Search Results (59)

Botanical gardens serve as vital centers for ex situ conservation, maintaining diverse plant species under controlled conditions. Terrestrial orchids, despite their wide diversity and distribution, often occur in small and declining populations, making their conservation increasingly urgent. This study aimed to examine the potential for establishing the first specialized orchidarium in Serbia, focusing on the native orchid species of the Fruška Gora region. A SWOT analysis, combined with site assessment data, was employed to identify key strengths, weaknesses, opportunities, and threats, informing the development of a functional zoning plan. The results indicate that such an orchidarium would offer a threefold benefit: strengthening ex situ conservation, advancing scientific research and environmental education, and promoting sustainable tourism. The proposed design consists of eight distinct zones, three of which reflect natural habitats of selected orchid species. The planned integration of a seed gene bank in the central zone, along with living plant collections and a nearby in vitro culture laboratory, establishes a comprehensive framework for the sustainable management of orchid genetic resources in the region, forming a foundation for future research and preservation. Full article

An efficient in vitro propagation protocol for Eulophia bicallosa was developed using asymbiotic seed germination and protocorm proliferation. The effect of light on seed germination and development was evaluated on Vacin and Went (VW) medium under five conditions: darkness, white, green, red, and blue light for 24 weeks. Blue and red light significantly accelerated seed development, allowing progression to stage 5 within 24 weeks. For protocorm proliferation, six semi-solid culture media were tested. Half-strength Murashige and Skoog (½MS) medium yielded the best results after 8 weeks, producing the highest numbers of shoots (1.0), leaves (1.1), and roots (4.2) per protocorm, with 100% survival. The effects of organic additives were also evaluated using coconut water and potato extract. A combination of 200 mL L⁻¹ coconut water and 50 g L⁻¹ potato extract enhanced shoot formation (1.7 shoots), while 150 mL L⁻¹ coconut water with 50 g L⁻¹ potato extract increased both leaf (1.9) and root (8.8) numbers. The effects of cytokinins (benzyladenine (BA), kinetin (6-furfurylaminopurine), and thidiazuron (TDZ)) and auxins (indole-3-acetic acid (IAA), α-naphthalene acetic acid (NAA), indole-3-butyric acid (IBA), and 2,4-dichlorophenoxyacetic acid (2,4-D)) were investigated using ½MS medium supplemented with each plant growth regulator individually at concentrations of 0, 0.1, 0.5, 1.0, and 2.0 mg L⁻¹. Among the cytokinins, 0.1 mg L⁻¹ BA produced the highest survival rate (96%), while 1.0 mg L⁻¹ BA induced the greatest shoot formation (93%, 2.3 shoots). Among the auxins, 0.1 mg L⁻¹ IAA resulted in the highest survival (96%), and 1.0 mg L⁻¹ IAA significantly enhanced root induction (4.2 roots per protocorm). Acclimatization in pots containing a 1:1:1 (v/v) mixture of pumice, sand, and soil resulted in 100% survival. This protocol provides a reliable and effective approach for the mass propagation and ex situ conservation of E. bicallosa. Full article

Background/Objectives: Changnienia amoena is a rare and endangered terrestrial orchid endemic to China, valued for its ornamental and medicinal properties. However, limited genomic resources hinder its effective conservation strategies and sustainable utilization. This study aimed to generate comprehensive plastome resources and develop molecular markers to support the phylogenetics, identification, and conservation management of C. amoena. Methods: Genome skimming was employed to assemble and annotate the complete plastomes of seven geographically distinct C. amoena accessions. Comparative analyses were conducted to assess structural features and sequence divergence within C. amoena and across related species in the Calypsoinae subtribe. Phylogenetic relationships were inferred from protein-coding genes. Simple sequence repeats (SSRs), dispersed repeats, and hypervariable regions were identified from the plastomes, while nuclear SSRs were developed from assembled nuclear sequences. Results: All seven plastomes exhibited a conserved quadripartite structure with identical gene content and order, showing only minor variations in genome size. Sequence divergence was mainly confined to non-coding regions. Across Calypsoinae species, mycoheterotrophic taxa exhibited reduced plastomes. Phylogenetic analyses resolved four well-supported intergeneric clades within Calypsoinae and revealed a notable divergence between the HuNGZ accession and other C. amoena accessions, which otherwise showed low plastome-level differentiation. We also identified 69–74 plastome-derived SSRs, 22–25 dispersed repeats, and three hypervariable regions that may serve as informative molecular markers for C. amoena. Additionally, 16 polymorphic nuclear SSRs were developed from assembled nuclear sequences. Conclusions: These findings significantly expand the genomic resources available for C. amoena and provide essential insights for its phylogeny, molecular identification, conservation management, and future breeding efforts. Full article

Bamboo orchid (Arundina graminifolia), a fast-growing evergreen terrestrial orchid with year-round flowering capacity, exhibits limited germplasm resources for white floral variants despite its ornamental significance. This study investigates the molecular basis of natural white flower formation through comparative analysis of purple- and white-flowered variants across bud, post-bud, and blooming stages. Histological examination revealed anthocyanin accumulation restricted to two to three upper epidermal cell layers in purple petals, while white petals showed complete pigment absence. Transcriptome profiling coupled with RT-qPCR validation identified eleven differentially expressed structural genes in anthocyanin biosynthesis. Notably, AgDFR expression remained undetectable across all white-flower developmental stages. Sequence analysis demonstrated identical 3030 bp promoter regions of AgDFR between two variants, while white-flower AgDFR coding sequences contained over 107 bp insertion after the 330th nucleotide, causing premature translation termination. Molecular marker validation confirmed the presence of a diagnostic 472 bp fragment in all colored variants (13 purple/pink lines) and its absence in white phenotypes. This study establishes that insertional mutagenesis in AgDFR’s coding region underlies natural white flower in A. graminifolia. The developed molecular marker enables reliable differentiation of white-flowered variants from pigmented counterparts, providing valuable tools for germplasm management and breeding programs. Full article

Developmental changes in the anatomy along with the maturation from ovaries to fruits and ovules to seeds were analyzed in two terrestrial species of the related genera Anacamptis and Serapias (Orchideae, Orchidaceae), using light and scanning electron microscopy. Our results show that the proliferation of the placentae and the differentiation of the ovules are well developed at the beginning of the anthesis. After fertilization of the ovules, a cavity of free air space is formed surrounding the embryo, contributing to the later buoyancy of seeds in both genera. At the last days of their development, the seeds showed slanting ridges in the periclinal walls of the testa cells. Raphides were observed in the valves, formed by packed needles composed of calcium oxalate, which contribute to avoiding herbivory. Lignification observed in the endocarp cells of the placenta and in the testa cells can be related to protecting the ovules and embryos. Terrestrial orchids need a faster maturation to ensure the efficacy of fertilization due to seasonal environmental changes in temperate areas, so developmental changes during the maturation of fruits and seeds take place in a shorter time than in epiphytic orchids. Full article

The leaf economic spectrum framework explains how plants optimize leaf traits for productivity, distribution, and stress tolerance. Orchids in Southwestern China’s karst forests, especially lithophytic species, are challenged by prolonged drought and limited light availability. This study investigated different leaf strategies between lithophytic and terrestrial orchids under the harsh karst environment. We measured key leaf traits, including photosynthesis, structure, biomechanics, nitrogen allocation, and water relations, in twenty-two lithophytic and six terrestrial orchids in a subtropical karst forest. After accounting for phylogenetic influences, we found that lithophytic orchids had a higher leaf mass per area, cuticle thickness, and biomechanical resistance (F_p) but a lower maximum photosynthetic rate (A_max-mass), nitrogen allocation to photosynthesis (N_T), and saturated water content (SWC) than terrestrial orchids. These results suggest that lithophytic orchids prioritize structural investment and stress tolerance over photosynthetic efficiency. Across species, N_T correlated positively with A_max-mass and negatively with F_p, highlighting nitrogen allocation as a key mechanism in leaf cost–benefit strategies. Additionally, SWC emerged as a critical driver of variation in multiple traits, supporting its integration into the leaf economic spectrum for orchids in karst ecosystems. This study offers new insights into orchid adaptation in subtropical karst environments, with implications for plant resilience under changing climates. Full article

Forest Orchidaceae are important for European temperate forests, yet their distribution and abundance have so far interested limited research. In three pure or mixed silver fir stands in the Foreste Casentinesi National Park (NP) (Northern Apennines, Italy) we analysed how structural traits in mature and old-growth forests affected orchid communities in terms of abundance of the main genera, trophic strategy and rarity in the NP. We established three 20 × 60 m plots to quantify the structure of living and dead tree community, including a set of old-growth attributes connected to large trees, deadwood, and established regeneration. In each plot, we measured the abundance of all orchid species and explored their behaviour according to the trophic strategy (autotrophy/mixotrophy, obligate mycoheterotrophy), rarity within the NP, and threatened status according to the IUCN Red List. We used multivariate ordination and classification techniques to assess plot similarities according to forest structure and Orchid Community and identify the main structural factors related to orchid features. The main structural factors were used as predictors of community traits. Forest composition (i.e., the dominance/abundance of silver fir) affected the presence of the main orchid genera: Epipactis were abundant in silver fir-dominated forests, Cephalanthera in mixed beech and fir forests. Interestingly, Cephalanthera could become limited even in beech-dominated conditions if fir regeneration was abundant and established. Old-growth attributes like the density of deadwood and large tree volume were important determinants of the presence of rare and mycoheterotrophic species. Our results provided a first quantitative description of forest reference conditions to be used in the protection and restoration of threatened and rare orchid species. Full article

The genus Cymbidium, with its intricate floral elements, pronounced endemicity, and patchy distribution, evolves a rich diversity of morphological forms and a wide variety of species while causing an indistinctness in the classification of its species. To elucidate the phylogenetic relationships among Cymbidium species and enhance their taxonomic classification by DNA barcoding, this study conducted amplification and sequence results of nuclear (ITS) and chloroplast genes (matK, rbcL, trnL-F, psbA-trnH) with phenotypic genetic diversity analysis, genetic distance analysis, and phylogenetic analysis from 48 samples of Cymbidium species. The comparison of genetic distance variations showed that psbA-trnH, ITS + psbA-trnH, and ITS + matK + psbA-trnH exhibit minimal overlap and significant genetic variation within Cymbidium species. The phylogenetic analysis indicated that the combination, ITS + matK + psbA-trnH, has the highest identification rate. Notably, both the phylogenetic analysis and the genetic diversity analysis of phenotypic traits consistently indicated a clear divergence between epiphytic and terrestrial orchids, with epiphytic orchids forming a distinct clade. This provides reference evidence for studying the ecological adaptations and evolutionary differences between epiphytic and terrestrial orchids, as well as a scientific basis for the classification and identification, germplasm conservation, resource utilization, and phylogenetic evolution of orchids. Full article

Orchids have evolved flowers with unique morphologies through coevolution with pollinators, such as insects. Among the floral organs, the lip (labellum), one of the three petals, exhibits a distinctive shape and plays a crucial role in attracting pollinators and facilitating pollination in many orchids. The lip of the terrestrial orchid Habenaria radiata is shaped like a flying white bird and is believed to attract and provide a platform for nectar-feeding pollinators, such as hawk moths. To elucidate the mechanism of lip morphogenesis, we conducted time-lapse imaging of blooming flowers to observe the extension process of the lip and analyzed the cellular morphology during the generation of serrations. We found that the wing part of the lip folds inward in the bud and fully expands in two hours after blooming. The serrations of the lip were initially formed through cell division and later deepened through polar cell elongation. Transcriptome analysis of floral buds revealed the expression of genes involved in floral organ development, cell division, and meiosis. Additionally, genes involved in serration formation are also expressed in floral buds. This study provides insights into the mechanism underlying the formation of the unique lip morphology in Habenaria radiata. Full article

Cryptostylis ovata is a terrestrial orchid endemic to southwestern Australia. The virus status of C. ovata has not been studied. Eighty-three C. ovata samples from 16 populations were collected, and sequencing was used to identify RNA viruses from them. In one population, all tested plants were co-infected with isolates of the exotic-to-Australia viruses Ornithogalum mosaic virus (OrMV) and bean yellow mosaic virus (BYMV). In another population, one plant was infected with BYMV. No viruses were detected in the remaining populations. The OrMV isolate shared 98–99% nucleotide identity with isolates identified from wild indigenous Lachenalia (Iridaceae) plants in South Africa. This suggests that the source of OrMV in C. ovata may be one or more bulbous iridaceous flowering plants of southern African origin that were introduced to Western Australia as ornamentals and that have since become invasive weeds. One BYMV isolate from C. ovata also exhibited 99% nucleotide identity with strains isolated from the exotic leguminous crop Lupinus angustifolius in Western Australia, suggesting possible spillover to indigenous species from this source. This study with C. ovata highlights the probable role of invasive weeds and exotic crops as sources of exotic virus spillovers to indigenous plants. Full article

Terrestrial orchid tubers are an important source of food in some parts of Africa and are traditionally included in the diets of most rural communities in Malawi. However, there is limited information on the nutritional and phytochemical content of the Malawian orchids to substantiate their traditional use. The present study evaluates the nutritional and phytochemical variation of four orchid species: Disa zombica, Satyrium buchananii, Satyrium carsonii, and Satyrium trinerve, collected from the same ecological zone of Malawi. The proximate content, minerals, phytochemicals, and functional properties were analysed using official procedures. Protein ranged from 2.19% to 4.65%, whereas carbohydrate ranged from 65.24% to 80.22%, with S. carsonii and S. trinerve registering the highest protein and carbohydrate contents, respectively. Iron and potassium were highest in D. zombica, while sodium and calcium were highest in S. buchananii. The total phenolics ranged from 228.56 to 500.00 mg GAE/100 g, with D. zombica registering the highest. The water absorption capacity ranged from 4.10 to 10.88 g/g. Despite variable levels, the study provides evidence that orchid species contain essential nutrients and phytochemicals important for human nutrition and health. Furthermore, the functional properties can be utilised in the development of food products, such as baked products. Full article

Habenaria and Liparis are well-known orchid genera that grow in terrestrial habitats in the tropics, subtropics or temperate zones. Three species have been found in subtropical regions of China, inhabiting terrestrial to epiphytic habitats. This study focuses on three species, H. dentata (distributed in Asia), H. yachangensis, and L. gigantea. For H. yachangensis and L. gigantea, there is no information about the mycorrhizal community in these species. This study aims to conduct the fungal community screening of Chinese ground orchids from subtropical regions. We performed a comparative analysis of the fungal community among H. dentata, H. yachangensis, and L. gigantea, determining their ITS regions using NGS paired-end sequences. The results clarified the diversity and the predominance of fungal genera. Ascomycota was abundant compared to Basidiomycota or other fungi groups in all communities, with a high dominance in all populations, especially for L. gigantea. At different root spatial locations, the fungal community diversity and richness were higher in the soil than in the rhizosphere or inner root. However, the results suggest that L. gigantea has a different fungal community compared to Habenaria species. In this order, the subtropical terrestrial orchids have a different fungal network compared to the northern terrestrial orchids. Also, there is a high probability of co-existence and co-evolution of endophytic fungi in these terrestrial orchids, indicating the potential role of host plants in selecting an endophytic fungal community. Furthermore, our results highlight the need to elucidate the microbe interactions of these unique orchids for long-term purposes, such as isolating indigenous fungi for suitable inoculants for further orchid propagation, restoration, and conservation. Full article

Conservation Translocation (CT), which includes reintroduction, reinforcement and introduction, is gaining momentum, responding to serious population decline in many orchids. Orchid conservation underpinned by a greater emphasis on understanding biotic and abiotic factors of habitats is critical for successful recovery and restoration programmes. Anacamptis morio, commonly known as green-winged orchid (GWO), is a terrestrial orchid found throughout Europe, but populations in England rapidly declined in its native range in the last several decades. The current study explored the relationship between soil abiotic characteristics and the community composition of key fungal groups. Wild sites in Essex and Cumbria in England, where successful colonies are currently present, were compared to potential sites for CT in Cumbria. The Cumbrian sites managed by cattle grazing include the wild site and three potential CT sites, with two of them hosting no GWO plants. The Essex site, fOxley Meadow, where no cattle is used for grassland management, hosts the largest population of GWO in England. The aim of this study was to understand whether the community composition of fungi and soil characteristics of the potential CT sites in Cumbria are nearly compatible with that of Oxley Meadow. Oxley Meadow, with around 65,000 plants, stands out as a unique habitat compared to all Cumbria sites, as it showed low organic content. Nitrate and phosphate content were smaller for Oxley Meadow compared to other Cumbrian sites. The proportion of Basidiomycota fungi was greater in Oxley Meadow compared to all Cumbrian sites where Ascomycota dominated. The abundant fungal group found in Oxley Meadow was Agaricales. From Agariclaes, Hygrophoraceae or waxcaps fungi are considered an indicator group of fungi and were the most abundant group in Oxley Meadow. They have a negative correlation with targeted key fungal groups and abiotic parameters. More in-depth assessments using additional primers are essential to better understand the fungal diversity and how this diversity translates to the resilience of orchid habitats. This preliminary study points to future studies to assess whether sites are near-compatible to the wild site where large colonies are present using additional primers collected over different time scales. Full article

Clearcutting has tended to simplify forest structure and species composition, with potential negative consequences for biodiversity. Retention forestry emerged as an alternative to minimize this concern in intensively managed forests. In central Mexico, this approach was first implemented a decade ago in temperate forests, but an examination of its effects on floristic diversity and composition is non-existent. We evaluated and compared richness, diversity, and floristic composition among harvested, retention, and conserved areas in a conifer-dominated forest of central Mexico, with various parametric and non-parametric analyses. Species’ ecological and structural importance was also evaluated. We recorded 138 species, 95 genera, and 44 families of plants. Harvested areas listed the most species (99) with herb dominance, tree homogeneity, and the highest number of exotics. Retention and conserved areas’ floristic composition was similar, with the presence of epiphytes and terrestrial orchids, considered indicators of conservation. The retention areas recorded rare and endangered species, tree heterogeneity, and juveniles of structural species of temperate forests. Conserved areas showed a greater number of structural mature elements and exclusive species, though there was a smaller species number (75). We demonstrated that retention forestry is achieving its goal by maintaining the structural elements, habitats, and plant diversity of the temperate forests analyzed. Full article

Cymbidium sinense, a type of orchid plant, is more drought-resistant and ornamental than other terrestrial orchids. Research has shown that many members of the NUCLEAR FACTOR Y (NF-Y) transcription factor family are responsive to plant growth, development, and abiotic stress. However, the mechanism of the NF-Y gene family’s response to abiotic stress in orchids has not yet been reported. In this study, phylogenetic analysis allowed for 27 CsNF-Y genes to be identified (5 CsNF-YAs, 9 CsNF-YBs, and 13 CsNF-YC subunits), and the CsNF-Ys were homologous to those in Arabidopsis and Oryza. Protein structure analysis revealed that different subfamilies contained different motifs, but all of them contained Motif 2. Secondary and tertiary protein structure analysis indicated that the CsNF-YB and CsNF-YC subfamilies had a high content of alpha helix structures. Cis-element analysis showed that elements related to drought stress were mainly concentrated in the CsNF-YB and CsNF-YC subfamilies, with CsNF-YB3 and CsNF-YC12 having the highest content. The results of a transcriptome analysis showed that there was a trend of downregulation of almost all CsNF-Ys in leaves under drought stress, while in roots, most members of the CsNF-YB subfamily showed a trend of upregulation. Additionally, seven genes were selected for real-time reverse transcription quantitative PCR (qRT-PCR) experiments. The results were generally consistent with those of the transcriptome analysis. The regulatory roles of CsNF-YB 1, 2, and 4 were particularly evident in the roots. The findings of our study may make a great contribution to the understanding of the role of CsNF-Ys in stress-related metabolic processes. Full article