الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In Egypt, water scarcity is the major factor that limits the ambitious hopes to expand and increase agricultural area to meet the present gap between food production and consumption. The agricultural activity consumes about 80 to 85% of the water resources in Egypt. The pressure of population growth and increasing domestic and other sectors demand for water as well as the expected negative impact of climate change represent serious competing challenges for the agricultural sector. To meet these challenges, good governance which aims to reduce losses and increase benefits per unit of water should be adopted. This could be achieved by raising the on-farm irrigation efficiency through the selection of proper and efficient irrigation system, laser leveling of the field, selection of drought tolerant cultivars, and the use of modern irrigation techniques such as Regulated Deficit Irrigation (RDI). On the other hand, the proper management of low quality irrigation water, such as agricultural drainage water and low to moderate saline water, could be used as a tool to increase the overall efficiency of the limited water resources in Egypt.This research aimed at studying the effect of using different amounts of irrigation water under surface and sprinkler irrigation systems on the production of wheat crop grown in calcareous and sandy soils of Nubaria region. Also to study the effect of using low quality irrigation water (agricultural drainage water - different levels of irrigation water salinity) on the productivity of wheat crop. The specific objectives were to: Conduct field experiments to test the effect of deficit irrigation treatments on the productivity of two wheat cultivars, their yield components, plant height, leaf area index, protein%, potassium%, and other wheat-water parameters. Determine the actual and applied amounts of irrigation water, water use efficiency, and water productivity values of wheat cultivars under surface and sprinkler irrigation systems in calcareous and sandy soils. Conduct a field experiment to test the effect of irrigation with agricultural drainage water on the productivity of wheat crop, its components, growth parameters, quality parameters, and wheat-water relations. Conduct a green house experiment to test the effect of two soil salinity levels, two wheat cultivars, and five irrigation water salinity levels on wheat grain and biological yields, yield components (1000-grain weight, spike length, harvest index (HI), and number of spikes/pot), salinity build-up in the soil, and germination % under calcareous soil conditions. Develop a relationship between amounts of applied irrigation water under deficit irrigation conditions and wheat yield. Develop a relationship between salinity levels of irrigation water and wheat yield. Recommend a suitable production package for wheat crop at Nubaria region. To achieve the goals of this study, field and green house experiments were conducted to study the effect of deficit irrigation method as well as irrigation using low quality water (e.g. agricultural drainage water and different levels of saline water) on the productivity of wheat crop under surface and sprinkler irrigation systems at the Nubaria region. First experiment: ”Effect of applied different amounts of irrigation water under surface and sprinkler irrigation systems on the productivity of wheat, yield components and water use efficiency”. A field experiment was conducted on wheat crop at the research farm of Nubaria Agricultural Research Station (calcareous soils and surface irrigation system) at North Tahrir area during the 2010-2011 and 2011-2012 growing season. The same experiment was conducted at the research farm of Ali Mubarak Research Station (sandy soils and sprinkler irrigation system) at Al Bustan area during the 2011-2012 growing season. A randomized complete blocks design (RCBD) with three replicates was used to conduct the field experiment. Eight irrigation treatments were tested (T1; 100% of crop water requirements at all growth stages, T2; 75% of T1, T3; 50% of T1, T4; 50% T1 only at tillering stage, T5; 50% of T1 only at booting stage, T6; 50% of T1 only at filling stage, T7; 50% of T1 only at tillering and filling stages, and T8; sowing irrigation only and it was left without irrigation depending on rainfall). The T8 treatment was applied only under the surface irrigation system only. Sakha 93 wheat cultivar was used during the 2010-2011 growing season, while Gemmiza 9 wheat cultivar was used during the 2011-2012 growing season. All recommended cultural practices for wheat crop grown under calcareous and sandy soils conditions were followed. Field and Laboratory Measurements: Soil physical characteristics (particle size distribution and soil texture class, moisture characteristic curve, bulk density, and saturated hydraulic conductivity). Soil chemical characteristics (electrical conductivity of soil paste extract, pH, cations and anions, organic matter, cation exchange capacity, and calcium carbonate contents). Wheat yield, yield components and quality, and growth parameters: Biological yield (Mg ha-1 ), grain yield (Mg ha-1 ), yield components (1000 grain weight (g), harvest index (HI), number of grains per spike, number of spikes per square meter, and spike length (cm)) were recorded at harvest time. Protein and potassium percentages in the grain and straw. Plant height (cm) and leaf area index. Crop water-use parameters: Daily Class A pan data, and gravimetric soil samples for the determination of water consumptive use values (CU). Plant-Water Relations: Leaf water potential (Ψleaf), proline hormone concentration, canopy temperature, plant stress index, applied irrigation water, consumptive use values, water use efficiency, and water productivity. The main results can be summarized as follows: A. Under calcareous soils and surface irrigation system: 1. Soil texture is sandy clay loam, total calcium carbonate values were 293.7 and 355.3 g kg-1, soil salinity values were medium to high (3.07 and 7.48 dS m-1), pH values were 7.91 and 8.18, average field capacity values were 24.39 and 24.88%, average wilting point values were 11.53 and 12.36%, and average available water values were 12.86 and 12.52%. 2. The highest average biological yield of wheat was 14.40 and 22.68 Mg ha-1 for the first and second seasons, respectively, for the full irrigation treatment (T1). 3. The highest average grain yield of wheat was 5.62 and 7.65 Mg ha-1 for the first and second seasons, respectively, for the full irrigation treatment (T1). 4. Grain yields under deficit irrigation treatments T2, T3, T4, T5, T6, T7 and T8 were less than that of T1 treatment by 20.71, 29.57, 23.10, 22.64, 14.24, 27.72, and 47.31% in the first season, and by 22.35, 35.82, 21.67, 12.42, 6.27, 27.45, and 60.13% in the second season, respectively. 5. During the both growing seasons, imposing water stress during the whole season will have a slight effect on harvest index values. 6. Average spike length values decreased with increasing water stress under all treatments compared with full irrigation treatment (T1). 7. Imposing water stress during the whole season will not significantly reduce the 1000 grain weight. 8. Imposing water stress will significantly reduce wheat plant height except for deficit irrigation at tillering or grain filling growth stage treatments. 9. The LAI values for Sakha 93 cultivars were higher than those of Gemmiza 9 cultivars. Also, imposing water stress on Sakha 93 cultivar at different growth stages negatively affected LAI values as compared with the effect on Gemmiza 9 cultivar. 10. Protein content in the grain increased under the deficit irrigation compared with the full irrigation treatment. 11. Imposing water stress during the whole season will increase potassium content in wheat grains. 12. Applying deficit irrigation resulted in considerable accumulation of proline in plant leaves compared with that of full irrigation. 13. Leaf water potential values decreased as plants become close to maturity and/or under deficit irrigation conditions. 14. Canopy temperature increases as plants become close to maturity and/or under deficit irrigation conditions. 15. By the end of the growing season, stress index value was lowest in T1 treatment and was highest in rainfed treatment (T8). 16. Applying deficit irrigation at tillering + filling stages (T7) caused the highest increase in stress index values as compared to the other T4, T5, and T6 growth stage treatments. 17. Amounts of applied water (AIW) were 5791, 4727, 3662, 5007, 5202, 5035, 4446, and 1876 m3ha-1 in the first season, and were 5985, 4871, 3759, 4868, 5448, 5413, 4296, and 2085 m3ha-1 in the second season, for the T1, T2, T3, T4, T5, T6, T7, and T8 treatments, respectively. 18. Water consumption use (WCU) values were 3069, 2546, 1990, 2876, 2901, 2502, and 2032 m3ha-1 in the first season, and were 3062, 2658, 2322, 2700, 2687, 2708, and 2463 m3ha-1 in the second season, for the T1, T2, T3, T4, T5, T, and T7 treatments, respectively.