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Zhang J, Yang J, Lv Y, Zhang X, Xia C, Zhao H, Wen C. Genetic diversity analysis and variety identification using SSR and SNP markers in melon. BMC PLANT BIOLOGY 2023; 23:39. [PMID: 36650465 PMCID: PMC9847184 DOI: 10.1186/s12870-023-04056-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 01/10/2023] [Indexed: 06/17/2023]
Abstract
Melon is an important horticultural crop with a pleasant aromatic flavor and abundance of health-promoting substances. Numerous melon varieties have been cultivated worldwide in recent years, but the high number of varieties and the high similarity between them poses a major challenge for variety evaluation, discrimination, as well as innovation in breeding. Recently, simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs), two robust molecular markers, have been utilized as a rapid and reliable method for variety identification. To elucidate the genetic structure and diversity of melon varieties, we screened out 136 perfect SSRs and 164 perfect SNPs from the resequencing data of 149 accessions, including the most representative lines worldwide. This study established the DNA fingerprint of 259 widely-cultivated melon varieties in China using Target-seq technology. All melon varieties were classified into five subgruops, including ssp. agrestis, ssp. melo, muskmelon and two subgroups of foreign individuals. Compared with ssp. melo, the ssp. agrestis varieties might be exposed to a high risk of genetic erosion due to their extremely narrow genetic background. Increasing the gene exchange between ssp. melo and ssp. agrestis is therefore necessary in the breeding procedure. In addition, analysis of the DNA fingerprints of the 259 melon varieties showed a good linear correlation (R2 = 0.9722) between the SSR genotyping and SNP genotyping methods in variety identification. The pedigree analysis based on the DNA fingerprint of 'Jingyu' and 'Jingmi' series melon varieties was consistent with their breeding history. Based on the SNP index analysis, ssp. agrestis had low gene exchange with ssp. melo in chromosome 4, 7, 10, 11and 12, two specific SNP loci were verified to distinguish ssp. agrestis and ssp. melon varieties. Finally, 23 SSRs and 40 SNPs were selected as the core sets of markers for application in variety identification, which could be efficiently applied to variety authentication, variety monitoring, as well as the protection of intellectual property rights in melon.
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Affiliation(s)
- Jian Zhang
- Beijing Vegetable Research Center (BVRC), Beijing Academy of Agricultural and Forestry Sciences, National Engineering Research Center for Vegetables, Beijing, 100097, China
- Beijing Key Laboratory of Vegetable Germplasms Improvement, Beijing, 100097, China
| | - Jingjing Yang
- Beijing Vegetable Research Center (BVRC), Beijing Academy of Agricultural and Forestry Sciences, National Engineering Research Center for Vegetables, Beijing, 100097, China
- Beijing Key Laboratory of Vegetable Germplasms Improvement, Beijing, 100097, China
| | - Yanling Lv
- Institute of Vegetable, Liaoning Academy of Agricultural Sciences, Shenyang, 110161, China
| | - Xiaofei Zhang
- Beijing Vegetable Research Center (BVRC), Beijing Academy of Agricultural and Forestry Sciences, National Engineering Research Center for Vegetables, Beijing, 100097, China
- Beijing Key Laboratory of Vegetable Germplasms Improvement, Beijing, 100097, China
| | - Changxuan Xia
- Beijing Vegetable Research Center (BVRC), Beijing Academy of Agricultural and Forestry Sciences, National Engineering Research Center for Vegetables, Beijing, 100097, China
- Beijing Key Laboratory of Vegetable Germplasms Improvement, Beijing, 100097, China
| | - Hong Zhao
- Beijing Vegetable Research Center (BVRC), Beijing Academy of Agricultural and Forestry Sciences, National Engineering Research Center for Vegetables, Beijing, 100097, China
- Beijing Key Laboratory of Vegetable Germplasms Improvement, Beijing, 100097, China
| | - Changlong Wen
- Beijing Vegetable Research Center (BVRC), Beijing Academy of Agricultural and Forestry Sciences, National Engineering Research Center for Vegetables, Beijing, 100097, China.
- Beijing Key Laboratory of Vegetable Germplasms Improvement, Beijing, 100097, China.
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Biotechnological Advances to Improve Abiotic Stress Tolerance in Crops. Int J Mol Sci 2022; 23:ijms231912053. [PMID: 36233352 PMCID: PMC9570234 DOI: 10.3390/ijms231912053] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 10/02/2022] [Accepted: 10/06/2022] [Indexed: 11/16/2022] Open
Abstract
The major challenges that agriculture is facing in the twenty-first century are increasing droughts, water scarcity, flooding, poorer soils, and extreme temperatures due to climate change. However, most crops are not tolerant to extreme climatic environments. The aim in the near future, in a world with hunger and an increasing population, is to breed and/or engineer crops to tolerate abiotic stress with a higher yield. Some crop varieties display a certain degree of tolerance, which has been exploited by plant breeders to develop varieties that thrive under stress conditions. Moreover, a long list of genes involved in abiotic stress tolerance have been identified and characterized by molecular techniques and overexpressed individually in plant transformation experiments. Nevertheless, stress tolerance phenotypes are polygenetic traits, which current genomic tools are dissecting to exploit their use by accelerating genetic introgression using molecular markers or site-directed mutagenesis such as CRISPR-Cas9. In this review, we describe plant mechanisms to sense and tolerate adverse climate conditions and examine and discuss classic and new molecular tools to select and improve abiotic stress tolerance in major crops.
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He J, He Z, Yang D, Ma Z, Chen H, Zhang Q, Deng F, Ye L, Pu Y, Zhang M, Yang S, Yang S, Yan T. Genetic Variation in Schizothorax kozlovi Nikolsky in the Upper Reaches of the Chinese Yangtze River Based on Genotyping for Simplified Genome Sequencing. Animals (Basel) 2022; 12:ani12172181. [PMID: 36077902 PMCID: PMC9454844 DOI: 10.3390/ani12172181] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 08/16/2022] [Accepted: 08/19/2022] [Indexed: 11/23/2022] Open
Abstract
Simple Summary Schizothorax kozlovi Nikolsky is a unique cold−water fish in the upper reaches of the Yangtze River in China and has high economic value. In our study, genetic diversity and population structure analyses were performed on seven wild populations in the upper reaches of the Yangtze River by GBS. The above results indicate that the populations of S. kozlovi have different degrees of tolerance and selection pressure in response to temperature and altitude. The Wujiang population was genetically differentiated from the Jinsha River and Yalong River populations. The Wujiang intrapopulation has greater genetic diversity and differentiation than the Jinsha River and Yalong River populations, which demonstrates that the Jinsha and Yalong populations require more attention and resources for their protection. The results of this study will increase our understanding of the diversity of S. kozlovi in the upper reaches of the Yangtze River and provide a basis for the conservation and utilization of wild resources. Abstract Schizothorax kozlovi Nikolsky is a unique cold−water fish in the upper reaches of the Yangtze River in China and has high economic value. In our study, genetic diversity and population structure analyses were performed on seven wild populations (originating from the Jinsha River, Yalong River, and Wujiang River) in the upper reaches of the Yangtze River by genotyping by sequencing (GBS). The results indicated that a total of 303,970 single−nucleotide polymorphisms (SNPs) were identified from the seven wild populations. Lower genetic diversity was exhibited among the intrapopulations of the three tributaries, and the Wujiang River population had significant genetic differentiation when compared to the Jinsha River and Yalong River populations. Furthermore, the selected SNPs were enriched in cellular processes, environmental adaptation, signal transduction, and related metabolic processes between the Wujiang population and the other two populations. The above results indicate that the populations of S. kozlovi have different degrees of tolerance and selection pressure in response to temperature and altitude. The Wujiang intrapopulation has greater genetic diversity and differentiation than the Jinsha River and Yalong River populations, which demonstrates that the Jinsha and Yalong populations require more attention and resources for their protection. The results of this study will increase our understanding of the diversity of S. kozlovi in the upper reaches of the Yangtze River and provide a basis for the conservation and utilization of wild resources.
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Genome-Wide Identification, Characterization, and Expression Analysis Related to Low-Temperature Stress of the CmGLP Gene Family in Cucumis melo L. Int J Mol Sci 2022; 23:ijms23158190. [PMID: 35897766 PMCID: PMC9330424 DOI: 10.3390/ijms23158190] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 07/20/2022] [Accepted: 07/22/2022] [Indexed: 01/25/2023] Open
Abstract
Germin-like protein (GLP) participates in plant growth and development and plays an important role in plant stress. In the present study, 22 CmGLPs belonging to five classes were identified in the melon genome. Each member of the CmGLPs family contains a typical Cupin_1 domain. We conducted a genome-wide analysis of the melon GLP gene family characterization. CmGLPs were randomly distributed in the melon chromosomes, with the largest number on chromosome 8, having eight family members. Gene duplication events drive the evolution and expansion of the melon GLP gene family. Based on the phylogenetic tree analysis of GLP proteins in melon, rice, Arabidopsis, and cucumber, it was found that the GLP gene families of different species have diverged in evolution. Based on qRT-PCR results, all members of the CmGLP gene family could be expressed in different tissues of melon. Most CmGLP genes were up-regulated after low-temperature stress. The relative expression of CmGLP2-5 increased by 157.13 times at 48 h after low-temperature treatment. This finding suggests that the CmGLP2-5 might play an important role in low-temperature stress in melon. Furthermore, quantitative dual LUC assays indicated that CmMYB23 and CmWRKY33 can bind the promoter fragment of the CmGLP2-5. These results were helpful in understanding the functional succession and evolution of the melon GLP gene family and further revealed the response of CmGLPs to low-temperature stress in melon.
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Chen M, He X, Huang X, Lu T, Zhang Y, Zhu J, Yu H, Luo C. Cis-element amplified polymorphism (CEAP), a novel promoter- and gene-targeted molecular marker of plants. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2022; 28:1407-1419. [PMID: 36051234 PMCID: PMC9424407 DOI: 10.1007/s12298-022-01212-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 02/08/2022] [Accepted: 07/14/2022] [Indexed: 06/15/2023]
Abstract
UNLABELLED In this study, we selected eight cis-elements: AAAG, ACGTG, CCGA, ACTCAT, GGTCA, TATCC, TGAC and GATAA, which are closely related to plant growth and development, signal transduction and stress response. The CEAP primers were 18 nucleotides long and consisted of a central cis-element nucleotide core flanked by a filler sequence at the 5' end and di- or tri-nucleotides at the 3' end. A total of two hundred and twenty-four primers were developed, and the PCR procedure consisted of 5 cycles of low-temperature annealing and 35 subsequent cycles of annealing at 50°C. The PCR products are electrophoretically separated by 1.8-2.3% agarose. The polymorphism of the CEAP marker was amplified in eight mango (Mangifera indica L.) species. The results showed that the CEAP primers could amplify clear, repeatable bands in mango and combine at least four cis-elements from which a large number of bands were amplified and six highly polymorphic primers for each cis-element can reach an accurate clustering result. The results of CEAP marker assays compared with ISSR, CBDP and iPBS marker assays showed that CEAP marker was better than the other three markers in the number of fragment bands, H and I indexes. In addition, we also tested the CEAP markers in rice, tomato, potato, wax gourd, citrus and longan and the results showed that the CEAP marker assay could amplify clear polymorphic bands in different species. Our results indicate that the CEAP markers could be universally used in different species for genetic diversity analysis, relationship analysis, and marker-assisted selection for breeding. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s12298-022-01212-5.
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Affiliation(s)
- Meiyan Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, 530004 Guangxi People’s Republic of China
| | - Xinhua He
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, 530004 Guangxi People’s Republic of China
| | - Xing Huang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, 530004 Guangxi People’s Republic of China
| | - Tingting Lu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, 530004 Guangxi People’s Republic of China
| | - Yili Zhang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, 530004 Guangxi People’s Republic of China
| | - Jiawei Zhu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, 530004 Guangxi People’s Republic of China
| | - Haixia Yu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, 530004 Guangxi People’s Republic of China
| | - Cong Luo
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, National Demonstration Center for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning, 530004 Guangxi People’s Republic of China
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Flores-León A, Peréz Moro C, Martí R, Beltran J, Roselló S, Cebolla-Cornejo J, Picó B. Spanish Melon Landraces: Revealing Useful Diversity by Genomic, Morphological, and Metabolomic Analysis. Int J Mol Sci 2022; 23:ijms23137162. [PMID: 35806170 PMCID: PMC9266967 DOI: 10.3390/ijms23137162] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 06/26/2022] [Accepted: 06/26/2022] [Indexed: 12/02/2022] Open
Abstract
Spain is a secondary centre of the diversification of the melon (Cucumis melo L.), with high diversity represented in highly appreciated landraces belonging to the Flexuosus and Ibericus groups. A collection of 47 accessions of Flexuosus, Chate, Piel de Sapo, Tendral, Amarillo, Blanco, and Rochet was analysed using a genotyping-by-sequencing (GBS) approach. A total of 66,971 quality SNPs were identified. Genetic analysis differentiated Ibericus accessions and exotic materials (Ameri, Momordica, Kachri, and Agrestis), while Flexuous accessions shared ancestry between them. Within the Ibericus group, no clear genomic distinction could be identified for the different landraces evaluated, with accessions of different landraces showing high genetic similarity. The morphological characterization confirmed that the external colour and fruit shape had been used as recognition patterns for Spanish melon landraces, but variability within a landrace exists. Differences were found in the sugars and acid and volatile profiles of the materials. Flexuosus and Chate melons at the immature commercial stage accumulated malic acid and low levels of hexoses, while Ibericus melons accumulated high contents of sucrose and citric acid. Specific trends could be identified in the Ibericus landraces. Tendral accumulated low levels of sugars and citric acid and high of malic acid, maintaining higher firmness, Rochet reached higher levels of sugars, and Amarillo tended to lower malic acid contents. Interestingly, high variability was found within landraces for the acidic profile, offering possibilities to alter taste tinges. The main volatile organic compounds (VOCs) in Flexuosus and Chate were aldehydes and alcohols, with clear differences between both groups. In the Ibericus landraces, general trends for VOC accumulation could be identified, but, again, a high level of variation exists. This situation highlights the necessity to develop depuration programs to promote on-farm in situ conservation and, at the same time, offers opportunities to establish new breeding program targets and to take advantage of these sources of variation.
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Affiliation(s)
- Alejandro Flores-León
- COMAV, Instituto de Conservación y Mejora de la Agrodiversidad, Universitat Politècnica de València, Cno. de Vera, s.n., 46022 València, Spain; (A.F.-L.); (C.P.M.); (B.P.)
| | - Clara Peréz Moro
- COMAV, Instituto de Conservación y Mejora de la Agrodiversidad, Universitat Politècnica de València, Cno. de Vera, s.n., 46022 València, Spain; (A.F.-L.); (C.P.M.); (B.P.)
| | - Raul Martí
- Joint Research Unit UJI/UPV—Improvement of Agri-Food Quality, Universitat Politècnica de València, Cno. de Vera, s.n., 46022 València, Spain;
| | - Joaquin Beltran
- Instituto Universitario de Plaguicidas y Aguas (IUPA), Campus de Riu Sec, Universitat Jaume I, Avda. Sos Baynat s/n, 12071 Castellón, Spain;
| | - Salvador Roselló
- Joint Research Unit UJI/UPV—Improvement of Agri-Food Quality, Department de Ciències Agràries i del Medi Natural, Universitat Jaume I, Avda. Sos Baynat s/n, 12071 Castellón, Spain;
| | - Jaime Cebolla-Cornejo
- Joint Research Unit UJI/UPV—Improvement of Agri-Food Quality, Universitat Politècnica de València, Cno. de Vera, s.n., 46022 València, Spain;
- Correspondence:
| | - Belen Picó
- COMAV, Instituto de Conservación y Mejora de la Agrodiversidad, Universitat Politècnica de València, Cno. de Vera, s.n., 46022 València, Spain; (A.F.-L.); (C.P.M.); (B.P.)
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Wang Y, Lei Z, Ye R, Zhou W, Zhou Y, Zou Z, Li J, Yi L, Dai Z. Effects of Cadmium on Physiochemistry and Bioactive Substances of Muskmelon ( Cucumis melo L.). Molecules 2022; 27:molecules27092913. [PMID: 35566265 PMCID: PMC9101123 DOI: 10.3390/molecules27092913] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 04/16/2022] [Accepted: 04/28/2022] [Indexed: 02/05/2023] Open
Abstract
Muskmelon pedicel is the fruit stalk of muskmelon and one of the traditional Chinese medicines, which can be used to treat jaundice, diabetes and neuropathy. However, in recent years, agricultural soil heavy metal cadmium (Cd) pollution has become serious, coupled with the imperfect sales management of herbal medicine, increasing the potential health risk of contaminated herbal medicine in the human body. In this paper, the comprehensive quality of contaminated muskmelon was tested. The results showed that Cd stress significantly inhibited the growth of muskmelon plants, reduced the anthocyanin and chlorophyll contents, and increased the fruit size and sweetness of muskmelon. In addition, heavy metal Cd can also cause oxidative stress in plants, resulting in a series of changes in antioxidant enzyme activities. In the experimental group, the content of polyphenols and saponins increased by 27.02% and 23.92%, respectively, after high-concentration Cd treatment, which may be a mechanism of plant resistance to stress. This paper reveals that the content of bioactive substances in Chinese herbal medicine is high, but the harm in heavy metals cannot be underestimated, which should be paid attention to by relevant departments.
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Affiliation(s)
- Yunqiang Wang
- Institute of Economic Crops, Hubei Academy of Agricultural Science, Wuhan 430064, China; (Y.W.); (W.Z.); (L.Y.)
- Vegetable Germplasm Innovation and Genetic Improvement Key Laboratory of Hubei Province, Hubei Academy of Agricultural Science, Wuhan 430064, China
| | - Zhen Lei
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070, China; (Z.L.); (R.Y.); (Y.Z.); (Z.Z.)
| | - Rongbin Ye
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070, China; (Z.L.); (R.Y.); (Y.Z.); (Z.Z.)
| | - Wei Zhou
- Institute of Economic Crops, Hubei Academy of Agricultural Science, Wuhan 430064, China; (Y.W.); (W.Z.); (L.Y.)
- Vegetable Germplasm Innovation and Genetic Improvement Key Laboratory of Hubei Province, Hubei Academy of Agricultural Science, Wuhan 430064, China
| | - Ying Zhou
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070, China; (Z.L.); (R.Y.); (Y.Z.); (Z.Z.)
| | - Zhengkang Zou
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070, China; (Z.L.); (R.Y.); (Y.Z.); (Z.Z.)
| | - Junli Li
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070, China; (Z.L.); (R.Y.); (Y.Z.); (Z.Z.)
- Correspondence: (J.L.); (Z.D.)
| | - Licong Yi
- Institute of Economic Crops, Hubei Academy of Agricultural Science, Wuhan 430064, China; (Y.W.); (W.Z.); (L.Y.)
- Vegetable Germplasm Innovation and Genetic Improvement Key Laboratory of Hubei Province, Hubei Academy of Agricultural Science, Wuhan 430064, China
| | - Zhaoyi Dai
- Institute of Economic Crops, Hubei Academy of Agricultural Science, Wuhan 430064, China; (Y.W.); (W.Z.); (L.Y.)
- Vegetable Germplasm Innovation and Genetic Improvement Key Laboratory of Hubei Province, Hubei Academy of Agricultural Science, Wuhan 430064, China
- Correspondence: (J.L.); (Z.D.)
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Lai R, Ikram M, Li R, Xia Y, Yuan Q, Zhao W, Zhang Z, Siddique KHM, Guo P. Identification of Novel Quantitative Trait Nucleotides and Candidate Genes for Bacterial Wilt Resistance in Tobacco ( Nicotiana tabacum L.) Using Genotyping-by-Sequencing and Multi-Locus Genome-Wide Association Studies. FRONTIERS IN PLANT SCIENCE 2021; 12:744175. [PMID: 34745174 PMCID: PMC8566715 DOI: 10.3389/fpls.2021.744175] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 09/22/2021] [Indexed: 05/17/2023]
Abstract
Tobacco bacterial wilt (TBW) is a devastating soil-borne disease threatening the yield and quality of tobacco. However, its genetic foundations are not fully understood. In this study, we identified 126,602 high-quality single-nucleotide polymorphisms (SNPs) in 94 tobacco accessions using genotyping-by-sequencing (GBS) and a 94.56 KB linkage disequilibrium (LD) decay rate for candidate gene selection. The population structure analysis revealed two subpopulations with 37 and 57 tobacco accessions. Four multi-locus genome-wide association study (ML-GWAS) approaches identified 142 quantitative trait nucleotides (QTNs) in E1-E4 and the best linear unbiased prediction (BLUP), explaining 0.49-22.52% phenotypic variance. Of these, 38 novel stable QTNs were identified across at least two environments/methods, and their alleles showed significant TBW-DI differences. The number of superior alleles associated with TBW resistance for each accession ranged from 4 to 24; eight accessions had more than 18 superior alleles. Based on TBW-resistant alleles, the five best cross combinations were predicted, including MC133 × Ruyuan No. 1 and CO258 × ROX28. We identified 52 candidate genes around 38 QTNs related to TBW resistance based on homologous functional annotation and KEGG enrichment analysis, e.g., CYCD3;2, BSK1, Nitab4.5_0000641g0050, Nitab4.5_0000929g0030. To the best of our knowledge, this is the first comprehensive study to identify QTNs, superior alleles, and their candidate genes for breeding TBW-resistant tobacco varieties. The results provide further insight into the genetic architecture, marker-assisted selection, and functional genomics of TBW resistance, improving future breeding efforts to increase crop productivity.
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Affiliation(s)
- Ruiqiang Lai
- International Crop Research Center for Stress Resistance, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Muhammad Ikram
- International Crop Research Center for Stress Resistance, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Ronghua Li
- International Crop Research Center for Stress Resistance, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Yanshi Xia
- International Crop Research Center for Stress Resistance, School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Qinghua Yuan
- Crop Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Weicai Zhao
- Nanxiong Research Institute of Guangdong Tobacco Co., Ltd., Nanxiong, China
| | - Zhenchen Zhang
- Crop Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Kadambot H. M. Siddique
- The UWA Institute of Agriculture, UWA School of Agriculture and Environment, The University of Western Australia, Perth, WA, Australia
| | - Peiguo Guo
- International Crop Research Center for Stress Resistance, School of Life Sciences, Guangzhou University, Guangzhou, China
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