Establishment of Tissue Culture and Regeneration System in Hippophae gyantsensis Lian

Hippophae gyantsensis Lian is a pioneering tree species in Chinese forestry ecological engineering, known for its robust stress tolerance, water retention capacity, and soil improvement qualities. However, the lack of rapid nursery technology has been a significant impediment to the development of the H. gyantsensis industry. In the present study, we have successfully established a tissue culture regeneration system for H. gyantsensis. The most effective methods for seed disinfection, ensuring sterility in seedlings, were found to be 75% alcohol disinfection for 40 s and 10% sodium hypochlorite disinfection for 10 min. The best media tested for callus induction in cotyledons and hypocotyls of sterile seedlings were 1/3 MS + 0.5 mg/L KT + 0.75 mg/L NAA and 1/3 MS + 0.3 mg/L 6-BA + 1.5 mg/L IBA, respectively. As the explants, cotyledons yielded larger calli with a greater size and differentiation ability than hypocotyls. For the induction of indeterminate shoots and proliferation, the most suitable media were 1/3 MS + 0.5 mg/L IAA + 0.75 mg/L 6-BA and 1/3 MS + 1.0 mg/L 6-BA + 0.05 mg/L IBA + 0.1 mg/L KT, respectively. Lastly, the best worked rooting formulation was 1/4 MS + 0.3 mg/L IBA. This study marks a significant milestone in the establishment of a systematic tissue culture regeneration system for H. gyantsensis, which will facilitate the industrial rapid propagation of high-quality seedlings and provide the foundation for improvement through genetic transformation.