Effect of vitamins and inorganic micronutrients on callus growth and somatic embryogenesis from young mature leaves of rose

The effect of different vitamins and inorganic micronutrients on callus gro wth and on the induction and proliferation of somatic embryos from young ma ture, fully expanded leaves of rose (Rosa hybrids L.) was investigated. Exp lants were cultured onto a solid Murashige and Skoog (MS) medium supplement ed with 3% (w/v) sucrose, 53.5 muM p-chlorophenoxyacetic acid, 4.6 muM Kine tin, and 0.5 mg L-1 thiamin. HCl in combination with either of eleven diffe rent vitamins. Alternatively, explants were cultured onto a solid medium co ntaining MS macro- and micronutrients except for the salts of manganese (Mn ), zinc (Zn), iodine (I), copper (Cu), and cobalt (Co), which were added at either the standard MS concentration or at a tenfold increased (Cu, Co) or decreased (Mn, Zn, I) concentration. Embryo maturation and germination too k place on a MS medium supplemented with 5.2 muM 6-benzyladenine and 5.7 mu M 3-indole-acetic acid. The results indicated that somatic embryogenesis fr om rose leaves was favored by the addition of nicotinic acid and cystein to the culture medium and the increase of Cu concentration, without reducing embryo maturation and germination.