PROMOTING THE EMERGENCE ROOTS OF "SEWI" DATE PALM IN VITRO

Plant tissue culture technique has proven as a quick and sustainable way to provide large-scale propagation of true-to-type date palm (Phoenix dactylifera L.) plants. Rooting is the final culture stage for transffered to greenhouse acclimatization which is the prime concept of micro propagation system. A good rooting system is the prerequisite for survival of ex vitro grown plantlets in the open field which responsible to absorb water and nutrients from the soil. The present work discussed the effectiveness of culture media components (¼ , ½ , ¾ and full strength of both Murashige & Skoog (MS) and Schenk & Hildebrandt (SH) medium) and some plant growth regulators as Indole butyric acid (0, 0.5, 1.0, 2.0 mg l-1 IBA), Triacontanol at 0, 5, 10, 20 μg l-1 TRIA and combination of the best concentration of TRIA with Gibberellic acid (GA 3) at 0, 0.5 and 1.0 mg l-1 and control treatment (free TRIA and GA 3) on rooting of date palm cv. Sewi in vitro. Finally, the rooted plantlets which produced from all treatments in the last experiment (TRIA and GA 3 combinations) were transferred separately to greenhouse and planted in plastic pots filled with peat moss+vermiculite+perlite 2:l:l (v/v/v) to determine the survival percentage. The results showed that the root number and length were significantly affected by MS and SH medium salts strength. Referring to MS medium, The highest number and length of root (3 roots and 8 cm) were obtained with quarter salts strength MS medium. In case of SH medium, The highest number and length of root (4.5 roots and 6 cm) were obtained with full strength SH medium. Also the results showed that the root number and length were significantly affected by IBA, TRIA and the combination between TRIA & GA 3. In case of IBA, the highest number and length of root (6 roots and 8 cm) were obtained at 1.0 mg l −1 IBA. Whereas in case of TRIA, the highest numbers and length of root (20 roots and 5 cm) were obtained at 5 μg l −1 TRIA. Finally, the highest number and length of root (27 roots and 6.4 cm) and the highest shoot length (17.3 cm) were obtained at 5μg l −1 TRIA+1.0 mg l −1 GA 3. In acclimatization stage, the best survival percentage (90%) after three months was obtained with the use of TRIA at 5 μg l−1 in combination with GA3 at 1.0 mg l−1 in compare with the control whereas survival percentage was (50%).