Quantifying the Effects of Water Deficit Stress Alleviation in Different Phenological Stages of the Cotton Plant and Its Impact on Growth and Yield

In order to be high yielding, the cotton plant must develop a vegetative framework big enough to allow the development and growth of fruits. Under water deficit conditions, the cotton plant faces restrictions on its vegetative and reproductive development, which, ultimately, leads to lower yields. Water deficit stress alleviation, either by rainfall or supplemental irrigation, will enable plants to grow and retain more fruiting sites. This paper describes a study designed to determine the effect of supplemental irrigation at different phenological stages in cotton. Results showed that supplemental irrigation increased whole-plant transpiration irrespective of phenological timing, but increased total dry biomass only when applied from MH to 1B and from 1B to MD. These effects did not impact significantly yield or WUE.