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Rapid and efficient propagation methods that avoid the use of mutagenic growth regulators are required for date palm breeding and cultivation. The effects of different growth regulators on micropropagation of six female cultivars of date palm including Barhee, Medjool, Khalas, Khadrawi, Nemeishi and River Gem and the male cultivar Jarvis were invstigated. The experiments were conducted in vitro using floral explants of female and male mature inflorescences. Embryogenic callus induction and proliferation were significantly higher (93%) in the woody plant nutrient culture medium (WPM) supplemented with 5mg l-1 Thidiazuron (TDZ). The addition of zeatin to the medium was most effective for shoot regeneration from callus and this enhanced regeneration frequency and the average number of shoots obtained per explant. The highest number of shoots/explant (16) was obtained using 2 mg l-1 zeatin in WPM and WPM with 0.5 mg l-1 GA 3 and 2 mg l-1 zeatin enhanced shoot length significantly. Bud initiation and adventitious shoot formation 16 weeks after flower culture was enhanced by WPM supplemented with 1.5 mg l-1 2,4-D and 5 mg l-1 2ip. Sub-culturing of formed buds on a multiplication medium supplemented with 3.0 mg l-1 zeatin and 0.3 mg l-1 NAA produced the highest average number of buds. Adventitious shoot elongation (up to 7.64 cm) was maximized using a WPM medium with 0.5 mg l-1 GA 3 and 3 mg l-1 zeatin. Optimum rooting (81%) was achieved when shoots were transferred to a medium with 0.2 mg l-1 NAA. The survival rate was 80% and the plants were subsequently transferred to bigger pots and acclimatized for field planting. No phenotypic differences were observed among the regenerants. This observation was validated using a set of five highly polymorphic iPBS and SSR markers.

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