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Carrion JV, Perez J, Tineo D, Calderon MS, Garcia L, Oliva M, Gamarra Torres O, Bustamante DE. High-throughput sequencing yields the complete plastid genome of the endemic species Phragmipedium kovachii (Orchidaceae) from northeastern Peru. Mitochondrial DNA B Resour 2024; 9:1175-1180. [PMID: 39247500 PMCID: PMC11378673 DOI: 10.1080/23802359.2024.2397979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Accepted: 08/24/2024] [Indexed: 09/10/2024] Open
Abstract
Phragmipedium kovachii is a species of orchid endemic to the Amazonas and San Martín regions. Unfortunately, its excessive extraction has made it a critically endangered species. In this study, we performed next-generation sequencing of P. kovachii (GenBank accession number OR348669) and assembled its complete chloroplast genome. The complete chloroplast genome of P. kovachii is A + T-rich (64.3%), measuring 152,918 bp in length. This plastid genome contains a total of 124 genes (77 protein-coding genes, 39 tRNAs, and eight rRNAs) and five pseudogenes, including a pair of inverted repeats (IRs) 25,116 bp in size and separated by a large single-copy (LSC) region of 89,216 bp and a small single-copy (SSC) region of 13,470 bp. This genome has a typical quadripartite organization following the structure of other Orchidaceae plastomes. Phylogenetic analyses revealed the close relationship between P. kovachii and P. besseae. This study contributes to the understanding of the phylogenetic relationships of the monophyletic group Cypripedioideae.
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Affiliation(s)
- Jois V Carrion
- Instituto de Investigación para el Desarrollo Sustentable de Ceja de Selva (INDES-CES), Universidad Nacional Toribio Rodríguez de Mendoza, Chachapoyas, Peru
| | - Jhordy Perez
- Instituto de Investigación para el Desarrollo Sustentable de Ceja de Selva (INDES-CES), Universidad Nacional Toribio Rodríguez de Mendoza, Chachapoyas, Peru
| | - Daniel Tineo
- Instituto de Investigación para el Desarrollo Sustentable de Ceja de Selva (INDES-CES), Universidad Nacional Toribio Rodríguez de Mendoza, Chachapoyas, Peru
| | - Martha S Calderon
- Instituto de Investigación para el Desarrollo Sustentable de Ceja de Selva (INDES-CES), Universidad Nacional Toribio Rodríguez de Mendoza, Chachapoyas, Peru
- Instituto de Investigación en Ingeniería Ambiental (INAM), Facultad de Ingeniería Civil y Ambiental (FICIAM), Universidad Nacional Toribio Rodríguez de Mendoza, Chachapoyas, Peru
| | - Ligia Garcia
- Instituto de Investigación para el Desarrollo Sustentable de Ceja de Selva (INDES-CES), Universidad Nacional Toribio Rodríguez de Mendoza, Chachapoyas, Peru
| | - Manuel Oliva
- Instituto de Investigación para el Desarrollo Sustentable de Ceja de Selva (INDES-CES), Universidad Nacional Toribio Rodríguez de Mendoza, Chachapoyas, Peru
| | - Oscar Gamarra Torres
- Instituto de Investigación en Ingeniería Ambiental (INAM), Facultad de Ingeniería Civil y Ambiental (FICIAM), Universidad Nacional Toribio Rodríguez de Mendoza, Chachapoyas, Peru
| | - Danilo E Bustamante
- Instituto de Investigación para el Desarrollo Sustentable de Ceja de Selva (INDES-CES), Universidad Nacional Toribio Rodríguez de Mendoza, Chachapoyas, Peru
- Instituto de Investigación en Ingeniería Ambiental (INAM), Facultad de Ingeniería Civil y Ambiental (FICIAM), Universidad Nacional Toribio Rodríguez de Mendoza, Chachapoyas, Peru
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Madrigal Y, Alzate JF, Pabón-Mora N. Evolution of major flowering pathway integrators in Orchidaceae. PLANT REPRODUCTION 2024; 37:85-109. [PMID: 37823912 PMCID: PMC11180029 DOI: 10.1007/s00497-023-00482-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 09/10/2023] [Indexed: 10/13/2023]
Abstract
The Orchidaceae is a mega-diverse plant family with ca. 29,000 species with a large variety of life forms that can colonize transitory habitats. Despite this diversity, little is known about their flowering integrators in response to specific environmental factors. During the reproductive transition in flowering plants a vegetative apical meristem (SAM) transforms into an inflorescence meristem (IM) that forms bracts and flowers. In model grasses, like rice, a flowering genetic regulatory network (FGRN) controlling reproductive transitions has been identified, but little is known in the Orchidaceae. In order to analyze the players of the FRGN in orchids, we performed comprehensive phylogenetic analyses of CONSTANS-like/CONSTANS-like 4 (COL/COL4), FLOWERING LOCUS D (FD), FLOWERING LOCUS C/FRUITFULL (FLC/FUL) and SUPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) gene lineages. In addition to PEBP and AGL24/SVP genes previously analyzed, here we identify an increase of orchid homologs belonging to COL4, and FUL gene lineages in comparison with other monocots, including grasses, due to orchid-specific gene lineage duplications. Contrariwise, local duplications in Orchidaceae are less frequent in the COL, FD and SOC1 gene lineages, which points to a retention of key functions under strong purifying selection in essential signaling factors. We also identified changes in the protein sequences after such duplications, variation in the evolutionary rates of resulting paralogous clades and targeted expression of isolated homologs in different orchids. Interestingly, vernalization-response genes like VERNALIZATION1 (VRN1) and FLOWERING LOCUS C (FLC) are completely lacking in orchids, or alternatively are reduced in number, as is the case of VERNALIZATION2/GHD7 (VRN2). Our findings point to non-canonical factors sensing temperature changes in orchids during reproductive transition. Expression data of key factors gathered from Elleanthus auratiacus, a terrestrial orchid in high Andean mountains allow us to characterize which copies are actually active during flowering. Altogether, our data lays down a comprehensive framework to assess gene function of a restricted number of homologs identified more likely playing key roles during the flowering transition, and the changes of the FGRN in neotropical orchids in comparison with temperate grasses.
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Affiliation(s)
- Yesenia Madrigal
- Facultad de Ciencias Exactas y Naturales, Instituto de Biología, Universidad de Antioquia, Medellín, Colombia
| | - Juan F Alzate
- Facultad de Medicina, Centro Nacional de Secuenciación Genómica, Sede de Investigación Universitaria, Universidad de Antioquia, Medellín, Colombia
| | - Natalia Pabón-Mora
- Facultad de Ciencias Exactas y Naturales, Instituto de Biología, Universidad de Antioquia, Medellín, Colombia.
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Yang Z, Zhao M, Zhang X, Gu L, Li J, Ming F, Wang M, Wang Z. MIR396-GRF/GIF enhances in planta shoot regeneration of Dendrobium catenatum. BMC Genomics 2024; 25:543. [PMID: 38822270 PMCID: PMC11143658 DOI: 10.1186/s12864-024-10360-9] [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: 01/08/2024] [Accepted: 04/29/2024] [Indexed: 06/02/2024] Open
Abstract
Recent studies on co-transformation of the growth regulator, TaGRF4-GIF1 chimera (Growth Regulating Factor 4-GRF Interacting Factor 1), in cultivated wheat varieties (Triticum aestivum), showed improved regeneration efficiency, marking a significant breakthrough. Here, a simple and reproducible protocol using the GRF4-GIF1 chimera was established and tested in the medicinal orchid Dendrobium catenatum, a monocot orchid species. TaGRF4-GIF1 from T. aestivum and DcGRF4-GIF1 from D. catenatum were reconstructed, with the chimeras significantly enhancing the regeneration efficiency of D. catenatum through in planta transformation. Further, mutating the microRNA396 (miR396) target sites in TaGRF4 and DcGRF4 improved regeneration efficiency. The target mimicry version of miR396 (MIM396) not only boosted shoot regeneration but also enhanced plant growth. Our methods revealed a powerful tool for the enhanced regeneration and genetic transformation of D. catenatum.
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Affiliation(s)
- Zhenyu Yang
- Shenzhen Key Laboratory for Orchid Conservation and Utilization, the National Orchid Conservation Center of China and the Orchid Conservation & Research Center of Shenzhen, Shenzhen, 518114, China
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization, the National Orchid Conservation Center of China and the Orchid Conservation & Research Center of Shenzhen, Shenzhen, 518114, China
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai, 200234, China
| | - Meili Zhao
- Shenzhen Key Laboratory for Orchid Conservation and Utilization, the National Orchid Conservation Center of China and the Orchid Conservation & Research Center of Shenzhen, Shenzhen, 518114, China
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization, the National Orchid Conservation Center of China and the Orchid Conservation & Research Center of Shenzhen, Shenzhen, 518114, China
| | - Xiaojie Zhang
- Shenzhen Key Laboratory for Orchid Conservation and Utilization, the National Orchid Conservation Center of China and the Orchid Conservation & Research Center of Shenzhen, Shenzhen, 518114, China
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization, the National Orchid Conservation Center of China and the Orchid Conservation & Research Center of Shenzhen, Shenzhen, 518114, China
- Xinjiang Key Laboratory of Grassland Resources and Ecology, College of Grassland Sciences, Xinjiang Agricultural University, Urumqi, 830052, China
| | - Lili Gu
- Xinjiang Key Laboratory of Grassland Resources and Ecology, College of Grassland Sciences, Xinjiang Agricultural University, Urumqi, 830052, China
| | - Jian Li
- Shenzhen Key Laboratory for Orchid Conservation and Utilization, the National Orchid Conservation Center of China and the Orchid Conservation & Research Center of Shenzhen, Shenzhen, 518114, China
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization, the National Orchid Conservation Center of China and the Orchid Conservation & Research Center of Shenzhen, Shenzhen, 518114, China
| | - Feng Ming
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai, 200234, China.
| | - Meina Wang
- Shenzhen Key Laboratory for Orchid Conservation and Utilization, the National Orchid Conservation Center of China and the Orchid Conservation & Research Center of Shenzhen, Shenzhen, 518114, China.
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization, the National Orchid Conservation Center of China and the Orchid Conservation & Research Center of Shenzhen, Shenzhen, 518114, China.
| | - Zhicai Wang
- Shenzhen Key Laboratory for Orchid Conservation and Utilization, the National Orchid Conservation Center of China and the Orchid Conservation & Research Center of Shenzhen, Shenzhen, 518114, China.
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization, the National Orchid Conservation Center of China and the Orchid Conservation & Research Center of Shenzhen, Shenzhen, 518114, China.
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Lu HC, Huang CW, Mimura T, Sukma D, Chan MT. Temperature-Regulated Flowering Locus T-Like Gene Coordinates the Spike Initiation in Phalaenopsis Orchid. PLANT & CELL PHYSIOLOGY 2024; 65:405-419. [PMID: 38153763 DOI: 10.1093/pcp/pcad166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 12/18/2023] [Accepted: 12/20/2023] [Indexed: 12/29/2023]
Abstract
Phalaenopsis aphrodite can be induced to initiate spike growth and flowering by exposure to low ambient temperatures. However, the factors and mechanisms responsible for spike initiation in P. aphrodite remain largely unknown. In this study, we show that a repressor Flowing Locus T-like (FTL) gene, FTL, can act as a negative regulator of spike initiation in P. aphrodite. The mRNA transcripts of PaFTL are consistently high during high ambient temperature, thereby preventing premature spike initiation. However, during low ambient temperature, PaFTL expression falls while FT expression increases, allowing for spike initiation. Knock-down of PaFTL expression through virus-inducing gene silencing promoted spike initiation at 30/28°C. Moreover, PaFTL interacts with FLOWERING LOCUS D in a similar manner to FT to regulate downstream flowering initiation genes. Transgenic P. aphrodite plants exhibiting high expression of PaFTL do not undergo spike initiation, even when exposed to low ambient temperatures. These findings shed light on the flowering mechanisms in Phalaenopsis and provide new insights into how perennial plants govern spike initiation in response to temperature cues.
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Affiliation(s)
- Hsiang-Chia Lu
- Academia Sinica Biotechnology Center in Southern Taiwan, Agricultural Biotechnology Research Center, Academia Sinica, No. 100, Sec. 1, Guiren 13th Rd., Guiren Dist., Tainan 741, Taiwan
| | - Chiao-Wen Huang
- Academia Sinica Biotechnology Center in Southern Taiwan, Agricultural Biotechnology Research Center, Academia Sinica, No. 100, Sec. 1, Guiren 13th Rd., Guiren Dist., Tainan 741, Taiwan
| | - Tetsuro Mimura
- Graduate Program of Translational Agricultural Sciences, National Cheng Kung University and Academia Sinica, No. 1, Daxue Rd., East Dist., Taiwan 70101, Taiwan
| | - Dewi Sukma
- Department of Agronomy & Horticulture, Faculty of Agriculture, IPB University, Jl. Meranti, Dramaga Campus, Bogor, West Java 16680, Indonesia
| | - Ming-Tsair Chan
- Academia Sinica Biotechnology Center in Southern Taiwan, Agricultural Biotechnology Research Center, Academia Sinica, No. 100, Sec. 1, Guiren 13th Rd., Guiren Dist., Tainan 741, Taiwan
- Graduate Program of Translational Agricultural Sciences, National Cheng Kung University and Academia Sinica, No. 1, Daxue Rd., East Dist., Taiwan 70101, Taiwan
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Iiyama CM, Vilcherrez-Atoche JA, Germanà MA, Vendrame WA, Cardoso JC. Breeding of ornamental orchids with focus on Phalaenopsis: current approaches, tools, and challenges for this century. Heredity (Edinb) 2024; 132:163-178. [PMID: 38302667 PMCID: PMC10997592 DOI: 10.1038/s41437-024-00671-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 01/09/2024] [Accepted: 01/11/2024] [Indexed: 02/03/2024] Open
Abstract
Ornamental orchid breeding programs have been conducted to develop commercially valuable cultivars with improved characteristics of commercial interest, such as size, flower color, pattern, shape, and resistance to pathogens. Conventional breeding, including sexual hybridization followed by selection of desirable characteristics in plants, has so far been the main method for ornamental breeding, but other techniques, including mutation induction by polyploidization and gamma irradiation, and biotechnological techniques, such as genetic transformation, have also been studied and used in ornamental breeding programs. Orchids are one of the most commercially important families in floriculture industry, having very particular reproductive biology characteristics and being a well-studied group of ornamentals in terms of genetic improvement. The present review focuses on the conventional and biotechnological techniques and approaches specially employed in breeding Phalaenopsis orchids, the genus with highest worldwide importance as an ornamental orchid, highlighting the main limitations and strengths of the approaches. Furthermore, new opportunities and future prospects for ornamental breeding in the CRISPR/Cas9 genome editing era are also discussed. We conclude that conventional hybridization remains the most used method to obtain new cultivars in orchids. However, the emergence of the first biotechnology-derived cultivars, as well as the new biotechnological tools available, such as CRISPR-Cas9, rekindled the full potential of biotechnology approaches and their importance for improve ornamental orchid breeding programs.
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Affiliation(s)
- Carla Midori Iiyama
- Laboratory of Plant Physiology and Tissue Culture, Department of Biotechnology, Plant and Animal Production, Centro de Ciências Agrárias, Universidade Federal de São Carlos (CCA/UFSCar), Rodovia Anhanguera, km 174, CEP13600-970, Araras, SP, Brazil.
- Graduate Program in Plant Production and Associated Bioprocesses, CCA/UFSCar, Araras, Brazil.
| | - Joe Abdul Vilcherrez-Atoche
- Laboratory of Plant Physiology and Tissue Culture, Department of Biotechnology, Plant and Animal Production, Centro de Ciências Agrárias, Universidade Federal de São Carlos (CCA/UFSCar), Rodovia Anhanguera, km 174, CEP13600-970, Araras, SP, Brazil
- Graduate Program in Plant Production and Associated Bioprocesses, CCA/UFSCar, Araras, Brazil
| | - Maria Antonietta Germanà
- Dipartimento Scienze Agrarie, Alimentari e Forestali (SAAF), Università degli Studi di Palermo, Palermo, Italy
| | - Wagner Aparecido Vendrame
- Environmental Horticulture Department, University of Florida, 2550 Hull Rd., Gainesville, FL, 32611, USA
| | - Jean Carlos Cardoso
- Laboratory of Plant Physiology and Tissue Culture, Department of Biotechnology, Plant and Animal Production, Centro de Ciências Agrárias, Universidade Federal de São Carlos (CCA/UFSCar), Rodovia Anhanguera, km 174, CEP13600-970, Araras, SP, Brazil.
- Graduate Program in Plant Production and Associated Bioprocesses, CCA/UFSCar, Araras, Brazil.
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Wei X, Yuan M, Zheng BQ, Zhou L, Wang Y. Genome-wide identification and characterization of TCP gene family in Dendrobium nobile and their role in perianth development. FRONTIERS IN PLANT SCIENCE 2024; 15:1352119. [PMID: 38375086 PMCID: PMC10875090 DOI: 10.3389/fpls.2024.1352119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 01/22/2024] [Indexed: 02/21/2024]
Abstract
TCP is a widely distributed, essential plant transcription factor that regulates plant growth and development. An in-depth study of TCP genes in Dendrobium nobile, a crucial parent in genetic breeding and an excellent model material to explore perianth development in Dendrobium, has not been conducted. We identified 23 DnTCP genes unevenly distributed across 19 chromosomes and classified them as Class I PCF (12 members), Class II: CIN (10 members), and CYC/TB1 (1 member) based on the conserved domain and phylogenetic analysis. Most DnTCPs in the same subclade had similar gene and motif structures. Segmental duplication was the predominant duplication event for TCP genes, and no tandem duplication was observed. Seven genes in the CIN subclade had potential miR319 and -159 target sites. Cis-acting element analysis showed that most DnTCP genes contained many developmental stress-, light-, and phytohormone-responsive elements in their promoter regions. Distinct expression patterns were observed among the 23 DnTCP genes, suggesting that these genes have diverse regulatory roles at different stages of perianth development or in different organs. For instance, DnTCP4 and DnTCP18 play a role in early perianth development, and DnTCP5 and DnTCP10 are significantly expressed during late perianth development. DnTCP17, 20, 21, and 22 are the most likely to be involved in perianth and leaf development. DnTCP11 was significantly expressed in the gynandrium. Specially, MADS-specific binding sites were present in most DnTCP genes putative promoters, and two Class I DnTCPs were in the nucleus and interacted with each other or with the MADS-box. The interactions between TCP and the MADS-box have been described for the first time in orchids, which broadens our understanding of the regulatory network of TCP involved in perianth development in orchids.
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Affiliation(s)
| | | | | | | | - Yan Wang
- State Key Laboratory of Tree Genetics and Breeding; Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
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Jia P, Wang Y, Sharif R, Dong QL, Liu Y, Luan HA, Zhang XM, Guo SP, Qi GH. KNOTTED1-like homeobox (KNOX) transcription factors - Hubs in a plethora of networks: A review. Int J Biol Macromol 2023; 253:126878. [PMID: 37703987 DOI: 10.1016/j.ijbiomac.2023.126878] [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: 07/05/2023] [Revised: 09/09/2023] [Accepted: 09/10/2023] [Indexed: 09/15/2023]
Abstract
KNOX (KNOTTED1-like HOMEOBOX) belongs to a class of important homeobox genes, which encode the homeodomain proteins binding to the specific element of target genes, and widely participate in plant development. Advancements in genetics and molecular biology research generate a large amount of information about KNOX genes in model and non-model plants, and their functions in different developmental backgrounds are gradually becoming clear. In this review, we summarize the known and presumed functions of the KNOX gene in plants, focusing on horticultural plants and crops. The classification and structural characteristics, expression characteristics and regulation, interacting protein factors, functions, and mechanisms of KNOX genes are systematically described. Further, the current research gaps and perspectives were discussed. These comprehensive data can provide a reference for the directional improvement of agronomic traits through KNOX gene regulation.
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Affiliation(s)
- Peng Jia
- College of Forestry, Hebei Agricultural University, Baoding 071000, China.
| | - Yuan Wang
- State Key Laboratory of North China Crop Improvement and Regulation, Hebei Agricultural University, Baoding 071000, China
| | - Rahat Sharif
- Department of Horticulture, School of Horticulture and Landscape, Yangzhou University, Yangzhou 225009, China
| | - Qing-Long Dong
- College of Forestry, Hebei Agricultural University, Baoding 071000, China
| | - Yang Liu
- College of Forestry, Hebei Agricultural University, Baoding 071000, China
| | - Hao-An Luan
- College of Forestry, Hebei Agricultural University, Baoding 071000, China
| | - Xue-Mei Zhang
- College of Forestry, Hebei Agricultural University, Baoding 071000, China
| | - Sup-Ping Guo
- College of Forestry, Hebei Agricultural University, Baoding 071000, China
| | - Guo-Hui Qi
- College of Forestry, Hebei Agricultural University, Baoding 071000, China.
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Zhao X, Li Y, Zhang MM, He X, Ahmad S, Lan S, Liu ZJ. Research advances on the gene regulation of floral development and color in orchids. Gene 2023; 888:147751. [PMID: 37657689 DOI: 10.1016/j.gene.2023.147751] [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: 06/28/2023] [Revised: 08/08/2023] [Accepted: 08/30/2023] [Indexed: 09/03/2023]
Abstract
Orchidaceae is one of the largest monocotyledon families and contributes significantly to worldwide biodiversity, with value in the fields of landscaping, medicine, and ecology. The diverse phenotypes and vibrant colors of orchid floral organs make them excellent research objects for investigating flower development and pigmentation. In recent years, a number of orchid genomes have been published, laying the molecular foundation for revealing flower development and color presentation. In this article, we review transcription factors, the structural genes responsible for the floral pigment synthesis pathways, the molecular mechanisms of flower morphogenesis, and the potential relationship between flower type and flower color. This study provides a theoretical reference for the research on molecular mechanisms related to flower morphogenesis and color presentation, genetic improvement, and new variety creation in orchids.
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Affiliation(s)
- Xuewei Zhao
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yuanyuan Li
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Meng-Meng Zhang
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Xin He
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Sagheer Ahmad
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Siren Lan
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Zhong-Jian Liu
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
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Jiang L, Ren Y, Jiang Y, Hu S, Wu J, Wang G. Characterization of NF-Y gene family and their expression and interaction analysis in Phalaenopsis orchid. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 204:108143. [PMID: 37913748 DOI: 10.1016/j.plaphy.2023.108143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 10/19/2023] [Accepted: 10/24/2023] [Indexed: 11/03/2023]
Abstract
The complex of Nuclear Factor Ys (NF-Ys), a family of heterotrimeric transcription factors composed of three unique subunits (NF-YA, NF-YB, and NF-YC), binds to the CCAAT box of eukaryotic promoters to activate or repress transcription of the downstream genes involved into various biological processes in plants. However, the systematic characterization of NF-Y gene family has not been elucidated in Phalaenopsis. A total of 24 NF-Y subunits (4 NF-YA, 9 NF-YB, and 11 NF-YC subunits) were identified in Phalaenopsis genome, whose exon/intron structures were highly differentiated among the PhNF-Y subunits. The distribution of motifs between coding regions of PhNF-YA and PhNF-YB/C was distinct. Segmental and tandem duplication events among paralogous PhNF-Ys were occurred. Six pairs of orthologous NF-Ys from Phalaenopsis and Arabidopsis and five pairs of orthologous NF-Ys from Phalaenopsis and rice involved in the phylogenetic gene synteny were identified. The various cis-elements being responsive to low-temperature, drought and ABA were distributed in the promoters of PhNF-Ys. qRT-PCR analysis indicated all of PhNF-Ys displayed the spatial specificity of expression in different tissues. Moreover, the expression levels of multiple PhNF-Ys significantly changed responding to low-temperature and ABA treatment. Yeast two hybrid and bimolecular fluorescence complementation assays approved the interaction of PhNF-YA1/3 with PhNF-YB6/PhNF-YC7, respectively, as well as PhNF-YB6 with PhNF-YC7. PhNF-YA1/3, PhNF-YB6, and PhNF-YC7 proteins were all localized in the nucleus. Further, transient overexpression of PhNF-YB6 and PhNF-YC7 promoted PhFT3 and repressed PhSVP expression in Phalaenopsis. These findings will facilitate to explore the role of PhNF-Ys in floral transition in Phalaenopsis orchid.
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Affiliation(s)
- Li Jiang
- Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of Biology of Ornamental Plants in East China, National Forestry and Grassland Administration, Department of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yuepeng Ren
- Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of Biology of Ornamental Plants in East China, National Forestry and Grassland Administration, Department of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yifan Jiang
- Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of Biology of Ornamental Plants in East China, National Forestry and Grassland Administration, Department of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Shasha Hu
- Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of Biology of Ornamental Plants in East China, National Forestry and Grassland Administration, Department of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Jiayi Wu
- Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of Biology of Ornamental Plants in East China, National Forestry and Grassland Administration, Department of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Guangdong Wang
- Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of Biology of Ornamental Plants in East China, National Forestry and Grassland Administration, Department of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China.
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10
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Zhao X, Zhang M, He X, Zheng Q, Huang Y, Li Y, Ahmad S, Liu D, Lan S, Liu Z. Genome-Wide Identification and Expression Analysis of the SPL Gene Family in Three Orchids. Int J Mol Sci 2023; 24:10039. [PMID: 37373185 DOI: 10.3390/ijms241210039] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 05/29/2023] [Accepted: 06/10/2023] [Indexed: 06/29/2023] Open
Abstract
SPL transcription factors regulate important processes such as plant growth and development, metabolic regulation, and abiotic stress. They play crucial roles in the development of flower organs. However, little is known about the characteristics and functions of the SPLs in the Orchidaceae. In this study, Cymbidium goeringii Rchb. f., Dendrobium chrysotoxum Lindl., and Gastrodia elata BI. were used as research objects. The SPL gene family of these orchids was analyzed on a genome-wide scale, and their physicochemical properties, phylogenetic relationships, gene structures, and expression patterns were studied. Transcriptome and qRT-PCR methods were combined to investigate the regulatory effect of SPLs on the development of flower organs during the flowering process (bud, initial bloom, and full bloom). This study identifies a total of 43 SPLs from C. goeringii (16), D. chrysotoxum (17), and G. elata (10) and divides them into eight subfamilies according to the phylogenetic tree. Most SPL proteins contained conserved SBP domains and complex gene structures; half of the genes had introns longer than 10 kb. The largest number and variety of cis-acting elements associated with light reactions were enriched, accounting for about 45% of the total (444/985); 13/43 SPLs contain response elements of miRNA156. GO enrichment analysis showed that the functions of most SPLs were mainly enriched in the development of plant flower organs and stems. In addition, expression patterns and qRT-PCR analysis suggested the involvement of SPL genes in the regulation of flower organ development in orchids. There was little change in the expression of the CgoSPL in C. goeringii, but DchSPL9 and GelSPL2 showed significant expression during the flowering process of D. chrysotoxum and G. elata, respectively. In summary, this paper provides a reference for exploring the regulation of the SPL gene family in orchids.
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Affiliation(s)
- Xuewei Zhao
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization, College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Mengmeng Zhang
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization, College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Xin He
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization, College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Qinyao Zheng
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization, College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Ye Huang
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization, College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yuanyuan Li
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization, College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Sagheer Ahmad
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization, College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Dingkun Liu
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization, College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Siren Lan
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization, College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Zhongjian Liu
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization, College of Landscape Architecture and Art, Fujian Agriculture and Forestry University, Fuzhou 350002, China
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11
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Suputri NPAEO, Prasojo IS, Prabowo LAT, Purwestri YA, Semiarti E. Identification of early flowering mutant gene in Phalaenopsis amabilis (L.) Blume for sgRNA construction in CRISPR/Cas9 genome editing system. BRAZ J BIOL 2023; 84:e268133. [PMID: 37283391 DOI: 10.1590/1519-6984.268133] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 04/12/2023] [Indexed: 06/08/2023] Open
Abstract
Phalaenopsis amabilis (L.) Blume commonly called Moth Orchid (Orchidaceae) is a natural orchid species designated as the National Flower of Indonesia for its beautiful flower shape and long-lasting flowering period. Basically, P. amabilis has a long vegetative phase that cause late flowering, about 2 to 3 years for flowering, hence a method to shorten vegetative period is desired. The latest technological approach that can be used to accelerate flowering of P. amabilis is the CRISPR/Cas9 genome editing method to inactivate the GAI (Gibberellic Acid Insensitive) gene as a mutant gene that can accelerate the regulation of FLOWERING TIME (FT) genes flowering biosynthesis pathway. The approach that needs to be taken is to silence the GAI gene with a knockout system which begins with identifying and characterizing the GAI target gene in the P. amabilis which will be used as a single guide RNA. CRISPR/Cas9 mediated knockout efficiency is highly dependent on the properties of the sgRNA used. SgRNA consists of a target sequence, determining its specificity performance. We executed phylogenetic clustering for the PaGAI protein with closely related orchid species such as Dendrobium capra, Dendrobium cultivars and Cymbidium sinensis. SWISS-Model as tool webserver for protein structure homology modeling. Results show that P. amabilis has a specific domain with the occurrence of point mutations in the two conservative domains. Therefore, a single guide RNA reconstruction needs to be implemented.
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Affiliation(s)
- N P A E O Suputri
- Universitas Gadjah Mada, Faculty of Biology, Department of Tropical Biology, Yogyakarta, Special Region of Yogyakarta, Indonesia
| | - I S Prasojo
- Universitas Gadjah Mada, Faculty of Biology, Department of Tropical Biology, Yogyakarta, Special Region of Yogyakarta, Indonesia
| | - L A T Prabowo
- Universitas Gadjah Mada, Faculty of Biology, Department of Tropical Biology, Yogyakarta, Special Region of Yogyakarta, Indonesia
| | - Y A Purwestri
- Universitas Gadjah Mada, Faculty of Biology, Department of Tropical Biology, Yogyakarta, Special Region of Yogyakarta, Indonesia
| | - E Semiarti
- Universitas Gadjah Mada, Faculty of Biology, Department of Tropical Biology, Yogyakarta, Special Region of Yogyakarta, Indonesia
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12
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Artuso S, Gamisch A, Staedler YM, Schönenberger J, Comes HP. Evidence for an evo-devo-derived hypothesis on three-dimensional flower shape modularity in a tropical orchid clade. Evolution 2022; 76:2587-2604. [PMID: 36128635 PMCID: PMC9828045 DOI: 10.1111/evo.14621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 08/21/2022] [Accepted: 08/26/2022] [Indexed: 01/22/2023]
Abstract
Covarying suites of phenotypic traits, or modules, are increasingly recognized to promote morphological evolution. However, information on how modularity influences flower diversity is rare and lacking for Orchidaceae. Here, we combine high-resolution X-ray computed tomography scanning with three-dimensional geometric morphometrics and phylogenetic comparative methods to test various hypotheses about three-dimensional patterns of flower evolutionary modularity in Malagasy Bulbophyllum orchids and examine rates and modes of module evolution. Based on the four evolutionary modules identified (i.e., sepals, lateral petals, labellum + column-foot, and column-part), our data support the hypothesis that both genetic-developmental and functional adaptive factors shaped evolutionary flower trait covariation in these tropical orchids. In line with "evo-devo" studies, we also find that the labellum evolved independently from the rest of the petal whorl. Finally, we show that modules evolved with different rates, and either in a neutral fashion (only column-part) or under selective constraints, as likely imposed by pollinators. Overall, this study supports current views that modular units can enhance the range and rate of morphological evolution.
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Affiliation(s)
- Silvia Artuso
- Department of Environment and BiodiversityUniversity of SalzburgSalzburg5020Austria
| | - Alexander Gamisch
- Department of Environment and BiodiversityUniversity of SalzburgSalzburg5020Austria
| | - Yannick M. Staedler
- Department of Botany and Biodiversity ResearchUniversity of ViennaVienna1030Austria
| | - Jürg Schönenberger
- Department of Botany and Biodiversity ResearchUniversity of ViennaVienna1030Austria
| | - Hans Peter Comes
- Department of Environment and BiodiversityUniversity of SalzburgSalzburg5020Austria
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13
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Zhang D, Zhao XW, Li YY, Ke SJ, Yin WL, Lan S, Liu ZJ. Advances and prospects of orchid research and industrialization. HORTICULTURE RESEARCH 2022; 9:uhac220. [PMID: 36479582 PMCID: PMC9720451 DOI: 10.1093/hr/uhac220] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 09/22/2022] [Indexed: 06/17/2023]
Abstract
Orchidaceae is one of the largest, most diverse families in angiosperms with significant ecological and economical values. Orchids have long fascinated scientists by their complex life histories, exquisite floral morphology and pollination syndromes that exhibit exclusive specializations, more than any other plants on Earth. These intrinsic factors together with human influences also make it a keystone group in biodiversity conservation. The advent of sequencing technologies and transgenic techniques represents a quantum leap in orchid research, enabling molecular approaches to be employed to resolve the historically interesting puzzles in orchid basic and applied biology. To date, 16 different orchid genomes covering four subfamilies (Apostasioideae, Vanilloideae, Epidendroideae, and Orchidoideae) have been released. These genome projects have given rise to massive data that greatly empowers the studies pertaining to key innovations and evolutionary mechanisms for the breadth of orchid species. The extensive exploration of transcriptomics, comparative genomics, and recent advances in gene engineering have linked important traits of orchids with a multiplicity of gene families and their regulating networks, providing great potential for genetic enhancement and improvement. In this review, we summarize the progress and achievement in fundamental research and industrialized application of orchids with a particular focus on molecular tools, and make future prospects of orchid molecular breeding and post-genomic research, providing a comprehensive assemblage of state of the art knowledge in orchid research and industrialization.
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Affiliation(s)
- Diyang Zhang
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Xue-Wei Zhao
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yuan-Yuan Li
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Shi-Jie Ke
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Wei-Lun Yin
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Siren Lan
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Zhong-Jian Liu
- Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
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14
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Hui W, Fan J, Liu X, Zhao F, Saba T, Wang J, Wu A, Zhang X, Zhang J, Zhong Y, Chen G, Gong W. Integrated transcriptome and plant growth substance profiles to identify the regulatory factors involved in floral sex differentiation in Zanthoxylum armatum DC. FRONTIERS IN PLANT SCIENCE 2022; 13:976338. [PMID: 36119602 PMCID: PMC9479546 DOI: 10.3389/fpls.2022.976338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 08/03/2022] [Indexed: 06/15/2023]
Abstract
Zanthoxylum armatum is a prominent plant for food industries. Its male flowers often occur in gynogenesis plants; however, the potential mechanism remains poorly understood. Herein, a total of 26 floral sex differentiation stages were observed to select four vital phases to reveal key factors by using RNA-seq, phytohormones and carbohydrates investigation. The results showed that a selective abortion of stamen or pistil primordia could result in the floral sex differentiation in Z. armatum. Carbohydrates might collaborate with cytokinin to effect the male floral differentiation, whereas female floral differentiation was involved in SA, GA1, and ABA biosynthesis and signal transduction pathways. Meanwhile, these endogenous regulators associated with reproductive growth might be integrated into ABCDE model to regulate the floral organ differentiation in Z. armatum. Furthermore, the 21 crucial candidates were identified in co-expression network, which would contribute to uncovering their roles in floral sex differentiation of Z. armatum in further studies. To the best of our knowledge, this study was the first comprehensive investigation to link floral sex differentiation with multi-level endogenous regulatory factors in Z. armatum. It also provided new insights to explore the regulatory mechanism of floral sex differentiation, which would be benefited to cultivate high-yield varieties in Z. armatum.
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Affiliation(s)
- Wenkai Hui
- Key Laboratory of Ecological Forestry Engineering of Sichuan Province, College of Forestry, Sichuan Agricultural University, Chengdu, China
| | - Jiangtao Fan
- Key Laboratory of Ecological Forestry Engineering of Sichuan Province, College of Forestry, Sichuan Agricultural University, Chengdu, China
| | - Xianzhi Liu
- Key Laboratory of Ecological Forestry Engineering of Sichuan Province, College of Forestry, Sichuan Agricultural University, Chengdu, China
| | - Feiyan Zhao
- Key Laboratory of Ecological Forestry Engineering of Sichuan Province, College of Forestry, Sichuan Agricultural University, Chengdu, China
| | - Tasheen Saba
- Key Laboratory of Ecological Forestry Engineering of Sichuan Province, College of Forestry, Sichuan Agricultural University, Chengdu, China
| | - Jingyan Wang
- Key Laboratory of Ecological Forestry Engineering of Sichuan Province, College of Forestry, Sichuan Agricultural University, Chengdu, China
| | - Aimin Wu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
| | - Xuebin Zhang
- State Key Laboratory of Cotton Biology, Department of Biology, Institute of Plant Stress Biology, Henan University, Kaifeng, China
| | - Junli Zhang
- State Key Laboratory of Cotton Biology, Department of Biology, Institute of Plant Stress Biology, Henan University, Kaifeng, China
| | - Yu Zhong
- Key Laboratory of Ecological Forestry Engineering of Sichuan Province, College of Forestry, Sichuan Agricultural University, Chengdu, China
| | - Gang Chen
- Key Laboratory of Ecological Forestry Engineering of Sichuan Province, College of Forestry, Sichuan Agricultural University, Chengdu, China
| | - Wei Gong
- Key Laboratory of Ecological Forestry Engineering of Sichuan Province, College of Forestry, Sichuan Agricultural University, Chengdu, China
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15
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Li Y, Zhang B, Yu H. Molecular genetic insights into orchid reproductive development. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:1841-1852. [PMID: 35104310 DOI: 10.1093/jxb/erac016] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 01/17/2022] [Indexed: 06/14/2023]
Abstract
Orchids are members of the Orchidaceae, one of the largest families of flowering plants, and occupy a wide range of ecological habitats with highly specialized reproductive features. They exhibit unique developmental characteristics, such as generation of storage organs during flowering and spectacular floral morphological features, which contribute to their reproductive success in different habitats in response to various environmental cues. Here we review current understanding of the molecular genetic basis of orchid reproductive development, including flowering time control, floral patterning and flower color, with a focus on the orchid genes that have been functionally validated in plants. Furthermore, we summarize recent progress in annotating orchid genomes, and discuss how integration of high-quality orchid genome sequences with other advanced tools, such as the ever-improving multi-omics approaches and genome editing technologies as well as orchid-specific technical platforms, could open up new avenues to elucidate the molecular genetic basis of highly specialized reproductive organs and strategies in orchids.
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Affiliation(s)
- Yan Li
- Department of Biological Sciences, National University of Singapore, Singapore
| | - Bin Zhang
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore
| | - Hao Yu
- Department of Biological Sciences, National University of Singapore, Singapore
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore
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16
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Tejeda-Sartorius O, Soto-Hernández RM, San Miguel-Chávez R, Trejo-Téllez LI, Caamal-Velázquez H. Endogenous Hormone Profile and Sugars Display Differential Distribution in Leaves and Pseudobulbs of Laelia anceps Plants Induced and Non-Induced to Flowering by Exogenous Gibberellic Acid. PLANTS 2022; 11:plants11070845. [PMID: 35406825 PMCID: PMC9003143 DOI: 10.3390/plants11070845] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 02/15/2022] [Accepted: 03/17/2022] [Indexed: 12/04/2022]
Abstract
A profile of endogenous hormones and sugars in leaves and pseudobulbs of Laelia anceps subsp. anceps (Orchidaceae) plants induced and non-induced to flowering by the effect of different doses of exogenous gibberellic acid (GA3), considering the current and back growth structures (CGS and BGS), were investigated. A factorial experiment with five doses of GA3 and two growth structures was designed. Adult plants with undifferentiated vegetative buds were selected and sprayed with doses of 0, 400, 600, 800, and 1000 mg GA3 L−1. The main results showed a strong interaction between GA3 dose and growth structures, which promoted the highest kinetin (KIN) concentration in CGS. Exogenous GA3 increased endogenous GA3 in leaves and pseudobulbs induced (I-Leaf and I-PSB) and non-induced (NI-Leaf and NI-PSB) to flowering. For sugar concentration, the 400 mg L−1 GA3 dose promotes significant interaction with the CGS in NI-PSB. In general, the hormone profile revealed opposite balances of endogenous hormone concentrations for KIN, zeatin (ZEA), trans-zeatin (T-ZEA), indoleacetic acid (IAA), indole-3-butyric acid (IBA) and GA3, not only for growth structures but also for vegetative organs analyzed, depending on whether the plants were induced or not induced to flowering, with the highest concentration of endogenous hormones in pseudobulbs. Likewise, different sugar concentration balances were observed. These balances of both endogenous hormones and sugars are likely to be involved in the flowering of L. anceps.
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Affiliation(s)
- Olga Tejeda-Sartorius
- Campus Montecillo, College of Postgraduates in Agricultural Sciences, Texcoco 56230, Mexico; (R.M.S.-H.); (R.S.M.-C.); (L.I.T.-T.)
- Correspondence:
| | - Ramón Marcos Soto-Hernández
- Campus Montecillo, College of Postgraduates in Agricultural Sciences, Texcoco 56230, Mexico; (R.M.S.-H.); (R.S.M.-C.); (L.I.T.-T.)
| | - Rubén San Miguel-Chávez
- Campus Montecillo, College of Postgraduates in Agricultural Sciences, Texcoco 56230, Mexico; (R.M.S.-H.); (R.S.M.-C.); (L.I.T.-T.)
| | - Libia Iris Trejo-Téllez
- Campus Montecillo, College of Postgraduates in Agricultural Sciences, Texcoco 56230, Mexico; (R.M.S.-H.); (R.S.M.-C.); (L.I.T.-T.)
| | - Humberto Caamal-Velázquez
- Campus Campeche, College of Postgraduates in Agricultural Sciences, Champotón 24450, Campeche, Mexico;
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The Genetic and Hormonal Inducers of Continuous Flowering in Orchids: An Emerging View. Cells 2022; 11:cells11040657. [PMID: 35203310 PMCID: PMC8870070 DOI: 10.3390/cells11040657] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 02/09/2022] [Accepted: 02/11/2022] [Indexed: 02/07/2023] Open
Abstract
Orchids are the flowers of magnetic beauty. Vivid and attractive flowers with magnificent shapes make them the king of the floriculture industry. However, the long-awaited flowering is a drawback to their market success, and therefore, flowering time regulation is the key to studies about orchid flower development. Although there are some rare orchids with a continuous flowering pattern, the molecular regulatory mechanisms are yet to be elucidated to find applicable solutions to other orchid species. Multiple regulatory pathways, such as photoperiod, vernalization, circadian clock, temperature and hormonal pathways are thought to signalize flower timing using a group of floral integrators. This mini review, thus, organizes the current knowledge of floral time regulators to suggest future perspectives on the continuous flowering mechanism that may help to plan functional studies to induce flowering revolution in precious orchid species.
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18
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Jiang L, Jiang X, Li Y, Gao Y, Wang S, Ma Y, Wang G. FT-like paralogs are repressed by an SVP protein during the floral transition in Phalaenopsis orchid. PLANT CELL REPORTS 2022; 41:233-248. [PMID: 34713321 DOI: 10.1007/s00299-021-02805-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 10/14/2021] [Indexed: 06/13/2023]
Abstract
An SVP protein, PhSVP, bound to the CArG-boxes in the promoter regions of FT-like paralogs and repressed their expression, thus affecting the floral transition in Phalaenopsis orchid. Phalaenopsis is an important ornamental flower native to tropical rain forests. It usually reaches vegetative maturity after 4-5 leaves and, after a juvenile stage, forms a flower spike (inflorescence) from the axillary buds. The PEBP gene family encodes a phosphatidyl-ethanolamine-binding protein (PEBP) domain involved in regulating flowering and other aspects of plant development. Here, we identified eight PEBP family genes in Phalaenopsis and detected the expression patterns of seven of them in various organs. Among them, PhFT1 (Phalaenopsis hybrid FLOWERING LOCUS T1), PhFT3, PhFT5, and PhMFT (Phalaenopsis hybrid MOTHER OF FT AND TFL1) promoted flowering in transgenic Arabidopsis, while PhFT6 inhibited flowering. PhSVP (Phalaenopsis hybrid SHORT VEGETATIVE PHASE), an SVP protein that repressed flowering in Arabidopsis, bound to the CArG-boxes in the promoter regions of PhFT3, PhFT6, and PhMFT in a yeast one-hybrid assay. Additionally, dual-luciferase and transient expression assays showed that PhSVP significantly inhibits the expression of both PhFT3 and PhFT6. Together, our work provides a comprehensive understanding of the PhFT-like genes that can promote or repress flowering, and it suggests strategies for regulating the floral transition in Phalaenopsis that exploit the evolutionary versatility of PhFTs to respond to various signals stimuli.
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Affiliation(s)
- Li Jiang
- Department of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Xiaoxiao Jiang
- Department of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yanna Li
- Department of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yongxia Gao
- Department of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Shiyao Wang
- Department of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yuehua Ma
- Department of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Guangdong Wang
- Department of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China.
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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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20
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Ahmad S, Lu C, Gao J, Ren R, Wei Y, Wu J, Jin J, Zheng C, Zhu G, Yang F. Genetic insights into the regulatory pathways for continuous flowering in a unique orchid Arundina graminifolia. BMC PLANT BIOLOGY 2021; 21:587. [PMID: 34893019 PMCID: PMC8662845 DOI: 10.1186/s12870-021-03350-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 11/17/2021] [Indexed: 05/07/2023]
Abstract
BACKGROUND Manipulation of flowering time and frequency of blooming is key to enhancing the ornamental value of orchids. Arundina graminifolia is a unique orchid that flowers year round, although the molecular basis of this flowering pattern remains poorly understood. RESULTS We compared the A. graminifolia transcriptome across tissue types and floral developmental stages to elucidate important genetic regulators of flowering and hormones. Clustering analyses identified modules specific to floral transition and floral morphogenesis, providing a set of candidate regulators for the floral initiation and timing. Among candidate floral homeotic genes, the expression of two FT genes was positively correlated with flower development. Assessment of the endogenous hormone levels and qRT-PCR analysis of 32 pathway-responsive genes supported a role for the regulatory networks in floral bud control in A. graminifolia. Moreover, WGCNA showed that flowering control can be delineated by modules of coexpressed genes; especially, MEgreen presented group of genes specific to flowering. CONCLUSIONS Candidate gene selection coupled with hormonal regulators brings a robust source to understand the intricate molecular regulation of flowering in precious orchids.
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Affiliation(s)
- Sagheer Ahmad
- Guangdong Key Laboratory of Ornamental Plant Germplasm Innovation and Utilization, Environmental Horticulture Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640 People’s Republic of China
| | - Chuqiao Lu
- Guangdong Key Laboratory of Ornamental Plant Germplasm Innovation and Utilization, Environmental Horticulture Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640 People’s Republic of China
| | - Jie Gao
- Guangdong Key Laboratory of Ornamental Plant Germplasm Innovation and Utilization, Environmental Horticulture Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640 People’s Republic of China
| | - Rui Ren
- Guangdong Key Laboratory of Ornamental Plant Germplasm Innovation and Utilization, Environmental Horticulture Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640 People’s Republic of China
| | - Yonglu Wei
- Guangdong Key Laboratory of Ornamental Plant Germplasm Innovation and Utilization, Environmental Horticulture Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640 People’s Republic of China
| | - Jieqiu Wu
- Guangdong Key Laboratory of Ornamental Plant Germplasm Innovation and Utilization, Environmental Horticulture Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640 People’s Republic of China
| | - Jianpeng Jin
- Guangdong Key Laboratory of Ornamental Plant Germplasm Innovation and Utilization, Environmental Horticulture Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640 People’s Republic of China
| | - Chuanyuan Zheng
- Guangdong Key Laboratory of Ornamental Plant Germplasm Innovation and Utilization, Environmental Horticulture Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640 People’s Republic of China
| | - Genfa Zhu
- Guangdong Key Laboratory of Ornamental Plant Germplasm Innovation and Utilization, Environmental Horticulture Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640 People’s Republic of China
| | - Fengxi Yang
- Guangdong Key Laboratory of Ornamental Plant Germplasm Innovation and Utilization, Environmental Horticulture Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640 People’s Republic of China
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21
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Feng JQ, Xia Q, Zhang FP, Wang JH, Zhang SB. Is seasonal flowering time of Paphiopedilum species caused by differences in initial time of floral bud differentiation? AOB PLANTS 2021; 13:plab053. [PMID: 34646434 PMCID: PMC8501908 DOI: 10.1093/aobpla/plab053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Accepted: 08/18/2021] [Indexed: 06/02/2023]
Abstract
Members of the genus Paphiopedilum are world-famous for their large, colourful flowers, unique floral morphology and long floral lifespan. Most Paphiopedilum species bloom in spring or autumn. The control of flowering time is of great significance to the commercial production of floral crops, because it affects the sales and prices of flowers. However, the mechanism that regulates when Paphiopedilum species bloom is unclear. In the present study, floral bud initiation and development of P. micranthum (spring-flowering species with one flower per stalk), P. dianthum (autumn-flowering species with multiple flowers per stalk) and P. henryanum (autumn-flowering species with one flower per stalk) were investigated by morphological and anatomical methods. We divided Paphiopedilum floral bud differentiation into six phases: the initiation of differentiation, inflorescence primordium differentiation, flower primordium differentiation, sepal primordium differentiation, petal primordium differentiation and column primordium differentiation. We found that the timing of floral bud differentiation for the three species was synchronized when experiencing the same environment, while the period from initiation to flowering largely differed. In addition, initiation of floral bud differentiation in P. dianthum was earlier at a warmer environment. The difference in flowering time of three species was mainly caused by the duration of floral bud development, rather than the initiation time. The findings were of great significance for the cultivation and flowering regulation of Paphiopedilum species.
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Affiliation(s)
- Jing-Qiu Feng
- Key Laboratory of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qian Xia
- Key Laboratory of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China
- School of Life Sciences, Yunnan University, Kunming 650500, Yunnan, China
| | - Feng-Ping Zhang
- College of Traditional Chinese Medicine, Yunnan Key Laboratory of Dai and Yi Medicines, Yunnan University of Chinese Medicine, Kunming 650500, Yunnan, China
| | - Ji-Hua Wang
- Flower Research Institute of Yunnan Academy of Agricultural Sciences, Kunming 650205, Yunnan, China
| | - Shi-Bao Zhang
- Key Laboratory of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China
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22
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Li Z, Tang M, Luo D, Kashif MH, Cao S, Zhang W, Hu Y, Huang Z, Yue J, Li R, Chen P. Integrated Methylome and Transcriptome Analyses Reveal the Molecular Mechanism by Which DNA Methylation Regulates Kenaf Flowering. FRONTIERS IN PLANT SCIENCE 2021; 12:709030. [PMID: 34512693 PMCID: PMC8428968 DOI: 10.3389/fpls.2021.709030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 07/26/2021] [Indexed: 05/03/2023]
Abstract
DNA methylation regulates key biological processes in plants. In this study, kenaf seedlings were pretreated with the DNA methylation inhibitor 5-azacytidine (5-azaC) (at concentrations of 0, 100, 200, 400, and 600 μM), and the results showed that pretreatment with 200 μM 5-azaC promoted flowering most effectively. To elucidate the underlying mechanism, phytohormone, adenosine triphosphate (ATP), and starch contents were determined, and genome-wide DNA methylation and transcriptome analyses were performed on anthers pretreated with 200 μM 5-azaC (5-azaC200) or with no 5-azaC (control conditions; 5-azaC0). Biochemical analysis revealed that 5-azaC pretreatment significantly reduced indoleacetic acid (IAA) and gibberellic acid (GA) contents and significantly increased abscisic acid (ABA) and ATP contents. The starch contents significantly increased in response to 200 and 600 μM 5-azaC. Further genome-wide DNA methylation analysis revealed 451 differentially methylated genes (DMGs) with 209 up- and 242 downregulated genes. Transcriptome analysis showed 3,986 differentially expressed genes (DEGs), with 2,171 up- and 1,815 downregulated genes. Integrated genome-wide DNA methylation and transcriptome analyses revealed 72 genes that were both differentially methylated and differentially expressed. These genes, which included ARFs, PP2C, starch synthase, FLC, PIF1, AGL80, and WRKY32, are involved mainly in plant hormone signal transduction, starch and sucrose metabolism, and flowering regulation and may be involved in early flowering. This study serves as a reference and theoretical basis for kenaf production and provides insights into the effects of DNA methylation on plant growth and development.
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Affiliation(s)
- Zengqiang Li
- Key Laboratory of Plant Genetics and Breeding, College of Agriculture, Guangxi University, Nanning, China
| | - Meiqiong Tang
- Key Laboratory of Plant Genetics and Breeding, College of Agriculture, Guangxi University, Nanning, China
| | - Dengjie Luo
- Key Laboratory of Plant Genetics and Breeding, College of Agriculture, Guangxi University, Nanning, China
| | - Muhammad Haneef Kashif
- Key Laboratory of Plant Genetics and Breeding, College of Agriculture, Guangxi University, Nanning, China
| | - Shan Cao
- Key Laboratory of Plant Genetics and Breeding, College of Agriculture, Guangxi University, Nanning, China
| | - Wenxian Zhang
- Key Laboratory of Plant Genetics and Breeding, College of Agriculture, Guangxi University, Nanning, China
| | - Yali Hu
- Key Laboratory of Plant Genetics and Breeding, College of Agriculture, Guangxi University, Nanning, China
| | - Zhen Huang
- Key Laboratory of Plant Genetics and Breeding, College of Agriculture, Guangxi University, Nanning, China
| | - Jiao Yue
- Key Laboratory of Plant Genetics and Breeding, College of Agriculture, Guangxi University, Nanning, China
| | - Ru Li
- College of Life Science and Technology, Guangxi University, Nanning, China
| | - Peng Chen
- Key Laboratory of Plant Genetics and Breeding, College of Agriculture, Guangxi University, Nanning, China
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23
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van Tongerlo E, van Ieperen W, Dieleman JA, Marcelis LFM. Vegetative traits can predict flowering quality in Phalaenopsis orchids despite large genotypic variation in response to light and temperature. PLoS One 2021; 16:e0251405. [PMID: 33974639 PMCID: PMC8112652 DOI: 10.1371/journal.pone.0251405] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 04/27/2021] [Indexed: 11/19/2022] Open
Abstract
Phalaenopsis is an economically important horticultural ornamental, but its growth is slow and costly. The vegetative cultivation phase is long and required to ensure sufficient plant size. This is needed to develop high quality flowering plants. We studied the effects of temperature (27 or 31 °C) and light intensity (60 or 140 μmol m-2 s-1) on plant growth and development during the vegetative cultivation phase in two experiments, with respectively 19 and 14 genotypes. Furthermore, the after-effects of treatments applied during vegetative growth on flowering traits were determined. Increasing light intensity in the vegetative phase accelerated both vegetative plant growth and development. Increasing temperature accelerated vegetative leaf appearance rate, but strongly reduced plant and root biomass accumulation when temperatures were too high. Flowering was greatly affected by treatments applied during vegetative growth, and increased light and temperature increased number of flower spikes, and number of flowers and buds. Genotypic variation was large in Phalaenopsis, especially in traits related to flowering, thus care is needed when generalising results based on a limited number of cultivars. Plant biomass and number of leaves during vegetative growth were positively correlated with flowering quality. These traits can be used as an early predictor for flowering capacity and quality of the final product. Additionally, this knowledge can be used to improve selection of new cultivars.
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Affiliation(s)
- Evelien van Tongerlo
- Horticulture and Product Physiology, Department of Plant Sciences, Wageningen University & Research, Wageningen, The Netherlands
- * E-mail:
| | - Wim van Ieperen
- Horticulture and Product Physiology, Department of Plant Sciences, Wageningen University & Research, Wageningen, The Netherlands
| | - Janneke A. Dieleman
- Greenhouse Horticulture, Wageningen University & Research, Wageningen, The Netherlands
| | - Leo F. M. Marcelis
- Horticulture and Product Physiology, Department of Plant Sciences, Wageningen University & Research, Wageningen, The Netherlands
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24
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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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25
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Wang Y, Li Y, Yan X, Ding L, Shen L, Yu H. Characterization of C- and D-Class MADS-Box Genes in Orchids. PLANT PHYSIOLOGY 2020; 184:1469-1481. [PMID: 32900977 PMCID: PMC7608164 DOI: 10.1104/pp.20.00487] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 08/29/2020] [Indexed: 05/20/2023]
Abstract
Orchids (members of the Orchidaceae family) possess unique flower morphology and adaptive reproduction strategies. Although the mechanisms underlying their perianth development have been intensively studied, the molecular basis of reproductive organ development in orchids remains largely unknown. Here, we report the identification and functional characterization of two AGAMOUS (AG)-like MADS-box genes, Dendrobium 'Orchid' AG1 (DOAG1) and DOAG2, which are putative C- and D-class genes, respectively, from the orchid Dendrobium 'Chao Praya Smile'. Both DOAG1 and DOAG2 are highly expressed in the reproductive organ, known as the column, compared to perianth organs, while DOAG2 expression gradually increases in pace with pollination-induced ovule development and is localized in ovule primordia. Ectopic expression of DOAG1, but not DOAG2, rescues floral defects in the Arabidopsis (Arabidopsis thaliana) ag-4 mutant, including reiteration of stamenoid perianth organs in inner whorls and complete loss of carpels. Downregulation of DOAG1 and DOAG2 in orchids by artificial microRNA interference using l-Met sulfoximine selection-based gene transformation systems shows that both genes are essential for specifying reproductive organ identity, yet they, exert different roles in mediating floral meristem determinacy and ovule development, respectively, in Dendrobium spp. orchids. Notably, knockdown of DOAG1 and DOAG2 also affects perianth organ development in orchids. Our findings suggest that DOAG1 and DOAG2 not only act as evolutionarily conserved C- and D-class genes, respectively, in determining reproductive organ identity, but also play hitherto unknown roles in mediating perianth organ development in orchids.
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Affiliation(s)
- Yanwen Wang
- Department of Biological Sciences, National University of Singapore, Singapore 117543
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore 117604
| | - Yan Li
- Department of Biological Sciences, National University of Singapore, Singapore 117543
| | - Xiaojing Yan
- Department of Biological Sciences, National University of Singapore, Singapore 117543
| | - Lihua Ding
- Department of Biological Sciences, National University of Singapore, Singapore 117543
| | - Lisha Shen
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore 117604
| | - Hao Yu
- Department of Biological Sciences, National University of Singapore, Singapore 117543
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore 117604
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