Effect of Timing of Last Irrigation on Growth, Yield and Water Productivity in Cotton under Gezira Conditions

Abstract

A Field experiment was conducted for two seasons (2015/16 and 2016/17) at Gezira Research Station Farm (GRSF) to determine the optimum timing of the last irrigation for the newly released BT. cotton (Seeni1) along with non BT. cotton (Hamid) on the basis of scheduling irrigation approach. The experiment was executed in a split plot design with the two cotton cultivars comprising the main-plots and eight timings of last irrigation as sub-plots. All treatments were replicated three times. Delay of final irrigation significantly increased number of sympodia per plant and plant height. Irrespective of cotton cultivar, 27 WAS recorded the highest number of bolls/plant in both seasons. Cotton yield, water productivity and fiber quality were highly affected by irrigation treatments. Delay of final irrigation up to 21 WAS resulted in higher crop and water productivities. Moreover, delaying the last irrigation after 21 weeks showed no improvement in cotton fiber quality. These results indicate that excessive irrigation might not produce more yield or improve cotton quality.