Conjunction use of irrigation water and rainfall with its impact on barley-water productivity in North of Nile Delta.

A field experiment was carried out at Sakha Agricultural Research Station Farm, Kafr El-Sheikh Governorate. The site is located at Middle North of Nile Delta area with 30°-57' N latitude, 31°-07'E longitude and altitude of about 6 metres above mean sea level. The experiment was conducted during the two successive winter growing seasons 2015/2016 and 2016/2017 to study the conjunction use of irrigation with rainfall on water productivity (WP) of barley. Irrigation treatments were; treatment A (rainfall) e.g. given only the sowing irrigation and left to rainfall during the growing season (control), treatment B (given one irrigation following the sowing irrigation), treatment C (given two irrigations after the sowing irrigation) and treatment D (given three irrigations following the sowing irrigation (traditional irrigation). The studied crop was barley cv. Giza 126 in a completely randomized block design with three replications. The highest average values of water applied and consumptive use were 45.7 cm (1914 m³/fed) and 37.0 cm (1554 m³/fed) under treatment D in the two growing seasons, respectively. The c ontribution percentages of rainfall to water applied (Wa) were 25.9% and 47.5 % for treatments D and A, respectively. Given only sowing irrigation (rainfall treatment, A) produced about 72% from that received 3 irrigations following the sowing one (Trt.D). The highest mean values of water productively (WP) and productivity of applied water (PWa) were recorded under treatment A in the two seasons and the values were 1.24 and 0.97 kg m^-3, respectively. For barley crop; grain yield, plant height, 1000-grain weight and the other yield components were the highest under irrigation treatment D.