Effects of Plant Growth Regulators on Somatic Embryo Regeneration of Liriope spicata

Liriope spicata is an important traditional Chinese medicine and is also used as an ornamental groundcover plant. A tissue culture method, such as somatic embryo regeneration, that can generate large numbers of genetically identical plants would help maintain the characteristics of specific varieties. This study aimed to screen and optimize plant growth regulators for all aspects of somatic embryo regeneration in L. spicata. The plant growth regulators 2,4-dichlorophenoxyacetic acid (2,4-D), 6-benzylaminopurine (6-BA), naphthalene acetic acid (NAA), gibberellic acid (GA(3)), indole-3-acetic acid (IAA), and kinetin (KT) were screened in tissue culture media. We found that 2 mg/L 2,4-D + 2 mg/L 6-BA + 0.1 mg/L NAA had the best induction efficiency of 30.95%. During the screening of the somatic embryo proliferation media, we found that MS + 1 mg/L 6-BA + 0.1 mg/L NAA + 20 g/L glucose + 7 g/L agar, with a pH of 5.8, had the best proliferation efficiency of 86.67%. For the germination of somatic embryos, we found that MS + 0.1 mg/L 6-BA + 0.2 mg/L NAA + 1 mg/L GA(3) had the best effect, with an efficiency of 29.03%. Indole-3-butyric acid (IBA) had a significant effect on the induction of adventitious shoots, with the formula 1/2 MS + 0.1 mg/L IBA resulting in an efficiency of 100%. The establishment of the regeneration pathway for L. spicata somatic embryos not only ensures the industrial production of species but also provides reference for the application of plant growth regulators in plant tissue culture.