Regeneration of diploid annual medics via direct somatic embryogenesis promoted by thidiazuron and benzylaminopurine

The development of a simple and rapid procedure for direct somatic embryoge nesis from wild Medicago spp. (M. truncatula, M. littoralis, M. murex, M. p olymorpha) has exploited various explants including meristematic zones. Phy togel-solidified medium supplemented with thidiazuron or 6-benzylaminopurin e at different concentrations effectively promoted this process. The first somatic structures emerged within 20 days of culture initiation. Histologic al analyses confirmed the nature of the directly formed embryos. Secondary embryogenesis was also observed. Cuttings of clusters of primary and second ary embryos were used for cyclic production of new embryo generations. Rege nerated plants with well-developed root systems on medium with reduced leve ls of macroelements and sucrose were easily adapted to a greenhouse.