Callus induction and regeneration system establishment of Ajugae nipponensis / 中草药

ABSTRACT

Objective: An efficient and stable regeneration system of Ajugae nipponensis was developed by establishing the callus induction system and selecting the best protocol for higher plant regeneration. Methods: Stem tip, stem with buds, and inflorescence were all used as explants maintained on Murashige and Skoog (MS) medium supplemented with different types and concentration of plant growth regulator combinations. Results: Inflorescence was the optimal explant for callus induction and was cultured on MS medium containing 0.1 mg/L 6-BA and 1.5 mg/L 2, 4-D in 1 week; The callus divided into green multiple shoot 2 weeks later; The optimal medium for multiple shoot proliferation was MS + 2.0 mg/L 6-BA + 0.5 mg/L NAA, the regeneration rate of callus clustered buds was as high as 100%, the regeneration coefficient was 4.10, and the proliferation increased by more than five times after 4 weeks; The optimal medium for rooting was 1/2 MS + 1.0 mg/L NAA, the plant regeneration occurred 3 weeks later and the rooting rated up to 100%; Plantlet(100%) survived after transplanting rooted plantlets into sand. Conclusion: The callus can be induced by all kinds of explants and inflorescence is the best explant for higher callus induction rate; The current study lays a solid foundation for protecting the wild resources and advancing the cultivated of A. nipponensis, meanwhile providing scientific evidence for the research of genetic transformation.