with the first watering month, ranging from 1554.6 mm (764.5 mm) to 1677.8 mm (1090.9 mm) with the average value of 1614.45 mm (903.8 mm). per growing season The highest and lowest amount of both rainfall and irrigation water demands were obtained for the first watering month (from irrigation or rainfall) of May and August respectively. The finding of the study also implies that, irrespective of the planting and harvesting months’ irrigation water provision is not required in June, July and August months for sugarcane cultivated in Finchaa Valley under current climatic condition. Thus, applying fixed depth of irrigation water at a fixed frequency to different soil types throughout the growing season probably lower water use efficiency and reduce crop yield. It is recommended to use CROPWAT model for proper and effective irrigation scheduling for efficient use of available water and improved yields of sugarcane.

Key words: Sugarcane, first watering month, water requirement, CROPWAT model.