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.
21 November 2023 in Conservation Genetics Resources
Koreanohadra koreana (K. koreana) is an endemic species in South Korea that is listed as endangered. While the ecology and phylogenetics of K. koreana have been studied, its morphological similarity to the related species Koreanohadra kurodana (K. kurodana), can make species identification difficult. Furthermore, this has led to confusion when determining essential habitat information for the conservation of K. koreana. To bypass this issue, we have developed a non-invasive species identification method that can genetically differentiate between them. While there are already various non-invasive genomic DNA (gDNA) extraction methods that utilize the mucus from mollusks, they are limited as they require the target species to be physically located. To address this, in this investigation a method of extracting gDNA from the feces of snails was developed. The method utilized a primer set to amplify a cytochrome b fragment from K. koreana but not K. kurodana or other terrestrial snails. The feces of terrestrial snails could thus be used to obtain gDNA to a genetically usable level if collected within 5 days of excretion. This non-invasive species identification method using feces will help to facilitate genetic research without harming the endangered species and if the target species is not physically in the habitat. Moreover, K. koreana and K. kurodana could perhaps be further distinguished, using their habitat information to help facilitate essential conservation measures.
Pedicularis hallaisanensis Hurusawa, native to Mt. Halla and Gaya, is an endangered endemic species. To support conservation efforts, this study investigated its germination characteristics and kind of seed dormancy. The seeds of P. hallaisanensis had fully developed linear embryos at dispersal, with no additional embryo growth observed. Water imbibition was observed prior to germination. The seeds were water-permeable. The seeds did not germinate at four temperature treatments (4 °C/1 °C, 15 °C/6 °C, 20 °C/10 °C, and 25 °C/15 °C). However, cold stratification and gibberellic acid treatments broke seed dormancy. Total germination was 15%, 15%, and 45% at 12, 16, and 20 weeks of cold stratification, respectively. Total germination at 25 °C /15 °C for GA treatments were 0%, 25%, 25%, and 80% at 500, 1000, 1500, and 2000 mg/L, respectively. This study showed that the seeds of P. hallaisanensis have intermediate physiological dormancy, requiring 20 weeks of cold stratification or more than 2000 mg/L GA concentration to maximize total germination. These results are useful for understanding ecophysiological mechanisms related to the species’ habitat and for mass propagation to conserve this endangered species.
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.
Calanthe aristulifera is an endangered terrestrial orchid that has historically suffered from severe illegal poaching. However, little is understood regarding population dynamics for remaining C. aristulifera populations. This study presented the first record on the size, reproduction rate, and insect visitors of C. aristulifera populations on an oceanic island from 2021 to 2025, to identify threatening factors and provide conservation implications. Throughout the study period, complete absence of fruit set of C. aristulifera was found (natural fruit set ratio: 0%). This reflects the reproductive failure as an on-going threatening factor, regardless of the yearly variations in total number of C. aristulifera individuals (198–253) and flowering rate (62.2–87.4%). The known pollinators (Eucera nipponensis and Lasioglossum occidens) were undetected near C. aristulifera populations, which coincided with complete reproductive failure. Insects like Callipora lata, Episyrphus balteatus, and Bibio tenebrosus visited to C. aristulifera flowers, but direct field and photographic observations showed no pollinia removal by such insects. Overall results highlight that conservation programs should adopt management practices to attract effective pollinators to C. aristulifera populations. Ex situ conservation may also be an option to facilitate in vitro propagation experiments, and help the remaining C. aristulifera to avoid severe reproductive constraints.
This study investigates the reintroduction and ecological adaptation of the endangered dung beetle, Gymnopleurus mopsus, in South Korea, a region from which it has been absent since the 1970s. To facilitate this, we imported genetically identical populations of G. mopsus from Mongolia and embarked on a comprehensive restoration research project. A key focus of this endeavor was to evaluate the adaptability of these beetles to the local environment, an essential aspect of successful reintegration of species from foreign ecosystems. Under meticulously controlled field cage conditions, we conducted an in-depth monitoring of the life history traits of G. mopsus. This monitoring revealed that the adult beetles, which entered hibernation in September 2019, began emerging in stages from late April to May 2020. Following hibernation, we observed that the adults engaged in reproductive activities from late-May until early-August, with the emergence of the first-generation (F1) adults occurring from late-July to mid-September. This led to a notable tripling in population size, increasing from 34 to 109 individuals. The successful survival and reproductive behaviors of these Mongolian dung beetles in the climatic conditions of Korea suggest a promising potential for their adaptation when reintroduced into native habitats. We are now directing our efforts towards long-term monitoring, focusing on the survival and reproductive efficacy of these new generations, to further validate the success of this ecological restoration project.