Effects of plant growth regulator combinations on the growth of ginger (Zingiber officinale Roscoe) plantlets in vitro

The application of exogenous plant growth regulators (PGRs) alters the endogenous hormonal balance, thereby regulating key processes in plant tissue culture such as proliferation, rooting, and seedling production. Current research on ginger tissue culture predominantly focuses on the development of stage-specific culture media, tailored to particular phases such as proliferation or rooting. However, such narrowly optimized formulations often result in suboptimal efficiency when applied in scaled-up production systems. Therefore, it is imperative to devise integrated multifunctional media that can simultaneously support and enhance multiple developmental processes. This study used ginger shoot tips as explants and Murashige and Skoog (MS) basal medium in an orthogonal test design to investigate combinations of indole-3-butyric acid (IBA) and 6-benzylaminopurine (6-BA). The results showed that the optimal medium for Z. officinale tissue-cultured plantlets was MS + 0.25 mg·L -1 IBA + 1.25 mg·L -1 6-BA. This PGR combination resulted in the lowest browning rate (12.5%) and no hyperhydricity of isolated stem tips. Rooting coefficient (17.67), fresh weight (1.02 g), and leaf number (7.33) were significantly higher (P < 0.05) than other treatments. Additionally, shoot length (1.30 cm), multiplication coefficient (6.33), root length (1.48 cm), and plant height (3.67 cm) all ranked among the top performing groups. SOD activity (191.42 U·g -1 ) in this group was significantly higher than the overall mean, while MDA (1.29 μmol·mg -1 ) and H 2 O 2 (1.32 μmol·g -1 ) contents were lower than average values. This study provided a simple and rapid method for ginger tissue culture production, facilitating rational resource utilization and industrial application. • Developed a plant growth regulator combination for ginger plantlets in vitro. • The optimal media facilitates the ginger tissue culture process. • Enhanced the antioxidant capacity of cultured ginger plantlets. • Elevated exogenous cytokinin induces vitrification in ginger plantlets.