AN EFFICIENT NOVEL PATHWAY DISCOVERED IN DATE PALM MICROPROPAGATION
Direct somatic embryos of date palm (Phoenix dactylifera L. Medjool) spontaneously developed on the individually proliferated axillary buds. Axillary bud proliferation occurred from shoot tips explants under dark condition afters 3 recultures on modified MS (Murashige and Skoog, 1962) medium supplemented with 2iP (1.0 mg/L), Kin (1.0 mg/L), BA (1.0 mg/L), NOA (0.5 mg/L) and solidified with gelrite (2.0 g/L). When buds were transferred under light conditions onto the same medium containing putrescine (150 mg/L), some of them (55.56%) showed direct embryos formation (3.78) at the surface of the buds after 8 weeks of culture incubation. When these embryos were soon removed after they became visible, they survived by transferring to a fresh medium, whereas they were destroyed if left intact with the bud. Embryos cultured on the previous medium omitting BA in addition to putrescine (100 mg/L) recorded the highest significant values of multiplication rate and growth value after 6 weeks of incubation. Individual shoots cultured on basal MS medium in addition to IBA (1.0 mg/L), sucrose (30 g/L) and solidified with phyto-agar (6.0 g/L) recorded the highest significant values of roots number and roots length after 8 weeks of incubation. Finally, using a mixture containing compost and perlite (1:1, v/v) recorded the highest significant percentage values of plantlets survival (80%) and number of leaves/plantlet (3.67) as well as the highest values of leaf length (17.1 cm) after 3 months in acclimatization. Phenotypically, plantlets showed similarity in the greenhouse.
Hegazy, A.E. and Aboshama, H.M. (2010). AN EFFICIENT NOVEL PATHWAY DISCOVERED IN DATE PALM MICROPROPAGATION. Acta Hortic. 882, 167-176
Phoenix dactylifera L., in vitro, direct embryogenesis, polyamines (PAs)