Effects of growth regulators and types of culture media on somatic embryogenesis in date palm (Phoenix dactylifera L. cv. Degla Beida)

• Reduction of the production cycle via somatic embryogenesis.
• Amplification of the embryogenic callus formation.
• Improved quantitative and qualitative yields of somatic embryos.

In the present study, we aim to develop a complete production scheme for the propagation of Algerian date palm Phoenix dactylifera L. (cv. Degla Beïda) by somatic embryogenesis. The scheme consists of four main steps: induction of callus, multiplication of nodules on solid and liquid media, initiation of somatic embryogenesis in agitated liquid medium and maturation and germination of proembryos on solid media. Our results showed that hormonal treatments (10 mg/L 2,4-D, 1 mg/L BAP) and (50 mg/L 2,4-D, 1 mg/L BAP) combined with 300 and 1500 mg/L of activated charcoal, respectively, promoted initiation and multiplication of nodular calli on solid media. The best multiplication factor (9.75) was obtained from these calli when they were further cultivated in liquid medium containing 1 mg/L 2,4-D. Moreover, liquid medium without growth regulators promoted the development of relatively homogeneous embryogenic suspensions. The return to solid medium without growth regulators during the maturation phase improved the yield of somatic embryos and their subsequent germination.