Induction of Somatic Embryogenesis in Carrot by Osmotic Stress.

Abstract

Segments of cotyledon and apical tip taken from 1-week-old seedlings of Daucus carota L. were cultured for 3 weeks on hormone-free Murashige and Skoog's (MS) medium containing high amounts of sucrose (0.3-0.7M) and then transferred to the same medium with lower sucrose concentration (0.09M). Somatic embryos were formed from the segments 3 to 6 weeks after the transfer. On the other hand, hypocotyl segments given the same treatment did not produce somatic embryos. When the primary culture medium contained 0.61M mannitol and 0.09M sucrose, cotyledon segments and apical tip segments also produced somatic embryos when transferred to hormone-free MS medium with 0.09M sucrose. In all cases, somatic embryos were formed directly from the explants without visible callus formation.

Primary and secondary somatic embryogenesis in Chrysanthemum cv. Euro

“…Karami et al (2008) reported the highest secondary somatic embryogenesis was observed when combination of sucrose and mannitol was added to the culture medium. Previous reports on regulation of osmotic pressure in culture medium by mannitol have been done by many researchers (Robert 1991;Kamada et al 1993;Ikeda-Iwai et al 2002). Therefore, it would be interesting to study the influence of sucrose combined with an osmotic agent such as mannitol and/or of a sequential supply of high concentration.…”

Induction of somatic embryogenesis as an example of stress-related plant reactions

“…In carrot (Daucus carota), a model plant for SE, stress treatment on the PGR-free medium induces SE in the presence of different chemicals such as 0.7 M sucrose, 0.3 M NaCl or 0.6 mM CdCl Harada et al 1990;Kiyosue et al 1990;Kamada et al 1993).…”

Changes in Protein Pattern during Stress-induction of Carrot (Daucus carota L.) Somatic Embryogenesis.

“…3-A). [9][10][11][12]17]. These results indicate that these proteins may be directly related to induction of somatic embryogenic competence and/or early events of somatic embryo development prior to morphological differentiation of embryos rather than stress tolerance.…”

“…On the other hand, it has been reported that carrot somatic embryogenesis is induced by the treatments of apical tip segments with high concentrations of sucrose [8,9], NaCI [10] or heavy metal ions such as Cd2+ (Kiyosue et al, 1990) [11] in phytohormone-free medium. Futhermore, heat stress also induces somatic embryogenesis in phytohormone -free medium (Kamada et al, 1994) [12].…”