The effect of different overhead heights, pressures and water stress to determine high uniformity and water relations of wheat as well as yield and yield components under overhead floppy sprinkler was addressed in this study. The experiments and measurements were designed and implemented at the experimental farm of ElSalhia, ElSharkia Governorate, Egypt during the winter season of 2018-2019 to study. The uniformity coefficient (UC) and uniformity distribution (UD) were calculated under five levels of pressure (100, 150, 200, 250 and 300 kPa), four overhead heights (1, 2, 3 and 4 m) and water stress (20, 40, 60, 80 and 100% of evapotranspiration (ETc)). The results indicated that the highest values of UC and UD 72.14 and 58.13%, respectively were succeeded with pressure of 200 kPa and 3 m height for overhead floppy. Also, the results showed that water stress from 20 to 100% ETc with optimum operating conditions were carried out to get up high wheat production. The total yield and yield components were increased with decreased water stress. Also, the total yield was increased with increasing ETc from 20 to 100%. The grain and straw yield values were increased by 68.98, 66.55, 55.66 and 35.35% & 69.70, 64.29, 50.00 and 44.44% compared with 20% for overhead floppy. The maximum yield production and components were achieved with 100% ETc, while water use efficiency (WUE) with 20% ETc was maximum value. Finally, under the current experimental conditions, it could be concluded that the application of irrigation water 100% ETc under pressure of 200 kPa and 3 m overhead height with high UC and UD for overhead floppy sprinkler was the best system for obtaining high wheat yield production. On the other hand, using the application of irrigation water 80% ETc could be suggested to get high yield production and save water which will lead to deal with future water scarcity.

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The scarcity of water become global problem, the "A" frame structure system is commercially extended in the hydroponics industry. The objective of this work was to evaluate the impact of different "A" frame angle design for NFT system design, water depth in pipes and pipes position, on growth of two leafy vegetables parameters. The treatments were the angle of "A" frame design (A o ), (45° and 60°), Water depths (4 and 6 cm), and leafy plants (lettuce and mint). The results indicated that, the changing angle from 180° to 60° and 60° to 45° decreased the occupied surface area by 45.0 % and 25.76 %, respectively. The light intensity values were decreased by changing the "A" frame angle from 60° to 45° by 26.4 % for lettuce and 32.0 % for mint. Changing the position of the pipe from center to bottom decreased the light intensity for lettuce by 9.2 % and 11.7 % for 45° and 60° angels, respectively. While increased by 21.2 % for mint with 45° angle only. Root length and stem diameter were increased by changing angle from 45° to 60° and water depth from 4 to 6 cm for both mint and lettuce plants. Optimal yields of lettuce and mint plants grown in "A" frame hydroponic system with 45° angle like those plants grown with 60° angle, indicating from no significant differences in the production of lettuce and mint plants. The "A" frame design with 45° angle can be recommended for production of lettuce and mint.

The main objective of the present study is to evaluate two types of sprinklers (impact sprinkler and rotating sprinkler), impact sprinkler (average nominal discharge from 780 to 1660 ℓ/h at operating pressure from 100 to 400 kPa) and rotating sprinkler (average nominal discharge from 360 to 730 ℓ/h at operating pressure from 50 to 350 kPa) to determine optimum operating conditions that achieve high application uniformity. The coefficient of uniformity (CU) and distribution uniformity (DU) were evaluated under different levels of operating pressure and constant riser height of 1.0 m. It was concluded that the operating conditions that achieved high coefficient of uniformity and distribution uniformity was operating pressure of 200 kPa for impact sprinkler. The results showed that the highest values of CU and DU were 90.55 % and 68.10 % for impact sprinkler respectively while for rotating sprinkler with combination of trajectory angles (20 o , 25 o ), the corresponding values of CU and DU were 85.60 % and 60.50 %, respectively. Also, to achieve high percentage of overlap simulation model was used, it appeared that the spacing between sprinklers should be higher than or equal to 50 % of wetted diameter to avoid water lose and minimize irrigation system cost.

during the summer 2016 growing season in a sandy soil with snap bean (Phaseolus vulgaris L.) under drip irrigation system. The main goal of the present work was to study effect of different emitters and water deficit (T 1 : 100 %, T 2 : 75 % and T 3 : 50 % of evapotranspiration (ETc)) on snap bean yield and water use efficiency (WUE). Two different emitters manufactured (in-line 'Em 1 ' and on-line 'Em 2 ') were evaluated with lateral length 50 m at different operating pressures of 50, 100, 150 and 200 kPa. The obtained results indicated that, the coefficient of uniformity (CU) increased with increasing operating pressure from 50 to 100 kPa and decreased with increasing operating pressure from 100 to 200 kPa. The first treatment produced high yield without significant differences of the second treatment, so, concerning the different irrigation regimes the 75 % ETc treatment gave a remarkable yield and pronounced water saving equal 25 % from applied water of T 1 therefore it is technically and economically recommended and the best one for saving water. Water use efficiency was the highest in 50 % ETc, but 75 % ETc was the best one economically. Yield was the greatest when fresh and adequate irrigation was applied. Snap bean yield was significantly affected in a linear relationship (r 2 ≥ 0.90) by deficit irrigation conditions.