Conjunctive use of rainfall and irrigation for wheat crop in North Nile Delta

To find out the impact of rainfall and irrigation on wheat crop and its water functions, a field trial was carried out at Sakha Agricultural Research Station, North Nile Delta during the two seasons 2015/16 and 2016/17. Treatment A which consists of rainfall only has the lowest applied water (Wa), consumption use (CU) and crop yield, The traditional irrigation treatment E consists of no missing irrigation at any growth stage. Average contribution of rainfall in water applied was52.5, 32.4, 32.8, 32.3 and 27.1% for treatments A, B ( skipping irrigation during vegetation), C (skipping irrigation during flowering stage), D (missing irrigation during milking stage) and E (no skipping irrigation), respectively. Skipping irrigation during vegetation stage caused a slight decrease in wheat yield. In comparison with the traditional treatment, mean water savings were 48.5, 16.5, 17.4 and 16.3 %, while the decrease in crop yield was 43.4, 21.2, 11.2 and 5.9 % for treatments A, B, C and D, respectively. Most of yield components showed similar trends with those of applied water.