Comparison of the Water Use Dynamics of Cotton Grown with Sorghum Under Deficit Irrigation

Evaluation of the water use of drought-tolerant crops is necessary in assessing its potential under limited water conditions. In 2017 and 2018 growing seasons, field experiments were conducted in New Deal, Texas to evaluate the performance of cotton grown together with sorghum under four different levels of deficit irrigation (DI). The target irrigation amounts were 51 mm (extreme DI), 127 mm (severe DI), 203 mm (moderate DI), and 279 mm (mild DI). For both years and crops, the soil water depletion measurements showed differences by soil layer and irrigation amount. Results were analyzed to develop a functional relationship between soil water extraction patterns and water use efficiency of cotton and sorghum when grown under deficit irrigation.