Rapid in vitro propagation of elite female plants of Idesia polycarpa var. vestita Diels

Background: Idesia polycarpa var. vestita Diels is an oil-bearing woody plant of significant economic value. Aims: To accelerate the propagation of its elite germplasm, this study aimed to establish an efficient and stable in vitro rapid propagation system using one-year-old stem segments from elite plants. Methods: Young stem explants were disinfected with 75% ethanol for 40 s, followed by 0.1% HgCl2 for 6 min. MS or 1/2 MS served as basal media, and various combinations of plant growth regulators were tested for axillary bud induction, proliferation, and rooting. Results: The optimal disinfection protocol yielded a 38.10% survival rate. The best axillary bud induction medium was MS + 1.5 mg/L 6-BA + 0.05 mg/L NAA + 0.08 mg/L TDZ, achieving 100% induction. For proliferation, MS + 1.5 mg/L 6-BA + 0.06 mg/L NAA + 0.01 mg/L TDZ (proliferation coefficient 5.81) was optimal. Rooting was best with 1/2 MS + 0.3 mg/L IAA + 0.1 mg/L NAA (100% rooting, 14 roots/plant). Conclusions: This study established a reliable micropropagation system for Idesia polycarpa var. vestita, providing technical support for the efficient production of high-quality seedlings.