الفهرس 
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Abstract
This study mainly aims for genetic improvement in wheat to manage yield reduction under salinity, whereas wheat is the most important crop in Egypt, so that, we used biotechnology tools to create seawater tolerant wheat genotype( Misr 2). In addition, Optimization tissue culture and growth condition in wheat by immature embryo and contribute to existing knowledge by proposing a novel protocol for somatic embryogenesis in wheat where we elevate embryogenesis in wheat by adding different concentration of seawater in callus induction media. seawater in combination with auxin and cytokinin could activate endogenous ABA in somatic embryos that promoted maturation and accumulation of seed storage proteins. Removal of auxins from culture media was not necessary to release somatic embryos, The study reached a set of results, which can be summarized as follows: The concentration of 2 mgl-1 of 2, 4-D was optimum concentration in combination with 2 mgl-1 of NAA and hydrolatse Casein and high significant variation was found in mean of callus induction weight showed that Misr 2 is the best cultivar and CM2T is the best media, also plant regeneration resulted indicated that regeneration percentage of 25% for Misr 2 on RM1where it gave rise to many shoots (2 -4) per callus, Giza 168, Gemiza 9 developed greenish spots but did not regenerate to plants. Survey of embryo related genes expression patterns, plant hemoglobin gene expression indicate that the Hb1 transcript is primarily detected in all different stages of somatic embryogenesis development andHb1 transcript present at lower levels in ABA untreated calli .The expression level of Hb1 continuously increased during the growth stage of somatic embryogenesis, however the levels of expression de-creased during maturation stage of zygotic embryo. An expression level of Hb1 in somatic embryo (obtained by 50% sea water) is 16 - fold mature zygotic embryo and mature somatic embryo (obtained by ABA) and 32- fold in callus 50% salt treated. Expression level of Ta LEA gene in zygotic embryo was higher than its expression level in embryos obtained by both applied methods. In comparison with zygotic embryo expression pattern (standard for ideal maturation), embryos obtained by application of ABA had LAE expression level higher than (2- fold) embryos obtained by 50% sea water and TaWOX5 expression in somatic embryos was obtained by 50% sea water is higher than its expression level in both mature zygotic embryo and ABA somatic embryo. Relative expression of WOX5 gene in mature somatic embryos obtained by 50% sea water is higher 5 - fold its expression in mature zygotic embryo.