Factors influencing efficiency of somatic embryogenesis of Gentiana kurroo (Royle) cell suspension

In this paper, we would like to show unexpected morphogenic potential of cell suspensions derived from seedling explants of Gentiana kurroo (Royle). Suspension cultures were established with the use of embryogenic callus derived from seedling explants (root, hypocotyl and cotyledons). Proembryogenic mass proliferated in liquid MS medium supplemented with 0.5 mg l⁻¹ 2,4-D and 1.0 mg l⁻¹ Kin. The highest growth coefficient was achieved for root derived cell suspensions. The microscopic analysis showed differences in aggregate structure depending on their size. To assess the embryogenic capability of the particular culture, 100 mg of cell aggregates was implanted on MS agar medium supplemented with Kin (0.0–2.0 mg l⁻¹), GA₃ (0.0–2.0 mg l⁻¹) and AS (80.0 mg l⁻¹). The highest number of somatic embryos was obtained for cotyledon-derived cell suspension on GA₃-free medium, but the best morphological quality of embryos was observed in the presence of 0.5–1.0 mg l⁻¹ Kin, 0.5 mg l⁻¹ GA₃ and 80.0 mg l⁻¹ AS. The morphogenic competence of cultures also depended on the size of the aggregate fraction and was lower when size of aggregates decreased. Flow cytometry analysis reveled luck of uniformity of regenerants derived from hypocotyl suspension and 100% of uniformity for cotyledon suspension.