Search Results (6)

The provincial-level registered superior cultivar Camellia chekiangoleosa ‘Ganhongyou 1’ boasts superior economic traits coupled with significant ornamental value, driving demand for an efficient propagation system. Consequently, this study aimed to develop a rapid micropropagation protocol by investigating culture conditions using semi-woody nodal segments with axillary buds as explants on Hyponex basal medium supplemented with varying combinations of plant growth regulators. Contamination was effectively minimized to 18% by a combined approach of surface sterilization (75% ethanol, 0.1% HgCl₂, and 20% NaClO) and incorporating 1 mL/L bactericide into the induction medium. For bud induction, the optimal medium was 2 g/L Hyponex supplemented with 1.0 mg/L 6-benzylaminopurine (6-BA) and 0.2 mg/L indole-3-acetic acid (IAA), achieving an 86.67% induction rate. The best proliferation was achieved on the medium containing 2 g/L Hyponex, 1.0 mg/L 6-BA, 0.15 mg/L 3-indolebutyric acid (IBA), and 0.5 mg/L gibberellic acid (GA₃), yielding a proliferation coefficient of 6.53. A combined strategy, integrating in vitro pre-culture with ex vitro treatment, proved most effective for rooting and acclimatization: shoots were first pre-cultured for 20 days on 1/2 strength Hyponex medium supplemented with 0.5 mg/L 1-naphthaleneacetic acid (NAA) and 2.0 mg/L IBA, followed by ex vitro base treatment with 1.0 g/L ABT (a rooting powder complex) solution before transplantation into seedling bags. This approach resulted in an 88% survival rate. Furthermore, anatomical analysis revealed the origin of adventitious root primordia from phloem parenchyma cells, thereby confirming a phloem-rooting pattern for this species. In conclusion, this study establishes a practical and efficient micropropagation protocol for ‘Ganhongyou 1’, providing a reliable technical foundation for its commercial-scale seedling production. Full article

Gastrochilus fuscopunctatus is a rare epiphytic orchid in Korea threatened by habitat loss and illegal collection. This study aimed to establish an efficient in vitro propagation system by evaluating asymbiotic germination and seedling growth. Mature seeds germinated on both Hyponex (Hy) and Orchid Seed Sowing Medium (OSM), but protocorm development was more active on Hy, regardless of 1 µM NAA supplementation. For seedling culture, Murashige and Skoog (MS), Hy, and Orchid Maintenance Medium (OM) were tested with apple homogenate (AH), banana homogenate (BH), and coconut water (CW). At 7 months, Hy supported the greatest biomass and root formation, while Hy + BH produced the highest values (0.066 g fresh weight, 1.3 cm root length). Although BH improved growth on MS and OM, the effects were less pronounced. At 14 months, Hy + BH again yielded superior results (1.93 g fresh weight, 5.3 cm root length, 17.2 leaves), clearly outperforming all other combinations. AH and CW showed inconsistent or limited effects across media, indicating strong medium–additive interactions. These findings demonstrate that Hy + BH is the most effective combination for both early and prolonged growth of G. fuscopunctatus, providing a practical framework for ex situ conservation and reintroduction. Full article

The orchid Dendrobium moniliforme faces endangerment due to habitat loss and illegal harvesting, necessitating the development of an optimized artificial propagation system to aid conservation and reintroduction efforts. This study evaluated the effects of three plant growth media, namely Murashige and Skoog (MS), Hyponex, and Orchid Maintenance Medium (OMM) (P668), and various organic additives (apple homogenate, banana homogenate, and coconut water) on the in vitro seedling growth of D. moniliforme. The results reveal that, in early postgermination stages, seedlings achieve maximum growth in the Hyponex medium, with a fresh weight (92 mg) and root length (2.7 cm) approximately 20-fold greater than those in the MS medium and OMM. After 6 months, for seedlings grown in MS medium and OMM with banana (50 g·L⁻¹), the mean fresh weights were 29 and 107 mg, respectively; however, the highest biomass was observed in seedlings grown in the Hyponex medium with coconut water (50 mL·L⁻¹), exhibiting a mean fresh weight of 201 mg. This study highlights Hyponex medium with coconut water as the most effective combination for promoting D. moniliforme growth and identifies suitable organic supplements for the in vitro cultivation of seedlings from asymbiotic seed culture. This propagation system offers valuable technical support for the mass production and conservation of this epiphytic orchid. Full article

Two prevalent issues with Gastrodia elata growing in a natural wild environment are the necessary symbiotic seed germination with Mycena spp. and the long growing cycle of protocorms into mature rhizomes with Armillaria mellea. This study explored the most suitable nutrients to germinate seeds and the developmental stages and propagated protocorm/juvenile rhizomes (jrhs) through a tissue culture approach. Adding humic acid, mashed potato, peptone, and (indole-3-acetic acid) IAA to the 2 g/L Hyponex 7-6-19 basal medium accelerated seed germination into protocorms with an average length of 2 mm. The nutrients best for the in vitro propagation of jrhs consisted of 1 g/L Hyponex 7-6-19 and MS salts with 1/2 NH₄NO₃ and KNO₃, 2 mg/L BA, 2 mg/L NAA, 2 g/L tryptone, 2 g/L glutamic acid, 1 g/L chitosan, 10 g/L apple puree, 20 g/L mashed potato, 100 mL/L coconut water, and 1.5 g/L A. mellea powder, at a pH level of 6. The maximum length and number of jrhs were 17.2 ± 0.8 mm and 76.6, respectively, in two subcultures. The in vitro propagation system started from seeds of G. elata can be employed as a potential method to propagate protocorm/jrhs for the cultivation of mature rhizomes from indoor or outdoor cultures. Full article

Sedirea japonica is becoming endangered, and even extinct, due to habitat destruction and illegal collection, and the development of an optimized artificial propagation system is necessary for its conservation and reintroduction. Thus, the effects of plant growth medium strength (Murashige and Skoog (MS) and Hyponex media) and the addition of activated charcoal (AC) and organic supplements on seedling growth of S. japonica were investigated through in vitro seed culture. The results showed that seedling growth was higher in half-strength (1/2) media than in full-strength media. After the addition of AC, the highest leaf area (2.14 cm²) was recorded in the seedlings grown in 1/2 Hyponex medium, and after the addition of organic supplements, root development increased regardless of the media type. Among the sixteen suitable media tested at later seedling growth stages, 1/2 MS medium with the addition of 0.6 g·L⁻¹ AC, 30 g·L⁻¹ banana homogenate and 10 g·L⁻¹ apple homogenate was generally effective in fresh weight (6.13 g) and root length (9.59 cm). We demonstrated which organic supplements are preferred for in vitro growth of seedlings developed from S. japonica protocorms by asymbiotic seed culture, which can be used for mass production and conservation of this rare epiphytic orchid. Full article

Paphiopedilum armeniacum is a rare orchid native to China with high ornamental value. The germination of P. armeniacum seeds is difficult, especially for the mature seeds, which is the major limitation for their large-scale reproduction. This study explored the reasons for seed germination inhibition from the aspects of the important plant endogenous hormone—abscisic acid (ABA). The major endogenous hormone contents of seeds were determined at different developmental stages. The ABA content was 5.8 ng/g in 73 days after pollination (DAP) for the immature seeds, peaked at 14.6 ng/g in 129 DAP seeds, and dropped to 2.6 ng/g in the late mature stage of the 150 DAP seeds. The reduction of ABA content in the mature seed suggests a possible contribution to the increased expression of CYP707A, an ABA catabolism gene. The germination rate of the immature seeds was reduced to 9% from 69% when 5 μg/mL ABA was added to the Hyponex N026 germination medium. The result showed that ABA can inhibit the germination of P. armeniacum immature seeds. However, for the heavily lignified mature seeds, reduction in endogenous ABA level does not result in an increase in the germination rate. Lignin accumulation in the seed coat imposes the physical dormancy for P. armeniacum. In summary, the germination of P. armeniacum is regulated by both ABA and lignin accumulation. Full article