Effect of Propagation Media and Plant Growth Regulators on Adventitious Rooting of Softwood Cuttings of Apocynum lancifolium Russanov

Effect of Propagation Media and Plant Growth Regulators on Adventitious Rooting of Softwood Cuttings of Apocynum lancifolium Russanov

Background and objective: Apocynum lancifolium Russanov is a perennial herb native to Korea and belonging to the familyApocynaceae. Herein, cutting mediums and plant growth regulators (PGRs) were examined to investigate the requirementsfor the cutting propagation of A. lancifolium. Methods: The study was conducted over a period of 6 weeks from May to June 2023. As types of cutting medium forpropagation by cutting, Kanuma soil, commercial potting mixes, perlite, and peat moss were used, and the PGRs ofindole-3-butyric acid (IBA) at varying concentrations (100, 500, and 1,000 mg·L-1) and a 1:1 (v/v) solution of Rootone(0.4% 1-naphthylacetamide) diluted in water were applied for this study. After six weeks, growth characteristics, includingcutting survival rate, rooting rate, shoot height, the number of leaves, root length, the number of roots, dry weight ofshoots, and dry weight of roots, were examined. Results: Among the different growing substrates used for experimentation, the cutting survival rate on Kanuma soil (81.7 ±5.0%) was the highest, followed by commercial potting mixes (40.0 ± 7.2%) and perlite (66.7 ± 2.7%), while the lowestcutting survival rate was on peat moss (35.0 ± 6.3%). On treatment with Kanuma soil (81.7 ± 5.0%), the rooting rate wasalso significantly greater than that when treated with other substrates. In the PGR experiment, the cutting survival rate androoting rate treated with Rootone (0.4% 1-naphthylacetamide) were significantly higher than those when treated withother substrates. Further, the number of roots increased with an increase in the IBA concentration. Based on the results,we recommend treating A. lancifolium cuttings with Rootone and Kanuma soil to ensure successful cutting propagation ofA. lancifolium. Conclusion: This mass production system for A. lancifolium via cutting propagation shows promise in terms of scalabilityand could help with germplasm conservation efforts for A. lancifolium.