Adventitious Shoot Regeneration from Leaf Explants in Sinningia Hybrida 'Isa's Murmur'

As a valuable ornamental plant, Sinningia hybrida 'Isa's Murmur' (S. hybrida) has genetic flower diversity, which has great potential to develop different flower characters in the horticultural market. The present study focuses on establishing a practical approach for the sustainable propagation of S. hybrida. Compared with aseptic seeding leaves explants, field-grown leaves explants are more suitable for adventitious shoot regeneration. Adding 0.1 mg L^-1 NAA and 2.0 mg L^-1 TDZ could obtain the highest adventitious shoot proliferation coefficient (24.5), and the induction rate was 91.7%. The shoot proliferation coefficient (20.7) and the greatest shoot length and induction rate (95.3%) were achieved in 0.1 mg L^-1 NAA and 2.0 mg L^-1 BA medium, accompanied by rooting formation. Adding 0.5 mg L^-1 GA₃, 1.0 mg L^-1 BA, and 0.2 mg L^-1 IBA to MS medium can effectively prolong the regenerated buds for rooting. The best for rooting was 1/2 MS medium containing 0.3 mg L^-1 IBA, with the maximum number of roots (13.4 per shoot) and survival rate for transplanting (100%). This work aims to build an efficient, definitive, and scalable protocol for S. hybrida regeneration useful for large-scale cultivation and even more protoplast fusion and genetic transformation to develop more colorful or fragrant flowers.