الفهرس 
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Abstract
Eleven wheat (Triticum aestivum L.) genotypes were screened for salinity tolerance. Seeds were germinated under six salinity levels, i.e. 0, 6000, 9000, 10000, 11000 and 12000 ppm. Three genotypes, i.e. Sids 1, Sakha 8 and line 25 were selected for performing crosses. Three crosses were conducted between the selected genotypes, i.e. CrI (Sids 1 X Sakha 8), Cr.II (Sakha 8 X Line 25), and CrIII (Sakha 8 X Line 25). Their F1 plants were grown to obtain their anthers. Anther culture was used as a breeding technique to obtain pure lines in a short time. Great differences were observed in callus induction among the anthers of the three crosses. Embryogenic callus induction reached 10.1, 61.9 and 51.4 % for CrI, CrII and CrIII, respectively. Frequency of regenerated plants reached 1.4, 8.5, and 9.0 % for CrI, CrII and CrIII, respectively. Root tips of regenerated plants were cytologically examined to determine their ploidy level. All the examined plants were haploid type. Haploid plants were treated by colchicine for chromosome doubling. The doubled haploid plants reached 22.3, 24.4, and 22.1 % for CrI, CrII and CrIII, respectively. Number of double haploid plants reached 27, 225 and 203 for crosses CrI, CrII and CrIII, respectively. Eight double haploid lines were selected from each cross (depending on the available number of kernels) were tested for salinity tolerance in addition to 8 Egyptian genotypes i.e., Sids 1, Sakha 8, line 25, Gemmeza 10, Gemmeza 9, Giza 168, Sakha 94 and Sakha 93 as references under different salinity levels (tap water, 6000 and 12000 ppm) in pots. Various morphological characters and chemical constituents were estimated for two vegetative growth stages as well as yield and its components. Lines CrI-L1, CrI-L2, CrI-L3, CrI-L4, CrII-L4 and CrIII-L.6 were the highest salt tolerant over all tested genotypes in all estimated parameters.