Somatic embryogenesis-mediated plant regeneration of Eclipta alba (L.) Hassk. and its conservation through synthetic seed technology

Plant regeneration by means of somatic embryogenesis has been standardized for the first time in Eclipta alba (L.) Hassk. Explants like nodal segment, shoot tip, and leaf were tested on Murashige and Skoog medium supplemented with picloram, 2,4-dichlorophenoxyacetic acid, or α-naphthalene acetic acid for callus induction. Nodal segment exhibited the maximum response (92.80%) to callus induction on culture medium-containing 2.0 mg l−1 picloram. Furthermore, highest rate (88.40%) and number (34.83) of somatic embryo induction were found on medium fortified with 2.0 mg l−1 picloram, 0.5 mg l−1 thidiazuron, and 0.25 mg l−1 abscisic acid. Influence of abscisic acid on the somatic embryo regeneration was also tested with the highest frequency (95.50%) attained on medium-containing 0.75 mg l−1 N6-benzyladenine and 0.5 mg l−1 abscisic acid. Somatic embryo of torpedo stage was efficiently encapsulated with 2.5% sodium alginate and 75 mM calcium chloride, and exhibited 93.33% germination rate. The study revealed that storage at low temperature (8 °C) gave superior results where 86.67% of the synthetic seeds sprouted even after 60 days with a decline to 46.67% in 90 days post-storage. The rate of germination at 25 °C had been constantly low and failed to sprout after 75 days. The acclimatization of the regenerated plantlets was successfully taken place in garden soil, sand, and vermicompost in the ratio of 1:1:1 with 95% survival rate.