Establishment of an efficient and rapid artificial propagation system for Codonopsis pilosula

Abstract

[Objective] The study aims to explore the in vitro regeneration condition of Codonopsis pilosula (Franch.) Nannf. and establish an efficient and rapid propagation system to provide a basis for its seedling breeding. [Methods] The callus was induced by stem tips and stem segments in different hormone combinations, and then the L16 (45) orthogonal experiment was carried out with coconut juice, 6-BA, NAA, and KT to screen the best explant and the differentiation and proliferation medium for adventitious buds. Finally, the rooting and acclimatization of plantlets were realized outside the bottle. [Results] (1) The callus induction rate of the stem segments in MS medium with 6-BA of 1.5 mg/L and NAA of 0.5 mg/L was up to 98.76%, while that of the tips was only 76.56%. (2) Coconut juice had a significant effect on the proliferation of C. pilosula, and the proliferation coefficient reached 43.39 in MS medium with 60 mL/L coconut juice, 1.5 mg/L 6-BA, 0.5 mg/L KT, and 0.5 mg/L NAA. (3) The rooting rate of the regenerated buds in bottles was low, but the regenerated buds formed roots outside the bottle after 30 days, with a rooting rate of 87.96%. The survival rate after transplanting was 97.73%. In addition, the basal stem cluster buds and axillary buds appeared during callus induction and differentiation, which greatly improved the proliferation coefficient of C. pilosula. [Conclusion] The stem segment is more suitable for callus induction. Coconut juice promotes callus redifferentiation. Rooting outside the bottle significantly improves rooting rate.

Keywords

• codonopsis pilosula
• adventitious bud of callus
• coconut juice
• rooting outside the bottle
• in vitro rapid propagation