Somatic embryogenesis of tissue cultures of Papaver somniferum and Papaver orientale and its relationship to alkaloid and lipid metabolism.

Transfer from complete to 2,4-D free Gamborg's B5-medium efficiently induced somatic embryogenesis in Papaver tissue cultures (P. somniferum and P. orientale). Embryogenesis was preceded by a strong temporary accumulation of triacylglycerols. In both tissue cultures large amounts of sanguinarine type alkaloids were present, which disappeared during regeneration in the P. orientale cultures but persisted in the P. somniferum cultures. In the P. somniferum cultures protopine and morphine type alkaloids (morphine, codeine, thebaine) appeared about 45 days after exchanging the medium. Thebaine was the main alkaloid in the P. somniferum embryoids accumulating up to 0.2 % of dry weight.