Induction and Enlargement of Bulblets in Lilium brownii var. viridulum In Vitro

Lilium brownii var. viridulum is a popular natural health product that combines medicine and food. However, the lack of high-quality and efficient propagation technology has been a significant impediment to the development of the L. brownii var. viridulum industry. In this study, bulb scales of L. brownii var. viridulum were used as materials to investigate the induction of bulblets from scales, as well as the proliferation and enlargement of the induced bulblets. An in vitro regeneration system for L. brownii var. viridulum was successfully established. The most effective methods for scale disinfection were found to be 75% alcohol disinfection for 30 s and 10% Sodium Hypochlorite (NaClO) disinfection for 15 min. The recommended medium for scale differentiation was Murashige and Skoog (MS) + 0.05 mg·L−1 1-Naphthaleneacetic acid (NAA) + 0.25 mg·L−1 Thidiazuron (TDZ) + 0.05 mg·L−1 kinetin (KIN) + 30 g·L−1 sucrose + 6 g·L−1 Activated Charcoal (AC). The recommended medium for bulblet proliferation was MS + 1.5 mg·L−1 6-benzylaminopurine (6-BA) + 0.5 mg·L−1 NAA + 30 g·L−1 sucrose. The recommended medium for bulblet enlargement was Modified MS Medium (potassium dihydrogen phosphate (KH2PO4, KDP) doubled) + 90 g·L−1 sucrose. Bulblets with diameters of 1.5 cm were transplanted, and the germination rate was 100%. This study established a systematic in vitro regeneration system for L. brownii var. viridulum, which will provide the foundation for industrial production of L. brownii var. viridulum bulbs and improvement through genetic transformation.