CYTOMORPHOLOGICAL STUDIES ON SOMATIC EMBRYOGENESIS OF GENTIANA-TIBETICA (KING) AND G-CRUCIATA (L)

The process of plant regeneration via somatic embryogenesis of two gen tianas, Gentiana tibetica and G. cruciata was described. For this purp ose seedling explants were cultured on agar medium and later maintaine d in cell suspension. For callus initiation seedling explants like: co tyledons, hypocotyl and root were plated on a callus induction medium (CIM) composed of MS (1962), supplemented with 0.5 mg/l 2,4-D and 1.0 mg/l Kin. For the formation of cell suspension culture, embryogenic ca llus was transferred into liquid maintained medium (MM) composed of MS (1962), supplemented with 1.0 mg/l Dic + 0.1 mg/l NAA + 2.0 mg/l BAP + 80.0 mg/l SA. The conversion of somatic embryo into plantlets requir ed a new medium (ECM) based on MS (1962) mineral salts, supplemented w ith 0.5 mg/l GA(3) + 1.0 mg/l Kin + 0.5 mg/l NAA. For cytomorphologica l studies of particular stages of embryogenesis, specimens were staine d with dyes and reagents: 1. PAS reaction with leukofucsin, 2. Safrani n + fast green, 3. Erlich's hematoxylin.