Three wheat genotypes (Triticum aestivum L.) namely Hashimia, Latifia and Tamooz were assessed for their salt tolerance in vitro. Calli were initiated on Murashige and Skoog (1962) basal medium supplemented with Kinetin 0.1 mg/l and 2,4-Dichlorophenoxyacetic acid (2,4-D) 1.0 mg/l using mature embryos as explants. One month old calli were inoculated onto a solid medium salinized with different concentrations of saline water obtained from drainage canals, Missan district, Iraq to make final concentrations of 0, 5, 7.5, 10, 12.5, 15, 17.5, and 20 ds.m-1. Results revealed that the three genotypes of wheat performed very well after subjection to screening and selection for salt tolerance program. The genotype Latifia seems gained more callus fresh weight and responded better than the others. Thus, it is a promising genotype for selection. This study also conducted a molecular marker based genetic analysis for the three genotypes expressing salt tolerance. The objective was to find molecular markers closely linked to the resistant genes that may be useful for gene cloning and improving salt tolerance in wheat breeding programs. To generate RAPD pattern, 8 primers were used to identify those that would be suitable for this purpose. Four primers showed clear amplification which was completely monomorphic bands. The DNA amplification pattern for Tamooz callus cultured on a medium salinized with 12.5 ds.m-1 exhibited genetic changes by using OPB7 primer.
Key words: Triticum aestivum L., callus, salt stress, RAPD, PCR
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