After inoculation of young leaves of date palm offshoot required about six months to complete the morphogenesis process. Fourteen weeks were required for embryogenic callus formation under continuous dark condition and nine weeks for shoot initiation (under 16/8 h light/dark). The highest number of explants (80%) produced callus in modified MS containing 5 mg/l 2,4-D + 2 mg/l 2ip. Sixty per cent of explants produced callus in the modified medium containing 5 mg/l 2,4-D + 5 mg/l NAA. While only

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... 0 per cent of the explants formed callus in the same medium when supplemented with only 5 mg/l 2,4-D. The induced calli were transferred to modified MS for shoot proliferation. A combination of two cytokines showed better performance than single ones in shoot induction. The highest percentage (70) of shoot developed in modified MS containing 2 mg/l BAP + 1 mg/l Kn. Forty per cent shoot induction was found in the same medium supplemented with 2 mg/l of BAP. Thirty per cent shoot formed in MS containing 1 mg/l of Kn. The shoots were subcultured at threefour week intervals throughout culture duration. 212 Kalam et al. References AI-Khalifah NS (2006) Micropropagation and DNA fingerprinting of date palm trees of Saudi Arabia. Aariena Pub. 1: 5-15. Al-Khayri JM (2001) Optimization of biotin and thiamine requirements for somatic embryogenesis of date palm (Phoenix dactylifera L.). In vitro Cell Dev. Biol. Plant. 37: 453-456. Al-Khayri JM (2002) Growth, proline accumulation, and ion content in Nacl-stressed callus cultures of date palm (Phoenix dactylifera L.). In vitro Cell Dev. Biol. Plant. 38: 79-82. Al-Khayri JM (2003) In vitro germination of somatic embryos in date palm: Effect of auxin concentration and strength of MS salts. Cur. Sci. 84: 101-104. Al-Khayri JM and Al-Bahrany AM (2001) Silver nitrate and 2-isopentyladenine promote somatic embryogenesis in date palm (Phoenix dactylifera L.). J. Sci Horti. 89: 291-298. Aslam J and Khan SA (2009) In vitro micropropagation of khalas' date palm (Phoenix dactylifera L.), an important fruit plant. J. Fruit Orna. Plant Res. 17: 15-27. Badawy EM, Afaf MA, Habib AEB and Yosry GM (2005) Propagation of date palm (Phoenix dactylifera) plants by using tissue culture technique. Arab J. Biotech. 8: 343-354. Baaziz M, Aissam F, Brakez Z, Bendiab K, Hadrami IE and Cheikh R (1994) Electrophoretic patterns of acid soluble proteins and active isoforms of peroxidase and polyphenoloxidase typifying calli and somatic embryos of two reputed date palm cultivars in Morocco. Euphytica 76: 159-168. Bekheet SA, Taha HS, Hanafy MS and Solliman ME (2008) Morphogenesis of Sexual Embryos of Date Palm Cultured In vitro and early identification of sex type. J. Appl. Sci. Res. 4: 345-352. Biroscikova MK, Spisakova, Liptak S and Pichler V (2004) Micropropagation of mature Wych elm (Ulmus glabra Huds.). Plant Cell Rep. 22: 640-644. Carpenter JB and Ream CL (1976) Date palm breeding, a review. Date Grow Inst. Rep. 53: 23-33. Chand S and Singh AJ (2004) In vitro shoot regeneration from cotyledonary node explants of a multipurpose leguminous tree, Pterocarpus marsupium roxb. In vitro Cell Dev. Biol. Plant. 40: 167-170.