الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
A field experiment was carried out at the experimental farm of Nuclear Research Center in 2014/2015 to investigate the effects of saline irrigation water on growth and yield of cultivated wheat crop and study the effect of organic mulching (rice straw mulch) under drip irrigation with emission uniformity (89.6%) on some properties of sandy soil, wheat production, water use efficiency, Nitrogen use Efficiency and water productivity. The aim of this study was studying the effect of saline water on wheat productivity in sandy soil under drip irrigation system, evaluating the effect of rice straw mulching as strategy on water use efficiency, studying the effect of rice straw mulching and irrigation water salinity on nitrogen use efficiency and nitrogen uptake using 15N tracer technique.
Control treatment was irrigated by fresh water, (F 0.5 dSm-1) and the two saline irrigation water were prepared by mixing fresh water with natural salt collected from (salt pans) to reach the desired concentration (S1 6 dSm-1) and (S2 8 dSm-1). Each treatment was irrigated twice a week using a total amount of 440 mm during the growing season with and without rice straw mulch.
The Neutron scattering technique used to detect the soil wettability during the growing season before and after irrigation measured at (30, 50, 70 and 90 cm soil depth). Nitrogen stable isotope 15N application used to detect added nitrogen in soil and evaluate the nitrogen uptake under salinity condition and effect of mulching on nitrogen use efficiency.
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SUMMARY AND CONCLUSION
Shaimaa K. EL-Tohory, (2016), M.Sc., Fac. Agric., Ain Shams Univ.
The data released from the recent study could be summarized as following:-
Plant height of wheat was measured in cm and the mulched treatments were higher than non-mulched.
Wheat yield for non-mulched treatment irrigated by fresh water (3366 kg ha-1) was higher than the mulched one irrigated with fresh water (3227 kg ha-1) and also higher than both mulched and non-mulched treatments irrigated with saline water of 6 and 8 dS m-1.
Under saline irrigation, wheat yield of mulched treatments were higher than the non-mulched ones for both 6 and 8 dS m-1.
Under non-mulched condition the treatment irrigated by 6 dS m-1 recorded a higher production of 2411 kg ha-1 than those irrigated by 8 dS m-1 (2231 kg ha-1). In the same sequence mulched treatment irrigated by 6 dS m-1 recorded higher yield (2936 kg ha-1) than the mulched one irrigated by 8 dS m-1 (2573 kg ha-1).
The harvest index in non-mulching treatments was much better than in mulching treatments. Thus the harvest index of wheat under mulching was decreased compering to non-mulched ones. This holds true with all irrigation water treatments.
Water use efficiency for non-mulched treatment irrigated by fresh water was higher than the mulched one .Under saline irrigation, water use efficiency of mulched treatments were higher than the non-mulched ones.
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SUMMARY AND CONCLUSION
Shaimaa K. EL-Tohory, (2016), M.Sc., Fac. Agric., Ain Shams Univ.
The nitrogen uptake by grain of wheat irrigated with fresh water and non-mulching treatments was much better than in mulching treatments. But, mulching treatment combined with saline water (6, 8 dSm-1) was much better than non-mulched one. Nitrogen uptake by shoots in mulching treatments was much better than in non-mulching treatments.
Soil salinity (ECe) increased with increasing the salinity of irrigation water under drip irrigation system. The value of electric conductivity under mulched soil was decreased, while it was increased under non-mulched soil. Salinity distribution in soil layer was changed along stages of growth and being more in non-mulched soil treatments.
Proportion and absolute values of Ndff as well as NUE gained by grains or shoot were severely reduced by increasing water salinity level as compared to those irrigated with fresh water. Mulching has a positive effect on combating salinity stress. It seems that, in general, mulching made the plants more able to derive more nitrogen from fertilizer and improved NUE. Nitrogen derived from fertilizer by grains was significantly higher than those of shoot. Similar trend was noticed for NUE.
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SUMMARY AND CONCLUSION
Shaimaa K. EL-Tohory, (2016), M.Sc., Fac. Agric., Ain Shams Univ.
Recommendation:-
1- Surface mulching could improve the growth and yield of wheat especially under saline irrigation by reducing soil evaporation and increase the wheat ability to combat salinity stress, where the reduction of yield for 6 and 8 dSm-1 are 13 and 24% respectively.
2- Using neutron scattering method save time and work and help to estimate soil moisture content and the actual evapotranspiration and drainage water.
3- Salts follow the direction of water movement so using drip irrigation system with saline water was effective especially with mulching.
4- Improving water efficient use with mulch under saline irrigation 6 and 8 dSm-1 and increasing 14 and 8 % respectively, may be due to reduction in evaporation and conservation of moisture for the crop.
5- Rice straw mulch is a cheap organic material and could be recommended as mulching.