Abstract

The establishment of an efficient protocol for plantlets regeneration and micropropagation from leaf cultures of date palm cv. Quntar is reported. The two types of leaflet segments used in the experiment )First piece of leaf base which have white color, and second piece of leaf tip which have green color(, were taken from micro propagated shoots of date palm cv. These leaf segments were in vitro culture on MS media containing various concentrations of 2,4-dichlorophenoxyaceticacid at 1.0 mgl^-1 and benzyl adenine (BA). Maximum induction of callus was obtained from piece of leaf base (white) in medium supplemented with 5.0 mgl^-1 2,4-D and 1.0 mgl^-1 (BA), as compare with [piece of  leaf tip (green)[ which did not show response for callus formation. Using culture system with temporary tissue immersions "bioreactor" in  Somatic embryo production enriched with 1.0 mgl^-1 2,4-D + 500 mgl^-1 active charcoal (AC) gave the highest number of somatic embryos (172 embryos). These embryos formed from 500 mg initial callus. As well as, the short immersions frequently repeated, 1 min immersions every 4 h, led to the largest quantities of embryos. Indirect shoot organogenesis was achieved from the embryogenic callus using 3.0 mgl^-1 2iP + 1.0 mgl^-1 NAA, where highest number of shoots (8.28 ± 0.71) with maximum frequency (58.34%) was regenerated. The addition of 3 gml^-1 Gelrite to medium was optimal for the shoots proliferation. The balance of auxin to cytokinin in medium affected on the growth of the date palm tissue. The shoots were successfully rooted (80%) with rapid elongation when cultured on MS medium containing 0.5 mgl^-1 GA₃ + 1.0 mgl^-1 NAA. Rooted shoots were successfully acclimatized when planted in plastic pots containing a mixture of peat moss and perlite (2:1) with 80% success.

Key words: Date palm, histology, indirect shoot organogenesis, leaf segment, somatic embryogenesis, temporary immersion ‘bioreactor’.