SOMATIC EMBRYOGENESIS AND PLANT-REGENERATION IN A WOODY SPECIES - THEEUROPEAN SPINDLE TREE (EUONYMUS-EUROPAEUS L)

Somatic embryogenesis and subsequent plant regeneration of Euonymus eu ropaeus L (European Spindle Tree) were obtained from square pieces of mature zygotic embryos with an intervening callus phase. Callus and so matic embryos were induced using a Murashige and Skoog's semi-solid ba sal medium supplemented with several combinations of auxins and cytoki nins. The greatest number of somatic embryos was obtained with a conti nuous exposure to 22.8 muM indoleacetic acid and 0.046 muM kinetin. Th e frequency of somatic embryogenesis from zygotic embryos depends on t he cold conservation time of seeds. The embryos frequently germinated on the same medium. Further development of somatic embryos into plantl ets was achieved on a medium devoid of growth regulators.