Somatic embryogenesis induction and plant regeneration in date palm (Phoenix dactylifera L.) cv. Bouskri

Abstract

The effects of different medium components on somatic embryogenesis induction, and somatic embryo maturation and conversion were evaluated in date palm cv. Bouskri. Adventitious bud segments were used to induce somatic embryogenesis. The explants were cultured on Murashige and Skoog medium at full strength (MS) or half strength (MS/2), supplemented with two concentrations (10 or 20 mg/l) of either 1-naphthalene acetic acid (NAA), 2,4-dichlorophenoxyacetic acid (2,4-D) or indole-3-acetic acid (IAA). Somatic embryos were then cultured on either MS or MS/2 medium containing three concentrations (10, 30 or 50 g/l) of polyethylene glycol (PEG). Afterwards, the effects of gibberellic acid (GA3), polyvinylpyrrolidone (PVP) and activated charcoal on somatic embryo germination were evaluated. The findings revealed that the use of full-strength MS medium supplemented with 20 mg/l 2,4-D results in the highest callogenesis (100%) and somatic embryogenesis (70%) rates. For somatic embryo maturation, MS medium containing 30 g/l PEG gave the highest mean number (58.6) of mature somatic embryos per 100 mg fresh weight callus. On the other hand, it was found that the use of GA3 significantly increases the germination rate of mature embryos, while there was no significant difference between the effects of PVP and activated charcoal on somatic embryo germination. After transferring the plantlets to the glasshouse, the survival rate observed was 82.35%. The results of this study highlight the optimal medium components for each step of the somatic embryogenesis process of date palm cv. Bouskri, and could be used for mass propagation and genetic improvement purposes.

Keywords

• palmier dattier
• régulateurs de croissance
• callogenèse
• embryogenèse somatique
• régénération