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Water is limited resource. This is considered to be one of the main challenges for future water policy. Saving water and energy is a requirement to ensure the viability of pressurized irrigation systems. Designing and optimizing sprinkler irrigation systems are mainly based on achieving appropriate hydraulic performance. Spray nozzles being very often a critical component in determining the final quality of the product or the sprinkler irrigation efficiency process. The engineering design factors of sprinkler affect sprinkler system performance. So, this study focuses on some engineering design factors (three different nozzle characteristics (1, 2 and 3) and operating pressures from 150 to 250 kPa), comparing with designed nozzle (No 4) to improve brass impact sprinkler performance. This study sited on Giza region at National Laboratory for testing the components of irrigation networks and field drainage, Agricultural Engineering Research Institute AEnRI, Agricultural Research Center ARC. The result of Christiansen uniformity coefficient CU indicated that designed nozzle No 4 achieving good performance according to American society of Agricultural and Biological Engineers ASABE 2001 starting with operating pressure 150 kPa 74.05 % while nozzle No 3 starting with 175 kPa achieved 75.23 %. Also it was found that nozzle No 4 increasing flow rate by 43.48 %, precipitation rate by 19.92 %, rotation speed by 24.96 %, decreasing coverage radius by 28.38 % and the jet breaks up sufficiently to achieve an adequate water distribution pattern and obtained good droplet size comparing with nozzle No 3. It was found that sprinkler layouts 9m Х 9m overlapping achieved acceptable uniformity at operating pressure 150 kPa. Also the result indicated that nozzle No 4 saved operating time ratio by 26.87 % and decreased over minimum application targeted irrigation depth by 66.7 % at the same overlapping distances and at the same operating pressure 150 kPa.

Drip irrigation systems have become a major part of developing agriculture in Egypt and the aim of this research was to obtain the best performance from irrigation systems management using locally modified and original emitters. The experiments were carried out at the National Irrigation Laboratory of the Agricultural Engineering Research Institute. The emitters were tested and calibrated under different operating pressures (0.50, 0.75, 1 and 1.25 bar) to determine emitter flow rates and emitter emission uniformity (EU) and manufacturing variation coefficient (CV). The original emitter performance was determined using the relationship between emitter flow rate (2 lh−1) and operating pressure, with data indicating that the EU was 98.5%, at a CV of 2.3% and actual flow rate was 1.8 lh−1 for the original emitter. The EU was 93.8% with a CV of 5.2% and actual flow rate of 2.02 lh−1 for the modified emitter. For original emitter performance at 4 lh−1, data indicated that the EU was 96%, with a CV of 4.8% and actual flow rate of 3.78 lh−1. The EU for the modified emitter was 95% with a CV of 2.7% and actual flow rate of 4.5 lh−1. The emitter exponent values were 0.41 to 0.44 for modified and 0.37 to 0.38 for original emitters.

It's a fact that trickle irrigation systems became a major part for developing agriculture in Egypt for that, the aim of this research was reaching the highest values from irrigation systems management as the result of using bypass-technique, this new technique was done by installing microtubes at third last of trickle line. The laboratory experiments were carried out at the National Irrigation Laboratory of Agricultural Engineering Research Institute. The laterals were tested and calibrated under different operating pressure (0.50 -0.75 -1.00 -1.25 bar) for measuring emitter flow rates and determining emitter's emission uniformity (EU) and its manufacture (CV). The following results were found:-1-The emitters' performance was determined by using relationship between emitter flow rates (L/h) and operating pressure (bar), data indicated that the emission uniformity (EU) was 95.68% (Excellent), at CV of 3.78% (Excellent) according to test standard (ASAE 1996) and actual flow rate was 14.08 l/h. 2-Installing microtubes., distance between emitters=0.5, 1.5 and 3 meters, present the following results respectively, where emission uniformity equal to 90.9%, 96.28% and 98.06 % (Excellent) in compare with traditional which in range of 89.34%, 95.52% and 96.03% respectively, emitters performance equation which was been in power relation in between average of flow rates (L/h) and pressure (bar).It is recommended that bypass-technique gave a new advantage for trickle irrigation systems.

The herbicide butralin (Amex) was injected at the recommended rate ( 2.5 Kg/fed) through subsurface and surface drip irrigation systems with two flow rates of 8 and12 lph/m under sandy soil conditions of the newly reclaimed areas of Egypt.Maximum cucumber yield of 8360 kg/fed. was achieved using subsurface drip irrigation systems at 8 lph/m flow rate and 50 cm emitters spacing, in manure sandy soil Water use efficiency (WUE) ranged from 4.042 to 3.955 kg/m 3 with 8 and 12 lph/m flow rates, respectively for subsurface irrigation systems 50 and 33 cm emitters spacing in manured sandy soil. The application of herbicide butralin (Amex) with subsurface drip irrigation systems, 50 cm emitters spacing proved more suitable to increase cucumber yield, and to achieve more uniformity in water distribution (8 lph/m) for irrigation systems. No butralin (Amex) residues were detected in cucumber yield produced under subsurface drip irrigation systems at 10 cm depth for the 50 cm emitters spacing and 8 lph/m flow rate.