Effect of Phloroglycinol and Different Planting Media on Rooting and Acclimatization Plantlets of Date Palm cv. Zaghloul

Abstract

Date palm plantlets cv. Zaghloul derived from somatic embryogenesis were used to investigate factors affecting rooting and subsequent survival in acclimatization. Rooting formation was affected by phloroglcionl (PG) level (20, 40 and 80 per liter) added to rooting medium. Rooting medium supplemented with 40 mg/1 PG was statistically the superior and exhibited the tallest and greatest numbers of rootlets per each plantlet in addition 20 mg/l PG was statistically more effective as compared to either control medium or medium provided with 80 mg/1 PG. Plantlets were transferred to greenhouse to study the effect of different mixtures of media on survival percentage the most suitable mixtures were peatmoss + sand at (3:1v:v); peatmoss + sand + vermiculit + perlite at ( 1:1:1:1 v:v); and peatmoss + perlite+vermiculite (1:1:1v:v) as they exhibited 100 %,75% and 75% survival planlets ( respectively) after three months of ex vitro acclimatization. The reverse was true with both peatmoss + sand (1:3 v:v ) and peatmoss+ perlite at 1:1 v:v where each one resulted the least survival percentage (25%). In addition the peatmoss + sand mixture at equal proportion 1:1 by volume was in between the aforesaid two extremes 50% after three months of ex vitro acclimatization. Key words: Rooting, acclimatization, in vitro, tissue culture, date palm IntroductionDate palm (Phoenix dactylifera L.) is a monocot and dioecious plant propagated vegetatively by off shoots production is limited in date palm depending on plant vigor and variety consequently clonal multiplication rate is slow (Pareek, 1984). These problems can be overcome by propagation through tissue culture.Adventitious rooting was obtained readily after reculturing separated shoots to rooting midum. However, an important problem encountered in date palm micropropagation, is acclimatization of plantlets. To overcome the acclimatization problems must be study the factors affect rooting formation. For this purpose we studied the effect of phloroglycnol on the rooting stage and consequently their survival in acclimatization stage.