الفهرس 
Line-Source Sprinkler Irrigation System:Only 14 pages are availabe for public view
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Abstract
Esam Mohamed Habib: Evaluation of Some Wheat Genetic Resources to Drought Tolerance under Sandy Soil Conditions. Unpublished Ph.D. Thesis, Department of Agronomy, Faculty of Agriculture, Ain Shams University, 2011 br Two field experiments were carried out in newly reclaimed sandy soil at El-Bustan Experimental Research Station, South Tahrir, Behaira Governorate, during 2005/2006 and 2006/2007 growing seasons to evaluate the performance, water use efficiency and yielding ability of twelve bread wheat genotypes in the newly reclaimed sandy soil under diverse water stress conditions. br Twelve genotypes of bread wheat (Triticum aestivum L.) that evaluated comprised four commercial cultivars; Sakha 94 (as new and high yielding cultivar), Yacora (highly drought tolerant cultivar), Giza 168 - Sakha 93 (as widespread cultivars in El-Bustan region), besides four promising lines (2 -#102;-#114;-#111;-#109; Egypt and 2 -#102;-#114;-#111;-#109; Sudan) and four landraces collected -#102;-#114;-#111;-#109; diverse areas of Egypt. br Water stress treatments were carried out under line-source sprinkler irrigation system to impose four water stress treatments plus well-watered (about 100% well-watered, 80%, 60%, 40% and 20% of well-watered) to evaluate wheat genotypes and identify the best economic irrigation level. br A split-plot design with four replicates was used in the both seasons, water stress treatments arranged as main plots and wheat genotypes were randomly distributed in sub-plots. br The results indicated that genotypes # 7 - 10 gave the highest grain yield under different water stress levels as compared to remained genotypes under study, the water use efficiency (WUE) of these two genotypes was the highest (1.10 and 1.02 kg grains/m3, respectively) compared to different wheat genotypes, and surpassed the new high yielding variety Sakha 94 (# 1) that recorded WUE value of 0.97 kg/m3. br As well as, these two genotypes # 7 and 10, recorded the lowest values of drought susceptibility index (DSI) being 0.82 and 0.84, respectively, this means that these two genotypes considered to be the highest drought tolerant than any other genotypes, because they exhibited smaller yield reduction under drought stress conditions, while the new high yielding variety Sakha 94 (# 1) that recorded 1.07 of DSI was considered a sensitive genotype to drought stress conditions. br -#102;-#114;-#111;-#109; different yield components data, it could be concluded that wheat genotypes # 7 - 10 were characterized by the highest yield attributes, i.e., plant height, spikes number/m2, kernels number/spike, 1000-kernels weight, kernels weight/spike and spike length. It means that the genetic makeup of these two genotypes was adapted to grow under the adverse environmental conditions of new reclaimed sandy soils. br It could be concluded that with planting newly reclaimed sandy soils by the promising drought tolerant and high yielding genotypes (as genotypes # 7 - 10), it could be attain more wheat grain yields and save large quantities of irrigation water with the minimum lower reduction of wheat grain yield, which under a level of 80% water regime, relative decrease in grain yield for genotypes # 7 - 10 was about 6% only whereas WUE increased by about 16%, consequently, it could be saving about 20% of irrigation water. br Also, in case of necessity, under a level of 60% water regime (in lands with limited water resources and/or low rainfall), the relative decrease in grain yield for promising drought tolerant and high yielding genotypes # 7 - 10 was about 19% only whereas WUE increased by 32%, consequently, it could be saving about 40% of irrigation water to planting more newly reclaimed sandy soils that suffered -#102;-#114;-#111;-#109; water stress and adverse environmental conditions. br It could be recommended with the importance of exploitation of these two promising drought tolerant and high yielding genotypes # 7 - 10 to planting more newly reclaimed sandy soils that suffered -#102;-#114;-#111;-#109; water stress conditions, and utilization of these two genotypes in different wheat breeding programs for high yielding productivity and drought tolerance. br Key words: wheat genotypes, landraces, water stress, drought stress, water scarcity, line-source sprinkler irrigation system, newly reclaimed sandy soils, water use efficiency WUE, drought susceptibility index DSI.