Effect of vitamins and inorganic micronutrients on callus growth and somatic embryogenesis from leaves of chilli pepper

The effect of different vitamins and inorganic micronutrients on callus gro wth and the induction and proliferation of somatic embryos from young matur e, fully expanded leaves of chilli pepper ( Capsicum annuum L.) was investi gated. Explants were cultured on a solid Murashige and Skoog (MS) medium su pplemented with 8% (w/v) sucrose, 12.9 muM 6-benzyladenine, 9 muM 2,4-dichl orophenoxyacetic acid and 0.5 mg l(-1) thiamin.HCl in various combinations of eleven different vitamins. Alternatively, explants were cultured onto a solid medium containing MS macro- and micronutrients except for the salts o f Mn, Zn, I, Cu and Co which were added at either the standard MS concentra tion or at a tenfold increased (Cu, Co) or decreased (Mn, Zn, I) concentrat ion. The results indicated that somatic embryogenesis from pepper leaves is favoured by the addition of nicotinic acid to the culture medium and the i ncrease of copper concentration (an average induction of 70.2 globular embr yos/mm(2) of explant surface, 9.2% higher than control), without reducing e mbryo maturation and germination.