Germplasm preservation in vitro of Polygonum multifl orum Thunb

Background: The root of Polygonum multifl orum Thunb. is a common traditional Chinese medicine. In recent years, the wild resources of P. multifl orum have been seriously broken, and the cultivated varieties have been degrading. The germplasm resources of P. multifl orum need protection and preservation. So far, no in vitro germplasm preservation of P. multifl orum has been reported. Objective: To explore a method for the in vitro germplasm preservation of P. multifl orum. Materials and Methods: A large number of buds from seed explants were induced by tissue culture. The single buds were used as experimental materials to study the effects of plant growth regulator, temperature, and osmotic pressure on the preservation time, growth recovery, and genetic stability. Results: When the buds were inoculated onto Murashige and Skoog (MS) basal media containing 4% w/v sucrose, 2% w/v mannitol, and 1% w/v sorbitol, supplemented with paclobutrazol (PP333) 1.0 mg/l, abscisic acid (ABA) 5.0 mg/l, and daminozide (B9) 30.0 mg/l in an illuminated chamber under a 16 h photoperiod of 1500 lx light intensity at 15°C for 10 months, the survival rate was over 70% with good growth recovery and genetic stability. Conclusion: The results of this study can be used for medium-term in vitro germplasm preservation of P. multifl orum, and meeting actual needs of research and production.