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Bishnoi R, Solanki R, Singla D, Mittal A, Chhuneja P, Meena OP, Dhatt AS. Comparative mitochondrial genome analysis reveals a candidate ORF for cytoplasmic male sterility in tropical onion. 3 Biotech 2024; 14:6. [PMID: 38074291 PMCID: PMC10700285 DOI: 10.1007/s13205-023-03850-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 11/08/2023] [Indexed: 01/19/2024] Open
Abstract
Cytoplasmic male sterility (CMS) has been widely exploited for hybrid seed production in onions (Allium cepa L.). In contrast to long-day onion cultivars, short-day onion has not yet been investigated for mitochondrial genome structure and DNA rearrangements associated with CMS activity. Here, we report the 3,16,321 bp complete circular mitochondrial genome of tropical onion CMS line (97A). Due to the substantial number of repetitive regions, the assembled mitochondrial genome of maintainer line (97B) remained linear with 15 scaffolds. Additionally, 13 and 20 chloroplast-derived fragments with a size ranging from 143 to 13,984 bp and 153-17,725 bp were identified in the 97A and 97B genomes, respectively. Genome annotation revealed 24 core protein-coding genes along with 24 and 28 tRNA genes in the mitochondrial genomes of 97A and 97B, respectively. Furthermore, comparative genome analysis of the 97A and 97B mitochondrial genomes showed that gene content was almost similar except for the chimeric ORF725 gene which is the extended form of the COX1 gene. Supplementary Information The online version contains supplementary material available at 10.1007/s13205-023-03850-2.
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Affiliation(s)
- Ritika Bishnoi
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, 141004 India
| | - Ravindra Solanki
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, 141004 India
| | - Deepak Singla
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, 141004 India
| | - Amandeep Mittal
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, 141004 India
| | - Parveen Chhuneja
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, 141004 India
| | - Om Prakash Meena
- Department of Vegetable Science, Punjab Agricultural University, Ludhiana, 141004 India
| | - Ajmer Singh Dhatt
- Department of Vegetable Science, Punjab Agricultural University, Ludhiana, 141004 India
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Ranaware AS, Kunchge NS, Lele SS, Ochatt SJ. Protoplast Technology and Somatic Hybridisation in the Family Apiaceae. PLANTS (BASEL, SWITZERLAND) 2023; 12:1060. [PMID: 36903923 PMCID: PMC10005591 DOI: 10.3390/plants12051060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 02/03/2023] [Accepted: 02/23/2023] [Indexed: 06/18/2023]
Abstract
Species of the family Apiaceae occupy a major market share but are hitherto dependent on open pollinated cultivars. This results in a lack of production uniformity and reduced quality that has fostered hybrid seed production. The difficulty in flower emasculation led breeders to use biotechnology approaches including somatic hybridization. We discuss the use of protoplast technology for the development of somatic hybrids, cybrids and in-vitro breeding of commercial traits such as CMS (cytoplasmic male sterility), GMS (genetic male sterility) and EGMS (environment-sensitive genic male sterility). The molecular mechanism(s) underlying CMS and its candidate genes are also discussed. Cybridization strategies based on enucleation (Gamma rays, X-rays and UV rays) and metabolically arresting protoplasts with chemicals such as iodoacetamide or iodoacetate are reviewed. Differential fluorescence staining of fused protoplast as routinely used can be replaced by new tagging approaches using non-toxic proteins. Here, we focused on the initial plant materials and tissue sources for protoplast isolation, the various digestion enzyme mixtures tested, and on the understanding of cell wall re-generation, all of which intervene in somatic hybrids regeneration. Although there are no alternatives to somatic hybridization, various approaches also discussed are emerging, viz., robotic platforms, artificial intelligence, in recent breeding programs for trait identification and selection.
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Affiliation(s)
- Ankush S. Ranaware
- Institute of Chemical Technology, Marathwada Campus, Jalna 431203, Maharashtra, India
| | - Nandkumar S. Kunchge
- Research and Development Division, Kalash Seeds Pvt. Ltd., Jalna 431203, Maharashtra, India
| | - Smita S. Lele
- Institute of Chemical Technology, Marathwada Campus, Jalna 431203, Maharashtra, India
| | - Sergio J. Ochatt
- Agroécologie, InstitutAgro Dijon, INRAE, Université Bourgogne Franche-Comté, 21000 Dijon, France
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Nie H, Cheng C, Kong J, Li H, Hua J. Plant non-coding RNAs function in pollen development and male sterility. FRONTIERS IN PLANT SCIENCE 2023; 14:1109941. [PMID: 36875603 PMCID: PMC9975556 DOI: 10.3389/fpls.2023.1109941] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 01/23/2023] [Indexed: 06/18/2023]
Abstract
Male sterility is classified as either cytoplasmic male sterility (CMS) or genic male sterility (GMS). Generally, CMS involves mitochondrial genomes interacting with the nuclear genome, while GMS is caused by nuclear genes alone. Male sterility is regulated by multilevel mechanisms in which non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and phased small interfering RNAs (phasiRNAs), which have been proven to be critical elements. The development of high-throughput sequencing technology offers new opportunities to evaluate the genetic mechanism of ncRNAs in plant male sterility. In this review, we summarize the critical ncRNAs that regulate gene expression in ways dependent on or independent of hormones, which involve the differentiation of the stamen primordia, degradation of the tapetum, formation of microspores, and the release of pollen. In addition, the key mechanisms of the miRNA-lncRNA-mRNA interaction networks mediating male sterility in plants are elaborated. We present a different perspective on exploring the ncRNA-mediated regulatory pathways that control CMS in plants and create male-sterile lines through hormones or genome editing. A refined understanding of the ncRNA regulatory mechanisms in plant male sterility for the development of new sterile lines would be conducive to improve hybridization breeding.
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Affiliation(s)
- Hushuai Nie
- Agricultural College, Inner Mongolia Agricultural University, Hohhot, China
- Laboratory of Cotton Genetics, Genomics and Breeding/Key Laboratory of Crop Heterosis and Utilization of Ministry of Education/Beijing Key Laboratory of Crop Genetic Improvement, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Cheng Cheng
- Laboratory of Cotton Genetics, Genomics and Breeding/Key Laboratory of Crop Heterosis and Utilization of Ministry of Education/Beijing Key Laboratory of Crop Genetic Improvement, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Jie Kong
- Institute of Economic Crops, Xinjiang Academy of Agricultural Sciences, Urumqi, Xinjiang, China
| | - Huijing Li
- Laboratory of Cotton Genetics, Genomics and Breeding/Key Laboratory of Crop Heterosis and Utilization of Ministry of Education/Beijing Key Laboratory of Crop Genetic Improvement, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Jinping Hua
- Laboratory of Cotton Genetics, Genomics and Breeding/Key Laboratory of Crop Heterosis and Utilization of Ministry of Education/Beijing Key Laboratory of Crop Genetic Improvement, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
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Xu F, Yang X, Zhao N, Hu Z, Mackenzie SA, Zhang M, Yang J. Exploiting sterility and fertility variation in cytoplasmic male sterile vegetable crops. HORTICULTURE RESEARCH 2022; 9:uhab039. [PMID: 35039865 PMCID: PMC8807945 DOI: 10.1093/hr/uhab039] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 01/18/2022] [Accepted: 10/15/2021] [Indexed: 05/04/2023]
Abstract
Cytoplasmic male sterility (CMS) has long been used to economically produce hybrids that harness growth vigor through heterosis. Yet, how CMS systems operate within commercially viable seed production strategies in various economically important vegetable crops, and their underlying molecular mechanisms, are often overlooked details that could expand the utility of CMS as a cost-effective and stable system. We provide here an update on the nature of cytoplasmic-nuclear interplay for pollen sterility and fertility transitions in vegetable crops, based on the discovery of components of nuclear fertility restoration and reversion determinants. Within plant CMS systems, pollen fertility can be rescued by the introduction of nuclear fertility restorer genes (Rfs), which operate by varied mechanisms to countermand the sterility phenotype. By understanding these systems, it is now becoming feasible to achieve fertility restoration with Rfs designed for programmable CMS-associated open reading frames (ORFs). Likewise, new opportunities exist for targeted disruption of CMS-associated ORFs by mito-TALENs in crops where natural Rfs have not been readily identified, providing an alternative approach to recovering fertility of cytoplasmic male sterile lines in crops. Recent findings show that facultative gynodioecy, as a reproductive strategy, can coordinate the sterility and fertility transition in response to environmental cues and/or metabolic signals that reflect ecological conditions of reproductive isolation. This information is important to devising future systems that are more inherently stable.
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Affiliation(s)
- Fengyuan Xu
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou, Zhejiang, 310058, China
| | - Xiaodong Yang
- Departments of Biology and Plant Science, The Pennsylvania State University, University Park, PA, 16802, USA
- School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, China
| | - Na Zhao
- College of Grassland Science, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China
| | - Zhongyuan Hu
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou, Zhejiang, 310058, China
| | - Sally A Mackenzie
- Departments of Biology and Plant Science, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Mingfang Zhang
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou, Zhejiang, 310058, China
- Hainan Institute, Zhejiang University, Yazhou Bay Science and Technology City, Sanya, 572025, China
- Key Laboratory of Horticultural Plant Growth and Development, Ministry of Agriculture and Rural Affairs, Hangzhou,
Zhejiang, 310058, China
| | - Jinghua Yang
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou, Zhejiang, 310058, China
- Hainan Institute, Zhejiang University, Yazhou Bay Science and Technology City, Sanya, 572025, China
- Key Laboratory of Horticultural Plant Growth and Development, Ministry of Agriculture and Rural Affairs, Hangzhou,
Zhejiang, 310058, China
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Cheng Q, Wang P, Li T, Liu J, Zhang Y, Wang Y, Sun L, Shen H. Complete Mitochondrial Genome Sequence and Identification of a Candidate Gene Responsible for Cytoplasmic Male Sterility in Celery ( Apium graveolens L.). Int J Mol Sci 2021; 22:ijms22168584. [PMID: 34445290 PMCID: PMC8395238 DOI: 10.3390/ijms22168584] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/17/2021] [Accepted: 07/22/2021] [Indexed: 11/17/2022] Open
Abstract
Celery (Apium graveolens L.) is an important leafy vegetable worldwide. The development of F1 hybrids in celery is highly dependent on cytoplasmic male sterility (CMS) because emasculation is difficult. In this study, we first report a celery CMS, which was found in a high-generation inbred line population of the Chinese celery “tanzhixiangqin”. Comparative analysis, following sequencing and assembly of the complete mitochondrial genome sequences for this celery CMS line and its maintainer line, revealed that there are 21 unique regions in the celery CMS line and these unique regions contain 15 ORFs. Among these ORFs, only orf768a is a chimeric gene, consisting of 1497 bp sequences of the cox1 gene and 810 bp unidentified sequences located in the unique region, and the predicted protein product of orf768a possesses 11 transmembrane domains. In summary, the results of this study indicate that orf768a is likely to be a strong candidate gene for CMS induction in celery. In addition, orf768a can be a co-segregate marker, which can be used to screen CMS in celery.
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Affiliation(s)
- Qing Cheng
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, Department of Vegetable Science, College of Horticulture, China Agricultural University, Beijing 100193, China; (Q.C.); (T.L.); (J.L.); (Y.Z.); (Y.W.); (L.S.)
| | - Peng Wang
- Institute of Vegetable Research, Guangxi Academy of Agricultural Sciences, Nanning 530007, China;
| | - Tiantian Li
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, Department of Vegetable Science, College of Horticulture, China Agricultural University, Beijing 100193, China; (Q.C.); (T.L.); (J.L.); (Y.Z.); (Y.W.); (L.S.)
| | - Jinkui Liu
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, Department of Vegetable Science, College of Horticulture, China Agricultural University, Beijing 100193, China; (Q.C.); (T.L.); (J.L.); (Y.Z.); (Y.W.); (L.S.)
| | - Yingxue Zhang
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, Department of Vegetable Science, College of Horticulture, China Agricultural University, Beijing 100193, China; (Q.C.); (T.L.); (J.L.); (Y.Z.); (Y.W.); (L.S.)
| | - Yihao Wang
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, Department of Vegetable Science, College of Horticulture, China Agricultural University, Beijing 100193, China; (Q.C.); (T.L.); (J.L.); (Y.Z.); (Y.W.); (L.S.)
| | - Liang Sun
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, Department of Vegetable Science, College of Horticulture, China Agricultural University, Beijing 100193, China; (Q.C.); (T.L.); (J.L.); (Y.Z.); (Y.W.); (L.S.)
| | - Huolin Shen
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, Department of Vegetable Science, College of Horticulture, China Agricultural University, Beijing 100193, China; (Q.C.); (T.L.); (J.L.); (Y.Z.); (Y.W.); (L.S.)
- Correspondence:
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Khandagale K, Krishna R, Roylawar P, Ade AB, Benke A, Shinde B, Singh M, Gawande SJ, Rai A. Omics approaches in Allium research: Progress and way ahead. PeerJ 2020; 8:e9824. [PMID: 32974094 PMCID: PMC7486827 DOI: 10.7717/peerj.9824] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 08/05/2020] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND The genus Allium (Family: Amaryllidaceae) is an economically important group of crops cultivated worldwide for their use as a vegetable and spices. Alliums are also well known for their nutraceutical properties. Among alliums, onion, garlic, leek, and chives cultivated worldwide. Despite their substantial economic and medicinal importance, the genome sequence of any of the Allium is not available, probably due to their large genome sizes. Recently evolved omics technologies are highly efficient and robust in elucidating molecular mechanisms of several complex life processes in plants. Omics technologies, such as genomics, transcriptomics, proteomics, metabolomics, metagenomics, etc. have the potential to open new avenues in research and improvement of allium crops where genome sequence information is limited. A significant amount of data has been generated using these technologies for various Allium species; it will help in understanding the key traits in Allium crops such as flowering, bulb development, flavonoid biosynthesis, male sterility and stress tolerance at molecular and metabolite level. This information will ultimately assist us in speeding up the breeding in Allium crops. METHOD In the present review, major omics approaches, and their progress, as well as potential applications in Allium crops, could be discussed in detail. RESULTS Here, we have discussed the recent progress made in Allium research using omics technologies such as genomics, transcriptomics, micro RNAs, proteomics, metabolomics, and metagenomics. These omics interventions have been used in alliums for marker discovery, the study of the biotic and abiotic stress response, male sterility, organ development, flavonoid and bulb color, micro RNA discovery, and microbiome associated with Allium crops. Further, we also emphasized the integrated use of these omics platforms for a better understanding of the complex molecular mechanisms to speed up the breeding programs for better cultivars. CONCLUSION All the information and literature provided in the present review throws light on the progress and potential of omics platforms in the research of Allium crops. We also mentioned a few research areas in Allium crops that need to be explored using omics technologies to get more insight. Overall, alliums are an under-studied group of plants, and thus, there is tremendous scope and need for research in Allium species.
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Affiliation(s)
- Kiran Khandagale
- Department of Botany, Savitribai Phule Pune University, Pune, Maharashtra, India
| | - Ram Krishna
- ICAR-Directorate of Onion and Garlic Research, Rajgurunagar, India
| | - Praveen Roylawar
- Department of Botany, S. N. Arts, D. J. M. Commerce and B. N. S. Science College, Sangamner, India
| | - Avinash B. Ade
- Department of Botany, Savitribai Phule Pune University, Pune, Maharashtra, India
| | - Ashwini Benke
- ICAR-Directorate of Onion and Garlic Research, Rajgurunagar, India
| | - Bharat Shinde
- Vidya Pratishthans’s Arts Science and commerce college, Baramati, India
| | - Major Singh
- ICAR-Directorate of Onion and Garlic Research, Rajgurunagar, India
| | | | - Ashutosh Rai
- Crop Improvement, ICAR-Indian Institute of Vegetable Research, Varanasi, India
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Palumbo F, Vitulo N, Vannozzi A, Magon G, Barcaccia G. The Mitochondrial Genome Assembly of Fennel ( Foeniculum vulgare) Reveals Two Different atp6 Gene Sequences in Cytoplasmic Male Sterile Accessions. Int J Mol Sci 2020; 21:E4664. [PMID: 32630002 PMCID: PMC7370444 DOI: 10.3390/ijms21134664] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 06/29/2020] [Accepted: 06/29/2020] [Indexed: 01/12/2023] Open
Abstract
Cytoplasmic male sterility (CMS) has always aroused interest among researchers and breeders, being a valuable resource widely exploited not only to breed F1 hybrid varieties but also to investigate genes that control stamen and pollen development. With the aim of identifying candidate genes for CMS in fennel, we adopted an effective strategy relying on the comparison between mitochondrial genomes (mtDNA) of both fertile and sterile genotypes. mtDNA raw reads derived from a CMS genotype were assembled in a single molecule (296,483 bp), while a draft mtDNA assembly (166,124 nucleotides, 94 contigs) was performed using male fertile sample (MF) sequences. From their annotation and alignment, two atp6-like sequences were identified. atp6-, the putative mutant copy with a 300 bp truncation at the 5'-end, was found only in the mtDNA of CMS samples, while the wild type copy (atp6+) was detected only in the MF mtDNA. Further analyses (i.e., reads mapping and Sanger sequencing), revealed an atp6+ copy also in CMS samples, probably in the nuclear DNA. However, qPCRs performed on different tissues proved that, despite its availability, atp6+ is expressed only in MF samples, while apt6- mRNA was always detected in CMS individuals. In the light of these findings, the energy deficiency model could explain the pollen deficiency observed in male sterile flower. atp6- could represent a gene whose mRNA is translated into a not-fully functional protein leading to suboptimal ATP production that guarantees essential cellular processes but not a high energy demand process such as pollen development. Our study provides novel insights into the fennel mtDNA genome and its atp6 genes, and paves the way for further studies aimed at understanding their functional roles in the determination of male sterility.
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Affiliation(s)
- Fabio Palumbo
- Department of Agronomy Food Natural Resources Animals and Environment (DAFNAE), University of Padova, Campus of Agripolis, Viale dell’Università 16, 35020 Legnaro, PD, Italy; (A.V.); (G.M.); (G.B.)
| | - Nicola Vitulo
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy;
| | - Alessandro Vannozzi
- Department of Agronomy Food Natural Resources Animals and Environment (DAFNAE), University of Padova, Campus of Agripolis, Viale dell’Università 16, 35020 Legnaro, PD, Italy; (A.V.); (G.M.); (G.B.)
| | - Gabriele Magon
- Department of Agronomy Food Natural Resources Animals and Environment (DAFNAE), University of Padova, Campus of Agripolis, Viale dell’Università 16, 35020 Legnaro, PD, Italy; (A.V.); (G.M.); (G.B.)
| | - Gianni Barcaccia
- Department of Agronomy Food Natural Resources Animals and Environment (DAFNAE), University of Padova, Campus of Agripolis, Viale dell’Università 16, 35020 Legnaro, PD, Italy; (A.V.); (G.M.); (G.B.)
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Jo C, Kim S. Transposition of a non-autonomous DNA transposon in the gene coding for a bHLH transcription factor results in a white bulb color of onions (Allium cepa L.). TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2020; 133:317-328. [PMID: 31637460 DOI: 10.1007/s00122-019-03460-8] [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: 03/19/2019] [Accepted: 10/15/2019] [Indexed: 06/10/2023]
Abstract
A DNA transposon was found in the gene encoding a bHLH transcription factor. Genotypes of the marker tagging this DNA transposon perfectly co-segregated with color phenotypes in large F2:3 populations A combined approach of bulked segregant analysis and RNA-Seq was used to isolate causal gene for C locus controlling white bulb color in onions (Allium cepa L.). A total of 114 contigs containing homozygous single nucleotide polymorphisms (SNPs) between white and yellow bulked RNAs were identified. Four of them showed high homologies with loci clustered in the middle of chromosome 5. SNPs in 34 contigs were confirmed by sequencing of PCR products. One of these contigs showed perfect linkage to the C locus in F2:3 populations consisting of 2491 individuals. However, genotypes of molecular marker tagging this contig were inconsistent with color phenotypes of diverse breeding lines. A total of 146 contigs showed differential expression between yellow and white bulks. Among them, transcription levels of B2 gene encoding a bHLH transcription factor were significantly reduced in white RNA bulk and F2:3 individuals, although there was no SNP in the coding region. Phylogenetic analysis showed that onion B2 was orthologous to bHLH-coding genes regulating anthocyanin biosynthesis pathway in other plant species. Promoter regions of B2 gene were obtained by genome walking and a 577-bp non-autonomous DNA transposon designated as AcWHITE was found in the white allele. Molecular marker tagging AcWHITE showed perfect linkage with the C locus. Marker genotypes of the white allele were detected in some white accessions. However, none of tested red or yellow onions contained AcWHITE insertion, implying that B2 gene was likely to be a casual gene for the C locus.
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Affiliation(s)
- Changyeong Jo
- Department of Horticulture, Biotechnology Research Institute, Chonnam National University, Gwangju, 500-757, Korea
| | - Sunggil Kim
- Department of Horticulture, Biotechnology Research Institute, Chonnam National University, Gwangju, 500-757, Korea.
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