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Fu S, Yang Y, Wang P, Ying Z, Xu W, Zhou Z. Comparative transcriptomic analysis of normal and abnormal in vitro flowers in Cymbidium nanulum Y. S. Wu et S. C. Chen identifies differentially expressed genes and candidate genes involved in flower formation. FRONTIERS IN PLANT SCIENCE 2022; 13:1007913. [PMID: 36352857 PMCID: PMC9638074 DOI: 10.3389/fpls.2022.1007913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 10/04/2022] [Indexed: 06/16/2023]
Abstract
It is beneficial for breeding and boosting the flower value of ornamental plants such as orchids, which can take several years of growth before blooming. Over the past few years, in vitro flowering of Cymbidium nanulum Y. S. Wu et S. C. Chen has been successfully induced; nevertheless, the production of many abnormal flowers has considerably limited the efficiency of this technique. We carried out transcriptomic analysis between normal and abnormal in vitro flowers, each with four organs, to investigate key genes and differentially expressed genes (DEGs) and to gain a comprehensive perspective on the formation of abnormal flowers. Thirty-six DEGs significantly enriched in plant hormone signal transduction, and photosynthesis-antenna proteins pathways were identified as key genes. Their broad upregulation and several altered transcription factors (TFs), including 11 MADS-box genes, may contribute to the deformity of in vitro flowers. By the use of weighted geneco-expression network analysis (WGCNA), three hub genes, including one unknown gene, mitochondrial calcium uniporter (MCU) and harpin-induced gene 1/nonrace-specific disease resistance gene 1 (NDR1/HIN1-Like) were identified that might play important roles in floral organ formation. The data presented in our study may serve as a comprehensive resource for understanding the regulatory mechanisms underlying flower and floral organ formation of C. nanulum Y. S. Wu et S. C. Chen in vitro.
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Kaur S. In Vitro Florigenesis with Special Reference to Orchids- A Review. Recent Pat Biotechnol 2022; 16:311-318. [PMID: 35430983 DOI: 10.2174/1872208316666220415124439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 11/10/2021] [Accepted: 12/16/2021] [Indexed: 06/14/2023]
Abstract
BACKGROUND Orchids are widely used in floriculture as attractive cut flowers all over the world. The current paper reviews factors affecting the in vitro flowering in orchid species. METHODS The phenomenon of in vitro flowering is advantageous as it shortens the breeding cycle, which is prolonged in the in vivo grown orchid species of commercial value. Certain genetic and biochemical mechanisms are involved at the time of onset of flowering in orchid plants. In the present endeavour, efforts have been made to initiate in vitro flowering in terrestrial and epiphytic orchid species. Various phenomenon involved during transition of vegetative shoot apex into floral axis is also reviewed. RESULTS In vitro flowering was induced in Dendrobium nobile and Zeuxine strateumatica in Mitra medium supplemented with BAP at 0.5 in mgl-1. CONCLUSION In vitro flowering can be initiated by manipulating physical and chemical stimulus in the nutrient regime. The study would be helpful in better understanding the complex process of flowering in vitro as well as ex vitro.
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Affiliation(s)
- Saranjeet Kaur
- Department of Biosciences, University Institute of Biotechnology, Chandigarh University, Distt.- Mohali, Punjab, India
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A 20 y Analysis of Weather and Management Effects on a Small White Lady's-slipper (Cypripedium candidum) Population in Manitoba. AMERICAN MIDLAND NATURALIST 2021. [DOI: 10.1674/0003-0031-185.1.32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Gholami S, Vafaee Y, Nazari F, Ghorbani A. Molecular characterization of endangered Iranian terrestrial orchids using ISSR markers and association with floral and tuber-related phenotypic traits. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2021; 27:53-68. [PMID: 33627962 PMCID: PMC7873147 DOI: 10.1007/s12298-020-00920-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 11/20/2020] [Accepted: 12/28/2020] [Indexed: 05/13/2023]
Abstract
We aimed to study the genetic diversity, population structure, and phylogeny of Iranian orchids using inter-simple sequence repeat (ISSR) markers to find markers associated with phenotypic traits. Based on the phenotypic analysis, the inflorescence length and the flower number of studied accessions ranged from 3.92 to 27.13 cm and 5 to 50, respectively. On the other hand, the tuber length ranged from 1.80 to 9.35 cm. A total of 310 reproducible ISSR fragments with a size range of 150 to 3000 bp were amplified. ISSR primers provided an average polymorphism information content of 0.391, varied from 0.488 for UBC-876 to 0.351 for UBC-842. Os.J population showed the lowest genetic diversity (H = 0.057 and I = 0.075), while Oyst.JA population showed the highest genetic diversity (H = 0.114 and I = 0.158). At species level, the average coefficient of genetic differentiation (G ST) ranged from 0.265 for Orchis simia to 0.587 for Himantoglossum affine. Gene flow (Nm) varied from 1.38 (O. simia) to 0.756 (Anacamptis collina). The UPGMA genetic similarity dendrogram using Jaccard coefficients (r = 0.973) revealed six main clusters. Based on the Bayesian clustering method, the highest probability of the data was achieved when accessions were divided into eight groups. Floral and tuber-related phenotypic traits represented high correlations together, and they were associated with some ISSR bands based on the multiple association analysis. Altogether, ISSR markers proved to be useful for discrimination and clarification of the relationships among species and populations collected from geographically different locations. Furthermore, it could identify the polymorphism among accessions within each population and species. SUPPLEMENTARY INFORMATION The online version of this article (10.1007/s12298-020-00920-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Soheila Gholami
- Department of Horticultural Science and Engineering, Faculty of Agriculture, University of Kurdistan, 66177-15175 Sanandaj, Iran
| | - Yavar Vafaee
- Department of Horticultural Science and Engineering, Faculty of Agriculture, University of Kurdistan, 66177-15175 Sanandaj, Iran
- Medicinal Plants Breeding and Development Research Institute, University of Kurdistan, 66177-15175 Sanandaj, Iran
| | - Farzad Nazari
- Department of Horticultural Science and Engineering, Faculty of Agriculture, University of Kurdistan, 66177-15175 Sanandaj, Iran
| | - Abdolbaset Ghorbani
- Department of Organismal Biology, Evolutionary Biology Centre, Uppsala University, Norbyvagen 18D, 75236 Uppsala, Sweden
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Ovule Development and in Planta Transformation of Paphiopedilum Maudiae by Agrobacterium-Mediated Ovary-Injection. Int J Mol Sci 2020; 22:ijms22010084. [PMID: 33374823 PMCID: PMC7795287 DOI: 10.3390/ijms22010084] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Revised: 12/20/2020] [Accepted: 12/21/2020] [Indexed: 11/23/2022] Open
Abstract
In this paper, the development of the Paphiopedilum Maudiae embryo sac at different developmental stages after pollination was assessed by confocal laser scanning microscopy. The mature seeds of P. Maudiae consisted of an exopleura and a spherical embryo, but without an endosperm, while the inner integument cells were absorbed by the developing embryo. The P. Maudiae embryo sac exhibited an Allium type of development. The time taken for the embryo to develop to a mature sac was 45-50 days after pollination (DAP) and most mature embryo sacs had completed fertilization and formed zygotes by about 50–54 DAP. In planta transformation was achieved by injection of the ovaries by Agrobacterium, resulting in 38 protocorms or seedlings after several rounds of hygromycin selection, corresponding to 2, 7, 5, 1, 3, 4, 9, and 7 plantlets from Agrobacterium-mediated ovary-injection at 30, 35, 42, 43, 45, 48, 50, and 53 DAP, respectively. Transformation efficiency was highest at 50 DAP (2.54%), followed by 2.48% at 53 DAP and 2.45% at 48 DAP. Four randomly selected hygromycin-resistant plants were GUS-positive after PCR analysis. Semi-quantitative PCR and quantitative real-time PCR analysis revealed the expression of the hpt gene in the leaves of eight hygromycin-resistant seedlings following Agrobacterium-mediated ovary-injection at 30, 35, 42, 43, 45, 48, 50, and 53 DAP, while hpt expression was not detected in the control. The best time to inject P. Maudiae ovaries in planta with Agrobacterium is 48-53 DAP, which corresponds to the period of fertilization. This protocol represents the first genetic transformation protocol for any Paphiopedilum species and will allow for expanded molecular breeding programs to introduce useful and interesting genes that can expand its ornamental and horticulturally important characteristics.
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Gao JG, Liu H, Wang N, Yang J, Zhang XL. Plant extinction excels plant speciation in the Anthropocene. BMC PLANT BIOLOGY 2020; 20:430. [PMID: 32938403 PMCID: PMC7493330 DOI: 10.1186/s12870-020-02646-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 09/10/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND In the past several millenniums, we have domesticated several crop species that are crucial for human civilization, which is a symbol of significant human influence on plant evolution. A pressing question to address is if plant diversity will increase or decrease in this warming world since contradictory pieces of evidence exit of accelerating plant speciation and plant extinction in the Anthropocene. RESULTS Comparison may be made of the Anthropocene with the past geological times characterised by a warming climate, e.g., the Palaeocene-Eocene Thermal Maximum (PETM) 55.8 million years ago (Mya)-a period of "crocodiles in the Arctic", during which plants saw accelerated speciation through autopolyploid speciation. Three accelerators of plant speciation were reasonably identified in the Anthropocene, including cities, polar regions and botanical gardens where new plant species might be accelerating formed through autopolyploid speciation and hybridization. CONCLUSIONS However, this kind of positive effect of climate warming on new plant species formation would be thoroughly offset by direct and indirect intensive human exploitation and human disturbances that cause habitat loss, deforestation, land use change, climate change, and pollution, thus leading to higher extinction risk than speciation in the Anthropocene. At last, four research directions are proposed to deepen our understanding of how plant traits affect speciation and extinction, why we need to make good use of polar regions to study the mechanisms of dispersion and invasion, how to maximize the conservation of plant genetics, species, and diverse landscapes and ecosystems and a holistic perspective on plant speciation and extinction is needed to integrate spatiotemporally.
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Affiliation(s)
- Jian-Guo Gao
- Department of Ecology, College of Urban and Environmental Sciences, and Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, No.5 Yiheyuan Road Haidian District, Beijing, 100871, China.
| | - Hui Liu
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, Chinese Academy of Sciences, 723 Xingke Road, Guangzhou, 510650, China
| | - Ning Wang
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Jing Yang
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, Department of Biostatistics and Computational Biology, School of Life Sciences, Fudan University, Shanghai, China
| | - Xiao-Ling Zhang
- Department of Public Policy, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
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Revathi J, Manokari M, Latha R, Priyadharshini S, Kher MM, Shekhawat MS. In vitro propagation, in vitro flowering, ex vitro root regeneration and foliar micro-morphological analysis of Hedyotis biflora (Linn.) Lam. ACTA ACUST UNITED AC 2019. [DOI: 10.1007/s42535-019-00066-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Hoang NH, Kane ME, Radcliffe EN, Zettler LW, Richardson LW. Comparative seed germination and seedling development of the ghost orchid, Dendrophylax lindenii (Orchidaceae), and molecular identification of its mycorrhizal fungus from South Florida. ANNALS OF BOTANY 2017; 119:379-393. [PMID: 28025292 PMCID: PMC5314644 DOI: 10.1093/aob/mcw220] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 08/01/2016] [Accepted: 08/11/2016] [Indexed: 05/11/2023]
Abstract
BACKGROUND AND AIMS The endangered leafless ghost orchid, Dendrophylax lindenii, one of the most renowned orchids in the world, is difficult to grow under artificial conditions. Published information on asymbiotic and symbiotic (co-culture with a mycobiont) seed germination, seedling anatomy and developmental morphology of this leafless orchid is completely lacking. This information is critical for the development of efficient procedures for ghost orchid production for successful reintroduction. METHODS Ghost orchid seedling early development stages were morphologically and anatomically defined to compare germination, embryo and protocorm maturation and seedling development during asymbiotic and symbiotic culture with one of two mycorrhizal strains (Dlin-379 and Dlin-394) isolated from ghost orchid roots in situ KEY RESULTS: Seeds symbiotically germinated at higher rates when cultured with fungal strain Dlin-394 than with strain Dlin-379 or asymbiotically on P723 medium during a 10-week culture period. Fungal pelotons were observed in protocorm cells co-cultured with strain Dlin-394 but not Dlin-379. Some 2-year-old seedlings produced multinode inflorescences in vitro Production of keikis from inflorescence nodes indicated the capacity for clonal production in the ghost orchid. CONCLUSIONS Ghost orchid embryo and seedling development were characterized into seven stages. Fungal strain Dlin-394 was confirmed as a possible ghost orchid germination mycobiont, which significantly promoted seed germination and seedling development. Internal transcribed spacer sequencing data confirmed that Dlin-394 belongs within the genus Ceratobasidium These results offer the opportunity to examine the benefits of using a mycobiont to enhance in vitro germination and possibly ex vitro acclimatization and sustainability following outplanting.
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Affiliation(s)
- Nguyen H Hoang
- Environmental Horticulture Department, University of Florida, PO Box 110675, Gainesville, FL 32611, USA
- Department of Plant Biotechnology, University of Sciences, 227 Nguyen Van Cu, Ho Chi Minh City, Vietnam
| | - Michael E Kane
- Environmental Horticulture Department, University of Florida, PO Box 110675, Gainesville, FL 32611, USA
| | - Ellen N Radcliffe
- Orchid Recovery Program, Biology Department, Illinois College, 1101 West College Avenue, Jacksonville, IL 62650, USA and
| | - Lawrence W Zettler
- Orchid Recovery Program, Biology Department, Illinois College, 1101 West College Avenue, Jacksonville, IL 62650, USA and
| | - Larry W Richardson
- Florida Panther National Wildlife Refuge, U.S. Fish and Wildlife Service, 12085 SR 29 South Immokalee, FL 34142, USA
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Teixeira da Silva JA, Kher MM, Soner D, Page T, Zhang X, Nataraj M, Ma G. Sandalwood: basic biology, tissue culture, and genetic transformation. PLANTA 2016; 243:847-87. [PMID: 26745967 DOI: 10.1007/s00425-015-2452-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 12/16/2015] [Indexed: 05/07/2023]
Abstract
Sustainable resource preservation of Santalum species that yield commercially important forest products is needed. This review provides an understanding of their basic biology, propagation, hemi-parasitic nature, reproductive biology, and biotechnology. Many species of the genus Santalum (Santalaceae) have been exploited unremittingly for centuries, resulting in the extinction of one and the threatened status of three other species. This reduction in biodiversity of sandalwood has resulted from the commercial exploitation of its oil-rich fragrant heartwood. In a bid to conserve the remaining germplasm, biotechnology provides a feasible, and effective, means of propagating members of this genus. This review provides a detailed understanding of the biological mechanisms underlying the success or failure of traditional propagation, including a synopsis of the process of hemi-parasitism in S. album, and of the suitability of host plants to sustain the growth of seedlings and plants under forestry production. For the mass production of economically important metabolites, and to improve uniformity of essential oils, the use of clonal material of similar genetic background for cultivation is important. This review summarizes traditional methods of sandalwood production with complementary and more advanced in vitro technologies to provide a basis for researchers, conservationists and industry to implement sustainable programs of research and development for this revered genus.
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Affiliation(s)
| | - Mafatlal M Kher
- B.R. Doshi School of Biosciences, Sardar Patel University, Sardar Patel Maidan, Vadtal Rd., P.O. Box 39, Vallabh Vidyanagar, Gujarat, 388120, India.
| | - Deepak Soner
- B.R. Doshi School of Biosciences, Sardar Patel University, Sardar Patel Maidan, Vadtal Rd., P.O. Box 39, Vallabh Vidyanagar, Gujarat, 388120, India.
| | - Tony Page
- Forests and People Research Centre, University of Sunshine Coast, Maroochydore DC, Locked Bag 4, Sunshine Coast, QLD, 4558, Australia.
| | - Xinhua Zhang
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, the Chinese Academy of Sciences, Guangzhou, 510650, China.
| | - M Nataraj
- B.R. Doshi School of Biosciences, Sardar Patel University, Sardar Patel Maidan, Vadtal Rd., P.O. Box 39, Vallabh Vidyanagar, Gujarat, 388120, India.
| | - Guohua Ma
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, the Chinese Academy of Sciences, Guangzhou, 510650, China.
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da Silva JAT, Dobránszki J, Cardoso JC, Chandler SF, Zeng S. Methods for genetic transformation in Dendrobium. PLANT CELL REPORTS 2016; 35:483-504. [PMID: 26724929 DOI: 10.1007/s00299-015-1917-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 11/28/2015] [Accepted: 12/01/2015] [Indexed: 05/07/2023]
Abstract
The genetic transformation of Dendrobium orchids will allow for the introduction of novel colours, altered architecture and valuable traits such as abiotic and biotic stress tolerance. The orchid genus Dendrobium contains species that have both ornamental value and medicinal importance. There is thus interest in producing cultivars that have increased resistance to pests, novel horticultural characteristics such as novel flower colours, improved productivity, longer flower spikes, or longer post-harvest shelf-life. Tissue culture is used to establish clonal plants while in vitro flowering allows for the production of flowers or floral parts within a sterile environment, expanding the selection of explants that can be used for tissue culture or genetic transformation. The latter is potentially the most effective, rapid and practical way to introduce new agronomic traits into Dendrobium. Most (69.4 %) Dendrobium genetic transformation studies have used particle bombardment (biolistics) while 64 % have employed some form of Agrobacterium-mediated transformation. A singe study has explored ovary injection, but no studies exist on floral dip transformation. While most of these studies have involved the use of selector or reporter genes, there are now a handful of studies that have introduced genes for horticulturally important traits.
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Affiliation(s)
- Jaime A Teixeira da Silva
- , P. O. Box 7, Miki-cho Post Office, Ikenobe 3011-2, Miki-cho, Kita-gun, Kagawa-ken, 761-0799, Japan.
| | - Judit Dobránszki
- Research Institute of Nyíregyháza, University of Debrecen, P.O. Box 12, Nyíregyháza, 4400, Hungary.
| | - Jean Carlos Cardoso
- Department of Rural Development, Centro de Ciências Agrárias, UFSCar, Via Anhanguera, Km 174, CP 153, Araras City, CEP 13.600-970, Brazil.
| | - Stephen F Chandler
- School of Applied Sciences, RMIT University, Bundoora, VIC, 3083, Australia.
| | - Songjun Zeng
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Gene Improvement, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China.
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Teixeira da Silva JA, Tsavkelova EA, Zeng S, Ng TB, Parthibhan S, Dobránszki J, Cardoso JC, Rao MV. Symbiotic in vitro seed propagation of Dendrobium: fungal and bacterial partners and their influence on plant growth and development. PLANTA 2015; 242:1-22. [PMID: 25940846 DOI: 10.1007/s00425-015-2301-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 04/08/2015] [Indexed: 05/27/2023]
Abstract
The genus Dendrobium is one of the largest genera of the Orchidaceae Juss. family, although some of its members are the most threatened today. The reason why many species face a vulnerable or endangered status is primarily because of anthropogenic interference in natural habitats and commercial overexploitation. The development and application of modern techniques and strategies directed towards in vitro propagation of orchids not only increases their number but also provides a viable means to conserve plants in an artificial environment, both in vitro and ex vitro, thus providing material for reintroduction. Dendrobium seed germination and propagation are challenging processes in vivo and in vitro, especially when the extreme specialization of these plants is considered: (1) their biotic relationships with pollinators and mycorrhizae; (2) adaptation to epiphytic or lithophytic life-styles; (3) fine-scale requirements for an optimal combination of nutrients, light, temperature, and pH. This review also aims to summarize the available data on symbiotic in vitro Dendrobium seed germination. The influence of abiotic factors as well as composition and amounts of different exogenous nutrient substances is examined. With a view to better understanding how to optimize and control in vitro symbiotic associations, a part of the review describes the strong biotic relations of Dendrobium with different associative microorganisms that form microbial communities with adult plants, and also influence symbiotic seed germination. The beneficial role of plant growth-promoting bacteria is also discussed.
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Ogura-Tsujita Y, Miyoshi K, Tsutsumi C, Yukawa T. First flowering hybrid between autotrophic and mycoheterotrophic plant species: breakthrough in molecular biology of mycoheterotrophy. JOURNAL OF PLANT RESEARCH 2014; 127:299-305. [PMID: 24310615 DOI: 10.1007/s10265-013-0612-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Accepted: 10/28/2013] [Indexed: 06/02/2023]
Abstract
Among land plants, which generally exhibit autotrophy through photosynthesis, about 880 species are mycoheterotrophs, dependent on mycorrhizal fungi for their carbon supply. Shifts in nutritional mode from autotrophy to mycoheterotrophy are usually accompanied by evolution of various combinations of characters related to structure and physiology, e.g., loss of foliage leaves and roots, reduction in seed size, degradation of plastid genome, and changes in mycorrhizal association and pollination strategy. However, the patterns and processes involved in such alterations are generally unknown. Hybrids between autotrophic and mycoheterotrophic plants may provide a breakthrough in molecular studies on the evolution of mycoheterotrophy. We have produced the first hybrid between autotrophic and mycoheterotrophic plant species using the orchid group Cymbidium. The autotrophic Cymbidium ensifolium subsp. haematodes and mycoheterotrophic C. macrorhizon were artificially pollinated, and aseptic germination of the hybrid seeds obtained was promoted by sonication. In vitro flowering was observed five years after seed sowing. Development of foliage leaves, an important character for photosynthesis, segregated in the first generation; that is, some individuals only developed scale leaves on the rhizome and flowering stems. However, all of the flowering plants formed roots, which is identical to the maternal parent.
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Affiliation(s)
- Yuki Ogura-Tsujita
- Botanical Gardens Tohoku University, Kawauchi 12-1, Aobaku, Sendai, 980-0862, Japan,
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