0000000000230633
AUTHOR
N. Béranger-novat
Ultrastructural Studies on Development in Mature Seeds; Embryos ofEuonymus europaeaL. Dormant or Cultured at +25 °C
Ultrastructural observations on naturally dispersed and dehydrated seeds of Euonymus europaea L. were performed. It was shown that during the culture of isolated embryos at 25 °C for 7 d the maturation of protein bodies continued; the initial juvenile form (single protein body per cell with dispersed contents) was developing into a more advanced form (single body split to form several sub-units with condensed contents). Parallel biochemical determinations pointed to an increase in insoluble protein levels. There were no changes in other storage organelles, lipid bodies, either in the fine structure or in the level of triacylglycerols. Deterioration of cellular membranes (in mitochondria, pr…
Stimulation of root and somatic embryo production in Euconymus europaeus L. by an inhibitor of polyamine biosynthesis
In vitro formation of roots and somatic embryos is obtained from cotyledon explants of a Spindle tree (Euonymus europaeus L.) cultured on two different media: a medium inducing callus formation and the production of roots, and a medium inducing callus formation, root and somatic embryo production. We studied the effects of α-difluoromethylornithine (DFMO), a specific, irreversible inhibitor of ornithine decarboxylase (ODC) on root and somatic embryo production, growth and titers of putrescine in Euonymus explants and explant-derived calli. Early changes in putrescine levels were detected in both cultures before the visible emergence of roots or somatic embryos. DFMO rapidly inhibited putres…
Effect of Gibberellin on Mature Euonymus europaeus L. Seeds
The release from dormancy of Euonymus europaeus L. embryos by a brief treatment with GA 3 has been studied. During 48 h incubation of dormant embryos in GA-free medium, phospholipid levels increased at first, then declined sharply over the last 6 h. When the embryos were placed in GA, medium during this 6 h period levels of total phospholipids as well as of phosphatidylethanolamine increased whilst phosphatidylinositol and phosphatidylcholine declined slightly
Somatic embryogenesis and plant regeneration in a woody species: the European Spindle Tree (Euonymus europaeus L.).
Somatic embryogenesis and subsequent plant regeneration of Euonymus europaeus L (European Spindle Tree) were obtained from square pieces of mature zygotic embryos with an intervening callus phase. Callus and somatic embryos were induced using a Murashige and Skoog's semi-solid basal medium supplemented with several combinations of auxins and cytokinins. The greatest number of somatic embryos was obtained with a continuous exposure to 22.8 μM indoleacetic acid and 0.046 μM kinetin. The frequency of somatic embryogenesis from zygotic embryos depends on the cold conservation time of seeds. The embryos frequently germinated on the same medium. Further development of somatic embryos into plantle…