SOMATIC EMBRYOGENESIS IN SAINFOIN (Onobrychis viciifolia Scop.)

Sainfoin (Onobrychis viciifolia Scop.) is a perennial legume used for forage production. The aim of this study was to investigate the effects of different basal media (Murashige&Skoog-MS, Schenk& Hildebrant-SH, Gamborg-B5 or CHU-N6), explant types (cotyledon and hypocotyl), and growth regulators (kinetin and thidiazuron) on the induction of somatic embryogenesis in sainfoin. For this purpose, hypocotyl and cotyledon explants isolated from in vitro grown sterile seedlings were cultured in solid MS, SH, B5, or N6 basal media supplemented with 2 mg/L 2,4-dichlorophenoxyacetic acid, 0.2 mg/L kinetin or thidiazuron, and 1 g/L proline. The developing embryonic callus was then transferred to a solid MS medium containing 3% sucrose. As a result of the experiment, callus weights per explant varied between 248.3-534.7 mg, 408.7-609.1, 220.3-537 mg and 127.3-428.3 mg in MS, B5, N6, and SH basal media respectively, depending on explants and growth regulators. Average callus weights were higher in B5 and N6 basal media than in MS and SH media, TDZ-containing media than kinetin containing media and cotyledon explant than hypocotyl explant. The highest frequency of explants developing somatic embryos (mean 33.3%) was obtained from kinetin-containing MS or B5 basal media, while the highest embryo per explant (mean 2.6 somatic embryo per explant) was obtained from kinetin-containing MS medium. The somatic embryo number per hypocotyl explant was higher than that of cotyledon explants.