Egypt depends on the Nile River as a major source of water, it provides about 76.3% of its water requirements, other water sources provides about 23.7% of total water requirements. Agriculture sector is the main consumer of water in Egypt as it consumed about 85.9% of the total actual consumption of water in 2009. The main problem of the present paper is the decrease in the efficiency of water use in Egyptian agriculture. The objective of paper is to assess the efficiency of water use in agriculture in the old and new land Egypt through the use of partial efficiency measures. Results showed that in average of the cost of irrigation per feddan during the period (1998-2009), that was for winter crops in the old lands as follows: 85.3, 105.8, 119.3, 127.3 pounds/feddan for faba bean, sugar beet, alfalfa sustained, wheat at a cost of irrigation per feddan of which respectively. For summer crops in old land cost was about 114.7, 129.5, 139.8, 156.2, 217.8, 606.1 pounds/ feddan at a cost of, sesame, soybean, peanut, corn, rice, sugar cane, respectively.   For the winter crops in the new lands irrigation cost per feddan was about L.E 99.3, 169.0 for garlic and onion respectively. Summer crops in the new lands irrigation costs for watermelon, cucumber, potatoes, eggplant, peppers, and tomatoes were as follows: L.E 92.4, 133, 138.7, 139.8, 157.7, 194.3 pounds/ feddan respectively. The results of the statistical analysis of partial-efficiency measures showed that, according to the criterion of net revenue from the water unit - winter crops on the old land as follows: alfalfa, wheat, faba bean, and sugar beet. As for the summer crops of old land the results showed of the statistical estimate of the partial-efficiency measures that peanuts, corn, sesame, sugar cane, rice, soybeans respectively. In the new lands the results of statistical analysis for the partial- efficiency measures, according to the standard net return of the water unit for winter crops were garlic followed by the first crop of onions. As for the summer crops, the results of statistical analysis of partial -efficiency measures, according to the standard net return of the water unit came summer crops in the new lands, were as follows: potatoes, tomatoes, watermelon, cucumber, eggplant, pepper. The results in general indicated the necessaries of reconsidering the present structure of cropping pattern to increase the efficiency of irrigation water use.

A computer program based on windows application was developed using a Micro soft visual dot net software to determine the water requirements for vegetable crops in arid land. Through three simple steps, the user can easily calculate the water requirements for more than 35 vegetables. The first step is to locate the area of growing crops and compute the reference Evapotranspiration (ETref) using the Penman Monteith mathematical model. The second step is select the crop factor values and growing period lengths. Accordingly, the crop ET is calculated. The third step is to compute the total irrigation water requirements for the selected vegetable crop. It is intended in the paper to show all mathematical background used in the calculations. In addition, snap shot screens will be used to illustrate the use of the developed computer program.

The current study was carried out at the Agricultural and Veterinary Research Station, Faculty of Agriculture and Veterinary Medicine, Qassim University, Kingdom of Saudi Arabia during the two seasons 2003/2004 and 2003/2004. The objectives of this study are to investigate the effect of irrigation scheduling methods with different amounts of applied water on date palme offshoot growth, Determination offshoot consumptive use, crop coefficient, actual water requirements and the suitable soil moisture tension in the root zone before irrigation. The irrigation was scheduling by three methods, evapotranspiration calculation method, soil moisture depletion  method and farmer method (control). The evapotranspiration  calculation method (ETo) included ten treatments as a percentage of evapotranspiration (0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0 ETo). The soil moisture depletion method included five treatments of soil moisture depletion as a percentage of field capacity (50%Fc, 60%Fc, 70% Fc, 80% Fc and 90% Fc). The results showed that scheduling irrigation of the offshoot by evapotranspiration calculation method (ETo) or by soil moisture depletion  method, the amount of applied water decreased and the offshoot growth and the water use efficiency increased; compared with the farmer scheduling method. The daily and seasonal gross irrigation requirements for date palm offshoots were 51.3 l/day and 2191 m3/hec.year, while the farmer applied 19960 m3/h.year. So, the farmer added seven times as much as the actual gross irrigation requirements. The maximum water use efficiency were 2.5 kg/m3 and 1.44 kg/m3 for the treatments 0.1 ETo and 50% Fc, respectively. The suitable soil  moisture tension in the root zone before irrigation were 21.5  to 22 C-bar and 22.5 to 23 C-bar for 60 cm and 90 cm depths, respectively.