MORPHOLOGY AND CONVERSION ABILITY OF SOMATIC EMBRYOS IN LONG-TERM EMBRYOGENIC CALLUS-CULTURE OF PAPAVER-SOMNIFERUM

Callus and meristemoids were derived from immature seeds of Papaver so mniferum L. (1-22 days after flowering) on the MURASHIGE and SKOOG's m edium supplemented with 0.1-1 mg.l(-1) alpha-napthaleneacetic acid (NA A) and 0.05-0.1 mg.l(-1) kinetin (KIN). Somatic embryogenesis was indu ced from meristemoids, which maintained high capacity for production o f embryo-like structures on the medium without growth regulators for m ore than 3 years. Typical somatic embryos with root-shoot axes develop ed spontaneously via globular, heart-shaped and torpedo stages. They e xhibited rooting ability. Somatic embryos having incomplete or abnorma l morphology were also observed. Abnormal development occurred in glob ular stage (''cleavage'' and adventitious embryoid formation) or in gl obular-to-heart transition (stubby and ring-shaped cotyledons, thick e longated hypocotyls and variable number of cotyledons). Abnormal somat ic embryos did not develop into the plantlets. We suggest that these m orphological abnormalities which resulted from the influence of growth substances during culture induction together with longterm cultivatio n conditions were the reasons of low transition ability of somatic emb ryos into the plantlets.