ISSN: 0041-3216 (Online), 0041-3216 (Print)
Volume 64 Number 3
Irrigation scheduling for winter sorghum in South Gujarat, based on IW /CPE ratios
An experiment to determine schedule irrigation in sorghum was conducted at the Main Irrigation Research Centre, Navsari, India, during the winter seasons of 1977-78 and 1978-79. Two depths of irrigation water, 60 mm (I1) and 80 mm (I2), each measured by water meter, were evaluated at four IW/CPE ratios, R1 = 0.60, R2 = 0.75, R3 = 0.90 and R4= 1.05 during both years. Five irrigations each of 80 mm depth at an 1IW/CPE ratio of 0.90 proved to be optimal for the winter sorghum. It gave maximum grain (4.26 t ha-1) and stover (9.34 t ha-1) yields with a water-use efficiency of 11.67 kg ha-1 mm-1 of water applied. A net profit of Rs. 3738 ha-1 (US $ = 280 ha-1) was obtained in this treatment. The observed consumptive use of water by winter sorghum was 397 mm which was significantly (P= 0.01) correlated (r= +0.95) with the USWB Pan Evaporation Value for the same crop growth period.
Keywords: Sorghum yield; Evapotranspiration; Irrigation; Water-use efficiency