Effects of culture medium composition on the <italic>in vitro</italic> growth of stem cuttings of <italic>Kirengeshoma koreana</italic> Nakai, a rare species in Korea

Abstract

Background and objective: <i>Kirengeshoma koreana</i> Nakai is an endemic and endangered species in South Korea. We conducted <i>in vitro</i> propagation and regeneration of <i>K. koreana</i> from stem cuttings to investigate the effects of nine different basal culture media and five different carbohydrate sources on its growth.Methods: Apical segments (at least 1 cm long) collected randomly from a six-week-old <i>K. koreana</i> plantlet grown <i>in vitro</i> were used as explants. In the first experiment, the explants were transferred into square vessels containing 50 mL of nine different basal culture media supplemented with 30 g⋅L<sup>-1</sup> sucrose and 3 g⋅L<sup>-1</sup> Phytagel. In the second experiment, the explants were transferred into square vessels containing 50 mL half-strength SH medium supplemented with five different carbohydrate sources at 30 g⋅L<sup>-1</sup>. Each medium was solidified with 3 g⋅L<sup>-1</sup> Phytagel. All experiments contained 4 cultures, and the experiments were repeated four times to enhance reproducibility. Data on stem length, shoot fresh weight, leaf width, leaf length, root count, and root length were collected at the end of 8 weeks of culture.Results: ANOVA showed that the basal culture medium had a significant effect on <i>K. koreana</i> growth (<i>p</i> < .001). The half-strength SH medium was the best condition for stem length, shoot fresh weight, leaf width and root length (3.76 ± 0.12 cm, 0.60 ± 0.06 g, 1.19 ± 0.05 cm, and 2.83 ± 0.13 cm, respectively). However, the highest percentage increase in root count (13.00 ± 0.90) was found to occur with half-strength WPM. The effect of different carbohydrate sources on <i>K. koreana</i> growth was significantly different (<i>p</i> < .001), with the exception of stem length and leaf width (<i>p</i> = .26 and <i>p</i> = .09, respectively). Maltose was the best condition for shoot fresh weight (0.90 ± 0.09 g). Although there was no significant difference, sucrose was found to be best for leaf width, leaf length and root length (1.34 ± 0.07 cm, 2.34 ± 0.10 cm, and 3.86 ± 0.19 cm, respectively).Conclusion: This <i>in vitro</i> propagation and regeneration system for <i>K. koreana</i> shows promise in terms of scalability and could help greatly with germplasm conservation and restoration efforts for the species.

Efficient In Vitro Propagation and Adventitious Shoot Organogenesis for the Conservation of Pseudolysimachion nakaianum (Ohwi) T.Yamaz., an Endemic Species in South Korea

“…Seeds of P. nakaianum were sourced from the Geumwon Mountains Forest Resources Management Office, Gyeongnam Institute of the Environment and Forest, Korea. Following a modified protocol outlined by Shin et al [9], the seeds were sterilized using several steps: immersion of seeds in 70% ethanol for 30 s followed by three rinses with sterile distilled water, then disinfection for 2 min in 1% sodium hypochlorite, and finally five rinses with sterile distilled water. For germination induction, the seeds were cultured in vitro on half-strength Murashige and Skoog (MS) medium [10], supplemented with 20 g L -1 sucrose and 3 g L -1 Gelrite ™ (Duchefa Biochemie, Haarlem, The Netherlands) as a solidifying agent in 100 × 25 mm Petri dishes.…”