The Effect of Picloram and Thidiazuron Concentrations on Prolif-eration Somatic Embryos from Immature Inflorescence of Date palm

Immature inflorescences of date palm(Phoenix dactylifer) cv.Sewi were used as explants for in vitro culture to investigate the effect of plant growth regulators oninflorescence proliferation. The inflorescences on initiation stage cultured on solidified Murashige and Skoog (MS) basal medium supplemented withPicloram 1, 5, 10 and 15 mg l-1 for two re-cultures. Then, transferred into medium supplemented with different concentrations of TDZ combined with NAA on proliferate stage. The optimal concentrations for successful inflorescence growth was 5 or 10 mg l-1 Picloram and through studying the residuals effect of Picloram on inflorescences proliferation in the presence of three concentrations of TDZ, it found that, 0.5 mg l-1 TDZ combined with 0.1 mg l-1 NAA was more effective to induce direct somatic embryos and gave the highest inflorescence proliferation percentage, while the high level of Picloram induced callus. Vegetative shoots formed into media containing 0.1 NAA mg l-1, 0.2 mg l-1 BA and 0.2 mg l-1 kin. All somatic embryos were converted successfully to healthy normal plantlets which could be transferred to greenhouse.