The present study describes the role of different exogenous phytohormones, polyamines and sucrose on growth and rosmarinic acid (RA) production in whole plant culture of Solenostemon scutellarioides. It was further aimed to conserve elite clones via synthetic seed technology. S. scutellarioides was treated either singly or in combination with different phytohormones. Cultures incubated with NAA (0.5 mg L−1) yielded the highest RA accumulation (g−1FW), but negatively affected the growth. So, overall RA content was insignificant. Cultures incubated with IBA, BAP and GA3 at low concentration significantly improved growth and RA bioaccumulation. In the combinatorial study, IBA+BAP+GA3 (0.5 mg L−1 each) was found optimum for plant biomass and RA production (65.2% improvement of total RA). Amongst polyamines, putrescine (1 mg L−1) exhibited 20.4% improvement of total RA content. The intracellular RA accumulation (g−1FW) was significantly higher between 5 and 7% of sucrose concentrations. However, the total increase in RA content was inhibited due to deterioration of the culture with increasing sucrose concentration. Based on the effect of different treatments on growth and RA accumulation, a high yielding and stable plant line was selected for conservation via alginate encapsulation. Uniform shaped alginate coated synthetic seeds conserved up to 6 months exhibited high regeneration potential and RA content.
Synthetic seed technology for encapsulation and regrowth of in vitro-derived Acacia hyrid shoot and axillary buds