الفهرس 
Approval sheetOnly 14 pages are availabe for public view
 |  | from | 111 |  |  |
| | | from | 111 | | |
Abstract
Three experiments were carried out at the experimental farm of the Soils and Water Depart., Faculty of Agric., Assiut University, situated at a latitude of 27o 11’ 9.20’’ N, longitude of 31o 10’ 24.63’’ E and 52 m above the sea level during the summer season of 2016 to study the impact of surface and subsurface drip irrigation and number of fertigation managements as splitting the amount of fertilizers into doses (3D = 3 doses, 6D = 6 doses, 9D = 9 doses and 12D = 12 doses) on the yield and water use efficiencies of two squash varieties, cucumber and maize. The experiments were laid out in split spilt block design arrangement with three replicates. The results may be summarized as it follows: 1- Squash experiment: A- The highest mean values of number squash fruits (116875 No/fed.) and squash fruit yield (15.75 tons/fed.) and water use efficiency (7.87 kg/m3.) were obtained from subsurface drip irrigation. Appling the same amount of water (2001.58 m3) with subsurface drip irrigation increased the yield as compared with surface drip irrigation. B- Dividing the amount of fertilizer recommended by CAAE (2016) ( 200 kg ammonium nitrate, 24 kg P2O5 fed.-1 as phosphoric acid and 150 Kg potassium sulfate) were applied through fertigation in 12 doses produced the highest yield (16.87 tons/fed.) and WUE (8.43 kg/m3.) Increasing number doses from 3 to 6, 9, and 12 doses caused steadily increase in squash fruits yield from 7.04 to 9.55, 13.68, and 16.87 tons/fed and WUE steadily increase from 3.53 to 4.77, 6.83 and 8.43 kg/m3. C- The highest mean values of water use efficiency were recorded from subsurface drip irrigation with splitting the same amount of fertilizer to 9 and 12 doses in both varieties. D- Response of squash varieties Fadwa squash hybrid produced higher yield of 15.36 tons/fed., compared to Eskandarany variety of 8.20 tons/fed. 2- Cucumber experiment: A- The highest mean values of number cucumber fruits (96375 No/fed.) and squash fruit yield (10.68 tons/fed.) and water use efficiency (4.70 kg/m3.) were obtained from subsurface drip irrigation. Appling the same amount of water (2274.37 m3) with subsurface drip irrigation increased the yield as compared with surface drip irrigation. B-Dividing the amount of fertilizer recommended by CAAE (2016) (200 kg ammonium nitrate, 24 kg P2O5 fed.-1 as phosphoric acid and 150 Kg potassium sulfate) were applied through fertigation in 12 doses produced the highest yield (12.96 tons/fed.) and WUE (5.70 kg/m3.) Increasing number doses from 3 to 6, 9, and 12 doses caused steadily increase in cucumber fruits yield from 5.91 to 7.43, 10.30, and 12.96 tons/fed and WUE steadily increase from 2.60 to 3.27, 4.53 and 5.70 kg/m3. C- The highest yield and yield components of cucumber and WUE were recorded with using subsurface drip irrigation with splitting the same amount of fertilizer to 9 and 12 doses. 3- Maize experiment: A-Applying surface and subsurface drip irrigation produced maize grain yield and water use efficiency of 4.14 tons/ fed, 1.32 kg/m3 and 4.93 tons/ fed., 1.59 kg/m3, respectively. B- Dividing the recommended amount of fertilizers by CAAE (2016) (365 kg ammonium nitrate, phosphate rate of 31 kg P2O5 fed.-1 potassium at rate of 24 kg K2O fed.-1 as potassium sulfate 50 Kg) to number of doses of 3, 6, 9, and 12 doses increased the maize grain yield and WUE steadily from 3.61, to 4.25, 5.29 and 4.98 tons/fed and 1.16, 1.37, 1.68 and 1.60