ABSTRACT
A field experiment was conducted for three growing seasons to study the effects of seasonal water use and applied N fertilizer on grain yield and water productivity indices of wheat in an arid region. The results revealed that the yield response to N was associated with water application levels. The water productivity indices were influenced by irrigation strategies, and deficit irrigation effectively boosted productivity of irrigation water (WP~I~). The highest WP~I~ was obtained at a seasonal irrigation water of 156βmm for different levels of applied nitrogen~.~ For levels of applications 70% of the required nitrogen, required nitrogen, and 120% of the required nitrogen, WP~I~ ranged between 0.93 and 2.28, 1.30 and 2.75, and 0.98 and 2.47βkg m^β3^, respectively. The data generated here indicate that maximum water productivity (WP~E~) would be achieved when 98βkgβN ha^β1^ is combined with 156βmm of supplemental irrigation (2.72βkg m^β3^). Consequently, when limited irrigation water is combined with N fertilizer appropriate management, water productivity can be substantially and consistently increased in arid regions. Copyright Β© 2011 John Wiley & Sons, Ltd.