Establishment of an efficient regeneration system for Lycium barbarum

Lycium barbarum , belonging to Solanaceae family, is a traditional "medicine and food homology" plant, with many beneficial effects, such as anti-oxidation and anti-aging. However, there are no protocols for its efficient regeneration system, which limit large-scale propagation and molecular breeding of L. barbarum . 6-BA (6-Benzylaminopurine), NAA (Naphthaleneacetic acid) and 2,4-D (2,4-Dichlorophenoxyacetic acid) are plant growth regulators commonly used in plant tissue culture, and they have important roles in the induction of healing tissues, adventitious root formation, and adventitious shoot induction. In the present study, we used L. barbarum stem segments as explants for tissue culture, which resulted in an efficient regeneration protocol. For this purpose, we evaluated the effects of different hormone combinations (6-BA and NAA) on callus induction and adventitious root formation. Under light condition, 100 % green callus from the stem segments of aseptic seedling was inducted with 0.1 mg/L 6-BA + 0.05 mg/L NAA and 0.1 mg/L 6-BA + 0.3 mg/L NAA treatments. We also observed the highest rooting ratio with 46.7 % in control group on initial medium, and then a large number of adventitious roots could be inducted with moderate supplementation of NAA. Finally, an efficient regeneration system was established on MS medium with 0.5 mg/L 6-BA + 0.2 mg/L 2, 4-D, and it could promote the white callus proliferation, differentiation and adventitious bud regeneration. Using this regeneration system, we achieved a one-step method to induce callus and adventitious bud differentiation, which has the characteristics of simplicity, shortening the time of obtaining regenerated plants, and improving the experimental efficiency. In conclusion, the results provide useful information and available protocols for large-scale propagation of L. barbarum , and its related species, which lay the foundation for further molecular breeding program . • The optimal hormone combinations for stem segments proliferation was found. • 100 % green callus was inducted on MS medium containing 0.1 mg/L 6-BA + 0.05 mg/L NAA and 0.1 mg/L 6-BA + 0.3 mg/L NAA. • The adventive bud successful induced on MS medium containing 0.5 mg/L 6-BA + 0.2 mg/L 2,4-D.