Research on the rapid tissue breeding technology of the endangered plant Cibotium barometz (L.) J. Sm.

Cibotium barometz (L.) J. Sm., a fern, holds significant value in traditional Chinese medicine. This research aimed to establish a rapid tissue breeding technology for Cibotium barometz (L.) and provide a theoretical basis for its artificial breeding and industrial planting. The optimum conditions for spores germination were selected, including both the best sterilization time and the ideal spore germination medium. Subsequently, the optimal medium for proliferation and differentiation were chosen, and the optimal concentration of plant hormones was screened to determine the optimal medium. The rooting experiment was performed in two single-factor experiments by using differentiated sporophytes as materials. These experiments showed that the optimal sterilization time was 11 min and the best medium for germination was 1/8MS + 0.02 mg/L IAA. MS medium was suitable for proliferation, while WPM medium was suitable for sporophyte differentiation. The best medium for growth was MS + 1.0 mg/L IAA + 0.5 mg/L 6-BA. In the absence of sucrose, the seedlings barely grew and failed to differentiate into sporophytes. They showed optimal growth and differentiation at a sucrose concentration of 20 g/L. The plant growth regulators plant growth regulators used, including IAA, NAA, 6-BA, and GA₃, showed more effective differentiation, wherease KT had a slightly weaker effect. The rooting rate reached the maximum when the concentrations of ABT and IBA were at 1.5 mg•L^− 1 and IAA was at 1.0 mg•L^− 1. The IBA had a significant effect on the average and the longest root length, while the three PGRs had no obvious effect on the average or maximum diameter. Plant tissue culture seedlings still have good genetic stability after subsequent generation. In this study, the optimal cultivation conditions for rapid breeding technology in tissue culture, covering stages from germination and growth to differentiation and rooting, were obtained. Moreover, sporophytes were successfully transplanted to the external environment. This study provided a theoretical reference for the industrial planting of C. barometz.