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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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Tai Y, Zhang J, Chen Y, Yuan Y, Wang H, Yu L, Li S, Yang L, Jin Y. Establishment and validation of a callus tissue transformation system for German chamomile (Matricaria chamomilla L.). BMC PLANT BIOLOGY 2023; 23:659. [PMID: 38124039 PMCID: PMC10731808 DOI: 10.1186/s12870-023-04680-3] [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: 09/26/2023] [Accepted: 12/11/2023] [Indexed: 12/23/2023]
Abstract
BACKGROUND German chamomile (Matricaria chamomilla L.) is an important medicinal plant, and the essential oils in the flowers have various biological activities. Genetic transformation systems are important for plant quality improvement and molecular research. To the best of our knowledge, a genetic transformation system has not yet been reported for German chamomile. RESULTS In this study, we developed Agrobacterium-mediated transformation protocols for German chamomile callus tissues. This involved optimizing key parameters, such as hygromycin and cefotaxime concentrations, bacterial density, and infection and co-culture durations. We also performed gas chromatography-mass spectrometry analysis to identify volatile compounds in non-transgenic and transgenic callus and hairy root tissues. Furthermore, to compare and verify the callus transformation system of German chamomile, we transferred McFPS to the hairy roots of German chamomile. The results showed that the optimal conditions for Agrobacterium-mediated callus tissue transformation were as follows: explant, petiole; cefotaxime concentration, 300 mg/L; hygromycin concentration, 10 mg/L; and bacterial solution concentration, OD600 = 0.6; callus transformation efficiency was the highest when the co-culture time was 3 days. CONCLUSIONS Establishment of a high-efficiency callus transformation system will lay the foundation for gene function identification in German chamomile.
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Affiliation(s)
- Yuling Tai
- School of Life Science, Anhui Agricultural University, Hefei, 230036, People's Republic of China
| | - Jie Zhang
- School of Life Science, Anhui Agricultural University, Hefei, 230036, People's Republic of China
| | - Youhui Chen
- School of Life Science, Anhui Agricultural University, Hefei, 230036, People's Republic of China
| | - Yi Yuan
- School of Life Science, Anhui Agricultural University, Hefei, 230036, People's Republic of China.
| | - Honggang Wang
- School of Life Science, Anhui Agricultural University, Hefei, 230036, People's Republic of China
| | - Luyao Yu
- School of Life Science, Anhui Agricultural University, Hefei, 230036, People's Republic of China
| | - Shuangshuang Li
- School of Life Science, Anhui Agricultural University, Hefei, 230036, People's Republic of China
| | - Lu Yang
- School of Life Science, Anhui Agricultural University, Hefei, 230036, People's Republic of China
| | - Yifan Jin
- School of Life Science, Anhui Agricultural University, Hefei, 230036, People's Republic of China
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Ovcharenko OO, Rudas VA. Modern Approaches to Genetic Engineering in the Orchidaceae Family. CYTOL GENET+ 2023. [DOI: 10.3103/s0095452723020093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
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Chang L, Tzean Y, Hsin KT, Lin CY, Wang CN, Yeh HH. Stress associated proteins coordinate the activation of comprehensive antiviral immunity in Phalaenopsis orchids. THE NEW PHYTOLOGIST 2022; 233:145-155. [PMID: 34614215 DOI: 10.1111/nph.17776] [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: 04/28/2021] [Accepted: 09/20/2021] [Indexed: 06/13/2023]
Abstract
Viruses cause severe damage on crops, and identification of key gene(s) that can comprehensively activate antiviral immunity will provide insights for designing effective antiviral strategies. Salicylic acid (SA)-mediated antiviral immunity and RNA interference (RNAi) are two independently discovered antiviral pathways. Previously, we identified the orchid stress-associated protein (SAP), Pha13, which serves as a hub in SA-mediated antiviral immunity. As SAPs exist as a protein family, whether duplicated SAPs have redundant or distinctive functions in antiviral immunity remains elusive. We performed functional assays on orchid Pha21, a homolog of Pha13, using transient and transgenic approaches on orchid, Arabidopsis and Nicotiana benthamiana to overexpress and/or silence Pha21. The SA treatment induced the expression of both Pha13 and Pha21, whereas Pha21 was found to play a key role in the initiation of the RNAi pathway in Phalaenopsis orchids. We demonstrated that Pha21-mediated antiviral immunity and enhancement of the RNAi pathway is conserved between dicotyledons and monocotyledons. We provide new insight that orchid SAPs confer distinctive functions to coordinate both SA-signaling and RNAi for comprehensive activation of antiviral immunity, and this information will help us develop antiviral strategies on crops.
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Affiliation(s)
- Li Chang
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, 11529, Taiwan
| | - Yuh Tzean
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, 11529, Taiwan
| | - Kuan-Ting Hsin
- Department of Life Science, National Taiwan University, Taipei, 10617, Taiwan
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei, 10617, Taiwan
| | - Chia-Ying Lin
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, 11529, Taiwan
| | - Chun-Neng Wang
- Department of Life Science, National Taiwan University, Taipei, 10617, Taiwan
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei, 10617, Taiwan
| | - Hsin-Hung Yeh
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, 11529, Taiwan
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, 10617, Taiwan
- Institute of Biotechnology, National Taiwan University, Taipei, 10617, Taiwan
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Chen JC, Tong CG, Lin HY, Fang SC. Phalaenopsis LEAFY COTYLEDON1-Induced Somatic Embryonic Structures Are Morphologically Distinct From Protocorm-Like Bodies. FRONTIERS IN PLANT SCIENCE 2019; 10:1594. [PMID: 31850050 PMCID: PMC6896055 DOI: 10.3389/fpls.2019.01594] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 11/13/2019] [Indexed: 05/27/2023]
Abstract
Somatic embryogenesis is commonly used for clonal propagation of a wide variety of plant species. Induction of protocorm-like-bodies (PLBs), which are capable of developing into individual plants, is a routine tissue culture-based practice for micropropagation of orchid plants. Even though PLBs are often regarded as somatic embryos, our recent study provides molecular evidence to argue that PLBs are not derived from somatic embryogenesis. Here, we report and characterize the somatic embryonic tissues induced by Phalaenopsis aphrodite LEAFY COTYLEDON1 (PaLEC1) in Phalaenopsis equestris. We found that PaLEC1-induced somatic tissues are morphologically different from PLBs, supporting our molecular study that PLBs are not of somatic embryonic origin. The embryonic identity of PaLEC1-induced embryonic tissues was confirmed by expression of the embryonic-specific transcription factors FUSCA3 (FUS3) and ABSCISIC ACID INSENSITIVE3 (ABI3), and seed storage proteins 7S GLOBULIN and OLEOSIN. Moreover, PaLEC1-GFP protein was found to be associated with the Pa7S-1 and PaFUS3 promoters containing the CCAAT element, supporting that PaLEC1 directly regulates embryo-specific processes to activate the somatic embryonic program in P. equestris. Despite diverse embryonic structures, PaLEC1-GFP-induced embryonic structures are pluripotent and capable of generating new shoots. Our study resolves the long-term debate on the developmental identity of PLB and suggests that somatic embryogenesis may be a useful approach to clonally propagate orchid seedlings.
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Affiliation(s)
- Jhun-Chen Chen
- Biotechnology Center in Southern Taiwan, Academia Sinica, Tainan, Taiwan
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan
| | - Chii-Gong Tong
- Biotechnology Center in Southern Taiwan, Academia Sinica, Tainan, Taiwan
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan
| | - Hsiang-Yin Lin
- Biotechnology Center in Southern Taiwan, Academia Sinica, Tainan, Taiwan
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan
| | - Su-Chiung Fang
- Biotechnology Center in Southern Taiwan, Academia Sinica, Tainan, Taiwan
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan
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Teo ZWN, Zhou W, Shen L. Dissecting the Function of MADS-Box Transcription Factors in Orchid Reproductive Development. FRONTIERS IN PLANT SCIENCE 2019; 10:1474. [PMID: 31803211 PMCID: PMC6872546 DOI: 10.3389/fpls.2019.01474] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 10/23/2019] [Indexed: 05/20/2023]
Abstract
The orchid family (Orchidaceae) represents the second largest angiosperm family, having over 900 genera and 27,000 species in almost all over the world. Orchids have evolved a myriad of intriguing ways in order to survive extreme weather conditions, acquire nutrients, and attract pollinators for reproduction. The family of MADS-box transcriptional factors have been shown to be involved in the control of many developmental processes and responses to environmental stresses in eukaryotes. Several findings in different orchid species have elucidated that MADS-box genes play critical roles in the orchid growth and development. An in-depth understanding of their ecological adaptation will help to generate more interest among breeders and produce novel varieties for the floriculture industry. In this review, we summarize recent findings of MADS-box transcription factors in regulating various growth and developmental processes in orchids, in particular, the floral transition and floral patterning. We further discuss the prospects for the future directions in light of new genome resources and gene editing technologies that could be applied in orchid research and breeding.
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Affiliation(s)
- Zhi Wei Norman Teo
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore, Singapore
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore
| | - Wei Zhou
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore, Singapore
| | - Lisha Shen
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore, Singapore
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Wang SL, Viswanath KK, Tong CG, An HR, Jang S, Chen FC. Floral Induction and Flower Development of Orchids. FRONTIERS IN PLANT SCIENCE 2019; 10:1258. [PMID: 31649713 PMCID: PMC6795766 DOI: 10.3389/fpls.2019.01258] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 09/10/2019] [Indexed: 05/19/2023]
Abstract
Orchids comprise one of the largest, most highly evolved angiosperm families, and form an extremely peculiar group of plants. Various orchids are available through traditional breeding and micro-propagation since they are valuable as potted plants and/or cut flowers in horticultural markets. The flowering of orchids is generally influenced by environmental signals such as temperature and endogenous developmental programs controlled by genetic factors as is usual in many flowering plant species. The process of floral transition is connected to the flower developmental programs that include floral meristem maintenance and floral organ specification. Thanks to advances in molecular and genetic technologies, the understanding of the molecular mechanisms underlying orchid floral transition and flower developmental processes have been widened, especially in several commercially important orchids such as Phalaenopsis, Dendrobium and Oncidium. In this review, we consolidate recent progress in research on the floral transition and flower development of orchids emphasizing representative genes and genetic networks, and also introduce a few successful cases of manipulation of orchid flowering/flower development through the application of molecular breeding or biotechnology tools.
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Affiliation(s)
- Shan-Li Wang
- Biotechnology Center in Southern Taiwan (BCST) of the Agricultural Biotechnology Research Center (ABRC), Academia Sinica, Tainan, Taiwan
| | - Kotapati Kasi Viswanath
- Department of Plant Industry, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Chii-Gong Tong
- Biotechnology Center in Southern Taiwan (BCST) of the Agricultural Biotechnology Research Center (ABRC), Academia Sinica, Tainan, Taiwan
| | - Hye Ryun An
- National Institute of Horticultural and Herbal Science (NIHHS), Rural Development Administration (RDA), Wanju-gun, South Korea
| | - Seonghoe Jang
- World Vegetable Center Korea Office (WKO), Wanju-gun, South Korea
- *Correspondence: Seonghoe Jang, ; Fure-Chyi Chen,
| | - Fure-Chyi Chen
- Department of Plant Industry, National Pingtung University of Science and Technology, Pingtung, Taiwan
- *Correspondence: Seonghoe Jang, ; Fure-Chyi Chen,
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Ratanasut K, Rod-In W, Sujipuli K. In planta Agrobacterium -Mediated Transformation of Rice. RICE SCIENCE 2017; 24:181-186. [PMID: 0 DOI: 10.1016/j.rsci.2016.11.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
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Hsing HX, Lin YJ, Tong CG, Li MJ, Chen YJ, Ko SS. Efficient and heritable transformation of Phalaenopsis orchids. BOTANICAL STUDIES 2016; 57:30. [PMID: 28597440 PMCID: PMC5430590 DOI: 10.1186/s40529-016-0146-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 10/13/2016] [Indexed: 05/07/2023]
Abstract
BACKGROUND Phalaenopsis orchid (Phal. orchid) is visually attractive and it is important economic floriculture species. Phal. orchids have many unique biological features. However, investigation of these features and validation on their biological functions are limited due to the lack of an efficient transformation method. RESULTS We developed a heritable and efficient Agrobacterium- mediated transformation using protocorms derived from tetraploid or diploid Phal. orchids. A T-DNA vector construct containing eGFP driven by ubiquitin promoter was subjected to transformation. An approximate 1.2-5.2 % transformation rate was achieved. Genomic PCR confirmed that hygromycin selection marker, HptII gene and target gene eGFP were integrated into the orchid genome. Southern blotting indicated a low T-DNA insertion number in the orchid genome of the transformants. Western blot confirmed the expression of eGFP protein in the transgenic orchids. Furthermore, the GFP signal was detected in the transgenic orchids under microscopy. After backcrossing the pollinia of the transgenic plants to four different Phal. orchid varieties, the BC1 progenies showed hygromycin resistance and all surviving BC1 seedlings were HptII positive in PCR and expressed GFP protein as shown by western blot. CONCLUSIONS This study demonstrated a stable transformation system was generated for Phal. orchids. This useful transformation protocol enables functional genomics studies and molecular breeding.
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Affiliation(s)
- Hong-Xian Hsing
- Academia Sinica Biotechnology Center in Southern Taiwan, Tainan, 741 Taiwan
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, 115 Taiwan
| | - Yi-Jyun Lin
- Academia Sinica Biotechnology Center in Southern Taiwan, Tainan, 741 Taiwan
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, 115 Taiwan
| | - Chii-Gong Tong
- Academia Sinica Biotechnology Center in Southern Taiwan, Tainan, 741 Taiwan
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, 115 Taiwan
| | - Min-Jeng Li
- Academia Sinica Biotechnology Center in Southern Taiwan, Tainan, 741 Taiwan
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, 115 Taiwan
| | - Yun-Jin Chen
- Academia Sinica Biotechnology Center in Southern Taiwan, Tainan, 741 Taiwan
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, 115 Taiwan
| | - Swee-Suak Ko
- Academia Sinica Biotechnology Center in Southern Taiwan, Tainan, 741 Taiwan
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei, 115 Taiwan
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Koh KW, Lu HC, Chan MT. Virus resistance in orchids. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2014; 228:26-38. [PMID: 25438783 DOI: 10.1016/j.plantsci.2014.04.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2014] [Revised: 04/07/2014] [Accepted: 04/17/2014] [Indexed: 06/04/2023]
Abstract
Orchid plants, Phalaenopsis and Dendrobium in particular, are commercially valuable ornamental plants sold worldwide. Unfortunately, orchid plants are highly susceptible to viral infection by Cymbidium mosaic virus (CymMV) and Odotoglossum ringspot virus (ORSV), posing a major threat and serious economic loss to the orchid industry worldwide. A major challenge is to generate an effective method to overcome plant viral infection. With the development of optimized orchid transformation biotechnological techniques and the establishment of concepts of pathogen-derived resistance (PDR), the generation of plants resistant to viral infection has been achieved. The PDR concept involves introducing genes that is(are) derived from the virus into the host plant to induce RNA- or protein-mediated resistance. We here review the fundamental mechanism of the PDR concept, and illustrate its application in protecting against viral infection of orchid plants.
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Affiliation(s)
- Kah Wee Koh
- Academia Sinica Biotechnology Center in Southern Taiwan, Tainan, Taiwan
| | - Hsiang-Chia Lu
- Academia Sinica Biotechnology Center in Southern Taiwan, Tainan, Taiwan
| | - Ming-Tsair Chan
- Academia Sinica Biotechnology Center in Southern Taiwan, Tainan, Taiwan; Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan.
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Gnasekaran P, James Antony JJ, Uddain J, Subramaniam S. Agrobacterium-mediated transformation of the recalcitrant Vanda Kasem's Delight orchid with higher efficiency. ScientificWorldJournal 2014; 2014:583934. [PMID: 24977213 PMCID: PMC4000978 DOI: 10.1155/2014/583934] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2014] [Accepted: 03/06/2014] [Indexed: 11/18/2022] Open
Abstract
The presented study established Agrobacterium-mediated genetic transformation using protocorm-like bodies (PLBs) for the production of transgenic Vanda Kasem's Delight Tom Boykin (VKD) orchid. Several parameters such as PLB size, immersion period, level of wounding, Agrobacterium density, cocultivation period, and concentration of acetosyringone were tested and quantified using gusA gene expression to optimize the efficiency of Agrobacterium-mediated genetic transformation of VKD's PLBs. Based on the results, 3-4 mm PLBs wounded by scalpel and immersed for 30 minutes in Agrobacterium suspension of 0.8 unit at A 600 nm produced the highest GUS expression. Furthermore, cocultivating infected PLBs for 4 days in the dark on Vacin and Went cocultivation medium containing 200 μM acetosyringone enhanced the GUS expression. PCR analysis of the putative transformants selected in the presence of 250 mg/L cefotaxime and 30 mg/L geneticin proved the presence of wheatwin1, wheatwin2, and nptII genes.
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Affiliation(s)
- Pavallekoodi Gnasekaran
- School of Biological Sciences, Universiti Sains Malaysia (USM), 11800 Minden Heights, Penang, Malaysia
| | | | - Jasim Uddain
- School of Biological Sciences, Universiti Sains Malaysia (USM), 11800 Minden Heights, Penang, Malaysia
| | - Sreeramanan Subramaniam
- School of Biological Sciences, Universiti Sains Malaysia (USM), 11800 Minden Heights, Penang, Malaysia
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Mondragón-Palomino M. Perspectives on MADS-box expression during orchid flower evolution and development. FRONTIERS IN PLANT SCIENCE 2013; 4:377. [PMID: 24065980 PMCID: PMC3779858 DOI: 10.3389/fpls.2013.00377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 09/03/2013] [Indexed: 05/09/2023]
Abstract
The diverse morphology of orchid flowers and their complex, often deceptive strategies to become pollinated have fascinated researchers for a long time. However, it was not until the 20th century that the ontogeny of orchid flowers, the genetic basis of their morphology and the complex phylogeny of Orchidaceae were investigated. In parallel, the improvement of techniques for in vitro seed germination and tissue culture, together with studies on biochemistry, physiology, and cytology supported the progress of what is now a highly productive industry of orchid breeding and propagation. In the present century both basic research in orchid flower evo-devo and the interest for generating novel horticultural varieties have driven the characterization of many members of the MADS-box family encoding key regulators of flower development. This perspective summarizes the picture emerging from these studies and discusses the advantages and limitations of the comparative strategy employed so far. I address the growing role of natural and horticultural mutants in these studies and the emergence of several model species in orchid evo-devo and genomics. In this context, I make a plea for an increasingly integrative approach.
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Affiliation(s)
- Mariana Mondragón-Palomino
- Department of Cell Biology and Plant Biochemistry, Faculty of Biology and Preclinical Medicine, University of Regensburg, Regensburg, Germany
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13
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Hsiao YY, Chen YW, Huang SC, Pan ZJ, Fu CH, Chen WH, Tsai WC, Chen HH. Gene discovery using next-generation pyrosequencing to develop ESTs for Phalaenopsis orchids. BMC Genomics 2011; 12:360. [PMID: 21749684 PMCID: PMC3146457 DOI: 10.1186/1471-2164-12-360] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2011] [Accepted: 07/12/2011] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Orchids are one of the most diversified angiosperms, but few genomic resources are available for these non-model plants. In addition to the ecological significance, Phalaenopsis has been considered as an economically important floriculture industry worldwide. We aimed to use massively parallel 454 pyrosequencing for a global characterization of the Phalaenopsis transcriptome. RESULTS To maximize sequence diversity, we pooled RNA from 10 samples of different tissues, various developmental stages, and biotic- or abiotic-stressed plants. We obtained 206,960 expressed sequence tags (ESTs) with an average read length of 228 bp. These reads were assembled into 8,233 contigs and 34,630 singletons. The unigenes were searched against the NCBI non-redundant (NR) protein database. Based on sequence similarity with known proteins, these analyses identified 22,234 different genes (E-value cutoff, e-7). Assembled sequences were annotated with Gene Ontology, Gene Family and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Among these annotations, over 780 unigenes encoding putative transcription factors were identified. CONCLUSION Pyrosequencing was effective in identifying a large set of unigenes from Phalaenopsis. The informative EST dataset we developed constitutes a much-needed resource for discovery of genes involved in various biological processes in Phalaenopsis and other orchid species. These transcribed sequences will narrow the gap between study of model organisms with many genomic resources and species that are important for ecological and evolutionary studies.
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Affiliation(s)
- Yu-Yun Hsiao
- Department of Life Sciences, National Cheng Kung University, Tainan 701, Taiwan
- Orchid Research Center, National Cheng Kung University, Tainan 701, Taiwan
| | - Yun-Wen Chen
- Institute of Tropical Plant Sciences, National Cheng Kung University, Tainan 701, Taiwan
| | - Shi-Ching Huang
- Department of Life Sciences, National Cheng Kung University, Tainan 701, Taiwan
| | - Zhao-Jun Pan
- Department of Life Sciences, National Cheng Kung University, Tainan 701, Taiwan
| | - Chih-Hsiung Fu
- Department of Engineering Science, National Cheng Kung University, Tainan 701, Taiwan
| | - Wen-Huei Chen
- Orchid Research Center, National Cheng Kung University, Tainan 701, Taiwan
| | - Wen-Chieh Tsai
- Orchid Research Center, National Cheng Kung University, Tainan 701, Taiwan
- Institute of Tropical Plant Sciences, National Cheng Kung University, Tainan 701, Taiwan
| | - Hong-Hwa Chen
- Department of Life Sciences, National Cheng Kung University, Tainan 701, Taiwan
- Orchid Research Center, National Cheng Kung University, Tainan 701, Taiwan
- Institute of Tropical Plant Sciences, National Cheng Kung University, Tainan 701, Taiwan
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Schlüter PM, Schiestl FP. Molecular mechanisms of floral mimicry in orchids. TRENDS IN PLANT SCIENCE 2008; 13:228-235. [PMID: 18424223 DOI: 10.1016/j.tplants.2008.02.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2007] [Revised: 02/04/2008] [Accepted: 02/12/2008] [Indexed: 05/26/2023]
Abstract
Deceptive plants do not produce floral rewards, but attract pollinators by mimicking signals of other organisms, such as food plants or female insects. Such floral mimicry is particularly common in orchids, in which flower morphology, coloration and odour play key roles in deceiving pollinators. A better understanding of the molecular bases for these traits should provide new insights into the occurrence, mechanisms and evolutionary consequences of floral mimicry. It should also reveal the molecular bases of pollinator-attracting signals, in addition to providing strategies for manipulating insect behaviour in general. Here, we review data on the molecular bases for traits involved in floral mimicry, and we describe methodological advances helpful for the functional evaluation of key genes.
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Affiliation(s)
- Philipp M Schlüter
- Institute of Systematic Botany, University of Zurich, Zollikerstrasse 107, Zurich, Switzerland.
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15
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Ogaki M, Furuichi Y, Kuroda K, Chin DP, Ogawa Y, Mii M. Importance of co-cultivation medium pH for successful Agrobacterium-mediated transformation of Lilium x formolongi. PLANT CELL REPORTS 2008; 27:699-705. [PMID: 18060407 DOI: 10.1007/s00299-007-0481-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2007] [Revised: 11/03/2007] [Accepted: 11/13/2007] [Indexed: 05/25/2023]
Abstract
An efficient system for Agrobacterium-mediated transformation of Lilium x formolongi was established by preventing the drastic drop of pH in the co-cultivation medium with MES. Meristematic nodular calli were inoculated with an overnight culture of A. tumefaciens strain EHA101 containing the plasmid pIG121-Hm which harbored intron-containing beta-glucuronidase (GUS), hygromycin phosphotransferase (HPT), and neomycin phosphotransfease II (NPTII) genes. After three days of co-cultivation on 2 g/l gellan gum-solidified MS medium containing 100 microM acetosyringone, 30 g/l sucrose, 1 mg/l picloram and different concentrations of MES, they were cultured on the same medium containing 12.5 mg/l meropenem to eliminate Agrobacterium for 2 weeks and then transferred onto medium containing the same concentration of meropenem and 25 mg/l hygromycin for selecting putative transgenic calli. Transient GUS expression was only observed by adding MES to co-cultivation medium. Hygromycin-resistant transgenic calli were obtained only when MES was added to the co-cultivation medium especially at 10 mM. The hygromycin-resistant calli were successfully regenerated into plantlets after transferring onto picloram-free medium. Transformation of plants was confirmed by histochemical GUS assay, PCR analysis and Southern blot analysis.
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Affiliation(s)
- M Ogaki
- Graduate School of Horticulture, Chiba University,Matsudo, Chiba, 271-8510, Japan.
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16
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. PA, . SB, . PT. Agrobacterium-Mediated Transformation of Dendrobium secundum (Bl.) Lindl with Antisense ACC Oxidase. ACTA ACUST UNITED AC 2007. [DOI: 10.3923/ajps.2007.1065.1071] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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17
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Chai D, Lee SM, Ng JH, Yu H. l-Methionine sulfoximine as a novel selection agent for genetic transformation of orchids. J Biotechnol 2007; 131:466-72. [PMID: 17825935 DOI: 10.1016/j.jbiotec.2007.07.951] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2007] [Revised: 07/09/2007] [Accepted: 07/20/2007] [Indexed: 11/28/2022]
Abstract
A key challenge in molecular breeding of orchids is the creation of efficient and reproducible gene transformation systems. In this study, we report a new transformation method utilizing L-methionine sulfoximine (MSO) as a novel agent for selection of transgenic Dendrobium hybrids D. Madame Thong-In and D. Chao Praya Smile with the bialaphos resistance (bar) gene as a selectable marker. Gene transformation was performed by biolistic bombardment with a 4-day recovery period on MSO-free medium and two selection stages on media with increasing amounts of selection agent, using concentrations of 5 and 10 microM MSO for D. Madame Thong-In, and 0.5 and 2 microM MSO for D. Chao Praya Smile. Independent transgenic orchid lines were obtained and the presence of the transgene was confirmed by PCR and Southern blot analysis. Because of substantial time and economic savings, the new transformation system using MSO as a selection agent will facilitate functional studies on orchid genes and genetic engineering of orchids with commercially valuable traits.
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Affiliation(s)
- Davina Chai
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore
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18
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19
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Chin DP, Mishiba KI, Mii M. Agrobacterium-mediated transformation of protocorm-like bodies in Cymbidium. PLANT CELL REPORTS 2007; 26:735-43. [PMID: 17205333 DOI: 10.1007/s00299-006-0284-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2006] [Revised: 11/27/2006] [Accepted: 12/03/2006] [Indexed: 05/13/2023]
Abstract
Genetically transformed plants of Cymbidium were regenerated after cocultivating protocorm-like bodies (PLB) with Agrobacterium tumefaciens strain EHA101 (pIG121Hm) that harbored genes for beta-glucuronidase (gus), hygromycin phosphotransferase (hpt) and neomycin phosphotransferase II (nptII). PLB of three genotypes maintained in liquid new Dogashima medium (NDM), were subjected to transformation experiments. The PLB inoculated with Agrobacterium produced secondary PLB, 4 weeks after transfer onto 2.5 g L(-1) gellan gum-solidified NDM containing 10 g L(-1) sucrose, 20 mg L(-1) hygromycin and 40 mg L(-1) meropenem. Transformation efficiency was affected by genotype and the presence of acetosyringone during cocultivation. The highest transformation efficiency was obtained when PLB from the genotype L4 were infected and cocultivated with Agrobacterium on medium containing 100 muM acetosyringone. Transformation of the hygromycin-resistant plantlets regenerated from different sites of inoculated PLB was confirmed by histochemical GUS assay, PCR analysis and Southern blot hybridization.
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Affiliation(s)
- Dong Poh Chin
- Laboratory of Plant Cell Technology, Faculty of Horticulture, Chiba University, Chiba, Japan.
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20
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Yip MK, Huang HE, Ger MJ, Chiu SH, Tsai YC, Lin CI, Feng TY. Production of soft rot resistant calla lily by expressing a ferredoxin-like protein gene (pflp) in transgenic plants. PLANT CELL REPORTS 2007; 26:449-57. [PMID: 17033825 DOI: 10.1007/s00299-006-0246-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2006] [Revised: 08/30/2006] [Accepted: 09/04/2006] [Indexed: 05/12/2023]
Abstract
An efficient protocol for the Agrobacterium tumefaciens-mediated transformation of calla lily (Zantedeschia elliottiana (W. Wats.) Engl. cultivar 'Florex Gold') is described. Shoot basal discs were co-cultivated with A. tumefaciens C58C1 carrying a plasmid containing neomycin phosphotransferase (nptII) and plant ferredoxin-like protein (pflp) genes. After Agrobacterium co-cultivation, the shoot basal discs were exposed to 100 mg l(-1) kanamycin for selection. Twenty-eight out of 260 discs (10.8%) were found to have survived and produced shoot clusters. Twenty-six of these were confirmed to contain the pflp transgene by PCR, ending up in 10% transformation efficiency. The disease resistance investigation revealed that 18 transgenic plants exhibited resistance to soft rot disease caused by Erwinia carotovora subsp. carotovora. The presence of pflp gene was demonstrated by PCR, and its accumulation and activity was confirmed by Western blot and disease resistance assay. This was the first report to show the successful transformation and resistance to a bacterial pathogen in Zantedeschia. The protocol is useful for the quality improvement of calla lily through genetic transformation.
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Affiliation(s)
- Mei-Kuen Yip
- Institute of Plant and Microbial Biology, Academic Sinica, Nankang, Taipei, Taiwan, ROC
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21
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Malabadi RB, Nataraja K. Genetic Transformation of Vanilla planifolia by Agrobacterium-tumefaciens Using Shoot Tip Sections. ACTA ACUST UNITED AC 2007. [DOI: 10.3923/rjb.2007.86.94] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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22
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CAO Y, Niimi Y, HU SL. Meropenem as an Alternative Antibiotic Agent for Suppression of Agrobacterium in Genetic Transformation of Orchid. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/s1671-2927(06)60133-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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23
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. SS, . MM, . MA, . MS, . RX. Transient Expression of gusA and gfp Gene in Agrobacterium-mediated Banana Transformation Using Single Tiny Meristematic Bud. ACTA ACUST UNITED AC 2006. [DOI: 10.3923/ajps.2006.468.480] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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24
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Song IJ, Nakamura T, Fukuda T, Yokoyama J, Ito T, Ichikawa H, Horikawa Y, Kameya T, Kanno A. Spatiotemporal expression of duplicate AGAMOUS orthologues during floral development in Phalaenopsis. Dev Genes Evol 2006; 216:301-13. [PMID: 16463041 DOI: 10.1007/s00427-005-0057-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2005] [Accepted: 12/21/2005] [Indexed: 10/25/2022]
Abstract
The AGAMOUS (AG) family of MADS-box genes plays important roles in controlling the development of the reproductive organs of flowering plants. To understand the molecular mechanisms behind the floral development in the orchid, we isolated and characterized two AG-like genes from Phalaenopsis that we denoted PhalAG1 and PhalAG2. Phylogenetic analysis indicated that PhalAG1 and PhalAG2 fall into different phylogenetic positions in the AG gene family as they belong to the C- and D-lineages, respectively. Reverse transcription-polymerase chair reaction (RT-PCR) analyses showed that PhalAG1 and PhalAG2 transcripts were detected in flower buds but not in vegetative organs. Moreover, in situ hybridization experiments revealed that PhalAG1 and PhalAG2 hybridization signals were observed in the lip, column, and ovule during the floral development of Phalaenopsis, with little difference between the expression patterns of the two genes. These results suggest that both AG-like genes in Phalaenopsis act redundantly with each other in floral development.
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Affiliation(s)
- In-Ja Song
- Graduate School of Life Sciences, Tohoku University, Katahira 2-1-1, Sendai 980-8577, Japan
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Chen L, Kawai H, Oku T, Takahashi C, Niimi Y. Introduction of Odontoglossum ringspot virus Coat Protein Gene into Cymbidium niveo-marginatum mediated by Agrobacterium tumefaciens to Produce Transgenic Plants. ACTA ACUST UNITED AC 2006. [DOI: 10.2503/jjshs.75.249] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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26
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Mishiba KI, Chin DP, Mii M. Agrobacterium-mediated transformation of Phalaenopsis by targeting protocorms at an early stage after germination. PLANT CELL REPORTS 2005; 24:297-303. [PMID: 15800779 DOI: 10.1007/s00299-005-0938-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2004] [Revised: 01/25/2005] [Accepted: 01/31/2005] [Indexed: 05/07/2023]
Abstract
A transformation procedure for phalaenopsis orchid established by using immature protocorms for Agrobacterium infection was aimed at the introduction of target genes into individuals with divergent genetic backgrounds. Protocorms obtained after 21 days of culture on liquid New Dogashima medium were inoculated with Agrobacterium strain EHA101(pIG121Hm) harboring both beta-glucuronidase (GUS) and hygromycin resistance genes. Subculture of the protocorms on acetosyringone-containing medium 2 days before Agrobacterium inoculation gave the highest transformation efficiencies (1.3-1.9%) based on the frequency of hygromycin-resistant plants produced. Surviving protocorms obtained 2 months after Agrobacterium infection on selection medium containing 20 mg l(-1) hygromycin were cut transversely into two pieces before transferring to recovery medium without hygromycin. Protocorm-like bodies (PLBs) proliferated from pieces of protocorms during a 1-month culture on recovery medium followed by transfer to selection medium. Hygromycin-resistant phalaenopsis plants that regenerated after the re-selection culture of PLBs showed histochemical blue staining due to GUS. Transgene integration of the hygromycin-resistant plants was confirmed by Southern blot analysis. A total of 88 transgenic plants, each derived from an independent protocorm, was obtained from ca. 12,500 mature seeds 6 months after infection with Agrobacterium. Due to the convenient protocol for Agrobacterium infection and rapid production of transgenic plants, the present procedure could be utilized to assess expression of transgenes under different genetic backgrounds, and for the molecular breeding of phalaenopsis.
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Affiliation(s)
- Kei-ichiro Mishiba
- Laboratory of Plant Cell Technology, Faculty of Horticulture, Chiba University, 648 Matsudo, Matsudo City, Chiba, 271-8510, Japan.
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27
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You SJ, Liau CH, Huang HE, Feng TY, Prasad V, Hsiao HH, Lu JC, Chan MT. Sweet pepper ferredoxin-like protein ( pflp) gene as a novel selection marker for orchid transformation. PLANTA 2003; 217:60-65. [PMID: 12721849 DOI: 10.1007/s00425-002-0970-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2002] [Accepted: 11/30/2002] [Indexed: 05/24/2023]
Abstract
A novel method for selection of transgenic plants utilizing the sweet pepper ( Capsicum annuum L.) ferredoxin-like protein ( pflp) gene as selection marker and Erwinia carotovora as the selection agent has been developed. An expression vector containing a pflp cDNA driven by a cauliflower mosaic virus 35S promoter was successfully transformed into protocorm-like bodies of Oncidium orchid by Agrobacterium tumefaciens and particle bombardment, respectively. Erwinia carotovora was used as a selection agent to screen transformants, thereby obtaining transgenic plants without the use of an antibiotic selection agent. A total of 32 independent transgenic orchid lines were obtained, out of which 9 transgenic lines (beta-glucuronidase positive) were randomly selected and confirmed by Southern and northern blot analyses. The transgenic orchid plants showed enhanced resistance to E. carotovora, even when the entire plant was challenged with the pathogen. Our results suggest the novel use of the pflp gene as a resistance selection marker in plant genetic engineering strategies. In the future, the use of the pflp gene as a selection marker may facilitate the use of smaller gene constructs due to removal of bulky antibiotic selection and reporter genes. These constructs can then be used to incorporate additional genes of choice.
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Affiliation(s)
- Su-Juan You
- Institute of BioAgricultural Sciences, Academia Sinica, 11529, Taipei, Taiwan, Republic of China
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28
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Men S, Ming X, Wang Y, Liu R, Wei C, Li Y. Genetic transformation of two species of orchid by biolistic bombardment. PLANT CELL REPORTS 2003; 21:592-598. [PMID: 12789435 DOI: 10.1007/s00299-002-0559-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2002] [Revised: 10/15/2002] [Accepted: 10/29/2002] [Indexed: 05/24/2023]
Abstract
We report here the transformation of two species of orchid, Dendrobium phalaenopsis and D. nobile,by biolistic bombardment. Calli or protocorm-like bodies (PLBs) were used as target explants. Gold particles (1.0 microm) coated with plasmid DNA (pCAMBIA1301) encoding an intron-containing beta-glucuronidase gene (gus-int) and a hygromycin phosphotransferase (hpt) gene were introduced into the PLBs or calli using the Bio-Rad PDS-1000/He Biolistic Particle Delivery System. Calli and PLBs were then chopped up and pre-cultured in 1/2-strength MS medium supplemented with 0.4 M mannitol for a 1-h osmoticum treatment before bombardment. Immediately after bombardment, the calli and PLBs were transferred to 1/2-strength MS medium without mannitol for recovery. Putatively transformed plantlets were obtained by selection and regeneration on medium supplemented with 30 mg/l hygromycin. The highest efficiency of transformation was obtained when selection was conducted at 2 days post-bombardment. For D. phalaenopsis and D. nobile, respectively, about 12% and 2% of the bombarded calli or PLBs produced independent transgenic plants. Integration and expression of the transgenes were confirmed by Southern hybridization and Northern hybridization. No nontransformed plants were regenerated, indicating a tight selection scheme. However, separate incorporation of the gus gene and the hpt gene was observed, and in one transgenic line the gus gene was integrated into the genome of the transgenic plant, but not expressed.
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Affiliation(s)
- S Men
- Peking-Yale Joint Center for Plant Molecular Genetics and Agrobiotechnology, The National Laboratory of Protein Engineering and Plant Genetic Engineering, Department of Biotechnology, College of Life Sciences, Peking University, 100871 Beijing, China
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