Papaver somniferum regeneration by somatic embryogenesis and shoot organogenesis

Secondary somatic embryogenesis and shoot organogenesis from primary somatic embryos of Papaver somniferum L. are described. The embryos became malformed, the root meristem expressed dividing activity without position-dependent cell differentiation, causing abnormal development or arrested growth of primary somatic embryos. The adventitious shoots regenerated from embryo hypocotyl, but secondary somatic embryos had an epidermal origin close to the root meristem. The regeneration occurred without hormonal treatment, indicating endogenous nature of triggering signals. These signals are probably related to the integrity loss of morphogenetic steps during development of primary somatic embryos, which appeared to induce an activation of cells competent to regeneration. This revised version was published online in August 2006 with corrections to the Cover Date.